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SC-ASHVE-017 St. Louis Public Library American Society of Heating and Ventilating Engineers Heating ventilating air conditioning guide. VOL 18 19 St 628.8 AMERICAN 21718 77300 No- X781017 This Book Shall Not Be Taken From The Library. Heating Ventilating Air Conditioning Guide 1940 rSg^TPT vs . . Heating Ventilating ' Air Conditioning GUIDE 1940 An Instrument of Service prepared for the Profession--Containing a Technical Data Section (ft REFERENCE material on the design and specification of heating, ventilating and air conditioning systems based on--the Transactions--the Investigations of the Research Laboratory and Co operating Institutions--and the Practice of the Members and Friends of the Society . together with a Manufacturers' Catalog Data Section Containing Essential and. Reliable Information Concerning Modern Equipment ' also . The Roll, of Membership of the Society . : -. ; WITH :. *` _. . Complete. Incjexes to Technical and Catalog Data Sections Vol. 18 *781017 Published Annually by American Society of Heating and Ventilating Engineers 51 Madison Avenue New York, N. Y. Copyright 1940 . BY THE American Society of Heating and Ventilating Engineers AND BY IT Dedicated To the Advancement of The Profession and Its Allied Industries text and illustrations are fully pro tected BY COPYRIGHT AND NOTHING THAT APPEARS MAY BE REPRINTED EITHER WHOLLY OR-IN .PART WlfHOylT SPECIAL- PERMJSTJON'. ' ; Printed and Bound by The Horn-Shafer Company BALTIMORE MARYLAND (-t, , f > ,/T r PREFACE TO THE 18th EDITION IN presenting this eighteenth edition of the Heating, Ventilating, Air Conditioning Guide for 1940, the American Society of Heating and Ventilating Engineers recognizes the broad distribution and use which prior editions have attained and, in answer to a popular request, has made a serious attempt to reduce the size and weight of the volume without curtailing the amount of information contained therein. Since the first edition in 1922 there has been a great growth in both the Technical and Catalog Sections, due to a persisting desire of the Society to publish a book of ever-expanding value to the field which it covers. Almost every year there have appeared new chapters on new subjects, and additional tabular, graphical, and textual data on old subjects due largely to the rapid development and progress of the industry. To reverse the trend toward constantly increasing bulk it has been necessary not only to reduce the amount of repetitious material, but also to make use of somewhat thinner paper, after a careful study in which the advantages of lesser weight were balanced against possible dis advantages. For the same reason a number of the Problems in Practice, which have appeared at the end of each chapter for several years, have been omitted, but factual material not already included in the text has been transferred. The sole change in the chapter numbering comes from the division of . last year's Chapter 22 into a new No. 22 covering Unit Heaters, Unit Ventilators and Unit Humidifiers and a new No. 23 for Unit Air Condi tioners, Cooling Units and Attic Fans. Other chapters which have been rewritten or at least restudied particularly for this year complete the list as follows: Physical and Physiological Principles, Heat Transmission Coefficients and Tables, Heating Load, Heating Boilers, Steam Heating Systems, Piping for Steam Heating Systems, Hot Water Heating Systems and Piping, Central Systems for Comfort Air Conditioning, Cooling and Dehumidification Methods, Heat Transfer Surface Coils, Spray Equip ment, Air Cleaning Devices, Air Distribution, Air Duct Design, Air Conditioning in the Treatment of Disease, Pipe and Duct Insulation, Electrical Heating, Radiant Heating, Test Methods and Instruments, and Terminology. The chapter dealing with Heat Transmission Coefficients and Tables has been checked to eliminate obsolete products and to include newly developed ones, where authoritative data' are available. In Chapter 46 the conversion equations have been recomputed from bases selected from the International Critical Tables. In the envelope attached to the inside back cover will be found a Revised Bulkeley Psychrometric Chart with instructions printed thereon. The revised chart has been replotted making it consistent with the Table of Properties of Saturated Water Vapor with Air in Chapter 1. The new chart will be found easier to read and can be used with greater simplicity v in solving psychrometric calculations. The Technical Advisory Com mittee on Psychrometry, functioning under the Committee on Research of; the Society, which has furnished this chart, is now studying funda mental data and will later supply the figures upon which future Guide psychrometric tables and charts will be based. Thus the current chart may be considered an interim one; the partial purpose of which is to develop experience that will help in determining the final form. Other Technical Advisory Committees'of the Committee on Research have also contributed much information and advice that have been exceedingly valuable, and many members of the Society, acting indi vidually or as committeemen, upon request or upon their own initiative, have given freely of their time and knowledge, in order that this book might best serve its purpose. Although the present text is largely carried over from past years, and credit for its composition is due to a large number of Society members, the following accepted and accom plished definite editorial work for this edition: H. E. Adams H. H. Angus F. R. Bichowsky R. C. Cross F. H. Faust M. B. Ferderber R. E. Hattis R. H. Heilman L. N. Hunter H. F. Hutzel L. P. Hynes A. L. Jaros, Jr. J. W. May Joseph Meyer B. F. McLouth D. W. Nelson G. W. Penney T. F. Rockwell E. A. Russell J. B. Schmieler Clifford Strock J. W. Turner G. L. Tuve G. D. WlNANS H. A. Wagner C.-E. A. Winslow In addition to the extensive revisions to the Technical Section the Catalog Data Section has been rearranged to present manufacturers data in logical sequence under five general classifications: air conditioning, air, system equipment, controls and instruments, heating systems and , insulation. Each section has an introductory outline which will also be of assistance to the reader in locating pertinent data in the Technical Section. By thus creating a better coordination between the Technical and Catalog Sections it is expected that the reader can more quickly locate the correct type of equipment for a particular design and also assist the manufacturer in presenting more detailed and more suitable data for the specific application. The Guide Publication is appreciative of the cooperation given by the manufacturers in furnishing useful catalog data and also acknowledges with heartfelt gratitude the help of all those who assisted in whatever way, and extends thanks to them in behalf of the readers. GUIDE PUBLICATION COMMITTEE F. C. McIntosh, Chairman . P. D. Close A. J. Offner C. M. Humphreys S. S. Sanford John James, Technical Secretary VI CONTENTS HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Page Title Page........................................... ;................ ....................................................... iii Preface...................................... _....................................................................... .......... v Code of Ethics for Engineers..... ............. :............................. ...... ...... ................. viii Index to Technical Data.......... ........................................ ....... __....:............... ........ ix Chapter 1. Air, Water and Steam........................ ................._...........................:.... 1 Chapter 2. Refrigerants and Air Drying Agents........................................ ............ 31 Chapter 3. Physical and Physiological Principles........ ...... .......... ........ ................ 45 Chapter 4. Air Pollution.......................... _............................................................... 77 Chapter 5. Heat Transmission Coefficients and Tables.......................................... 85 Chapter 6. Air Leakage............................................................. ............................... 117 Chapter 7. Heating Load...,.................................. ..................... ........ ....... ............;. 127 Chapter 8. Cooling Load............................................................. ...... .1,......^.......... 141 Chapter 9. Combustion and Fuels........ .... ..... ................. ...................... .............1. 157 Chapter 10. Chimneys and Draft Calculationa...... ....................................... ;... 179 Chapter 11. Automatic Fuel'Burning Equipment.... ...........:.................................... 199 Chapter 12. Heat and Fuel Utilization.... ................. ........... ..... .................... ..... ... 223 Chapter 13. Heating Boilers..... .................... 239 Chapter 14. Radiators and Gravity Convectors...................................................... 257 Chapter 15. Steam Heating Systems.................... 267 Chapter 16. Piping for Steam Heating Systems...... ..... 287 Chapter 17. Hot Water Heating Systems and Piping............... _......... .... .......... . 311 Chapter 18. Pipe, Fittings, Welding..,............................ ........................... . . 327 Chapter 19. Gravity Warm Air Furnace Systems.................. ......................... :...... 349 Chapter 20. Mechanical Warm Air Furnace Systems......... ................ 363 Chapter 21. Central Systems for Comfort Air Conditioning.................................. 377 Chapter 22. Unit Heaters, Unit Ventilators, Unit Humidifiers........ .......... 393 Chapter 23. Unit Air Conditioners, Cooling Units, Attic Fans.,............................ 411 Chapter 24. Cooling and Dehumidification Methods ;....... .............. .............. 429 Chapter 25. Heat Transfer Surface^oils............ ................,................................... 459 Chapter 26. Spray Equipment.................................................................................. 487 Chapter 27. Air Cleaning Devices................. ...... :....... ;......... .................................. 505 Chapter 28. Fans...................... ................:..... .......................................................... 515 Chapter 29. Air Distribution... ..............,..................... ...............;............................. 529 Chapter 30. Air Duct Design................. ................ .................................................. 543 Chapter 31. Sound Control ................ ......................... ..............................;...... 561 Chapter 32. Air Conditioning in the Treatment of Disease..................................... 573 Chapter 33. Railway Air Conditioning.............................. ..................................... 585 Chapter 34. Industrial Air Conditioning............................................. ,.................... 595 Chapter 35. Industrial Exhaust Systems..-,................................. ...:......... ............. 605 Chapter 36. Drying Systems................................ .................................................... 619 Chapter 37. Natural Ventilation................................................................................ 639 Chapter 38. Automatic Control................................................................................. 649 Chapter 39. Motors and Controls........... ........................................................ .......... 669 Chapter 40. Pipe and Duct Insulation......................................... ....................... . 683 Chapter 41. Electrical Heating................................................... ..............,............... 705 Chapter 42. Radiant Heating.................,.................................................................. 715 Chapter 43. District Heating...................... 725 Chapter 44. Water Supply Piping andWater Heating........... ................................... 741 Chapter 45. Test Methods and Instruments............... 763 Chapter 46. Terminology............................................................................................ 775 Catalog Data Section........ ...................................... 793 Index to Advertisers.................................................:.......................................... ..... 795 Index to Modern Equipment................................i............................... ....................1065 Roll of Membership....................................................... 1-96 vii H CODE of ETHICS for ENGINEERS NGINEERING work has become an increasingly important factor E in the progress of civilization and in the welfare of the community. The engineering profession is held responsible for the planning, construc tion and operation of such work and is entitled to the position and authority which will enable it to discharge this responsibility and to render effective service to humanity. That the dignity of their chosen profession may be maintained, it is the duty of all engineers to conduct themselves according to the principles of the following Code of Ethics: 1--The engineer will carry on His professional work in a spirit of fairness to employees and contractors, fidelity to clients and employers, loyalty to his country and devotion .to high ideals of ccurtesy and personal honor. 2--He will refrain from associating himself-with or allowing the use of his name by an enterprise of questionable character. 3--He will advertise only in a dignified manner, being careful to avoid misleading statements. 4--He will regard as confidential any information obtained by him as to the business affairs and technical methods or processes of a client or employer. 5--He will inform a client or employer of any business connections, in terests or affiliations which might influence his judgment or impair the disinterested quality of his services. 6--He will refrain from using any improper or questionable methods of soliciting professional work and will decline to pay or to accept com missions for securing such work. 7--He will accept compensation, financial or otherwise, for. a particular service, from one source only, except with the full knowledge and consent of all interested parties. 8--He will not use unfair means to win professional advancement dr to injure the chances of another engineer to secure and hold employment. 9--He will cooperate in upbuilding the engineering profession by exchang ing general information and.experience with his fellow engineers and students of engineering and also by contributing to work of engineering societies, schools of applied science arid the technical press. 10--He will interest himself in the public welfare in behalf of which he will be.ready to apply his special knowledge, skill and training for the use and benefit of mankind. viii 1 INDEX Heating Ventilating Air Conditioning GUIDE 1940 TECHNICAL DATA SECTION CHAPTERS 1-46 and PAGES 1-792 Cross Reference to Subjects in Chapters 1-46 Alphabetically Listed 18th EDITION INDEX HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Technical Data Section Chapters 1 -46 and Pages 1 -792 A Abbreviations, 782 Absolute humidity, 8, 775 Absolute pressure. 766, 775 Absolute temperature, 717 Absolute zero, 775 Absorbents. 40 calcium chloride, 41 lithium chloride, 41 temperature pressure concentrations, 43 Absorption systems, 452 closed, 453 open, 452 lithium chloride, 452 Acceleration, 775 due to gravity, 775 Acclimatization, 58 Activated alumina, 37 - systems, 451 Adiabatic, 775 drier, 621 .. saturation, 2, 22 Adjustable speed motors, 670 . Adsorbents, 37 activated alumina, 37 aluminum oxide, 37 charcoal, 38 lamisilate, 38 . silica gel, 38 silicon dioxide, 38 - , temperature pressure concentrations, 39 Adsorption systems, 450 activated alumina, 451 silica gel, 451 Agitated drier, 620 Air, 1 adiabatic saturation of, 2. 22 atmospheric, 1 ' blades, 541 changes, 46, 124 change measurements, 771 chemical vitiation of, 45 circulation in drying, 625 classification of, impurities, 77 cleaning devices, 505 A.S.H.V.E. code, 507 classification, 508 cooled condenser, 441 ' ' Air, (continued) cooling, 443 . cooling effect of, 74 dehumidification, 487 with washers, 493 - density, 3 distribution, 529 for cooling, 384 ' for furnace systems, 367 for heating, 383 railway car, 586 unit conditioners, 420 dry. 1. 777 ' * , drying agents, 31, 36 activated alumina, 37 aluminum oxide, 37 calcium chloride, 41 charcoal, 38 lamisilate. 38 . lithium chloride, 41 silica gel, 38 silicon dioxide, 38 duct design, 543 elimination, 289 enthalpy, 22 excess, 161 exhaust hood flow, 610 flow, 543 _. flow resistance of coil, 469 horsepower, 517 humidification, 487 ' . leakage, 117 loudness chart, 538 measurement of, movement, 767 - measurement of natural flow, 646 measuring nozzle, 768 ' measuring orifice, 768 ' minimum outdoor supply, 46 movement, 45, 73 outdoor, 46 particles. 77 - sizes, 78 physical impurities in, 48 pollution, 77 primary, 163 - properties, 3 quality of, 45 saturated, 5, 780 secondary, 162 . space conductance, 89 specific heat of dry, 5 specific volume, 3 X ALPHABETICAL INDEX TO TECHNICAL DATA SECTION Air (continued) standard, 780 sterlizing, 49 . supply opening, 536 theoretical, requirements for fuels, 158 total heat, 22 traps, 284 velocities. 548 . washers, 487, 512 Air cleaner. 775 Air conditioning, 1, 45, 775 balancing, system, 542 comfort, 430 control systems. 658 fans. 523 in hospitals; 583 industrial 595 operating methods, 445 railway. 585 . residence control system, 666 . in treatment of disease, 573 units. 411 Air washer. 775 Airplane propeller fan, 519 Alcohol thermometers, 763 All year system control, 658 Allergic disorders, 579 apparatus, 580 asthma symptons, 580 hay fever symptoms, 580 ` Alternating current motors, 671 Alternating receivers, 285 Aluminum oxide, 37 Ammonia, 32 Anemometer, 769. 775 deflecting vane. 769 heated thermometer, 769 hot wire, 769 .propeller, 770 revolving vane. 770 Aneroid barometer, 766 Anesthetics properties, 574 firing methods for, 168, . stafidards. 170 ' Apartment houses plumbing fixture water demand, 761 stokers, 204 storage tank size, 756 . Area of circles, 792 A.S.H.V.E. codes and standards, 790 Asthma, 506 Atmospheric air, 1 conditions for industrial processes, 595- pressure, 775 water equipment, 493 v make-up water, 503 w * sizes, 497 winter freezing, 503 Atomization, 491 Atomizing humidifiers, 482 Attic fans. 411. 427 cost, 428 location, 428 ' types, 428 temperature, 129 . Automatic control, 649 (see Controls) fuel appliance control, 664 fuel burning equipment, 199 domestic oil burners, 210 gas-fired appliances, 217 mechanical stokers, 199 ' return traps, 285 . temperature control, 740 valves, 344 Auxiliary heat sources, 135 Awnings, 150 Axial flow fans, 515 ' B Babcock's formula for steam flow, 726 Back draft diverter, 196 Bacteria, 77 Baffle, 775 . Barn ventilation, 647 Barometer, 765 Biochemical reactions, 602 Bituminous, (see Coal) firing methods for, 170 Black body, 684, 717 Blast. 775 Body black. 717 human, surface area, 716 losses, 716 mean surface temperature, 717 . ' Boiler, boilers, 239, 775- capacities, 240 v cast-iron, 239 chimney sizes, 191 cleaning. 254 combustion rates, 240 connections, 252, 300 efficiency, 246 electrode, 710 erection, 253 estimated design load, 246 estimated maximum load, 246 fire box, 241 '' fire tube, 240 fittings, 252 furnace design, 242 gas-fired, 218, 241 grate area, 249 heat transfer rates, 244 heating, 239 . heating surface, 243, 775 horsepower, 245, 776 hot water, 239 storage allowance, 760 supply load, 247' insulation, 256 magazine feed, 241 maintenance. 253 oil burner, 241 operation, 253 output, 245 performance curves, 248 physical limitations, 251 piping tax, 247 radiation load, 247 - . ' rating codes. 244 selection of, 246 space limitation, 251. v steam, 239 steel. 240 testing codes, 244 - warming-up allowance, 247 Boiler burner units, 213 . Booster fans, 362 , Bourdon gage, 766 Boyle's law, 7 Brine cooling, 443 i British equivalent temperature,-717 British thermal unit, 776 Bronchitis, 48, 81 Bucket traps, 285 . Building load factors, 237 Building materials . heat transfer through, 773 noise transmitted, 564 Bulkeley psychrometric chart, 26 Burner, burners _ gas, control, 664 ' oil, control, 664 . By-pass, 776 air conditioning systems, 378 XI HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 c Calcium chloride, 41 Calorific value, 158 of coals, 167 of fuel elements, 158 of gaseous fuels, 175 of oil. 173 Calorie, 776 . Calorimeter, 159 Capicitor type motors, 672 Capillary moisture, 623 Carbon dioxide, 35, 45, 158 air change measurement, 771 Carbon monoxide, 158 from automobiles, 81 from chimney gases, 81 garage, 648 measurement, 774 Carbon partide9. 77 Carnot cycle, 435 Cast ferrous pipe, 328 Cast-iron boilers. 239 Ceiling temperature. 130 Chimneys (continued) for gas heating, 196 gas temperature, 184 performance chart, 186 Cheek temperature, 54 Cinder, dnders, 77, 83 catchers. 514 Circumferences of drcles. 792 City gas, (see Gaseous fuels) Climatic conditions, 132 Cloth filters, 616 Coal burner control, 665 . burning furnace, 364 . classification of, 166 dustless treatment of, 173 , estimating consumption, 236 firing of, 82 maximum carbon dioxide values, 163 pulverized, 172 sizes, 170 soot, 177 theoretical air requirements. 161 Coefficient of performance, 435 Central air conditioning systems, 377 blow through, 378 by-pass, 378 classification, 377 cooling coils, 467 cooling load calculations, 382 design of, 380 example calculated, 389 heating calculations, 381 reheating. 380 residential, 378 selection of equipment, 386 zoning, 389 Central fan heating, 707 Central fan systems, 776 . control, 654 Centrifugal compressors. 431 fans, 515 separators, 512 Charcoal. 38 Charles' law, 7 . Chart - air flow loudness. 538 Bulkeley psychrometric, 26 chimney performance, 186 coal fuel burning rate, 226 comfort, 61 _ economical thickness of insulation, 702 effective temperature, 63 ' friction of air in pipes, 546 fuel oil heating values, 632 gas fuei burning rate, 228 heat loss from bare iron pipes, 689 - heat loss from magnesia covered pipes, 690. 692, 693 hot water friction beads, 316 humidity, 626 lithium chloride temperature pressure, 31 . noise reduction. 570 oil fuel burning rate, 227 room absorption, 539 silica gel temperature pressure, 39 . thickness pipe insulation prevent sweating, 699 Check valves, 344 Chemical reactions, 602 Chemical vitiation of air, 45 Chimneys, 179 boiler sizes, 191 - characteristics of, 182 coeffident of friction, 184 construction details, 195' determining sizes, 187 effect, 776 furnace size, 191 Coefficients of transmission, 86. 776 doors, 113 '. floors and ceilings, 107 frame construction, 104 glass walls, 113 masonry walls, 100 roofs, 110 skylights. 113 . windows, 113 ' Coil, coils, 459 air flow resistance, 469 applications, 467 arrangement, 460 booster, 378 capadty, 473 construction, 460 cooling, 462 direct expansion, 463 flow arrangement, 466 heat transfer, 469 heating, 462 performance, 470, 474 primary surface, 461 reheating, 378 secondary surface, 461 selection. 482 steam, 462 water, 462 Coke dassification of, 168 estimating consumption, 236 firing methods for, 172 maximum carbon dioxide values, 163 petroleum, 168 Coke oven gas, (see Gaseous fuels) Collectors, 615 Combustion, 157 draft, 192 . drying, 627 efficiency of stoker, 209 gas analysis, 773 in gas-fired units, 220 gas constants, 631 heat of, 159 - of gaseous fuels, 176 of oil. 173 with oil burner, 214 with various stokers, 207 Comfort, 45* chart, 61 line, 776 zone, 776 average, 776 extreme,. 776 xil ALPHABETICAL INDEX TO TECHNICAL DATA SECTION Compartment drier, 620 Compound wound motors, 669 Compressors, 431 centrifugal, 431 control, 447, 667 reciprocating, 431 rotary, 431 steam jet, 432 Concealed heaters, 263 Concealed radiation, 776 Condensation in buildings, 92 meter, 731, 735 pumps, 280 rate, 289 return heating systems. 274 Condensers air cooled, 441 design data, 498 evaporative,'423, 443 water cooled, 442 Conductance, 776 air space, 98 with aluminum foil, 98 with non-metallic paint, 98 surface coefficient, 98 Conduction, 49, 776 electric heaters, 706 solar heat, 147 . Conductivity, 776 building boards, 97 building constructions, 98 insulating materials, 691 insulation blankets. 96 loose-fill insulation, 96 masonry materials, 94 plastering materials, 97 * rigid insulation, 97 roofing construction, 97 ' semi-rigid insulation, 96 v woods, 99 Conductor, 776 heat, 776 Constant relative humidity line, 776 Constant speed motors, 670 Control, controls all year systems, 658 . automatic, 649 fuel appliances, 664 temperature, 740 central fan systems. 654 cooling cycle, 657 cooling units, 661 dew-point, 658 direct current motor, 679 domestic hot water supply, 666 draft, 181 effective temperature, 658 of electric motors, 669 electric systems, 652 of electrical heating, 713 equipment for motors, 677 fan volume. 525 gas burner, 664 gas-fired units. 220 graduated-acting, 653 . of heat losses. 715 heating cycle. 654 humidity, 651 railway cars, 588 industrial process, 668 for mechanical furnace systems, 369 modulating. 653 multi-speed motor, 680 oil burner, 217, 664 pilot, 678 pneumatic systems, 652 positive-acting, 652 pressure, 651 rate of biochemical reactions, 602 rate of chemical reactions, 602 Controls (continued) rate of crystallization, 603 refrigeration equipment, 667 of regain, 598 of relative humidity. 657 residential systems, 665 roof ventilators, 643 room, 653 self-contained systems, 652 6ingle-phase motor, 682 single thermostat, 653 . slip ring motor, 681 sound,561 squirrel cage motor, 679 stoker, 210, 665 temperature, for railway cars, 588 three-wire motors, 678 two position, 652 two-wire motor, 678 unit heater, 661 unit systems, 660 '. unit ventilators, 662 vacuum pump, 283 * valves, 303, 651 vibration from machine mountings, 565 zone. 654 Convection, 715, 776 electric heaters, 707 Convectors, 776 (see Gravity convectors) connections, 304 Conversion equations, 785 Coolers. 443 Cooling of air, 443 for air conditioning units, 413 air processes, 429 of brine, 443 coils, 462 cycle control, 657 efficiency, 499 evaporative. 429, 455 load. 141 methods, 429 ponds, 499 , spray, 429 surface, 429 towers, 423, 501 units, 424 defrosting. 426 ratings. 426 . types of. 425 of water, 443 ' Copper elbow equivalents, 318 pipe, 328 tube sizes, 315 ' Corrosion, 346 industrial exhaust systems, 617 Cost of railway air conditioning, 592 Crystallization, 603 Cyclones. 512 Cyclone collector, 615 Cylinder drier, 620 design, 630 ` . . D Dalton's law, 1 Dairy barn ventilation, 647 Damper, dampers, 368, 542 splitters. 368 squeeze, 368 volume, 368 Damper motors. 651 Decibel. 561. 776 Deflecting vane anemometer, 769 Degree-day, 776 base temperature, 231 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Dehumidification by absorption. 430 by adsorption. 430 for air conditioning units, 413 methods, 429 processes, 430 Dehumidifier, dehumidifiers, 378, 487 Dehumidify, 777 Demand factor, 738 Density, 777 '' of air, 3 lithium chloride solutions, 42 Design estimated load, 777 Dew-point control, 658 . . relation to relative humidity, 10 temperature, 3, 777 Dichlorodifluoromethane, 33 Direct current motors, 669 - Direct-expansion coils, 463 Direct humidification, 491 . Direct-indirect heating unit, 777 Direct radiator. 777 (see Radiaior) Direct return system, 312, 777 Dirt pockets, 310. Disc fan, 515 Disease treatment, 573 Distillate, (see Fuel oil) Distillation temperature, 174 . Distribution of air, 529 (see Air distribution) Distribution factors in cooling, 534 in heating, 536 - District heating, 725 conduits for piping. 727 control, 733 manholes, 727 ' rates, 737 . utilization, 739 Diversity factor, 738 ,. Domestic water supply, 741 . Doors, 113 air leakage, 121 . for natural ventilation, 641 Down-feed riser, 777 " steam, 777 Draft, 179 available, 182 control, 181 head, 777 side outlet enclosure, 777 top outlet enclosure, 777 localized, 52 loss through boiler, 192 mechanical 180 natural, 179 regulation, 165 requirements, 165 theoretical, 182 through breeching, 193 through economizer, 194 . _ - Driers, 621 adiabatic, 621 agitated. 620 compartment, 620 cylinder, 620 drum, 620 festoon, 620 high temperature, 635 induction, 620 rotary, 620 spray, 620 tower, 620 tunnel, 620 vacuum, 620 Drip, 777 Drum drier, 620 Dry air. 1, 4, 777 Dry-bulb, temperature, 777 . thermometers, 75 Drying, 601, 619 agents. 31, 36 air circulation, 625 combustion, 627 by conduction. 621 by convection, 621 equipment for, 625 estimating methods, 637 factors influencing, 623 fans for. 524 humidity in, 624 humidity chart, 626 mechanism of, 622 methods, 619 moisture in, 623 oven, 627 by radiation, 619 temperature in, 624 time of, 628 varnish, 602 ventilation phase, 633 ' ' Duct, ducts. 369 air velocities, 614 . air velocity measurements. 770 '- circular equivalents, 549, 550, 551 . construction, 613 construction details, 557 . dampers, 368, 542 design, 612 expanding, 536 . heat losses from, 694 insulation. 683 . . lagging, 569 '' . lining of, 569 . lining factor, 570 main trunk, 553 ' . noise transmitter, 564 recirculating, for gravity furnace systems. 353 velocities through, 371 weight of galvanized, 559 Duct sizing, 548 ' equal friction method, 548, 553 - friction loss method, 548, 553 general rules, 548 'velocities, 548 . velocity method, 548, 553 Dust, 48, 77. 83, 506, 777 concentrations, 80 . control of, 80 determination, 772 . Hill counter, 773 nature's, catcher, 84 removal requirements, 506 resistance, 615 . . Smith-Greenburg impinger, 773 thermal precipitation, 506 Dustless treatment of coal, 173 Dynamic equilibrium. 2 Dynamic head or pressure, 777 (see Total Pressure) Dynamic losses, 544 E Economizer; 731 * Effective coil temperature, 476 . Effective temperature, 54, 60, 70, 129, 658, 777 (see Temperature) ` chart, 63 ' control of, 658 Elbows pressure loss in rounds, 544 pressure loss in square, 544 . Electric, electrical * boilers, 709 central fan heating, 707 control, 713 . heater, 706 heating, 705 .. XIV ALPHABETICAL INDEX TO TECHNICAL DATA SECTION S Electric (continued) Fans (continued) | . heating element, 706 iI hot water heating, 710 * ' \V ' .. ' :. industrial heating, 712 - motors, 135, 669 off-peak heating, 710 power problems, 714 *' power for railway cars, 589 Eplercectriipcitactoonrst,ro5l1s2ystems, 652 ' EEExllienmrsuectinessitnrisaitosaimvtdhotioeetrhya,re,bt7peao90lrt0ias6ilnet,egr7s,,0,777410809 8 factor, 721 values, 684 Enclosed radiators, 261 Enthalpy, 777 of air, 22 Entropy, 777, '; of refrigerants, 32 - Equilibrium moisture, 623 Equivalent evaporation, 777 length of run, 292 Estimated design load, 777 Estimated maximum load, 778 Eupatheoscope, 723, 773 Evaporation, 49 equivalent, 777 booster, 362 central system, 776 centrifugal, 515 characteristic curves. 517 designations, 527 disc, 515 drive arrangement, 526 for drying, 524 for dust collecting, 525 , efficiency, 517 furnace system, 778 (see Warm air healing system) for industrial exhaust systems, 617 mechanical efficiency, 517 motive power, 527 ' . multiple blade, 524 - outlet velocity, 523 performance, 515 propeller, 515 radial flow, 515 selection of, 522 static efficiency, 517 ' system characteristics, 521 tip speed, 523 ventilating, 523 volume control, 525 Festoon drier, 620 Fever therapy, 578 equipment for production of, 578 . high temperature hazards, 579 Fiber saturation point, 623 Film conductance, 86 Filters, 366, 508 ; t i: . j ' , '' Evaporative, condenser, 423, 443 cooling, 429, -455 regulation, 53 Evaporators* -443 ` Excess air, 161 ' Exhaust opening, 529 . Exhaust systems, 605 classification of, 605 collectors, 615 . corrosion protection, 617 design procedure for, 606 ducts for, 612 efficiency of, 617 fans for, 525 . . hoods for, 609 air flow in, 610 axial velocity formula, 609 . chemical laboratory, 612 large open, 611 ` velocity contour, 609 lateral, 611 . resistance of, 616 selection of fans, 617 selection of motors, 617 spray booth, 612 . . suction requirements, 607 Expanding duct, 536 . Expansion . bends, 334 ` tanks, 325 / Exposure factors, 134 Extended heating surface, 778 (see Heating surface) Extended surface heating unit, 778 F for air conditioning units, 414 automatic, 510 cloth, 513. 616 dry air, 511 dust holding capacity, 509 efficiency, 507 resistance, 509 . . viscous type. 508 . Fire box boilers, 241 Fire tube boilers, 240 Fittings, 327 (see Pipe) areas of flanged, 691 copper, 328 dimensions of, 339, 340, 341 . pipe allowances, 746 . thread connections, 338 types of, 336 Flame temperature, 160 Flanges, 343 Flash point oil temperature, 174 Flexible mountings, 565 Float traps. 284 Floor heating, 718 Floor level temperature, 131 Flow meter, 735 Flow of steam in pipes. 288 ' Fogs. 77 Force, 778 Friction factor, 185 Friction losses. 544 . air in pipes, 546 . rectangular ducts, 545 round pipe, 545 - Fuel, fuels, 157 analysis, 160 ignition temperatures. 158 seasonal efficiency, 238 unit consumptions, 230 utilization, 223 degree-day method, 229 heat loss method, 224 Fuel oil . . , ' . ' _ . Fan, fans, 366, 515 A.S.H.V.E, code for, 518 air conditioning, 523 air horsepower, 517 airplane propeller, 519 axial flow, 515 carbon residue, 174 classification of, 173' ' combustion of, 173 grade of, 174 . . maximum carbon dioxide values, 163 theoretical air requirements, 161 viscosity, 174 XV HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Fumes, 77, 778 toxicity of, 81 Furnace, furnaces, 364, 778 baffling, 365 boiler design, 242 capacity, 355 casings, 364 . chimney sizes, 191 design for stokers, 208 . fuel combustion, 163 gas-fired, 218 '- gravity systems, 349 mechanical systems. 349 volume, 173, 778 G Gage Bourdon, 766 draft. 766 hook, 766 pressure. 766, 778 vacuum, 766 Garage, gas heaters, 219 ventilation, 647 Gas. gases, burner control, 664 burning furnace, 364 cleaning of, 512 combustion constants, 631 estimating consumption, 233 flue, analysis, 773 ' heat content,' 633 limits of inflammability, 79 threshold limits of, 617 toxic. 46 toxidty of, 81 - Gas-fired appliances, 217 . . boilers, 218, 241 chimneys for, 198 combustion process, 220 controls. 220 conversion burners. 220 furnaces, 218 garage heaters, 219 . orsat test, 220 parlor furnaces, 219 radiant heaters, 219 radiators. 219 ratings for, 221 space beaters. 219 warm air radiators, 219 ' Gaseous fuels classification of, 175 combustion of, 176 flame temperature, 176 maximum carbon dioxide values, 163 products of combustion, 175 properties of. 176 theoretical air requirements, 161 Glass air leakage, 120 . solar heat transmitted, 148 walls. 113 Globe, thermometer, 75, 724, 773 ' valves, 344 Grate area, 249, 778 Grate stokers, 199 Gravitational settling chambers, 512 Gravity convectors, 257, 263 A.S.H.V.E. code. 265 correction factors, 265 effect of superheated steam, 259 heat emission, 257 heating up. 261 raloHinn Gravity furnace systems, 349 Capacity, 355 design procedure, 349 leader pipe sizes, 350 proportioning wall stacks, 352 recirculating ducts, 353 recirculating grilles, 353 register selections,.353 return connections, 355 ' warm air, 778 (see Warm air heating systems) Grille, grilles, 529 (see Registers) air velocity measurement, 770 dampers, 542 deflection, 536 ejector effect of, 541 locations, 530 for mechanical furnace systems, 367 noise, 531. 572 selection of, 540 sound control, 533 types of, 541 velocity, 548 Guarded hot plate, 773 Gun type oil burners, 211 H Hay-fever, 77, 506 Health. 45. 80 . Heat, 778 auxiliary sources, 135 of combustion, 159 content of gases, 633 content of refrigerants, 32 emission of appliances, 153 emission of occupants. 150 generated by motors, 153 infiltration equivalent. 125 latent, 31. 49, 57 of the liquid, 778 loss, 127 ' from bare copper pipes, 686 from bare steel pipes, 686 by convection. 717 ` from ducts, 694 by evaporation, 716 insulated pipes, 692 ` by radiation, 717 mechanical equivalent of, 779 outside air, 151 produced by cow, 647 . pump, 712 rate of production, 716 removal by natural ventilation, 644 -residence, loss example^ 137 ' room load ratios, 387 sensible, 31, 49, 57 . solar. 143 transfer, 85 ' of coils, 469 surface coils, 459 a through building materials, 773 transmission, 143 coefficients, 85, 127 by convection, 683 by free convection, 685 by radiation, 683 utilization, 223 Heat gain, 141 appliances, 152 electrical heating equipment, 152 gas burning equipment, 152 glass, 148 insulated cold pipes, 698 for insulated ducts, 699 for insulated pipes, 699 ALPHABETICAL INDEX TO TECHNICAL DATA SECTION Heat gain (continued) latent, 143 light. 153 occupants, 150 outside air. 151 people, 150 roof, 143 sensible, 143 . A steam heated equipment, 15-5 wall, 143 Heater electric, 706 unit. 394 Heating, v for air conditioning units, 412 boiler surface, 243 boilers. 239 coils, 462, 758 cycle control. 654 design temperature, 134 district, 725 , domestic water supply. 710 floor, 718 fuel oil values, 632 garage. 648 load, 127 medium, 778 . radiant, 715 surface, 778 extended, 778 prime. 778 square foot of, 780 . value of gas, 135 High duty humidifiers, 492 ^ spray. 492 High pressure steam, 302, 731 Hill dust counter, 773 Homogeneous materials, 88 Hoods, 609 ' Hook gage, 766 Hospitals,. . . air conditioning, 583 noise level, 563 operating rooms, 573 air conditions, 574 reducing explosion hazard, 573 sterilization of air, 576 ventilation requirements, 574 plumbing fixture water demand, 761 Hot water boiler allowances, 760 ' boilers, 239 .... _flt consumption in buildings, 761 demand for plumbing fixtures, 761 ^Aman4t/ oamnlV flVRlCJU* 752 heaters, 757 heating coil, 758 storage capacity, 760 Storage tank sizes, 756 supply, 755 ` . Hot water, domestic, boiler load, 247 boilers, 242 , control- of, 666 direct heaters, 242 indirect heaters, 242 lot water heating systems, 311, 778 direct return system, 312 elbow equivalents, 318 friction heads, 316 gravity pressure heads. 320 installation details, 326 mechanical circulators, 312 orifice friction heads, 322 pipe sizes, 312 reversed return system, 312 sintami rtf nininff. 311 ^ . ' Hot-wire anemometer, 75, 769 Hotel, hotels, hot water consumption, 761 plumbing fixture water demand, 761 Household stokers, 202 Human body, adaptation, 50 to cold conditions, 55 to hot conditions. 53 heat emission. 150 heat gain. 150 odors. 46 ` temperature, 49 weight loss, 54 zone of body cooling. 51 zone of evaporative regulation, 50 Humidification, 373 Humidifiers, 487 atomizing, 492 high duty, 492 unit, 409 Humidify, 778 Humidifying, for air conditioning units, 412 efficiency. 490 Humidistat. 369, 779 Humidity, 8, 45. 779 absolute, 8. 775 constant relative, line, 776 control, 651' - for railway cars, 588 for drying, 624 . for industrial processing, 596 influence of, 71 - measurement of, 772 permissible relative,'92 relative, 9 specific, 8 Hygrostat, (see Humidslat) I Ice refrigeration control, 667 systems. 456 Immersion thermostat, 650 Impulse traps. 285 Impurities. 77 Inch of water, 779 Indirect water heater, 758 Induction drier, 620 Industrial . ' " air conditioning, 595 electric heating, 712 exhaust systems, 605 {see Exhaust systems) process control, 668 processes, 595 humidities for processing, 596 temperatures for processing, 596 Industrial buildings, - hot water consumption, 761 noise level, 563 plumbing fixture water demand, 761 Indirect heating units, 305 Infiltration, 117, 128 heat equivalent, 125 through shingles, 119 through walls. 118 through windows, 120 Inflammability of gases, 79 Insertion thermostat, 650 Inside temperature, 127, 129 Instruments, 763 Insulation, 714, 779 boiler, 256 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Insulation {continued) duct, 683 low temperature, 697 pipe, 683 conductivity, 691 economical thickness, 701 to prevent freezing, 700 underground, 703 of vibration, 565 Intermittently heated buildings, 135 Interstitial condensation, 92 Ionization, 48 Iron elbow equivalents, 318 Isobaric, 779 Isothermal, 779 Kata-thermometer, 769 Lamisilate. 38 Latent heat, 31, 49, 57 of water, 30 Laws of thermodynamics, 779 leader pipe sizes, 350 Leakage of air, 117 Light heat gain, 153 Lignite, (see Coal) Liquid - adsorbents, 40 heat of, 778 Lithium chloride, 41 systems, 452 Load, cooling, 141 factors, 238, 737 heating, 127 * Loudness, 562 level, 537 ' M Magazine feed boiler, 241 Manholes, 727 .. Manometer, 779 Manufactured gas, {see Gaseous fuels) Mass. 779 Mb, 779 Mbh, 779 Mean radiant temperature, 67, 716 Mechanical circulators, 312 draft. 180 towers, 502 . efficiency, 517 equivalent of heat, 779 furnace systems, 363 air distribution. 367 automatic controls. 36 > cooling methods, 375 ducts, 369 fans, 366 filters, 366 heavy duty,' 373 humidification. 373 method of design. 369 motors, 366 sound control, 366 stokers. 199 Mercurial thermometers, 703 ' Metabolic, processes, 45 rate, 57 Metabolism, 49, 57 Meters . condensation, 731, 735 differential, 734 flow, 735 '. fluid, 734 Nicholl's heat, 773 orifice, 737 positive, 734 sound level, 562 vacuum condensation, 736 Venturi, 768 water disc, 747 . Methyl chloride, 34 Micromanometers, 767 Micron, 77, 505, 779 Microphone, 562 Mineral particles, 78 Mists, 77 Moisture, capillary, 623 content, 599 equilibrium, 623 ' hygroscopic, 623 Mol. 779 . Monofluorotrichloromethane, 36 Motors. 366 damper, 651 . heat generated, 153 - for industrial exhaust systems, 617 Motors, electric, 135, 669 adjustable speed, 670 adjustable varying speed, 670 alternating current, 671 capacitor type, 672 classification of, 674 compound wound, 669 constant speed, 670 control equipment for, 677 direct current, 669 . polyphase, 673 repulsion induction, 672 series wound, 669 * shunt wound, 669 . _ single phase, 672 . slip ring induction, 676 speed characteristics; 670 split phase, 673 squirrel cage induction, 673 synchronous, 677 varying speed, 671 Mouth spray infection, 47 Multiple blade fans, 524 . N Natural draft, 179 towers, 501 Natural gas, (see Gaseous fuels) ' Natural ventilation, 639 Nature's dust catcher, 84 ' Nicholl's heat meter, 773 Nitrogen, 157 Noise, 561 acceptable levels. 563 apparatus for measuring, 562 coefficients, 572 created by equipment, 564 fan. 523 kinds of- 564 levels, 562 reduction, 570 transmitted through ducts, 569 unit of measurement, 561 xvui ALPHABETICAL INDEX TO TECHNICAL DATA SECTION O Occlusion of solar radIatlon^*82 Odors, 46 human body. 46 Oil, burner control. 664 burning furnace, 364 estimating consumption, 234 Oil burners. 210 boiler, 241 boiler settings. 214 combustion adjustments, 216 - commercial, 213 controls, 217 furnace design, 215 gun type, 211 orsat test. 216 pot type, 211 rotary. 211 . One-pipe supply riser, 779 One-pipe system, hot water. 779 ' steam 779 Operating rooms,-573 Operative temperature. 51 Optical pyrometers, 765 Organic matter, 45 Orifice, friction heads, 322 heating systems, 278 meter, 737 Orsat apparatus, 773 Oscillatingventilator, 643 Outlet velocity for fans, 523 Outside temperature, 127, 131 Overhead system, 779 Oxygen, 45, 157 t Oxygen therapy, 581 chambers,' 582 tents. 581 Ozone, 48 ' P Panel radiator. 779 . Panel wanning. 779 Pathogenic organisms, 48 - . Perforated ceiling, 542 Petroleum coke, 168 . - Petterson-Palmquist apparatus, 771 Phon, 561 ` Physiological principles, 45 ' Pilot thermostat, 655 Pipe, piping, 327 anchoring. 335 * capacities, 295 cast ferrous, 328 -. coil connections, 306 conduit, 727 copper, 328 corrosion, 346 dimensions, 328 equivalent length of run, 292 expansion, 332 flanges, 343 flexibility, 332 hangers, 336 insulation, 683 economical thickness, 701 Pipe {continued) to prevent freezing, 700 underground, 703 maximum velocity, 290 ' pressure drop, 290 refrigerant sizes, 444 sizes, 290. 294. 726 effect of reaming, 293 effect of smoothness, 293 Hartford return connection, 300 for hot water heating systems, 312 indirect heating units, 305 one-pipe gravity air-vent system, 294 one-pipe steam systems, 291 orifice systems, 299 for steam heating systems, 287 sub-atmospheric systems, 299 two-pipe gravity air-vent system, 298 two-pipe steam systems, 291 two-pipe vapor systems, 298 vacuum systems, 299 supports, 336 tax, 247 thermal expansion, 335 thread connections, 338 . threads, 335 ' tunnels, 730 water supply, 741 weights, 332 welded, 327 wrought-iron, 327 wrought-steel, 327 Pipe coils, 257 heat emission, 259 wall, 258 Piston displacement vacuum pumps, 283 Pitot tube. 767 . . Plenum chamber, 780 Plumbing fixture flow, 743 . Pneumatic control systems, 652 Pneumonia. 48 Pollen, 77, 505 Pollution, 77 Polyphase motors, 673 Pot type oil burner, 211 Potentiometer, 780 Pour point oil temperature, 174 Power, 780 - fan motive, 527 Precipitators, 512 Premature infant nurseries, 576 air conditions. 576 equipment, 577 humidity, 576 Pressure v absolute, 775 atmospheric, 775 barometer, 766 controllers, 651 gages, 766 loss through water meters, 747 measurement, 765 reducing valves. 302 suction, hoods, 608 velocity, 782 Prime surface {see Heating surface) Primary air, 163 Propeller anemometer, 770 Propeller fan, 515 Psychrometer, 75, 780 . Pulse rate, 54. Pulverized coal, 172 . Pumps, 280 , condensation, 280 - piston displacement vacuum, 283 vacuum. 281 ' Purchased steam,' 725 . Pyrometers. 765, 780 optical, 765 radiation. 765 XIX HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 O-R Radial flow fan, 515 Radiant electric heaters. 706 Radiant gas heaters, 219 Radiant heating. 715 application methods, 718 calculation principles.' 720 measurement. 723 physical factors, 715 physiological factors. 715 Radiant temperature, 716 Radiating surface, of copper tubing, 6S8 of pipe, 688 Radiation. 49, 715, 780 black body, 721 boiler load, 247 solar, 145 Radiation pyrometers. 765, Radiator, radiators, 257, 780 A.S.H.V.E. code, 265 concealed, 262, 776 condensation rate, 261 connections, 304 correction factors, 265 direct. 777 effect of paint, 259 . effect of superheated steam, 259 ' enclosed, 261 gas-fired, 219 gas warm air, 219 heat emission, 257 heating effect, 260 heating up, 261 output of, 258 panel. 779 recessed, 780 room temperature gradients, 260 selection, 264 tube (or tubular), 781 types of, 257 valves, 269 Rag-weed, 77 Railway air conditioning, 585 ,, air cleaning. 586 air distribution. 586 cooling equipment, 587 ' cost of, 592 humidity control, 588 power supply, 589 steam heating, 587 temperature control, 588 Receiver, 735 Reciprocating compressors. 431 Rectal temperature. 54 Reducing pressure valves, 344, 731 Reflective surfaces, 90 Refrigerants, 31, 780 ammonia, 32 carbon dioxide, 35 dichlorodifluoromethane, 33 feeds, 464 methyl chloride, 34 monofluorotrichloromethane, 36 water, 37 Refrigerating effect, 435 Refrigeration, 429 ` compression systems, 430 control of equipment, 667 mechanical, 432 characteristics of systems, 439 coefficient of performance, 435 practical cycle, 435 refrigerating effect, 435 theoretical cycle, 433 Refrigeration (continued) pipe sizes, 444 reversed cycle, 455, 712 ton,435 day of, 781 Regain, 598 of hygroscopic materials, 600 Register, registers, 529 (see Grilles) air velocity measurement, 770 dampers, 542 ' deflection, 536 ejector effect of, 541 for gravity furnace systems 353 ' locations, 530 for mechanical furnace systems, 367 noise, 531, 572 selection of. 540 sound control, 533 types of, 541 velocities through, 371 . velocity, 548 Relative humidity, 9, 780 (see Humidity) measurement of, 772 requirements for premature infants, 71 Relays. 651 Remote air conditioning units, 415 Repulsion induction motors, 672 Research residence, 361 Residence. air conditioning control, 666 control systems. 665 * heat loss examples, 137 indoor humidity for, 66 indoor temperature for, 66 noise level, 563 plumbing fixture water demand, 761 storage tank size. 756 Resistance, 86 thermometers, 765 Resistivity. 86 Resistor, 706 Respiration, 46 Restaurants, hot water consumption, 761 noise level, 563 Return, air grille, 531 boiler connections, 300 capacity, 727 Hartford connection, 300 mains, 780 pipe capacities, 296 Reversed cycle refrigeration, 455. 712 Reversed return system, 312, 780 Revolving vane anemometer, 770 Ringetmann smoke chart, 774 Roof, solar radiation, 143 ventilator, 641, 780 Room, air'conditioners. 415 , control, 653 distribution factors, 534 thermostats. 650 '. Rotary, - compressors, 431 drier, 620 . oil burners, 211 Rotating ventilator, 643 ' S Sabins. 537 Saturated air, 5, 780 Saturating efficiency, 489 School, schools, indoor humidity for, 66 XX ALPHABETICAL INDEX TO TECHNICAL DATA SECTION Schools (continued)' indoor temperature for, 66 comfort line, 65 noise levels. 563 . plumbing fixture water demand, 761 Scrubbers. 488 Seasonal efficiency, 238 Secondary air, 162 Self-contained, - controlled systems, 652 unit, 411 Semi-anthradte, (see Cool) Sensible heat, 31, 49, 57 of water, 30 ' Separating traps, 284 Series wound motors, 669 Settling chambers, 512 Sheet metal gage, 613 Shunt wound motors, 669 Silica gel, 38 . systems, 451 Silicon dioxide, 38 Silicosis. 48 * Single phase motors, 672 Skylights, 113 . - for natural ventilation, 641 solar heat transmitted, 149 Sling psychrometer, 772 Slip ring induction motors, 676 Smith-Greenburg dust impinger, 773 Smoke. 77, 514. 780 abatement, 82 density measurement, 774 stacks, 514 Ringelmann chart, 774 tobacco, 46, 505 Smokeless arch. 780 Solar heat, 143 absorption coefficients. 148 effect of awnings, 150 intensity chart, 144 radiation factors, 147 radiation through walls, 145 through glass, 148 time tag, 148 - . transmission, 143 Solar radiation, building orientation, 68 occlusion of. 82 Solenoid valves, 651 Solid adsorbents, 37 Soot, 177 Sound, 561 ahsorber, 569 absorption, 537 control. 366. 533, 561 general problem of dbntrol,^662 level meter, 562 " Specific density,*3 Specific gravity, 3, 780 of oil. 173 Specific heat, 780 of dry air, 5 Specific humidity. 8 Specific volume, 780 of air, 3 Split phase motor, 673 Split system, 407. 780" Splitter dampers, 368 Spray cooling ponds, 500 . cooling tower, 501 distribution', 491 drier, 620 . equipment. 487 generation. 491 humidifiers, 492 type air conditioning unit, 419 Square foot of heating surface, 780 Squeeze dampers, 368 Squirrel cage induction motors, 673 Stack, stacks, 514, 643 ' height, 780 ` smoke. 514 Standard air, 780 ` Static, efficiency. 517 ' pressure, 517, 781 Stationary ventilator, 643 Steam, 1, 781 boiler connections, 300 boilers. 239 coils, 462 consumption for buildings, 237 distribution piping, 725 electric heating, 709 ' estimating, 236 heating systems, 267, 781 air line. 271 condensation return, 274 . corrosion, 346 drips. 307 gravity one-pipe air-vent, 268 gravity return, 267 gravity two-pipe air-vent, 271 mechanical return, 267 one-pipe vapor, 271 orifice. 278 piping for, 287 pressure drop, 270 radiator valves, 269 railway car, 587 sub-atmospheric, 276 two-pipe vapor, 272 vacuum, 274 zone control, 279 flow, 289 flow in pipes, 288 high pressure, 302 overhead distribution, 730 - pipe capacities, 295 properties of, 27 ; purchased, 725 requirements, 736 trap, 781 . utilization, 739 , velocity, 725 Steam jet, . compressors, 432 systems, 437 Steel boilers, 240 Steel pipe sizes, 314 Stefan-Boltzman formula, 683 Sterilizing air, 49 in operating rooms, 576 Stoker-fired units, 204 Stokers, 199 apartment house,>204 ' combustion adjustments, 209 combustion process. 207 controls, 210, 665 furnace design, 208 household, 202 t operating requirements for, 203 ' orsat test, 209 . over-feed flat grate, 199 over-feed inclined grate, 200 _ under-feed rear cleaning, 201 " under-feed side cleaning, 200 Storage, tank capacity, 760 tanks, hot water, 710 Store air conditioners, 415 Sub-atmospheric heating systems, 276 Sub-bituminous, (see Coal) firing methods for, 172 Submerged heating coil, 758 Summer, , comfort zone, 61 indoor conditions, 70 Superheat of refrigerants, 32 XXI HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Supply opening, 529 {.see Grilles and Registers) ceiling type, 542 . . selection of, 540 types of, 541 wall type, 542 Surface. condensation, 92 conductance, 86. 781 thermostat, 650 Sweat secretion, 53 Swivel joints, 334 Symbols for drawings, 787 . Synchronous motors, 677 Systems, of control, 652 hot water heating, 778 T Tank, tanks, expansion, 325 storage, sires, 756 water storage, 710 Temperature, 1, 45 absolute, 717 attic, 129 automatic control, 740 barn, 647 base for degree-day, 231 body, 49 . British equivalent, 717 ceiling, 130 cheek, 54 chimney gas, 184 control for railway cars, 588 dew-point, 3, 777 distillation, 174 dry-bulb. 2, 128, 142, 777 drying, 624 effective, 54, 60. 70, 129, 777 effective coil, 476 flame, 160 flash point, of oil, 174 floor level, 131 gaseous flame, 176 heating design, 134 ignition, for fuels, 158 for industrial processing, 596 inside. 127, 129 . mean radiant. 67, 716 measurement, 763 operative, 51 outside, 127, 131 pour point, of oil, 174 prematurely born infants, 65 rectal, 54 thermal interchanges, 49 wall, 70 water main, 494 well water, 496 wet-bulb. 2. 142, 498, 782 Temperature-entropy diagram, 435 Test instruments. 763 Test methods, 763 Therm, 781 Thermal, conductance, 86 conductivity, 86 interchanges of body, 49 resistance, 781 resistivity, 781 transmittance. 86 Thermocouple, 764 Thermometers, 763 alcohol, 763 dry-bulb, 75 globe, 75. 724, 773 Kata, 75, 769 . Thermometers (continued) mercurial. 763 resistance, 765 stem correction, 764 . ' Thermostat, thermostats, 369, 650, 781 immersion, 650 insertion, 650 pilot, 655 room, 650 surface, 650 Thermostatic traps, 285 . Tilting traps, 286 Time lag, 146 Tip speed for fans, 523 . Tobacco, drying, 601 smoke, 46, 505 - Ton of refrigeration, 435, 781 Ton day of refrigeration, 781 Total heat (see Enthalpy) of air, 22 Total pressure, 781 Tower drier, 620 Towers, make-up water, 503 mechanical draft,' 502 natural draft, 501 ' spray cooling, 501 winter freezing, 503 Toxicity of gases, 85 Transmission coefficients. 85 Transmittance of vapor, 92 . Trap, traps, 284 air, 284 - automatic return, 273, 285 bucket, 285 float, 284 impulse, 285 separating, 284 thermostatic, 285 tilting, 286 Treatment of disease, 573 Trunk ducts, 553 Tube, ' Pitot, 767 . radiation, 781 Tunnel drier, 620 Tunnels, pipe, 730 Turning members, 536 ' Two-pipe system, 781 ' . ` U Ultra-violet light, 48.-82, 576 Underfeed distribution system, 781 Underfeed stoker, 781 - Underground, ' conduits, 727 , pipe insulation, 703 Unit, units, 781 air conditioners, 41T application, 420 ` cooling, 413 costs, 427 '- dehumidifying, 413 filtering, 414 ' heating, 412 humidifying, 412 . rating basis, 423 types of, 415 ventilating,. 414 all year control, 663 control systems, 660 coolers, 411 defrosting. 426 ratings, 426 types of, 425 . ' XXII ALPHABETICAL INDEX TO TECHNICAL DATA SECTION Units (continued) , cooling control, 661 direct-indirect- heating, 777 electric heaters, 707 filters, 509 * heater, 393 application 401 ' capacity of, blow-through, 398 draw-through. 399 boiler capacity, 397 . connections, 304, 397 control, 661 ' direct-fired, 403 electric, 403 ratings, 396 turbine driven, 403 types of, 395 humidifiers, 393, 409 types of, 409 of noise measurement. 561 of refrigeration, 435 ventilator, 393 . applications, 407 capacities of, 405' control, 662 ratings, 404 specifications, 403 Up-feed system, 782 * V Vacuum condensation meter, 736 drier, 620 gage, 766 heating pumps, 281 ' ' controls, 283 heating systems, 274, 287, 782 Valves, 343 angle, 344 - automatic, 344 check. 344 control. 303, 651 globe, 344 pipe allowances, 746 reducing pressure, 302, 344, 731 . olenoid, 651 - Vapor, 77 . barrier, 93 heating systems. 782 limits of inflammability, 79 threshold limits of, 617 travel, 92 \ water, 1 , ' Varying speed motors, 671 Velocity. 782 head. 543 wind effects, 131 pressure, 782 ' Ventilation, 45. 782 for air conditioning units; 414 dairy farm, 647 fans, 523 . garage, 647 heat removal. 644 natural, 639 passenger car, 585 ' Ventilator, ventilators, oscillating, 643 roof, 641, 780 control, 643 rotating, 643 stationary, 643 unit, 403 window, 408 Venturi meter, 768 Vertical flues. 643 Vibration from machine mountings, 565 Viscosity of lithium chloride solutions, 42 Vital factors, 75 Volume, dampers, 368 furnace, 173 of refrigerants, 32 specific, 780 Volumetric efficiency, 436 ' W Wall,-walls, air leakage, 118 radiator, 258 solar radiation, 143 '' ' temperatures, 70 Warm air heating systems, 349, 363, 782 gravity, 349 mechanical, 363 ' Warming-up boiler allowances, 247 Washers. 512 Water. 1, 37 boiling point of, 30 ` coils, 462 composition of, 26 cooled condenser, 441 cooling, 443 equipment, 493 density of, 26 disc meters, 747 heating, 741 heating domestic supply. 710 main .temperature, 494 pressures, 30 properties of, 26 specific heat of, 30 . . , . supply piping, 741 down-feed risers.' 745 horizontal mains, 748 overhead distribution, 748 . up-feed risers, 746 vapor, 1 mean specific heat of, 7 . properties of saturated, 12 Welding, 327, 338 Well water refrigeration control, 668 . Well water temperature. 496 Wet-bulb temperature, 498, 782 (see Temperature) Wet return, 782 Wind, forces due stack effect, 640 ' forces in natural ventilation, 639 velocity and direction, 142 -' velocity effects, 131 . velocity selection, 122 < Window, windows, 113 air leakage. 120 for natural ventilation, 641 solar heat transmitted, 149 ' Winter comfort zone, 61 Wrought-iron pipe, 327 Wrought-steel pipe, 327 X-Y-Z Zone for air conditioning systems, 389 of body cooling, 51 control, 654 of evaporative regulation, 50 heating system control, 279 T ti si Chapter 1 AIR, WATER AND STEAM r Dalton's Late, Temperatures, Air Properties, Humidity, Rela tive Humidity, Specific Humidity, Relation of Dew-Point to Relative Humidity, Adiabatic Saturation of Air, Total Heat and Enthalpy, Psychrometric Chart, Properties of Water, Properties of Steam Af IR conditioning has for its objective the supplying and maintaining, in a room or other enclosure, of an atmosphere having a composition, t temperature, humidity, and motion which will produce desired effects upon the occupants of the room or upon materials stored or handled in it. Dry air is a mechanical mixture of gases composed, in percentage of volume, as follows1: nitrogen 78.03, oxygen 20.99, argon 0.94, carbon dioxide 0.03, and small ^mounts of hydrogen and other gases. !l Atmospheric air at sea level is given in percentage by volume as: Nj 77.08, Oj 20.75, water vapor 1.2, A 0.93, COs 0.03 and Hj 0.01. The amount of water vapor varies greatly under different conditions and is frequently one of the most important constituents since it affects bodily l comfort and greatly affects all kinds of hygroscopic materials. . DALTON'S LAW 'll It A mixture of dry gases and water vapor, such as atmospheric air, obeys Dalton's Law of Partial Pressures; each gas or vapor in a mixture, at a given temperature, contributes to the observed pressure the same amount that it would have exerted by itself at the same temperature had no other gas or vapor been present. If p = the observed pressure of the mixture and pit pi, pt, etc. = the pressure of the gases or vapors corresponding to the observed temperature, then ' p = p\ + pt + Pi, etc. (1) TEMPERATURES Air is said to be saturated at a given temperature when the water vapor mixed with the air is in the dry saturated condition or, what is the equiva lent, when the space occupied by the mixture holds the maximum pos sible weight of water vapor at that temperature. If the water vapor -I- 'International Critical Tables. 1i HEATING VENTILATING AIR CONDITIONING GUIDE 1940 mixed with the dry air is superheated, i.e., if its temperature is above the temperature of saturation for the actual water vapor partial pressure, the air is not saturated. The starting point of most applications of thermodynamic principles to air conditioning problems is the experimental determination of the drybulb and wet-bulb temperatures, and sometimes the barometric pressure. The dry-bulb temperature of the air is the temperature indicated by any type of thermometer not affected by the water vapor content or relative humidity of the air. The wet-bulb temperature is determined by a thermo meter with its bulb encased in a fine mesh fabric bag moistened with clean water and whirled through the air until the thermometer assumes a steady temperature. According to the theory of W. H. Carrier2, this steady temperature is the result of a dynamic equilibrium between the rate at which heat is transferred from the air to the water on the bulb and the rate at which this heat is utilized in evaporating moisture from the bulb. The rate at which heat is transferred from the air to the water is substantially proportional to the wet-bulb depression (t -- t'), while the rate of heat utilization in evaporation is-proportional to the difference between the saturation pressure of the water at the wet-bulb temperature and the actual partial pressure of the water vapor in the air (e1 -- e). Carrier's equation for this dynamic equilibrium is: e< - e t - t' B - e' 2800 - 1.31' (2) In the form commonly used, where (B - e') - <) e = ' -- 2800 - 1.3/' e = actual partial pressure of water vapor in the air, inches of mercury. e' = saturation pressure at wet-bulb temperature, inches of mercury. B = barometric pressure, inches of mercury. I = dry-bulb temperature, degrees Fahrenheit. <' = wet-bulb temperature, degrees Fahrenheit. (2a) The derivation of Equation 2 was based upon the theory, supported by extensive experiments with atmospheric air, that the wet-bulb tem perature and the temperature of adiabatic saturation (see page 22) are identical. Subsequent study and experiment3.4.*6 have shown that these temperatures are very nearly the same for air and water vapor mixtures in the proportions and temperature range of normal atmospheric air, but that they differ widely for mixtures of dry air and vapors other than water, and for air-water mixtures at high temperature or vapor content. It is now recognized that the wet-bulb temperature is influenced, not Rational Psychrometric Formulae, by W. H. Carrier (A.S.M.E. Transactions, Vol. 33, 1911. p. 1005). The Kvaporation of a Liquid into a Gas--a Correction, by VV. K. Lewis {Mechanical Engineering, September, 1933). 4Tbe Theory of the Psychrometer, by J. H. Arnold (Physics, July, September, 1933). The Deviation of the Actual Wet-Bulb Temperature frpm the Temperature of Adiabatic Saturation, by David Dropkin (Cornell University Engineering Experiment Station Bulletin, No. 23. July, 1936). 2' CHAPTER 1. AIR, WATER AND STEAM only by the rate of heat transfer by convection from air to wet-bulb, but also by the rate of heat conduction through the thin film of stagnant air that clings to the wet-bulb, and by the rates of outward diffusion of vapor through the air film and of convection of vapor away from the film. Thus, there is no theoretical foundation for the equality of wet-bulb and adia batic-saturation temperatures; rather, it is by mere chance that in atmos pheric air the ratio of the heat transfer and vapor transfer coefficients is such as to make these temperatures substantially equal. In accordance with current air conditioning practice, they are assumed to be equal in the psychrometric equations and chart presented in The Guide. Equation 2a may be used to determine the actual partial pressure of the water vapor in a dry air-water vapor mixture. Then, from Dalton's Law of Partial Pressures, Equation 1, it follows that the partial pressure of the dry air is (B -- e). If a mixture of dry air and water vapor, initially unsaturated, be cooled at constant pressure, the temperature at which condensation of the water vapor begins is called the dew-point temperature. Clearly the dew-point is the saturation temperature corresponding to the actual partial pressure, e, of the water vapor in the mixture. ' AIR PROPERTIES Density is variously defined as the mass per unit of volume, the weight per unit of volume, or the ratio of the mass, or weight, of a given volume of a substance to the mass, or weight, of an equal volume of some other substance such as water or air under standard conditions of temperature and pressure. The term specific gravity is more commonly used to express the latter relation but, when the gram is taken as the unit of mass and the cubic centimeter as the unit of volume, density and specific gravity have the same meaning. The term specific density is sometimes used to dis tinguish the weight in pounds per cubic foot; and as here used, density is the weight in pounds of one cubic foot of a substance. The density of air decreases with increase in temperature when under constant pressure. The density of dry air at 70 F and under standard atmospheric pressure (29.921 in. of Hg.) is approximately 0.075 lb (see Table 1), while that of a mixture of air and saturated water vapor at the same temperature and barometric pressure is only about 0.0742 lb. In the mixture the density of the dry air is 0.07307 and that of the vapor is 0,00115 lb (see Table 2). . In order to make comparison^of air volumes or velocities it is necessary to reduce the observations to a common pressure and temperature basis. The basic pressure is usually taken as 29.921 in. of Hg., but no basic tem perature is universally recognized. Common temperatures for this purpose are 32 F, 60 F, 68 F, and 70 F. Since 70 F is the most commonly specified temperature to which rooms for human occupancy must be heated, it is usually understood, when no other temperature is specified, that 70 F is the basic temperature for measuring the volume or the velocity of air in heating and ventilating work. The specific volume of air is the volume in cubic feet occupied by one pound of the air. Under constant pressure the specific volume varies inversely as the density and directly as the absolute temperature. 3 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Temperature Deo F Table 1. Properties of Dry Air0 Barometric Pressure 29.921 In. of Hg. Weight Pounds per Co Ft Ratio op Volume to Volume at 70 F Bto Absorbed bt One Cu Ft Dry Air per Deo F Cu Ft Drt Air Warmed One Deo per Btu 0 10 20 30 40 SO ' 60 70 80 90 100 110 120 130 140 150 160 180 200 220 240 260 280 300 350 400 450 500 550 600 700 800 900 1000 0.08633 0.08449 0.08273 0.08104 0.07942 0.07785 0.07636 0.07492 0.07353 0.07219 0.07090 0.06966 0.06845 0.06729 0.06617 0.06509 0.06403 0.06203 0.06015 0.05838 0.05671 0.05514 0.05365 0.05223 0.04901 0.04615 0.04362 0.04135 0.03930 0.03744 0.03422 0.03150 0.02911 0.02718 . 0.8678 0.8867 0.9056 0.9245 0.9433 0.9624 0.9811 1.0000 1.0189 1.0378 1.0567 1.0755 1.0946 1.1133 1.1322 1.1510 1.1701 1.2078 1.2456 1.2832 1.3211 1.3587 1.3965 1.4344 1.5287 1.6234 1.7176 1.8119 1.9064 2.0011 2.1893 2.3784 2.5737 2.7564 0.02077 0.02030 0.01986 0.01944 0.01905 0.01868 0.01832 0.01798 0.01765 0.01733 . 0.01702 0.01672 0.01643 0.01616 0.01589 0.01563 0.01538 0.01490 0.01446 0.01403 0.01364 0.01326 0.01291 ' 0.01257 . 0.01181 0.01114 0.01054 0.01001 0.00953 0.00908 0.00833 0.00769 0.00713 0.00668 48.15 49.26 50.35 51.44 52.49 53.36 54.44 . 55.62 56.66 57.70 58.75 59.81 ' 60.86 61.88 62.93 63.98 65.02 67.11 69.24 71.27 73.31 75.41 77.46 79-55 84.67 89.67 94.87 99.01 104.93 110.13 120.05 130.04 140.25 149.70 Compiled by W. H. Sevems, based on the instantaneous specific heats of air. The values for the heats and for the cubic feet warmed one degree are for the temperatures stated and are not true over a tempera ture range of more than one degree above or below the temperatures stated. 4 CHAPTER 1. AIR, WATER AND STEAM Table 2. Properties of Saturated AiRa Weights of Air, Vapor and Saturated Mixture of Air and Vapor at 29.921 In. of Hg. Temp Deo F Weight in a Cubic Foot op Mixture Weight of Dry Air Pounds Weight of Vapor Pounds Total Weight of Mixture Pounds Btu Absorbed Cubic Foot Sat. Am peb Deo F Cubic Feet Sat. Am Warmed One Deg ?ea Btu Specific Heat Btu per Pound op Mixture 0 0.08622 10 0.08431 20 0.08244 30 0.08060 40 0.07876 50 0.07692 60 0.07503 70 0.07307 80 0.07099 90 0.06877 100 0.06634 110 0.06361 120 0.06057 130 0.05712 140 0.05317 150 0.04863 160 . 0.04339 170 0.03733. 180 0.03033 190 0.02228 200 0.01298 210 0.00230 212 0.00000 0.000068 0.08629 0.000111 0.08442 0.000177 0.08262 0.000278 0.08088 0.000409 0.07917 0.000587 0.07751 0.000828 0.07586 0.001151 0.07422 0.001578 0.07257 0.002134 0.07090 0.002851 , . 0.06919 0.003762 0.06737 0.004912 0.06548 0.006344 0.06346 0.008116 0.06129 0.010284 0.05891 0.012919 0.05631 0.016092 0.05342 0.019888 0.05022 0.024384 0.04666 0.029700 0.04268 0.035932 0.03616 0.037286 0.03729 0.02078 0.02031 0.01987 0.01946 0.01908 0.01872 0.01838 0.01805 0.01775 0.01747 0.01721 0.01696 0.01675 0.01657 0.01642 0.01630 0.01624 0.01621 0.01624 0.01633 0.01649 0.01672 0.01818 48.12 49.24 50.33 51.39 52.41 53.42 54.41 55.40 56.34 57.24 58.11 58.96 59.70 60.35 60.91 61.35 61.58 61.6961.58 61.24 60.64 59.81 55.01 0.2408 0.2406 0.2405 0.2406 0.2410 0.2415 0.2423 0.2432 0.2446 0.2464 0.2487 0.2517 0.2558 0.2611 0.2679 0.2767 0.2884 0.3034 0.3234 0.3500 0.3864 0.4624 0.4875 Compiled by W. H. Sevems, based on the instantaneous specific heats of air. Table 3. Specific Heats of Dry Air8 Constant Barometric Pressure of 29.921 In. of Hg. Temperature Deo F Instantaneoub or True Specific Heat Temperature Range Deg F Mean Specific Heat -301.0 -108.4 32.0 212.0 392.0 752.0 1112.0 0.2520 0.2430 0.2399 0.2403 0.2413 0.2430 0.2470 ' 32 to 212 32 to 392 32 to 752 32 to 1112 ---------- ---- 0.2401 0.2411 0.2420 0.2430 --....... Compiled by W. H. Sevems. based on data given in the International Critical Tables. *5 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 4. Weight of Saturated and Partly Saturated Air3 Dry-Bulb Temp Deg F 28.5 Weight or Saturated Air roR Various Barometric and Htgromethic Conditions--Pounds per Curio Foot Barometric Pressure laches of Mercury 29.0 29.5 30.0 . 30.5 31.0 Increase In Weight Per 0.1 in. Rise in Barometer Approx. Average Increase in Weight Per Deg Wet-Bulb Depression 30 0.07703 0.07839 0.07974 0.08110 0.08245 0.08381 0.00027 0.000017 32 0.07671 0.07806 0.07940 0.08075 0.08210 0.08345 0.00027 0.000017 34 0.07638 0.07772 0.07907 0.08041 0.08175 0.08310 0.00027 0.000018 36 0.07605 0.07739 0.07873 0.08007 0.08141 0.08274 0.00027 0.000018 38 0.07573 0.07706 0.07840 0.07973 0.08106 0.08239 0.00027 0.000019 40 0.07541 0.07674 0.07806 0.07939 0.08072 0.08205 0.00027 o.ooooisf 42 0.07509 0.07641 0.07773 0.07905 0.08038 0.08170 0.00026 0.000020 44 0.07477 0.07609 0.07740 0.07872 0.08004 0.08135 0.00026 0.000020 46 0.07445 0.07576 0.07707 0.07838 0.07970 0.08101 0.00026 0.000021 48 0.07413 0.07544 0.07674 0.07805 0.07936 0.08066 0.00026 0.000021 50 0.07381 0.07512 0.07642 0.07772 0.07902 0.08032 0.00026 0.000022 52 0.07350 0.07479 0.07609 0.07739 0.07868 0.07998 0.00026 0.000023 54 0.07318 0.07447 0.07576 0.07706 0.07835 0.07964 0.00026 0.000023 56 0.07287 0.07415 0.07544 0.07673 0.07801 0.07930 0.00026 0.000024 58 0.07255 0.07383 0.07512 0.07640 0.07768 0.07896 0.00026 0.000025 60 0.07224 0.07352 0.07479 0.07607 0.07734 0.07862 0.00026 0.000026 62 0.07193 0.07320 0.07447 0.07574 0.07701 0.07828 0.00026 0.000027 64 0.07161 0.07288 0.07414 0.07541 0.07668 0.07794 0.00026 0.000028 66 0.07130 0.07256 0.07382 0.07508 0.07634 0.07760 0.00026 0.000029 68 0.07098 0.07224 0.07350 0.07475 0.07601 0.07727 0.00026 0.000030 70 0.07067 0.07192 0.07317 0.07442 0.07568 0.07693 0.00026 0.000031 72 0.07035 0.07160 0.07285 0.07410 0.07534 0.07659 0.00025 0.000032 74 0.07004 0.07128 0.07252 0.07377 0.07501 0.07625 0.00025 0.000033 76 0.06972 0.07096 0.07220 0.07343 0.07467 0.07591 0.00025 0.000034 78 0.06940 0.07064 0.07187 0.07310 0.07434 0.07557 0.00025 0.000036 80 0.06909 0.07032 0.07155 0.07277 0.07400 0.07523 0.00025 0.000037 82 0.06877 0.07000 0.07122 0.07244 0.07366 0.07489 0.00024 0.000039 84 0.06845 0.06967 0.07089 0.07211 0.07333 0.07454 0.00024 0.000040 86 0.06812 0.06934 0.07056 0.07177 0.07299 0.07420 0.00024 0.000042 88 0.06780 0.06901 0.07022 0.07143 0.07264 0.07385 0.00024 0.000043 90 0.06748 0.06868 0.06989 0.07109 0.07230 0.07351 0.00024 0.000045 92 0.06715 0.06835 0.06955 0.07075 0.07195 0.07316 0.00024 0.000047 94 0.06682 0.06801 0.06921 0.07041 0.07161 0.07280 0.00024 0.000049 96 0.06648 0.06768 0.06887 0.07006 0.07126 0.07245 0.00024 0.000051 98 0.06615 0.06734 0.06853 0.06972 0.07091 0.07209 0.00024 0.000053 100 0.06581 0.06700 0.06818 0.06937 0.07055 0.07174 0.00024 0.000055 Approximate average decrease in weight per 0.1 F rise in dry-bulb temperature equals. 0.000017 lb per cubic foot. 6 CHAPTER 1. AIR, WATER AND STEAM The specific heat of air is the number of Btu required to raise the tem perature of 1 lb of air 1 F. Distinction should always be made between the instantaneous specific heat at any existent temperature and the mean specific heat, which is the average specific heat through a given tempera ture range. The mean specific heat is the value required in most calcu lations. The specific heats at constant pressure, Cp, and the specific heats, Cv, at constant volume are different. The specific heat at constant pressure is commonly used and it varies, under a pressure of one atmos phere, from a minimum at 32 F from which it increases with either increase or decrease of temperature. The value of 0.24, as the mean specific heat at constant pressure, is sufficiently accurate for use at ordinary tem peratures. Values for instantaneous and mean specific heats are given in Table 3. The mean specific heat of water vapor at constant pressure is taken as 0.45 for all general engineering computations. Table 4 is intended to aid in determining the density of moist air, taking into account its temperature, pressure, and moisture content. Example 1. To show the use of Table 4: Given air at 83 F dry-bulb and 68 F wetbulb (or a depression of 15 deg) with a barometric pressure of 29.40 in. of mercury. What will be the weight of this air in pounds per cubic foot? Solution. From Table 4 the weight of saturated air at 82 F and 29.00 in. barometer is found to be 0.07000 lb per cubic foot. There is a decrease of 0.00017 lb per degree drybulb temperature above 82 F. There is an increase of 0.00024 lb for each 0.1 in. above 29.00 in. From the last column of Table 4 it is found that there is an increase of approxi mately 0.000039 lb per degree wet-bulb depression when the dry-bulb is 83 F. Tabu lating the items: 0.07000 = weight of saturated air at 82 F and 29.00 in. Hg. bar. -- 0.00017 = decrement for 1 deg dry-bulb, 1 X 0.00017. + 0.00096 = increment for 0.4 in. bar., 4 X 0.00024. + 0.00059 = increment for 15 deg wet-bulb depression, 15 X 0.000039. 0.07138 = weight in pounds per cubic foot of air at 83 F dry-bulb, 68 F wet-bulb, 29.40 in. bar. It is usual to assume that dry air, moist air, and the water vapor in the air follow the laws of perfect gases. This assumption while not absolutely true, especially with saturated vapor at temperatures much above 140 F, is sufficiently accurate for practical purposes and it greatly simplifies computations. Boyle's Law refers to the relation between the pressure and volume of a gas, and may be stated as follows: With temperature constant, the volume of a given weight of gas varies inversely as its absolute pressure. Hence, if Pi and Pi represent the initial and final absolute pressures, and Vi and Vi represent corresponding volumes of the same mass, say one pound of gas, then yV-ri = P=i, or Pi Vi = Pi F*, but since Pi Vi for any given c.ase is . "t Pi a definite constant quantity, it follows that the product of the absolute pressure and volume of a gas is a constant, or PV = C, when T is kept constant. Any change in the pressure and volume of a gas at constant temperature is called an isothermal change. Charles' Law refers to the relation among pressure, volume, and tem perature of a gas and may be stated as follows: The volume of a given 7 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 weight of gas varies directly as the absolute temperature at constant pressure, and the pressure varies directly as (he absolute temperature at constant volume. Hence, when heat is added at constant volume, Vc, the resulting equation is P5-t ir\ Tt, or, for the same temperature range at constant pres Ti VJ sure, Pc, the relation is Vt Tt TV In general, for any weight of gas, W, since volume is proportional to weight, the relation among P, V, and T is where PV = WRT (3) P = the absolute pressure of the gas, pounds per square foot. V = the volume of the weight W, cubic feet. W = the weight of the gas, pounds. R = a constant depending on the nature of the gas. The average value of R for air is 53.34. T = the absolute temperature, degrees Fahrenheit. This is the characteristic equation for a perfect gas, and while no gases are perfect in this sense, they conform so nearly that Equation 3 will apply to most engineering computations. HUMIDITY Humidity is the water vapor mixed with dry air in the atmosphere. Absolute humidity has a multiplicity of meanings, but usually the term refers to the weight of water vapor per unit volume of space occupied, expressed in grains or pounds per cubic foot. With this meaning, absolute humidity is nothing but the actual density of the water vapor in the mixture and might better be so called. A study of the Properties of Saturated Steam in Table 8 indicates that water vapor, either saturated or superheated, at partial pressures lower than 4 in. of mercury may be treated as a gas with a gas constant R of 1.21 (with partial pressure of vapor expressed in inches of Hg.) in the characteristic equation of the gas pV = wR (t + 460). Within such limits, the density (d) of water vapor is d = -y = i.2i ('/+ 460) (Punds Per cubic foot) W = (grains per cubic foot) ' (4a) where e = actual partial pressure of vapor, inches of mercury. t = dry-bulb temperature, degrees Fahrenheit. Specific Humidify It simplifies many problems which deal with mixtures of dry air and water vapor to express the weight or the mass of the vapor in terms of the weight or the mass of dry air. If the weight of the water vapor in a mixture be divided by the weight of the dry air, and the weight of dry air 8 CHAPTER 1. AIR, WATER AND StEAM be made unity, we have an expression of the weight of water vapor carried by a unit weight of dry air. This relation has no generally accepted name. It has been variously called: mixing ratio, proportionate humidity, mass or density ratio, absolute humidity, and specific humidity. Of all these terms specific humidity is' the most suggestive of the meaning which it is desired to express and it has found considerable use in this sense even though it is defined in International Critical Tables as the ratio of the piass of vapor to the total- mass. It will be understood here that specific humidity refers to the weight of water vapor carried by one pound of dry air. ., The gas constant for dry air, when the partial pressure of the air is expressed in inches of Hg., is 0.753; so that the specific humidity, if represented by W, is '. . W = -- - e____ - -- ____: Ihl______ . . 1.210 + 460) 0.753 (1 + 460) . = 0.622 (pounds) . . . . . (5) = 4354 (grains) where ' /. . ' t = actual partial pressure of vapor, inches of mercury. . .' B = total pressure of mixture (barometric pressure), inches of mercury. (5a) . - Relative Humidity ' - ---- . " ...... Relative humidity ($) is either the ratio of the actual partial pressure, e, of the water vapor in the air to the saturation pressure, et, atthe drybulb temperature, or the ratio of the actual density, d, of the vapor to the density of saturated vapor, dt, at the dry-bulb temperature. That is: The relative humidity of a given mixture at a'given temperature is not the same as the specific humidity, W., of the mixture divided by the specific humidity, Wt, of saturated vapor at the same temperature,, for from Equations 5 and 6 ; ; . . == 0.622 -- e(-) -s- 0.622 (---) = . (7) The specific humidity of an unsaturated air-vapor mixture cannot, therefore, be accurately found by multiplying the specific humidity of saturated air by its relative humidity; although the error is usually small especially when the relative humidity is high. : With a relative humidity of 100 per cent, the dry-bulb, wet-bulb, and dew-point temperatures are equal.. With a relative humidity less than 100 per cent, the dry-bulb exceeds the wet-bulb, and the wet-bulb exceeds the dew-point temperature. Example 2. Given air with a dry-bulb temperature of 80 F, relative humidity of 55 per cent, and a barometric pressure of 28.85 in. Hg., calculate the weight of a cubic foot of mixture, and the volume of 1 lb of the mixture. ., ... Solution. Pressure of saturated vapor at 80 F = et = 1.0316 in. Hg. (Table 6). i Pressure of the vapor in the mixture -- 1.0316 X 0.55 = 0.5676 in. Hg. 9 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Pressure of the dry air in the mixture = 28.85 -- 0.5676 = 28.282 in. Hg. pV -- wR (/ + 460) (R -- 0.753 when partial pressure of air is expressed in in. Hg.). 28.282 X 1 = da X 0.753 X (80 + 460). 28 282 da = o 753 x 540 = -06055 = we'f>ht of dry air in 1 cu ft of the mixture. Likewise from Equation 4, d ~l 21^x^540 = O'000^6^ lb = weight of vapor per cubic foot at 55 per cent relative humidity. Weight of 1 cu ft of the mixture = 0.06955 + 0.000868 = 0.070418 lb. Volume of 1 lb of the mixture = q 070418 = 14.2 cu ft. RELATION OF DEW-POINT TO RELATIVE HUMIDITY A peculiar relationship exists between the dew-point and the relative humidity and this is found most useful in air conditioning work. This relationship is, that for a fixed relative humidity there is substantially a constant difference between the dew-point and the dry-bulb temperature over a considerable temperature range. Table 5, giving the dry-bulb and dew-point temperatures and the dew-point differentials for 50 per cent relative humidity, illustrates this relationship clearly. Table 5. Temperatures for 50 Per Cent Relative Humidity Dry-bulb temperature.................. .... .... 65.0 Dew-point temperature. ..... 45.8 Difference between dew-point and drybulb temperature...................................... 19.2 70.0 50.5 19.5 75.0 80.0 85.0 90.0 55.25 59.75 64.25 68.75 19.75 20.25 20.75 21.25 It will be seen from an inspection of this table that the difference between the dew-point temperature and the room temperature is approxi mately 20 deg throughout this range of dry-bulb temperatures or, to be more exact, the differential increases only 10 per cent for a range of practically 25 deg. This principle holds true for other humidities and is due to the fact that the pressure of the water vapor practically doubles for every 20 deg through this range. The approximate relative humidity for any difference between dew point and dry-bulb temperature may be expressed in per cent as: . 100 where t = dry-bulb temperature, degrees Fahrenheit. h = dew-point temperature, degrees Fahrenheit. This principle is very useful in determining the available cooling effect obtainable with saturated air when a desired relative humidity is to be maintained in a room, even though there may be a wide variation in room 10 ' 1 .! | | j | I | | i 1 P I I CHAPTER 1. AIR, WATER AND STEAM temperature. This problem is one which applies to certain industrial con- ditions, such as those in cotton mills and tobacco factories, where re latively high humidities are carried and where one of the principal prob lems is to remove the heat generated by the machinery. It also permits the use of a differential thermostat, responsive to both the room tempera- ture and the dew-point temperature, to control the relative humidity in the room. Table 6 gives, for different temperatures, the density of saturated vapor, dt, the weight of saturated vapor mixed with 1 lb of dry air, Wt, (at a relative humidity of 100 per cent and a barometric pressure, B, of 29.92 in. of mercury), the specific volume of dry air, and the volume of an air-vapor mixture containing 1 lb of dry air (at a relative humidity of 100 per cent and a pressure of 29.92 in. of mercury). The preceding equations or the data from Table 6 may be conveniently used in solving the following typical problems: j Example 3. Humidifying and Heating. Air is to be maintained at 70 F with a relative. humidity of 40 per cent (<I> = 0.4) when the outside air is at 0 F and 70 per cent- relative humidity (4> = 0.7) and a barometric pressure, B, of 29.92 in- of mercury.Find; the weight of water vapor added to each pound of dry air and the dew-point temperature of the humidified air. ; Solution. From Equation 5 and Table 6, - W, = 0.622 ( 29^2X- 0 02M ) = 0 000548 lb Per Pund of dlT air- W, = 0.622 ( 29^92 -0 afiT ) = 0 00618 Ib Per pound of dry air. The water vapor added per pound of dry air must be (Wt -- Wi) or 0.005632 lb. By inspection of Table 6, IFt = 0.00618 at 44.5 F, so this is the dew-point temperature of the humidified air. : r- ' . An approximation of the same result from Table 6 is : Wi = 0.7 X 0.0007852 = 0.00054964 lb per pound of dry air. Wt -- 0.4 X 0.01574 = 0.006296 lb per, pound of dry air. " The water vapor added per pound of dry air is approximately 0.00574636 lb and the dew-point temperature is approximately 45 F. The degree of approximation is evident. Example 4- Dehumidifying and Cooling. Air with a dry-bulb temperature of 84 F, a wet-bulb of 70 F, or a relative humidity of 50 per cent (<f> = 0.5), and a barometric pressure, B, of 29.92 in. of mercury is to be cooled to 54 F. Find the dew-point tem perature of the entering air and the weight of vapor condensed per pound of dry ah'- Solution. From Equation 5 and Table 6, .. : Wt = 0.622 (29 92^-^5876) = 0 01248 lb P** pound of dry air. Wt = 0.622 ( 29 92 -o42003 ) = 0 00887 lb P" Pund of dry air. Since Wi = Wt when l -- 63.4 F, this is the dew-point temperature of the entering air. The weight of vapor condensed is (WT -- Wt) or 0.00361 Ib per pound of dry air. An approximate result is Wi 0.5 X 0.02543 = 0.012715 lb per pound of dry air. Wt = 1 X 0.008856 = 0.0088561b per pound of dry air, since the exit air is saturated. Since Wi = Wt at t = 64 F, this is the dew-point temperature of the entering air. The weight of vapor condensed is 0.003859 lb per pound of dry air. The degree of approxi- mation is again evident. 11 Pr o per ties op Sa tu r a te d W a te r V apor w it h A ir a t L ow T em peratures* (P ar t I ) HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 CHAPTER 1. AIR, WATER AND STEAM A | Po a$X jl 3 *o jg aT Q.0) 8)00 O AcoGoOo oNo CcOo oo ao co oo oo QOOOlCNONt-Rt't' tfWCQM -- oe*occocoorc^occoo t RCO}>CD CD CO r 1 I 1 1 1 Mill M M 1 II M 1 1 M M 1 1 1 II I I 1 1 | Compiled by W . M . Sawdon, vapor pressures converted from International Critical Tables. T a b le 6. Properties op Sa tu r a te d W ater V apor w it h A ir a t L ow T em peratures* (P ar t I, C o n tin u e d ) -tJf 3 a m .opm5 li > tS oI r d3 o B i.5 &6 Lb per Sq In. is |X o Pounds X10 *o e o 5 a <& of 1 lb of Dry Air of lib of 1 | Dry Air OP Datum Vapor 32 F Datum Dry Air with Vapor to Saturate it 7.047 7.638 8.316 9.017 9.806 10.84 11.53 12.51 13.63 14.69 15.87 17.20 18.58 20.10 21.72 23.47 25.34 27.29 29.52 31.81 34.37 37.01 39.96 43.04 46.33 49.87 83.69 67.66 61.81 66.41 71.17 76.64 82.28 88.19 94.62 3.4604 3.7507 4.0837 4.4281 4.8156 5.2264 5.6635 6.1449 6.6459 7.2167 7.7953 f 8.4486 9.1265 9.8731 10.669 11.517 12.436 13.394 14.489 15.614 16.883 18.179 19.628 21.141 22.757 24.496 26.323 28.318 30.361 32.621 34.959 . 37.646 40.416 43.319 46.477 0.016990 .017284 .018767 .020292 .022009 0.023817 .025738 .027851 .030041 .032530 0.035049 .037885 .040817 .044037 .047463 0.051151 .055082 .059165 .063831 .068605 0.073933 .079405 .085510 -.091865 .098632 0.10590 .11350 .12179 .13024 .13959 0.00112 .00121 .00131 .00142 .00154 0.00167 .00180 .00195 .00210 .00228 0.00245 .00265 .00286 .00308 .00332 0.00358 .00386 .00414 .00447 .00480 0.00518 .00556 .00599 .00643 .00690 0.00741 .00795 .00853 .00911 .00977 0.01044 .01122 .01201 .01285 .01375 0.1465 .1688 .1729 .1875 .2039 0.01026 .01112 1 .01210 .01312 .01427 9.19 9.21 9.23 9.26 9.29 .0.2212 0.01548 .2397 .01678 .2601 .01821 .2813 .01969 .3054 .02138 9.31 9.34 9.36 9.39 0.41 R* R* l tO . 00)900 0.3299 .3576 .3863 .4179 .4516 0.02309 .02503 .02704 .02925 1 .03161 1 0.4879 .5268 .5674 .6137 .6613 . 0.03415 .03688 .03972 .04296 .04629 9.56 ` 9/59 9.61 9' .64 9.66 h-r-t-r03 03 003 03 0.7146 .7694 .8308 .8948 .9632 0.05002 .05386 .05816 .06264 .06742 1.037 1.114 1.199 1.285 1.381 0.07259 .07798 .08393 .08995 .09667 9.82 9.84 9.87 9.89 9.92 1.480 1.593 1.711 1.833 1.967 0.10360 .11151 .11977 .12831 .13789 * 9.94 9.97 9.99 10.02 10.04 caoco'foooo^oco oNoNoNoHHo 11111 Cto 03 --CO CRPf CCOO 03 01003 0 9.19 9.21 9.23 9.26 9.29 | . 9.31 9.34 9.36 9.39 9.41 9.44 9.46 9.49 9.51 9.54 0)03 03030 9.69 9.72 9.74 9.77 9.79 ! i 9.94 9.97 9;99 . 10.02 10.04 . -23.04 -22.79 -22.55 -22.30 -22.05 -21.81 -21.56 -21.32 -21.07 -20.83 -19.36 -19.11 -18.87 -18.62 -18.38 -18.13 -17.89 -17.64 -17.40 -17.16 -16.91 -16.67 -16.42 -16.18 -15.94 -15.69 -15.45 -15.21 -14.96 -14.72 1016.5 1016.9 1017.4 1017.8 1018.3 1018.7 1019.2 1019.6 1020.1 1020.5 1021.0 1021.4 1021.9 1022.3 1022.8 1023.2 1023.7 1024.1 1024.6 1025.0 1025.5 1025.9 1026.4 1026.8 1027.3 1027.7 1028.2 1 , 1028.6 1029.1 1029.5 1030.0 1030.4 1030.9 1031.3 1031.8 -23.04 -22.79 -22.65 -22.30 -22.06 -21.81 -21.66 -21.32 -21.07 -20.83 -20.58 -20.34 -20.09 -19.84 1 -19.60 -19.36 -19.10 -18.86 i --1188..631/ -18.12 -17.88 , -17.63 -17.39 -17.15 -16.90 -18.66 -16.41 ! -16.17 -15.93 r-pjoss* M1M RO*MtcQoOa)' `Compiled by W . M . Sawdon, vapor pressures converted' from International Critical Tables. 13 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 14 15 T a b le 6. Pro perties op Sa tu r a te d W ater V apor w it h A ir a t L ow T em peratures8 (P ar t I , C o n tin u e d ) aCompiled by W . M . Sawdon, vapor pressures converted from International Critical Tables. CHAPTER 1. AIR, WATER AND STEAM HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 16 17 I I )T a b l e 6. P r o p e r t ie s o f Sa t u r a t e d W a t e r V a p o r w it h A ir , 0 F to 200 F a (P a r t Compiled by W. M . Sawdon, vapor pressures converted from International Critical Tables. T a b l e 6. Pr o p e r tie s of Sa t u r a t e d W a te r V apor w it h A ir , 0 F to 200 F a (P a r t I I , C o n t in u e d ) :Compiled by W..M. Sawdon, vapor preuuree converted from International Critical- fabler ' CHAPTER 1. AIR, WATER AND STEAM T able 6. Properties of Saturated Water Vapor with A ir, 0 F to 200 Fa (Part I I , Continued) `Compiled by W . M . Sawdon, vapor pressures converted from International Critical Tables. T able 0. Properties of Saturated Water Vapor with A ir , 0 F to 200 Fa (Part I I , Continued) Compiled by W. M ; Sawdon. vapor pressures converted from International Critical Tables, HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 18 CHAPTER 1. AIR, WATER AND STEAM ES . oo oooo oo oo oe4 0-eoco 3 CO CO Is. C4 -< 3 C3 COOO 04tW0 C5 3 COCO |s.OI<-4 O3coao <00533 >cocos t.000005 oc)0<hh ^J 04 3 i-"< 300HeO O0 O CO CO 04 ts. ON VSO 3 00 r-> CO H co3d sNcoao ohnw^ <> bo SonVin 3 r-. oo c SnmSS &S OtM > cd Z 22222 22222 22222 222 oo oooo oooo IS 04 04 04 CO CO CO COCO 3 3 3 t- t-ts-00 C5 00 00 05 C5 ffl 050000 33333 3 33 3 3 3 3 33 3 3 33 3 3 33333 3 oooo05co S32C?2 22:X2 CO CO CO CO 3 co 3 3 o S2S2S2 S52222 3 3333 3 eo oo co'onsojoo coo-^co-oh .33 3 w* 3 eo 350*0404* 0000043 os oo oi eo 00 .-1 oooo* onnn o--ooo 3 04*05 nonion ts 00 CO 00 CO eo 3 3 ts.ts.'rsioo'-i ocoooeo cjocj ct o NP0O0J04OO0COO00H^0HOr- 0^0OtoN00O5N00NC50'0Ot5N0O0 0CHCCO5CO0--S4-^0Ct(H-OD-02SOO5-0Oto-b Cc5O 030C-O.o04>1t0. ocoomh ggggg Iss00 4 r-eoooot-- t*. a> 04 p. co 300wN C5CO 0004 tWP>M^HC4C4 04C0C033 10 0 OM3 lO OOHIO0H4 cOo ps.ls.tDcO CO 04 co 3 CO CO CO CO CO 8S88S 04 CJ C5 *-l 0404wH<-( p- co. 0- O0 05 O -! 005000MC000003003 0.00 040 HHOJNMHHIQ5 I 3 04 .-1 CO 05S00. 0000CO 0-0 00000 00000. fJHOO C3O!*^?CO?O^- ' 0C0OcCO`"`S"" 3 P- 04 CO 0w40CO3CtO-C045 N-- S--N---S---S- 05 00 0 & 8 IS. 0*0. ntCQC4 HhhSc* 3 00505 o.04 COCO 0---0---4---- _ . o-^3 3 >4 05 00 00 05 .-.CO eo 00 co co 3053 ts.ts.Q0Q0 OOOp'H -'.*05 05 04 04 3 04 00 3 o ts. mos'pH 04 04 05 3 3 >--m 04 04 04 04 04 04*04*04 04*04 04*04 04* o. 3 3C0 0504 3 s-pl 001f--.TSp- .-i 0405053 CO9O5OO33Or00O00O440005 ftO0H>Ojt3? 55O304C POO04CS 35353fiN33 C5CD t2- CoO4O3 043PS.004 CSD rnt> sp rS*5 Xsl d 04 04 04 04 04 04 04 O4OT04 C4 CO CO COCO 05 05 05 0505 05 3 3 3 3 3333 '''* t 19 Water Vapor w ith A ir , 0 F to 200 F * (Part I I , Continued) rr HEATING VENTILATING AIR CONDITIONING GUIDE 1940 20 T a b l e 6. P r o p e r t ie s o f Sa t u r a t e d W a t e r V a p o r w it h A ir , 0 F to 200 Fa (P a r t I I , CHAPTER 1. AIR, WATER AND STEAM Dry Air with Vapor to S iatturate 22828 32383 8S38S SS8828 S8883 3 siigg mm iiisi ini mu i 3 Vapor 32 F Datum 1 ovoeooo Nfo ioowooco o^roswoo m 5 SS|S'S2332_S3333 233S2' SSS23 I 6 D ry Air OF Datum 38S88 SSPSS 38823 88S83 82888 B 58333 33333 33333 33333 33333 3 of 1 lb of D ry A ir + Vapor to Saturate it & 38E32 SKS3BS8B33 8S283 SS83S 88838 88383 B8S33 38888 SSSSK 8 f 1 tf >is 838SS 3222s aaass sssss sssss s 22222 22222 22222 22222 22222 2 | . c fllb o f D ry Air [ per lb o f D ry A ir Pounds oeoo>coo - H^HA OOOOO OOOOO o 1 iiiil lilli Hill IfIII ggggg g 1 ea Hill lilli iiiil mm ishii O O-- c JcO3a W^COOCO NHHP4N eouor-oeo SMSWO ho c> s Eoa* - BSsss 33333 33322 Iiiil | , per Cu F t 1 1 O 0-0 o o o j In. o f Hg. Lb per 8q In. mm mm0s Silas, -Hhs. W t-t-t- r*ttaoao ooooaooo oqoqo ooohh ** ii 1 S3SS3.8833$<33318 SSSSS 2IISi 3 22SS3 22222 35522 22288 SS888 8 IV . SS5S8 88332 33333'33332 assgs 1 21 022045 022497 022956 023424 023900 029700 by W. M. Sawdon, vapor pressures converted from International Critical Tables. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Since Table 6 was prepared, the new steam tables, Thermodynamic Properties of Steam, by J. H. Keenan and F. G. Keyes, have been pub lished. For the last two years an A.S.H.V.E. Research Technical Advisory Committee on Psychrometry has been formulating standard psychrometric data, on a tentative basis. Included in this Committee's work is a revision of Table 6 to bring it into conformity with the Keenan and Keyes tables. Pending acceptance by the Society of the Committee's. report, the tabular data and psychrometric chart published in earlier editions of The Guide have been retained. ADIABATIC SATURATION OF AIR The process of adiabatic saturation, or evaporative cooling, is of con siderable importance in air conditioning. Suppose that unsaturated air be made to pass at a steady rate through a tunnel which is perfectly insulated against heat transfer to or from its surroundings, and which contains an exposed water surface. Alternatively, let the air pass through an insulated air washer whose spray water is recirculated continuously without being heated or cooled externally. In either case, when the apparatus has reached equilibrium temperatures throughout, the water will have at tained a temperature (the temperature of adiabatic saturation) closely approximating the initial wet-bulb temperature of the air, and the air will have become saturated at the temperature of the water (or will have approached saturation at that temperature as a limit, the degree of saturation depending on the time and efficiency of contact of air and water). '' Example 5. If air with a dry-bulb of 85 F and a wet-bulb of 70 F be saturated adia- batically by spraying with recirculated water, what will be the final temperature and the vapor content of the air? Solution. The final temperature will be equal to the initial wet-bulb temperature or 70 F, and since the air is saturated at this temperature, from Table 6, W = 0.01574 lb per pound of dry air. The energy for evaporating moisture into the air comes only from the air and its initially superheated vapor, which led Carrier to formulate the following energy equation for adiabatic saturation: A'fe (WVW) = Cpa (I - /') + cPsW (f - t<) (9) and using cPa = 0.24 and ePa = 0.45 A'fg (JFf - W) = (0.24 + 0.45HO {t - t') (9a) where h'fg = latent heat of vaporization at t\ Btu per pound. . (Wt> -- W) -- increase in vapor associated with 1 lb of dry air when it is saturated adiabatically from an initial dry-bulb temperature, t, and an initial vapor content, W, pounds. : Knowing any two of. the three primary variables, t, t`, or W, the third may be found from this equation for any process of adiabatic saturation. TOTAL HEAT AND ENTHALPY The total heat of a mixture of dry air and water vapor was originally defined by W. H. Carrier as: ; 22. CHAPTER 1. AIR, WATER AND STEAM 2 = Cpa (1 - 0) + W [A',g + Cps -- I')l dO) where 2 = total heat of the mixture, Btu per pound of dry air. Cpa = mean specific heat at constant pressure of dry air. . . tps = mean specific heat at constant pressure of water vapor. t = dry-bulb temperature, degrees Fahrenheit., t' = wet-bulb temperature, degrees Fahrenheit. W 1 weight of water vapor mixed with each pound of dry air, pounds. A'fg = latent heat of vaporization at Btu per pound. Since this definition holds for any mixture of dry air and water vapor, the total heat of a mixture with a relative humidity of 100 per cent and at a temperature equal to the wet-bulb temperature (/') is: S' = pa O' - 0) + Wv h'fg (11) By equating Equation 10 to Equation 11, the equation for the adiabatic saturation process, Equation 9a, follows. This demonstrates that the adiabatic saturation process at approximately constant wet-bulb tempera ture is also approximately a process of constant total heat. In short, the total heat of a mixture of dry air and water vapor is the same for any two states of the mixture at the same wet-bulb temperature. This fact furnishes a convenient means of finding the total heat of an air-vapor ' mixture in any state. Enthalpy This total heat of an air-vapor mixture is not equal to the enthalpy of the mixture, since the enthalpy of the liquid is not included in,Equation 10. With the meaning of enthalpy in agreement with present practice in other branches of thermodynamics, the true enthalpy of a mixture of dry air and water vapor (with 0 F as the datum for dry air, and the saturated liquid at 32 F as the datum for the water vapor) is: h = Cpa (J - 0) + W hs = 0.24 (t - 0) + W.h8 (12) where ' h = the enthalpy of the mixture, Btu per pound of dry air. t -- the dry-bulb temperature, degrees Fahrenheit. W = the weight of vapor per pound of dry air, pounds. h, = the enthalpy of the vapor in the mixture, Btu per pound. . The enthalpy of the water vapor in the mixture may be found in steam, charts or tables when the dry-bulb temperature and the partial pressure of the vapor are known. Or, since the enthalpy of steam at low partial pressures, whether superheated or saturated, depends only upon tempera ture, the following empirical equation may be used: fta = 1059.2 + 0.45 t (13) Substituting this value of As in Equation 12, the enthalpy of the mixture is: h = 0.24 (I -- 0) + W (1059.2 -f 0.451) (14) HEATING VENTILATING AIR CONDITIONING. GUIDE 1940 ( The results obtained w$th> Equations U3Cand- 1$ agree well with values given in Table 6. They are not in such close agreement with values given by Keenan and Keyes in Table 8. ' Example 6. Find the enthalpy of an air-vapor mixture having a dry-bulb temperature of 85 F and a wet-bulb temperature of 70 Fand a' barometric pressure of 29.0 in.:Hg. Solution. From Equation 2a and,Table 6,; ... r_ * _ 07387 (29-0 - 0.7387) (85 - 70) : 2800--(1.3.X 70): : V ?51^ . From Equation 5, W = 0.622 0.5822 29.0 - 0.5822 0.01274. From Equation 14, h,= (0.24 X 85) + [0.01274 (1059.2 + 0.45 X 85)1 = 34.38 Btu per pound dry air. Since the enthalpy is nearly constant along a wet-bulb temperature line, in* any air-water vapor mixture, it may be>-found, approximately, Wyib.-Water Vapor MB. Dry Air ' Fig. 1. Diagram Illustrating Energy Equation 15 when the wet-bulb temperature is known by using-the temperature in Table 6 as wet-bulb temperatures and reading the corresponding enthalpy from the last column, provided the barometric pressure is 29.92 in. Hg, ENERGY EQUATION An energy equation can be written, that applies, in general, to various air conditioning processes, and this equation can be used to determine the quantity of heat transferred during such processes. In the most general form, this equation may be explained with the aid of Fig.T as follows: The rectangle may represent any apparatus, e.g., a drier, humidifier, dehumidifier, cooling tower, or the like, by proper choice of the direction of the arrows. ' In general, a mixture of air and water vapor; such as atmospheric air, enters the apparatus at 1 and leaves at 3. Water is supplied at some temperature, t>. For the flow of 1 lb of dry air (with accompanying vapor) through the apparatus, provided there is no appreciable change in the elevation1 or velocity of the fluids and no mechanical energy delivered to or by the apparatus, A, + Eh + (Wt --" Wi) ft, = A, + Ec or Eh - Ec = h, - ft, - (IF, - IF,) ft. 24 (15) ' .'.CHAPTER 1. AIR, WATER AND STEAM where ' . Eh =5 the quantity of heat supplied per pound of dry air, Btu. . . ., - Rz = the quantity of beat lost externally by heat transfer from, the . apparatus, / ' Btii per pound of dry air: `' ... - / IF; = the .weight of Water vapor entering, per pound of dry air. ' ", 1 . Wi *= the weight of water vapor leaving, per pound of.dry air. _ ft, the enthalpy of the water supplied at U, Btu per pound. ............." ` ' ft, -- *i = the increase in the enthalpy of the air-water vapor mixture in passing through the apparatus, Btu per pound of dry air . = 0.24 (I, - I.) + W, (1059.2 + 0.45 /,) - IF, (1059.2 + 0:451,) .. The net quantity of heat added to or removed from air-water vapor, mixtures in . air conditioning work is frequently approximated by taking the differences iri'total heat at exit and entrance. ' . . . .'. For example,. inFig. 1, an approximate result is: , . ;'. Eh - Ec = S, - S, . (16) From the definitions of total heat and enthalpy, it may be demon strated that Equation 16 is exactly equivalent to Equation 15, when, and only when, t's = t\ = k; i.e., when the initial and final wet-bulb tempera tures and the temperature of the water supplied are equal. The one pro cess that meets these conditions is adiabatic saturation, and for this process either equation will give a result of zero. For other conditions, Equation 16 is approximate but satisfactory for many calculations. The following problems illustrate the application of these;principles: Example 7. Heating (data from Example 3). Assuming the water to be supplied at 50 F, the net quantity of heat supplied is, from Equation 15, From Equation 15, . : . h - Ec = ft, - A, - (IF, - IF,) (50 - 32) ` A, '= (0.24 X 70) + [0.00618 (1059.2 + 0.45 X 70)] = 23.54 ; Btu per pound leaving dry air : . A, = (0.24 X 0) + [0.000548 (1059.2 ;+ 0.45 X 0)] = 0.58 : ' Btu: per pound entering dry air : : - Eh - Ec = 23.54 - 0.58 - [0.005632 (50 -- ;32)] = 22.86 Btu per ' ; ' pound dry air, net heat supplied ; : Example 8. Cooling (data from Example 4). If the condensate is removed at 54 F the quantity of heat removed is found from liquation 15, by proper regard to the arrow direction in Fig. 1, ' ` From Equation 15, . Eh -I- Ec - ft, - ft, - (IF, - JF.) (54 - 32) . - A, = (0.24 X 84) + [0.01248 (1059.2 + 0.45 X 84)] = 33.85 . ( Btu! per pound entering dry air !' ft, = (0.24 X 54) + [0.00887 (1059.2 + 0.45 X 54)] = 22.57 1 : . Btu per pound leaving dry air .. Eh + Ec = 33.85 - 22.57 - [0.00361 (54 - 32)] = 11.20 Btu per pound dry air, net heat removed Using Table 6, the initial enthalpy of' the air-vapor mixture, since the wet-bulb temperature is 70 F, is 33.96 Btu per pound of dry air. ' The final enthalpy is, from Table 6, since the exit air is saturated, 22.55- Btu per pound. Hence, using Equation 16, the quantity of heat removed is, approximately, (33.96 -- 22.55) or 11.41. Btu per pound of dry air. The degree of approximation to the correct result is evident in this example. ' : . . . ,. , . 25 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 PSYCHROMETRIC CHART Many types of charts which give graphical solutions of the psychro- metric equations, and other useful data, have been devised. One of these, the Revised Bulkeley Psychrometric Chart6, will be found attached to the inside back cover of this book. Detailed instructions in the use of this chart will be found thereon. . PROPERTIES OF WATER Composition of Water. Water is a chemical compound (HjO) formed by the union of two volumes of hydrogen and one volume of oxygen, or two parts by weight of hydrogen and 16 parts by weight of oxygen. Density of Water. Water has its greatest density at 39.2 F, and it expands when heated or cooled from this temperature. At 62 F a U. S. gallon of 231 cu in. of water weighs approximately lb, and a cubic foot of water is equal to 7.48 gal. The specific volume of water depends on the temperature and it is always the reciprocal of its density. (See Table 7.) Table 7. Thermal Properties of Water- Temperature Deg F 32 40 SO 60 70 80 90 100 . 110 120 130 140 ISO 160 170 180 190 200 210 212 220 240 260 280 300 3S0 400 4S0 500 5S0 600 700 Sat. Press. Lb per Sq In. 0.0887 0.1217 0.1780 0.2561 0.3628 0.5067 0.6980 0.9487 1.274 1.692 2.221 2.887 3.716 4.739 5.990 7.510 9.336 11.525 14.123 14.696 17.188 24.97 35.43 . 49.20 67.01 134.62 247.25 422.61 681.09 1045.4 1544.6 3096.4 Volume Cu Ft per Lb 0.01602 0.01602 0.01602 0.01603 0.01605 0.01607 0.01610 0.01613 0.01616 0.01620 0.01625 0.01629 0.01634 0.01639 0.01645 0.01650 0.01656 0.01663 0.01669 0.01670 0.01676 0.01690 0.01706 0.01723 0.01742 0.01797 0.01865 0.01950 0.02050 0.02190 0.02410 0.03940 Weight Lb per Cu Ft 62.42 62.42 62.42 62.38 62.31 62.23 62.11 62.00 61.88 . 61.73 61.54 61.39 61.20 61.01 60.79 60.61 60.39 60.13 59.92 59.88 59.66 59.17 58.62 58.04 57.41 55.65 53.62 51.30 48.80 45.70 41.50 25.40 ' ' Specific Heat 1.0093 1.0048 1.0015 0.9995 0.9982 0.9975 0.9971 0.9970 0.9971 0.9974 0.9978 0.9984 0.9990 0.9998 1.0007 1.0017 , 1.0028 1.0039 1.0052 1.0055 1:0068 1.0104 1.0148 1.0200 1.0260 1.0440 1.0670 1.0950 1.1300 1.2000 1.3620 -- The original Bulkeley Psychrometric Chart was presented to the Society in 1926. (See A.S.H.V.E. Transactions. Vol. 32, 1926, p. 163). Single copy of the revised chart can be furnished at a cost of 6 .25. - 26 CHAPTER 1. AIR, WATER AND STEAM Table 8. Properties of Saturated Steam: Pressure Table3 Abs. Press. In. He. .P Temp F t Specific Volume Sat. Liquid Vf Sat. Vapor . V, Enthalpy Entropy Sat. Liquid hf Evap. hfg Sat. Sat. Vapor Liquid h. Sf Evap. Sfg Sat. Vapor Sg 0.25 0.50 0.75 1.00 1.5 40.23 58.80 70.43 79.03 91.72 0.01602 0.01604 0.01606 0.01608 0.01611 2423.7 1256.4 856.1 652.3 444.9 8.28 26.86 38.47 47.05 59.71 1071.1 1060.6 1054.0 1049.2 1042.0 1079.4 1087.5 1092.5 1096.3 1101.7 0.0166 0.0532 0.0754 0.0914 0.1147 2.1423 2.0453 1.9881 1.9473 1.8894 2.1589 2.0986 2.0635 2.0387 2.0041 2 101.14 0.01614 339.2 69.10 1036.6 1105.7 0.1316 1.8481 1.9797 4 125.43 0.01622 176.7 93.34 1022.7 1116.0 0.1738 .1.7476 1-9214 6 140.78 0.01630 120.72 108.67 1013.6 1122.3 0.1996 1.6881 1.8877 8 152.24 0.01635 92.16 120.13 1006.9 1127.0 0.2186 1.6454 1.8640 10 161.49 0.01640 74.76 129.38 1001.4 1130.8 0.2335 1.6121 1.8456 12 169.28 0.01644 14 176.05 0.01648 16 182.05 0.01652 18 187.45 0.01655 20 192.37 0.01658 63.03 54.55 48.14 43.11 39.07 137.18 143.96 149.98 155.39 160.33 996.7 992.6 988.9 985.7 982.7 1133.9 1136.6 1138.9 1141.1 1143.0 0.2460 0.2568 0.2662 0.2746 0.2822 1.5847 1.5613 1.5410 1.5231 1.5069 1.8307 1.8181 1.8072 1.7977 1.7891 22 24 26 28 30 Lb Sq In. 14.696 16 18 20 22 24 26 28 196.90 201.09 205.00 208.67 212.13 212.00 216.32 222.41 227.96 233.07 237.82 242.25 246.41 0.01661 0.01664 0.01667 0.01669 0.01672 0.01672 0.01674 0.01679 0.01683 0.01687 0.01691 0.01694 0.01698 35.73 32.94 30.56 28.52 26.74. 1G4.S7 169.09 173.02 176.72 180.19 979.8 977.2 974.8 972.5 970.3 1144.7 1146.3 1147.8 1149.2 1150.5 0.2891 0.2955 0.3014 0.3069 0.3122 1.4923 1.4789 1.4665 1.4550 1.4442 1.7814 1.7744 1.7679 1.7619 1.7564 26.80 24.75 22.17 20.089 18.375 16.938 15.715 14.663 180.07 184.42 190.56 196.16 201.33 206.14 210.62 214.83 970.3. 1150.4 967.6 1152.0 963.6 1154.2 960.1. 1156.3 956.8 1158.1 953.7 1159.8 950.7 1161.3 947.9 1162.7 0.3120 0.3184 0.3275 0.3356 0.3431 0.3500 0.3564 0.3G23 1.4446 1.4313 1.4128 1.3962 1.3811 1.3672 1.3544 1.3425 1.7566 1.7497 1.7403 1.7319 1.7242 1.7172 1.7108 1.7048 30 250.33 0.01701 . 13.746 218.82 945.3: 1164.1 0.3680 1.3313 1.6993 32 254.05 0.01704 12.940 222.59 942.8 1165.4 0.3733 1.3209 1.6941 34 257.58 0.01707 12.226 226.18 940.3 1166.5 0.3783 1.3110 1.6893 36 260.95 0.01709 11.588 229.60 938.0 1167.6 0.3831 1.3017 1.6848 38 264.16 0.01712 11,015 232.89 935.8 1168.7 0.3876 1.2929 1.6805 40 267.25 0.01715 42 270.21 0.01717 44 273.05 .0.0172046 275.80 0.01722 48 278.45 0.01725 10.498 10.029 9.601 9.209 8.848 236.03 239.04 241.95 244.75 247.47 933.7 931.6 929.6 927.7. 925.8 1169.7 1170.7 1171.6 1172.4 1173.3 0.3919 0.3960 0.4000 0.4038 0.4075 1.2844 1.2764 1.2687 1.2013 1.2542 1.6763 1.6724 1.6687 1.6652 1.6617 50 281.01 0.01727 52 283.49 0.01729 54 285.90 0.01731 56 288.23 0.01733 58 290.50 0.01736 8.515 8.208 7.922 7.656 7.407 250.09 252.63 255.09 257.50 259.82 924.0 922.2 920.5 918.8 917.1 1174.1 1174.8 1175.6 1176.3 1176.9 0.4110 0.4144 0.4177 0.4209 0.4240 1.2474 1.2409 1.2346 1.2285 L2226 1.65S5 1.6553 1.6523 1.6494 1.6466 60 292.71 0.01738 7.175 262.09. 915.5 1177.6 0.4270 1.2168 1.0438 62 294.85 0.01740 6.957 264.30 913.9 1178.2 0.4300 1.2112 1.6412 64 296.94 0.01742 6.752 266.45 912.3 1178.8 0.4328 1.2059 1.6387 66 298.99 0.01744 6.560 268.55 910.8 ,1179.4 0.4356 1.2006 1.6362 68 300.98 0.01746 . 6.378 270.60 909.4 1180.0 0.4383 1.1955 1.6338 70 302.92 0.01748 72 304.83 0.01750 74 306.68 0.01752 76 308.50 0.01754 78 310.29 0.01755 6.206 6.044 5.890 5.743 5.604 272.61 274.57 276.49 278.37 280.21 907.9 906.5 905.1 903.7 902.4 1180.6 1181.1 1181.6 1182.1 1182.6 0.4409 0.4435 0.4460 0.4484 0.4508 1.1906 1.1857 1.1810 1.1764 1.1720 1.6315 1.6292 1.6270 1.6248 1.6228 80 312.03 0.01757 82 313.74 0.01759 84 315.42 0.01761 86 317.07 0.01762 88 318.68 0.01764 5.472 5.346 5.226 5.111 5.001 282.02 283.79 285.53 287.24 288.91 901.1 899.7 898.5 897.2 895.9 1183.1 1183.5 1184.0 1184.4 1184.8 0.4531 0.4554 0.4576 0.4598 0.4620 1.1676 1.1633 1.1592 1.1551 1.1510 1.6207 1.6187 1.6168 1.6149 1.6130 90 320.27 0.01766 . 4.S96 290.56 894.7 1185.3 0.4641 1.1471 1.6112 92 321.83 0.01768 4.796 292.18 893.5 1185.7 0.4661 1.1433 1.6094 94 323.36 0.01769 4.699 293.78 892.3 1186.1 0.4682 1.1394 1.6076 96- 324.87 0.01771 4.606 295.34 891.1 -1186.4 0.4702 1.1358 1.6060 98 326.35 0.01772 4.517 296-89 889.9 1186.8 0.4721 1.1322 1.6043 Press. In. He. P 0.25 0.50 0.75 1.00 1.5 2.0 4.0 6 8 10 12 14 16 18 20 22 24 26 28 30 Lb Sq In. 14.696 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 Reprinted by permission from Thermodynamic Properties o Steam, by J. H. Keenan and F. G. Keyes, published by John Wiley and Sons. Inc. 27  HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 8. Properties of Saturated Steam: Pressure Table (Continued) Abs. Press. Lb Sq In. P Temp F t too 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 132 134 136 138 140 142 144 146 148 150 152 154 156 158 160 162 164 166 168 170 172 174 176 178 180 182 184 186 188 190 192 194 196 198 200 205 210 215 220 225 230 235 240 245 327.81 329.25 330.66 332.05 333.42 334.77 336.11 337.42 338.72 339.99 341.25 342.50 343.72 344.94 346.13 347.32 348.48 349.64 350.78 351.91 353.02 354.12 355.21 356.29 357.36 358.42 359.46 360.49 361.52 362.52 363.53 364.53 365.51 366.48 367.45 368.41 369.35 370.29 371.22 372.14 373.06 373.96 374.86 375.75 376.64 377.51 378.38 379.24 380.10 380.95 381.79 383.86 385.90 387.89 389.86 391.79 393.68 395.54 397.37 399.18 Specific Volume Enthalpy Entropy Sat. Liquid vr 0.01774 0.01775 0.01777 0.01778 0.01780 0.01782 0.01783 0.01784 0.01786 0.01787 0.01789 0.01791 0.01792 0.01793 0.01794 0.01796 0.01797 0.01799 0.01800 0.01801 0.01802 0.01804 0.01805 0.01806 0.01608 0.01809 0.01810 0.01812 0.01813 0.01814 0.01815 0.01817 0.01818 0.01819 0.01820 0.01822 0.01823 0.01824 0.01825 0.01826 0.01827 0.01829 0.01830 0.01831 0.01832 0.01833 0.01834 0.01835 0.01836 0.01838 0.01839 0.01842 0.01844 0.01847 0.01850 0.01852 0.01854 0.01857 0.01860 0.01863 Sat. Vapor V, Sat. Liquid hf Evap. hr* Sat. Sat. Vapor Liquid h* Sf Evap. Sfg Sat. Vapor S, 4.432 4.350 4.271 4.194 . 4.120 298.40 888.8 299.90 887.6 301.37 886.5 302.82 885.4 304.26 884.3 1187.2 1187.5 1187.9 1188.2 1188.6 0.4740 0.4759 0.4778 0.4796 0.4814 1.1286 1.1251 1.1216 1.1182 1.1149 1.6026 1.6010 1.5994 1.5978 1.5963 4.049 3.981 3.914 3.850 3.788 . 305.66 307.06 308.43 309.79 311.12 883.2 882.1 881.1 880.0 879.0 1188.9 1189.2 1189.5 1189.8 1190.1 0.4832 0.4849 0.4866 0.4883 0.4900 1.1117 1.1085 1.1053 1.1022 1.0992 1.5948 1.5934 1.5919 1.5905 1.5891 3.728 3.670 3.614 3.560 3.507 312.44 877.9 313.75 . 876.9 315.04 875.9 316.31 874.9 317.57 873.9 1190.4 1190.7 1190.9 1191.2 1191.5 0.4916 0.4932 0.4948 0.4964 0.4980 1.0962 1.0933 1.0903 1.0874 1.0845 1.5878 1.5865 1.5851 1.5838 1.5825 3.455 3.405 3.357 3.310 3.264 318.81 320.04 321.25 322.45 323.64 872.9 872.0 871.0 870.1 869.1 1191.7 1192.0 1192.2 1192.5 1192.7 0.4995 0.5010 0.5025 0.5040 0.5054 1.0817 1.0790 1.0762 1.0735 1.0709 1.5812 1.5800 1.5787 1.5775 1.6763 3.220 3.177 3.134 3.094 3.054 324.82 868.2 325.98 867.2 327.13 866.3 328.27 865.3 329.39 864.5 1193.0 1193.2 1193.4 1193.6 1193.9 0.5069 0.5083 0.5097 0.5111 0.5124 1.0682 1.0657 1.0631 1.0605 1.0580 1.5751 1.5740 1.5728 1.5716 1.5705 3.015 2.977 2.940 2.904 2.869 330.51 331.61 332.70 333.79 ,334.86 863.6 862.7 861.8 860.9 860.0 1194.1 1194.3 1194.5 1194.7 1194.9 0.5138 0.5151 0.5165 0.5178 0.5191 0.0556 1.0532 1.0507 1.0483 1.0459 1.5694 1.5683 1.5672 1.5661 1.5650 2.834 2.801 2.768 2;736 2.705 335.93 336.98 338.02 339.05 340.07 859.2 858.3 857.5 856.6 855.7 1195.1 1195.3 1195.5 1195.7 1195.8 0.5204 0.5216 0.5229 0.5241 0.5254 1.0436 1.0414 1.0391 1.0369 1.0346 1.5640 1.5630 1.5620 1.5610 1.5600 2.675 2.645 2.616 2.587 2.559 341.09 342.10 343.10 344.09 345.06 854.9 854.1 853.3 852.4 851.6 1196.0 0.5266 1196.2 0.5278 1196.4 0.5290 1196.5' 0.5302 1196.7 0.5313 1.0324 1.0302 1.0280 1.0259 1.0238 1.5590 1.5580 1.5570 1.5561 1.5551 2.532 2.505 2.479 2.454 2.429 346.03 347.00 347.96 348.92 349.86 850.8 850.0 849.2848.4 847.6 1196.9 1197.0 1197.2 1197.3 1197.5 0.5325 0.5336 0.5348 0.5359 0.5370 1.0217 1.0196 1.0175 1.0155 1.0136 1.5542 1.5532 1.5523 1.5514 1.5506 2.404 2.380 2.356 2.333 2.310 350.79 351.72 352.64 353.55 354.46 846-8 846.1 845.3 844.5 843.7 1197.6 1197.8 1197.9 1198.1 1198.2 0.5381 0.5392 0.5403 0.5414 0.5425 1.0116 1.0096 1.0076 1.0056 1.0037 1.5497 1.5488 2.5479 1.5470 1.5462 2.288 2.234 2.183 2.134 2.087 355.36 357.58 359.77 361.91 364.02 843.0 841.1 839.2 837.4 835.6 1198.4 1198.7 1199.0 1199.3 1199.6 0.5435 0.5461 0.5487 0.5512 0.5537 1.0018 0.9971 0.9925 0.9880 0.9835 1.5453 1.5432 1.5412 1.5392 1.5372 2.0422 1.9992 1.9579 1.9183 1.8803 366.09 368.13 370.14 372.12 374.08 833.8 832.0 830.3 828.5 826.8 1199.9 1200.1 1200.4 T200.6 1200.9 0.5561 0.5585 0.5608 0.5631 0.-5653 0.9792 0.9750 0.9708 0.9667 0.9627 1.5353 1.5334 1.5316 1.5298 1.5280 Abs: Press. Lb Sq In. p 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 132 134 136 138 140 142 144 146 148 150 152 154 156 158 160 162 164 166 168 170 172 174 176 178 180 182 184 186 188 190 192 194 196 198 *200 205 . 210 215 220 225 ` 230 235 240 245 Reprinted by permission from Thermodynamic Properties of Steam, by J. H. Keenan and F. G. Keyes, published by John Wiley and Sons, Inc. - 28 CHAPTER 1. AIR, WATER AND STEAM Table 8. Properties of Saturated Steam: Pressure Table (Concluded) Abs. Press. Lb Sq In. P Temp F t 290 414.23 380 439.60 480 462.82 471.07 475.01 478.85 580 482.58 Specific Volume Sat. Liquid Vf 0.01865 0.018700.01875 0.01880 0.01885 0.01890 0.01899 0.01908 0.01917 0.01925 0.0193 0.0194 0.0195 0.0196 0.0197 0.0197 0.0198 0.0199 0.0200 0.0201 Sat. Vapor V, 1.8438 1.7748 1.7107 1.6511 1.5954 1.5433 1.4485 1.3645 1.2895 1.2222 1.1613 1.1061 1.0556 1.0094 0.9670 0.9278 .0.8915 0.8578 0.8265 0.7973 Enthalpy Entropy Sat. Liquid hf Evap. hfg 376.00 379.76 383.42 386.98 390.46 825.1 821.8 818.5 815.3 812.1 393.84 400.39 406.66 412.67 418.45 809.0 803.0 797.1 791.4 785.8 424.0 429.4 434.6 439.7 444.6 780.5 775.2 770.0 764.9 759.9 449.4 '454.1 458.6 463.0 467.4 755.0 750.1 745.4 740.8 736.1 Sat. Sat. Vapor Liquid hg Sf Evap. Sf, Sat. Vapor Sg 1201.1 1201.5 1201.9 1202.3 1202.6 0.5675 0.5719 0.5760 0.5801 0.5841 0.9588 0.9510 0.9436 0.9363 0.9292 1.5263 1.5229 1.5196 1.5164 1.5133 1202.8 1203.4 1203.7 1204.1 1204.3 0.5879 0.5952 0.6022 0.6090 0.6153 0.9225 0.9094 0.8970 0.8851 0.8738 1.5104 1.5046 1.4992 1.4941 1.4891 1204.5 1204.6 1204.6 1204.6 1204.5 0.6214 0.6272 0.6329 0.6383 0.6436 0.8630 0.8527 0.8426 0.8330 0.8237 1.4844 1.4799 1.4755 1.4713 1.4673 1204.4 1204.2 1204.0 1203.8 1203.5 0.6487 0.6536 0.6584 0.6631 0.6676 0.8147 0.8060 0.7976 0.7893 0.7813 1.4634 1.4596 1.4560 1.4524 1.4489 Abs. Press. Lb Sq In. p 250 260 270 280 290 300 320 340 360 380 400 420 440 460 480 500 520 540 560 580 486.21 0.0201489.75 0.0202 493.21 0.0203 0.0204 680 499.88 0.0204 0.7698 0.7440 0.7198 0.6971 0.6757 471.6 475.7 479.8 483.8 487.7 731.6 727.2 722.7 718.3 714.0 1203.2 1202.9 1202.5 1202.1 1201.7 0.6720 0.6763 0.6805 0.6846 0.6886 0.7734 0.7658 0.7584 0.7512 0.7441 1.4454 1.4421 1.4389 1.4358 1.4327 600 620 640 660 680 503.10 0.0205 506.25 0.0206 740 509.34 0.0207 512.36 0.0207 780 515.33 0.0208 0.6554 0.6362 0.6180 0.6007 0.5843 491.5 495.3 499.0 502.6 506.2 709.7 705.4 701.2 697.1 692.9 1201.2 1200.7 1200.2 1199.7 1199.1 0.6925 0.6963 0.7001 0.7037 0.7073 0.7371 0.7303 0.7237 0.7172 0.7108 1.4296 1.4266 1.4237 1.4209 1.4181 700 720 740 760 780 800 518.23 0.0209 521.08 0.0209 523.88 0.0210 526.63 0.0211 880 529.33 0.0212 0.5687 0.5538 0.5396 0.5260 0.5130 509.7 513.2 516.6 520.0 523.3 688.9 684.8 680.8 676.8 672.8 1198.6 1198.0 1197.4 1196.8 1196.1 0.7108 0.7143 0.7177 0.7210 0.7243 0.7045 0.6983 0.6922 0.6862 0.6803 1.4153 1.4126 1.4099 1.4072 1.4046 800 820 840 860 880 920 940 , 980 531.98 534.59 537.16 539.68 542.17 0.0212 0.0213 0.0214 0.0214 0.0215 0.5006 0.4886 0.4772 0.4663 0.4557 526.6 529.8 533.0 536.2 539.3 668.8 664.9 661.0 657;1 653.3 1195.4 1194.7 1194.0 1193.3 .1192.6 0.7275 0.7307 0.7339 0.7370 0.7400 0.6744 0.6687 0.6631 0.6576 0.6521 1,4020 1.3995 1.3970 1.3945 1.3921 900 920 940 960 980 1050 1100 1150 1200 544.61 0.0216 550.57 0.0218 556.31 . 0.0220 561.86 0.0221 567.22 0.0223 0.4456 0.4218 0.4001 0.3802 0.3619 542.4 550.0 557.4 564.6 571.7 649.4 639.9 630.4 621.0 611.7 1191.8 1189.9 1187.8 1185.6 1183.4 0.7430 0.7504 0.7575 0.7644 0.7711 0.6467 0.6334 0.6205 0.6079 0.5956 1.3897 1.3838 1.3780 1.3723 1.3667 1000 1050 1100 1150 1200 1250 1300 1350 1400 1450 572.42 577.46 582.35 587.10 591.73 0.0225 0.0227. 0.0229 0.0231 0.0233 0.3450 0.3293 0.3148 0.3012 0.2884 578.6 585.4 592.1 598.7 605.2 602.4 593.2 584.0 574.7 565.5 1181.0 1178.6 1176.1 1173.4 1170.7 0.7776 0.7840 0.7902 0.7963 0.8023 0.5836 0.5719 0.5604 0.5491 0.5379 1.3612 1.3559 1.3506 1.3454 1.3402 1250 1300 1350 1400 1450 1500 1600 1700 1800 1900 596.23 604.90 613.15 621.03 628.58 0.0235 0.0239 0.0243 0.0247 0.0252 0.2765 0.2548 0.2354 0.2179 0.2021 611.6 624.1 636.3 648.3 660.1 556.3 538.0 519.6 501.1 482.4 1167.9 1162.1 1155.9 1149.4 1142.4 0.8082 0.8196 0.8306 0.8412 0.8516 0.5269 0.5053 0.4843 0.4637 0.4433 1.3351 1.3249 1.3149 1.3049 1.2949 1500 1600 1700 1800 1900 2000 2200 2400 2600 2800 635.82 0.0257 649.46 0.0268 662.12 0.0280 673.94 0.0295 684.99 0.0315 0.1878 0.1625 0.1407 0.1213 0.1035 671.7 694.8 .718.4 743.0 770.1 463.4 424.4 382.7 337.2 284.7 1135.1 1119.2 1101.1 1080.2 1054.8 0.8619 0.8820 0.9023 0.9232 0.9459 0.4230 0.3826 0.3411 0.2973 0.2487 1.2849 1.2646 1.2434 1.2205 1.1946 2000 2200 2400 2600 2800 3000 3200 695.36 0.0346 705.11 0.0444 0.0858 0.0580 802.5 872.4 217'8 1020.3 0.9731 0.1885 1.1615 3000 62.0 934.4 1.0320 0.0532 1.0852 3200 3206.2 705.40 0.0503 0.0503 902.7 0 902.7 1.0580 0 1.0580 3206.2 `Reprinted by permission from Thermodynamic Properties of Steam, by J. H. Keenan and F. G. Keyes, published by John Wiley and Sons, Inc. 29 HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 Water Pressures. Pressures are often stated in feet or inches of water column. At 62 F, with ft equal to the head in feet, the pressure of a column of water is 62.383ft lb per square foot, or 0.433ft lb per square inch. A column of water 2.309 ft (27.71 in.) high exerts a pressure of one pound per square inch at 62 F. Boiling Point of Water. The boiling point of water varies with the pressure; it is lower at higher altitudes. A change in pressure will always be accompanied by a change in the boiling point, and there will be a cor responding change in the latent heat of evaporation. These values are given in Table 8. Specific Heat. The specific heat of water, or the amount of heat (Btu) required to raise the temperature of one pound of water one degree Fahren heit, varies with the temperature, but it is commonly assumed to be unity at all temperatures. Steam tables are based, on exact values, however. The specific heat of ice at 32 F is 0.492 Btu per pound. The amount of heat required to raise one pound of water at 32 F through a known temperature interval depends on the average specific heat for the temperature range. .. Sensible and Latent Heat. The heat necessary to raise the temperature of one pound of water from 32 F to the boiling point is known as the heat of the liquid or sensible heat. When more heat is added, the water begins to evaporate and expand at constant temperature until the,: water is entirely changed into steam. The heat thus added is known as the latent heat of evaporation. PROPERTIES OF STEAM Steam is water vapor which exists in the vaporous condition because sufficient heat has been added to the water to supply the latent heat of evaporation and change the liquid into vapor. This change in state takes place at a definite and constant temperature which is determined solely by the pressure of the steam. The volume of a pound of steam is the specific volume which decreases as the pressure increases; The reciprocal of this, or the weight of steam per cubic foot, is the density. (See Table 8.) Steam which is in contact with the water from which it was generated is known as saturated steam. If it contains no actual water in the form of mist or priming, it is called dry saturated steam. If this be heated and the pressure maintained the same as when it was vaporized, its temperature will increase and it will become superheated, that is, its temperature will be higher than that of saturated steam at the same pressure, , REFERENCES Temperature of Evaporation, by W. H: Carrier (A.S.H.V.E. Transactions, Vol. 24. 1918, p. 25). . The Evaporation of a Liquid into a Gas, by W. K. Lewis (A.S.M.E. Transactions. Vol. 44, 1922). Temperature of Evaporation of Water into Air, by W. H. Carrier and D. C. Lindsay (A.S.M.E. Transactions, Vol. 46, 1924). . A New Psychrometric Chart, by F. O. Urban (Refrigerating Engineering,-November 1935). - Psychrometric Charts, by Donald B. Brooks (U. S. Bureau ofStandards Miscellaneous Publication No. 143). 30 Chapter 2 REFRIGERANTS AND AIR DRYING AGENTS Properties of Refrigerant Substances, Selection Factors, Solid Adsorbents, Liquid Absorbents, Nature of Processes, Tempera ture Pressure Concentration Relations BOTH cooling and dehumidification of air are usually desirable at certain times. Cooling may be regarded as the extraction of sensible heat while dehumidification necessitates the removal of latent heat. By a suitable selection and combination of methods and equipment these two processes may be accomplished simultaneously or they may be secured independent of each other and at different times as desired. On occasion, the desired result can be secured by extracting sensible heat only while in other cases drying alone will produce the end conditions sought. Suitable substances must be available for use in every particular case. Generally, when both cooling and dehumidification are sought current practice makes use of artificially produced refrigeration in some form. The substances used as the heat-carrying agents in these applications are called refrigerants. Air drying agents are substances which permit dehumidification of air as a process separate and independent of the extraction of sensible heat from it. Refrigerants and air drying agents are treated separately in this chapter where the aim is to present a statement of the properties of these substances which are of especial importance in air conditioning work. Little mention is made here of methods, systems, or equipment whereby these substances may be applied, which infor mation may be found in Chapter 24. ' REFRIGERANTS Since air cooling and dehumidification are frequently accomplished by evaporating a liquid under circumstances which will permit the heat necessary to be extracted from the air, the refrigerants are substances which are capable of being changed into liquids or vapors within workable temperature and pressure ranges. There are many substances which might be so used but in practice the choice is limited by a wide variety of considerations including availability, cost, safety, chemical stability and adaptability to the type of refrigerating system to be used. In this chapter detailed consideration is limited to six substances, viz: ammonia, carbon dioxide, dichlorodifluoromethane (Fit), methyl 31 HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 Table 1. Properties of Ammonia Temp. F Press. Lb per Sq In. liquid Vapor 0 2 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 39 40 41 42 44 46 48 50 52 ' 54 56 58 60 62 64 66 68 70 72 74 . 76 <78 .80 ' 82 . . 84 . 86 88 90 92 94 96 98 100 102 104 106 . 108 . 110 112 114 116 118 120 122 124 126 128 30.42 31.92 33.47 34.27 35.09 36.77 38.51 40.31 42.18 44.12 46.13 48.21 50.36 52.59 54.90 57.28 59.74 62.29 64.91 67.63 70.43 71.87 73.32 74.80 76J1 79J8 82JS 85.82 89.19 92.66 96.23 99.91 103.7 107.6 111.6 115.7 120.0 124.3 128.8 133.4 138.1 143.0 147.9 153.0 158.3 163.7 169.2 174.8 180.6 186.6 192.7 198.9 205.3 211.9 218.6 225.4 232.5 239.7 247.0 254.5 262.2 270.1 278.2 286.4 294.8 303.4 312.2 321.2 0.02419 0.02424 0.02430 0.02432 0.02435 0.02440 0.02446 0.02451 0.02457 0.02462 0.02468 0.02474 0.02479 0.02485 0.02491 0.02497 0.02503 0.0250S 0.02514 0.02521 0.02527 0.02530 0.02533' 0.02536 0.02539 0.02545 0.02551 0.02558 0.02564 0.02571 0.02577 0.02584 0.02590 0.02597 0.02604 0.02611 0.02618 0.02625 0.02632 0.02639 0.02646 0.02653 0.02661 0.02668 0.02675 0.02684 0.02691 0.02699 0.02707 0.02715 0.02723 0.02731 0.02739 0.02747 0.02756 0.02764 0.02773 0.02782 0.02790 0.02799 0.02808 0.02817 0.02827 0.02836- 0.02846 0.02855 0.02865 0.02875 9.116 8.714 8-333 8.150 7.971 7.629 7-304 6.996 6.703 6.425 6.161 5.910 5.671 5.443 5.227 5.021 4.825 4.637 4.459 4.289 4.126 4.048 3.971 3.897 3.823 3.682 3.547 3.418 3.294 3.176 3.063 2.954 2.851 2.751 2.656 2.565 2.477 2.393 2.312 2.235 2.161 2.089 2.021 1.955 1.892 1.831 1.772 1.716 1.661 1.609 1.559 1.510 1.464 1.419 1J7S 1.334 1.293 1.254 1.217 1.180 1.145 1.112 1.079 1.047 1.017 0.987 0.958 0.931 Heat Content and Enthopt Taken Fbom --40 F Heat Coatent Entropy 100 F Superheat 200 F Superheat Liquid 42.9 45.1 47.2 48.3 49.4 51.6 53.8 56.0 58.2 60.3 62.5 64.7 66.9 69.1 71.3 73.5 75.7 77.9 80.1 82.3 84.6 85.7 86.8 87.9 89.0' 91.2 93.5 95.7 97.9 100.2 102.4 104.7 106.9 .109.2 111.5 113.7 116.0 118.3 120.5 122.8 125.1 127.4 129.7 132.0 134.3 136.6 138.9 141.2 143.5 145.8 148.2 150.5 152.9 155.2 157.6 159.9 162.3 164.6 167.0 169.4 171.8 174.2 176.6 179.0 181.4 183.9 186.3 188.8 Vapor liquid Vapor Ht Cl Entropy HL Ct Entropy 611.8 612.4 613.0 613.3 613.6 614.3 614.9 615.5 616.1 616.6 617.2 617.8 618.3 618.9 619.4 619.9 620.5 621.0 621.5 622.0 622.5 622.7 623.0 623.2 623.4 623.9 624.4 624.8 625.2 625.7 626.1 626.5 626.9 627.3 627.7 628.0 628.4 628.8 629.1 629.4 629.8 630.1 630.4 630.7 631.0 631.3 631.5 631.8 632.0 632.2 632.5 632.6 632.9 633.0 633.2 633.4 633.5 633.6 633.7 633.8 633.9 634.0 634.0 634.0 634.0 634.0 633.9 633.9 0-0975 0.1022 0.1069 0.1092 0.1115 0.1162 0.1208 0.1254 0.1300 0.1346 0.1392 0.1437 0.1483 0.1528 0.1573 0.1618 0.1663 0.1708 0.1753 0.1797 0.1841 0.1863 0.1885 0.1908 0.1930 0.1974 0.2018 0.2062 0.2105 0.2149 0.2192 0.2236 0.2279 0.2322 0.2365 0.2408 0.2451 0.2494 0.2537 0.2579 0.2622 0.2664 0.2706 0.2749 0.2791 0.2833 0.2875 0.2917 0.2958 0.3000 0.3041 0.3083 0.3125 0.3166 QJ2Q7 0.3248 0.3289 0.3330 0.3372 0.3413 0.3453 0-3495 0.3535 0.3576 0-3618 0.3659 0.3700 0.3741 1.3352 1.3312 1.3273 1.3253 1.3234 666.8 667.6 668.4 668.8 669.3 1.3195 1.3157 1.3118 0081 0043 670.1 670.9 . 671.7 672.5 673.4 1.3006 1.2969 1.2933 1.2897 1.2861 674.2 675.0 675.8 676.6 677.3 1.2825 1.2790 1.2755 1.2721 1.2686 678.1 678.9 679.7 680.4 681.2 1.2652 1.2635 1.2618 . 1.2602 1.2585 681.9 682.3 682.7 683.1 683.4 1.2552 1.2519 1.2486 1.2453 1.2421 684.2 684.9 685.6 686.4. 687.1 1.2389 L2357 1.2325 1.2294 1.2262 687.8 688.5 689.2 689.9 690.6 1.2231 1.2201 1.2170 1.2140 1.2110 691.3 691.9 692.6 693-3 694.0 1.2080 1.2050 1.2020 1.1991 1.1962 694.6 695.3 695.9 696.6 697.2 . 1.1933 1.1904 1.1875 1.1846 1.1818 697.8 698.5 699.1 699.7 700.3 1.1789 1.1761 1.1733 1.1705 1.1677 700.9 701.5 702.1 702.7 703.3 L1649 1.1621 1.1593 1.1566 1.1538 703.8 704J 705.0 705.5 706.1 1.1510 1.1483 1.1455 1.1427 706.6 707J2 707.7 708.2 1.1400 1.1372 1.1344 1.1316 .708.6 709.1 709.6 710.0 1.4439 1.4400 1.4360 1.4340 1.4321 720.3 721.2 722.2 722.6 723.1 1.4281 1.4242 1.4205 1.4168 1.4130 724.1 725.0 725.9 726.8 727.8 1.4093 1.4056 1.4021 1.3985 1.3950 728.7 729.6 730.5 731.4 732.4 1.3914 1.3879 1.3846 1.3812 1.3779 733-3 734.2 735.1 736.0 736.8 1.3745 1.3729 1.3712 1.3696 1-3680 737.7 738.2 738.6 739.0 739.5 1.3648 1.3616 1-3584 1.3552 U521 740.4 741.3 742.2 743.1 744.0 1.3491 1-3460 1.3430 1.3399 1.3370 744.8 ' 745.7 746,5 747.4 748.2 1.3341 1.3312 1.3283 1.3254 1.3226 749.1 ' 749.9 750.8 751.6 752.4 1.3199 1-3171 1.3144 1.3116 1.3089 753.3 7S4.1 755.0 755.8 756.6 1.3063 1.3040 1.3010 1.2983 1.2957 757.4 758-3 759.1 759.9 760.7 1.2932 1.2906 1.2881 1.2855 1.2830 761.5 762.2 763.0 763.8 764.6 1.2805 1.2780 1.2755 1.2731 1.2703 765.3 766.1 766.9 767.6 768.3 1.2684 1.2661 1.2636 1.2612 769.1 769.8 770.5 771-3 1.2587 1.2563 1.2538 1.2513 772.0 772.8 773.5 774.2 1.5317 1.5277 1.5236 1.5216 1.5196 1.5155 1.5115 1.5077 1.5039 1.5001 1.4963 1.4925 1.4889 1.4853 1.4816 1.4780 1.4744 1.4710 1.4676 1.4643 1.4609 1.4592 1.4575 r 1.4559 1.4542 1.4510 . 1.4477 1.4445 ! 1.4412 1.4382 1.4351 1.4321 1.4290 1.4260 1.4231 1.4202 1.4172 1.4143 1.4114 1.4086 1.4059 1.4031 1.4004 1.3976 1.3949 1.3923 1.3896 1.3870 ` 1-3843 . 1.3818 1.3793 1.3768 1-3743 1.3718 1.3693 1.3668 1-3643 1.3619 13596 1.3573-' 1-3550 1.3527 1.3503 1.3479 . 1-3455 1.3431 1-3407 1-3383 32 CHAPTER 2. REFRIGERANTS AND AIR DRYING AGENTS .1 Table 2. Properties of Dichlorodifluoromethane(Fh) Sat. Abs. . Press. Volume ' Heat CONTENT AND ENTROPT TAKEN FbOM --40 F Heat Content Entropy' 25 F Superheat SoFSu perheat F Sq In. liquid Vapor liquid Vapor liquid Vapor - Ht. Ct. Entropy Ht Ct. Entropy ----- ft-- " * 27.05 > 33.08 26 40.07 36 48.13 49.88 .42 5331 55.40 52 62 . 68 72 74 76 78 82 84 86 63.49 65.63 67.84 70.10 ' 72.41 74.77 77.20 79.67 82.24 8432 87.50 90.20 93.00 9535 98.76 101.70 1043 107.9 92 117.7 1213 96 1243 too98 128.0 131.6 102 135.3 ' 104 139.0 166 1423 108 1463 110 150.7 112 1543 . 114 158.9 116 163.1 118 167.4 120 1713 122 176.2 124 1803 126 185.4 128 190.1 130 194.9 132 1993' 134 204.8 136 209.9 138 215.0 140 220.2 0.0110 0.0110 ; 0.0111 1 0.0111 0.0111 0.0112 0.0112 0.0112 0.0112 0.0113 0.0113 0.0113 0.0113 0.0114 0.0114 0.0115 0.0115 0.0115 0.0116 0.0116 0.0116 0.0116 0.0116 0.0116 0.0117 0.0117 0.0117 0.0118 0.0118 0.0118 0.0119 00119 0.0119 . 0.0120 0.0120 0.0120 0.0121 0.0121 0.0121 0.0122 0.0122. 0.0123 0.0123 0.0123 0.0124 0.0124 0.0124 0.0125 0.0125 0.0126 0.0126 0.0126 0.0127 0.0127 0.0128 0.0128 0.0129 0.0129 0.0130 0.0130 0.0131 0.0131 0.0132 0.0132 0.0133 0.0133 0.0134 0.0134 0.0135 0.0135 0.0136 0.0137 0.0138 1.637- . 1374 1314 * 1.485 1.457. 1.403: . 1351! 1J01 . 1.253 1.207 1.163 1.121 1.081. 1.043 1.007 0.973 0.939. 0.908 0377 0.848 0.819 0.806 0.792 0.779 . 0.767 0.742 0.718 0.695 0.6730.652 0.632 0.612 0393 0.575 . 0357 0340 0324 0308 0.493 0.479 0.464 0.451 0.438 0.425 0.413 0.401 0389 0378 0368 0357 0347 0.338 0328 0319 0310 0302 0.293 0.285 0.277 0.269 0.262 0.254 0.247 . 0.240 0.233 0.227 0.220 0.214 0.208 0.202 0.196 0.191 0.185 0.180 8.25 8.67 9.10 932 : 9.53 ' 78.21 78.44 78.67 78.79 78.90 9.96 1039 1032 11.26 11.70 79.13 7936 79.59 79.82 80.05 12.12 12.55 13.00 13.44 13.88 .80.27 80.49 80.72 80.95 81.17 1432 14.76 . 15.21 15.65 16.10 8139 81.61 81.83 82.05 82.27 1635 16.77 17.00 17.23 17.46 82.49 82.60 82.71 82.82 82.93 17.91 18.36 18.82 19.27 19.72 83.15 8336 83.57 83.78 83.99 20.18 20.64 ,21.11 21.57 22.03 84.20 84.41 84.62 84.82 85-02 22.49 22.95 23.42 23.90 2437 85.22 8S.42 85.62 85.82 86.02 24.84 2532 25.80 26.28 26.76 86.22 86.42 86.61 86.80 86.99 27.24 27.72 28.21 28.70 29.19 87.18 8737 87.56 87.74 87.92 . 29.68 30.18 30-67 31.16 31.65 88.10 88.28 88.45 88.62 88.79 32.15 32.65 33.15 33.65 34.15 88.95 S9.ll 89.27 89.43 89.58 34.65 35.15 35.65 36.16 36.66 89.73 89.87 90.01 90.15 9028 37.16 . 37.67 38.18 38.69 39.19 90.40 90.52 90.64 90.76 9036 39.70 40.21 40.72 41.24 90.96 91.06 91.15 91.24 0.01869 0.01961 0.02052 032097 0.02143 0.17091 0.17075 0.17060 0.17052 0.17045 . 81.71 81.94 82.17 82.29 .82.41 0.02235 0.02328 0.02419 0.02510 0.02601 6.17030 Q.17015 0.17001 0.16987 0.16974 82.66 82.90 83.14 83.38 ` 83.61 0.02692 0.02783 0.02873 0.02963 0.03053 0.16961 0.16949 0.16938 0.16926 0.16913 83.85 84.09 84.32 84.55 84.79 0.03143 0.03233 0.03323 0.03413 003502 0.16900 0.16887 0.16876 0.16865 0.16854 85.02 85.25 85.48 85.71 .8S.95 0.03591 0.03635 0.03680 0.03725 0.03770 0.16843 0.16838 0.16833 0.16828 0.16823 86.18 .86.29 86.41 86.52 86.64 0.03859 0.03948 0.04037 0.04126 0.04215 0.16S13 0.16803 0.16794 0.16785 0.16776 86.86 87.09 87.31 87.54 87.76 0.04304 0.04392 0.04480 0.04568 0.04657 0.16767 0.16758 0.16749 0.16741 0.16733 87.98 88.20 88.42 88.64 88.66 0.04745 0.04833 0.04921 0.05009 0.05097 0.16723 0.16717 0.16709 0.16701 0.16693 89.07 89.29 89.50 89.72 89.93 0.05185 0.05272 0.05359 0.05446 0.05534 0.16685 0.16677 0.16669 0.16662 0.16655 90.14 90.36 90.57 90.78 90.98 0.05621 0.05708 0.05795 0.05882 0.0S969 0.16648 0.16640 0.16632 0.16624 0.16616 91.18 9U7 91.57 91.77 91.97 0.06056 0.06143 0.06230 0.06316 0.06403 0.16608 0.16600 0.16592 0.16584 0.16576 92.16 92.36 92^5 92.75 92.93 0.06490 0.06577 0.06663 0.06749 0.06836 0.16568 0.16560 0.16551 0.16542 0.16533 93.11 93.30 93.48 93.66 93.82 0.06922 0.07008 0.07094 0.07180 0.07266 0.16524 0.16515 0.16S05 0.16495 0.16484 93.98 94.15 94.31 94.47 94.63 0.07352 0.07437 0.07522 0.07607 0.07691 0.16473 0.16462 0.16450 0.16438 0.16425 94.78 94.94 9S.09 95.25 95.41 0.07775 0.07858 0.07941 0.08024 0.16411 0.16396 0.16380 0.16363 95.56 95.72 95.87 96.03 0.17829 0.17812 0.17795 0.17786 0.17778 85.26 85-51 85.76 85-89 86.01 0.18547 ' 0.18529 0.18511 0.18502 0.18494 0.17763 0.17747 0.17733 0.17720 0.17706 86.26 86.51 86.76 87.01 . 87.26 0.18477 0.18460 0.18444 0.18429 0.18413 0.17693 0.17679 0.17666 0.17652 0.17639 87.51 87.76 88.00 88.24 88.49 0.18397 0.18382 0.18369 0.18355 0.18342 0.17625 0.17612 0.17600 0.17589 0.17577 88.73 88.97 89.21 89.45 89.68 0.18328 0.18315 0.18303 0.18291 0.18280 0.17566 0.17560 0.17554 0.17549 0.17544 89.92 90.04 90.16 90.28 90.40 0.18268 0.18262 0.18256 0.18251 0.18245 0.17534 0.17525 0.17515 0.17505 0.17496 90.65 90.89 91.14 91.38 91.61 0.18235 0.18224 0.18214 0.18203 0.18193 0.17486 0.17477 0.17467 0.17458 0.17450 91.83 92.06 92.28 92.51 92.74 0.18184 0.18174 0.18165 0.18155 0.18147 0.17442 0.17433 0.17425 0.17417 0.17409 92.97 93.20 93.43 93.66 93.99 0.18139 0.18130 0.18122 0.18114 0.18106 0.17402 0.17394 0.17387 0.17379 0.17372 94.12 94.34 94.57 94.80 95.01 0.18098 018091 0.18088 0.18075 0.18068 0.17365 0.17358 0.17351 0.17344 0.17337 95.22 95.44 95.65 95.86 96.07 0.18061 0.18054 0.18047 0.18040 0.18033 0.17330 0.17322 0.17315 0.17308 0.17301 96.28 96.50 96.71 96.92 97.12 0.18026 0.18018 0.18011 0.18004 0.17998 0.17294 0.17288 0.17281 0.17274 0.17266 97.32 97.53 97.73 97.93 98.11 0.17993 0.17987 0.17982 0.17976 0.17969 0.17258 0.17249 0.17241 0.17233 0.17224 98.29 98.48 98.66 98.84- 99.01 0.17961 0.17954 0.17946 0.17939 0.17931 0.17215 0.17206 0.17196 0.17186 0.17176 99.18 99.35 99.53 99.70 99.87 0.17922 0.17914 0.17906 0.17897 0.17889 0:17166 0.17156 0.17145 0.17134 100.04 100.22 100.39 100.55 0.17881 0.17873 0.17864 0.17856 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 3. Properties of Methyl Chloride Sat. Temp. F Abs. Press. Lb FEB SqIn. Volume liquid Vapor 0 18.73 0.0162 5.052 2 19.60 0.0162 4.856 4 20.47 0.0163 4.661 5 20.91 0.0163 4.563 6 2U9 0.0163 4.476 8 22.34 0.0164 4.303 10 23.30 0.0164 4.129 12 24.38 0.0164 3.984 14 25.46 0.0164 3.839 16 26.55 0.0165 3.693 18 27.63 0.0165 3.548 20 28.71 0.0166 3.403 22 29.98 0.0166 3.288 24 31.25 0.0166 3.172 26 32.53 0.0167 3.057 28 33.80 0.0167 2.941 30 35.07 0.0168 2.826 32 36.55 0.0168 2.734 34 38.03 0.0169 2.642 36 39.51 0.0169 2.549 38 40.99 0.0169 2.457 39 41.73 0.0170 2.411 40 42.47 0.0170 2.365 41 43.33 0.0170 2J28 42 44.18 0.0171 2.290 44 45.89 0.0171 2.216 46 47.61 0.0171 2.141 48 49.32 0.0172 2.067 SO 51.03 0.0172 1.992 52 53.00 0.0172 1.931 54 54.97 0.0173 1.870 56 56.94 0.0173 14110 58 58.91 0.0173 1.749 60 60.88 0.0174 1.688 62 63.13 0.0174 1.638 64 65.37 0.0174 1.588 66 67.62 0.0175 1.539 68 69.86 0.0175 1.489 70 72.11 0.0176 1.439 72 74.66 0.0176 1.398 74 77.21 0.0177 76 . 79.76 0.0177 78 82.31 0.0178 80 84.86 0.0178 82 87.74 0.0178 1.357 1.315 1.274 1.233 1.199 84 90.62 0.0179 86 93.50 0.0179 88 96.38 0.0180 90 99.26 0.0180 92 102.49 0.0180 1.165 1.130 1.096 1.062 1.033 94 105.72 0.0181 96 108.94 0.0181 98 112.17 0.0182 100 115.40 0.0182 102 119.00 0.0183 1.005 0 9764 0.9478 0.9193 0.8952 104 122.60 0.0183 106 126.20 0.0184 108 129.80 0.0184 110 133.40 0.0185 112 137.42 0.0185 0.8712 0.8471 0.8231 0.7990 0.7786 114 141.44 0.0185 116 145.46 0.0186 118 149.48 0.0186 120 153.50 0.0187 0.7583 0.7379 0.7176 0.6972 Heat Content and Entbopt Taken From -40 F Heat Content Entropy 100 F Superheat 200 F Superheat liquid Vapor liquid Vapor HtCL Entrap; HL Ct Entropy 14.4 192.4 0.0328 0.4197 215.6 0.467 237.2 0.507 15.1 193.1 0.0344 0.4196 216.2 0.466 237.7 0.505 15.8 193.8 0.0360 0.4195 216.7 0.465 238.2 0.504 16.2 194.1 0.0368 0.4195 217.0 0.464 238.5 0.503 16.6 194.4 0.0376 0.4194 217.3 0.464 238.8 0.502 17.3 18.1 18.8 19.6 20.3 195.1 195.8 196.3 196.7 197.2 0.0391 0.0407 0.0423 0.0439 0.0454 0.4193 0.4192 0.4184 0.4176 0.4168 217.9 218.5 219.0 219.5 220.0 0.463 0.463 0.462 0.462 0.461 239.4 240.0 240.5 241.0 241.5 0.S01 0.500 0.499 0.498 0.498 21.1 197.6 0.0472 0.4160 220.5 0.461 242.0 0.497 21.8 198.1 0.0486 0.4152 221.0 0.460 242.5 0.496 22.5 198.5 0.0501 0.4148 221.5 0.459 243.0 0.495 23.3 198.9 0.0516 0.4143 222.0 0.459 243.6 0.495 24.0 199.3 0.0532 0.4139 222.4 0.458 244.1 0.494 24.8 199.7 0.0547 0.4134 222.9 0.458 244.7 0.494 25.5 200.1 0.0562 0.4130 223.4 0.457 245.2 0.493 26.2 200.5 0.0577 0.4124 223.9 0.456 245.7 0.492 27.0 200.9 0.0592 0.4118 224.3 0.455 246.2 0.492 27.7 201.4 0.0607 0.4111 224.8 0.455 246.7 0.491 28.5 28.8 29.2 29.6 29.9 201.8 202.0 202.2 202.4 202.6 0.0622 0.0629 0.0637 0.0644 0.0651 0.4105 0.4102 0.4099 0.4096 0.4093 225.2 225.5 225.7 225.9 226.1 0.454 0.453 0.453 0.453 0.452 247.2 247.4 247.7 248.0 248.3 0.491 0.490 0.490 0.490 0.489 30.7 31.4 32.2 32.9 33.7 203.0 203.3 203.7 204.1 204.4 0.0666 0.0680 0.0695 0.0709 0.0724 0.4087 0.4081 0.4075 0.4069 0.4063 226.6 227.0 227.5 227.9 228.2 0.451 0.451 0.450 0.449 0.448 248.8 249.4 249.9 250.5 251.0 0.489 0.488 0.488 0.487 0.486 34.4 35.2 35.9 36.7 37.4 204.7 205.1- 205.4 205.7 206.0 0.0739 0.0754 0.0769 0.0784 0.0798 0.4056 0.4050 0.4043 0.4037 0.4030 228.6 228.9 229.3 229.6 229.9 0.448 0.447 0.447 0.446 0.445 251.5 252.0 252.5 253.0 253.5 0.486 0.485 0.485 0.484 0.483 38.2 38.9 39.7 40.4 41.1 206.3 206.6 206.9 207.2 207.5 0.0812 0.0827 0.0841 0.0855 0.0869 0.4024 0.4017 0.4011 0.4004 0.3998 230.3 230.6 231.0 231.3 231.6 0.444 0.443 0.442 0.441 0.440 254.0 254.5 255.0 255.5 256.0 0.483 0.482 0.482 0.481 0.480 41.9 42.6 43.4 44.1 44.8 207.7 208.0 208.2 208.5 208.7 0.0883 0.0898 0.0912 0.0926 0.0940 0.3992 0.3985 0.3979 0.3973 0.3967 232.0 232.3 232.7 233.0 233.3 0.439 0.439 0.438 0.437 .0.436 256.5 256.9 257.4 257.9 258.4 0.480 0.479 0.479 0.478 0.478 45.6 46.3 47.1 47.8 48.6 209.0 209.2 209.5 209.7 209.9 0.0953 0.0967 0.0980 0.0994 0.1008 0.3960 0.3954 0.3947 0.3941 0.3935 233.6 233.9 234.2 234.5 234.8 0.435 0.435 0.434 0 433 0.433 258.9 259.4 259.9 260.4 260.8 0.477 0.477 0.476 0.476 0.476 49.3 50.1 50.8 51.6 52J 210.2 210.4 210.7 210.9 211.1 0.1022 0.1035 0.1049 0.1063 0.1076 0.3929 0.3922 0.3916 0.3910 0.3903 235.1 235.4 235.7 236.0 236.4 0.432 0.432 0.431 0.431 0.430 261.2 261.6 262.0 262.4 262.8 0.475 0.475 0.474 0.474 0.474 53.1 53.8 54.6 55.3 56.1 21U 211.4 211.6 211.8 212.0 0.1090 0.1103 0.1117 0.1130 0.1144- 0J897 0.3890 0.3884 0.3877 0.3871 236.8 237.1 237.5 237.9 238.1 0.430 0.429 0.429 0.428 0.427 263.2 263.5 263.9 264.3 264.6 0.473 0.473 0.472 0.472 0.471 56.8 57.6 58.3 59.1 212.2 212.4 212.6 212.8 0.1157 0.1171 0.1184 0.1198 0.3864 0.3858 0.3851 0.3845 238.3 238.6 238.8 239.0 0.427 0.426 0.426 0.425 264.8 265.1 265.3 265.6 - 0.470 0.470 0.469 0.468 34 CHAPTER 2. REFRIGERANTS AND AIR DRYINC AGENTS Table 4. Properties of Carbon Dioxide Sat. Temp. F Abs. Press. La feb SlN. Volume liquid Vapor Heat Content and Enteopy Taken From --40 F Heat Content Entropy 50 F Superheat 100 F Superheat Liquid Vapor Liquid Vapor Ht. Ct. Entropy Ht. Ct. Entropy 2 . 0.01570 0.29040 18.8 138.9 0.0418 0.3024 153.7 0.3342 167.5 0.3612 0.01579 0.28030 19.8 138.8 .0.0440 0.3014 153.7 0.3330 167.6 0.3600 0.01588 0.27070 20.8 138.8 0.0461 0.3005 153.7 0.3318 167.7 0.3588 0 01592 0.26610 21.3 138.8 0.0472 0.3000 153.7 0.3312 167.7 0.3582 6 337.4 0.01596 0.26140 21.8 .138.7 0.0483 0.2994 153.7 0.3306 167.8 0.3576 0.01605 0.25260 22.9 * 138.7 0.0504 0.2982 153.7 0.3293 167.9 0.3563 0.01614 0.24370 24.0 138.7 0.0526 0.2970 153.7 0.3281 168.0 0.3550 0.01623 0.23540 25.0 138.6 0.0548 0.2958 153.7 0.3270 168.1 0.3538 0.01632 0.22740 26.1 138.6 0.0571 0.2946 153.7 0.3259 168.2 0.3526 16 396.2 0.01642 0.21970 27.2 . 138.5 0.0593 0.2933 153.7 0.3249 168.3 0.3513 0.01652 0.21210 28.3 138.4 0.0616 0.2921 153.7 0.3238 168.5 0.3501 0.01663 0.20490 29.4 138.3 0.0638 0.2909 153.7 0.3227 168.6 0.3489 0.01673 0.19790 30.5 138.2 0.0662 0.2897 153.7 0.3214 168.7 0.3479 0.01684 0.19120 31.7 138.1 0.0686 0.2885 153.7 0.3202 168.8 0.3470 26 462.2 0.01695 0.18460 32.9- 138.0 0.0710 0.2873 153.7 0.3189 168.9 0.3460 476.3 0.01707 0.17830 34.1 137.9 0.0734 0.2861 153.7 0.3177 169.0 0.3451 001719 0.17220 35.4 137.8 0.07S8 0.2849 153.7 0.3164 169.1 0.3441 505.5 0.01731 0.16630 36.7 137.7 0.0781 0.2834 153.7 0.3158 169.2 0.3431 36 522.6 536.0 0.01744 0.01759 0.16030 0.15500 37.9 39.1 137.4 137.2 0.0804 0.2820 0.0828 0.2805 153.7 0.3151 153.7 ^ 0.3145 169.3 169.4 0.3421 0.3411 551.7 0.01773 0.14960 40.4 136.9 0.0851 0.2791 153.7 . : 6.3138 169.5 0.3401 559.7 0.01780 0.14700 41.0 136.8 0.0862 0.2783 153.7*; ,0.3135 169.5 0.3396 567.8 0.01787 0.14440 41.7 136.7 0.0874 0.2776 153.7: 0.3132 169.6 0.3391 576.0 0.01794 0.14185 42.3 136.5 0.0887 0.2768 153.7. 0.3127 169.6 0.3386 42 584.3 0.01801 0.13930 42.9. 136.3 0.0899 0.2761 153.7 0.3122 169.7 0.3381 601.1 0.01817 618.2 0.01834 0.13440 0.12970 44.3 45-6 136.1 135.7 0.0924 0.2745 0.0950 0.2730 153.7 153.7 0.3112 0.3101 169.8 169.9 0.3371 0.3362 50 52 635.7 653.6 671.9 0.01851 0.01868 0.01887 0.12500 0.12050 0.11610 47.0 48.4 49.8 135.4 135.0 134.5 0.0975 0.1000 0.1027 0.2714 0.2699 0.2681 153.7 153.7 153.7 0.3091 0.3081 0.3069 170.0 170.1 170.2. 0.3352 0.3342 0.3333 690.6 0.01906 6.11170 51.2 133.9 0.1054 0.2663 153.7 0.3057 170.3 0.3324 56 58 709.5 7288 0.01927 0.01948 0.10750 . 52.6 0.10340 54.0 .133.4 0.1081 0.2644 132.7 0.1108 0.2626 153.7 153.7 0.3046 0.3034 170.5 0.3315 170.6 0.3306 60 -748.6 0.01970 0.09940 55.5 132.1 0.1135 0.2608 153.7 0.3022 170.7 0.3297 62 769.0 0.01995 0.09545 57.0 13L3 0.1164 0.2584 153.7 0.3012 170.8 0.3289 64 66 68 70 789.4 0.02020 0.09180 58.6 130.6 0.1194 0.2560 153.7 0.3002 170.9 0.3281 810.3 0.02048 . 0.08800 602 129.7 0.1223 0.2535 153.7 0.2991 171.0 0.3273 831.6 0.02079 0.08422 61.9 128.7 0.1253 0.2511 153.7 0.2981 171.1 0.3265 853.4 0.02112 0.08040 63.7 127.5 0.1282 0.2487 153.7 0.2971' 171.2 0.3257 72 875.8 0.02152 0.07654 65.5 126.0 0.1321 0.2450 153.7 0.2962 171.3 .0.3250 74 76 , 78 80 82 898.2 921.3 944.8 968.7 993.0. 0.02192 0.02242 0.02300 0.02370 0.02456 0.07269 0.06875 0.06473 0.06064 0.05648 67.3 69.4 71.6 : 73.9 76.4 124.5 122.8 120.9 118.7 116.6 0.1360 0.1398 0.1437 0.1476 0.1578 0.2414 0.2377 0.2341 0.2304 0.2195 153.7 153.7 153.7 153.7 153.7 0.2953 0.2945 0.2936 0.2927 0.2920 171.4 171.5 171.6 171.7 173.8 0.3242 0.3235 0.3227 0.3220 0.3215 84 1017.7 0.02553 86 1043.0 0.02686 87.8 1069.9 0.03454 0.05223 79.4 0.04789 83.3 0.03454 97.0 113.9 110.4 97.0 0.1679 0.1781 0.1880 0.2087 0.1978 0.18S0 153.7 153.7 153.7 0.2914 0.2907 0.2901. 176.0 178.2 180.1 0.3209 0.3204 0.3199 chloride, Water, and monofluorotrichloromethane (Fn), for each of which a table is presented. Each table gives the principal physical properties of the saturated substance, and all are arranged in uniform fashion. In each case columns are included which give the heat content and entropy of the superheated vapor at two selected points. Tables 1, 2, 3 and 4 which include the. refrigerants much used in reciprocating and rotary mechanical compression systems have a 2 F temperature interval. As water and fu are much used in centrifugal compression systems the temperature interval in Tables 5 and 6 is 5 F. 35 HEATING VENTILATINC AIR CONDITIONING CUIDE 1940 Table 5. Properties of Monofluorotrichlorombthane (Fn) 8at. Temp. F Abs. La pee So In. Volume Liquid Vapor Heat Content and Entbopt Taken From -40 F Heat Content Entropy 25 F Superheat 50 F Superheat Liquid Vapor- liquid Vapor HtCt Entropy Ht Ct Entropy 0 2.59 0.01020 13.700 7.81 90.4 0.0178 0.1975 93.9 0.2049 97.4 0.2120 5 2.96 0.01024 12.100 8.81 91.2 0.0200 0.1974 94.7 0.2047 98.2 0.2117 10 3.38 0.01028 10.700 9.82 92.0 0.0222 0.1973 95.5 0.2045 99.0 0.2114 15 3.85 0.01032 9.530 10.80 92.8 0.0243 0.1971 96.3 0.2043 99.8 0.2111 20 4.36 0.01036 8.490 11.90 93.7 0.0264 0.1970 97.2 0.2041 100.7 0.2109 25 4.94 0.01040 7.580 12.90 94.5 0.0286 0.1969 98.0 0.2039 101.5 0.2107 30 5.57 0.01045 6.770 13.90 95.3 0.0307 0.1969 98.8 0.2038 102.3 0.2105 35 6.27 0.01049 6.080 14.90 96.1 0.0328 0.1968 99.6 0.2037 103.1 0.2103 40 7.03 0.01053 5.460 16.00 96.8 0.0349 0.1968 100.3 0.2036 103.8 0.2101 45 7.88 0.01057 4.920 17.00 97.6 0.0370 0.1967 101.1 0.2035 104.6 0.2099 50 8.79 0.01062 4.440 18.10 98.4 0.0391 0.1967 101.9 0.2034 105.4 0.2098 55 9.80 0.01066 4.020 19.10 99.2 0.0412 0.1967 102.7 0.2033 106.2 0.2097 60 10.90 0.01071 3.640 20.20 100.0 0.0432 0.1967 103.5 0.2033 107.0 0.2096 65 12.10 0.01076 3.300 21.30 100.8 0.0453 0.1967 104.3 0.2032 107.8 0.2094 70 13.40 0.01081 3.000 22.40 101.5 0.0473 0.1967 105.0 0.2032 108.5 0.2093 75 14.80 0.01086 2.740 23.50 102.2 0.0493 0.1967 105.7 0.2031 109.2 0.2092 80 16.30 0.01091 2.500 24.50 102.9 0.0513 0.1966 106.4 0.2030 109.9 0.2090 85 17.90 0.01096 2.280 25.60 103.6 0.0533 0.1966 107.1 0.2029 110.6 0.2089 90 19.70 0.01101 21090 26.70 104.4 0.0553 0.1966 107.9 0.2028 111.4 0.2088 95 21.60 0.01106 1.918 27.80 105.1 0.0573 0.1966 108.6 0.2028 112.1 0.2087 100 23.60 0.01111 1.761 28.90 105.7 0.0593 0.1965 109.2 0.2027 112.7 0.2085 105 25.90 0.01116 1.620 30.10 106.4 0.0613 0.1965 109.9 0.2026 113.4 0.2084 Example 1. What is the heat content above --40 F of 2.5 lb of ammonia when under a pressure of 92.9 lb per square inch gage and a temperature of 160 F? Solution. First determine the condition of the ammonia at the stated temperature and pressure. Do this by finding the absolute pressure which in this case is 92.9 lb gage plus 14.7 or 107.6 lb per square inch absolute. From Table 1 note that the satu ration temperature at this pressure is 60 F. Therefore, the ammonia is superheated 100 F, and the total heat per pound can be read directly from the Table as 689.9 Btu. In the 2.5 lb of ammonia there are 2.5 X 689.9, or 1724.75 Btu. Example S. What volume is necessary to accommodate 0.27 lb of saturated Fa vapor when compressed to 99.6 lb gage? . Solution. The absolute pressure is 99.6 plus 14.7 or 114.3 lb. In Table 2 find that one pound of Fa vapor saturated occupies 0.368 cu ft. Then the 0.27 lb would occupy 0.27 X 0.368, or 0.099 cu ft. Example S. How much heat would be removed from air passing over a coil through which 2 lb of methyl chloride per minute is forced? The coil is under a gage pressure of 64 lb per square inch and the liquid refrigerant is completely vaporized in passing through the coil. Solution. Find that the absolute pressure is 64 plus 14.7 or 78.7 lb per square inch. From Table 3 note that the saturation temperature at this pressure is 75 F (nearly) and that the heat content per pound of the vapor is 207.8 Btu. Also that the heat content of the liquid is 42.2 Btu per pound. Subtract 42.2 from 207.8 and 165.6 Btu per pound is the heat necessary to change the liquid refrigerant to a vapor (latent heat). As the heat to accomplish this change comes from the air around the coil, the heat removed from the air is 165.6 Btu per pound of methyl chloride evaporated in the coil. When the refrigerant is circulated at 2 lb per minute, 2 X 165.6, or 331.2 Btu per minute are removed from the air, or refrigerating effect is produced at the rate of 331.2 -r 200, or 1.65 tons. . AIR DRYINC AGENTS Moisture may be removed from air, thus accomplishing dehumidi fication, by the use of any one of a number of substances if the moist air 36 CHAPTER 2. REFRICERANTS AND AIR DRYING AGENTS and these substances are brought together under suitable circumstances. One class of these substances are solids at ordinary conditions and have the power of adsorbing the moisture from the air. Another class of air drying agents are liquids under ordinary conditions and absorb the mois ture from the air.. Nearly all the drying agents in frequent commercial use in air conditioning installations are of one or the other of these two classes. Adsorbents These substances are characterized by a physical structure containing a great number of extremely small pores but still retaining sufficient mechanical strength to resist whatever wear and handling to which they are subjected. To be suitable for air drying purposes they must be widely available at economical cost, durable in use, stable in form and properties, and capable of withstanding the re-activation processes by which they are made ready for repeated use. They must also possess capacity for adsorbing and holding so sufficient a quantity of moisture that _ the dimensions of the beds necessary to a.ccommodate them will be practical. Aluminum Oxide, (Alumina), in a porous, amorphous form is a solid adsorbent frequendy called by the common name activated alumina, and containing small amounts of hydrated aluminum oxide, and very, small amounts of soda, and various metallic oxides. A good grade of activated alumina will show 92 per cent of AkO3, and its soda content will be com bined with silica and alumina into an insoluble compound. This substance also has the property of adsorbing certain gases and certain vapors other than water vapor--a property which is sometimes useful in air condi tioning installations. It is available commercially in granules ranging from a fine powder to pieces approximately 1.5 in. in diameter. It has Table 6. Properties op Water Temp. F Lb peb Sq In. liquid Vapor Heat Contest and Entbopt Taken Fbom -f32 F Heat Content Entropy . 50 F Superheat 100 F Superheat liquid Vapor liquid Vapor HL Ct Entropy Ht. Ct. Entropy 32 0.0887 0.01602 3296.0 0.00 1073.0 0.0000 2.1826 1096.9 2.2277 1120.8 2.2688 35 0.1000 0.01602 2941.0 3.02 1074.4 0.0062 2.1724 1098.3 2.2172 1122.2 2.2581 40 0.1217 0.01602 2441.0 8.05 1076.8 0.0163 2.1555 1100.6 2.2000 1124.5 2.2406 45 0.1475 0.01602 2034.0 13.07 1079.2 0.0262 2.1390 1102.9 2.1832 1126.7 2.2234 50 0.1780 0.01602 1702.0 18.08 1081.5 0.0361 2.1230 1105.2 2.1667 1129.0 2.2066 55 0.2140 0.01603 1430.0 23.08 1083.9 0.0459 2.1073 1107.5 2.1506 1131.3 2.1902 60 0.2561 0.01603 1206.0 28.08 1086.2 0.0556 2.0920 1109.8 2.1349 1133.5 2.1742 65 0.3054 0.01604 1021.0 33.08 1088.6 0.0652 2.0771 1112.2 2.1196 1135.8 2.1585 70 0.3628 0.01605 868.0 38.07 1090.9 0.0746 2.0625 1114.5 2.1046 1138.1 2.1432 75 0.4295 0.01606 740.0 43.06 1093.2 0.0840 2.0483 1116.7 2.0900 1140.3 2.1283 80 0.507 0.01607 632.9 48.05 1095.5 0.0933 2.0344 1119.0 2.0758 1142.5 2.1138 85 0.596 0.01609 543.3 53.04 1097.8 0.1025 2.0208 1121.2 210619 1144.7 2.0996 90 0.698 0.01610 467.9 58.03 1100.0 0.1116 2.0075 1123.4 2.0483 1146.8 2.0857 95 0.815 0.01612 404.2 63.01 1102.3 0.1206 1.9946 1125.6 2.0350 1148.9 2.0721 100 0.949 0.01613 350.3 68.00 1104.6 0.1296 1.9819 1127.9 2.0220 1151.1 2.0588 105 1.101 0.01615 304.4 72.98 1106.8 0.1384 1.9695 1130.2 2.0093 1153.2 2.0458 For properties of steam at high temperatures, see Page 27. 37 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 high adsorptive capacity per unit of weight, and is non-toxic. It may be repeatedly re-activated after becoming.saturated with adsorbed moisture without practical loss of its adsorptive ability. In the grade frequently used for air drying the re-activation may be accomplished at temperatures under 350 P. Specific gravity is-3.25 and the pores are reported to occupy 58 per cent of the volume of each particle. For most estimating purposes the volume-weight relation on a dry basis may be taken as 50 lb per cubic foot although in the smaller sizes the packed weight may be as much as 64 lb per cubic foot. Silicon Dioxide, (Silica), in a special form obtained by suitably mixing sulphuric acid with sodium silicate, is another solid adsorbent and is commonly called silica gel. Its capillary structure is exceedingly small, so small that its exact structure has to be deduced rather than observed. The gel is available commercially in a wide variety of sizes of granules ranging from 4 to 300 mesh. It has high adsorptive capacity per unit of weight and is non-toxic, may be repeatedly re-activated without practical deterioration. Re-activation may be accomplished at tem peratures of air up to 600 F although it is frequently accomplished with air or other gases at temperatures not over 350 F. Volume of the capillary pores is reported to be from 50 to 70 per cent of the total solid volume. For most estimating purposes the volume-weight relation can be assumed as from 38 to 40 lb per cubic foot on a dry basis; Other substances having properties which make them available as solid adsorbents include lamisilate and charcoal but details of their physical properties are not available. Nature of Adsorption Process ' Adsorption is accomplished, without chemical change between the air and the adsorbent substance. The adsorbent does not go into solution but water vapor is extracted from the air-vapor stream passing through the bed of adsorbent material and is caught and retained in the capillary pores. The exact nature of the process which goes on during adsorption is not known but it is stated that the action is brought about by surface condensation, and also by a difference between the vapor pressure of the water condensing inside the pores and the partial pressure of the water vapor in the air-vapor mixture. The adsorbing process in the bed can continue until the vapor pressures come into equilibrium. The amount of vapor adsorbed will depend on the adsorbent substances being used but for any single substance the amount depends on the temperature of the bed as well as on the partial pressure of the air-vapor mixture being passed over it. .. . As the process of adsorption goes on heat is liberated in the bed. The heat so liberated is the latent heat of the water vapor condensed together with the so-called heat of wetting. For a pound of water vapor at 60 F the latent heat released by condensation is approximately 1057 Btu. The heat of wetting for silica gel, for example, is about 200 Btu, making a total heat of adsorption of approximately 1257 Btu per pound of water adsorbed from the air-vapor mixture passing through the silica gel bed. The heat of wetting varies with the substance being used as the adsorbent while the latent heat of condensation depends only on the temperature and pressure of the water vapor. 38 CHAPTER 2. REFRIGERANTS AND AIR DRYING ACENTS Temperature-Pressure-Concentration Relations Since the adsorptive ability of an adsorbent depends on the temperature of the bed and on the partial pressure difference between the pores and the air-vapor mixture it is important to know the pressures and temperatures at which pressure equilibrium is reached. Evidently the equilibrium conditions represent the limits beyond which adsorption. of vapor cannot continue. The relationship can be Fig. 1. Temperature--Vapor Pressure--Concentration Relation for a Silica Gel Bed at Constant Temperature shown graphically and Fig. 1 is such a chart for silica gel. Charts of like nature can be plotted for other adsorbent materials. Fig. 1 shows the equilibrium conditions for a gel bed maintained at constant temperature while the water vapor adsorption is allowed to continue until pressure equilibrium is reached. Each curve on the chart shows a certain dew-point temperature, and therefore a certain pressure, of the saturated,water vapor. As an example in the interpretation of the chart consider the case when 39 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 moist air at a temperature of.80 F and a partial vapor pressure of.0.5.in. of mercury flows through a bed of silica gel which is at a temperature of 80 F. The chart indicates that the equilibrium of pressure between the air-vapor, mixture and. the'bed is reached when the dry bed has adsorbed moisture to the extent of 31 per cent of the weight,when dry. When this happens the bed.can adsorb no more moisture unless its temperature is changed. . . . .. In practice however the adsorbent bed is seldom held'at a steady'tem perature in air conditioning applications and neither is the adsorption process permitted to continue until moisture equilibrium is reached. Instead, the bed temperature varies and the bed is re-activated before equilibrium is approached. While charts of this kind can show the limiting properties of the substances they are seldom directly applicable Table 7. Dew-Point of Air in Equilibrium with Lithium Chloride Solutions Concentration in Pound Mols (42.4 lb) Lithium Chloride per 1000 lb Water Dew Point at Concentration or Lithium Chloride Conc 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0 26.0 28.0 30.0 320 315.2 308.7 299.9 290.2 279.7 269.4 259.6 251.5 244.1 236.5 230.0 223.8 218.6 214.5 210.3 300295.4 289.1 280.5 270.9 260.6 250.5 240.8 232.6 225.4 218.0211.8 205.8 200.8 196.9 192.8 280275.6 269.5 261.1 251.7 241.5 231.6 222.2 214.0 206.7 199.7 193.5 187.8 183.2 179-3 175.2 260255.8 250.0 241.9 232.6 222.7 212.8 203.5 195.5 188.4 181.7 175.4 170.0 165.6 162.0 158.4 240236.0 230.4222.5 213.5 203.8 194.2 185.0 177.1 170.0 163.6 157.5 152.2 148.3 144.6 140.5 220216.2 210.8203.2 194.4 184.9 175.5 166.4 158.6 151.6 145.3 139.6 134.6 130.7 127-3 124.2 200196.4 191.2183.9 175.4 166.1 156.7 148.0 140.3 133.5 127.3 121.9 117.0 113.3 110.1 180176.6 171.6164.7 156.4 147.3 138.1 129.6 122.1 115.5 109.4 104.2 99.6 96.0 160.156.8 152.1 145.4 137.4 128.6 119.7 111.3 103.9 97.4 91.6 86.6 82.2 140137.0 132.6126.1 118.4 109.9 101.3 93.1 85.9 79.5 73.8 69.0 120117.2 113.0 106.8 99.4 91.1 82.7 74.7 67.8 61.5 56.0 110,107.3 103.2 97.2 89.9 81.9 73.5 65.6 58.8 52.6 47.1 100, 97.4 93.4 87.5 80.5 72.7 64.4 56.6 49.8 43.7 38.2 9C 87.5 83.6 77.9 71.C 63.3 55.2 47.6 40.8 34.8 29.3 80] 77.6 73.8 68.4 61.6 54.C 46.1 38.5 31.8 25.9 20.6 70 67.7 64.0 58.7 52.2 44.8 37.0 29.5 22.9 17.2 12.0 60 57.8 54.3 49.1 42.7 35.5 27.9 20.5 14.0 8.3 4C 38.0 34.7 29.9 23.9 16.9 9.6 2.4 -3.9 2C 15.1 10.7 5.0 -1.7 -8.7 -15.4 0 -4.5 -8.6 -13.9 -20.2 -27.0 -33.3 to the solution of air conditioning problems unless considerable additional information is available. This takes the form of performance data cover ing the characteristics of the equipment in which the adsorbent bed is .placed. Such performance data are beyond the scope of this chapter. Liquid Absorbents ' Any absorbent substance may be used as an air drying agent if it has a vapor pressure lower than the vapor pressure in the air-vapor mixture from which the moisture is to be removed. Absorbents are character istically water solutions of materials in which , the vapor pressure, is reduced to a suitable level by governing the concentration of the solution. In addition to having a suitable low vapor pressure, a practical absorbent must also be widely available at economical cost, be non-corrosive, 40 CHAPTER 2. REFRIGERANTS AND AIR DRYING AGENTS odorless, non-toxic, chemically inert against any impurities in the air stream, stable over the range of use and especially it must not precipitate out at the lowest temperature to which the apparatus is exposed. It must have low viscosity and be capable of being economically regenerated or concentrated after having been diluted by absorbing moisture. Fig. 2. Temperature--Pressure--Concentrations for Lithium Chloride. Water solutions, or brines, of the chlorides of various inorganic elements such as calcium chloride and lithium chloride are the absorbents most frequently used in connection with air conditioning applications and de tailed attention is confined to these two in this chapter. Nature of Absorption Process ' The application consists of bringing the air-vapor stream into intimate contact with the absorbent, permissably by passing the air stream through 41 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 2. REFRICERANTS AND AIR DRYINC AGENTS Table 8. Density of Lithium Chloride Solutions Concentration Pound Mols . (42.4 lb) hiCl FRB 1Q00 LB Water 0 Teuferatdre Deo F SO 100' 150 200 250 both the absorbent and the moist air stream. For every pound of water absorbed and condensed the heat added to the air stream and the brine combined is obtainable from steam tables. For instance, at 60 F the amount of this heat is about 1057 Btu. In addition to this heat there is involved also the so-called heat of mixing which is frequently considerable. 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 1.090 1.124 1.156 1.188 1.217 1.242 1.045 1.085 1.119 1.150 1.181 1.209 1.235 1.257 1.279 1.037 1.076 1.111 1.143 1.172 1.199 1.225 1.248 1.270 1.291 1.026 1.064 1.100 1.132 1.162 1.188 1.214 1.236 1.259 1.280 1.310 1.317 1.012 1.052 1.087 1.122 1.152 1.178 1.203 1.226 1.248 1.279 1.289 1.307 1.313 1.338 1.142 1.168 1.192 1.215 1.237 1.568 1.278 1.296 1.312 1.327 1.34 1.267 1.286 1.302 1.318 1.33 1.35 32 t a finely divided spray of the brine but more generally by passing the air over a metal surface coil where the liquid absorbent presents a large surface to the air stream. The difference in vapor pressure causes some of the vapor in the air-vapor mixture to migrate into the brine. Here it condenses into liquid water and decreases the concentration of the absor bent. In order that the process be continuous means must be provided for counteracting the diluting effect of the extracted moisture and also for maintaining the temperature of the brine sufficiently low to hold the desired vapor pressure. As the water vapor is added to the absorbent and condenses, it gives up its latent heat of condensation which tends to raise the temperature of Table 9. Viscosity of Lithium Chloride Solutions (millipoise) Concentration in Pound Mole (42.4 lb) per 1000 lb Water ' Temperature-Pressure-Concentration Relations Since the absorption process can continue only as long as there is a difference in vapor pressure between the absorbent and the air-vapor mixture and since at a given temperature of the absorbent the vapor pressure depends on the concentration of the solution, evidently there must be a relation between these quantities which if known would state the limits of the process. The relationship would also depend on the absorbent being used, and would have to be determined for each substance Table 10. Properties of Lithium Chloride Solutions Concentration Pound Mom (42.4 lb) IACIper 1000 LB Water Partial Heat or Mixing at 0 F BT(J per lb Temperature Coep. or Partial Hsat or, Mixing BTU per LB PER F Specific Heat at 70 F Boiling Point F Freezing (at 760 MM Point Hg.) Substance that First Sbpabatkb Out on , Freezing 0 0.0 2 2.04 4 7.24 6 16.7 8 31.9 10 51.1 12 . 75.7 14 90.8 16 124.8 18 145 . 20 162 22 . 171 24 177 26 182 28 191 30 194 32 198 0.0 -0.014 -0.036 -0.069 -0.109 -0.143 -0.160 -0.167 -0.176 -0.186 -0.194 -0.20 -0.20 -0.21 -0.21 -0.21 -0.22 . 0.998 0.901 0.831 0.778 0.739 0.710 0.687 0.666 0.647 0.631 0.617 0.604 0.59 0.58 0.575 0.57 0.56 212.0 215.8 221.5 228.9 238.1 248.4 258.8 268.9 277.9 285.8 293.2 300.2 307 313 318 323 328 32 16.3 -5.8 -34.2 -69 .. -90 -40 1 36.5 58.1 86.4 133 156 180 190 195 280 Ice Ice Ice Ice Ice Ice LiCUiH-P UO-8H-P LiCl-2H-) UCI-2HtO LiCl-IW LiCl-HtO LiCl-IW LiCi-H/) LiCl-H-P LiCl-HjO UCl Dbg F 02468 10 12 14 16 18 : 20 22 24 0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 56.75 72.44 97.05 136.8 199.5 28.91 37.07 47.42 63.09 15.45 19.91 25.53 32.58 43.05 11.02 14.26 18.37 23.55 30.90 8.61 11.19 14.42 18.62 24.32 6.82 8.89 11.48 14.94 19.36 5.60 7.31 9.51 12.30 15.92 4.70 6.15 8.07 10.42 13.43 4.01 5.25 6.92 8.93 11.51 3.48 4.56 6.01 7.78 10.00 3.05 4.01 5:28 6.86 8.79 2.72 3.58 4.72 6.14 7.83 2.43 3.21 4.25 5.50 7.02 2.19 2.90 3:84 4.94 6.46 2.00 2.66 332 4.51 5.75 1.86 2.48 3.28 4.17 5.32 T.74 232 3.08 3.89 4.94 84.94 123.3 178.6 58.48 81.10 116.1 165.6 41.40 56.62 79.80 111.2 156.3 32.28 43.45 60.26 82.04 113.8 2539 33.96 46.13 61.52 84.72 20.99 27.67 36.64 48.31 65.77 17.66 22.96 30.06 38.99 52.48 15.00 1936 25.06 32.14 42.76 12.91 16.56 21.28 27.10 35.48 11.22 14.32 18.28 23.12 29.92 9.93 12.59 16.00 20.14 25.64 8.83 11.12 14.09 17.62 22.18 7.91 9.91 12.47 15.50 19.36 7.19 8.97 11.27 14.00 17.22 6.67 8.28 10.38 12.82 15.70 6.19 7.73 9.64 11.86 14:45 1183 89.95 71.12 95.94 56.89 75.86 46.45 60.67 38.55 50.70 32.96 43.05 2831 36.98 24.60 31.92 21.78 28.05 19.68 25.12 18.03 22.80 106.2 84.33 67.92 56.49 47.42 40.55 35.56: 31.92 29.11 used as an absorbent. Fig. 2 shows this relationship graphically for lithium chloride. It will be noted that this chart is essentially similar to that shown in Fig. 1 and its direct usefulness is limited by much the same considerations. In order to permit numerical calculations of air conditioning problems it is desirable to have tables for use instead of a chart like Fig. 2, and Tables 7, 8, 9 and 10 can be used in making calculations for lithium chloride. Instead of tabulating the vapor pressure of the solution of lithium chloride it is preferable to tabulate the dew-point of air in equilibrium with lithium chloride, since it is easy to interpolate between values of the dew-point and not so easy to interpolate accurately between values of vapor pressure. The values for dew-point may be converted to vapor pressures, relative humidity, and wet-bulb of air in equilibrium by means' of the usual psychrometric chart or formula. 43 42 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 In Tables 7, 8, 9 and 10 the unit of concentration is the mol. A M molal solution is defined as a solution containing M X 42.37 grains of anhydrous lithium chloride per 1000 grains of water. The formula con necting concentration in mols with weight in per cent is equivalent to: [100 X M X 42.37] -4- [1000 + (M X 42.37)]. Example 4- Calculate the dew-point, wet-bulb, relative humidity and absolute humidity of air in equilibrium at 100 F with pure lithium chloride solution of density 1.270. Solution. From Table 8 the concentration of a solution of density 1.270 at 100 F is 18.0 M. From Table 7 the dew-point of 18 M lithium chloride at 100 F is 43.7 F. From Table 6, Chapter 1, the partial pressure of water over the solution is 0.2858 in. of Hg,, the absolute humidity is 42.00 grains per pound dry air, and the wet-bulb is 65.8 F. The relative humidity is 14.0 per cent. Example 6. Calculate the boiling point, and freezing point of 18 M lithium chloride solutions. Solution. From Table 10, boiling point (standard) is 285.8 F, freezing point is 58.1 F. The salt precipitated on cooling to this temperature has the composition LiCl-2HjO. Example 6. Calculate the heat of vaporization of 1 lb of water from a !arge_amount of lithium chloride solution at the boiling point. Solution. The heat of boiling is equal to the heat of mixing plus the heat of boiling pure water at the same temperature. The heat of mixing from Table 10 at 18 M and 285.8 F is (145 -- 0.186 X 285.8) = 92 Btu per pound. The heat of vaporization of water from steam tables at 285.8 F is 920 Btu per pound. Therefore the heat of vapori- . zation of water from the solution is 920 + 92 = 1012 Btu per pound. Example 7. One thousand pounds of air per minute at 100 F dry-bulb with a dew point of 70 F and a relative humidity of 39 per cent is passed over 18 M lithium chloride solution. The rate of flow of the solution is 200 gpm and the entering temperature is 80 F. The air leaves the absorber at 85 F dry-bulb and dew-point of 35 F. Calculate (a) the heat to be removed from the lithium chloride solution to maintain these con ditions, and (6) the temperature rise of the solution in passing through the absorber. Solution, (a) The heat content of the entering air: From Table 6, Chapter 1, weight of vapor at 70 F dew-point is 0.01574 lb times heat content of steam at 100 F dry-bulb is 1104.2 (Table 8, Chapter 1) equals 17.41 Btu per pound plus heat content of dry air at 100 F is 24.0 (Table 6, Chapter 1) resulting in heat content of mixture as 41.41 Btu per pound. Similarly, the heat content of the leaving air: Weight of vapor at 35 F dew-point is 0.004262 X 1097.5 = 4.68 Btu per pound plus heat content of dry air at 85 F is 20.39 resulting in heat content of mixture as 25.07 Btu per pound. Heat to be extracted from air is 1000 X (41.41 -- 25.07) = 16.340 Btu per minute. Add to this the heat of mixing of 18M lithium chloride at 80 F equals 145 -- (0.186 X 80) = 130 Btu per pound (Table 10) or for 1000 lb of air X (0.01574 -- 0.00426) X 130 = 1494 Btu per minute. Heat to be removed from solution is 16.340 + 1494 = 17,834 Btu per minute. . (b)The weight of solution circulated is 200 X 1.275 (Table 8) X 8.33 = 2124 lb per minute. Its heat capacity is 2124 X 0.631 (Table 10) = 1340 Btu per minute per degree Fahrenheit. The temperature rise is 17,834 4- 1340 = 13.31 F. ' .44 Chapter 3 PHYSICAL AND PHYSIOLOGICAL PRINCIPLES Chemical Vitiation of Air, Physical Impurities in Air, Thermal Changes Between the Body and Its Environment, Adaptation to Hot Conditions, Adaptation to Cold Conditions, Relation of Air Conditioning Needs to Metabolism, Acclimatization, Effective Temperature Index, Physiological Objectives of Heating and Ventilation, Relation of Air and Wall Tempera tures, Influence of Humidity, Influence of Air Movement, The Four Vital Factors VENTILATION is defined in part as the process of supplying or removing air by natural or mechanical means to or from any space. (see Chapter 46). The word in itself implies quantity but not necessarily quality. From the standpoint of comfort and health, however, the problem is now considered to be one of securing air of the proper quality rather than of supplying a given quantity. The term air conditioning in its broadest sense implies control of any or all of the physical or chemical qualities of the air. More particularly, it is often used to include the simultaneous control of temperature, hu midity, movement and quality of air. The term is broad enough to embrace whatever factors may be found desirable, in a given case, for maintaining the atmosphere of occupied spaces at a condition best suited to the physiological requirements of the human body. CHEMICAL VITIATION OF AIR Under the artificial conditions of indoor life, the air undergoes certain physical and chemical changes which are brought about by the occupants themselves. The oxygen content is somewhat reduced, and the carbon dioxide slightly increased by the respiratory processes. Organic matter, which is usually perceived as odors, comes from the nose, mouth, skin and clothing. The temperature of the air is increased by the metabolic processes, and the humidity raised by the moisture emitted from the skin and lungs. Contrary to old theories, the usual changes in oxygen and carbon dioxide are of no physiological concern because they are too small to produce appreciable effects even under the worst conditions of normal human occupancy. The amount of carbon dioxide in air is often used in ventilation work as an index of odors of human origin, but the information it affords rarely justifies'the labor involved in making the observation1,1. ^.S.H.V.E. Research Report No. 959--Indices of Air Change and Air Distribution, by F. C. Houghten and J. h. Blackshaw (A.S.H.V.B. Transactions, VoL 39, 1933, p. 261). 2A.S.H.V.E. Research Report No. 1031--Ventilation Requirements, by C. P. Yaglou, E. C. Riley and D. J. Coggins (A.S.H.V.E. Transactions, Vol. 42, 1936, p. 133). 45 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Little is known of the identity and physiological effects of the organic matter given off in the process of respiration. The former belief that the discomfort experienced in confined spaces was due to some toxic volatile matter in the expired air is now limited, in the light of numerous re searches, to the much less dogmatic view that the presence of such a substance has not been demonstrated. The only certain fact is that expired and transpired air may be odorous and offensive, and it is capable of producing loss of appetite and a disinclination for physical activity. These reasons, whether esthetic or physiological, call for the introduction of a certain minimum amount of clean outdoor air to dilute the odoriferous matter to a concentration which is not objectionable. In certain industrial processes toxic fumes and gases may be produced, whose removal by local exhaust ventilation is essential for the protection of human health; and in the ordinary occupied space chemical impurities may be contributed by the fumes from certain types of cooking and heating appliances. Odors of cooking should be minimized since it has been shown that odors have an important indirect effect on health in diminishing the appetite for food; and carbon monoxide from imperfect combustion may be a serious hazard to life and health. ' When the only source of contamination is the human occupant, the minimum quantity of outdoor air needed appears to be that necessary to remove objectionable body odors, or tobacco smoke. The concen tration of body odor in a room, in turn, depends upon a number of factors, including socio-economic status of occupants, outdoor air supply, air space allowed per person, odor adsorbing capacity of air conditioning processes, temperature, and other factors of secondary importance. With any given group of occupants and type of air conditioner the intensity of body odor perceived upon entering a room from relatively clean air has been found to vary inversely with the logarithm of outdoor air supply and the logarithm of the air space allowed per person. The minimum outdoor air Supply necessary to remove objectionable body odors under various conditions, as determined experimentally at the Harvard School of Public Health*, is given in Table 1. Outdoor air requirements for the removal of objectionable tobacco smoke odors have yet to be determined. Practical values in the field vary from 10 to 15 cfm per person; this air quantity may and should be a part of that necessary for other-requirements, e.g., removal of body odors,, heat, moisture, etc. , The total quantity of air to be circulated through an enclosure is governed largely by the needs for controlling temperature and air distri bution when either heating or cooling is required. The factors which determine total air quantity include the type and nature of the building, locality, climate, height of rooms, floor area, window area, extent of 'occupancy, and last but not least, the method of distribution. : It will be noted that, with adequate air space, the rate of air change indicated in Table 1 is from 10 to 30 cfm per person. In rooms occupied by only a few persons such a rate of air change will be automatically attained in cold weather by normal leakage around doors and windows while it can easily be secured in warm weather by the opening of windows, With a space allotment of 400 cu ft per person, only 1air changes per CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES hour are necessary to provide an air change of 10 cfm per person. This space allotment is essential for other reasons. It is indicated by the space requirements of ordinary furniture with room to move about between, and it is about the space needed in a two-bed sleeping room to avoid mouth spray infection. . . Therefore, in the ordinary dwelling with adequate cubic space allot ment, no special provision for controlling chemical purity of the air is necessary (aside from removal of fumes from heating appliances). With such conditions, the control of heat loss from- the body is the major Table 1. Minimum Outdoor Air Requirements to Remove Objectionable Body Odors (Provisional values subject to revision upon completion of work) Am Space pee Person Cu Ft Outdoor Am Supply. CFM feb Person Healing season with or without recirculation. Air not conditioned. Sedentary adults of average socio-economic status.__ Sedentary adults of average socio-economic status.__. Sedentary adults of average socio-economic status.__ Sedentary adults of average socio-economic status.__ Laborers.......................................... Grade school children of average class Grade school children of average class Grade school children of average Hass Grade school children of average class Grade school children of Door class ' Grade school children of better class Grade school children of best class 100 200 300 500 200 100 200 300 500 200 200 100 . 25 16 . ' 12 7 29 21 17 H 38 . 18 22 Heating season. Air humidified by means of centrifugal humidifier. Water atomization rate 8 to 10 gph.- . Total air circulation SO cfm per person. Sedentary Adults.. 200 12 Summer season. Air cooled and dehumidified by means of a spray dehumidifier Spray water changed daily. Total air circulation SO cfm per person. Sedentary Adults.. . 200 <4 factor to be considered. The air breathed in the dwelling rarely contains chemical impurities; but the air which bathes the skin may often be too hot or too cold. .\ . In more crowded rooms (large offices, large workrooms, auditoriums); the whole picture changes. Cubic space per person is less arid the size of the room makes it impossible to admit untempered outside air without drafts. Here, mechanical ventilation is essentialybut as will -be noted in a later paragraph, it is even more essential, for thermal than for chemical reasons. It is the removal of the heat produced by human bodies, rathef than dilution of chemical poisons, which must govern practice. . 47 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 In spite of the rapid advances in the field of air conditioning during the past few years, the secret of reproducing indoor atmospheres of as stimulating qualities as those existing outdoors under ideal weather conditions, has not as yet been found. Extensive studies have failed to elucidate the cause of the stimulating qualities of country air, qualities which are lost when such air is brought indoors and particularly when it is handled by mechanical means. Ultra-violet light and ionization have been suggested but the evidence so far is inconclusive or negative4. Ozone has been used with success for the destruction of micro-organisms (molds) in meat packing establishments and the like; and where con siderable amounts of organic effluvia are present this substance may be useful as a deodorant. For ordinary ventilation practice, however, neither of these purposes can be usefully attained, since the concentration of ozone necessary for effectiveness would be likely to transcend the limit of comfort in ordinary occupied rooms. While ozone has been used in the treatment of certain diseases, there is no evidence that it has a tendency to increase comfort or to benefit health under conditions of normal human occupancy. The allowable concentrations in the breathing zone are very small, between 0.01 to 0.05 ppm parts of air. These are much too small to influence bacteria. Higher concentrations are associated with a pungent unpleasant odor and considerable discomfort to the occupants. One part per million causes respiratory discomfort in man, headaches and depression, lowers the metabolism, and may even lead to coma5. PHYSICAL IMPURITIES IN AIR Dust particles of various types, when present in considerable con centrations, produce an irritant effect upon the mucous membranes of nose and throat and may be associated with high prevalence of acute respiratory diseases such as bronchitis and pneumonia. Dust which contains free silica has special harmful effects, causing a primary disease of the lungs (silicosis) and predisposing the victim in a high degree to tuberculosis. These, however, are special problems of industrial hygiene which will not be discussed in detail in this chapter. A certain part of the dissemination of disease in confined spaces is caused by the emission of pathogenic organisms from infected persons. Droplets sprayed into the air in talking, coughing, sneezing, etc., do not all fall immediately to the ground within a few feet from the source, as was formerly believed. The large droplets.do, of course, but minute droplets less than 0.1 mm in diameter evaporate to dryness before they fall the height of a man. Nuclear residues from such sources, which may contain `A.S.H.V.E. Research Report No. 921--Changes in Ionic Content in Occupied Rooms, Ventilated by Natural and Mechanical Methods, by C. P. Yaglou, L. C. Benjamin and S. P. Choate (A.S.H.V.E. Trans actions, Vol. 38.1932, p. 191). A.S.H.V.E. Research Report No. 965--Physiologic Changes During Ex posure to Ionued Air, by C. P. Yaglou, A. D. Brandt and L. C. Benjamin (A.S.H.V.E. Transactions. VoL 39,1933, p.357). A.S.H.V.E. Research Report No. 985--Diurnal and Seasonal Variations in the Small Ion Content of Outdoor and Indoor Air, by C. P. Yaglou and L. C. Benjamin (A.S.H.V.E. Transactions, Vol. 40. 1934, p. 271). The Nature of Ions in Air and Their Possible Physiological Effects, by L. B. Loeb (A.S.H.V.E. Transactions, Vol. 41,1935, p. 101).. The Influence of Ionized Air upon Normal Subjects, by L. P. Herrington {Journal Clinical Investigation, 14, January, 1935). The Effect of High Concentrations of Light Negative Atmospheric Ions on the Growth and Activity of the Albino Rat, by L. P. Herrington and Karl L. Smith {Journal Ind. Hygiene, 17. November, 1935). Subjective Reactions of Human Bangs to Certain Outdoor Atmospheric Conditions, -by C.-E. A. Winslow and L. P. Herrington (A.S.H.V.E. Transactions. Vol. 42, 1936. p. 119).. . *Tke British Medical Journal, Editorial, June 25, 1932, p. 1182. See also Loc. Cit. Note 4. . 48 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES infective organisms drift long distances with the air currents and the virus may remain alive long enough to be transmitted to other persons in the same room or building. Droplet nuclei have been recovered from cultures of resistant micro-organisms a week after innoculation into a tight chamber of 3000 cu ft capacity, although the majority of disease germs died out within a few hours5. Practical epidemiological evidence indicates that the danger of such atmospheric transmission is slight with the bacterial diseases but may be appreciable with the diseases caused by the much smaller and lighter viruses. Avoidance of overcrowding is a major factor in avoiding such dangers. The microbic content of the atmosphere may also be reduced by air change but local drafts carrying minute droplets from person to person will increase the hazard.' Practical possibilities in sterilizing air supplies by the use of ultra-violet light are now being studied7. - THERMAL INTERCHANGES BETWEEN THE BODY AND ITS ENVIRONMENT The importance of the thermal factors arises from the profound influence which they exert upon body temperature, comfort and health. Body temperature depends upon the balance between heat production and heat loss. The heat resulting from the combustion of food within the body (metabolism) maintains the body temperature well above that of the surrounding air. At the same time, heat is constantly lost from the body by radiation, conduction and evaporation. Since, under ordinary conditions, the body temperature is maintained at its normal level of about 98.6 F, the heat production must be balanced by the heat loss. In conditioning air for comfort and health it is necessary to know the rate of sensible and latent heat liberation from the human body, which in conjunction with other heat loads (see Chapters 5, 7 and 8) determine the capacity required for proper conditioning. The data in common use are those of the A.S.H.V.E. Research Laboratory8. The fundamental thermodynamic processes concerned in heat inter changes between the body, and its environment may be described by the equation: ' '' M. 5 = E R C (1) where '. Af = rate of metabolism. 5 = rate of storage. E = rate of evaporative heat loss. R = rate of radiative heat loss or gain. C = rate of convective heat loss or gain. . . Units may be expressed in kilogram-calories or Btu per hour, and storage is considered positive when the body cools; negative, when the flAir-Borne Infection and Sanitary Air Control, by W.- F. Wells {Journal Industrial Hygiene, November, 1935). - 'Sanitary Ventilation in Wards, by W. F. Wells (Heating and Ventilating, April. 1939, p. 26). Measure ment of Sanitary Ventilation, by W. F. Wells {American Journal of Public Health, Vol. 28, 1938,. p. 343). (Thermal Exchanges Between the Bodies of Men Working and the Atmospheric Environment, by F. C. Houghten. W. W. Teague, W. E. Miller, and W. P. Yaint {American Journal of Hygiene, Vol. XIII No. 2. March, 1931, p. 415). . 49 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 body becomes warmer. M is always positive, and E is always negative. R and C are positive when the surface of the body is above that of walls and air, respectively, and negative when the surface of the body is cooler than walls or air. The human body possesses remarkable powers of adaptation to a range of atmospheric conditions around an ideal optimum where storage is zero, and metabolism and skin and tissue temperature are at optimum values. As skin temperature and body-tissue temperature rise or fall above or below an optimum, complex adaptive mechanisms come into play, chiefly associated with redistribution of blood supply between the skin and deeper tissues (in a cold environment) and with sweat secretion (in a hot environment). Under cold conditions, shivering or other muscular move ments increase metabolism, which is, again, a reaction favorable to tem perature regulation; but under very hot conditions metabolism also rises and this reaction is obviously harmful and indicates failure of the entire regulative process. These reactions are governed by nervous or chemical stimuli from both skin and internal tissues. Nerves from the skin, for example, carry the sense impressions to the brain and the response comes back over another set of nerves, the motor nerves, to the musculature and to all the active tissues in the body, including the endocrine glands. In this way, a two-sided mechanism controls the body temperature by (1) regulation of internal heat production (chemical regulation), and (2) regulation of heat loss by means of automatic variation in the rate of cutaneous circulation and the operation of the sweat glands (physical regulation). The mechanisms of adjustment are complex and the re actions involved in a cold and in a hot environment are radically different in nature. Therefore, any attempt to formulate simple engineering relationships covering the entire thermal scale are obviously doomed to failure. In a certain middle range, normal and easy physiological regulation occurs by slight changes in the distribution of blood between the skin and the inner organs; here, heat loss and heat gain balance and a sensation of comfort is experienced. Above this range, the blood capillaries in the skin become dilated, allowing more blood to flow into the skin, and thus increase its temperature and consequently its heat loss. If this method 6f cooling is not in itself sufficient, the stimulus is extended to the sweat glands which allow water to pass through the surface of the skin, where it is evaporated. This method of cooling is the most effective of all, as long as the humidity of the air is sufficiently low to allow for evaporation. In high humidities, where the difference between the dew-point tempera ture of the air and body temperature is not sufficient to allow rapid evaporation, equally good results may be obtained by increasing air movement. The body, under hot conditions, is in the zone of evaporative regulation, and for moderately extreme conditions perfect balance between heat production and heat loss may be attained, although at the cost of considerable discomfort. In a cold environment, where environmental conditions are such as to remove heat too rapidly, the organism adapts in some degree by con stricting the blood vessels of the skin, increasing the insulation of the body. The lowered surface temperature of the skin decreases heat loss which obviously depends on the differential between the temperature of - . ' . , ' 50 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES the skin and of the environment. This adaptation is, however, partial and incomplete, and the temperature of the body tissues falls, with accompanying discomfort and ultimate danger of serious chill. The process, may go oh for many hours. This is known as the zone of body cooling. The normal tendency of - the individual is to move about and increase metabolism through muscular activity and thus balance the excessive heat demand of the environment. .' These phenomena are important and a graph indicating the reactions of lightly-clothed human: subjects in a semi-reclining position is shown in Fig. 1. The air movement was minimal and relative humidity between 40 and 50 per cent. The abscissae are operative temperatures which represent the combined effect of air and wall temperatures9, the ordinates, heat loss per unit of body surface. The following phenomena are obvious: I. Metabolism (for a given subject) remains approximately constant within the range of operative temperatures employed, and rises slightly below 70 F. . . ; . , .,2- At a critical temperature of 85 F the heat produced by metabolism (roughly 50 kilogram-calories per square meter per hour) is balanced by the heat loss due to evapo ration and to radiation plus convection; these two major components accounting for about 25 kilogram-calories each. Storage is zero; that is, the body tissues show no change in temperature. ." ' ,, A-S .H-V-E. Research Paper--Recent Advances in Physiological Knowledge and Their Bearing on Ventilation Practice, by C.-E. A. Winslow, T. Bedford, E. F. DuBois, R. W. Keeton, A. Miiaenard E E 193|rep 54) C' Tasker iA S H V E- JOURNAL Section, Heating, Piping and Air Conditioning, January.1 51 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 3. As one proceeds to higher operative temperatures, the heat received from the environment due to radiation plus convection increases progressively but is exactly balanced by a similarly progressive increase in evaporative heat loss, so that no further negative storage (warming of the body) takes place. At an operative temperature of 100 F the body is gaining 10 kilogram-calories from the combined influence of walls and air, and this heat gain plus the metabolic heat produced is balanced by a heat loss of 60 kilogram-calories due to evaporation. 4. Below the critical temperature of 85 F the phenomena are wholly different. Evaporative heat loss here changes but slightly, falling from 20 to 10 kilogram-calories per hour as the operative temperature decreases, as a result chiefly of the purely physical factor of decreasing vapor pressure difference between skin and air. In this zone, heat loss due to the combined influence of radiation plus convection increases progressively (although the slope of the line is less rapid than above 85 F). Since this progressively increasing heat loss is not balanced, there is a parallel increase in storage (cooling of the body tissues). Fig. 2. Contour Chart Indicating Limiting Wetted Areas Associated with Certain Sensations of Pleasantness (in the Zone of Evaporative Regulation) in Relation to Air Temperature and Relative Humidity. Observed Mean Comfort Votes are Indicated in Each Region. (Unclothed Subjects.) Localized drafts are important since differential cooling of one area of the body may produce surprisingly unpleasant reactions in quite different parts of the body. In a recent experiment10 it was shown that the appli cation of an ice pack to an area of 60 sq cm on the back of the neck for 15 min caused a drop of 17 F in the skin temperature of the fingers and that this low temperature of the fingers persisted for one hour after the ice pack was removed. "The Relative Influence of Radiation and Convection Upon the Temperature Regulation of the Clothed Body, by C.-E. A. Winslow, L. P. Herrington, and A. P. Gagge (American Journal of Physiology, VoL 124, October, 1938, p. 51). 52 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES ADAPTATION TO HOT CONDITIONS - Within a certain thermal region on the hot side of the optimum, the body can balance increases in air or wall temperature by increasing secretion of sweat. The body can balance changes in relative humidity within this zone j'ust as precisely as it can balance changes in tempera tures, up to the point where the sweat no longer evaporates but runs off without exerting its cooling power. Until the latter point is reached, evaporative heat loss, at a given air temperature, is exactly the same whether humidity be high or low. It is important to note, however, that even in the range where this type of adaptation is thermally adequate, the process of sweat secretion is associated with sensations of marked discomfort. It has been demon strated that welted area, the physiological index of sweat secretion, shows a correlation of 0.65 0.006 with expressions of discomfort11. Further- Table 2. Upper Limits of Evaporative Regulation (Clothed Subject) Environmental Temperature Deg F 126.9 122.0 113.0 108.5 104.5 99.5 95.0 90.5 87.8 Deg C 52.7 50.0 45.0 42.5 40.0 37.5 .35.0 .32.5 31.0 Relative Humidity Per Cent '0 5 18 26 38 51 69 89 100 more, there develops, even under moderate conditions of overheating, a definite disclination for physical activity. The New York State Com mission found that experimental subjects performed 28 per cent less work at 86 F with 80 per cent relative humidity than at 68 F with 50 per cent relative humidity12. The upper limit of this zone of evaporative regulation is,, of course, established by the combination of air and -wall temperature, .relative humidity and air movement beyond which the sweat runs off without evaporation and cooling of the body surface. Limits for. unclothed, semi-reclining subjects, with minimal air movement are shown in Fig. 2. Studies at the John B. Pierce laboratory of Hygiene have.established,the upper limits of evaporative regulation for the clothed, semi-reclining body at an air movement of 17 fpm as shown in Table 213. Since 1922 notable progress has been made by the A.S.H.V.E. Research Laboratory in fixing corresponding upper limits for subjects engaged in u Relations Between Atmospheric Conditions. Physiological Reactions, and Sensations of Pleasantness, by G^E. A. Winslow, L. P. Herrington, and A. P. Gagge (American Journal of Hygiene, Vol. 26, July, 1937, ^Ventilation Report of the New'York State Commission on .Ventilation (E. P. Dutton Co., N. Y., 1923). 13The Reactions of the Clothed Human ..Body to Variations in Atmospheric Humidity, by C.-E. A. Winslow, L. P. Herrington, and A.. P. Gagge (American Journal of Physiology, Vol. 124, December, 1938, p. 692). '' 53 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 active work14, limits which are, of course, much lower than those cited for subjects at rest, The upper limit of effective temperature to which the human organism is capable of adapting itself without serious discomfort or injury to health is 90 deg ET (Effective Temperature) for men at rest and between 80 and 90 deg ET for men at work depending upon the rate of work. Within these limits a new equilibrium is established at a higher body temperature level through a chain of physiological adjustments. The heat regulating center fails when the external temperature is so abnormally high that bodily heat cannot be eliminated as fast as it is produced. Part of it is. retained in the body, causing a rise in skin and deep tissue temperature, an increase in the heart rate, and accelerated respiration. (See Table 3.) In extreme heat the metabolic rate is markedly increased owing to the excessive rise in body temperature16, and a vicious cycle results which may eventually lead to serious physio logic damage. Table 3. Physiological Responses to Heat of Men at Rest and at Works Eptbctite Tehp Actual Chest Temp (Deo Pass) 60 70 80 85 90 95 100 105 110 96.1 96.6 97.0 97.6 99.6 104.7 . Men at Rear Men at Wore 90,000 pt-lb or Wore pbb Hour Rise in Rectal Temp (Deg Fahr per Hour) Increase in Pulse Rate (Beats per Min per Hour) Approximate Leas m Body Wright by Perspiration (Lb per Hr> Total Work Accomplished (Ft-Lb) Rise in Body Temp (Deg Fahr per Hr) Increase in Pulse Rate (Beats per Min per Hr) Approximate Loss in Body Wt by Per spiration (Lb per Hr) 0.0 0.0 0.1 0.3 0.9 2.2 4.0 5.9>> 0 0 i 4 15 40 83 137b 0.2 0.3 0.4 0.5 0.9 1.7 2.7 4.0b 225,000 225,000 209,000 190,000 153,000 . 102,000 67,000 49,000 37,000 0.0 0.1 0.3 0.6 1.2 2.3 4.0 6.0b 8.5b 6 7 11 17 31 61 103b 158b 237b 0.5 0.6 0.8 1.1 1.5 2.0 2.7 3.5b 4.4b ftData by A:S.H.V.E. Research Laboratory. bComputed value from exposures lasting less than one hour. Examples of this are met with in unusually hot summer weather and in hot industries where heat loss from the body, by radiation and convection is impossible. Consequently, the workers depend entirely on evaporation for the elimination of body heat. They stream with perspiration and drink liquids abundantly to replace the loss. One of the deleterious effects of high temperatures is that the blood is diverted from the internal organs to the surface capillaries, in order to serve in the process of cooling! This affects the stomach, heart, lungs and other vital organs, and it is suggested that the feeling of lassitude and discomfort experienced is due in part to the anaemic condition of the brain. The stomach loses some of its power to act upon the food, owing to a diminished secretion of gastric juice, and there is a corresponding loss ua.S.H.V.E. Research Paper--Air Conditioning in Industry, by W. L. Fleisher, A. E. Stacey, Jr.* F. C. Houghten, and M. B. Ferderber (A.S.H.V.E. Journal Section, Healing, Piping and Air Conditioning, February, 1939, p. 107; March, 1939, p. 191; April, 1939, p. 255). ^A.S.H.V.E. Research Report No. 719--Basal Metabolism Before and After Exposure to High Tem peratures and Various Humidities, by W. J. McConnell, C. P. Yaglou and W. B. Fulton (A.S.H.V.E. Transactions, Vol. 31, 1925, p. 123). 54 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES in the antiseptic and antifermentive action which favors the growth of bacteria in the intestinal tract16. These are considered to be the potent factors in the increased susceptibility to gastro-intestinal disorders in hot summer weather. In warm atmospheres, particularly during physical work, a considerable amount of chloride is lost from the system through sweating. The loss of this substance may lead to attacks of cramps, unless the salts are re placed in the drinking water. In order to relieve both cramps and fatigue, it is recommended that 6 g of sodium chloride and 4 g of potassium chlo ride be added to a gallon of water17. The deleterious physiologic effects of high temperatures exert a power ful influence upon physical activity, accidents, sickness and mortality. Both laboratory and field data show clearly that physical work in warm atmospheres is a great effort, and that production falls progressively as the temperature rises. The incidence of industrial accidents reaches a minimum at about 68 F, increasing above and below that temperature. Sickness and mortality rates increase progressively as the temperature rises. The control of hot conditions by chilling the walls of an occupied space has only limited application in practice. Either air-cooling, increase in air movement, or dehumidification, or any combination of these pro cedures may be used in practice to keep such occupied space cool in summer. ADAPTATION TO COLD CONDITIONS When the heat demand of the environment exceeds the metabolic output, the chief changes which occur, as external temperature decreases, are (I) increased heat loss due to radiation plus convection, and (2) in creased positive storage or cooling of the body tissues. It will be noted in Fig. 1 that the slope of the line representing heat loss due to radiation plus convection changes as one passes from the zone of evaporative regu lation to the zone of body cooling. The less abrupt slope in the latter zone is due to a progressive fall in skin temperature which is the only mecha nism the body calls into play in this region to adapt to a cool environment. Under colder conditions, or after longer periods of time, a second mechan ism, increased metabolism, may become operative but this does not appear in the experiments here reviewed. For a fall in operative temperature from 88 to 68 F the mean skin temperature decreases from 94 to 84 F. The temperature of the lower extremities falls most rapidly while that of the head or trunk may decrease less. This type of regulation is, however, as pointed out previously, incomplete; and positive storage (cooling of the body) increases pro gressively as external temperature falls. Chilling, then, imposes an extra load upon the heat-producing organs to maintain body temperature. The strain falls largely upon digestion, metabolism, blood circulation, and the kidneys, and indirectly upon the nervous system18. In extremely `^Influence of Effective Temperature upon Bactericidal Action of Gastro-intestinal Tract, by Arnold and Brody {Proceedings Society Exp. Bid. Med., Vol. 24, 1927, p. 832). .. . Effects of High Air Temperatures Upon the Miner, by K. N. Moss (Transactions Institute of Mining Engineers, Vol. 66, 1924, p. 284). "Preventive Medicine and Hygiene, by M. J. Rosenau (6th Edition, p. 909). 55 HEATING VENTILATING AIR CONDITIONING GUIDE 1940. cold atmospheres compensation, by increased metabolism becomes inade quate. The body temperature falls and the reflex irritability of the spinal cord is markedly affected. The organism may finally pass into an unconscious state which ends in death. A moderate amount of variability in temperature is known to be beneficial to health, comfort, and the performance of physical arid mental work. On the other hand, extreme changes in temperature, such as those experienced by passing from a warm room to the cold air out-of doors, appear to be harmful to the tissues of the nose and throat which are the portals for the entry of respiratory diseases. Experiments show that chilling causes a constriction of the blood vessels of the palate, tonsils, throat, and nasal mucosa, which is accom panied by a fall in the temperature of the tissues. On re-warming, the palate and throat do not always regain their normal temperature and blood supply. This anaemic condition favors bacterial activity and it probably plays a part in favoring infection with common colds and other respiratory diseases. Lowered resistance may also be related to a dimi nution in the number and phagocytic activity of the leucocytes (white blood cells) brought about by exposure to cold and by changes in tem perature. Sickness records in industries seem to strengthen this belief. The Industrial Fatigue Research Board of England19 found that with the workers exposed to high temperatures and to changes in temperature, namely, steel smelters, puddlers, and general laborers, there is an excess of all sickness, the excess among the puddlers being due chiefly to respira tory diseases and rheumatism. The causative factor was not the heat itself but the sudden changes in temperature to which the workers were exposed. The tin-plate millmen who were not exposed to chills, since they work almost continuously throughout the shift, had no excess of rheumatism and respiratory diseases. On the other hand, the blast- . furnacemen, who work mostly in'the open, showed more respiratory sickness than the steel workers. This experience in British factories is well in accord with the findings in American industries20,21. According tp these data the highest pneumonia death rate is associated with dust, extreme heat, exposure to cold, and to sudden changes in temperature. In the ordinary dwelling not equipped with a fan system during the winter season, air movement is likely to be minimal and the only air movements affecting comfort are those due to cold walls or convective heating. Below an air temperature of 77 F, for the clothed, semi-reclining body, sweat secretion is at a minimum and, even with high atmospheric humidity, all the moisture available is evaporated. Under conditions of low air movement, and with a relative humidity of 30-35 per cent, the evaporative heat loss is only 1.5 Btu per square foot , of body surface greater than with a relative humidity of 75-80 per cent. This is the equivalent of decreasing the air temperature by less than 1 F. "Fatigue and Efficiency in the Iron and Steel Industry, by H. M. Vernon {Industrial Fatigue Research Board Report No. 5, 1920, London). Iron Foundry Workers Show Highest Percentage of Deaths from Pneumonia (Statistical Bulletin, Metropolitan Life Insurance Co., New York, N. Y.f 1928). . "The Pneumonia Problem in the Steel Industry, by D. K. Brundage and J. J. Bloomfield CJournal of Industrial Hygiene, 14, December, 1932). -' 56 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES relation of air conditioning needs to metabolism The major objective of heating and ventilation is to balance heat losses from the human body. The basic factor is human metabolism. The desirable environment, from the standpoint of heat loss, depends directly on the heat produced in the body and this heat may be five times as great Table 4. Relation Between Metabolic Rate and Activity Activity Hourly Metabolic Rate tor Ava Person or Total Heat Dissipated, Btu per hour Hourly Hourly Moisture Sensible Latent Dissipated Heat Dis Heat Dis . per Hour sipated, sipated, Btu per Btu per Hour Hour Grains Pounds Basal.......................................... -.................... -........................... 291 Seated at Rest....................................................................... 384 Reading Aloud (Seated). ................................................ 420 Standing at Rest................................................................... 431 Hand Sewing (Seated)...... ............................................... 441 Knitting 23 stitches per minute on Sweater....... 462 Dressing and Undressing. .......................................... 468 Tailor.:......................................... ............................................... 482 Singing............ ............................ ............................................... 486 Office Worker Moderately Active. .......................... 490 Light Work Standing.--.................................................. 549 Typewriting Rapidly. ............................ ................. Ironing with 5 lb iron. ..................................................... 558 570 Dishwashing--Plates, Bowls, Cups and Saucers 600 Clerk Moderately Active Standing at Counter.. 600 Book Binder. ......................................................................... 626 Shoemaker..... .................................................................... 661 Sweeping Bare Floor 38 Strokes per Minute.... 672 Pool Player............................................................................. 680 Walking 2 mph, Light Dancing.............................. 761 Light Metal Worker, (at Bench)................................. 862 Painter of Furniture (at Bench)................................. 876 Carpenter................................................................................ 954 Restaurant Serving.............................................................. 1000 Pulling Weight. .................................................................. 1041 Walking 3 mph... _.......................................................... 1050 Walking 4 mph, Active Dancing, Roller Skating 1390 Walking Down Stairs....... 1...........................................:... 1444 Stone Mason.......... ................................................................. 1490 Bowling. ....... ....................................................... 1.................. . 1500 Man Sawing Wood.................... f..................................... 1800 Swimming.............................................................................. 1986 Running 5.3 mph. -.......................... J.......................... 2268 Walking 5 mph 2330 Walking Very Fast 5.3 mph. _ ........................... 2580 Walking Up Stairs. ....................................................... 4365 Maximum Exertion Different People...................... 3000-4800 145 225 225 225 225 225 225 225 225 225 225 225 225 225 225 225 225. 229 230 250 277 280 307 325 335. 339 452 467 490 490 590 145 159 195 206 216 237 243 257 261 265 324 333 345 375 375 401 436 443 450 511 585 596 647 675 708 711 938 977 1000 1010 1210 979 1070 1316 1390 1458 1600 1640 1740 1762 1790 2187 i2248 2329 2530 2530 2710 2940 2990 3040 3450 3950 4020 4367 4556 4745 4750 6330 6595 6750 6820 8170 0.140 0.153 0.880 0.199 0.208 0.229 0.234 0.248 0.252 0.256 0.312 0.321 0.333 0.362 0.362 0.387 0.420 0.427 0.434 0.493 0.564 0.575 0.624 0.651 0.677 0.679 0.904 0.942 0.964 0.974 1.167 -- when a man is exercising violently as when he is reclining and at rest. Therefore, there is no absolute optimum of air temperature or other environmental conditions, which will meet all cases. With moderate relative humidity and minimum air movement, an air temperature of 80 F has been found ideal for the lightly clothed subject at rest in a semi-reclining position. In factories where light work is performed in summer time, the ideal has been found to be about 76 F. For children 57 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 (who have a high metabolism) at school, in winter clothing, 70 F has been considered correct; while in a gymnasium, 55 F is a desirable temperature. The wide variations in metabolic activity with which we must be pre pared to cope are indicated in Table 4M, and the influence of such vari ations in metabolism upon the heat-load contributed by the human body to the environment is illustrated in Fig. 3. The relation between sensible heat loss and dry-bulb temperature for still air is shown in Fig. 4, and Fig. 5 indicates latent heat and moisture loss in relation to dry-bulb temperature on a similar basis. CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES : Fig. 4. .. Relation Between Sensible Heat Loss from the Human Body and . ' Dry-Bulb Temperature for Still Air3 Fig. 3. Relation Between TotauHeat Loss from the Human Body and Effective Temperature for Still Air Curve A--Men working 66,160 ft-lb per hour. Curve B--Men working 33,075 ft-lb per hour. Curve C--Men working 16,538 ft-lb per hour. Curve D--Men seated at rest. Curves A and C drawn from data at an effective temperature of 70 deg only and extrapolating the relation between curves B and D, which were drawn from data at many temperatures. -' . ACCLIMATIZATION Acclimatization and the factor of psychology are two important influences in air conditioning which cannot be ignored. The first is man's ability to adapt himself to changes in air conditions; the second is an intangible matter of habit and suggestion. Some persons regard the unnecessary endurance of cold as a virtue. They believe that the human organism can adapt itself to a wide range** **Loc. Cit. Note 14. 58 Fig. 5. Latent Heat and Moisture Loss from the Human Body by Evaporation, in Relation to Dry-Bulb Temperature for Still Air Conditions* Curve A--Men working 66,150 ft-lb per hour. Curve B--Men working 33,075 ft-lb per hour. Curve C--Men working 16,538 ft-lb per hour. Curve D--Men seated at rest. Curves A and C drawn from data at a dry-bulb temperature of 81.3 F only and extrapolating the relation between curves B and Z> which were drawn from data at many temperatures. . HEATING VENTILATING AIR CONDITIONING GUIDE 1940 of air conditions with no apparent discomfort or injury to health. In the light of present knowledge of air conditioning these views are not justified. Acclimatization to extreme conditions involves a strain upon the heat regulating system and interferes with the normal physiologic functions of the human body. Thousands of years in the heat of Africa do not seem to have acclimatized the Negro to a temperature averaging 80 F. The same holds true of northern races with respect to cold, although the effects are mitigated by artificial control. An environment averaging 64 F for the 24-hour period is associated with minimal mortality23. Within limits, however, there does occur a definite adaptation to ex ternal temperature level. People and animals raised under conditions of tropical moist heat stand chilling poorly as they are unable quickly to increase internal combustion to keep up the body temperature. For this reason they have trouble standing the cold, stormy weather of the temperate zones, and when exposed to it are very susceptible to respira tory infections. Likewise, people living in cool climates suffer greatly in the moist heat of the tropics until their adaptive mechanism has been, trained. Within a couple of years, however, they find themselves standing the heat much better and disliking the cold. The adaptive level changes somewhat with the season24. There are also marked differences between the sexes. In the cold zone the thickness of the thermal insulating tissues of women is almost double that of men, although the sensory responses to cold are similar. In the hot zone, the threshold of sweating and skin temperature levels ate both higher for women. . Finally, the thickness and insulating value of the clothing worn is an important factor in the determination of the comfort level. EFFECTIVE TEMPERATUREINDEX : Sensations of warmth or cold depend, not only on the temperature of the surrounding air as registered by a dry-bulb thermometer, but also, upon the temperature indicated by a wet-bulb thermometer, upon air, movement and upon radiation effects. Dry air at a relatively high temperature may feel cooler than air of considerably lower temperature with a high moisture content. Air motion makes any moderate condition feel cooler. Radiation from cold or warm surfaces is another important factor under certain conditions. ' Combinations of temperature,, humidity,andair movement which; induce the same feeling of warmth are called thermo-equivalent condi- _ tions. A series of tests25,2^-27,28 at the A.S.H.V.E. Research Laboratory, ' "Civilization and Climate, by Ellsworth Huntington. Yale University Press, 1928. "The Reactions of the Clothed Human Body to Variations in Atmospheric Humidity, by C.-E. A. Winslow, L. P. Herrington and A. P. Gagge (American Journal of Physiology, Vol. 124, December, 1938, ' p. 692). , "A.S.H.V.E. Research Report No. 673--Determination of the Comfort Zone, by F. C. Houghten' and C. P. Yagloglou (A.S.H.V:E. Transactions, Vol. 29, 1923, p. 361). "A.S.H.V.E. Research Report No. 691--Cooling Effect on Human Beings by Various Air Velocities,' by F. C. Houghten and C. P. Yaglou (A.S.H.V.E. Transactions. Vol. 30, 1924. p. 193). * "A.S.H.V.E. Research Report No. 717--Effective Temperature with Clothing, by C. P. Yaglou and' W. E. Miller (A.S.H.V.E. Transactions, Vol. 31, 1925. p. 89). ' "A.S.H.V.E. Research Report No. 755--Effective Temperature for Persons Lightly Clothed and Working in Still Air, by F. C. Houghten, W. W. Teague, and W. E. Miller (A.S.H.V.E. Transactions. VoL 32. 1926. p. 315). 60 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES Fig. 6. A.S.H.V.E. Comfort Chart for Air Velocities of 15 to 25 fpm (Still Air) Note.--Both summer.and winter comfort zones apply to inhabitants of the United States only. Applica tion of winter comfort line is further limited to rooms heated by central station systems of the convection type. The line does not apply to rooms heated by radiant methods. Application of summer comfort line is limited to homes, offices and the like, where the occupants become fully adapted to the artificial air con ditions. The line does not apply to theaters, department stores, and the like where the exposure is less than 3 hours. Pittsburgh, established the equivalent conditions met with in general air conditioning work. This scale of thermo-equivalent conditions not only indicates the sensation of warmth, but also determines the physiological effects on the body induced by heat or cold. For this reason, it is called the effective temperature scale or index. Effective temperature is an empirically determined index of the degree of warmth perceived on exposure to different combinations of tempera ture, humidity, and air movement. It was determined by trained subjects who compared the relative warmth of various air conditions in two ad- 61 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 joining conditioned rooms by passing back and forth from one room to the other. ,,. ' ' ' . ' The numerical value of the effective temperature index for any given air conditions is fixed by the temperature of calm (15 to 25 fprri air movement) saturated air which induces a like sensation of warmth or cold. Thus, any air condition has an effective temperature of 60 deg, for CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES instance, when it induces a sensation of warmth like that experienced in calm air at 60 deg saturated with moisture. The effective temperature index cannot be measured directly but is computed from the dry- arid wet-bulb temperature for a given air velocity or using charts (see Figs. 6, 7 and 8 or tables). The relation of winter and summer sensations of comfort to wet- and dry-bulb temperature at low air movement is shown in Fig. 6. Relations between moisture content and various dry-bulb temperatures to wet-bulb readings and effective temperatures are depicted 62 Temperature. Applicable to Inhabitants of the United States Under Following Conditions: A. Clothing: Customary indoor clothing. B. Activity: Sedentary or light muscular work. C. Heating Methods: Convection type, i.e. warm air, direct steam or hot water radiators, plenum systems. - 63 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 in Fig. 7. Effective temperatures for various combinations of wet- and dry-bulb temperature readings are given in Fig. 8 accompanied by various air movements. The Comfort Chart shown applies to average normal and healthy persons adapted to American living and working conditions. Application is limited to sedentary or light muscular activity. It will probably not apply to inhabitants of other countries where the living conditions, climate, heating methods, and clothing are materially different than those of the subjects employed in experiments at the Research Laboratory. In rooms in which the average wall surface temperature is considerably below or above air temperature, a correction must be applied to the Fig. 9. Cooling Effect of Three Cold Walls in a Small Experimental Room; as Determined by Comparison with Sensations in a Room of Uniform Wall and Air Temperature readings of the dry-bulb thermometer to allow for such negative or posi tive radiation. In Fig. 9 is given the cooling effect of cold walls ais determined at the A.S.H.V.E. Research Laboratory29 by trained subjects passing back and forth from a small experimental room having three cold walls, to a control room with walls and air at the same temperature/ It can be seen in Fig. 9 that in comparison with air and walls at 70 F in the control (warm wall) room, the cooling effect of three cold walls, at 55 F of the experimental room was 4 F. Therefore, for the same feeling of warmth, the temperature in the experimental room should be increased to 74 F. The reverse would hold in rooms with high wall surface tem perature; a lower air temperature would be required to compensate for positive radiations to the occupants. In Fig. 6 is shown the A.S.H.V.E. winter comfort zone which was Loc. Cit. Note 28. 64 . CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES determined experimentally with large groups of men and women subjects wearing customary indoor winter clothing3031. The extreme comfort zone includes conditions between 60 and 74 deg ET in which one or more of the experimental subjects were comfortable. The average comfort zone includes conditions between 63 and 71 deg ET conducive to comfort in 50 per cent or more of the experimental subjects. The most popular effective temperature was found to be 66 deg, and was adopted by the Society32 as the winter comfort line for individuals at rest wearing custom ary winter clothing. The comfort line separates the cool, air conditions to its left from the warm air conditions to its right. Under the air conditions existing along or defined by the comfort line, the body is able to maintain thermal equilibrium with its environment with the least conscious sensation to the individual, or with the minimum physiologic demand on the heat regulating mechanism. The average winter comfort line (66 deg ET) applies to average Ameri can men and women living inside the broad geographic belt across the United States in which central heating of the convection type is generally used during four to eight months of the year. It does not apply to rooms heated by radiant energy, rooms with excessive glass area or rooms with poorly insulated or cold walls. In densely occupied spaces, such as classrooms, theaters and audi toriums, somewhat lower temperatures may be necessary than those indicated by the comfort line on account of counter-radiation between the bodies of occupants in close proximity33. The sensation of comfort, insofar as the physical environment is con cerned, is not absolute but varies considerably among certain individuals. Therefore, in applying the air conditions indicated by the comfort line, it should not be expected that all the occupants of a room will feel perfectly comfortable. When the winter comfort line is applied in accordance with the foregoing recommendations, the majority of the occupants will be perfectly comfortable, but there will always be a few who would feel o bit too cool and a few a bit too warm. These individual differences among the minority should be counteracted by suitable clothing. Air conditions lying outside the average comfort zone but within the extreme comfort zone may be comfortable to certain persons. In other words, it is possible for half of the occupants of a room to be comfortable in air conditions outside the average comfort zone, but in the majority of cases, if not in all, these conditions will be well within the extreme comfort zone as determined experimentally. For prematurely born infants, the optimum temperature varies from 100 to 75 F, depending upon the stage of development. The optimum relative humidity for these infants is placed at 65 per cent33. No data are yet available on the optimum air conditions for full term infants and* ** Loc. Cit. Note 25. ,lThe Summer Comfort Zone; Climate and Clothing, by C. P. Yaglou and Philip Drinker, (A.S.H.V.E. Transactions. Vol. 35. 1929, p. 269). How to Use the Effective Temperature Index and Comfort Charts '(A.S.H.V.E. Transactions, Vol. 38. 1932. p. 410). **Loc. Cit. Note 31. "Application of Air-Conditioning to Premature Nurseries in Hospitals, by C. P. Yaglou. Philip Drinker, and K. D. Blackfan (A.S.H.V.E. Transactions, Vol. 36, 1930, p. 383). 65 HEATINC VENTILATING AIR CONDITIONING ' GUIDE 1940 young children up to school age. Satisfactory air conditions for these age groups are assumed to vary from 75 to 68 F with natural indoor humidities. For school children, the studies of the New York State Commission on Ventilation place the optimum air conditions at 66 to 68 F temperature with a moderate humidity and a moderate but not excessive amount of air movement35. Satisfactory comfort conditions for men at work are found to vary from 40 to 70 deg ET, depending upon the rate or work and amount of clothing worn36. In hot industries, 80 deg ET is considered the upper limit compatible with efficiency, and, whenever possible, this should be reduced to 70 deg ET or less. The summer comfort zone is much more difficult to fix than the winter zone owing to the complicating factor of sweating in warm weather. A given air condition which is comfortable for persons with dry skin and clothing may prove too cold for those perspiring, as is the case, for in stance, with employees and customers in a cooled store, restaurant, or theater, on a warm summer day. The conditions to be maintained in different types of public buildings depend to a large extent upon the occupant's length of stay and upon the prevailing outdoor condition. In Fig. 6 is shown the summer comfort zone for exposures of 3 hours or more, after adaptation has taken place. The average zone extends from 66 to 75 deg ET, with a comfort line at 71 deg ET, as determined at the Harvard School of Public Healthi37. These effective temperatures average about 4 deg higher than those found in winter when customary winter clothing was worn. The .variation from winter to summer is probably due partly to adaptation to seasonal weather and partly to differences in the clothing worn in the two seasons. The basic summer comfort zone presented in Fig. 6 prescribes con ditions of choice for continuous exposures, as in homes, offices, etc., without regard to costs, prevailing outdoor air conditions, and tempera ture contrasts upon entering or leaving the cooled space. A great number of persons seem to be content with a higher plane of indoor temperature, particularly when the matter of first cost and cost of operation of a cooling plant is given due consideration. . According to previous investigations38, an indoor temperature of about 80 F with relative humidities below 55 per cent, or 74.5 deg ET and lower, results in satisfactory comfort conditions in the living quarters of . a residence, and while this condition is not representative of optimum comfort it provides for sufficient relief in hot weather to be acceptable to the majority of users. Experience in a number of air conditioned office buildings, including the New Metropolitan Life Building in New York33, indicates that a temperature of about 80 F with a relative humidity between 45 and 55 per cent (73 to 74.5 deg ET) is generally satisfactory in meeting the requirements of the employees. . ' BLoc. Cit. Note 12. *Loc. Cit. Note 28. ^Loc. Cit. Note 31. A.S.H.V.E. Research Report No. 1012--Study of Summer. Cooling in the Research Residence for the Summer of 1934. by A. P. Kratz, S. Konzo, M. K. Fahnestock and E. L. Broderick (A.S.H.V.E. Trans-' actions. Vol. 41, 1935, p. 207). The Air Conditioned System of the New Metropolitan Building--First Summer's Experience,, by W. J. McConnell and I. B. Kagey (A.S.H.V.E. Transactions, Vol. 40, 1934, p. 217). 66 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES Recent studies carried out under the auspices of the Society have shown that effective temperatures of 71 F in Toronto, 72 F in Pittsburgh and Minneapolis, and 73 F in Texas, were generally found most comfort able by sedentary workers during the summer months40. The preferred indoor optimum varied with outdoor temperature during successive summer months41; and interesting data were obtained as to contrast effects between indoor and outdoor situations42. In artificially cooled theaters, restaurants, and other public buildings where the period of occupancy is short, the contrast between outdoor and indoor air conditions becomes the deciding factor in regards to the tem perature and humidity to be maintained. The object of cooling such places in the summer is to provide sufficient relief from the heat without causing sensations of chill or intense heat on entering and leaving the building. - The Comfort Chart has proved one of the most valuable tools of the heating and ventilating engineer. Research in other laboratories43 has shown somewhat different quantitative relationships but these are easily accounted for by differences in metabolic activity and clothing. It appears from this other work that the Comfort Chart may perhaps exaggerate somewhat the. influence of relative humidity at low tempera tures and underestimate it at high temperatures; but the chart gives an essentially correct picture of those relations which exist where radiant influences and high air movement are not important factors. PHYSIOLOGICAL OBJECTIVES OF HEATING AND VENTILATION Aside from the removal of toxic fumes and dusts from heating appli ances and industrial processes, the chief task of the heating and venti lating engineer is to keep his clients warm in winter and cool in summer. For the normally vigorous person, normally clothed, and at rest, an air temperature of 65 F should be provided at knee-height, 18 in. in order to prevent chilling of the legs and feet. With some heating systems, this will correspond to 70 F at a 5 ft height. Air temperature may be increased or decreased in order, to compensate for deviations of mean radiant temperature above or below air temperature. In rooms occupied by persons of sub-normal vitality, knee-height temperatures must be higher than 65 F. Since dwellings are designed for occupancy by old people and children, the heating system should be able to provide a temperature of 70 F at knee-height under ordinary winter conditions. <BA.S.H.V.E. Research Report No. 1035--Comfort Standards for Summer Air Conditioning, by F. C. Houghten and Carl Gutberlet (A.S.H.V.E. Transactions. Vol. 42, 1936. p. 215). A.S.H.V.E. Research Report No. 1055--Cooling Requirements for Summer Comfort Air Conditioning, by F. C. Houghten, F. E. Giesecke, C. Tasker and Carl Gutberlet (A.S.H.V.E. Transactions, VoL 43,1937, p. 145). A.S.H.V.E. Research Report No. 1088--Summer Cooling Requirements of-275 Workers in an Air Conditioned Office, by A. B. Newton, F. C. Houghten, Carl Gutberlet, and R. W. Qualley (A.S.H.V.E. Transactions, Vol. 44, 1938. p. 337). Cooling Requirements for Summer Comfort Air Conditioning in Toronto, by C. Tasker (A.S.H.V.E. Transactions, VoL 44, 1938, p, 549). . _ -. . <lA.S.H.V.E. Research Report No. 1088--Summer Cooling Requirements of 275 Workers in an Air Conditioned Office, by A. B, Newton, F. C. Houghten, Carl Gutberlet and R. W. Qualley (A.S.H.V.E. Transactions, Vol. 44, 1938, p. 337). . .* . ^A.S.H.V.E. Research Report No. 1102--Shock Experiences of 275 Workers After Entering and Leaving Cooled and Air-Conditioned Offices, by A. B. Newton, F. C. Houghten, C. Gutberlet, R. W. Qualley, and M;C. W. Tomlinson (A.S.H.V.E, Transactions, Vol. 44, 1938, p. 571). . , "Loc. Cit. Note 9. . ... . 67 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 The maintenance of such conditions as these in winter depends on three major factors, the heat produced in the occupied space, the heat absorbed from the sun and the heat loss through the walls, floor and ceiling of the structure to cold air and earth. Taking these up in the order in which they occur, in planning a new structure it is essential to remember the important effect of orientation and fenestration of the building with respect to the absorption of radiant heat from the sun. It has recently been shown that, in the vicinity of New York effective sun-heat on a wall facing south is almost five times as great in winter as in summer, but on a wall facing west-north-west it is six times as great . in summer as in winter44. The orientation of the same one-story house (in a laboratory model) was changed from a position in which its principal rooms faced northwest to a position in which these rooms (with re arranged and slightly increased fenestration) faced west of south. This change decreased average summer sun-heat to one-ninth and increased average winter sun-heat to fourfold of its value with the original ori entation. The choice between the various methods of heating depends, of course, on many engineering and other factors. From the standpoint of human health and comfort, however, it is important to minimize floor-ceiling differentials as far as possible to avoid hot heads and cold feet. Further more, when the problem is a heating one, low air movement is desirable, since air temperature must be raised to balance the cooling effect of air motion. Where occupants are closely aggregated, a new problem comes in, the removal of the excess heat produced by the human body itself. If the temperature of such a space be correctly adjusted when the occupants enter, it will steadily rise during the period of occupancy as a result of the heat produced by the occupants in the process of metabolism. Of the 400 Btu given off in metabolism 100 would perhaps be lost in evaporation, leaving 300 Btu per person per hour to warm the air. In a room contain ing many persons, the effects of this body heat can be neutralized by outside air without producing unpleasant and dangerous drafts on .those . near the windows or other inlets. The supply of air should be so tempered as to avoid drafts but in an amount and at a temperature which will remove the sensible heat produced by human metabolism. With no heat loss through walls (as in an interior auditorium) this will require 28 cfm of air per person with admitted air at 60 F and a maximum figure of 70 F, for air leaving the room. Under practical conditions, with one ' or more cold walls, and a room containing a moderate number of occu pants and ample cubic space, window ventilation with deflectors and.;a i gravity exhaust duct may suffice. With crowded rooms, and with any rooms containing 50 or more occupants, forced ventilation will be essential. SUMMER COMFORT The problem of keeping cool in summer is physiologically as important as keeping warm in winter. In summer the relative humidity of the atmosphere is of importance, along with air temperature, air movement, So]ar Radiation as Related to Winter Heating in Residences, by H. N. Wright (Report of John B. Pierce Foundation, January 20. 1936). 68 CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES and wall temperature. There is no very practical method of cooling walls, but summer comfort can be promoted by modifying either one of the other three factors involved. Increase of comfort by air movement can be effected in two ways. The first of these is promotion of natural circulation by cross or through ventilation; and here the architect is responsible for providing room planning and fenestration which will make such natural ventilation possible. In the lowest cost housing this should be considered as essential. The direct control of air temperature and humidity is, of course, the ideal solution where the cost of a complete air conditioning equipment can be met. Where this objective is attained, there are two schools of thought concerning the relation between temperature and humidity to be maintained. For a given effective temperature some engineers favor comparatively low temperature with a high humidity as this results in a reduction of refrigeration requirements. Preliminary experiments at the A.S.H.V.E. Laboratory45 would seem to indicate no appreciable impair ment of comfort with relative humidities as high as 80 per cent, provided the effective temperature is between 70 and 75 deg. The second school favors a higher dry-bulb temperature, according to the prevailing outdoor dry-bulb, with a comparatively low humidity (well below 50 per cent), the main purpose being to reduce temperature contrasts upon entering and leaving the cooled space and to keep the clothing and skin dry. This second scheme requires more refrigeration with the present conventional type of apparatus. In connection with summer cooling mention should be made of the danger of over-doing it. Possible impairment to health may have resulted from the sharp contrast between air conditioned trains and the outside atmosphere in the early days of this practice. Current practice in theaters, restaurants, etc., follows a schedule similar to that shown in Table 5. This schedule should be used with considerable judgment, depending on the occupancy and local climatic conditions. There are some in dications that a definite indoor effective temperature may be applicable throughout the cooling season, but other observations seem to show that changing indoor conditions are desirable with violently changing outdoor weather conditions. It is questionable whether entirely satisfactory air conditions could be adduced for practical use to meet the changing requirements of patrons from the time they enter to the time they leave a cooled space. Too many uncontrollable variables enter into the prob lem. Work now going on at the A.S.H.V.E. Research Laboratory and other institutions may throw considerable light on this complex problem. For cooled banks and stores where the customers come and go, spending but a few minutes in the cooled space, observations indicate a schedule about 1 deg dry-bulb of effective temperature higher than that shown in Table 5. Laboratory experiments with exposures of 2 to 10 min indicate temperatures 2 to 10 F higher than those in Table 5, but with much lower relative humidities. , It should be kept in mind that southern people, with their more sluggish "A.S.H.V.E. Research Report No. 1035---Comfort Standards for Summer Air Conditioning, by F. C. . Houghten and Carl Gutberlet (A.S.H.V.E. Transactions, Vol. 42, 1936, p. 215). A.S.H.V.E. Research . Report No. 1055--Cooling Requirements for Summer Air Conditioning, by F. C. Houghten, F. E. Giesecke, C. Tasker and Carl Gutberlet (A.S.H.V.E'. Transactions, Vol. 43,1937, p. 145.) 69 HEATINC VENTILATING AIR CONDITIONING CUIDE1940 heat production and lack of adaptability, will demand a comfort zone several degrees higher than that for the more active people of northern climates. Instead of the summer comfort lines standing at 71 deg ET as here given, it was found to be much higher for foreigners in Shanghai where climatic conditions are similar to those of our gulf states. This difference in adaptability of people forms a very real problem for air conditioning engineers. Cooling of theaters, restaurants, and other public buildings in southern climates cannot be based on northern standards without considerable modification. Table 5. Desirable Inside Conditions in Summer Corresponding to Outside Temperatures3 Occupancy Over Jfi Min Outside Dbt-Bulb Deo F 100 95 90 85 80 ' Effective Temperature 75 75 75 75 74 74 74 74 74 73 73 73 73 72 72 72 72 71 71 71 71 Inside Am Conditions . Dry-Bulb Deg F 83 82 81 80 82 81 80 79 78 81 80 79 78 80 79 78 77 . 78 77 76 75 Wet-Bulb Deg F 66 67 68 70 64 66 67 68 70 63 64 66 67 61 63 64 66 61 63 64 66 Dew-Point Deg F 56 59 . 61 65 53 57 60 62 66 52 54 59 . 61 48 53 56 60 49 54 57 61 Relative Humid ' ity Per Cent 40 45 51 60 36 44 51 57 68 36 41 50 56 32 41 46 56 36 45 52 61 .Applicable to individuals engaged in sedentary or light muscular activity. RELATION OF AIR AND WALL TEMPERATURES In the previous discussion, it has generally been assumed that air and.', wall temperatures are alike and, of course, this is roughly the case. In a room heated by pure convection, the walls are generally heated by the warm air.and in a room heated by pure radiation, the air is. gradually warmed by convection from surfaces which have themselves been, warmed by absorption of radiant heat. In ordinary indoor spaces, whatever the heating method, the mean of floor, ceiling and all four walls, is not likely to differ more than 3 F from the air temperature; but individual walls; which have a dominant effect on certain areas of the room may be 20 F below air temperature46 (see Fig. 9). < '^^WelH Surface Temperatures, by A. C. Willard and A. P. Kratz (A.S.H.V.E. Transactions, Vol. 36. CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES With an open fire, or a high temperature radiant heater the influence of radiant heat may be considerable; and with large window areas the converse cooling effect may be important. Outdoors in the sun, the influence of radiation is, of course, enormous. Where substantial differ ences between air and surrounding surfaces (or special radiant heat sources) do exist, this factor must be taken into account. An interesting point indicated by the studies at the John B. Pierce Laboratory, is that when a given operative temperature (that is, the temperature which should physically exert a certain heat-demand upon a body of fixed surface temperature) is produced by (1) air and walls at approximately the same temperature, and (2) colder air and warmer walls (in the zone of body cooling), the skin temperature falls to a lower point for the cold air warm wall situation, thus decreasing the actual rate of heat loss. The reason for this effect is somewhat obscure but it is believed to be related to local stimulation by the colder air exerted on the mem branes of the nose and throat and to the greater chilling of the exposed skin surfaces when those parts of the body are moved. INFLUENCE OF HUMIDITY Recent research indicates that, from the physiological viewpoint: 1. In the hot zone (above a point of ideal adjustment and comfort) high relative humidity tends to prevent evaporative regulation and is exceedingly harmful. Even when evaporation of sweat maintains a successful thermal balance, the process is ac companied by marked discomfort and interference with physical efficiency; and high relative humidity sharply narrows the zone of temperature within which adjustment can take place, a rise from 0 to 100 per cent relative humidity (under conditions cited in a preceding paragraph) lowering the limit of air-temperature tolerance by 40 deg (see Fig. 2 and the Table 2 giving upper limits of evaporative regulation). 2. In the cold zone relative humidity has comparatively slight influence, lowering relative humidity from 75-80 per cent down to 30-35 per cent increasing heat loss only by the same amount as a 1 deg fall in temperature. For the premature infant, a high relative humidity of about 65 per cent is demonstrably beneficial to health and growth47 until the infants reach a weight of about 5 lb. No such clear-cut evidence exists in the case of adults. In the comfort zone experiments of the A.S.H.V.E. Research . Laboratory, the relative humidity was varied between the limits of 30 and 70 per cent approximately, but the most comfortable range has not been determined. In similar experiments at the Harvard School of Public Health, the majority of the subjects were unable to detect sensa tions of humidity (i.e., too high, too low, or medium) when the relative humidity was between 30 per cent and 60 per cent with ordinary room temperatures which is in accord with other studies48,49. The limitation of the comfort zones in Fig. 6 with respect to humidity must not be taken too seriously. Relative humidities below 30 pier cent may prove satisfactory from the standpoint of comfort: In mild weather comparatively high relative humidities are entirely, feasible, but in cold 4rLoc. Cit. Note 34. ' '. . . . "Humidity and Comfort, by W. H. Howell (The Science Press, April, 1931). ' "Effect of Variation in Relative Humidity upon Skin Temperature and Sense of Comfort, by U. Miura (American Journal of Hygiene, Vol. 13, 1931, p. 432). ................ ' 7i: HEATING VENTILATING AIR CONDITIONING CUIDE 1940 or sub-freezing weather they are objectionable on account of condensation and frosting on the windows. Information on this subject is given in Chapter 7. A degree of atmospheric humidity sufficiently high to cause deposition of moisture in the clothing may perhaps increase the chilling effects of cold air; but little or no exact information is available on this point. The dividing line at which humidity has no effect upon warmth varies with the air velocity and is about 46 F (dry-bulb) for still air and about 50, 56 and 60 F for air velocities of 100, 300 and 500 fpm, respectively. CHAPTER 3. PHYSICAL AND PHYSIOLOGICAL PRINCIPLES: INFLUENCE OF AIR MOVEMENT The problem of the influence of air movement is a highly complex one as illustrated in Fig. 10, where heat losses per unit of body surface by radiation, convection and evaporation are plotted against air temperature for three different rates of air movement (with 50 per cent relative humidity). It will be noted that: 1. Evaporative heat loss is constant and minimal at air temperatures below 80 F and is relatively uninfluenced in this area by air movement. With low air movement, sweat secretion begins to rise at 80 F, but with very high air movement only the rise does not begin until 87 F (because, with high air movement, the body cools more readily by convection and hence the sweat secreting mechanism, need not operate at so low an air temperature). Above this critical point, evaporation increases very sharply with increasing air temperature. . ... Fig. 10. Changes in Distribution of Heat Loss by Radiation, Convection, and Evaporation at Various Air Temperatures with Three Different Air Movements i As to the effects of dryness of the air, per se, and irrespective of thermal effects, there is a common belief that dry air in itself exerts a harmful effect upon the skin and mucous membranes; but there is no convincing evidence that the increase of atmospheric moisture which can practically be introduced by humidification into the air of cool occupied rooms has any effect upon health and comfort. All controlled experiments on this point have yielded negative results; and the respiratory membranes of industrial workers exposed to hot moist air are distinctly more abnormal than those of workers exposed to hot dry air50. *Loc. Cit. Note 12. 72 Fig. 11. Contour Chart Indicating Upper Limits (Wetted Area = 100 per cent) of the Zone of Evaporative Regulation for Various Air Velocities for Unclothed Subjects ' 2. Heat loss by radiation is decreased as air movement increases because the greater influence of convection, when'air movement is high, lowers the skin temperature and thus lowers radiation which depends on the differential between walls and body surface. 3. Convection rises at all points sharply with increased air movement, according to a relation discussed in a succeeding paragraph. It will be noted that the proportionate heat loss by the three processes involved varies widely, as indicated in Table 6. At air temperatures above the temperatures of the body surfaces, the body will, of course, be gaining heat by convection and losing heat only by evaporation. Increased air movement will favor both these processes and its net effect will depend on the relative humidity of the atmosphere. The phenomena involved are illustrated in Fig. 11 which shows the influence of air movement (at varying air temperatures and humidities) upon the upper limit of the zone of evaporative regulation. It will be noted that (for the nude subject in a semi-reclining posture) increase in air 73 1 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 3. PHYSICAL AND PHYSIOLOCICAL PRINCIPLES movement consistently increases evaporative cooling, and therefore heat tolerance, when relative humidity is high and air temperature low. When relative humidity is low and air temperature is high, however, an increase of the air current is 40 fpm and the temperature of the air current 2 F or more below the customary winter room temperature. Higher velocities are desirable in the summer time when the air temperature exceeds 80 F. tei in air velocity from 17 to 30 or 100 fpm actually decreases heat tolerance. Under these conditions air temperature is above skin temperature and Variations in air movement and temperature in different parts of occupied rooms are often indicative of relative air distribution. The work of the the increased demand for evaporative cooling exceeds the actual increase of evaporation due to the higher air movement. When an air velocity of A.S.H.V.E. Research Laboratory indicates that an air movement between 15 and 25 fpm with a temperature variation of 3 F or less in different 500 fpm is reached, the limits of the zone are broadened throughout its parts of a room, 36 in. above floor, represent satisfactory distribution. range. For very hot and dry environments, still air is more desirable than a slightly greater air movement but a high air movement is still THE FOUR VITAL FACTORS better. At low air temperatures the effect of increased air movement upon convection loss is a simple and direct one; but the exact quantitative influence of air movement upon the rate of cooling of a hot body has, until recently, been unknown. Studies at the John B. Pierce laboratory of Hygiene, as yet unpublished, have indicated that the cooling effect of air From the preceding discussion it is clear that thermal environment cannot properly be adjusted to the requirements of human health and comfort without control of all the four basic factors concerned. According to the recommendations of the Sub-Committee on the Hygiene of Environmental Conditions in the Dwelling62, it is of great actually increases as the square root of its velocity. Under the conditions Table 7. Corresponding Equivalent Air Temperatures Producing Equal Heat Loss at 15 fpm for Various Air Temperatures and Air Movements Table 6. Percentage of Total Heat Loss Effected by the Three Chief Routes of Thermal Interchange Air Temperature.. Deg F 60 70 80 90 Observed Ambibnt Air Temperature Dec F Equivalent temperature at standard air move- ment op 15 fpm when observed air movement is ____________________ _________________________________________________ 15 fpm 100 fpm 250 fpm 500 fpm Air Movement__ fpm 15 100 250 15 100 250 15 100 250 15 100 250 Evaporation_____ per cent 18 lfr' IS 22 19 18 29 27 25 73 67 55 Radiation...._____ per cent 43 26 19 40 26 17 37 24 17 14 10 13 Convection............ per cent 39 58 66 38 55 65 34 49 58 13 23 32 of the experiments in question (semi-reclining lightly clothed subjects), the effect is represented by the formula: - 95 95 95.0 95.7 96.0 90 90 88.5 87.7 87.0 85 85 81.7 79.5 78.0 80 80 75.2 71.6 69.0 75 75 68.7 . 63.5 . 60.3 70 70 62.2 55.5 51.2 65 65 55.5 47.5 42.5 60 60 48.9 39.5 33.6 55 55 42.3 31.8 24.7 50 50 35.7 23.5 15.8 -f = 0.413 VET * (2) where ' C = Convection loss in kilogram-calories per square meter of body surface per hour. A T -- Surface temperature of the body (clothing and exposed skin) minus air* temperature, degrees Fahrenheit. V = Velocity of air, feet per minute. The extent of the effect may be indicated by the computed data in Table 7. As emphasized in an earlier paragraph the problem of local drafts causing differential cooling of special areas of the body is one that must always be kept in mind. Experience, and recent field studies by theJ A.S.H.V.E. Research Laboratory61 place the desirable air movementbetween 15 and 25 fpm under ordinary room temperatures during the heating season. Objectionable drafts are likely to occur when the velocity importance in all research studies to make an accurate record of each of the four independent factors governing bodily heat exchanges, tempera ture, movement and humidity of the air, and mean radiant temperature of the surrounding surfaces. For this purpose the committee suggested in the interest of comparability the use of the following four types of instruments or others yielding similar data: 1. Silvered dry-bulb thermometers or hair-pin thermometers (Bargeboer). 2. Silvered dry Kata-thermometers or the hot wire anemometer. 3. Psychrometer, wet- and dry-bulb, whirling or ventilated. 4. Globe thermometer (Vernon) or the dry resultant thermometer (Missenard). Such instruments as these, when properly calibrated and their readings are compared, can be used for determining the four basic physical factors concerned separately or in certain combinations. The results of the four physical measurements thus determined can generally be translated into the terms of any special instrument combining two or more of them. nA.S.H.V.E. Research Report No. 1016--Classroom Drafts in Relation to Entering Air Stream Temperature, by F. C. Houghten, H. H. Trimble, Carl Gutberlet, and M. F. Lichtenfels (A.S.H.V.E. Transactions, Vol. 41,1935, p. 268). 74 ''Housing Commission of the League of Nations, adopted at Geneva, June 25, 1937. 75 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 !lj In some instances it may be important to record not only the movement :j' and temperature of the air at various levels, but also the temperature of jj each wall and window, of the flooring, and of the ceiling, and to measure i|j the totaleffective radiation of the surroundings in 6 directions; in order to trace the exact causes of defects in the building which have an unk favorable influence on the heat exchanges of its inhabitants. Facts of ij' this type are of great practical importance. C; In all fundamental studies of air conditions records should be obtained, Vj therefore, showing: , 1. True air temperature (free from radiation effects), ff 2. Air movement. ' j 3. Humidity. | 4. Mean radiant temperature of surrounding surfaces. Ij In interpreting the results of such studies, the clothing and the physical I activity of the subjects are of primary importance. Chapter 4 AIR POLLUTION ,Classification of Air Impurities Dust Concentrations, Air , ,Pollution and Health Occlusion of Solar Radiation Smoke , ,and Air Pollution Abatement Dust and Cinders Nature9s Dust Catcher , THE particulate impurities which contribute to atmospheric pollution include carbon from the combustion of fuels, particles of earth, sand, ash, rubber tires, leather, animal excretion, stone, wood, rust, paper, threads of cotton, wool, and silks, bits of animal and vegetable matter, and pollen. Microscopic examination of the impurities in city air shows that a large percentage of the p&rticles are carbon. 1 CLASSIFICATION OF AIR IMPURITIES The most conspicious sources of atmospheric pollution may be classified in various ways; as dusts, fumes and smoke. In Fig. 1, the classification is by particle size, but recent practice favors differentiation by method of formation. Thus, dusts are composed of particles produced by disintegration of larger material, as by crushing or grinding, whereas fumes are produced by condensation, and smoke consists of the finer carbon particles resulting from incomplete combustion. Similarly, mists are formed by the breaking up of liquids and fogs by condensation of vapors. There is as yet, however, no general agreement on these terms. Dusts tend to settle without agglomeration, fumes to aggregate and smoke to diffuse. Particles which approach the common bacteria in size--from 1 to 10 microns--are difficult to remove from air and are apt . to remain in suspension unless thay can be agglomerated by artificial means. The term fly-ash is usually applied to the microscopic glassy spheres which form the principal solid constituent of the effluent gases from powdered-coal fired furnaces. Cinders denote the larger solid constituents which may be entrained by furnace gases. . Particles larger than 10 microns are unlikely to remain suspended in air currents of moderate strength. Only violent air motion will sustain them in air long enough for them to be breathed. This means that, in hygenic problems, the engineer is concerned mostly with suspensions of particles comparable to the common bacteria in size.- A notable exception to this size limitation is the common hay-fever producing pollen such as that from rag-weed. Pollen grains may be anything from fragments 15 microns in diameter to whole pollens 25 microns or more in size. 76 77 -A f&fiS HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Although it is possible under certain conditions to recognize the presence of particles smaller than 10 microns, the normal eye is unable to resolve any dimension under about 50 microns, and thus all air floated material of this kind is too small to identify without the aid of a micro scope. Fig. 1. Sizes and Characteristics of Air-Borne Solids Mineral particles, such as grains of sand, bits of rock, volcanic ash, or fly-ash, can be transported long distances under unusual circumstances. Thus, the dust storms of 1935 in the Kansas district resulted in vast amounts of fine top soil being thrown high into the air. Solar illumination 78 CHAPTER 4. AIR POLLUTION Table 1. Approximate Limits of Inflammability of Single Gases and Vapors in Air at Ordinary Temperatures and Pressures* Gab or Vapor Lower Limit Volume in Per Cent Higher Limit Volume in Per Cent Hydrogen................................................................................... Ammonia................................................................................... Hydrogen sulphide.............................................................. Carbon disulphide................ ............................................. Carbon monoxide......................... ..................................... Methane......................................... ................. ~....................... Methane (turbulent mixture)..................................... Ethane.........................................................................-.............. Propane................................................................ --.............. Butane........................................................... ............... .............. Pentane.......... ........................................................................... Ethylene...................................... -.............. ---....................... Acetylene............-- ----------------------------------- ----------------Acetylene (turbulent mixture)........... -..................... Benzene.............................................. ...................................-- Toluene.-------- -.................................................................. Cyclohexane.___________________ ....................................... Ethyl alcohol....... ..................... ...... . _______ _ Ethyl ether.---------------- ----- -......................... ........ .............. Benzine.................. --.................................... ......................... Gasoline....... .......................... ...................................... Water gas.................................................................................. Ethylene oxide. ............ ................. _................................ Acetaldehyde...... .................................................................... Acetone.................................... ........... ........................... ......... Acetone (turbulent mixture)..................... ................... Methyl ethyl ketone^-...................................................... Methyl formate________________ _____ ______ _______ Ethyl formate.......... .. ..................................... ................. Methyl acetate.____ ................ ..................... ............. ....... Ethyl acetate....... ............................ ............................. Propyl acetate Butyl acetate (30 C) Ethyl nitrite. ........................... .............................. ... .......... Methvl chloride..... Methyl bromide....... ............................................................. Ethyl chloride Ethyl bromide Ethylene dichloride. Dichlorethvlene Vinyl chloride ... ................................ ....... . .. Pvridine (70 C) Natural gas Illuminating gas Blast-furnace gas...................................................... ,,........ '4.1 16.0 4.3 1.0 12.5 5.3 5.0 3.2 2.4 1.9 1.45 3.0 3.0 2.3 1.4 1.4 1.3 1.2 7.0 4.0 1.7 1.1 1.4 6 to 9 3.0 4.0 2.0 3.0 2.5 2.0 6.0 3.5 4.1 2.5 2.0 1.7 3.0 8.0 13.5 4.0 7.0 6.0 10.0 4.0 1.8 4.8 5.3 35.0 , , 74.0 27.0 46.0 50.0 74.0 14.0 15.0 12.5 9.5 8.5 7.5 29.0 ____ 7.0 7.0 8.3 19.0 26.0 6.0 55 to 70 80.0 57.0 11.0 12.0 20.0 16.5 14.0 11.5 19.0 .14.5 15.0 11.0 16.0 13.0 22.0 12.5 13.5 31.0 74.0 Min`tLsi,mBituslloeftinInNflaom. 2m79a,b1ili9ty31o).f Gases and Vapors, by H. F. Coward and G. W. Jones, (U. S. Bureau ol 79 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 as far east as Boston was affected noticeably and particles as large as 40 to 50 microns were actually carried half way across the continent before they settled out. In similar manner volcanic ash has been carried even further. It is not surprising, therefore, that fly-ash from furnace gases, cement dust and the like, can be carried for considerable distances and occasionally the engineer is confronted with the problem of removing such material before the air in "question is suitable for use in building venti lation. . The physical properties of the particulate impurities of air are summar ized conveniently in the chart of Fig. 1. . In the case of gases, the objectionable features are the injurious physiological effects and the danger from inflammability. See Table 1. Dust Concentrations It is customary to report dust concentrations as grains per 1000 cu ft or milligrams per cubic meter. Gas concentrations are commonly re corded as milligrams per cubic meter or as parts per million or as per cent by volume. Typical'ranges in dust concentrations as now found in practical applications are given in Table 2. Table 2. Dust Concentration Ranges in Practical Applications* Application Gbaikb Per 1000 Cu Ft Mgs Phb Cu M: Explosive concentrations (as of flour or soft coal).. 0.2 to 0.4 0.4 to 0.8 0.8 to 1.5 4.0 to 80.0 4000 to 8000 0.4 to 0.8 . 0.9 to i:8 1.8 to 3.5 10 to 200 10,000 to 20,000 *1 gr per 1000 cu ft * 2.3 mgs per cubic meter; 1 oz per cubic foot = 1 g per liter. The engineer frequently desires information regarding the effects ofvarious concentrations of gases or dusts upon man, as the success of a particular installation may depend upon the maintenance of air which is adequately clean. At the present time there are several organi zations working on this problem all of them publishing literature, of various kinds.1 References to books covering the hygienic significance, determination and control of dust are listed at the end of this chapter, i AIR POLLUTION AND HEALTH . The prevention of various diseases which result from exposure to atmospheric impurities is an engineering problem. It is important for the engineer to insure, by proper ventilation, suitable environments for working or for general living. If the equipment used is to be successful, it must operate automatically as in the modern air conditioned theatre or railroad train. In Table 3 are given data on permissible concentrations of various substances, gases and dusts, which occur in industry. The prudent `National Institute for Health. U. S. Public Health Service; Division of Labor Standards. U. S. Depart ment of Labor; University of Toronto Medical School. Canada; Saranac Laboratories. Saranac Lake, N. Y.; Air Hygiene Foundation, Inc.. Pittsburgh, Pa.; Haivard School of Public Health. Boston, Mass.; Haskell Laboratory, Wilmington, Del.; and the Departments of Health and of Labor in the United States and in various provinces of Canada. 80 CHAPTER 4. AIR POLLUTION engineer will design equipment using these bench marks as the upper limits of pollution. In general it is good practice to avoid recirculation of air which contains originally toxic substances. Obviously there may be exceptions to this rule, but it is one which is generally being followed in current practice. . Bronchitis is the chief condition associated with exposure to thick dust, and follows upon inhalation of practically any kind of insoluble and noncolloidal dust. Atmospheric dust in itself cannot be blamed for causing tuberculosis, but it may aggravate the disease once it has started.2 . Table 3. Toxicity of Gases and Fumes in Parts per 10,000 Parts of Air* Vapor or Gas Rapidlt Fatal Maximum Concentration FOR PROM H to 1 Hour Maximum Concentration fob 1 Hour Maximum Allowable fob Prolonged Exposure . Carbon monoxide.............. Carbon dioxide................... Hydrocyanic acid............... Ammonia......... -.................. Hydrochloric acid gas. .... Chlorine............................... Hydrofluoric acid gas____ Sulphur dioxide. ............. Hydrogen sulphide............ Carbon bisulphide._______ Phosphene........... ................ Arsine_____________ ______ Phosgene.............-............... Nitrous fumes..................... Benzene-------- --------------...:. Toluene and xylene........... Aniline.................................. 40 800-1000 30 50-100 . 10-20 10 2. 4-5 10-30 20 2X Over M 2H-7^ 190 190 Carbon tetrachloride........ Chloroform.......................... Tetrachlorethane. Trichlorethylene................. Methyl chloride...... ........... Methyl bromide................. Lead dust._______ :___ __ _ Quartz dust______________ 480 250 73 370 1500-3000 200-400 15-20 IX 25 X XMo X-i 5-7 11 4-6 X M 1-1X 240 140 200-400 20-40 -- 10 X 3 . 2-3 5 1-2 X 31-47 31-47 1-lX Hoo ; 40 50 70 10 ----- i X i Mo Mo l . 1X-S Ho Moo 1 2 M0 . ' : ; 5-10 2 0.15 mg/cu m 1 mg/cu m .Adapted from Y. Henderson and H. Haggard. (See Noxious Cases, 1927, and Lessons Learned from Industrial Cases and Fumes, Institute of Chemistry of Great Britain and Ireland, London, 1930.) - The sulphurous fumes and tarry matter in smoke are more dangerous than the carbon. In foggy weather the1 accumulation of these substances in the lower strata may be such as to cause irritation of the eyes, nose, and respiratory passages. The Meuse Valley fog disaster will probably become a classic example in the history of gaseous air pollution. Released in a rare combination of atmospheric calm and dense fog, it is believed that sulphur dioxide and other toxic gases from the industrial region of the valley caused 63 sudden deaths, and injuries to several hundred persons. . Carbon monoxide from automobiles and from chimney gases consti tutes another important source of aerial pollution in busy cities. During 'Physiological Response of the Peritoneal Tissue to Dusts Introduced as Foreign Bodies, by MUler and Sayers </. S. Public Health Reports, 49:80. 1934). . .w TM 81 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 heavy traffic hours and under atmospheric conditions favorable to con centration, the air of congested streets is found to contain enough CO to menace the health of those exposed over a period of several hours, par ticularly if their activities call for deep and rapid breathing. In open air under ordinary conditions the concentration of CO in city air is insufficient to affect the average city dweller or pedestrian. Occlusion of Solar Radiation The loss of light, particularly the occlusion of solar ultra-violet light due to smoke and soot, is beginning to be recognized as a health problem in many industrial cities. Measurements of solar radiation in Baltimore5 by actinic methods show that the ultra-violet light in the country was. 50 per cent greater than in the city. In New York City4, a loss as great as 50 per cent in visible light was found by the photo-electric cell method. Recent studies5 in Pittsburgh indicate that heavy smoke pollution is definitely unhealthful. Heretofore adequate proofs on this point were lacking. The aesthetic and economic objections to air pollution are so definite, and the effect of air-borne pollen can be shown so readily as the cause of hay fever and other allergic diseases, that means and expenses of pre vention or elimination of this pollution are justified. SMOKE AND AIR POLLUTION ABATEMENT Successful abatement of atmospheric pollution requires the combined efforts of the combustion engineer, the public health officer, and the public itself. The complete electrification of industry and railroads, and the separation of industrial and residential communities would aid materially in the effective solution of the problem. In the large cities where the nuisance from smoke, dust and cinders is the most serious, limited areas obtain some relief by the use of district heating. The boilers in these plants are of large size designed and oper ated to burn the fuel without smoke, and some of them are equipped with dust catching devices. The gases of combustion are usually discharged at a much higher level than is possible in the case of buildings that operate their own boiler plants. i In general, time, temperature and turbulence are the essential require ments for smokeless combustion. Anything that can be done to increase any one of these factors will reduce the quantity of smoke discharged.Especial care must, be taken in hand-firing bituminous coals. (See Chapter 9.) Checker or alternate firing, in which the fuel is fired alternately on separate parts of the grate, maintains a higher furnace temperature and thereby decreases the amount of smoke. Coking and firing, in which the fuel is first fired close to the firing door and the coke pushed back into the furnace just before firing again, pro- Effects of Atmospheric. Pollution Upon'Incidence of Solar Ultra-Violet Light, by J. H. Shrader, M. H Coblentz and F. A. Koiff (American Journal of Public Health, p. 7, Vol. 19, 1929). . Studies in Illumination, by J. E. Ives (U. S. Public Health Service Bulletin No. 197, 1930). Pneumoconiosis in the Pittsburgh district. Based on a Study of 2,500 Post Mortem Examinations.made in Pittsburgh Hospitals, by Schnurer et al (Journal Industrial Hygiene, 17:294, March, 1935). 82 ' CHAPTER 4. AIR POLLUTION duces the same effect. The volatiles as they are distilled thus have to pass over the hot fuel bed where they will be burned if they are mixed with sufficient air and are not cooled too quickly by the heat-absorbing surfaces of the boiler. Steam or compressed air jets, admitted over the fire,-create turbulence in the furnace and bring the volatiles of the fuel more quickly into contact with the air required for combustion. These jets are especially helpful for the first few minutes after each firing. Frequent firings of small charges shorten the smoking period and reduce the density. Thinner fuel beds on the grate increase the effective combustion space in the furnace, supply more air for combustion, and are sometimes effective in reducing the smoke emitted, but care should be taken that holes are not formed in the fire. A lower volatile coal or a higher gravity oil always produces less smoke than a high volatile coal or low gravity oil used in the same furnace and fired in the same manner. The installation of more modern or better designed fuel burning equip ment, or a change in the construction of the furnace, will often reduce smoke. The installation of a Dutch oven which will increase the furnace volume and raise the furnace temperature often produces satisfactory results. .. In the case of new installations, the problem of smoke abatement can be solved by the selection of the proper fuel-burning equipment and furnace design for the particular fuel to be burned and by the proper operation of that equipment. Constant vigilance is necessary to make certain that the equipment is properly operated. In old installations the solution of the problem presents many difficulties, and a considerable investment in special apparatus is necessary. .Legislative measures at the present time are largely concerned with the smoke discharged from the chimneys of boiler plants. Practically all of the ordinances limit the number of minutes in any one hour that smoke of a specified density, as measured by comparison with a Ringelmann Chart (Chapter 45), may be discharged. These ordinances do not cover the smoke discharged at low levels by automobiles, and, although they have been instrumental in reducing the smoke emitted by boiler plants, they have, in many instances, increased the output of chimney dust and cinders due to the use of more excess air and to greater turbulence in the furnaces. Legislative measures in general have not as yet covered the noxious gases, such as sulphur dioxide, nor sulphuric acid fog, which are dis charged with the gases of combustion. Where high sulphur coals are burned, these sulphur gases present a serious problem. DUST AND CINDERS The impurities in the air other than smoke come from so many sources that they are difficult to control. Only those which are produced in large quantities at a comparatively few points, such as the dust, cinders and fly-ash discharged to the atmosphere along with the gases of com bustion from burning solid fuel, can be readily controlled. . Dusts and cinders in flue gas may be caught by various devices on the 83 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 market, such as fabric filters, dust traps, settling chambers, centrifugal separators, electrical precipitators, and gas scrubbers, described in Chapter 27. '- The cinder particles are usually larger in size than the dust particles; they are gray or black in color, and are abrasive. Being of a larger size, the range within which they may annoy is limited. The dust particles are usually extremely fine; they are light gray of yellow in color, and are not as abrasive as cinder particles. Being ex tremely fine, they are readily distributed over a large area by air currents: The nuisance created by the solid particles in the air is dependent on the size and physical characteristics of 'the individual particles. The difficulty of catching the dust and cinder particles is principally a function of the size and specific gravity of the particles. Lower rates of combustion per square foot of grate area will reduce the quantity of solid matter discharged from the chimney with the gases of combustion. The burning of coke, coking coal, and sized coal from which the extremely fine coal hasbeen removed will not as a general rule produce as much dust and cinders as will result from the burning of non-coking coals and slack coals when they are burned on a grate. Modern boiler installations are usually designed for high capacity per square foot of ground area because such designs give the lowest cost of construction per unit of capacity. Designs of this type discharge a large quantity of dust and cinders with the gases of combustion, and if pollution of the atmosphere is to be prevented, some type of catcher must. be installed. NATURE'S DUST CATCHER Nature has provided means for catching solid particles in the air and depositing them upon the earth. A dust particle forms the nucleus for each rain drop and the rain picks up dust as it falls from the clouds to the earth. However, it was found in recent studies6-that rain was not a good air cleaner of the material below about 0.7 micron. REFERENCES Bulletin, Air Hygiene Foundation, Inc., Pittsburgh, Pa. . Determination and Control of Industrial Dust, by J. J. Bloomfield and J. M. Dalla Valle (U. S. Public Health Bulletin, No. 217, 1935). . L Journal of Industrial Hygiene and Toxicology, Harvard School of Public Health, Boston, Mass. .. Reports of the National Silicosis Conference: Washington, D. C.. To be published by the U. S. Department of Labor. Saranac Symposium on Silicosis, 1937, Saranac Laboratories, Saranac, N. Y. Industrial Dust, by Philip Drinker and Theodore Hatch, McGraw Hill Co., N. Y. Noxious Gases, by Y. Henderson and H. Haggard, Chemical Catalog Co., N. Y. Occupation and Health, International Labour Office. . . Preventive Medicine and Hygiene, by Milton J. Roseriau, D. Appleton-Century Co., N. Y. '. ` ' .- . Atmospheric Pollution of American Cities ior the years 1931-1933. by 1. E. lyes et al (U. 5. Public 'Health Bulletin No. 224. March, 1936). 84 Chapter 5 HEAT TRANSMISSION COEFFICIENTS AND TABLES Methods of Heat Transfer, Coefficients, Conductivity of Homogeneous Materials, Surface Conductance Coefficients, Air Space Conductance, Practical Coefficients, Table of Con ductivities and Conductances, Tables of Over-all Coefficients of Heat Transferfor Typical Building Construction, Combined Coefficients of Transmission IN order to maintain comfortable living temperatures within a building it is necessary to supply heat at the same rate that it is lost from the building. The loss of heat occurs in two ways, by direct transmission through the various parts of the structure and by air leakage or filtration between the inside and outside of the building. The purpose of this chapter is to show methods of calculation and to give practical trans mission coefficients which may be applied to various structures to deter mine the heat loss by direct transmission. The amount lost by air filtration is determined by different methods, as outlined in. Chapter 6, and must be added to that lost by direct transmission to obtain the total heating plant requirements. METHODS OF HEAT TRANSFER Heat transmission between the air on the two sides of a structure takes place by three methods, namely, radiation, convection and conduction. In a simple wall built up of two layers of homogeneous materials separated to give an air space between them, heat will be received from the high temperature surface by radiation, convection and conduction. It will then be conducted through the homogeneous- interior section by con duction and carried across to the opposite surface of the air space by radiation, conduction and convection. From here it will be. carried by conduction through to the outer surface and leave the outer surface by radiation, convection and conduction. The process of heat transfer through a built-up wall section is complicated in theory, but in practice it is simplified by dividing a wall into its component parts and considering the transmission through each part separately. Thus the average wall may be divided into external surfaces, homogeneous materials and interior air spaces. Practical heat transmission coefficients may be derived which will give the total heat transferred by radiation, conduction and convec tion through any of these component parts and if the selection-and method of applying these individual coefficients is thoroughly understood it is usually a comparatively simple. matter to calculate the over-all heat transmission coefficient for any combination of materials. . 85 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 HEAT TRANSFER COEFFICIENTS The symbols representing the various coefficients of heat transmission and their definitions are as follows: U thermal transmittance or over-all coefficient of heat transmission; the amount of . heat expressed in Btu transmitted in one hour per square foot of the wall, floor, roof or ceiling for a difference in temperature of 1 deg F between the air on the inside and that on the outside of the wall, floor, roof or ceiling. k -- thermal conductivity; the amount of heat expressed in Btu transmitted in one hour through 1 sq ft of a homogeneous material 1 in. thick for a difference in temperature of 1 deg F between the two surfaces of the material. The conductivity of any material depends on the structure of the material and its density. Heavy or dense materials, the weight of which per cubic foot is high, usually transmit more heat than light or less dense materials, the weight of which per cubic foot is low. C = thermal conductance; the amount of heat expressed in Btu transmitted in one hour through 1 sq ft of a non-homogeneous material for the thickness or type under consideration for a difference in temperature of 1 deg F between the two surfaces of the material. Conductance is usually used to designate the heat transmitted through such heterogeneous materials as plasterboard and hollow clay tile. / = film or surface conductance; the amount of heat expressed in Btu transmitted by radiation, conduction and convection from-a surface to the air surrounding it, or vice versa, in one hour per square foot of the surface for a difference in temperature of 1 deg F between the surface and the surrounding air. To differentiate between inside and outside wall (or floor, roof or ceiling) surfaces, /i is used to designate the inside film or surface conductance and f0 the outside film or surface conductance. '> a = thermal conductance of an air space; the amount of heat expressed in Btu trans mitted by radiation, conduction and convection in one hour through an area of 1 sq ft of an air space for a temperature difference of 1 deg F. The conductance of an air space depends on the mean absolute temperature, the width, the position and the character of , the materials enclosing it. R -- resistance or resistivity which is the reciprocal of transmission, conductance, or conductivity, i.e.: = over-all or air-to-air resistance. -p- = internal resistivity. -gr = internal resistance. -y- = film or surface resistance. --a-1-- .. = air space resistance. . ; ' As an example in the application of these coefficients assume a wall with over-all coefficient U. Then, ' where H = AU (l -- t0) (1) H = Btu per hour transmitted through the material of the wall, glass, roof or floor. A = area in square feet of wall, glass, roof, floor, or material, taken from building plans or actually measured. (Use the net inside or heated surface dimensions in all cases.) t -- t0 = temperature difference between inside and outside air, in which t must always be taken at the proper level. Note that t may not be the brealhing-line temperature in all cases. 86 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES If the heat transfer between the air and the inside surface of the wall is being considered, then, H = A fi (i - *,) (2) where fl = inside surface conductance. t and ti = the temperatures of the inside air and the inside surface of the wall re spectively. In practice it is usually the over-all heat transmission coefficient that is required. This may be determined by a test of the complete wall, or it may be obtained from the individual coefficients by calculation. The simplest method of combining the coefficients for the individual parts of the wall is to use the reciprocals of the coefficients and treat them as resistance units. The total over-all resistance of a wall is equal numeri cally to the sum of the resistances of the various parts, and the reciprocal of the over-all resistance is likewise the over-all heat transmission coef ficient of the wall. For a wall built up of a single homogeneous material of conductivity k and x inches thick the over-all resistance, (3) U If the coefficients fi, f0 and k, together with the thickness of the material x are known, the over-all coefficient U may be readily calculated as the reciprocal of the total heat resistance. For a compound wall built up of three homogeneous materials having conductivities klt k3 and k% and thicknesses xIt Xt and x3 respectively, and laid together without air spaces, the total resistance, _L = 1 xi | * , *> i 1 U /i 4, (4) For a wall with air space construction consisting of two homogeneous materials of thicknesses *1 and :2, and conductivities ki and k3, respectively, separated to form an air space of conductance a, the over-all resistance, --V = --fi +^ ^kt ++ --a +^ -k5, -++ --f0 (5) Likewise any combination of homogeneous materials and air spaces can be put into the wall and the over-all resistance of the combination may be calculated by adding the resistances of the individual sections of the wall. In certain special forms of construction such as tile with irregular air spaces it is necessary to consider the conductance C of the unit as built instead of the unit conductivity k, and the resistance of the section is equal to The method of calculating the over-all heat transmission coefficient for a given wall is comparatively simple, but the selection o^; the proper coefficients is often complicated. In some cases the constfne(j tion of the wall is such that the substituting of coefficients in the ap/ference formula will give erroneous results. This is the case with irregy'ancl con. ' 87 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES It out air spaces in concrete and tile blocks, and walls in which there are parallel paths for heat flow through materials having different heat resistances. In such cases it is necessary to resort to test methods to check the calculations, and in practically all cases it has been necessary to determine fundamental coefficients by test methods. Conductivity of Homogeneous Materials The thermal conductivity of homogeneous materials is affected by several factors. Among these are the density of the material, the amount of moisture present', the mean temperature at which the coefficient is determined, and for fiberous materials the arrangement of fiber in the material. There are many fiberous materials used in building construc tion and considered as homogeneous for the purpose of calculation, whereas they are not really homogeneous but are merely considered so as a matter of convenience. In general, the thermal conductivity of a material increases directly with the density of the material, increases with the amount of moisture present, and increases with the mean temperature at which the coefficient is determined. The rate of increase for these various factors is not the same for all materials, and in assigning proper coef ficients one should make certain that they apply for the conditions under which the material is to be used in a wall. Failure to do this may result in serious errors in the final coefficients. aluminum foil with low emissivity coefficients were substituted, a large part of the radiant heat would be eliminated. This would reduce the total coefficient for all wind velocities by about 0.7 Btu and would make but very little difference for the higher wind velocities. In many cases in building construction the heat resistance of the internal parts of the wall is high as compared with the surface resistance and the surface factors become of small importance. In other cases such as single glass windows the surface resistances constitute practically the entire resistance of the structure, and therefore become important factors. Due to the wide variation in surface coefficients for different conditions their selection for Surface Conductance Coefficients Heat is transmitted to or from the surface of a wall by a combination of radiation, convection and conduction. The coefficient will be effected, by any factor which has an influence on any one of these three methods of transfer. The amount of heat by radiation is controlled by the character of the surface and the temperature difference between it and the sur rounding objects. The amount of heat by conduction and convection is controlled largely by the roughness of the surface, by the air movement Over the surface and by the temperature difference between the air and the surface. Because of these variables the surface coefficients may be subject to wjde fluctuations for different materials and different con ditions. The inside and outside coefficients f\ and fa are in general affected to the same extent by these various factors arid test coefficients deter? iriined for inside surfaces will apply equally well to outside surfaces under^ like conditions. Values for /j in still and moving air at different mean , temperatures have been determined for various building materials at the University of Minnesota under a cooperative agreement with the Society.1 ' The relation obtained between surface conductances for differentmaterials at mean temperatures of 20 F is shown in Fig. 1. These values were obtained with air flow parallel to the surface and from other tests in which the angle of incident between the direction of air flow and the surface was varied from zero to 90 deg it would appear that these values might be lowered approximately 15 per cent for average conditions. While for average building materials there is a difference due to mean temperature, the greatest variation in these coefficients is caused by the Tiaracter of the surface and the wind velocity. If other surfaces, such as t -- to J.V.E. Research Report No. 869--Surface Conductances as Affected by Air Velocity, Tempera ' iracter of Surface, by F. B. Rowley, A. B. Algren and J. L. Blackshaw (A.S.H.V.E. Transac- ^,1930. p. 429). Fig. 1. Curves Showing Relation Between Surface Conductances for ; . Different Surfaces at 20 F Mean Temperature . a practical building becomes a matter of judgment. In calculating the, over-all coefficients for the walls of Tables 3 to 12, 1.65 has been selected as an average inside coefficient and 6.0 as an average outside coefficient for a 15-mile wind velocity. In special cases where surface coefficients become important factors in the over-all rate of heat transfer more selective coefficients may be required. Air Space Conductance . Heat js conducted across an air space by a combination of radiation, conduction and convection. The amount of heat by radiation is governed largely by the nature of the surface and the temperature difference between the boundary surfaces of the. air space. Conduction and con-- 88 89 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 vection are controlled largely by the width and shape of the air space and the roughness of the boundary surfaces. The thermal resistances of air spaces bounded by extended parallel surfaces perpendicular to the direction of heat flow and at different mean temperatures have been determined for average building materials at the University of Minnesota in a cooperative research program with the Society. The values given in Table 1 show the results of this study and apply to air spaces bounded by such materials as paper, wood, plaster, etc., having emissivity coefficients of 0.8 or higher. The conductivity coef ficients decrease with air space width until a width of about % in. has been reached, after which the width has but very little effect. In these Table 1. Conductances of Air Spaces* at Various Mean Temperatures Mean Text Dm Fahb 0.128 Conductances or Air Spaces fob Various Widths in Inches 0.250 0.564 0.493 0.713 1.00 1.500 20 2.300 1.370 1.180 1.100 1.040 1.030 1.022 30 2.385 1.425 1.234 1.148 1.080 1.070 1.065 40 2.470 1.480 1.288 1.193 1.125 1.112 1.105 so 2.560 1.535 1.340 1.242 1.168 1.152 1.149 60 2.650 1.590 T.390 1.295 1.210 1.195 1.188 70 2.730 1.648 1.440 1.340 1.250 1.240 1.228 80 2.819 1.702 1.492 1.390 1.295 1.280 1.270 90 2.908 1.757 1.547 1.433 1.340 1.320 1.310 100 2.990 1.813 1.600 1.486 1.380 1.362 1.350 110 3.078 1.870 1.650 1.534 1.425 1.402 1.392 120 3.167 1.928 1.700 1.580 1.467 1.445 1.435 130 3.250 1.980 1.750 1.630 1.510 1.485 1.475 140 3.340 2.035 1.800 1.680 1.550 1.530 1.519 ISO 3.425 2.090 1.852 1.728 1.592 1.569 1.559 Thermal Resistance of Air Spaces by F. B. Rowley and A. B. Algren (A.S.H.V.E. Transactions, Vol. 35,1929, p. 165), coefficients radiation is a large factor, and if surfaces with low emissivity coefficients are substituted for ordinary building materials the total amount of radiant heat will be reduced. The reduction in radiant heat caused by the low emissivity surface is independent of width of air space. i Air spaces properly formed in combination with metallic surfaces such as ' aluminum foil, coated sheet steel, and other materials having a reflective surface, possess heat repelling characteristics. Values of air spaces lined with aluminum foil on one or both sides for widths of in. and % in. are shown in Table 2 of conductivities. A low emissivity coefficient is dependent on the permanency of the reflective surface but the reports of several investigators2 have not established a basis for judging the effect of dust film, discoloration, corrosion, etc. While the information as to the permanence of reflective, surfaces under various conditions of use is limited, the appearance of the surface is not always considered a reliable guide to its insulating value. 'Aluminum Foil Insulation (National Bureau of Standards Letter Circular No. LC535. October 15. 1938). Some Reflective and Radiation Characteristics of Aluminum, by C. S. Taylor and J. D. Edwards (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, January, 1939, p. 59). ' 90 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES In comparing the conductance coefficients for air spaces with and with out bright metallic surface lining it should be noted that the reduction in heat transfer is substantially as great when one surface is lined as it is when both surfaces are lined. The reason for this is that practically 95 per cent of the total radiant heat is intercepted by one surface lining and there is but a limited amount left to be stopped by the second surface lining. The effect of any low emissivity surface in stopping the trans mission of radiant heat is the same regardless of whether it is on the high or low temperature side of the air space. For materials such as aluminum paint or bronze paint which stop a limited percentage of radiant heat there is a greater percentage of gain by addition of a second surface lining. PRACTICAL COEFFICIENTS For practical purposes it is necessary to have average coefficients that may be applied to various materials and types of construction without the necessity of making tests on the individual material or combination of materials. In Table 2 coefficients are given for a group of materials which have been selected from various sources. Wherever possible the proper ties of material and conditions of tests are given. However, in selecting and applying these values to any construction a reasonable amount of caution is necessary; variations will be found in the coefficients for the same materials, which may be partly due to different test methods used, but which are largely due to variations in materials. The recommended coefficients which have been used for the calculation of over-all coefficients as given in Tables 3 to 12 are marked by an asterisk. It should be recognized in these tables of calculated coefficients that space limitations will not permit the inclusion of all the combinations of materials that are used in building construction and the varied applications of insulating materials to these constructions. Typical examples are given of combinations frequently used, but any special construction not given in Tables 3 to 12 can generally be computed by using the conductivity values given in Table 2 and the fundamental heat transfer formulae. For example, the tabulation of all of the values for multiple layers of insulating materials would present extensive and detailed problems of calculations for the varied application combinations, but the engineer having the fundamental conductivity values can quickly obtain the proper coefficients. Attention is called to the fact that the conductivity values per inch of thickness do not afford a true basis for comparison between insulating materials as applied, although they are frequently used for that purpose. The value of an insulating material is measured in terms of its heat resistance, which not only depends upon the thermal conductivity coef ficient per inch but also upon the thickness as installed and the manner of installation. For instance the material having a coefficient of 0.50 and 1 in. thick is equal in value to a material having a coefficient of 0.25 and a thickness of Yi in. Certain types of blanket installations are designed to be installed between the studs of a frame building in such manner as to give two air spaces. In order to get the full value of such materials they should be so installed that each air space is approximately 1 in. or more in thickness and the air spaces should be sealed at the top and bottom to prevent the circulation of air from one space to the other. Another 91 0- HEATING VENTILATING AIR CONDITIONING GUIDE 1940 common error in installing such a material is to nail the blanket on the outside of the studs underneath the sheathing, in which case one air space is lost and also the thickness of the insulating material is materially reduced at the studs. There are certain other types of insulation which are very porous, allowing air circulation within the material if not properly installed. The architect or engineer must carefully evaluate the economic considerations involved in the selection of an insulating material as adapted to various building constructions. Lack of good judgment in the intelligent choice of an insulating material, or its improper installation, frequently represents the difference between good or unsatisfactory results. F . 2.ig Permissible Relative Humidities for Various Transmission Coefficients CONDENSATION IN BUILDINGS The water vapor, or moisture mixed with the air in buildings will be transmitted through many types of building construction if there is a; difference in the vapor pressures on. the two sides of the structure. Such water vapor will also condense whenever it comes in contact with surfaces or objects at or below the dew-point temperature. Thus two types of condensation. problems are encountered in building practice, namely' (1) Surface condensation or condensation on the interior building surfaces including the walls, ceiling, (or roof) and glass, and (2) Interstitial coni, densalion or the transmittance of the vapor through the building materials, and condensation of the moisture on surfaces or voids within the materials of construction. ' Condensation within the construction as well as condensation on the interior surfaces does not necessarily occur in all buildings but only in isolated cases when conditions conducive to such condensation exist. The 92 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES probability of condensation increases with the relative humidity or vapor pressure and with the temperature difference and, in the case of inter stitial condensation, decreases with the vapor resistance on the warm side of the wall. Condensation on interior building surfaces3 (surface condensation) may be eliminated by either reducing the relative humidity or by maintaining the interior surfaces at or above the dew-point temperature. Permissible relative humidities for various wall, roof or glass coefficients and tempera ture differences may be determined from Fig. 2. The permissible relative humidity for any specific type of construction may be determined by first ascertaining the coefficient of transmission (U) of the construction and then locating this coefficient on the horizontal scale of Fig. 2. A vertical line drawn to the proper outside temperature curve and then to the left hand scale will indicate the permissible relative humidity for the conditions involved. The dotted line shown in Fig. 2 indicates the per missible relative humidity (64 per cent) if surface condensation is to be avoided, for a frame wall having a coefficient of 0.26 and for an outside temperature of -- 10 F. Condensation within the construction may likewise be prevented by eliminating the moisture at the source or by providing a barrier on the warm side of the insulation construction. A good vapor barrier con struction may be obtained with a vapor-proof paper properly applied under the plaster or a vapor-proof finish on the interior surface of the wall4. In the case of attics, the greater the heat resistance in the top floor ceiling, the lower the attic temperature and consequently the greater the tendency for condensation to take place on the under side of the roof boards which moisture will drop on to the ceiling. Thus where thick insulations are installed between ceiling joists, it is desirable to allow openings for outside air circulation through attic space as a precaution against condensation on the underside of the roof even though barriers are used, in the ceiling below. Computed Transmission Coefficients Computed heat transmission coefficients of many common types of building construction are given in Tables 3 to 13, inclusive, each con struction being identified by a serial number. For example, the coefficient of transmission (17) of an 8-in. brick wall and in. of plaster is 0.46, and the number assigned to a wall of this construction is 1-B, Table 3. Example 1. Calculate the coefficient of transmission (U) of an 8-in. brick wall with H in. of plaster applied directly to the interior surface, based on an outside wind exposure . of 15 mph. It is assumed that the outside course is of hard (high density) brick having a conductivity of 9.20, and that the inside course is of common (low density) brick having a conductivity of 5.0, the thicknesses each being 4 in. The conductivity of the plaster is assumed to be 3.3, and the inside and outside surface coefficients are assumed to average 1.65 and 6.00, respectively, for still air and a 15 mph wind velocity. Solution, k (hard high density brick) = 9.20; x = 4.0 in.; k (common low density brick) = 5.0; x = 4.0 in.; k (plaster) = 3.3; x = l/2 in.;/i = 1.65;/0 = 6.0. Therefore, Permissible Relative Humidities in Humidified Buildings, by Paul D. Close (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, December, 1939). . `Condensation within Walls, by F. B. Rowley, A. B. Algren and C. E. Lund (A.S.H.V.E. Transactions. Vol. 44. I93S, p. 93). 93 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulators* The coeffiicierUs are expressed in Bin per hour per square foot per degree Fahrenheit per 1 in. thickness unless otherwise indicated. Material Description 5? G -l* Ho OD MASONRY MATERIALS Bates------------------- ---- Brickwork_____ Cement MobtaRCONCRETE_______ Stone.. Stucco. Td.f,__ Tile or Terra zzo_____ Low density-....... ............ High density----------------- Adobe.------.------------------Damp or wet___ ________ Typical.----------------------- Typical________________ Various ages and mixes4. Cellular-------------------------.------------------------- Cellular---- Cellular--------------------------------------------------- Cellular___ - Typical fiber gypsum, 87.5% gypsum and 12.5% wood chips Special concrete made with an aggregate of hardened clay--1-2-3 ___________ Sand and gravel,------------------------------------- Limestone.... _______ __ ... -------------- Cinder... ...... .......... ..................--.........-- Burned clay aggregate------------------------:------ Blast furnace slag aggregate---------------- -- Typical Typiftftl ---- ......... -------------------------------- Typical hollow clay (4 in.)--____ __________ Typical hollow clay (6 in.)4----------------____ Typical hollow clay (8 in.)*----------- i----------- Typical hollow clay (10 in.)* Typical hollow clay (12 in.)*---------------------- Typical hollow clay (16 in.)*--______ -- Hollow clay (2 in.) K*jn- plaster both sides~ Hollow clay (4 in.) H-ln. plaster both aides.. Hollow clay (6 in.) ^4*in. plaster both sides. Hollow gypsum (4 in.)----------------------------- Solid gypsum-------------------------------------------- Solid gypsum--_______ Typical flooring!---------------------------------------- 40.0 50.0 60.0 70.0 51.2 101.0 142.0 132.0 97.0 75.0 76.0 120.0 127.0 124.3 51.8 75.6 75 75 75 75' 74 70 75 75 75 75 70 no 100 105 "70 76 5.00* 9.20* 3.56* 5.00* 12.00* 12.00* 11.35 to 16.36 1.06 1.44 1.80 2.18 1.66* 3.98 12.6 10.8 4.9 4.0 1.6 12.50* 12,00* l.OOt* 0.64f* 0.60f 0.58f* 0.40f* 0,31f l.OOt 0.60f 0.47t 0.46t* 1.66 2.96 12.00* 0.20 0.11 0.28 0.20 0.08 0.08 0.94 0,69 0.56 0.46 0.60 0.25 0.08 0.09 0.22 0.25 0.63 0.08 0.08 1.00 1.57 1.67 1.72 2.50 3.23 1.00 1.67 2.13 2.18 0.60 0.34 0.08 (2) Authorities: Hj. S. Bureau of Standards, tests based on samples submitted by manufacturers. *A. C. Willard, L. C. Llchty, and L. A. Harding, tests conducted at the University of Illinois. *J. C. Peebles, tests conducted at Armour Institute of Technology, based on samples submitted by manufacturers. .. v ... , 4F. B. Rowley, tests conducted at the University.of Minnesota. ' A.S.H.V.E. Research Laboratory. . E. A. Allcut. tests conducted at the University of Toronto. . rLees and Charlton. . N- *G. B. Wilkes and C. M. F. Peterson, tests conducted at the Massachusetts Institute of Technology. Recommended conductivities and conductances for computing heat transmission coefficients. tFor thfcknesq stated or used on construction, not per 1 in. thickness. . For additional conductivity data see Chapters 3 and 15, 1937 AS.R.Ed Data Book, 6If outside surface of block is painted with an impervious coat of paint, add 0.07 to resistance for sand and gravel blocks. Add 0.18 to resistance for cinder blocks. Add 0.17 to resistance for burned clay aggre gate blocks. *. `Recommended value. See Heating, Ventilating and Air Conditioning, by Hardingand Willard, revised ^4See A^S.H.V.E. Research Report No. 915--Conductivity of Concrete, by F. C. Houghten and Carl Gutberlet (A.S.H.V.E. Transactions, VoL 38, 1932, p. 47). The 6-in., JLin., and 10-in. hollow tile figures are based on two cells in the direction of heat flow. The 12-in. hollow tile is based on three cells in the direction of heat flow. The 16-in. hollow tile consists of one 10-in. and one 6-in. tile, each having two cells in the.direction of heat flow.. . /Not compressed. . Roofing. 0.15-in. thick (1.34 lb per sq ft), covered with gravel (0.83 lb per sq ft), combined thickness aSS*Vahies for air spaces or surfaces having an effective emissivity of e = 0.S3 and for a temperature differ ence of 15 F. -- Values for air spaces or surfaces having an effective emissivity of e = 0.05 and for a temperature differ ence of 15 F. . . CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulators*--Continued The coefficients are expressed in Bin per hour per square foot per degree Fahrenheit per 1 in. thickness - unless otherwise indicated. 95 , HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Conductivities (k) and Conductances (C) or Building Materials and Insulators3--Continued The coefficients are expressed in Btu per hour per square foot per degree Fahrenheit per 1 in. thickness _______________________ unless otherwise indicated. Material Description D o SCE5* a--Hu. S3. Sg n Sq S iI eD seD gg -e o OO 1T ig &1 IN8ULATION--BLANKET OR FLEXIBLE TYPES INSULATION-SEMIRIGID TYPE INSULATION-LOOSE FILL OR BAT TYPE Fideb__ . 1_Glass Wool_____ b_Granule For notes see Page 94. Chemically treated wood fibers held between layers of strong paper/ Eel gra*ss betwaeen stromng p- apmer/------------- _ Fbx fibers between strong paper/ Chemically treated hog hair between kraft paper/. .................................. . Chemically treated hog hair between kraft paper and asbestos paper/....... ............... Hair felt between layers of paper/.................. Kapok between burlap or paper/ Jute fiber/..............- . ____________ Ground paper between two Uyera, each H-n. thick made up of two layers of kraft paper (sample HAn. thick)- Stitched and creped expanding fibrous blanket-- . Paper and asbestos fiber with emulsified asphalt binder _______ . 3.67 4.60 3.40 4.90 5.76 7.70 11.00 1.00 6.70 12.1 1.50 4.2 70 0.25 90 0.26 90 0.25 90 0.28 71 0.26 71 0.28 75 0.25 90 0.24 75 0.25 75 0.40f 70 0.27 94 0.28 Flax/ Rax and rye/ Felted bear and asbestos/-........................... 75% hair and 25% jute/ 50% hair and 50% Jute/ Jute/._...................... , Felted jute and asbestos/___ .. Compressed peat moss---- --__________ 13.00 11.00 12.10 13.60 7.80 6.30 6.10 6.70 10.00 11.00 90 90 70 90 90 90 90 75 90 70 0.26 0.30 0.32 0.28 0.27 0.26 0.25 0.37 0.26 aa a a Fibrous material made from dolomite and silica................ .... .... ........ Fibrous material made from slag. - Redwood bark ___ Redwood hark..--.... '* Fibrous material 25 to 30 microns in dia- meter, made from virgin bottle glass-------- Made from combined ailicatp of lime and alumina.................................................. ...... Made from expanded aluminum-magnesium silicate____ e a aa Flaked, dry and fluffy/___ a a* a* a a a aaa a aaa Rock wool with a binding agent................ Rock wool with flax, straw pulp, and binder Rock wool with vegetable fibers--_________ 1.90 1.60 75 75 1.50 9.40 3.00 5.00 1.50 75 103 90 75 `75 4.20 72 6.32 30.00 24.00 18.00 12.00 34.00 26.00 24.00 19.80 18.00 86 90 90 90 90 90 90 75 90 75 8.10 21.00 18.00 14.00 10.00 14.50 |14.50 11.50 90 90 90 90 90 77 75 72 0.23 0.24 0.27 0.27 0.31 0.26 0.27 0.24 0.29 1.00 0.77 0.59 0.44 0.60 0.52 0.48* 0.35 0.34 0.27* 0.31 0.30 0.29 0.28 0.27* 0.33 0.38 0.31 96 3.70 4.00 3.85 4.00 3.57 3.85 3.57 4.00 4.17 4.00 (3) > (!) (1) (3) (3) (3) Id (3) 2.50 3.70 3.57 (4) (3) a) 3.84 3.33 3.12 3.57 3.70 3.85 4.00 2.70 3.84 m ((30) (l) n u> (3) Cl) (3) 4.17 (3) (3) 3.70 (3) (1)3.70 . (1) 3.22 3.84 (3) 3.70 (3) 4.17 (3) 3.45 1.00 1.30 1.69 2.27 1.67 1.92 2.08 2.86 2.94 3.33 3.45 3.57 3.70 3.03 2.63 3.22' (((31O>)) (1) (1) (((11I))) (3) <(f1l)) (11)) (3) (3) Actboritt | Autboritt | CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulators3--Continued The coefficients are expressed in Btu per hour per square foot per degree Fahrenheit-per 1 in. thickness ' unless otherwise indicated. ' Material Description- ... ss D is i To tE ta g* 1 1Se ii 8 >S5 gB oo ei 88 Eo| BffiULATION-LOOSE FILL OR BAT TYPE .--Continued From maple. Beech and birch (coarse)______ 12.00. 90 8.80 ` 90 13.20 - 90 0.41 0.41 0.36 2.44 2.44 2.78 INSULATION-RIGID aa aa aa a a a ' . ` . . 90 7.00 90 90 14.50 90 Fnifrr Chemically treated hog hair covered with 75 5 71 78 70 Insulating plaster 9/10 in. thick applied to 75 81 B * 85% magnesia and 15% asbestos 19.30 86 * * shredded wood and cement-.-.... 24.20 72 13.50 70 * ', " ; i . . Sugar cane fiber insulation blocks encased in . 13.80 70 17.00 - 68 72 :a a aa aa aa - ' 15.00 70 ' 52 8.50 72 15.20 16.90 90 0.30* 0.34 0.30 0.27 0.25. 0.32 0.33* ` 3.33 2.94 3.33 3.70 4.00 3.12 3.0J 0.28 0.33 0.32 0.32 3.57 3.03 3.12 3.12 1.07f 0.93 0.34 2.94 0.51. .. 1.96 0.46 2.17 0.33 3.03 0.30 0.33 0.33 0.33 0.33 0.29 0.33 0.34 3.33 3.03 3.03 3.03 3.03 3.45 3.03 2.94 BUILDING BOARDS ' Asbestos__________________ Gtfbum___ ' Compressed cement and asbestos sheets-------- 123.00' Gypsum between layers of heavy paper_____ 62.80 Rigid, gypsum between byera" of heavy 53.50 Gypsum mixed with sawdust between layers (U in 7 * `. ' ' . 60.70 (M in.) 86 110 86 70 90 90 S'2.70 ` 0.37 0.48 2.08 0.84 1.19 1.41 0.71 2.60f 0.38 3.607 0.28 3.73f* 0.27 2.82f* ' 0.35 ROOFING CONSTRUCTION 70.00 ' 75 Built up, bitumen and felt, gravel or slag Plasterboard, gypsum fiber concrete and Wftnri 52.40 65.00 70.00 201.00 76 75 75 6.50f* 0.15 3.53f* 0.28 1.33 0.75 0.58f 6.00f* 6.50f* . 10.37* ' 1.28t* 1.72 0.17 0.15 0.10 0.78 PLA8TERING MATERIALS Gypsum and expanded aluminum-magne- Wood Lath awd Plasteb____ H in- piaster, total thickness *4" in........ - -- For notes see Page 94. 97 39.9 -- ' 75 73 70 8.00 3.30* 0.85 8.80| 4.40f* 2.50f* 0.13 0.30 1.18 0.11 0.23 0.40 (I) (1) (I) (1) (1) (1) (1) (1) (3) (3) (4) (3) (3) 13) (i) (3) (3) (3) (3) (3) (3) (6) 3) 3) (1) (1) (2) (1) <3) (1) (ii (3) (2) (4) (3) h(3) (2) (3) (4) (4) HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulators8--Continued The coefficients are expressed in Btu Per hour per square foot per degree Fahrenheit per l * thickness Material , Description 33 CI s J! 1c 15 s 6 g 5 i ip p 1 g s IS R 5 6 oo 1 1 BUILDING CONSTRUCTIONS 1-in. fir sheathing and building paper-----------r 1-in. fir sheathing, building paper, and 1-in. fir whftathing, buying paper and stucco Pine lap siding and building paper--siding ---- 40.00 Battleship linoleum 04 in.)-------- ---------- -- ------- 30 20 20 16 -- 75 air space and surface COEFFICIENTS Over H in- faced ordinary building materials 3J4 in. Reed ordinary building materials Horizontal, heat flow upward, e *= 0.83 -- -- Horizontal, heat flow downward, t =_ 0.83* " 354 1* faced reflective building materials Horizontal, heat flow upward, e =* 0.05*-- Horizontal, heat flow downward, e = 0.05* ------- Horizontal, heat flow upward, e 0.83(/i)fc -- Horizontal, heat flow downward, * m rt Surface, ReflectiveTM----- Still air (/), AvgTM-------------- --- , ,,./vrr Horizontal, heat flow upward, e * U.UiUu* Vertical, e = O.OSf/i)4------------ ---------------' Horizontal, heat flow downward. . e =. 0.05(/0*__ ___ _________ ______ t . --. Am SPACES PACED WITH Air space, laced one side with bright ahimi- FOIL Air space, faced one side with bright alusu- Air space, faced both sides with bright Air space, faced bote sides with bright AiT space divided in two with angle curtain of bright aluminum foil (both sides bright) Air space with multiple curtains of bright aluminum foil, bright on both sides, curtains more than J4 in. apart sir circu lation between spaces prevented*. 4 curtains, forming 5 spaces,.... .................. i. -- SPACES FACED WITH NON- Fabric with non-metaliic reflective surface METALLIC PAINT (16 in. thick) placed in center of a 1H in. SURFACE Core of fiber board coated two sides with non-metaliic reflective surface (54 m- thick) placed in space having approxi mately 54 in. air space on each ode-------- Fiber board coated one side with non- metaliic reflective surface (54 m*. thick) placed in space having approximately 23.4 40 - -- --* _ -- - 50 50 50 50 50 50 50 50 50 70 70 75 0.86f* 0.50t* 0.82 0.85f* 1.28f 1.20 1.36f* 1.16 2.00 1.22 1.18 0.83 0.74 ( s (4) (4) ( 1-lOf 1.32 1.17 0.94 0.56 0.41 0.17 1.651* 1.95t l.SZf l.ilf 6.00f* 9.00t 0.807* 1.167 0.74f 0.44f 0.91 0176 0.86 1.79 2.44 5.88 0.61 0.66 0.83 0.86 1.35 2.27 (4) (8) I (8) 8) (8) (4) (8) (8> w m (8) (8) 0.46f 0.62f 0.41f 0.577 2.17 1.61 2.44 1.75 (4) (4) (4) (4) 0.237* 4.35 0,317 3.23 ( (4) 0-lSf* o.llt* 0.097* 6.78 ' 9.22 11.66 (4) (4) (4) 0.337 3.03 (3) 0.27t 3.70 (3) 0.49t 2.04 (3) For cotes see Page 94. A c tb o b itt | Autboritt CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Table 2. Conductivities (k) and Conductances (C) of Building Materials and Insulators3--Continued The coefficients are expressed in Btu per hour per square foot per degree Fahrenheit per 1 in. thickness unless otherwise indicated. Material Description tuo D IaM o, u S A. ia QS SPACES FACED WITH NON- Air space divided in two with fabric faced METALLIC PAINT bout sides with non-metaliic reflective SURFACE--(Continued) Air space over in- wide faced one side with non-metaliic reflective surface._______ ___ WOODS (Across Grain) DaiaA------ California Redwood------ * 169r 1697 0 * rDuuuLAS . Eastbbn Hemlock_________ Hzan Mafle------------------ --- r 11669?3_ t i f,b> . 1697 Lokoleaf Yellow Pine____ 169_ 16 169 169 . _ , * 0 0 4 M 0 4 _ 16^_ 169. _ 1166^97_ . 116699._ S&obtleaf Yellow Pine___ 169l m. 4 0 0 0 0 0 0 0 * 16<V . 169_ . 169,, 16J . 169_ 165 West Coast Hemlock______ White Pin* 116699' Yellow Pine ob Fm For notes.see Page 94. 0 0 0 0 0 0 on 20.0 8.8 7.3 22.0 28.0 28.0 28.7 26.0 34.0 34.0 22.0 30.0 22.0 30.0 40.0 46.0 30.0 30.0 34.3 44.3 22.0 32.0 22.0 22.0 32.0 48.0 38.0 43.0 36.0 26.0 36.0 28.0 34.0 28.0 36.0 42.0 36.0 42.0 28.0 22.0 28.0 34.3 22.0 30.0 22.0 30.0 31.2 ---- Si gf S3 3g SB 3S * R Ee DD gg OO ou ~l-" ^ ee t3 Sg 11 40 0.33f 3.03 (4) 40 Q.67t 1.49 (4) 90 0.58 1.72 (1) 90 0.38 2.63 (1) 90 0.33 3.03 (1) 75 0.66 1.53 (4) 75 0.70 1.43 <4) 75 0.74 1.35 (4) 75 0.80 1.25 (4) 86 0.67 1.49 a) 75 0.61 1.64 (4) 75 0.67 1.49 (4) 75 0.76 1.32 (4) 75 0.82 1.22 14) 75 0.60 1.67 (4) 75 0.76 1.32 (4) 75 0.67 1.49 (4) 75 0.85 1.18 (4) 75 1.01 0.99 (4) 75 1.05 0.95 (4) 75 1.15 0.87 (4) 75 1.21 0.83 (4) 75 0.76 1.32 (4) 75 0.86 1.16 (4) 75 0.89 1.12 (4) 75 1.03 0.97 (4) 86 0.90 1.11 (1) 86 1.10 0.91 (i) 1.15* 0.87 75 0.62 1.61 (4) 75 0.74 1.35 (4) 75 0.74 1.35 (4) 75 0.91 1.10 (4) 75 0.67 1.49 (4) 75 0.79 1.27 (4) 75 0.74 1.35 (4) 75 0.90 1.11 (4) 75 0.98 1.02 14) 75 1.18 0.85 (4) 75 1.07 0.94 (4) 75 1.29 0.78 (4) 75 0.74 1.35 (4) 75 0.91 1.10 (4) 75 0.84 1.19 (41 75 1.04 0.96 (4) 75 0.73 1.37 (4) 75 0.88 1.14 (4) 75 0.81 1.24 (4) 75 0.97 75 0.89 1.03 (4) 1.12 (4) 75 0.95 1.05 (4) 75 1.01 0.99 (4) 75 1.09 0.92 (4) 75 0.54 1.85 (4) 75 0.64 1.56 (4) 75 0.65 1.54 (4) 75 0.78 1.28 (4) 86 0.96 1.04 (1) 75 0.68 75 0.79 1.47 (4> 1.27 4) 75 0.78 1.28 (4) 75 0.91 1.10 (4) 86 0.78 1.28 1.00 1.00 (3) -- 0.80* 1.25 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 3. Coefficients of Transmission (U) of Masonry Walls Coefficients ore expressed in Btu per hour per square foot per degree Fahrenheit difference in temperature between Ike air on the two sides, and are based on a wind velocity of 15 mph.. TYPICAL CONSTRUCTION TYPE OF WALL Tbicknsss or Masonbt (Inches) Wall No. Solid Brick Based on 4-in. hard brick and the remainder common brick. 8 12 16 1 2 3 Hollow Te Stucco Exterior Finish. The S-in. and 10-in. tile figures are based on two cells in the direction of flow of heat. The 12-in. tile is based on three cells in the direction of flow of heat. The 16-in. tile consists of one 10-in. tile and one 6-in. tile each having two cells in the direction-of heat flow. 8 10 12 16 4 5 6 7 Limestone or Sandstone 812 16 24 8 9 10 , 11 Concrete (Monolithic) - These figures may be used with sufficient accuracy for concrete walls with stucco exterior finish. * Cinder (Monolithic) Conductivity k 4.30 Burned Clay aggregate (Monolithic) Conductivity k ** 3.96 Cinder Blocks Cores filled with dry cinders, 69.7 lb per cu ft. Cores filled with granulated cork. 5.12 lb per cu ft. Cores filled with rock wool, 14.2 !b per cu ft. Based on one air cell in direction of heat flow. Cores filled with granulated cork, 5.24 lb per cu ft. Concrete Blocks Cores filled with granulated cork, 5.14 lb per Based on one air cell in direction of heat flow. Burned Clay aggregate Blocks Cores filled with granulated cork, 5.06 lb pe cu ft. Burned Clay aggregate Blocks : Cores filled with granulated cork, -5.6 lb pe r cu ft. Computed from factors marked by in Table 2. bBased on tbe actual thickness of in. furring strips. 100 6 10 16 20 6 10 16 20 6 10 16 20 8 8 8 8 12 12 8 8 12 8 8 12 12 12 13 14 15 16 17 19 20 21 23 24 25 - 26 27 28 29 30 31 32 33 34 35 36 Plain watts--no in terior finish Decorated building board 0 4 in.) with out plaster--furred Plaster (H in.) on metal lata attached to furring strips (2 in.6) -- flexible in sulation ( H in-) be tween furring strips (one air space) CHAPTER :5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Untnsulatbd Walls eO 1 aP a S|5 & sjl i i Jl 111 J=i Cu p .s PH 3 ABcD E INTERIOR FINISH Insulated Walls aO'---' 3slX 5.1 ixl '5.3w`22_ SJ$ii xi? ~o - s-s-sS *4isri r.sj-ii alb jcT l-T !i-5l4i Jl-i Ch`C.5 Sl-c.2 Essa .ESSJiXg-l sate ;if? Six E.2 F G II I J K L 0.46 0.30 0.32 0.30 *0.36 0.34 0.24 0.25 0.24 0.28 0.27 0.20 0.21 0.20 0.23 0.19 0.17 0.22 0.16 0.14 0.19 0.14 0.12 0.16 0.13 0.11 0.23 0.19 0.17 0.12 O.U 0.10 0.20 0.17 0.15 0.40 0.38 0.26 0.28 0.26 0.39 0.37 0.26 0.27 0.26 0.30 0.29 0.22 0.22 0.22 0.25 0.24 0.19 0.19 0.19 0.20 0.20 0.17 0.16 0.20 0.15 0.19 0.15 0.17 0.14 0.15 0.12 0.13 0.13 0.12 O.U 0.20 0.20 0.18 0.16 0.11 0.11 0.10 0.097 0.18 0.18 0.16 0.14 0.71 0.64 0.37 0.39 0.37 0.58 0.53 0.33 0.34 0.33 0.49 0.45 0.30 0.31 0.30 0.37 0.35 0.25 0.26 0.25 0.26 0.24 0.22 0.20 0.25 0.1S 0.23 0.17 0.22 0.16 0.19 0.15 0.15 0.14 0.14 0.13 0.26 0.24 0.22 0.20 0.13 0.13 0.12 0.11 0.23 0.21 0.20 0.18 0.79 0.70 0.39 0.42 0.39 0.62 0.57 0.34 0.37 0.34 0.48 0.44 0.29 0.31 0.29 0.41 0.39 0.27 0.28 0.27 0.27 0.25 0.22 0.21 0.26 0.19 0.24 0.18 0.21 0.16 0.20 0.15 0.16 0.15 0.14 0.13 0.27 0.25 0.22 0.21 0.13 0.13 0.12 0.12 0.23 0.22 0.20 0.18 0.46 0.43 0.29 0.30 0.29 0.33 0.31 0.23 0.24 -0.23 0.22 0.22 0.17 0.18 0.17 0.19 0.18 0.15 0.15 0.15 0.44 0.41 0.28 0.29 0.28 0.30 0.29 0.22 0.23 0.22 0.21 0.20 0.16 0.17 0.16 0.17 0.17 0.14 0.14 0.14 0.42 0.39 0.27 0.28 0.27 0.31 0.29 0.23 0.23 0.22 0.22 0.21 0.17 0.18 0.17 0.23 0.22 0.19 0.18 0.18 0.37 0.35 0.25 0.26 0.25 0.20 0.19 0.17 0.16 0.16 0.56 0.52 0.32 0.34 0.32 0.41 0.39 0.27 0.28 0.27 0.49 0.46 0.30 0.32 0.30 0.36 0.34 0.26 0.26 0.24 0.18 0.17 O.lo 0.15 0.14 0.34 0.32 0.25 0.25 0.24 0.15 0.14 0.13 0.13 0.12 0.22 0.18 0.15 0.13 0.21 0.17 0.14 0.12 0.21 0.18 0.14 0.15 0.19 0.13 0.24 0.21 0.23 0.19 0.13 0.19 0.11 0.21 0.16 0.18 0.14 0.14 0.12 0.13 0.11 0.14 0.12 0.10 0.09 0.21 0.16 0.17 0.14 0.14 0.11 0.12 0.10 0.13 0.12 0.10 0.09 0.20 0:16 0.13 0.17 0.14 0.12 0.14 0.12 0.11 0.14 0.12 0.10 0.19 0.15 0.13 0.13 0.11 0.10 0.23 0.17 O.H 0.20 0.15 0.13 0.22 0.16 0.14 0.19 0.15 0.13 0.12 0.10 0.09 0.18 0.14 0.12 0.11 0.09 0.08 0.22 0.18 0.15 0.13 0.21 0.18 0.14 0.12 0.21 0.18 0.14 0.15 0.19 0.14 0.24 0.21 0.23 0.19 0.13' 0.19 0.11 0.12 O.U 0.09 0.09 0.12 0.10 0.09 0.08 0.12 0.11 0.09 0.09 .0.11 0.09 0.12 0.12 .0.12 0.11 0.08 0.11 0.08 0.19 0.16 0.13 0.12 0.19 0.16 0.13 0.11 0.19 .0.10 0.13 0.14 0.17 0.13 0.21 0.18 0.20 0.17 0.12 0.17 0.10 A waterproof membrane should be provided between the outer material and the insulation. fill to prevent possible wetting by absorption and a subsequent lowering of efficiency. :, 101 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 4. Coefficients of Transmission (U) of Masonry Walls with Various Types of Veneers Coefficients are expressed in Btu per hour per sguarc foot per degree Fahrenheit difference in temperature between the air on the two stdes, and are based on a wind velocity of 15 mph. TYPICAL CONSTRUCTION TYPE OF WALL Facing Backing Wau, No. 4 in. Brick Veneer1 6 in. 8 in. 10 in. Hollow Tile* 12 in. 37 38 39 40 4 In. Brick Veneer- 6 in. 10 in. Concrete 16 in. 41 42 43 8 in. Cinder Blocks 8 in. Cinder Blocks -- Cores filled with granulated cork. 5.12 lb per cu ft. 12 in. Cinder Blocks 12 in. Cinder Blocks -- Cores filled with granulated cork. 5.24 lb per cu ft. 8 in. Concrete Blocks 8 in. Concrete Blocks--Cores filled with granulated cork, 5.14 lb per cu ft. 12 in. Concrete Blocks 8 in. Burned Clay aggregate Block 8 in. Burned Clay aggregate Block--Cores filled with gran ulated cork, 5.06 lb per cu ft. 12 in. Burned Clay aggregate Block 12 in. Burned Clay aggregate Block--Cores filled with gran ulated cork. 5.6 lb per cu ft. 44 45 46 47 48 49 50 51 52 53 54 4 in. Cut-Stone Veneer- 8 in. 12 in. Common Brick 16 in. 55 56 57 4 in. Cut-Stone Veneer- 6 in. 8 in. Hollow Tile* 10 in. 12 in. 58 59 60 61 4 in. Cut-Stone Veneer- 6 in. 10 in. Concrete 16 in. 62 63 64 Computed from factors marked by * in Table 2. ` ' kBased on the actual thickness of 2-in. furring strips. . - The 6-in.. 8-in. and 10-in. tile figures are based on two cells in the direction of heat flow. tile i9 based on three cells *u the direction of heat flow. T. The 12-m. CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES INTERIOR FINISH Uninsulated Walls Insulated Walls Plaster on wood lath--furred Plaster (V i Id.) on metal lath f--urred No plaster--deco rated rigid or build ing board interior finish (V i in.)-- furred blaster (V i in.) on rigid ioaulation (1 in.)--furred 1Plaster IM in.) on metal latn attached to furring s trip e - furred space (over V i in. wide) faced one side w ith bright aluminum foil .is c oa jS kX 3S 2-S j5l- fin * 5 gx 2s ao.-S-Sr--3g>3 WSil?i? fll 5J lI d m Isi sIbsS ABCD E F GH i J gl-tl Sw3dMod .--2.*"o5 i*s3ao 52/5 S..Js9 -hg--rXi ||- S ~ --3 3ti^n3-Ea*i ssI|ss--s3.Ss ss KL 0.36 0.34 6.34 0.27 0.34 0.33 0.32 0.26 0.24 0.24 0.23 0.20 0.25 0.25 0.24 0.21 0.24 0.24 0.23 0.20 0.19 0.19 0.19 0.16 0.19 0.18 0.18 0.16 0.15 0.14 0.14 0.13 0.13 0.12 0.12 0.11 0.19 0.19 0.19 0.16 0.11 0.11 0.11 0.10 0.17 0.17 0.17 0.15 0.57 0.53 0.33 0.35 0.33 0.48 0.45 0.30 0.31 0.30 0.39 0.37 0.26 0.27 0.26 0.24 0.22 0.20 0.23 0.17 0.22 0.16 0.19 0.15 0.14 0.14 0.13 0.35 0.33 0.24 Q.25 0.24 0.20 0.19 0.16 0.16 0.16 0.31 0.30 0.22 0.23 0.22 0.19 0.13 0.18 0.18 6.14 0.12 0.13 O.lt 0.10 0.17 0.14 0.12 0.18 0.18 0.15 0.15 0.15 0.44 0.42 0.28 0.30 0.28 0.13 0.21 0.12 0.10 0.21 0.16 0.09 0.13 0.34 0.32 0.24 0.25 0.23 0.40 0.38 0.26 0.28 0.26 0.31 0.29 0.23 0.23 0.22 0.19 0.20 0.18 0.18 0.14 0.20 0.15 6.17 0.14 0.12 0.13 0.12 0.17 0.16 0.14 0.14 0.14 0.29 0.28 0.21 0.22 0.21 0.12 0.17 0.12 0.10 0.17 0.13 0.09 0.12 0.14 0.14 0.12 0.12 0.12 0.10 0.10 0.09 0.08 0.37 0.35 0.25 0.26 0.25 0.28 0.27 0.21 0.21 0.21 0.23 0.22 0.18 0.18 0.18 0.19 0.17 0.15 6.19 0.15 0.16 0.13 0.12 0.13 0.12 0.11 0.24 0.22 0.20 0.19 0.13 0.18 0.13 0.21 0.19 0.20 0.18 0.12 0.17 0.10 0.19 0.17 0.15 0.13 0.12 0 11 0.11 0.09 0.11 0.08 0.12 0.11 0.11 0.11 0.08 . 0.10 0.07 0.11 0.10 0.095 0.21 0.20 o;i8 0.17 0.12 0.16 0.12 0.19 0.17 0.18 0.16 0.11 0.16 0.10 0.17 0.15 0.14 0.37 0.36 0.35 0.35 0.34 0.33 0.26 0.25 0.24 0.24 0.20 0.26 0.25 0.25 0.21 0.25 0.24 0.24 0.20 0.20 0.19 0.19 0.17 0.19 0.19 0.18 0.16 0.15 0.15 0,14 0.13 0.13 0.13 0.12 0.11 0.20 0.19 0.19 0.17 0.11 0.11 0.11 0.10 0.18 0.17 0.17 0.15 0.61 0.56 0.84 0.36 0.34 0.51 0.47 0.31 0.32 0.31 0.41 0.38 0.26 0.28 0.26 0.25 0.23 0.20 0.24 0.18 0.22 0.17 0.20 0.15 0.15 0.14 0.13 0.25 0.23 0.21 0.13 0.12 0.11 0.22 0.20 0.18 _ ------uawama vTa *u./ uciwccu vcucci or lacing auu pacKing. tfased on one air cell in direction of heat flow. A waterproof membrane should be provided between the outer material and the insulation fill to prevent possible wetting by absorption and a subsequent lowering of efficiency. ins HEATINC VENTILATING AIR CONDITIONING CUIDE .1940 Table 5. Coefficients of Transmission (U) of Various Types of Frame Construction0 These coefficients arc expressed in Btu Per hour per square foot Per degree Fahrenheit difference in temperature between the air on the-two sides, and are based on a wind velocity of 16 mph. TYPICAL CONSTRUCTION EXTERIOR FINISH TYPE OF SHEATHING Win, No. STWS 1 in. Wood' Wood Siding or Clapboard in. Rigid Insulation H In. Plasterboard .*"%! JCV/. Wood Shingles' 1 in. Wood' in. Rigid Insulation*' K In- Plasterboard* 66 67 70- .1- in. Wood' Stucco /TOPA bUCK.) in. Rigid Insulation H in. Plasterboard ,vf73v 1 in. Wood' 74 Brick/ Veneer Rigid Insulation /HtATHlN<r ^ in. Plasterboard 76 "Computed from factors marked by in Table-2. `These coefficients may also be used with sufficient accuracy for plaster on wood lath or plaster on plasterboard. : Based on the actual width of 2 by 4-in. studding, namely, 3% in. CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES INTERIOR FINISH No Insulation Between Studding Insulation Between Studding a0 a J3 '3 p 1 3 | a1 ao i a ao 1 ` ao u c --H3 1d ~3 S 0 5 1 ,, ca Sis %% 5w= fe d li a. P* a AB c 0.25 0.26 0.25 o .c0 - 3 9 J 39 a 9 0 a ;a -c i *3 'o "d Jj IX O 5 atc .?! s! 0 jf O.C- DE d s 1 j* 3 0s --d SI 3l |OhSO F 0.19 0.15 0.11 2> `3a--. A.*"O C xi -Vl II T! 3-B 11 OM 55.5 G & i W ll ,-g it la a 8 S.S .S ft H *0 3-S TS JS s 3* 1 - S*O d= ill iSu'" i 1 I Plaster in.) on metal lath6 on 1studding--flexible insolation (fa in.) J between studding and in contact with 1sheathing e-- 0d sss -- o* 2I-S si~ B-- I B SiM * - Sl| 111 Oh K L 0.19 0.17 0.19* 0.17 0.15 0.12 Plaster l}/{ in.) on metal lath6 on studding--flexible insulation (1 in.) between studding--2 air spaces 53 lx 3= *h "a7J|;5a sPr'Si "o 3^3 Jl| Oh b JS M 0.072 0.19 0.20 0.19 0.15 0.13 0.10 0.16 0.14 0.16 0.15 0.13 0.10 0.068 0.31 0.33 0.31 0.22 0.17 0.13 0.23 0.19 0.24 Q.20 0.17 0.13 0.076 0.25 0.26 0.25 0.19 0.15 0.11- 0.19 0.17 0.20 0.17 0.15 0.12 0.072 0.17 0.17 0.17 0.14 0.11 0.092 0.14 0.14 0.14 0.13 0.11 0.094 0.064 0.24 0.25 0.24 0.19 0.15 0.11 0.19 0.19 0.19 0.17 0.15 0.12 0.071 0.30 0.32 0.30 0.22 0.16 0.12 0.22 0.19 0.23 0.20. 0.17 0.13 0.076 0.22 0.23 0.22 0.17 0.14 0.11 0.19 0.15 0.18 0.16 0.14 0.11 0.071 0.40 0.43 0.40 0.26 0.19 0.14 0.28- 0.22 0.29 0.24 0.20 0.14 0.081 0.27 0.28 0.27 0.20 0.15 0.12 0.21 0.17; 0.21 0.18 0.16 0.12 0.074 0.21 0.21 0.21 0.16 0.14 0.10 . 0.17 0.15 0.17 0.15 0.13 0.11 0.068 0.35 0.37 0.35 0.24 0.18 0.13 0.25; 0.21; 0.26 0.22 0.18 0.14 0.079 'Yellow pine or fir--actual thickness about % in. ; Furring strips between wood shingles and sheathing. /Small air space and mortar between building paper and brick veneer neglected. .. waterproof membrane should be provided between the outer material and the insulation fill to 9 i!?t possible wetting by absorption and a subsequent lowering of efficiency. otud and rock wool fill areas combined. . - - HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Table 6. Coefficients of Transmission (U) of Frame Interior Walls and Partitions'1 Coefficients are expressed in Btu per hour per square foot per degree Fahrenheit difference in temperature between the air on the two sides, and are based on still air (no wind) conditions on both sides. TYPICAL CONSTRUCTION DOUBLE PARTITION (Finished on Both 8ides or Studding) SINGLE Partition Wall (Finish No. on One Air 8idb or Space Studding) Between Studding Flaked Gypsum Between Studding Rock Wool Fill* Between Studding H in. Flexible Insulation Between Studding (Oqc Air Stud Space Faced One Side with Bright Aluminum Foil Space) Type of Wall * Wood Lath and Plaster On Studding Metal Lath and Plaster* On Studding Plasterboard (H >n-) and Plaster' On Studding in. Rigid Insulation and Plaster' On Studding 1 in. Rigid Insulation and Plaster' On Studding in. Corkboard and Plaster' On Studding 2 in. Corkboard and Plaster' On Studding 77 78 79 80 81 82 83 A 0.62 B 0.34 C 0.11 0.69 0.39 0.11 0.61 0.34 0.10 0.35 0.18 0.083 0.23 0.12 0.066 0.16 0.081 0.052 0.12 0.063 0.045 D 0.076 0.078 0.075 0.063 0.054 0.044 0.038 E 0.21 0.23 0.21 0.14 0.097 0.070 0.057 F 0.24 " 0.26 0.24 0.15 0.10 0.073 0.059 Computed from factors marked by In Table 2. Thickness assumed 3% in. Plaster on metal lath assumed H in. thick. 'Plaster assumed H in* thick. Table 7. Coefficients of Transmission (U) of Masonry Partitions Coefficients are expressed in Btu per hour per square foot per degree Fahrenheit difference in temperature between the air on the two sides, and are based on still air (no wind) conditions on both sides. TYPICAL CONSTRUCTION No. Plain Walls (No Plaster) Walls Plastered on One Side Wails ; . Plastered on Both Sides : Type op Wall 4-In. Hollow Clay Tile 4-in. Common Brick 4-in. Hollow Gypsum Tile 2-in. Solid Plaster 84 [85 86 87 Computed from factors marked by in Table 2. 106 A 0.45 0.50 0.30 -- B 0.42 0.46 0.28 -- C 0.40 0.43 0.27 0.53, Table 8. Coefficients of T ransmission V ) of Frame Construction Floors and Ceilings0( Coefficients are expressed in B tu per hour per square foot per degree Fahrenheit difference in tem perature between the a ir on the two sides, and are based on s till a ir (no w in d ) conditions on both sides. T Y P IC A L CONSTRUCTION TYPE OF FLOORING " CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES '_ | 0.34 0.25 0.23 0.18 0.14 0.19 0.066 O.U 0.094 ssS .2f S=s S-g ag 3*11* .If si- Cd Q So a ,, 0* t&O'ss d.g Ila15g 'Sfa ~ O n || . 0.27 || . . 0.21 | 0.20 1 0.34 |[ 0.25 | 0.24 1 ' 24 | || . |. | | 0.16 0.13 | | 0.14 | o! C4 o QO t c*. od | 0.19 | | | 0.11 | 0.12 | - 0.081 | | || 0.066 | *U d | | 0.22 | 0.13 ' 0.086 | 0.068 0.46 0.30 0.28 0.28 0,21 Joists Yellow Pine Flooring^ on | sro i | 91 0 | || | | 0.69 0.62 0.61 0.23 0.59 0.17 0.079 0.16 No Flooring -< teoo o o o - to w to ts CO O' - | 180'0 | i 0.063 0.10 0.087 0.10 Tf<38l 2 o Vo 3 a ie> JV3 JVO 1 o ~V3>a H 1 None ' | . ......... | F le x ib le ' I n s u la t io n (2 in .) | | F le x ib le ' In s u la tio n (1 in .) | R ig id In s u la tio n (1 in .) a n d P la s te r ( H in .) |, N o n e | . None | None | . | None' ' ' j IN S U LA T IO N B E T W E E N JOISTS No. | None j1 N o n e . W ood L a th and P laster M e ta l L a th a n d P laster in.) a a5 i fa*as* 9 9 9 fa fl 9 fl a .s a5 X e o uo V 9 fl9 . *3 a A w<5 9 9 2 et' fa 2 M e ta l L a th and P laster | O fa a s 8 a 9 5 l) c a 107 M e ta l L a th and P laster ; M e ta l L a th and P laster M e ta l L a th a n d P laster . j G X CO a 1 13 PS c i u -& 9 9 fa o 'fl 9 G X uo 09 1 u C o rk b o a rd (2 in .) a n d P la s te r () in .) None C om puted fro m factors m arked b y * in .T a b le 2. Thickness assumed to be % in. Thickness assumed to be % in. . * s a E B T ype o f C e ilin g N o C e llin g . CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Cb S3 tn Z Uh > H >< zQ ioi. *B E-2 o02 eg o ;i g sk <2 !$>? O B'-' U -C k. lx. 5 5 w -*2 u. ** 3 oZ U S*>it*s) ^3 u. . V o s Zcn fict ss r st/> g: 2 fe 2J H5 a* o U OSo .f !*S *1*1 S *35=3 ,5 joseg g6 e|3 E-* a ,S Voi1a* X"0|0a0M5g,,. SfsE-gil pS|li5 ss S|2 ff|M lips *6aC0 * 8S Eg *lO*iOCO^ TjveCo5 oooo oo NNH 28 5* g0 aa * CS.C 2*0 3eo t*j> 228 c & 52c; Sep * 5 se Ja5g OS (6 J5 oo ll 2 .a *8 J4 a 8 3S . m ji a o <J JS 5 5 1.5 i :I=*2?is t i all u3*O5 "C1j3g 2S 3i ! o= ; ,t S3 3V !*s [ H8*> 108 109 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table XI. Coefficients of Transmission (E/) of Various Types of Flat Roofs Covered with Built-Up Roofing* TYPICAL CONSTRUCTION Without Chungs With Metal Lath anp Plaster Ceilings* TYPE OF ROOF DECK Thickness or Roof Deck (Inches) /HIT WJUlAXlMl tv* cohcilTTC. tr "fe/urforT/-* ii ' i j" irri CtlLtHfi' m/OtATWK/ C0HC?tT&7|*|T Precast Cement Tile Concrete Concrete Concrete 1H itf/UltCTloOiHtjf tOQfWU : uiiQLtfion ROOFFinlt^Ui / Wood Wood Wood Wood 4` liN/UL/CTtOttj mSftf/tUZKTS&*.lnn} irl/UUTian/ HQgFIHQ Gypsum Fiber Concrete* (2 in.) on Plasterboard (H in.) Gypsum Fiber Concrete* (3 in.) on Plasterboard (H in.) Gypsum Fiber Concrete* (2 in.) on Rigid Insula- latlon Board (H in.) Gypsum Fiber Concrete* (2 in.) on Rigid Insula tion Board <1 in.) . EOPPllMKt/f0j LATli/ MQFWIfCOlOUTltpflrtyj m Flat Metal Roofs . Coefficient of transmis sion of bare corrugated iron (no roofing) is 1.50 Btu per hour per square foot of projected area per degree Fahrenheit dif ference in temperature, based on an outside wind velocity of 15 mph._______ "Computed from factors marked by-in Table 2. , , .. `Nominal thicknesses specified--actual thicknesses used in calculations. "Gypsum fiber concrete--87H Per cent gypsum. 12H per cent wood fiber. 2H 3H 2M 3 110 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Coefficients ore expressed in Btu per hour per square foot per degree Fahrenheit difference in temperature between the air on the two sides, end are based on an outside wind velocity of 15 mph. WITHOUT CEILING--UNDER SIDE OF ROOF EXPOSED WITH METAL LATH AND PLASTER CEILINGS* Rigid Insulation (H In.) d d 5 ji 5 J5 M d _ag 13 1 1| Z -a S ao 3 9 a W S oa 1 JaO 3 9 a 9 I d T2 1 ho O X O d N ; 0 ' 3 9 3 o O .55 jd d _d a asaos JS 9 a *V 5 M 3oa5 J33 0o g 9 aa a -a `3 '5 jd J3 5 1; s .ja0 o' O o o ABC D E F G H I J K L MN O .9 i p 0.84 0.37 0.24 0.18 0.14 0.22 0.16 0.13 0.43 0.26 0.19 0.15 0.12 : 0.18 0.14 0.11 0.82 0.37 0,24 0.17 0.14 0.22 0.16 0.13 0.42 0.26 0.19 0.15 0.12 0.18 0.14 0.72 0.34 0.23 0.17 0.13 0.21 0.16 0.12 0.40 0.25 0.18 0.14 0.12 0.17 0.13 0.84 0.33 0.22 0.16 0.13 0.21 0.15 0.12 0.37 0.24 0.18 0.14 0.11 0.17 0.13 0.11 0.11 0.11 0.49 0.28 0.20 0.15 0.12 0.19 6.14 0.12 0.32 0.21 0.16 0.13 0.11 0.15 0.12 OtlO 0.37 0.24 0.18 0.14 0.11 0.17 0.13 0.11 0.26 0.19 0.15 0.12 0.10 0.14 0.11 0.095 0.82 0.22 0.16 0.13 0.11 0.16 0.12 0.10 0.24 0.17 0.14 0.11 0.097 0.13 0.11 0.092 0.23 0.17 0.14 0.11 0.096 0.13 0,11 0.091 0.18 0.14 0.12 0.10 0.087 0.11 0.096 0.082 0.40 0.25 0.18 0.14 0.12 0.17 0.13 0.11 0.27 0.19 0.15 0.12 0.10 0.14 0.12 0:097 0.32 0.22 0.16 0.13 0.11 a.i5 0.12 0.10 0.23 0.17 0.14 o.n 0.097 0.13 0.11 0:091 0.26 0.19 0.15 0.12 0.10 0.14 0.11 0.10 0.20 0.16 0.13 0.11 0.09 0.12 -0.10 0.087 0.19 0.15 0.12 0.10 0.09 0.12 0.10 0.08 0.16 0.13 0.11 0.09 0.08 0.10 0.09 0*077 0.95 0.39 0.25 0.18 0.14 0.23 0.17 0.13 0.46 0.27 0.19 0.15 0.12 0.18 0.14 0.11 *These coefficients may be used with sufficient accuracy for wood lath and plaster, or plasterboard and plaster ceilings. It is assumed that there is an air space between the under side of the roof deck and the upper side of the ceiling. . Ill HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES U= 1 4.0 4.0 . 0.5 1 6.0 + 9.20 + 5.0 + 3.3 + 1.65 1 0.167 + 0.435 + 0.80 + 0.152 + 0.606 . = 0.46 Btu per hour per square foot per degree Fahrenheit difference in tempera ture between the air on the two sides. . The coefficients in the tables were determined by calculations similar to those shown in Example 1, using Fundamental Formulae 3, 4 and 5 and the values of k (or C),fi, f0 and a indicated in Table 2 by asterisks. In computing heat transmission coefficients of floors laid directly on the ground (Table 10), only one surface coefficient (/i) is used. For example, the value of U (or a 1-in. yellow pine floor (actual thickness, 25/32 in.) placed directly on 6-in. concrete on the ground, is determined as follows: U ------------ ---- --------- ---- = 0.48 Btu per hour per square foot per degree difference 1 , 0.781 , 6.0 1.65 + 0.80 ^ 12.0 in temperature between the ground and the air immediately above the floor. 13.Table Coefficients of Transmission (tf) of Doors, Windows, Skylights and Glass Walls Coefficients are based on d wind velocity of 16 mPh, and are expressed in Btu per hour Per square foot per degree Fahrenheit difference in temperature between the air inside and outside of the door, window, skylight or wdl A. Windows and Skylights Description u Single.................................................................. . 1.13. ` Double.___............................................ _....... . 0.45 Triple.......................................................... 0:281" Nominal Thickness Inches i lK iK W 2 2H 3 B. Solid Wood Doorsh c Actual Thickness Inches 0 Exposed Door % 1^6 We W W 2H 2% 0.69 0.59 0.52 0.51 0.46 0.38 0.33 </* With Glass Storm Door 0.42 0.38 0.35 0.35 0.32 0.28 0.25 C. Glass Walls Description Hollow glass tile wall, 6x6 x 2 in. thick blocks, wind velocity 15 mph, outside surface: still air. inside surface StilJ air, outside and inside surface. . V 0.60 0.48 __ _______uug ttUU rvu VUI1UU....~>A, auu I'uiaiu, icviscU CU1UUI1, Computed using C * 1.15 for wood;/* = 1.65 and/0 6.0. < ^ . U is sufficiently accurate to use the same coefficient of transmission for doors containing thin wood panels as that of single panes of glass, namely, 1.13 Btu per hour per square foot per degree difference between inside and outside air temperatures. . *These values may also be used with sufficient accuracy for wood storm doors. Neglect storm doors if loose and use values for exposed doors. . 113 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 Rigid insulation refers to so-called insulation board which may be used structurally, such as for sheathing. Flexible insulation refers to the. blankets, quilts or semi-rigid types of insulation. Actual thicknesses of lumber are used in the computations rather than nominal thicknesses. The computations for wood shingle roofs applied over wood stripping are based on 1 by 4 in. wood strips, spaced 2 in. apart. Since no reliable figures are available concerning the conductivity, of Spanish and French clay roofing tile, of which there are many varieties, the figures for such types of roofs were taken the same as for slate roofs, as it is probable that the values of U for these two types of roofs will compare favorably. The thicknesses upon which the coefficients in Tables 3 to 13 inclusive, are based are as follows: . Brick veneer......................................................... ....................... -........... 4 in. Plaster and metal lath:............................................................................ % in. Plaster (on wood lath, plasterboard, rigid insulation, board form, or corkboard)________________________________ _______ .-- in. Slate (roofing)------------ --------- -----------------------------;-------------------- -- H in. Stucco on wire mesh reinforcing.................... ..................... ................. 1 in. Tar and gravel or slag-surfaced built-up roofing________________ in. 1-in. lumber (S-2-S)--------------------------------------------------------- ---------- 2%2 in. IRrin. lumber (S-2-S).................................................................. -------- 1M 6 in. 2-in. lumber (S-2-S)................ ............................................................... 1% in. 2*fin. lumber (S-2-S)........................................................ .......... .......... 2^ in. 3-in. lumber (S-2-S).......................... ................... ............................... -- 2$^ in. 4-in. lumber (S-2-S)__________ ________________ _________________ in. Finish flooring (maple or oak)........ .................. ........................ .......... li6 in. Solid brick walls are based on 4 in. hard brick (high density) and the remainder common brick (low density). Stucco is assumed to be I in. thick on masonry walls. Where metal lath and plaster are specified, the metal lath is neglected. The coefficients of transmission of the pitched roofs in Table 12 apply where the roof is over a heated attic or top floor so the heat passes directly through the roof structure including whatever finish is applied to the underside of the roof rafters. Combined Coefficients of Transmission If the attic is unheated, the roof structure and ceiling of the top floor must both be taken into consideration, and the combined coefficient of transmission determined. The formula for calculating the combined coefficient of transmission of a top floor ceiling, unheated attic space, and pitched roof, per square foot of ceiling area, is as follows: Ur X C/Ce Ur + t/c. (6) where U = combined coefficient to be used with ceiling area. XJt -- coefficient of transmission of the roof. /ce = coefficient of transmission of the ceiling. n = the ratio of the area of the roof to the area of the ceiling. 114 CHAPTER 5. HEAT TRANSMISSION COEFFICIENTS AND TABLES Stating the formula in terms of the total heat resistance of the ceiling and roof, 1p ~V ~ 1 UZr 4- ___ + Ur Xn (7) In selecting the values to be used for Vt and Ua it should be noted that the under surface of the roof and the upper surface of the ceiling are more nearly equivalent to the boundary surfaces of an internal air space than they are to the external surfaces of a wall. It would be more nearly correct to use a value of 2.2 rather than the usual value of 1.65 as coef ficients for these surfaces. In most cases this would make only a minor change in U. It should be noted that the over-all coefficient should be multiplied by the ceiling and not the roof area. If the unheated attic space between the roof and ceiling has no dormers, windows or vertical wall spaces the combined coefficients may be used for determining the heat loss through the roof construction between the attic and top floor ceiling. If the unheated attic contains windows and vertical wall spaces these must be taken into consideration in calculating the roof area and also its coefficient t/r. In this case an approximate value of Ur may be obtained as the summation of the coefficient of each individual section such as the roof, vertical walls or windows times its percentage of total area. This coefficient may be used with reasonable accuracy in the above formulae. If, however, there are roof ventilators such that the attic air is substantially at outside temperature, then the roof should be neglected and only the coefficient for the top floor ceiling construction used. . Basements and Unheated Rooms The heat loss through floors into basements and into unheated rooms kept closed may be computed by assuming a temperature for these rooms of 32 F. The coefficients of transmission for concrete floors on ground (Table 10) are based on the assumption that the heat-resisting value of the floor extends downward and stops at the under side of the concrete. It is probable, however, that the dirt underneath has some heat-resistance value extending to a considerable depth, which would result in substan tially lower heat transmission coefficients than given in Table 10. This subject is being investigated. Additional information on the inside and outside temperatures to be used in heat loss calculations is given in Chapter 7. A.S.H.V.E. Research Reports: REFERENCES No. 852--Effects of Air Velocities on Surface Coefficients, by F. B. Rowley, A. B. Algren and J. L. -Blackshaw (A.S.H.V.E. Transactions, Vol. 36, 1930, p. 123). No. 895--Wind Velocity Gradients Near a Surface and Their Effect on Film Con ductance, by F. C. Houghten and Paul McDermott (A.S.H.V.E. Trans actions, Vol. 37, 1931, p. 301). ' No. 914--Surface Coefficients as Affected by Direction of Wind, by F. B. Rowley and W. A. Eckley (A.S.H.V.E. Transactions, Vol. 38, 1932, p. 33). No. 915--Conductivity of Concrete, by F. C. Houghten and Carl Gutberlet (A.S. H.V.E. Transactions, Vol. 38, 1932, p. 47). . No. 964--The Heat Conductivity of Wood at Climatic Temperature Differences, by F. B. Rowley (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 329). 115 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 f No. 996--Insulating Value of Bright Metallic Surfaces, by F. B. Rowley (A.S.H.V.E. Transactions, Vol. 40, 1934, p. 413). , No- 1026--Thermal Properties of Concrete Construction, by F. B. Rowley, A. B. Algren and Clifford Carlson (A.S.H.V.E. Transactions, Vol. 42, 1936, ... No. 1048--pT.h3e3rm). al Proper.ties of Concrete Construction, by F. B. Rowley, A. B. . Algren and Robert Lander (A.S.H.V.E. Transactions, Vol. 43, 1937, Chapter 6 Insulating EP-ff3e3c)t. of Successive Air Spaces Bounded by Bright Metallic Surfaces, by L. W. Schad (A.S.H.V.E. Transactions, Vol. 37, 1931, p. 285). Importance of Radiation in Heat Transfer Through Air Spaces, by E. R. Queer (A.RSa.Hd.iaVt.iEon. TanrdanCsoancvteioctniosn, VAoclr.o3ss8,A1i9r3S2p,apc.es77in). Frame Construction, by G. B. Wilkes and C. M. F. Peterson (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 351). Radiation and Convection from Surfaces in Various Positions, by G. B. Wilkes and C. M. F. Peterson (A.S.H.V.E. Transactions, Vol, 44, 1938, p. 513). Properties of Metal Foil as an Insulating Material, by J. L. Gregg (Refrigerating EngTihneremrinagl ,InMsualya,ti1o9n3w2)i.th Aluminum Foil, by R. B. Mason (Industrial and Engineering CheTmheisrtmrya, lMInasrcuhla, t1io9n33o)f. Buildings, Technical Paper No. 11 (.American Architect, May, 193H4)e.at Insulation as Applied to Buildings and Structures, by E. A. Allcut, University of THooruosnetoIn, s1u9l3a4t.ion, Its Economies and Applications, by Russell E. Backstrom (Report of the National Committee on Wood Utilization, United States Government Printing OffiHcee, amt Tir)a.nsmission Through Building Materials, by F. B. Rowley and A. B. Algren, University of Minnesota Engineering Experiment Station Bulletin No. 8. Calculation of Heat Transmission, by Margaret Fishenden and Owen A. Saunders. Heating, Ventilating and Air Conditioning, by Harding and Willard, Revised Edition, 1932. Heat Transmission, by W. H. McAdams. Industrial Heat Transfer, by Shack. 116 AIR LEAKAGE ,Nature of Air Infiltration, Infiltration Through Walls, Window Leakage, Door Leakage, Selection of Wind Velocity Crack Length used for Computations, Multi-Story Buildings, Heat Equivalent of Air Infiltration AIR leakage losses are those resulting from the displacement of heated air in a building by unheated outside air, the interchange taking place through various apertures in the building, such as cracks around doors and windows, fireplaces and chimneys. This leakage of air must be considered in heating and cooling calculations. (See Chapters 7 and 8.) NATURE OF AIR INFILTRATION The natural movement of air through building construction is due to two causes. One is the pressure exerted by the wind; the other is the difference in density of outside and inside air because of differences in temperature. The wind causes a pressure to be exerted on one or two sides of a building. As a result, air comes into the building bn the windward side through cracks or porous construction, and a similar quantity of air leaves on the leeward side through like openings. In general the resis tance to air movement is similar on the windward to that on the leeward side. This causes a building up of pressure within the building and a lesser air leakage than that experienced in single wall tests as determined in the laboratory. It is assumed that actual building leakages owing to this building up of pressure will be 80 per cent of laboratory test values. While there are cases where this is not true, tests in actual buildings substantiate the factor for the general case. Mechanical ventilating systems are frequently designed to produce positive or negative pressures in an enclosure which are greater or lower than prevalent wind pressures.. In such designs, if the rate at which air is specified to be introduced to or removed from the enclosure by positive means exceeds the infiltration rate, it is common practice to use the greater value in determining the heating capacity to warm the outside air. The air exchange owing to temperature difference, inside to outside, is not appreciable in low buildings. In tall, single story buildings with openings near the ground level and near the ceiling, this loss must be considered. Also in multi-story buildings it is a large item unless' the sealing between various floors and rooms is quite perfect. This tempera ture effect is a chimney action, causing air to enter through openings at lower levels and to leave at higher levels. :' 117 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 A complete study of all of the factors involved in air movement through building constructions would be very complex. Some of the complicating factors are: the variations in wind velocity and direction; the exposure of the building with respect to air leakage openings and with respect to adjoining buildings; the variations in outside temperatures as influencing the chimney effect; the relative area and resistance of openings on the windward and leeward sides and on the lower floors and on the upper floors; the influence of a planned air supply and the related outlet vents; and the variation from the average of individual building units. A study of infiltration points to the need for care in the obtaining of good building construction, or unnecessarily large heat losses will result. INFILTRATION THROUGH WALLS Table 1 gives data on infiltration through brick and frame walls. The' brick walls listed in this table are walls which show poor workmanship and which are constructed of porous brick and lime mortar. For good workmanship, the leakage through hard brick walls with cement-lime mortar does not exceed one-third the values given. These tests indicate that plastering reduces the leakage by about 96 per cent ; a heavy coat of cold water paint, 50 per cent; and 3 coats of oil paint carefully applied, 28 per cent. The infiltration through walls ranges from 6 to 25 per cent of that through windows and doors in a 10-story office building, with imperfect sealing of plaster at the baseboards of the rooms. With perfect sealing the range is from 0.5 to 2.7 per cent or a practically negligible quantity, which indicates the importance of good workmanship in proper sealing at the baseboard. It will be noted from Table 1, that the in filtration through properly plastered walls can be neglected. The value of building paper when applied between sheathing and shingles is indicated by Fig. 1, which represents the effect on outside construction only, without lath and plaster. The effectiveness of plaster properly applied is no justification for the use of low grade building paper or of the poor construction of the wall containing it. Not only is it Table 1. Infiltration Through Walls3 Expressed in cubic feet per square foot per hour . Trra or Wall Worn Ybloott, Miles raa Hotjb . . 5 10 15 2 25 30 SX in. Brick Wall------ 1 pja^redTM. 1.75 4.20 7.85 12.2 18.6 22.9 0.017 0.037 0.066 0.107 0.161 0.236 13 in. Brick Wall-------- {&5lI 1.44 3.92 7.48 11.6 16.3 21.2 0.005 0.013 0.025 0.043 0.067 0.097 Frame Wall, with lath and plaster1' 0.03 0.07 0.13 0.18 0.23 0.26 The values given in this table are 20 per cent less than test values to allow for building up of pressure in rooms and are based on test data reported in the papers listed at the end of this chapter. . bWall construction: Bevel siding painted or cedar shingles, sheathing, building paper, wood lath and 8 coats gypsum plaster. 118 CHAPTER 6. AIR LEAKAGE Fig. 1. Infiltration Through Various Types of Shingle Construction difficult to secure and maintain the full effectiveness of the plaster but also it is highly desirable to have two points of high resistance to air flow with an air space between them. The amount of infiltration that may be expected through single walls used in farm and other shelter buildings, is shown in Fig. 2. The infil tration indicated in Figs. I and 2 is that determined in the laboratory and should be multiplied by the factor 0.80 to give proper working values. Fig. 2. Infiltration Through Single Surface Walls Used in Farm and Other Shelter Buildings 119 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Infiltration Through Windows Expressed in Cubic Feel pa Foot of Crack pa Hours Ttpb of Window R^UAHTfl Wind Velocitt, Miles pbb Houb , 5 10 15 20 25 30 Around frame in masonry wall--not calkedb 3.3 8.2 14.0 Around frame in masonry wall--calked**------ 0.5 1.5 2.6 Around frame in wood frame construction**-- 2.2 6.2 10.8 Double-Hung Total for average window, non-weather- Wood Sash Windows stripped, Hs-in. crack and J-in. clearance, 6.6 21.4 39.3 Includes wood frame leakage**--------_ (Unlocked) Ditto, weatherstripped**----------------------------- 4.3 15.5 23.6 20.2 3.8 16.6 59.3 35.5 27.2 4.8 23.0 80.0 48.6 34.6 5.8 30.3 103.7 634 Total for poorly fitted window, non-weatherstripped, 56-in. crack and %-in. clearance. Includes wood frame leakage**------------------ Ditto, weatherstripped**--------------------------- 26.9 69.0 110.5 5.9 18.9 34.1 153.9 51.4 199.2 70.5 249.4 .91.5 Double-Hung Non-weatherstripped, locked---------------- ----- Metal Non-weatherstripped, unlocked------------ Windows! Weatherstripped, unlocked------ ------------- -- 20 20 6 45 47 19 70 74 32 96 125 154 104 137 170 46 60 76 Rolled Section Steel . Sash Windows'1 Industrial pivoted, V^-in. cracks----------------- 52 108 Architectural projected, ki-m. crackb--------- 15 36 Architectural projected, %-in. crackb--------- 20 52 Rtfidential casement, &*iiL crack*-------------- 6 18 Residential casement, 16-in. crack*--.------ 14 32 Heavy casement section, projected, Ife-in. cracki------------------- ------------ 3 10 Heavy casement section, projected Ife-in. cracki.----------------------------------------------- 8 24 176 62 88 33 52 18 38 244 86 116 47 76 26 54 304 112 152 60 100 36 72 372 139 182 74 128 48 92 Hollow Metal, vertically pivoted window'.------- 30 88 145 186 221 242 The values given in tins table, with the exception of those for double-hung and hollow metal windows, are 20 per cent less than test values to allow for building up of pressure in rooms, and are based on test data reported in the papers listed at the end of this chapter. bThe values given for frame leakage are per foot of sash perimeter as determined fordouble-bung wood windows. Some of the frame leakage in masonry walls originates in the brick wall itself and cannot be prevented by calking. For the additional reason that calking is not done perfectly and deteriorates with - time, it is considered advisable to choose the masonry frame leakage values for calked frames as the average determined by the calked and not-caiked tests. cThe fit of the average double-bung wood window was determined as . crack and %-in. clearance by measurements on approximately 600 windows under heating season conditions. dThe values given are the totals for the window opening per foot of sash perimeter and include frame leakage and so-called elsewhere leakage. The frame leakage values included are for wood frame construction but apply as well to masonry construction assuming a 50 per cent efficiency of frame calking. A 5-in. crack and clearance represents a poorly fitted window, much poorer than average. (Windows tested in place in building. . elndustrial pivoted window generally used In industrial buildings. Ventilators horizontally pivoted at center or slightly above, lower part swinging out. bArchitectura! projected made of same sections as industrial pivoted except that outside framing member is heavier, and it has refinements in weathering and hardware. Used in semi-monumental buildings such as schools. Ventilators swing in or out and are balanced on side arms. &-in. crack is obtainable in the best practice of manufacture and installation, %-in. crack considered to represent average practice. 101 same design and section shapes as so-called heavy section casement but of lighter weight. j-in. crack is obtainable in the best practice of manufacture and installation, crack considered to represent average praJcMticaed. e of heavy sections. Ventilators swing in or out and stay set at any degree of opening. J6-iu. crack Is obtainable in the best practice of manufacture and installation, }*in. crack considered to represent averkaWgeItbprarecatiscoen.able care In Installation, leakage at contacts where windows are attached to steel frame work and at.mullions is negligible. With %-in. crack, representing poor installation, leakage at contact with steel framework is about one-third, and at mullions about one-sixth of that given for industrial pivoted windows in the table. 120 CHAPTER 6: AIR LEAKAGE WINDOW LEAKAGE The amount of infiltration for various types, of windows is given in Table 2. The fit of double-hung wood windows is determined by crack and clearance. Crack thickness is equivalent to one-half .the difference between the inside window frame dimension and the outside sash width. The difference between the width of the window frame guide and the sash thickness is considered as the clearance. The length of the perimeter opening or crack for a double-hung window is equal to three times the width plus two times the height, or in other words, it is the outer sash perimeter length plus the meeting rail length. Values of leakage shown in Table'2 for the average double-hung wood window'were determined by setting the average measured crack and clearance found in a field survey of a large number of windows on nine windows tested in the laboratory. In addition, the table gives figures for a poorly fitted window. All of the figures for double-hung wood windows' are for the unlocked condition. Just how a window is closed, or fits when it is closed, has considerable influence on the leakage. The leakage will be high if the sash are short, if the meeting rail members are warped, or if the frame and sash are not fitted squarely to each other. It is possible to have a window with approximately the average crack and clearance that will have a leakage at least double that of the figures shown. Values for the average doublehung wood window in Table 2 are considered to be easily obtainable figures provided the workmanship on the window is good. Should it be known that the windows under consideration are poorly fitted, the larger leakage values should be used. Locking a window generally decreases its leakage, but in some cases may push the meeting rail members apart and increase the leakage. On windows with large clearances, locking will usually reduce the leakage. Wood casement windows may be assumed to have the same unit leakage as for the average double-hung wood window when properly fitted. Locking, a normal operation.in the closing of this type of window, maintains the crack at a low value. For metal pivoted sash, the length of crack is the total perimeter of the movable or ventilating sections. Frame leakage on steel windows may be neglected when they are properly grouted with cement mortar into brick work or concrete. When they are not properly sealed, the linear feet of sash section in contact with steel work at mullions should be figured at 25 per cent of the values for industrial pivoted windows as given in Table 2. When storm sash are applied to well fitted windows, very little re duction in infiltration is secured, but the application of the sash does give an air space which reduces the heat transmission and helps prevent the frosting of the windows. When storm sash are applied to poorly fitted windows, a reduction in leakage of 50 per cent may be secured. DOOR LEAKAGE Doors vary greatly in fit because of their large size and tendency to warp. For a well fitted door, the leakage values for a poorly fitted doublehung wood window may be used. If poorly fitted, twice this figure should 121 be used. If weatherstripped, the values may be reduced one-half. A single door which is frequently opened, such as might be found in a store, should have a value applied which is three times that for a well fitted door. This extra allowance is for opening and closing losses and is kept from being greater by the fact that doors are not used as much in the coldest and windiest weather. The infiltration rate through swinging and revolving doors is generally a matter of judgment by the engineer making cooling load determinations and in the absence of adequate research data the values given in Table 3 represent current engineering practice. These values are based on the average number of persons in a room at a specified time, which may also be the same occupancy assumed for determining the outside ventilation requirements outlined in Chapters 3 and 8. .- Table 3. Infiltration Through Outside Doors for Cooling Loads3 Expressed in Cubic Feet per Minute per Person in Room Application Path 36 IN. SWINGING Doobs, Single Entrance^ .. 7.5 4.5 7.0 6.0 25.0 8.0 2:5 7.0 2.5 3.5 5.0 3.5 3.0 2.0 2.5 2.5 3.5 . For doors located in only one wall or where doors in other walla are of revolving type. . . : bVestibules with double pair swinging doors, infiltration may be assumed 75 per cent of swinging door values. Infiltration for 72 in. revolving doors may be assumed 60 per cent of swinging door values. SELECTION OF WIND VELOCITY Although all authorities do not agree upon the value of the wind veloc ity that should be chosen for any given locality, it is common engineering practice to use the average wind velocity during the three coldest months of the year. Average wind velocities for the months of December, January and February for various cities in the United States and Canada are given in Table 2, Chapter 7. . In considering both the transmission and infiltration losses, the more exact procedure would be to select the outside temperature and the wind velocity corresponding thereto, based on Weather Bureau records,, which would result in'the maximum heat demand. Since the proportion of transmission and infiltration losses varies with-the construction and is 122 ` CHAPTER 6. AIR LEAKACE different for every building, the proper combination of temperature and wind velocity to be selected would be different for every type of building, even in the same locality. Furthermore, such a procedure would necessi tate a laborious cut-and-try process in every case in order to determine the worst combination of conditions for the building under'consideration. It would also be.necessary to consider heat lag due to heat capacity in the case of heavy masonry walls, and other factors, to arrive at the most accurate solution of the problem. Although heat capacity should be con sidered wherever possible, it is seldom possible to accurately determine the worst combination of outside temperature and wind velocity for a given building and locality. The usual procedure, with modification explained in Chapter 7, is to select an outside temperature which is not more than 15 F above the lowest recorded, and the average wind velocity during the months of December, January and February. The direction of prevailing winds may usually.be included within an angle of about 90 deg. The windows that are to be figured for prevailing and non-prevailing winds will ordinarily each occupy about one-half the perimeter of the structure, the proportion varying to a considerable extent with the plan of the structure. (See discussion of wind movement in Chapter 37 and Table 2 in Chapter 7.) CRACK LENGTH USED FOR COMPUTATIONS In no case should the amount of crack used for computation be less than half of the total crack in the outside walls of the room. Thus, in a room with one exposed wall, take all the crack; with two exposed walls, take the wall having the most crack; and with three or four exposed walls, take the wall having the most crack; but in no case take less than half the total crack. For a building having no partitions, whatever wind enters through the cracks on the windward side must leave through the cracks on the leeward side. Therefore, take one-half the total crack for com puting each side and end of the building. The amount of air leakage is sometimes roughly estimated by assuming a certain number of air changes per hour for each room, the number of changes assumed being dependent upon the type, use and location of the room, as indicated in Table 4. This method may be used to. advantage as a check on the calculations made in the more exact manner. MULTI STORY BUILDINGS In tall buildings, infiltration may be considerably influenced by tem perature difference or chimney effect which will operate to produce a head that will add to the effect of the wind at lower levels and subtract from it at higher levels. On the other hand, the wind velocity at lower levels may be somewhat abated by surrounding obstructions. Further more, the chimney effect is reduced in multi-story buildings by the partial isolation of floors preventing free upward movement, so that wind and temperature difference may seldom cooperate to the fullest extent. Making the rough assumption that the neutral zone is located at mid height of a building, and that the temperature difference is 70 F, the following formulae may be used to determine an equivalent wind velocity 123 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Table 4. Air Changes Taking Place under Average Conditions Exclusive of Air Provided for Ventilation Kind or Room ob Building Ncubes or Aib Changes Taking Placs per Boub i lK 2 2 Hto % 2 to 3 2 1 to 2 1 to 2 2 2 to 3 1 J-3 to 3 , to be used in connection with Tables 1 and 2 that will allow for both wind velocity and temperature difference: Me = VJlf - 1.7S a (1) where Me = VAf* + 1.75 b (2) Mv = equivalent wind velocity to be used in conjunction with Tables 1 and 2. M = wind velocity upon which infiltration would be determined if tem perature difference were disregarded. a = distance of windows under consideration from mid-height of building if above mid-height. b = distance if below mid-height. The coefficient 1.75 allows for about one-half the temperature difference head. For buildings of unusual height, Equation 1 would indicate negative infiltration at the highest stories, which condition may, at times, actually exist. Sealing of Vertical Openings In tall, multi-story buildings, every effort should be made to seal off vertical openings such as stair-wells and elevator shafts from the re mainder of the building. Stair-wells should be equipped with self-closing doors, and in exceptionally high buildings, should be closed off into sections of not over 10 floors each. Plaster cracks should be filled. Elevator enclosures should be tight and solid doors should be used. If the sealing of the vertical openings is made effective, no allowance need be made for the chimney effect. Instead, the greater wind move ment at the greater heights makes it advisable to install additional heating surface on the upper floors above the level of neighboring buildings, this additional surface being increased as the height is increased. One arbitrary rule is to increase the heating surface on .floors above neighboring buildings by an amount ranging from 5 per cent to 20 per cent. This extra heating surface is required only on the windward side and on windy days, and hence automatic temperature control is especially desirable with such installations. . 124 CHAPTER 6. AIR LEAKAGE In stair-wells that are open through many floor levels although closed off from the remainder of each floor by doors and partitions, the strati fication of air makes it advisable to increase the amount of heating surface at the lower levels and to decrease the amount at higher levels even to the point of omitting all heating surface on the top several floor levels. One rule is to calculate the heating surface of the entire stair-well in the usual way and to place 50 per cent of this in the bottom third, the normal amount in the middle third and the balance in the top third. HEAT EQUIVALENT OF AIR INFILTRATION Sensible Heat Loss The heat required to warm cold outside air, which enters a room by infiltration, to the temperature of the room is given by the equation: Hs = 0.24 Qd(ti - Q (3) where Hs = heat required to raise temperature of air leaking into building from to to ti Btu per hour. ' 0.24 -- specific heat of air. Q = volume of outside air entering building, cubic feet per hour. d density of air at temperature to, pounds per cubic foot. /i = room air temperature, degrees Fahrenheit. t0 -- outside air temperature, degrees Fahrenheit. Latent Heat Loss When it is intended to add moisture to air leaking into a room for the maintenance of proper winter comfort conditions, it is necessary to determine the heat equivalent to evaporate the required amount of water vapor, which may be calculated by the equation: B`-od(Jir)L < where Hi = heat required to increase moisture content of air leaking into building from Mo to Afj, Btu per hour. Q = volume of outside air entering building, cubic feet per hour. d = density of air at temperature ti, pounds per cubic foot. Mi = vapor density of inside air, grains per pound of dry air. M0 = vapor density of outside air, grains per pound of dry air. ' L = latent heat of vapor at Mi, Btu per pound. It is sufficiently accurate to use d = 0.075 lb, in which case Equation 3 reduces to 5 and if the latent heat of vapor is assumed for general condi tions as 1060 Btu per pound Equation 4 reduces to 6. Hs -- 0.018 Q (ti -- to) Hi = 0.0114 Q (Mi - Mo) (5) (6) Changing the temperature and vapor subscripts in Equations 5 and 6 to (to -- ti) and (M0 -- Mi) permits the use of these same formulas for determining the sensible and latent heat gains due to infiltration in cooling load computations. If a building has more than one room which is divided by interior walls or partitions, it is sufficiently accurate to use half of the total infiltration losses for determining the total heat requirements. Where buildings. 125 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 have no interior walls, the infiltration losses are calculated by using one-half of. the total crack, in which case the entire infiltration loss should- be considered: . -. REFERENCES A.S.H.V.E.. Research Reports: No: No. 686--Air Leakage, by F. C. Houghten and C. C. Schrader (A.S.H.V.E. Trans actions, Vol. 30, 1924, p. 105). ' 704--Air Leakage Around Window Openings, by C. C. Schrader (A.S.H.y.E. Transactions, Vol. 30; 1924, p. 313). No. 786--Infiltration Through Plastered and Unplastered Brick Walls, by F. C. Houghten and Margaret Ingels (A.S.H.V.E. Transactions, Vol. 33, 1927, . P- 377). . . . .- No. 803--Air Leakage on Metal Windows in a Modern Office Building, by F. C. Houghten and M. E. O'Connell (A.S.H.V.E. Transactions, Vol. 34,1928, p. 321). No. 815--Air Leakage Through a Pivoted Metal Window, by F. C. Houghten and M. E. O'Connell (A.S:H.V.E. Transactions, Vol. 34, 1928, p. 519). No. 826--Air Infiltration Through Various Types of Brick Wall Construction, by G. L. Larson, D. W. Nelson and C. Braatz (A.S.H.V.E. Transactions, Vol. 35, 1929, p..183). , No. 851--Air Infiltration Through Various Types of Wood Frame Construction, by G. L. Larson, D. W. Nelson and C. Braatz (A.S.H.V.E. Transactions, Vol. 36, 1930, p. 99).. . No. 909--Air Infiltration Through Double-Hung Wood Windows, by G. L. Larson, D. W. Nelson and R. W. Kubasta (A.S.H.V.E. Transactions, Vol. 37, 1931, p. 571). . No. 936--I investigation of Air Outlets in Class Room Ventilation, by G, L. Larson, D. W. Nelson and R. W. Kubasta (A.S.H.V.E. Transactions, Vol. 38, . 1932, p. 463). No. 994--Wind Velocities Near a Building and Their Effect on Heat Loss, by F. C. Houghten, J. L. Blackshaw and Carl Gutberlet (A.S.H.V.E. Trans actions, Vol. 40, 1934, p. 387). No. 1069--Heating Requirements of an Office Building as Influenced by the Stack Effect, by F. C. Houghten and Carl Gutberlet (A.S.H.V.E. Trans: actions, Vol. 43, 1937, p. 437). ; Neutral Zone in Ventilating, by J. E. Emswiler (A.S.H.V.E. Transactions, Vol. 32, 1926, p. 59). Effect of Frame Calking and Storm Sash on Infiltration Around and Through Windows, by W. M. Richtmann and C. Braatz (A.S.H.V.E. Transactions, Vol. 34, 1928, p. 547). - The Weathertightness of Rolled Section Steel Windows, by J. E. Emswiler and W. C. Randall (A.S.H.V.E. Transactions, Vol, 34, 1928, p. 527). Pressure Differences Across Windows in Relation to Wind Velocity, by J. E. Emswiler and W. C. Randall (A.S.H.V.E. Transactions, Vol. 36, 1930, p. 83). . Flue Action in Tall Buildings, by H, L. Alt (Heating, Piping and Air Conditioning, May, 1932). : Air Infiltration Through Steel Framed Windows, by D. O. Rusk, V. H. Cherry and L. Boelter (Heating, Piping and Air Conditioning, October, 1932). Influence of Stack Effect on the Heat Loss in Tall Buildings, by Axel Marin (A.S.H. V.E. Transactions, Vol. 40, 1934, p. 377). : Fuel Saving Resulting from the Use of Storm Windows and Doors, by A. P. Kratz and S. Konzo (A.S.H.V.E. Transactions, Vol. 42,1936, p. 87). The Infiltration Problem of Multiple Entrances, by A. M. Simpson and K. B. Atkinson (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, June, 1936). infiltration Characteristics of Entrance Doors, by A. M. Simpson (Refrigerating Engineering, June, 1936). 126 Chapter 7 HEATING LOAD ,Heat Demand Design Factors, Method of Procedure Inside ,and Outside Temperatures, Wind Velocity Effects Auxiliary Heat Sources, Wall Condensation, Heat loss Computation TO design any system of heating, the maximum probable heat demand must be accurately estimated in order that the apparatus installed shall be capable of maintaining the desired temperature at all times. The factors which govern this maximum heat demand--most of which are seldom, if ever, in equilibrium--include the following: 1. Outside temperature. 2. Rain or snow. 3. Sunshine or cloudiness. 4. Wind velocity. 5. Heat transmission of exposed parts of building. 6. Infiltration of air through cracks, crevices and open doors and windows. . 7. Heat capacity of materials. 8. Rate of absorption of solar radiation by exposed materials. Outside Conditions (The Weather) . J Building ' Construction 9. Inside temperatures. 10. Stratification of air. 11. Type of heating system. 12. Ventilation requirements. 13. Period and nature of occupancy. 14. Temperature regulation. . Inside Conditions The inside conditions vary from time to time, the physical properties of the building construction may change with age, and the outside conditions are changing constantly. Just what the worst combination of all of these variable factors is likely to be in any particular case is therefore con jectural. Because of the nature of the problem, extreme precision in estimating heat losses at any time, while desirable, is hard of attainment. The procedure to be followed in determining the heat loss from any building can be divided into seven consecutive steps, as follows: 1. Determine on the inside air temperature, at the breathing line or the 30-in. line, which is to be maintained in the building during the coldest weather. (See .Table 1.) 2. Determine on an outside air temperature for design purposes, based on the minimum temperatures recorded in the locality in question, which will provide for all but the most severe weather conditions. Such conditions as may exist for only a lew consecu tive hours are readily taken care of by the heat capacity of the building itself. (See Table 2.) 3. Select or compute the heat transmission coefficients for outside walls and glass; also for inside walls, floors, or top-floor ceilings, if these are next to unheated space; include roof if next to heated space. (See Chapter 5.) \' 127 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 4. Measure up net outside wall, glass and roof next to heated spaces, as well as any cold walls, floors or ceilings next to unheated space. Such measurements are made from building plans, or from the actual building. 5. Compute the heat transmission losses for each kind of wall, glass, floor, ceiling and roof in the building by multiplying the heat transmission coefficient in each case by the area of the surface in square feet and the temperature difference between the inside and outside air. (See Items 1 and 2.) 6. Select unit values and compute the heat equivalent of the infiltration of cpld air taking place around outside doors and windows. These unit values depend on the kind or width of crack and wind velocity, and when multiplied by the length of crack and the temperature difference between the inside and outside air, the result expresses the heat required to warm up the cold air leaking into the building per hour. (See Chapter 6.) . 7. The sum of the heat losses by transmission (Item 5) through the outside wall and glass, as well as through any cold floors, ceilings or roof, plus the heat equivalent (Item 6) of the cold air entering by infiltration represents the total heat loss equivalent for any building. Item 7 represents the heat losses after the building is heated and under stable operating conditions in coldest weather. Additional heat is required for raising the temperature of the air, the building materials and the mate'rial contents of the building to the specified standard inside temperature. The rate at which this additional heat is required depends upon the heat capacity of the structure and its material contents and upon the time in which these are to be heated. This additional heat may be figured and allowed for as conditions re quire, but inasmuch as the heating system proportioned for taking care of die heat losses will usually have a capacity about 100 per cent greater than that required for average winter weather, and inasmuch as most buildings may either-be continuously heated or have more time allowed Table 1. Winter Inside Dry-Bulb Temperatures Usually Specified3 Tin or .Building Deo Fabb Tire or Building Deo Fabb Schools Gymnasiums___________________ Toilets and baths ...................... Wardrobe and locker rooms----- . Playrooms... .. . -------- Hospitals-- Kitchens and laundries------------- Toilets. __ ____________ 70-72 fi8-72 55-65 70 65-68 66 60-65 75 70-72 70-80 70-95 68 66 68 70-80 Theaters-- Toilets......... .............--------------------- Hotels-- Bedrooms and baths________ Kitchens and laundries--------------Ballrooms....................... ........ .......... Toilets and service rooms.----------- Homes. ....... ........................................... Public buildings................... -.............. Warm air baths......... ..................... -- Steam baths...................... ...................... Factories and machine shops........... Foundries and boiler shops------- --- Paint shops ------------- -------------- 68-72 68-72 68 70 70 66 65-68 68 70-72 65-68 68-72 120 110 60-65 50--OU 80 The most comfortable dry-bulb temperature to be maintained depends on the relative humidity and air motion. These three factors considered together constitute what is termed the effective temperature. (See Chapter 3.) . CHAPTER 7. HEATINC LOAD for heating-up during the few minimum temperature days, no allowance is made except in the size of boilers or furnaces. INSIDE TEMPERATURES The inside air temperature which must be maintained within a building and which should always be stated in the heating specifications is under stood to be the dry-bulb temperature at the breathing line, 5 ft above the floor, or the 30-in. line, and not less than 3 ft from the outside walls. Inside air temperatures, usually specified, vary in accordance with the use to which the building is to be put and Table 1 presents values which con form with good practice. The proper dry-bulb temperature to be maintained depends upon the relative humidity and air motion, as explained in Chapter 3. In other words, a person may feel warm or cool at the same dry-bulb temperature, depending on the relative humidity and air motion. The optimum winter effective temperature for sedentary persons, as determined at the A.S.H. V.E. Research Laboratory, is 66 deg. According to Fig. 6, Chapter 3, for so-called still air conditions, a relative humidity of approximately 50 per cent is required to produce an effective temperature of 66 deg when the dry-bulb temperature is 70 F.; However, even where provision is made for artificial humidification, the relative humidity is seldom maintained higher than 40 per cent during the extremely cold weather, and where no provision is made for humidifica tion, the relative humidity may be 20 per cent or less. Consequently, in using the figures listed in Table 1, consideration should be given to whether provision is to be made for humidification, and if so, the actual relative humidity to be maintained. Temperature at Proper Level: In making the actual heat loss compu tations, however, for the various rooms in a building.it is often necessary to modify the temperatures given in Table 1 so that the air temperature at the proper level will be used. By air temperature at the proper level is meant, in the case of walls, the air temperature at the mean height be tween floor and ceiling; in the case of glass, the air temperature at the mean height of the glass; in the case of roof or ceiling, the air temperature at the mean height of the roof or ceiling above the floor of .the heated room; and in the case of floors, the air temperature at the floor level. In the case of heated spaces adjacent to unheated spaces, it will usually be sufficient to assume the temperature in such spaces as the mean between the temperature of the inside heated spaces and the outside air tempera-, ture, excepting where attic temperature may be calculated as discussed later or where the combined heat transmission coefficient of the roof and ceiling can be used, in which case the usual inside and outside tempera tures should be applied. (See discussion regarding the use of combined coefficients of roofs, attics and top-floor ceilings Chapter 5. Attic Temperature: It is the practice in many cases to estimate the heat loss through top-floor ceilings by assuming the attic temperature to be the mean between the inside and outside temperatures. In the case of attics with thick insulations between the ceiling joists, the attic tem perature will ordinarily be only a few degrees above the outside tempera tures rather than the mean between the inside and outside temperatures:-: 129 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Therefore, calculations based on the latter assumption are likely to be somewhat in error. A formula for calculating attic temperatures is: ' , _ AcUch -F to (AtUt -F A-wUvr ~1~ AgUg) ArUr + Ay,Uv, + AlUt + AcUc wher(ea = attic temperature, degrees Fahrenheit. t\ -- inside temperature near top Boor ceiling, degrees Fahrenheit. to -- outside temperature, degrees Fahrenheit. Ac = area of ceiling, square feet. ,,, ' ' At = area of roof, square feet. Av = area of net vertical wall surface, square feet. A g = area of glass, square feet. Uc -- coefficient of transmission of ceiling, based on surface coefficient of 2.20 (upper surface, see Chapter 5). Ut ~ coefficient of transmission of roof, based on surface coefficient of 2.20 (lower surface, see Chapter 5). Uw ~ coefficient of transmission of vertical wall surface. Ug = coefficient of transmission of glass. Example 1. Calculate the temperature in an unheated attic, assuming the following conditions: ti = 70; to ~ 10; Ac -- 1000; At = 1200; Aw -- 100; Ag = 10; I7r = 0.50; Uc = 0.40; U,, = 0.30; Ug = 1.13. Solution: Substituting these values in Equation 1: : (1000 X 0.40 X 70) + 10 [(1200 X 0.50) + (100 X 0.30) + (10 X 1.13)1 (1200 X 0.50) + (100 X 0.30) -F (10 X 1.13) + (1000 X 0.40) 28,641 1041 27.4 F. High Ceilings: Research data concerning stratification of air in build ings are lacking, but in general it may be said that where the increase in temperature is due to the natural tendency of the warmer or less dense air to rise, as where a direct radiation system is installed, the temperature of the air at the ceiling increases with the ceiling height. The relation, however, is not a straight line function, as'the amount of increase per foot of height apparently decreases as the height of the ceiling increases, ac cording to present available information1. Where ceiling heights are under 20 ft, it is'common engineering practice to consider that the Fahrenheit temperature increases 2 per cent for each, foot Of height above the breathing line.. This rule, sufficiently accurate for most cases, will give the probable air. temperature at any given level for a room heated by direct radiation. Thus, the probable temperature in a room at a point 3 ft above the breathing line, if the breathing line temperature is 70 F, will be [1.00 + (3 X .02)] 70 = 74.2 F. With certain types of heating and ventilating systems, which tend to oppose the natural tendency of warm air to rise, die temperature differ ential between floor and ceiling can be gready reduced. These include unit heaters, fan-furnace heaters, and the various types of mechanical ventilating systems. The amount of reduction is problematical in certain 'A.S.H.V.E. Research Report No. 95$--Temperature Gradient Observations in a Large Heated Space, by G. L. Larson, D. W. Nelson and O. C. Cromer (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 243).. A.S.H.V.E, Research Report No, 1011--Tests of Three Heating Systems in an Industrial Type of Build ing, by G, L. Larson, D. W. Nelson and John James (A.S.H.V.E. Transactions, Vol. 41, 1935. p. 165). 130 CHAPTER 7. HEATING LOAD instances, as it depends upon many factors such as location of heaters, air temperature, and direction and velocity of air discharge. In some cases it has been possible to reduce the temperature between the floor and ceiling by a few degrees, whereas, in other cases, the temperature at the ceiling has actually been increased because of improper design, instal lation or operation of equipment. So much depends upon the factors enumerated that it is not advisable to allow less than 1 per cent per foot (and usually more) above the breathing line in arriving at the air tem perature at any given level for anyof these types of heating and ventilating systems, unless the manufacturers are willing to guarantee that the par ticular type of equipment under consideration will maintain a smaller temperature differential for the specific conditions involved. Temperature at Floor Level: In determining mean air temperatures just above floors which are next to ground or unheated spaces, a tempera ture 5 deg lower than the breathing line temperature may be used, pro vided the breathing line temperature is not less than 55 F. OUTSIDE TEMPERATURES The outside temperature used in computing the heat loss from a build ing is seldom taken as the lowest temperature ever recorded in a given locality. Such temperatures are usually of short duration and are rarely repeated in successive years. It is therefore evident that a temperature somewhat higher than the lowest on record may be properly assumed in making the heat loss computations. The outside temperature to be assumed in the design of any heating system is ordinarily not more than 15 deg above the lowest recorded tem perature as reported by the Weather Bureau during the preceding 10 years for the locality in which the heating system is to be installed. In the case of massive and well insulated buildings in localities where the minimum does not prevail for more than a few hours, or where the lowest recorded temperature is extremely unusual, more than 15 deg above the minimum may be allowed, due primarily to the fly-wheel effect of the heat capacity of the structure. The outside temperature assumed and used in the design should always be stated in the heating specifications. Table 2 lists the coldest dry-bulb temperatures ever recorded by the Weather Bureau at the places listed. . If Weather Bureau reports are not available for the locality in question, then the reports for the station nearest to this locality are to be used, unless some other temperature is specifically stated in the specifications. In computing the average heat transmission losses for the heating season in the United States the average outside temperature from October 1 to May 1 should be used. : WIND VELOCITY EFFECTS The effect of wind on the heating requirements of any building should be given consideration under two heads: 1. Wind movement increases the heat transmission of walls, glass, and roof, affecting poor walls to a much greater extent than good walls. 2. Wind movement materially increases the infiltration (inleakage) of cold air through the cracks around doors and windows, and even through the building materials them selves, if such materials are at all porous. 131 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 Table 2. Climatic Conditions Compiled from Weather Bureau Records3 Col. A Col. B CouC Average State City Temp., Oct let-- May 1st Ala 53.8 Mobile_____ ___ ......... 1... 58.9 35.8 Phoenix.- .. ................ .... 59.5 Ark . 50.4 Little Rock....................... 51.6 Calif............. Los Angeles.........-............. 58.5 iian Francisco.................. 54.2 Colo--........ .. Denver.............................. Grand Junction............. 38.9 38.9 38.4 D. C............. Fla Ga 43.4 62.0 51.5 Savannah... ................ ...... 68.5 Idaho............ Lewiston........................... 42.3 Pocatello..................... ...... 35.7 111 36.4 Springfield........................ . 39.8 Ind..___ ___ Evansville____ ________ Indianapolis__ ___ _ 45.1 40.3 33.9 Sioux City........................ 32.6 39.8 Dodge City-.......... _........ 41.4 Ky 45.3 La................. 61.6 Shreveport........................ 56.2 Me____.:....... Eastport............................ 31.5 Portland.__ -................ 33.8 Md. ........... 43.8 Mass_______ Boston.............................. 38.1 29.6 Detroit.......................... 35.8 Marquette........................ 28.3 24.3 Minneapolis..................... 29.4 . 56.8 Mo.... ........... St. Joseph. ..................... St. Louis..... ..................... 40.7 43.6 Springfield......................... 44.3 34.0 Havre................................ 27.6 North Platte................. 37.0 35.4 39.4 Winnemucca....... ......... 37.9 N H. 33.3 N. J.._....... . Atlantic City................. 41.6 N. Y........... 35.2 Buffalo. - --. 34.8 New York............ ........ 40.7 Col. D . Lowest Tempera ture Ever Reported -10 -l -25 12 -15 -12 28 27 -29 -21 -15 -- 15 10 -8 8 -23 -28 -23 -24 -16 -25 -32 -35 --25 -26 -20 7 -5 -23 -21 -7 -18" -28 -24 -27 -41 -33 -1 -24 -22 -29 -49 -57 -29 -35 -10 -28 -35 -9 -24 -20 -14 Col. E Average Wind Vel ocity Dec:, Jan., Feb., Miles per Hour . 8.5 10.4 7.8 6.4 8.1 8.7 6.3 7.6 7.5 5.3 9.7 7.1 9.2 12.1 9.5 - 5.3 9.6 12.5 10.1 9.8 11.5 7.1 11.6 8.1 9.8 9.9 8.8 8.9 12.0 9.2 7.8 11.2 12.4 12.7 11.1 12.6 11.3 8.3 9.3 11.6 10.8 9.5 10.5 8.5 10.0 8.7 6.6 15.9 8.1 17.2 17.1 Col. F Direction of Pravait ing Wind, Dee., Jan., . Feb. N N, SW E E NW NE N. S NW N NW NE NW NW E SE W NW S SW NW NW S NW SW N SE W NW NW W W SW NW SW NW SE NW S. SE W SW S W SE NE NW NW S w NW United States data from U. S. Weather Bureau. Canadian data from Meteorological Service of Canada. 132 CHAPTER 7. heating load Table 2. Climatic Conditions Compiled from Weather Bureau Records3___ (Concluded) .. Col. A Col. B State or Province City N. M-- N. C-- N. Dak.. Ohio.-- Okla-----Oreg------ Pa --R. I------- S. C----S. Dak-- Tenn-----Texas...... Utah--..... Vt......... Va............ Wash-----W. Va...... Wis........... Wyo_____ Alta........... B. C____ Man_____ N. B........ N. S_____ Ont........... P. E. I___ Que._........ Sask______ Yukon....... _ Santa Fe.-------------... Raleigh------------- Wilmington........ ... Bismarck............. Devils Lake........ ... Cleveland---------- Columbus.... ....... ... Oklahoma City... ... Baker..............-- Portland..--_____ ... Philadelphia----. Pittsburgh........... .. Providence.-------.. Charleston--------- Columbia____ ___ _ Huron Rapid City-------.. Knoxville Memphis.... .......... ... El Paso Fort Worth______ San Antonio..___ . Modena................. Salt Lake City___ . Burlington......:..... . Lynchburg. Norfolk______ ____ Richmond____ __ . Seattle........ ............ Spokane................. . Elkins................... . Parkersburg_____1. Green Bay_______ La Crosse............... Milwaukee___ ____ Lander.................... Sheridan_________ Edmonton........;.... Vancouver............. . Victoria Winnipeg................ Fredericton............. Yarmouth________ London Ottawa.......... .......... Port Arthur______ Toronto................... Charlottetown--..... Montreal................. Quebec................... Prince Albert..... ..... Dawson___________ Cot.C Average Temp., Oct. 1stMay 1st 38.3 50.0 54.2 24.6 20.3 37.2 39.9 47.9 35.2 46.1 42.7 41.0 37.2 57.4 54.0 28.2 33.4 47.9 51.1 53.5 55.2 60.6 36.3 40.0 31.5 46.8 49.3 47.0 44.8 37.7 39.4 42.6 30.0 31.7 33.4 30.0 30.7 23.0 42.0 43.9 17.5 27.0 35.0 32.6 26.5 22.4 32.9 29.0 27.8 24.2 15.8 2.1 Col. D Lowest Tempera ture Ever Reported -13 -2 5 -45 -44 -17 -20 -17 -24 -2 -6 -20 -17 7 -2 -43 -34 -16 -9 -5 -8 4 -24 -20 -29 -7 2 -3 3 -30 -28 -27 -36 -43 -25 -40 -41 -57 2 - 1.5 -47 -35 -12 -27 -34 -37 -26.5 -27 -29 . -34 . -70 -68 Col. E Col. F Average Wind VeJodty Dec., ; Jan., Feb., Miles per Hour Direction of Prevail ing Wind, Dec., Jan., Feb. - 7.8 8.2 8.5 9.1 10.6 13.0 12.0 12.0 6.9 7.5 11.0 11.7 12.8 10.6 8.1 10.6 8.2 7.8 9.7 10.4 10.4 8.0 8.8 6.7 11.8 7.1 12.5 7.9 11.3 7.1 6.6 7.5 10.4 7.3 11.5 5.0 6.0 6.5 4.5 12.5 10.0 9.6 14.2 10.3 8.4 7.8 13.0 9.4 14.3 13.6 5.1 3.7 NE SW SW NW W SW SW 'N SE S NW W NW SW NE NW W SW S NW NW NE W SE S NW N SW SE SW W SW SW S ,,w SW . NW SW E N NW NW NW SW NW NW SW SW SW SW w S . 133 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Theoretically as a basis for design, the most unfavorable combination of temperature and wind velocity should be chosen. It is entirely possible that a building might require more heat on a windy day with a moderately low outside temperature than on a quiet day with a much lower outside temperature. However, the combination of wind and temperature which is-the worst would differ with different buildings, because wind velocity has a greater effect on buildings which have relatively high infiltration losses. It would be possible to work out the heating load for a building for several different combinations of temperature and wind velocity which records show to have occurred and to select the worst combination; but designers generally do not feel that such a degree of refinement is justified. Therefore, pending further studies of actual buildings, it is recommended that the average wind movement in any locality during December, January and February be provided for in computing (1) the heat trans mission of a building, and (2) the heat required to take care of the infiltra tion of outside air. The first condition is readily taken care of, as explained in Chapter 5, by using a surface coefficientfQ for the outside wall surface which is based on the proper wind , velocity. In case specific data are lacking for any given locality, it is sufficiently accurate to use an average wind velocity of approximately 15 mph which is the velocity upon which the heat trans mission coefficient tables in Chapter 5 are. based. In a similar manner, the heat allowance for infiltration through cracks and walls (Tables 1 and 2, Chapter 6) must be based on the proper wind velocity for a given locality. In the case of tall buildings special attention must be given to infiltration factors. (See Chapter 6.) In the past many designers have used empirical exposure factors which were arbitrarily chosen to increase the calculated heat loss on the side or sides of the building exposed to the prevailing winds. It is also possible to differentiate among the various exposures more accurately by calcu lating the infiltration and transmission losses separately for the different sides of the building, using different assumed wind velocities. Recent investigations show, however, that the wind direction indicated by Weather Bureau instruments does not always correspond; with the direction of actual impact on the building walls, due to deflection by surrounding buildings. The exposure factor, which is still in use by many engineers, is usually taken as 15 per cent, and is added to the calculated heat loss on the side or sides exposed to what is considered the prevailing winter wind. There is a need for'actual test data on this point, and pending the time when it can be secured, the question must be left to the judgment of the designing engineer. It should be remembered that the values of U in the tables in Chapter 5 are based on a wind velocity of 15 mph and that the infiltration figures are supposed to be selected from the tables in Chapter 6 to cor respond to the wind velocities given in Table 2 of the present chapter. The Heating, Piping and Air Conditioning Contractors National Associ ation has devised a method2 for calculating the square feet of equivalent direct radiation required in a building. This method makes use of ex-* *See Standards of Heating. Piping and Air Conditioning Contractors National Association. 134 CHAPTER 7. HEATINC LOAD posure factors which vary according to the geographical location and the angular situation of the construction in question in reference to pre vailing winds and the velocity of them. - AUXILIARY HEAT SOURCES The heat supplied by persons, lights, motors and machinery should always be ascertained in the case of theaters, assembly halls,, and in dustrial plants, but allowances for such heat sources, must be made only after careful consideration of all local conditions. In many cases, these heat sources should not be allowed to affect the size of the installation at all, although they may have a marked effect on the operation and con trol of the system. In general, it is safe to say that where audiences are involved, the heating installation must have sufficient capacity to bring. the building up to the stipulated inside temperature before the audience arrives. In industrial plants, quite a different condition exists, and heat sources, if they are always available during the period of human occu pancy, may be substituted for a portion of the heating installation. In no case should the actual heating installation (exclusive of heat sources) be reduced below that required to maintain at least 40 F in the building. Electric Motors and Machinery . Motors and the machinery which they drive, if both are located in the room, convert all of the electrical energy supplied into heat, which is retained in the room if the product being manufactured is not removed until its temperature is the same as the room temperature. If power is transmitted to the machinery from the outside, then only the heat equivalent of the brake horsepower supplied is used. In the first case the Btu supplied per hour = horsepower x 2546, and Efficiency of motor . in the second case Btu per hour = bhp X 2546, in which 2546 is the Btu equivalent of 1 hp-hr. In some mills this is the chief source of heating and it is frequently sufficient to overheat the building even in zero weather, thus requiring cooling by ventilation the year round. . The heat (in Btu per hour) from electric lamps is obtained by multi plying the watts per lamp by the number of lamps and by 3.415. One cubic foot of producer gas gives off about 150 Btu per hour; one cubic foot of illuminating gas about 535 Btu per hour; and one cubic foot of natural gas about 1000 Btu per hour. A Welsbach burner averages 3 cu ft of gas per hour and a fish-tail burner, 5 cu ft per hour. For information concerning the heat supplied by persons, see Chapter 3. : In intermittently heated buildings, besides the capacity necessary to care for the normal heat loss which may be calculated according to customary rules, additional capacity should be provided to supply the heat necessary to warm up the cold material of the interior walls, floors, and furnishings. Tests have shown that when a cold building has had its temperature raised to about 60 F from an initial condition of about 0 F, the heat absorbed from the air by the material in the structure may vary from 50 per cent to 150 per cent of the normal heat loss of the building. It is therefore necessary, in order to heat up a cold building within a reasonable length of time, to provide such additional capacity. If the 135 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 SOUTH eumnoM 136 CHAPTER 7. HEATINC LOAD interior material is cold when people enter a building, the radiation of heat from the occupants to the cold material will be greater than is normal and discomfort will result. (See Chapter 3.) - RESIDENCE HEAT LOSS PROBLEMS Example 2. Calculate the heat loss of residence shown in Fig. 1 located in the vicinity of Chicago. Assume inside and outside design temperatures to be 70 F and. --10 F respectively. The attic is unheated. Assume ground temperature to be 45 F. Estimate infiltration by crack method, assuming average wind velocity to be 12.5 mph during December, January and February. No wall, ceiling or roof insulation is to be figured in this problem, but all first and second floor windows are to have storm sash. The building is constructed as follows (transmission coefficients {U) in parentheses): .. Walls: Brick veneer, building paper, wood sheathing, studding, metal lath and plaster ' (0 28). Walls of dormer over garage, same except wood siding in place of brick veneer (0-26)* Attic Walls: Brick veneer, building paper, wood sheathing on studding (0.42). Basement Walls: 10 in. concrete (0.70). - Roof: Asphalt shingles on wood sheathing on rafters (0.56). Ceiling: (Second floor): Metal lath and plaster (0.69). ,. Windows: Double-hung wood windows with storm sash (0.45). Steel casement sash in basement (1.13). . ............ Floor {Bedroom D): Maple finish flooring on yellow pine sub-flooring; metal lath and plaster ceiling below (0.25). Floor {Basement and Garage): 4 in. stone concrete on 3 in. cinder concrete (0.64). Solution: The calculations for this problem are given in Table 3, and a summary of the results in Table 4. The values in column F of Table 3 were obtained by multiplying together the figures in columns C, D and E. The heat losses are'calculated to the nearest 10 Btu. See reference notes for Table 3 for further explanation of data. Attention is called to the summary of heat losses (Table 4) of the uninsulated residence (Fig. 1). As storm windows are used in this instance the glass and door trans mission heat losses of 19.5 per cent are relatively small.. The infiltration losses (12.0..... per cent) are also comparatively small in this case because the storm windows serve substantially the same purpose as weatherstripping. In this problem, the wall, ceiling and floor transmission losses comprise 68.5 per cent of the total. If the building is : insulated, the relative heat loss percentages will materially change. (See Example '3 1 and Table 5.) . Example 3, Calculate the heat loss of residence shown , in Fig. 1 based-on the - same conditions as in Example 2 but insulated throughout as follows (coefficients in parentheses): Walls: Brick veneer, 2%i2 >n- insulation board sheathing, studding, 1 in. insulation board lath and plaster (0.14). Walls of dormer over garage same except wood siding in place of brick veneer (0.13). ... .. . Attic Walls: Brick veneer, 2^2 in. insulation board sheathing on studding (0.28). Walls Adjoining Garage: Plaster on 1 in. insulation board, studding, metal lath and ` plaster (0.18). Basement Walls {Recreation Room): 10 in. concrete,-furring.strips, in. insulation . board (0.26). Roof: Asphalt shingles on wood sheathing on rafters (0.56). ' Ceiling {Second floor): 1 in. insulation board and plaster; top of ceiling joists (0.15). in. insulation board on" Windows: Same as Example 2. ..... . . ........ Floor {Bedroom D): Maple finish flooring on yellow pine sub-flooring; Yi in. insulation board and plaster ceiling below (0.18). ., Floor {Under Recreation Room): 4 in. stone concrete, 1 in. insulation board and 3 in. ` cinder concrete (0.22). ' Solution: The procedure for calculating the heat losses is similar to that for Example 2. A summary, of the results is given in Table 5.... ............... ................................... ......... 137 4s U i HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 3 Heat Loss Calculation Sheet for Uninsulated Residence (Fig. 1) A Room ob Space B Part op Structure c DE F G Net Area or Coeffi Temp. Heat Loss Totals Crack Length cient Diff. (Btu per hour) (Btu per hour) Bedroom A Walls Glass Infiltration Ceiling*1 238 sq ft 40 sq ft 36 lin ftb 242 sq ft Bedroom B and Closet Walls Glass Infiltration Ceiling*1 156 sq ft 40 sq ft 36 lin ft*= 160 sq ft Bedroom C Walls Glass Infiltration Ceiling*1 114 sq ft 27 sq ft 18 lin ftf 120 sq ft Bedroom D and Closet Walls Glass Infiltration Ceiling*1 Floor over Garage 118 sq ft 20 sq ft 18 lin ft 120 sq ft 110 sq ft Bathroom 1 Walls Glass Infiltration Ceiling*1 30 sq ft 14 sq ft 18 lin ft 55 sq ft Bathroom 2 Walls Glass Infiltration Ceiling*1 . Floor over Garage 79 sq ft 9 sq ft 151 lin ft 35 sq ft 35 sq ft Living Room Walls Walls (adjoining garage) Glass Infiltration 267 sq ft 94 sq ft 50 sq ft 40 lin ft Dining Room Walls Glass (doors) Glass (window) Infiltration1 . 166 sq ft 35 sq ft 20 sq ft 31 tin ft Kitchen and Entrance to Garage Walls (outside) Walls (adjoining garage) Infiltration Glass Door to garage 96 sq ft 51 sq ft 27 sq ft 18 lin ft 17 sq ft Lavette and Vestibule Walls (outside) Walls (adjoining garage) Door Glass Infiltration 82 sq ft 85 sq ft 19 sq ft 9 sq ft 19 lin ft 0.28 0.45 0.35c 0.69 80 80 80 39.8 0.28 0.45 0.35 0.69 80 80 80 39.8 0.28 0.45 0.35 0.69 80 80 80 39.8 0.28 0.45 0.35 0.69 0.25 80 80 80 39.8 35R 0.28 0.45 0.35 0.69 80 80 80 39.8 0.26 0.45 0.35 0.69 0.25. 80 80 80 39.8 35 0.28 0.39h 0.45 0.35 80 35 80 80 0.28 1.13 0.45 0.35 80 80 80 80 0.28 0.39h 0.35 0.45 0.51 80 35 80 80 35 0.28 0.39h 0.51 0.45 0.35 80 35 80 80 80 5330 1440 1010 6660 3490 1440 1010 4400 2560 970 500 3300 2650 720 500 3300 960m 670 500 500 1510 1770 320 420 960 310m 5980 1280" 1800 1120 3720 ' 3160 . 720 870 2150 700" 760 650 300" 1840 1160" 780 320 530 14,440 10,340 7,330 8,130 3,180 3,780 10,180 8,470 4,560 4,630 138 CHAPTER 7. HEATING LOAD Table 3. Heat Loss Calculation Sheet for Uninsulated Residence (Fig. 1) (Concluded) A Room or Space B Part of Structore C DE F G Net Abba or Crack Length Coeffi cient Temp. Dip.* Heat Loss Totals (Btu per hour) (Btu per hour) Entrance Hall Walls Door Infiltration Ceding*1' P Garage Walls Glass Doors Infiltration Floor (heat gain) Heat gain Recreation0 Room Floor Walls Glass Infiltration Total 39 sq ft 21 sq ft 20 lin ft 87 sq ft 167 sq ft 53 sq ft 44 sq ft 37 lin ft 185 sq ft 287 sq ft 220 sq ft 8 sq ft 8 lin ft 0.28 0.38 0.35 0.69 80 80 80 39.8 870 640 560 2490 0.28 45 1.13 45 0.51 45 1.62i 45 0.64>* -10k 2110 2700 1010 2700 -1180 -4710" 0.64 0.70 1.13 0.76 25 25 80 80 . .4600 3850 720 490 4,560 2,630 9,660 91,890 The inside-outside temperature difference is 70 - (-10) or 80 F, except where otherwise noted. bOnly the south windows are used for arriving at the window crack for this room, on the assumption that whatever air enters through the south window cracks will leave through the west window cracks or elsewhere. . ... cDouble-hung wood windows with storm sash are assumed to have the same leakage per foot of crack as weatherstnpped windows. The air leakage per foot of crack is about 19.5 cu ft per foot of crack for a wmd velocity of 12.5 mph. (See Table 2, Chapter 6.) The heat equivalent of the air leakage per hour per temperature difference per foot of crack is obtained by multiplying this value by 0.018. or 19.5 X 0.018 = 0.35. ' din this problem the ceiling heat losses are calculated by estimating the attic temperature and then calculating the loss through the ceUing using the proper temperature difference. This unheated attic is not ventilated during the winter months. The attic temperature is estimated from Equation 1 to be 30.2 F when the outside temperature is -10 F and the room temperature is 70 F. The temperature difference is therefore 70 -- 30.2 or 39.8 F. The window crack in.the west wall having two windows is used. fQne-half the total crack is used in these rooms. ^Temperature in garage assumed to be 35 F. . etudsCOC(ud=no 39r)WaU adiining garage calculated on basis of metal lath and plaster on both sides of ,iTh5 door crack is used for estimating the infiltration in this room and as the French doors are weatherstripped the infiltration coefficient is assumed to be the same as in Note b. r *lSkagr/or thfe garacge dooria assumed to be twice that for poorly-fitted double-hung wood windows 0 018 X 90 or 162^f00t f crack for a wlnd veloclty of 12.5 mph. The infiltration coefficient is therefore ground temperature is assumed to be 45 F and as the garage temperature is 35 F. the heat transfer wui be from the ground to the garage, and this heat gain should therefore be subtracted from the heat loss. Aae ,jr coefficient (U *= 0.64) is based on 4 in. stone concrete and 3 in. cinder concrete. This coefficient snould probably be lower as the ground itself has some heat resistance value. However, complete data are not as yet available. "The heat losses from various rooms into the garage are heat gains for the garage. , "Heat is to be provided for the recreation room and this space is therefore figured on the basis of a 70 F wmperature. Heat loss into the basement from recreation room is neglected, the calculations being based niy on losses through the outside wails, glass and floor. Ground temperature assumed to be 45 F. pThe upstair hall ceiling is included with the downstairs entrance hall because these are connected by means of the stairway. The heat should be provided downstairs. 139 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 4. Summary Of Heat Losses Of Uninsulated Residence Heat losses given in Btu per hour _Room ob Space Walls Ceiling and .Roof Floor Glass and Dooa Infiltration Totals Bedroom A ` ' ' ` 5330 Bedroom B------ - 3490 Bedroom C 2560 Bedroom D ' 2)650 Bathroom 1 670 Bathroom 2 1770 Living Room 7260 Dining Room . 3720 Kitchen . : 2850 ' Lavette 3000 Entrance Hall 870 Garage V -1030* Recreation .t:. 3850 Totals | ` 36,990 Percentages 40.2 6660 4400 3300 3300 1510 960 2490 22,620 24.6 960 310 --2450f : 4600 3,420 3.7 1440 1440 970 720 500 320 1800 3880 950 1100 640 3410 720 17,890 19.5 .. Wall Heat.loss of 2110 Btu.minus wall heat gain of 3140 Btu. tHeat gains; 960, 310 and 1180 Btu. 1010 1010 500 500 500 420 1120 870 760 530 560 2700 490 10,970 12.0 14,440 10,340 7,330 8,130 3,180 3,780 10,180 8,470 4,560 4,630 4,560 2,630 9,660 91,890 - 100.0 Table 5. Summary of Heat Losses of Insulated Residence Heat losses given in Btu per hour Room ob Space Walls Ceiling and Roof Floor . Glass and Door Inpiltbati'on Totals Bedroom A Bedroom B Bedroom C Bedroom D Bathroom 1 Bathroom 2 Living Room Dining Room Kitchen Lavette .Entrance HaH Garage Recreation Totals Percentages 2670 1750 1280 1320 340 820 3580 1860 1400 1460 440 -400* 1430 17,950. 32.5 2370 1570 1170 1170 540 340 6) 220 850 ------- * 8,010 14.5 --2090f 1580 400 0.7 1440 1440 970 720 500 320 1800 3880 950 1100 640 3410 720 17,890 32.4 1010 1010 500 500 500 420 1120 870 760 530 560 2700 490 10,970 19.9 7,490 5,770 3,920 4,400 1,880 2,120 , 6,400 6,610 3,110 3,090 2,490 3,620 4,220 55,220 100.0 Wall* heat loss of 1050 Btu minus* wall* heat gains of 590. 320 and 540 Btu. ' tHeat gains; 690, 220 and 1180 Btu. 140 Chapter 8 COOLING LOAD , -Conditions of Comfort, Design Outside Temperatures Com ponents of Heat Gain, Normal Heat Transmission, Solar Heat Transmission, Sun Effect Through Windows, Heat Emission of Occupants, Heat Introduced by Outside Air, Heat Emission of Appliances LOAD calculations for summer air conditioning are more complicated than heating load calculations because there are more factors to be considered. Due to the variable nature of some of the contributing load components and the fact , that they do not necessarily impose their maximum effect simultaneously, considerable care must be used in determining their phase relationship so that equipment of proper capacity may be selected to maintain specified indoor conditions. The conditions to be maintained in an enclosure are variable and depend upon several factors, especially the outside design conditions, duration of occupancy and relationship between air motion, dry-bulb and wet-bulb temperatures. Information concerning the proper effective temperature to be maintained is given in Chapter 3,. where are also tabu lated the most desirable indoor conditions to be maintained in summer for exposures over 40 min (see Table 5, Chapter 3). Summer dry-bulb and wet-bulb temperatures of various cities are given in Table 1. The temperatures are not the maximums but the design temperatures which should be used in air conditioning calcu lations. The maximum outside wet-bulb temperatures as given in Weather Bureau reports usually occur only from 1 to 4 per cent of the time, and they are therefore of such short duration that it is not practical to design a cooling system for them. The temperatures shown in Table 1 are based on available design conditions known to be successfully applied. COMPONENTS OF HEAT CAIN A cooling load determination is composed of five components which are classified in the following manner: * 1. Normal heat transfer through windows, walls, partitions, doors, floors, ceilings, etc. 2. Transfer of solar radiation through windows, walls, doors, skylights, or roof. 3. Heat emission of occupants within enclosures. 4. Heat introduced by infiltration of outside air or controlled ventilation. 5. Heat emission of mechanical, chemical, gas, steam, hot water and electrical appliances located within enclosures. 141 HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 TABLfe 1. Design Dry- and Wet-Bulb Temperatures, Wind Velocities, and Wind Directions for June, July, August, and September Stats ClTT Design Drt-Bulb Design Wet-Bulb Summer Wind Velocttt MPH Prevailing Sumher Wind Direction Ala................. Birmingham............... Mobile.......................... Ariz...... _....... Ark................. calif.............. Phoenix.................... -- Little Rock................. Los Angeles..............,, San Francisco............. Colo--........... Conn....... ...... Dela--..... ... D. C.............. Fla.................. Denver......................... New Haven................. Wilmington................. Washington................. Jacksonville,................ Tampa.......................... Ga....... -....... Atlanta......................... Savannah--..............-- Idaho_______ 111............ Ind-------------Iowa------------ Boise--.......................... Chicago__________ --- Peoria........-........ ......... Indianapolis.--........... Des Moines......... ....... Kansas-------- Wichita......... .............. Ky-........ ....... Louisville................-- La................... New Orleans.............. Shreveport.---......................... Maine-......... Portland........... ......................... Md-------------- Baltimore-............................... Mass.............. Boston....................................... Mich.............. Detroit......-............................... Minn Minneapolis.................... -- Miss------------ Vicksburg.--............ ................ Mo--........... .. Kansas City.--......... .... St. Louis........ ........................... Mont............. Helena................... -.................. Nebr.............. Lincoln............................ ......... Nev---- -------- N. H............- N. J~ N. Y, Reno.....-...... ...... ..............-....... Manchester--.......... .............. Trenton................................ --Albany......... ............................ Buffalo.......... -.......................... New York................................ N. M, N. C. Santa Fe...............--........ -..... Asheville--............. ............... Wilmington........................... N. Dak_____ Bismarck........... Ohio...... ........ Cincinnati.......... Cleveland--------- Okla------------ Oklahoma City. Oreg--......... Portland-........ .. Pa................... Philadelphia___ Pittsburgh-------- R. I................ Providence____ S. C................ Charleston......... Greenville______ S. Dak..... ..... Sioux Falls_____ Tenn.............. Chattanooga..... Memphis............ 95 95 105 95 90 90 95 ' 95 95 95 95 94 95 95 95 95 95 95 95 100 95 95 100 90 95 92 95 . 95 95 100 95 95 95 95 90 95 92 93 95 90 90 95 95 95 95 101 90 95 95 93 95 95 95 95 95 78 80 76 78 70 65 64 75 78 78 78 79 76 78 65 75 76 76 77 75 76 79 78 73 78 75 75 75 78 76 78 67 75 65 73 78 75 75 75 65 75 79 73 78 75 76 65 78 75 75 80 76 75 77 78 5.2 8.6 6.0 7.0 6.0 11.0 6.8 7.3 9.7 6.2 8.7 7.0 7.3 7.8 5.8 10.2 8.2 9.0 6.6 11.0 8.0 7.0 6.2 7.3 6.9 9.2 10.3 8.4 6.2 9.5 9.4 7.3 9.3 7.4 5.6 10.0 7.1 12.2 12.9 6.5 5.6 7.8 8.8 6.6 9.9 10.1 6.6 9.7 9.0 10.0 9.9 6.8 7.6 6.5 7.5 S SW W NE SW SW S S SW S SW E NW SW NW NE S SW SW S SW SW S S SW SW SW SE SW S SW SW s w NW SW s SW SW SE SE SW NW SW S s NW SW NW NW SW NE S SW SW 142 CHAPTER 8. COOLING LOAD Table 1. Design Dry- and Wet-Bulb Temperatures, Wind Velocities, and Wind Directions for June, July, August, and September (Concluded) State Crrr Design Drt-Bulb Desiok Wet-Bulh Summer Wind Velocitt MPH Prevailing Summer Wind DjBECTKMf Texas. Dallas..................:.................... . 100 78 9.4 S El Paso.--............................... 100 69 6:9 E Galveston--............................ 95 80 9.7 S Houston--........... -.................. 95 San Antonio............................. 100 78 78 7.7 S 7.4 SE Utah...... Salt Lake City........................ 92 63 8.2 SE Vt--------- Burlington................................ 90 73 8.9 S Va.......... Norfolk.--................................. 95 78 10.9 S Richmond................................ 95 78 6.2 SW Wash..... . Seattle...................................... 85 65 7.9 S Spokane.......... ......................... 90 65 6.5 SW W. Va..... Wise------ Wyo____ Parkersburg-.......................... Madison.......... ......................... Milwaukee-............................. Cheyenne-...............--......... .. 95 95 95 95 75 75 75 65 5.3 8.1 10.4 9.2 SE SW S S The components of heat gain, classified by source are further classified as sensible and latent heat gain. The first two components fall into the classification of sensible heat gain, that is, they tend to raise the temperature of the air within the structure. The last three components not only produce sensible heat gain but they may also tend to increase the moisture content of the air within the structure. Normal Heat Transmission By normal heat transmission, as distinguished from solar heat trans mission is meant the transmission of heat through windows, walls, partitions, etc. from without to interior of enclosure by virtue of difference between outside and inside air temperatures. This load is calculated in a mariner similar to that described in Chapter 7 (except that flow of heat is reversed) by means of the formula: where flt = A U (L, - I) (1) ui -- iicul Liaiisinuiea xnrougn tne material ot wall, glass, floor, etc., Btu per hour. A = net inside area of wall, glass, floor, etc., square feet, f = inside temperature, degrees Fahrenheit. to = outside temperature, degrees Fahrenheit. U = coefficient of transmission of wall, glass, floor, etc., Btu per hour per square foot per degree Fahrenheit difference in temperature (Tables 3 to 13, Chapter 5). Solar Heat Transmission Calculations of the solar heat transmitted through walls and roofs axe difficult to determine because of periodic character of heat flow and time lag due to heat capacity of construction. . 143 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 The variation in solar intensity is given in Fig. 1. The curves are drawn from A.S.H.V.E. Laboratory data obtained by pyrheliometer, are based on sun time, and apply for a perfectly clear day on August 1 at a north latitude of 40 deg. A study of these curves discloses the periodic relationship and wide variation in solar intensity on various surfaces. It will be observed that both the roof (horizontal surface) and south wall radiation curves are in exact phase relationship with each other and that whereas the east and west wall radiation curves overlap those for roof and south wall, they do not overlap each other. This phase relation ship has an important bearing on the cooling load. Failure to consider the periodic character of heat flow resulting from diurnal movement of the sun and the lag due to heat capacity of the structure, which determine the timing and magnitude of the heat wave flowing through the wall, may result in a large error in load calculations. CHAPTER 8. COOLING LOAD ______ _ aoainst walls having sev and a Horizontal Surface. For SO Deg Latitude on the twenty-first of July. Intensity of Solar Radiation, Btu per Sq Ft per Hour Fig. 1. Curves Giving Solar Intensity Normal to Sun, on Horizontal Surface and on Walls for August 1 . The values of solar intensity appearing in Fig. 1 must not be confused with the actual heat transmission through the wall for much of the solar radiation impinging against the outer surface fails to pass through the wall. Instead it is delivered to the outside air by reflection, radiation, convection and conduction. A mathematical solution for the deter . mination of solar heat transmission has been developed but the equations involved are too complex for practical application.1 From results of this investigation and earlier studies,2 the Research Laboratory has prepared Tables 2, 3, 4 and 5 which give the solar intensity (7) for various hours of the day on walls of various orientations and horizontal surfaces. These values are shown for north latitudes from 30 to 45 deg. 1A.S.H.V.E. Research Report No. 923--Heat Transmission as Influenced by Heat Capacity and Solar Radiation, by F. C. Houghten, J. L. Blackshaw, E. W. Pugh and Paul McDermott(A.S.H.V.E. Transactions, Vol. 38. 1932, p. 231). *A.S.H.V.E. Research Report No. 853--Absorption of Solar Radiation in its Relation to the Tem perature. Color, Angle and Other Characteristics of the Absorbing Surface, by F- C, Houghten and Carl Gutberiet (A.S.H.V.E. Transactions. Vol. 36, 1930, p. 137). 144 Table 3. Solar Radiation Impinging against Walls having several Orientations, and a Horizontal Surface. For 85 Deg Latitude on the twentyfirst of July. Sun Time 4:46 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 1:00 2:00 3:00 4:00 5:00 6:00 7.-00 7:14 0 9 67 142 150 118 60 2 Intensity of Solar Radiation. Btu per Sq Ft per Hour --------1-------------- ------- East South: 00 93 72 35 174 103 209 145 191 154 143 139 75 103 55 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 4. Solar Radiation Impinging against Walls having several Orientations, and a Horizontal Surface. For 40 Deg Latitude on the twenty-first of July. Sun Tims Northeast 4:31 5:00 6:00 7:00 8:00 0 14 72 143 143 9:00 10:00 11:00 12:00 ) -no ?-oo von 4.-00 104 46 voo 6:00 7:00 7:29 Intensity of Solar Radiation. Btu per Sq Ft per Hour East 0 14 80 180 211 192 143 75 Southeast South Southwest West Northwest Horizontal Surface 0 5 40 112 155 8 0 :. 1 19 82 152 168 46 156 77 121 95 73 103 15 73 15 95 : 121 75 77 156 143 46 46 168 192 104 8 155 211 143 213 268 284 293 284 258 213 152 112 180 143 ' 40 80 72 5 14 14 000 82 19 1 0 Table 5. Solar Radiation Impinging against Walls having several Orientations, and a Horizontal Surface. For Ifi Deg Latitude on the twenty-first of July. SUN Time Northeast 4:26 5:00 6:00 7:00 8:00 0 ! 25 89 149 140 9:00 10:00 11:00 12:00 . 92 33 i -no 7-00 .1:00 4:00 ^00 dioo 7.-00 Intensity of Solar .Radiation, Btu pbr-Sq Ft per Hour East Southeast South Southwest West Horizontal Northwest Surface 00 24 9 99 52 194 125 219 171 194 183 i44 171 75 139 ; 91 22 .65 98 121 128 32' 91 0 210 251' 274 . 282 ' 32 121 139 98 171 65 183 22 , 171 75 . 144 33 194 92 219 140 274 251 210. 156 ' 125 194 144 52 99 89 9 24 25 90 26 .2 146 CHAPTER 8. COOLING LOAD Since the amount of solar intensity actually transmitted through a surface depends^ upon the nature of the exterior surface of wall of roof construction, it is necessary, in order to determine actual amount of solar heat transmission, to apply correction factors to the values of (i). Solar radiation factors and solar absorption coefficients have been determined8 as indicated in Fig. 2 and Table 6 respectively. The solar heat conduction through a wall or roof exposed to the sun may be expressed by the formula: where HR = A Fa I . (2) Hr = solar heat transmission, Btu per hour. A -- area of wall or roof, square feet. ., F = radiation factor--percentage (expressed as a decimal) of the absorbed solar radiation which is transmitted to the inside (Fig. 2). a = absorption coefficient--percentage (expressed as a decimal) of the incident solar radiation which is absorbed by the surface (Table 6). I -- intensity of solar radiation striking surface, Btu per hour per square foot (Tables 2, 3, 4 and 5). The total amount of heat conducted through a wall exposed to the sun is the sum of Ht and HR from Formulas 1 and 2. *A Rational Heat Gain Method for the Determination of Air Conditioning Cooling.Loads, by F. H. Faust, L. Levine, and F. O. Urban (A.S.H.V.E. Transactions, Vol. 41, 1935, p. 327). ' . 147 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 6. Solar Absorption Coefficients for Different Building Materials Si/reace Material Absorption Coefficient <o> White stone Very Light Colored Surfaces..... ...... Very light colored cement ; White or light cream-colored paint 0:4 Asbestos shingles Unpainted wood II Brown stone Medium Dark Surfaces............. ...... Brick and red tile Dark-colored cement ' 0.7 Stucco .. Red, green or gray pamt Slate roofing Very Dark Colored Surfaces-.. ...... Tar roofing materials Very dark paints 0.9 The calculation of heat transmission through walls and roofs does not take into consideration the heat capacity of the structure nor the con sequent time lag in the transmission of heat. In the case of massive walls the time lag may amount to several hours4. Thus in many cases the wall transmission cannot be added directly to.the cooling load from other sources because the peak of the wall transmission load may not coincide with the peak of the total cooling load and may even occur after the cooling system has been shut down for the day. The data in Table 7 were taken from A.S.H.V.E. research papers and whereas they result from a study of experimental slabs, they give an approximate idea of the time lag to be expected in various structures. Solar Radiation Transmitted Through Glass Windows present a problem somewhat different from that of opaque walls, because they permit a large percentage of the solar energy to pass through, a small amount is reflected and the balance is absorbed by the glass. The amount absorbed depends upon the character and thickness of the glass and the angle between it and the sun's rays. The temperature of the glass is raised by the absorbed heat and this heat is then delivered to the air on each side in proportion to the difference between the glass and air temperatures.5 Table 7. Time Lag in Transmission of Solar Radiation through Walls and Roofs Ttpb an Thickness of Wall or Roof Torn Lao, Boras 2-in. pine----------------------------------------- -.................... -.............................. 3-in. concrete and 1-m. cork.--------- ............................ .. . n ,r 2-in. iron and cork (equivalent to 54-.il ............... 4-in. iron and cork (wtuyatent to 5^m. cono^ 1^-m- - 8-in. iron and cork (equivalent to 16-in. concrete ana 1.00 in. cor*/......... m 3 2H 2 2H 754 19 10 ^TatAWbS Gta Windows, by W. W. Shaver (A.S.H.V.E. Transactions, Vol. 41. 1935. p. 287). 148 CHAPTER 8.. COOLING LOAD The A.S.H.V.E. tests6 indicate that a single pane of double strength glass 0.127 in. thick absorbs.approximately 11 per cent of the solar radiation passing through it when the impingement is-normai. For smaller angles of impingement, the glass,;retards percentages of the total radiant energy approximately in proportion to. the sine of the angle. . . The amount of solar radiation delivered to an unshaded glass surface may be obtained from Tables 2, 3, 4 or 5. These values must .be used only for the net glass area, on which the sun shines and not the entire glass; area. Tests at the A.S.H.V.E. Research Laboratory7 have determined the percentage of heat from solar radiation actually delivered to a room, with various types of outdoor and indoor shading. The data in Table 8. are taken from these tests. . The percentage values in this table were obtained by dividing the total amount of heat actually entering through' the shaded window by the total amount of heat calculated to enter through a bare window (solar radiation plus glass transmission, based on observed outside glass tem perature). For bare windows on which the sun shines, the transmission of heat from outside air to glass may be small or negative as the glass temperature is raised by the solar radiation absorbed. . In calculating the total heat gain through windows on the sunny side of buildings, it is sufficiently accurate to proceed as follows: Consider the total heat gain as that resulting from solar radiation and neglect the heat transmission through the glass caused by the difference between the temperatures of the inside and outside air. This method should be used except at times when the calculated heat gain per square' foot due to normal .transmission exceeds the solar intensity. At such times, solar radiation may be neglected and. the total, heat gain considered as resulting from normal transmission. The solar heat transmission through windows or skylights may be expressed by the formula: where ffo = AofI (3) Ho = solar radiation transmitted through a window, Btu per hour. - Ag -- net area of glass exposed to sun's rays, square feet. / -- percentage of solar radiation (expressed as a decimal) transmitted to. the, inside (Table 8). For bare windows, / * 1. .. . . ' 7 intensity of solar radiation striking surface, Btu per hour per square foot] (Tables 2, 3, 4 and 5). ...... In Equation 3, / = 1 for bare windows because the tests from which Table 8 was obtained showed that approximately all of the solar, radiation] impinging on a bare window .became a part of the heat load in the room.-. This was because almost all- of the heat absorbed by the glass flowed into the room by conduction. Other tests8 have indicated that in the case of A.S.H.V.E. Research Report No. 974---Radiation of Energy Through Glass, by J. L. Blackshaw and F. C. Houghten (A.S.H.V.E. Transactions, Vol. 40.1934, p. 93). A.S.H.V.E Research Report No.975 --Studies of Solar Radiation Through Bare and Shaded Windows by F. C. Houghten, Carl Gutberlet, and J. L. Blackshaw (A.S.H.V.E. Transactions, Vol. 40, 1934, p. 101). . rLoc. Cit. Note 6. *A.S.H.V.E. Research Report No. 1002--Cooling Requirements of Single Rooms in a Modern Office Building, by F. C- Houghten, Carl Gutberlet, and Albert J. Wahl (A.S.H.V.E. Transactions, Vol. 41, 1935, p. 53). 149 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 a building having floors of high heat capacity such as concrete floors on which the solar radiation falls, approximately one-half of the heat entering a bare window is absorbed by the floor and does not immediately become a part of the cooling load, but is delivered back to the air in the building at a slow rate over a period of 24 hr or longer. The maximum solar intensity on any surface is of limited duration as shown in Fig. 1. In the case of windows the total energy impinging on the glass before and after the time of maximum intensity is further reduced by increased shading of the glass from the frame, or wall. The cooling load due to solar radiation therefore does not have to be calculated as a steady load. Another point which should be noted is that the maximum solar radiation load on the east wall occurs early in the morning when the outside temperature is low. Tests have been made which indicated that solar radiation through window glass is the most important factor to contend with in the cooling of an office building. At times it was shown to account for as much as Table 8. Solar Radiation Transmitted through Shaded Windows Ttpb*of Afpubtbhancb Finish Facing Sun Inside shade, fully drawn........... ..................... ................................... Inside shade, one-half drawn............................ ................................... Inside Venetian blind, fully covering window, slats at 45 deg. Outside Venetian blind, fully covering window, slats at 45 deg__ Aluminum Buff Aluminum Aluminum Pxb Cent Deliteisd to Room 28 22 45 68 58 22 75 per cent of the total cooling necessary. Because of the importance of the sun load, cooling systems should be zoned so that the side of the building on which the sun is shining can be controlled separately from the other sides of the building. If buildings are provided with awnings so that the window glass is shielded from sunshine, the amount of cooling required will be reduced and there will also be less difference in the cooling requirements of different sides of the building. The total cooling load for a building exposed to the sun on more than one side is of course less than the sum of the maximum cooling loads in the individual rooms since the maximum solar radiation load on the different sides occurs at different times. In determining the total cooling load for a building if the time when the maximum load occurs is not obvious, the load should be calcu lated for various times of day to determine the times at which the sum of- the loads on the different sides of the building is a maximum. Heat Emission of Occupants The heat and moisture given off by human beings under different states of activity are shown in various tables and figures of Chapter 3 which covers the physical and physiological principles of air conditioning. It will be observed from these data that the rate of sensible and latent heat emission by human beings varies greatly depending upon state of activity. In many applications this component 'becomes a large pier- 150 CHAPTER 8. COOLING LOAD centage of total load. Metabolic rates are markedly variable for some extreme environmental conditions and this is another important factor which must be considered in cooling load computations. Heat Introduced by Outside Air An allowance must be made for the heat and moisture in .the outside air introduced for ventilation purposes or entering the building through cracks, doors, and other places where infiltration might occur. The volume of air entering due to infiltration may be estimated from . data given in Chapter 6. Information on the amount of outside air required for ventilation will be found in Chapter 3. In the event the volume of air entering an enclosure due to infiltration exceeds that required for ventilation, the former should be used as a basis for determining the portion of the load contributed by outside air. Where volume of air required for ventilation exceeds that due to infiltration it is assumed that a slight positive pressure will exist within the enclosure with a resulting exfiltration instead of infiltration. In this case the air required for ventilation is used in determining outside air load. . The sensible heat gain resulting from the outside air introduced may be determined by the following formula: ' Hi = 0.24 X 60 do Q (to - t) . (4) where Hs = sensible heat to be removed from outside air entering the building, Btu per hour. Q = volume of outside air entering building, cubic feet per minute, do = density of air, pounds of dry air per cubic foot at temperature to. to = temperature of outside air, degrees Fahrenheit. t = temperature of inside air, degrees Fahrenheit. The total heat gain resulting from outside air introduced may be deter mined by the following formula: * H = 60 do Q {ho - h) (5) where H = total heat to be removed from outside air entering the enclosure, Btu per hour. Q = volume of outside air entering enclosure, cubic feet per minute. do = density of air, pounds of dry air per cubic foot of air (at temperature to). . ho = heat content of mixture of outside dry air and water vapor, Btu per pound of dry air (at temperature to). h = heat content of mixture of inside dry air and water vapor, Btu per pound of dry air (at temperature t). ~ The latent heat gain resulting from outside air introduced may be determined by the following formula: '. where Hi = H - Ha Hi = latent heat to be removed, Btu per hour. H total heat to be removed, Btu per hour. Hs = sensible heat to be removed, Btu per hour. 151 .. . . . . .. (6) HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 10. Heat Gain from Various Sources . . Source Btu Per Hour J jSensible Latent Total Electric Heating Equipment_________ Electrical Equipment--Dry Heat--No Evaporated Water-----~---------------- ------ Electric Oven--Baking.......................................... .......----------- ---------------------- -------------------Electric Equipment---Heating Water--Stewing, Boiling, etc---------------------------------Electric Lights and Appliances per Watt (Dry Heat)-------------------------- -------------------Electric Lights and Appliances per Kilowatt (Dry Heat)---------------------------- ------ -- Electric Motors per Horsepower------ ---------------------------------------------------------- --------- -----Electric Toasters or Electric Griddles.------------------------------------------- .----------- ----- ---------Coffee Urn--Large. 18 in. Diameter--Single Drum----------------- -- ------------------ ----Coffee Urn--Small. 12 in. Diameter--Single Drum-------------- --------------------------------Coffee Urn--Approx. Connected Load per Gallon of Capacity------------------------ -- Electric Range--Small Burner----------- ------------- ------------------------------------ --....................... Electric Range--Large Burner.________________________________________________ ______ Electric Range--Oven._------------------- ---------------- ------.-------------------------------------- ------------Electric Range--Warming Compartment---------------------------------------- --------- ---------Steam Table--Per Square Foot of Top Surface------------------------------------ ------------ -----Plate Warmer--Per Cubic Foot of Volume------------------------------------ ,-------------------------Baker's Oven--Per Cubic Foot of Volume---------------------------------------------------------------Frying Griddles--Per Square Foot of Top Surface.---------------------------- ----------......... Hot Plates--Per Square Foot of Top Surface----------------------------------------------------------Hair Dryer in Beauty Parlor--600 w.,,................ ......................................... ...............--........ Permanent Wave Machine in Beauty Parlor--24-25 w Units---------------........ 100% 80% 3.4 3413 2546 0% 2000 1200 600 .* * 8000 ` 1025 300 850 3200 * * 2050 2050 o% 20% 50% 0 0 0 10% 2000 1200 600 * * 2000 0 800 0 1300 * * 0 0 100% 100% 100% 3.4 3413 2546 100% 4000 2400 1200 3400 7500 10000 1025 1100 850 4500 4600 0000 2050 2050 Gas Burning Equipment Gas Equipment--Dry Heat--No Water Evaporated---------------------------------------------- eo% Gas Heated Oven--Baking---------- ----- ---------------- -------- ----------------------------------------------- 67% Gas Equipment--Heating Water--Stewing. Boiling, etc------------------ ---........ .......-- 50% Stove, Domestic Type--No Water Evaporated--Per Medium Size Burner--------- 9000 Gas Heated Oven--Domestic Type------------------------------------------------------ -------- ------------- 12000 Stove. Domestic Type--Heating Water--Per Medium Size Burner.. Residence Gas Range--Giant Burner (About 5H in. Diameter)------.-------------------Residence Gas Rauge--Medium Burner (About 4 in. Diameter)------ ----------- ---- Residence Gas Range--Double Oven (Total Size 18 in. x 18 in. x 22 in. High)-------- Residence Gas Range--Pilot--------------- --------------------------------------------------------------- -----Restaurant Range--4 Burners and Oven-------------------- ---------------------------------------------Cast-Iron Burner--Low Flame--Per Hole------------- --.----- -------- ----------- --------Cast-iron Burner--High Flame--Per Hole.---------- ------ ------------------------------...--.......... Simmering Burner..............----------------- --------- -------------------------- ------- ------------------------------- 5000 * * * Coffee Urn--Large, 18 in. Diameter--Single Drum.........................._............................... 5000 Coffee Urn--Small, 12 in. Diameter--Single Drum.;-- .................. ....................._......... 3000 Coffee Urn--Per Gallon of Rated Capacity.-------------- ----------------------- ---- --................ 500 Egg Boiler--Per Egg Compartment.................. ...............--............ .............................. ......... 2500 Steam Table or Serving Table--Per Square Foot of Top Surface..........._................. 400 Dish Warmer--Per Square Foot of Shelf.------------------------------------- .----------- ------- -------- 540 Cigar Lighter--Continuous Flame Type........ -- ------------ --.............: :......................... 2250 Curling Iron Heater............................ --................ ................ ...............--------------- -------------------Bunsen Type Burner--Large--Natural Gas------- ------- ------------------------.--------------------Bunsen Type Burner--Large--Artificial Gas---------- ------------------ ~---------------------------Bunsen Type Burner--Small--Natural Gas......................... .............. -............................... Bunsen Type Burner--Small--Artificial Gas..........................................-.............-.............. Welsbach Burner--Natural Gas-....... -_________ __________________ ____ ____ __________ Welsbach Burner--Artificial Gas................. ................ ............................... ......... - ---------- Fish-tail Burner--Natural Gas............................................ ................... ...... .......................... -- Fish-tail Burner--Artificial Gas.................................................................................... ............... 2250 * * \ * * * * Lighting Fixture Outlet--Large, 3 Mantle 480 C.P----------------- ---- --------- ---- ------------ 4500 Lighting Fixture Outlet--Small, 1 Mantle 160 C.P--....................--.......................... 2250 One Cubic Foot of Natural Gas Generates--------------------------------------- ------------------- ---- 900 One Cubic Foot of Artificial Gas Generates..--__________________ ---------------------- 540 One Cubic Foot of Producer Gas Generates-................. ------------------------ ------ --------- -- 135 10% 33% 50% 1000 6000 5000 * * *' * 5000 3000 500 2500 900 60 250 250 * * 0 *, 0 0 0 500 250 100 60 15 100% 100% 100% 10000 18000 10000 12000 10000 18000 250 100000 100 250 2500 10000 6000 1000 5000 1300 600 2500 2500 5000 3000 3000 1800 3000 1800 5000 3000 5000 2500 1000 600 150 _______ ________________________ Steam Heated Equipment ' Steam Heated Surface Not Polished--Per Square Foot of Surface.---------------------Steam Heated Surface Polished--Per Square Foot of Surface------------------------ ------- Insulated Surface. Per Square Foot............................... .................................... -...................... Bare Pipes. Not Polished Per Square Foot of Surface............... ........................................ Bare Pipes, Polished Per Square Foot of Surface.-..... --..................................... --.......- Insulated Pipes. Per Square Foot--------------------- ------------------------------------ -------------------Coffee Urn--Large, 18 in. Diameter--Single Drum------------------------------------------------Coffee Urn--Small, 12 in. Diameter--Single Drum--................ -....... -......................... Egg Boiler--Per Egg Compartment............. .--................. -.............-........ --.................~~ Steam Table--Per Square Foot of Top Surface....................... --................ ........................ 330 130 80 400 220 110 2000 1200 2500 300 0 330 0 130 0 80 0 400 0 220 0 no 2000 4000 1200 . 2400 2500 5000 800 1100 Miscellaneous Heat Liberated By Food per person, as in a Restaurant---------.------------------------------- 30 30 Heat Liberated from Hot Water used direct and on towels per hour--Barber Shops 100 200 60 300 Per cent sensible and latent heat depends upon use of equipment; dry heat, baking or boiling. CHAPTER 8. COOLING LOAD Heat Emission of Appliances Heat generating appliances which give off either sensible heat or both sensible and latent heat in an air conditioned enclosure may be divided into three general classes of equipment or devices: 1. Electrical appliances. 2. Gas appliances. 3. Steam heating appliances. In the first group may be found such devices as lights, motors, toasters, waffle irons, etc. The capacities of most electrical devices may be determined from the watt capacity indicated on their name plates. The Btu equivalent of heat generated per hour is determined by multi plying the watt capacity by 3.4 (one watthour is equivalent to 3.413 Btu). The capacities of electric motors are usually expressed in terms of horsepower instead of watts. If the motor efficiency is known, the watts input may be calculated from the formula: where p = 746 (kp) n P = motor'input, watts. hp = motor load, horsepower, n = motor efficiency (expressed as a decimal). '' When the motor efficiency is not known the heat equivalent of electrical input can be approximately determined by applying data given in Table 9. Table 9. Heat Generated by Motors Nameplate Rating Horsepower Hto H H to 3 3 to 20 Heat Gain in Btu per Hour per Horsepower Connected Load in Same Room Connected Load Outride of Room 4250 3700 2950 1700 1150 400 In the second group belong such appliances as coffee urns, gas ranges, steam tables, broilers, hot plates, etc. For heat generating capacities of such appliances refer to Table 10. . Considerable judgment must be exercised in the use of data given in Table 10. Consideration must be given to time of day when appliances are used and the heat they contribute at time of peak load. Only those appliances in use at the time of the peak load need be considered. Con sideration must also be given to the way appliances are installed, whether products of combustion are vented to a flue, whether they escape into the space to be conditioned, or whether appliances are hooded allowing part of the heat to escape through a stack. There are no generally accepted data available on the effects of venting and shielding heating appliances but it is believed that when they are properly hooded with a positive fan exhaust system through the hood that 50 per cent of the heat will be HEATING VENTILATING AIR CONDITIONING GUIDE 1940 carried away and 50 per cent dissipated in the space to be conditioned. Where latent as well as sensible heat is given off, it is usually safe to assume that all latent heat will be removed by a properly designed and operated vent or hood. GENERAL From the foregoing discussion it is obvious that the determination of the maximum cooling load is rather complicated by reason of the variable nature of contributing load components. Application of the foregoing data in determining cooling load require ments is illustrated in Example 1. . Example 1. Determine cooling load requirements for a clothing store illustrated in Fig. 3 and located in Pittsburgh, Pa., Latitude 40 deg. This is a one-story building located on a corner and it faces south and west. Assume building on east and north sides conditioned. Wall construction, 8 in. hollow tile, 4 in. brick veneer, plaster on walls, U -- 0.33 (Table 4, Chapter 5, No. 38 B). Roof construction, 2 in. concrete, K in. rigid insulation, metal lath and plaster ceiling, U = 0.26 (Table 11, Chapter 5, No. 2 J). . Floor, maple flooring on yellow pine, no ceiling below, U = 0.34 (Table 8, Chapter 5, No. ID). . Partition, wood lath and plaster on both sides of studding, TJ = 0.34 (Table 6, Chapter 5, No. 77 B). Show windows, provided with awnings and thin panel partition at rear. Front doors, 2 ft 6 in. x 7 ft (glass paneled), V ~ 1.13 (Table 13 A, Chapter 5). Side doors, 3 ft x 7 ft (solid, IK in. thick), U = 0.51 (Table 13 B, Chapter 5). Occupancy, 10 clerks, 40 patrons. , Lights, 4200 w. Outside design conditions, dry-bulb 95 F; wet-bulb 75 F. Inside design conditions, dry-bulb 80 F; wet-bulb 67 F. . ' Basement temperature, 85 F. Store room temperature, 88 F. CHAPTER 8. COOLING LOAD Solution. The normal heat transmission through various surfaces shown in load calculations are determined by application of Formula 1. It is quite obvious from the shape and exposure of.this store that the maximum sun load will exist on the west wall. Since the west wall has a large glass area with a negligible time lag, the peak load may be expected at 4.-00 p.m. at which time, from Table 4, / = 211. As explained in the text, the normal transmission load through these windows is omitted because it is small in comparison with the sun load./ I for the south side at 4:00 p.m. is 8. Because of the small amount of solar radiation transmitted through the south glass, it can be neglected and the total heat gain taken as that due to normal transmission. Assuming time lag in roof and walls to be 2 hr, the corresponding values for I for south and west walls and roof will be those shown in Table 4 (or 2:00 p.m. They are respectively 77, 143 and 258. A time lag of 1 hr was assumed for the west door amounting to / = 192. By substituting these values in Equations 2 and 3 the solar heat load is determined. To determine the heat gain from the outside air it is necessary first to determine the volume of the outside air to be introduced. Since the show windows are sealed so as not' to permit infiltration and since there are only three doors in this store through which infiltration can take place, it is obvious that infiltration of air will be a negligible quan tity. The volume of the store is 21,600 cu ft. Good .practice indicates that in a store of this character there should be a minimum of from 1 to IK outside air changes per hour. On a basis of IK air changes the volume of outside air to be introduced would be 32,400 cfh. The minimum ventilation requirements as given in the Code of Minimum Require ments for Comfort Air Conditioning* are 10 cfm per person. On this basis the ventilation requirements would be 30,000 cfh. Since this will produce approximately IK outside air changes per hour, 30,000 cfh will be considered in this application. To determine load imposed by occupants it will be found from Table 4, Chapter 3 that the average person standing at rest will dissipate 225 Btu sensible heat and 206 Btu latent heat per hour. Normal Transmission Load: Surface S Glass S Wall W Wall W Door Roof Floor N Partition Total Doqnsionb 2(2 ft 6 in. x7ft) + 2(10 ft x 6 ft) (30 ft x 12 ft)-155 (60 ft x 12 ft)-321 3 ft x 7 ft 60 ft x 30 ft 26 ft x $4 ft . . 30 ft x 12 ft . Aht.^ SQ FT 155 205 399 21 1800 1404 360 U 1.13 0.33 0.33 0.51 0.26 0.34 0.34 Tbhp. Dot.* Deo F Btu res Hour 15 15 1,015 15 1,975 15 15 7,020 5 2^387 8 979 16.164 Sun Load: lO 'xF 154 10'x6' Outside Air Heat Gain: Sensible heat, Hs = 0.24 X 60 do Q (to -- /) (Formula 4). Q = 50 X 10 = 500 cfm. C<ieof Minimum Requirements for Comfort Air Conditioning (A.S.H.V.E. Transactions. VoI 44. lyais. p. 27). Reprints of this code are available at $.10 a copy. 155 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Density of air at 95 F dry-bulb and 75 F wet-bulb for a barometric pressure of 29.92 in. is 0.07105 lb per cubic foot (Table 4, Chapter .1). ... Dew-point of outdoor air is 66 F (psychrometric chart). .' Partial pressure of vapor is 0.64378 in. Hg. (Pressure of saturated vapor at 66 F, Table 6, Chapter 1). . w-0622 (irb) -0622 Uw^OMSfs) = '0137 lb water vapor per pound dry air (Formula 5 a, Chapter 1). --------- * -- = 0.986 lb dry air per pound outside air. 1 + 0.0137 . - do = 0.07105 X 0.986 = 0.0699 lb dry air per cubic foot outside air. , Ha = 60 X 500 X 0.0699 X 0.24 (95-80) = 7549 Btu per hour. . Toted heat, H = 60 do Q {.ho -- h) (Formula 5). ho ~ 38.46 Btu per pound dry air at 75 F wet-bulb (Table 6, Chapter 1). h = 31.51 Btu per pound dry air at 67 F wet-bulb (Table 6, Chapter 1). H = 60 X 0.0699 X 500 (38.46 -- 31.51) = 14,574 Btu per hour. Latent heat gain from outside air = 14,574 -- 7549 = 7025 Btu per hour. People Heat Gain: 50 X 225 = 11,250 Btu per hour, sensible heat. 50 X 206 -- 10,300 Btu per hour, latent heat. . Light Heat Gain: 4200. X 3.413 = 14,335 Btu per hour. Summary: Component op Load ' Btu fkb Houb ' Sensible 16.164 47.946 . 7,549: 11.250 14,335 97.244 Latent 7.025 i 10,300 17.325 Total Load: - 97,244 + 17,325 = 114,569 Btu per hour., 156 Chapter 9 COMBUSTION AND FUELS Principles of Combustion, Classification of Coals, Firing Methods for Coals, Firing Methods for Coke, Dustless Treat ment of Coal, Classification of Oils, Combustion of Oil, Classi fication of Gas, Combustion of Gas. THE data given in the first part of this chapter are of general appli cation to the various fuels used in domestic heating which are coal, coke, oil and gas. The choice of fuel is a question of dependability, cleanliness, fuel availability, economy, operating requirements and control. FUNDAMENTAL PRINCIPLES OF COMBUSTION Combustion may be defined as the chemical combination of a substance with oxygen with a resultant evolution of heat. The rate of combustion depends partly upon the specific rate of reaction of the combustible substance with oxygen and partly upon the rate at which oxygen is supplied and the surrounding conditions as they define the temperature. Complete combustion is obtained when all of the combustible elements in the fuel are oxidized with all of the oxygen with which they can combine. All of the oxygen supplied may not be utilized. Perfect combustion is defined as the result of supplying the required amount of oxygen for combination with all of the combustible elements of the fuel and utilizing all of the oxygen so supplied. ! The oxygen required for the process of combustion is obtained from air which is a mechanical mixture of oxygen, nitrogen and small amounts of carbon dioxide, water vapor and inert gases. These inert gases are generally included with the nitrogen, and for engineering purposes the values given herewith may be used. . Oxygen, Ot.......................................................... Nitrogen, Nt................. ................ Bt Volume Per Cent 20.9 79.1 Bt Weight Ppa Cent 23.15 76.85 The combination of oxygen with the combustible elements and com pounds of, a fuel is in accordance with fixed laws. In the case of perfect combustion the reactions and resultant combinations are shown in Table 1. The most important condition governing the process of combustion is temperature. It is necessary to bring a combustible substance to its 157 a b l e 1 . G e n e r a l D a t a o f C o m b u s t ib l e E l e m e n t s a n d C o m p o u n d sT F ro m In te rn a tio n a l C ritic a l Tables, 1927.. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 158 CHAPTER 9. COMBUSTION AND FUELS ignition temperature before it will unite in chemical combination with oxygen to produce combustion. The ignition temperatures for several of the combustible constituents of fuels are presented in Table 1. HEAT OF COMBUSTION As previously stated, the process of combustion results in the evolution of heat. The heat of combustion, or calorific value, of a fuel is the amount of heat generated by the complete combustion of a unit of the fuel and is constant for a given combination of combustible elements and compounds. The heat of combustion of the several fuel elements and compounds in their pure state is given in Table 1. The reaction of the carbon in the fuel with oxygen may result in the formation of carbon monoxide or carbon .dioxide. In burning to carbon monoxide, the carbon is not completely oxidized and, as shown by the data, the heat produced is considerably less than if it were completely oxidized. This fact is of greatest importance in considering the efficiency of combustion. The calorific value of a fuel is determined by direct measurement of the heat evolved during combustion in a calorimeter. As the calorific value, on a moisture and ash free basis, of coal from a given district or mine remains substantially constant the calculation of the calorific value of a particular lot of coal can be made if the lot is analyzed for moisture and ash. From a known reliable calorific value for coal from the same mine or district the calorific value on a "moisture and ash free" basis, often called the H value, is calculated from Formula (1). Calorific value, moisture and ash free 100 X Calorific value (as received) 100 -- (Moisture 4- Ash) U) If a dry or moisture free analysis is used it is necessary to correct for ash only to reduce to moisture and ash free basis. From the value ob tained by Formula (1) the calorific value for the sample under consider ation can be calculated as follows: ' Calorific value (moisture and ash free) X [100 -- (Moisture + Ash)] Calorific value = 100 (2) In the above formulae moisture and ash are expressed in per cent. The H values for Illinois coals are published1 and it is to be expected that more data on H values for other coals will be available in the future. As practically all fuels contain hydrogen they produce a certain amount of water vapor as one of the products of combustion. The amount of water vapor produced increases as the hydrogen content of the fuel increases. When the calorific value of a fuel is determined in a calori meter the water vapor is condensed and the latent heat of vaporization that is given up during the condensation is reported as a portion of the heat value of the fuel. The heat value so determined is termed the gross or higher heat value and this is what is ordinarily meant when the heat value of a fuel is specified. In burning the fuel, however, the products of lState Geological Survey Bulletin, No. 62. Classification and Selection of Illinois Coals. 159 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 combustion are not cooled to the dew-point and the higher calorific value cannot be obtained. FLAME The appearance of the flame or products of combustion may serve as an1 approximate measure of the temperatures developed in the combustion process. The luminosity of a flame is caused by the heating to incan descence of unconsumed particles of combustible matter in the gases and the higher the temperature of these particles the whiter the flame.- Table 2 gives some approximate flame temperature data. AIR AND COMBUSTION The weight of air required for the perfect combustion of a pound of fuel may be determined by use of the ultimate analysis of the fuel as applied to Formulae 3 to 5. The various elements are expressed in percentages by weight. Table 2. Flame Temperature Data Appearance op Flame Red, visible in daylight........ ............................................. ,,............. Light red. _ ................................................................ ........ ........... Orange-red......................................................................................... Orange-yellow........................................... ....................................... Yellow-white.-_:................................................ ................ Temperature Deo F 975 1832 2012 2192 2372 2550 Solid and. Liquid Fuels: Pounds air required per pound fuel = 34.56 -Cg- + IlH + --0-\j + --S Gaseous Fuels: Pounds air required per pound fuel = 2.46 CO + 34.56 H, + 17.28 CH, + 13.29 C,H, + 14.81 CsH, + 16.13 CJ1, + 6.10 H,S - 4.32 Oj (3) (4) When the analysis is given on a volumetric basis the formula is'express ed as follows: Cubic feet air required per cubic foot gas = 2.39 (CO + Hi) + 9.56 CH, + 11.98 C,H, + 14.35 C,H, + 16.74 CiH, - 4.78 O, . (5) Formulae 6 and 7 may be used as approximate methods of determining the theoretical air requirement for'any fuel. . Pounds air required per pound fuel ,, ,,,, w Calorific value (Btu per pound) U./55 X -- iQOO (6) Cu.bi.c free.t air requi.red. per unit f,ue,l = -C--a--l-o--r-i-f-i-c---v--a--l-u-e---(-B---t-u---p--e-r---u--n--i-t)- (7) Approximate values for the theoretical air required for different fuels are given in Table 3. It is customary to make use of the analysis of the products of com bustion to determine the amount of flue gets produced and the actual 160 CHAPTER 9. COMBUSTION AND FUELS amount of air supplied for combustion. The analysis of flue gases has been well described in various publications of the Bureau of Mines and in the literature and the details of Orsat manipulation need not be considered in this discussion. (See Chapter 45.) The weight of dry flue gas per pound of fuel burned is used in com bustion loss calculations and may be determined by Formula 8. Pounds dry flue gas per pound fuel 11 CO,+ 8 0,+ 7 (CO + N,) ,, r 3 (CO, + CO) * (8) Values for CO,, Oi, CO and N, are percentages by volume from the flue gas analysis and C is the weight of carbon burned per pound of fuel corrected for carbon in the ash. , Table 3. Theoretical Air Requirements Solid Fuel Anthracite........................... Semi-bituminous coal-- Bituminous coal............... Lignite.................................. Coke--..........................-- Founds Air Pee Pound Fuel .. 9.6 11.2 10.3 6.2 11.2 Fuel Oil Pounds Air Peb Gallon Fuel 102.6 104.5 106.5 112.0 114.2 Gaseous Fuels Cubic Feet Am Per Cubic Foot Gas 10.0 4.4 4.4 2.1 5.2 EXCESS AIR Because the real measure of the efficiency of combustion is the relation existing between the amount of air theoretically required for perfect com bustion and the amount of air actually supplied a method of determining the latter factor is of value. Formula 9 will give reasonably accurate results, for most solid and liquid fuels, for determining the amount of air supplied per pound of fuel. Pounds dry air supplied per pound of fuel 3.036 N, (CO, + CO) X (9) Values for CO,, CO and N are percentages by volume from the flue gas analysis and C is the weight of carbon burned per pound of fuel corrected for carbon in the ash. . 161 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The relationship of the air supplied, as determined from the previous formula, to the theoretical air required indicates the per cent of excess air supplied. A formula that may be used to determine directly the per cent of excess air is expressed : 100 (o, . Per cent excess air = ------------------------ y------------rn\ N, X 0.264 - ( 0, - (10) . In this formula the symbols represent volumetric percentages of the flue gas constituents as determined by analysis. The amount of excess air in its relation to the percentage of COt is shown by the curves in Fig, 1 for several fuels. These are approximate values. It should be noted that in hand-fired furnaces with long periods between firings the combustion goes through a cycle in each period and the quantity of excess air present varies. CHAPTER 9. COMBUSTION AND FUELS the coke is COt and under certain conditions some CO may arise from the bed. The combustion of the volatile matter and the CO may amount to the liberation of from 40 to 60 per cent of the heat in the fuel in the combustion space over the fuel bed. The air that passes through the fuel bed is called primary air and the air that is admitted over the fuel bed in order to burn the volatile matter and CO is called secondary air. Table 4. Maximum COt Values . Fuel oif ...... ................................................................................................ ....... Per Cent COt 21.0 20.2 1S.2 15.5 11.5 9.25 This process of combustion is illustrated in Fig. 22. The free oxygen of the air passes through the grate and the ash above it and bums the carbon in the lower three or four inches of the fuel bed forming carbon dioxide. This layer noted as the oxidizing zone is indicated by the symbols CO% and Ot- Some of the carbon dioxide of the oxidizing zone is reduced to carbon monoxide in the upper layer of the fuel bed noted as the reducing zone and indicated by the symbols COt and CO. The gases leaving the fuel Fig. 1. Relation Between CO and Excess Air in Gases of Combustion Due to the different carbon-hydrogen ratios of the different fuels the maximum COt attainable varies. Representative values for perfect com bustion of several fuels are given in Table 4. In considering the factor of excess air it should be noted that a deficien cy of air supply will result in combustible products passing to the stack unburned. An excess of air absorbs heat from the products of combustion and results in a greater loss of sensible heat to the stack. An excess of air is usually required, however, to eliminate combustible losses occasioned by poor mixing of the fuel and air. It is considered good practice, under usual operating conditions, to supply from 25 to 50 per cent excess air, dependent upon the fuel utilized. SECONDARY AIR When a solid fuel is hand-fired in a furnace the volatile matter in the fuel distills off leaving coke on the grate. The product of combustion of 162 Fig. 2. Combustion of Fuel in a Hand-Fired Furnace bed are mainly carbon monoxide, carbon dioxide, nitrogen and very little free oxygen. Free oxygen is admitted through the firing door to bum carbon monoxide and the volatile combustible distilled from the freshly fired fuel. The division of the total into primary and secondary air necessary to produce the same rate of burning and the same excess air depends on a number of factors which include size of fuel, depth of fuel bed, and size of fire-pot. The ratio of' the secondary to the primary air increases with* *From Bureau of Mines Technical Paper No. 80. 163 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 decrease in the size of the fuel pieces, with, increase in the depth of the fuel bed, and with increase in the area of the fire-pot; the ratio also increases with increase in rate of burning. . Size of the fuel is a very important factor in fixing the quantity of secondary air required for non-caking coals. With caking coals it is not so important because small pieces fuse together and form large lumps. Fortunately a smaller size fuel gives more resistance to air flow through the fuel bed and thus automatically causes a larger draft above the fuel bed, which draws in more secondary air through the same slot openings. In spite of this, a small size fuel requires a larger opening of the door slots; for a certain size for each fuel no slot opening is required, and for larger sizes too much excess air gets through the fuel bed. Fig. 3. Relative Amount of Fire Door Slot Opening Required in a Given Furnace to Give Equally Good Combustion for High Temperature Coke of Various Sizes When Burned at Various Rates It is impossible to establish a single rule for the correct slot opening for all types and sizes of fuels and for all rates of burning. Furthermore, the effect of slot opening is dependent on whether the ashpit damper is open or closed. It is better to have too much than too little secondary air; the opening is too small if there is a puff of flame when the firing door is opened. The relationship of the slot opening, for a domestic furnace, to .the size of coke and the rate of burning is shown in Fig. 33. These openings are with the ashpit damper wide open, and would be less if the available draft permits of its being partly closed. The same openings are satisfactory for anthracite. Bituminous coals require a large amount of secondary air during the period subsequent to a firing in order to consume the gases and to reduce the smoke. The smoke produced is a good indicator, and that opening is* *Froni Bureau of Mines Report of Investigations, No. 2980. 164 CHAPTER 9. COMBUSTION AND FUELS best which reduces the smoke to a minimum. Too much secondary air will cool the gases below the ignition point, and prove harmful instead of beneficial. The following suggestions will be helpful: ' 1. In cold weather, with high combustion rates, the secondary air damper should be half open all the time. 2. In very mild weather, with a very low combustion rate, the secondary air damper should be closed all the time. 3. For temperatures between very mild and very cold, the secondary air damper should be in an intermediate position. 4. For ordinary house operation, secondary air is needed after each firing for about one hour. ' In the field of domestic heating the use of secondary air in the com bustion of oil is generally restricted to the larger semi-commercial types of oil burners used in large heating boilers. This factor is discussed in Chapter 11, Automatic Fuel Burning Equipment. The air that is supplied around the flame in a domestic heating gas burner is considered as secondary air. As it is drawn into the appliance by natural draft action, the need for proper draft control is evident. Draft Requirements The draft required to effect a given rate of burning the fuel as measured at the smokehood is dependent on the following factors: 1. Kind and size of fuel. 2. Combustion rate per square foot of grate area per hour. 3. Thickness of fuel bed. . 4. Type and amount of ash and clinker accumulation. 5. Amount of excess air present in the gases. . 6. Resistance offered by the boiler passes to the flow of the gases. 7. Accumulation of soot in the passes. Insufficient draft will necessitate additional manipulation of the fuel bed and more frequent cleanings to keep its resistance down. Insufficient draft also restricts the control by adjustment of the dampers. The quantity of excess air present has a marked affect on the draft required to produce a given rate of burning. If the excess is caused by holes in the fuel bed or an extremely thin fuel bed it is often possible to produce a higher rate of burning by increasing the thickness of the bed. The thickness of the fuel bed should not, however, be increased too much because the increased draft resistance will reduce the rate of primary air supply and the rate of burning. DRAFT REGULATION Because of the varying heating load demands present in most instal lations it is necessary to vary the rate of fuel burning. The maintenance of the proper air supply for the various rates of burning is accomplished by regulation of the drafts. Correct and incorrect methods of draft regulation are shown in Fig. 4. The air enters through the ashpit, firing door and by leaks in the setting, whereas the gases leave only through the uptake. . By throttling the gases with the damper in the uptake all the air entering by each of the three intakes is reduced in the same proportion. 165 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 If the ashpit door is closed the air admitted through the ashpit is reduced and increased through the other two intake openings. Methods of control of draft conditions when burning oil or gas are , noted in Chapter 11, Automatic Fuel Burning Equipment. CLASSIFICATION OF COALS . The complex composition of coal makes it difficult to classify it into clear-cut types. Its chemical composition is some indication but coals having the same chemical analysis may have distinctly different burning . characteristics. Users are mainly interested in the; available heat per . Fig. 4. Correct and Incorrect Methods of Draft Regulation in a Hand-Fired Furnace pound of coal, in the handling and storing properties, and in the burning characteristics. A description of the relationship between the qualities of coals and these characteristics requires considerable space; a treatment applicable to heating boilers is given in Bureau of Mines Bulletin No. 276. The classification of coals by rank involves several of the items indicated in a proximate analysis of the coal. This analysis determines the content of volatile matter, fixed carbon, ash and moisture. The calorific value and sulphur content are often reported with the proximate analysis. Volatile matter is the loss of weight when the coal sample is heated to 1732 F for 7 min. Fixed carbon is the difference from 100 per cent of the sum of other losses, not including sulphur. Ash is the incombustible impurity in the coal and has no heating value. Moisture is the inherent and ex traneous water in the fuel. Other important qualities of coals are the screen sizes, ash softening temperature, friability, caking tendency, and the qualities of the volatile matter. In considering these factors the following points are of interest. . The volatile products given off by coals when, they are heated differ materially in the ratios by weight of the gases to the oils and tars. . No heavy oils or tars are given off by anthracite, and very small quantities are given off by semi-anthracite. As the volatile matter in the coal increases to as much as 40 per cent of ash and moisture-free coal, in creasing amounts of oils and tars are released. For coals of higher volatile content, the relative quantity of oils and tars decreases, so it 166 . --. ______ , CHAPTER 9. COMBUSTION AND FUELS is low in the sub-bituminous coals and in lignite. The percentage of ash and its fusion temperature do not indicate how the ash is distributed or how much of it is less fusible lumps of slate of shale. ' A classification of coals is given in Table 5, and a brief description of the kinds of fuels is given in the following paragraphs, but it should be recognized that there are no distinct lines of demarcation between the kinds, and that they graduate into each other. Anthracite is a clean, dense, hard coal which creates very little dust in handling. It is comparatively hard to ignite but it burns freely when well started. It is non-caking, it burns uniformly and smokelessly with a short flame, and it requires little attention to the fuel bed between firings. It is capable of giving a high efficiency in the common types of hand-fired furnaces. A tabulation of the quality of the various anthracite sizes will be found in Bureau of Mines Report of Investigations No. 3283. Semi-anthracite has a higher volatile content than anthracite, it is not as hard and ignites somewhat more easily; otherwise its properties are similar to those of anthracite. Table 5. Classification of Coals by Rankq Legend: F.C. = Fixed Carbon. V.M. = Volatile Matter. Btu = British thermal units. Class Geoop Limits of Fixed Carbon ob Btu Mwbhal-Matteb-Fbeb Basis Requisite Physical Properties I. Anthracite_____ 1. Meta-anthracite____ _________ 2. Anthracite 3. Semi-anthrurite Dry F.C., 98 per cent or more (Dry V.M., 2 per cent or less) Dry F.C., 92 per cent or more and less than 98 per cent (Dry V.M., 8 per cent or las and more than 2 per cent] Dry F.C., 86 per Cent or more and less than 92 per cent (Dry V.M., 14 per cent or less and more than 8 per cent) Non-agglomerating6 U. Bituminous*--__ 1. Low volatile bituminous ___ Dry F.C., 78 per cent or more and lees than 86 per cent (Dry V.M, 22 per cent or less and more than 14 per cent) 2. Medium volatile bituminous coal Dry F.C., 69 per cent or more and less than 78 per cent (Dry V.M., 31 per cent or less and more than 22 Der cent) 3. High volatile A bituminous Dnr F.C., less than 69 per oent (Dry V.M., more than 31 pa cent); and moist* Btu. 14,000* or more 4. High volatile B bituminous <***1 Moist* Btu. 13,000 or more and Iww than 14.000* 5. High volatile C bituminous paI Moist Btu, 11,000 or more and less than 13.000* HSther agglomerating6 or non-weathering/ I1L 8ub-bituminous2. Brown ensd Moist Btu, 11,000 or more and lww than 13,000* Moist Btu, 9500 or more and lees Both weathering and than 11,000* non-agglomerating6 Moist Btu, 8300 or more and less than 9500* Moist Btu lww than 8300 Moist Btu less than 8300 rank. AltS fh. ", * *"** car"n or Btu of the high-volatile bituminous and sub-bituminous i s i&S"5 JS "`Bet contain less than 48 per cent dry. mineral-matter-free fixed carbon or have more than 15,500 moist, mineral-matter-free Btu. UdVC *If agglomerating, classify in low-volatile group of the bituminous class, surface of thecoal'18 l Ca' containing its natural bed moisture but not including visible water on the 'It is recognised that there may be non-caking varieties in each group of the bituminous class, according ofB?u"rb0n " "" ^ minal-ma"cr-f* basis "Ball be classified awk!r!!fTM,fre variet*es of coal in the High-volatile C bituminous coal group, namely. Variety 1 and <rmn-weaUieringn"Wathenng' Vanety 2- a8glomerating and weathering; Variety 3. non-agglomerating . Philadelphia. *r0m A-S T-M- Standards. 1937. Supplement, p. 145. American Society for Testing Materials. 167 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Semi-bituminous coal is soft and friable, and fines and dust are created by handling it. It ignites somewhat slowly and burns with a medium length of flame. Us caking pro perties increase as the volatile matter increases, but the coke formed is relatively weak. Having only half the volatile matter content of the more abundant bituminous coals it can be burned with less production of smoke, and it is sometimes called smokeless coal. The term bituminous coal covers a large range of coals and includes many .types having distinctly different composition, properties, and burning characteristics. The coals range from the high-grade bituminous coals of the East to the poorer coals of the West. Their caking properties range from coals which completely melt, to those from which the volatiles and tars are distilled without change of form, so that they are classed as non caking or free-burning. Most bituminous coals are strong and non-friable enough to permit of the screened sizes being delivered free from fines. In general, they ignite easily and burn freely; the length of flame varies with different coals, but it is long. Much smoke and soot are possible especially at low rates of burning. Sub-bituminous coals occur in the western states; they are high in moisture when mined and tend to break up as they dry or when exposed to the weather; they are liable to ignite spontaneously when piled or stored. They ignite easily and quickly and have a medium length flame, are non-caking and free-burning; the lumps tend to break into small pieces if poked; very little smoke and soot are formed. Lignite is of. woody structure, very high in moisture as mined, and of low heating value; it is clean to handle. It has a greater tendency than the sub-bituminous coals to disintegrate as it dries, and it also is more liable to spontaneous ignition. Freshly mined lignite, because of its high moisture, ignites slowly. It is non-caking. The char left after the moisture and volatile matter are driven off burns very easily, like charcoal. The lumps tend to break up in the fuel bed and pieces of char falling into the ashpit continue to burn. Very little smoke or soot is formed. .. It is often desirable to learn about the properties of a coal, such as the various items noted in the discussion of proximate analyses. As a guide for the consumer as to the expected characteristics of coals several commercial publications are available and numerous reports of the Bureau of Mines discuss the coals produced in individual state areas. CLASSIFICATION OF COKES Coke is produced by the distillation of the volatile matter from coal. The type of coke depends on the coal or mixture of coals used, the temperatures and time of distil lation and, to some extent, on the type of retort or oven; coke is also produced as a residue from the destructive distillation of oil. High-temperature cokes. Coke as usually available is of the high-temperature type, and contains between 1 and 2 per cent volatile matter. High-temperature cokes are sub divided into beekive coke of which comparatively little is now sold for domestic use, by product coke, which covers the greater part of the coke sold, and gas-house coke. The differences among these three cokes are relatively small; their denseness and hardness decrease and friability increases in the order named. In general, the lighter and more friable cokes ignite and burn the more easily. Low-temperature cokes are produced at low coking temperatures! and only a portion of the volatile matter is distilled off. Cokes as made by various processes under develop ment have contained from 10 to 15 per cent volatile matter. In general, these cokes ignite and burn more readily than high-temperature cokes. The properties of various low-temperature cokes may differ more than those of the various high-temperature cokes because of the differences in the quantities of volatile matter and because some may be light and others briquetted. Petroleum cokes, which are obtained by coking the residue left from the distillation of petroleum, vary in the amount of volatile matter they contain, but all have the common property of a very low ash content, which necessitates the use of refractory pieces to protect the grates from being burned. FIRING METHODS FOR ANTHRACITE4 An anthracite fire should never be poked, as this serves to bring ash to the surface of the fuel bed where it melts into clinker. .* *s reports published by Anikracile Industries Laboratory. Primus; Delaware County, Pennsylvania. CHAPTER 9. COMBUSTION AND EUELS Egg size is suitable for large firepots (grates 24 in. and over) if the fuel can be fired at least 16 in. deep. The air spaces between the pieces of coal are large, and for best results this coal should be fired deeply. Stove size coal is the proper size of anthracite for many boilers and furnaces used for heating buildings. It burns well on grates at least 16 in: in diameter and 12 in. deep. The only instructions needed for burning this type of fuel are that the grate should be shaken daily, the fire should never be poked or disturbed, and the fuel should be fired deeply and uniformly. . Chestnut size coal is in demand for fire-pots up to 20 in. in diameter, with a depth of from 10 to 15 in. Pea size coal is often an economical fuel to burn. It is relatively low in price. When fired carefully, pea coal can be burned on standard grates. It is well to have a small amount of a larger fuel on hand when building new fires, or when filling holes in the fuel bed. Care should be taken to shake the grates only until the first bright coals begin to fall through the grates. The fuel bed, after a new fire has been built, should be increased in thickness by the addition of small charges until it is at least level with the sill of the fire-door. This keeps a bed of ignited coal in readiness against the time when a sudden demand for heat shall be made on the heater. A very satisfactory method of firing pea coal consists of drawing the red coals toward the front end and piling fresh fuel toward the back of the fire-box. Pea size coal requires a strong draft and therefore the best results generally will be obtained by keeping the choke damper open and regu lating solely by means of the cold air check and the air inlet damper. As a precaution against clinker, it is well to adjust the air inlet damper so that it can never be completely closed under any operating conditions. Buckwheat size coal for best results requires more attention than pea size coal, and in addition the smaller size of the fuel makes it more difficult to burn on ordinary grates. Greater care must be taken in shaking the grates than with pea coal on account of the danger of the fuel falling through the grate. In house heating furnaces the coal should be fired lightly and more frequently than pea coal. When banking a buckwheat coal fire it is advisable after coaling to expose a small spot of hot fire by putting a poker down through the bed of fresh coal. This will serve to ignite the gas that will be distilled from the fresh coal and prevent an explosion of gas within the fire-pot, which in some cases depending upon the thickness of the bed of fresh coal is severe enough to blow open the doors and dampers of the furnace: A good draft is required and conse quently the fire is best controlled by the air-inlet damper only. Where frequent attention can be given and care exercised in manipulation of the grates this fuel can be burned satisfactorily without the aid of any special equipment. . In general it will be found more satisfactory with buckwheat coal to maintain a uniform heat output and consequently to keep the system warm all the time, rather than to allow the system to cool off at times and then to attempt to bum the fuel at a high rate while warming up. A uni form low fire will minimize the clinker formation and keep the clinker in an, 169 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 6. Anthracite Standards Classification Coal Size, Inches Through Z-pi Through 2-K 6 Through 1-54 Through 1M6 Through V\ 6 Over 2-J4e Over 1-54 Over ^546 Over Over 5^6 easily broken up condition so that it readily can be shaken through the grate. Forced draft and small mesh grates are frequently used for burning buckwheat anthracite. For best results and a higher degree of con venience, domestic stokers are used. No. 2 buckwheat anthracite, or rice size, is used only in domestic stokers. No. 3 buckwheat anthracite, or barley, has no application in domestic heating. The Anthracite Institute Standards of sizing are shown in Table 6 taken from Anthracite Industries Manual, Report No. 2403. FIRING METHODS FOR BITUMINOUS COAL Bituminous coal should never be fired over the entire fuel bed at one time. A portion of the glowing fuel should always be left exposed to ignite the gases leaving the fresh charge. Air should be admitted over the fire through a special secondary air device, or through a slide in the fire-door or by opening the fire-door slightly. If the quantity of air admitted is too great the gases will be cooled below the ignition temperature and will fail to burn. The fireman can judge the quantity of air to admit by noting when the air supplied is just sufficient to make the gases burn rapidly and smokelessly above the fuel bed. The red fuel in the fire-box, before firing, excepting only a shallow layer of coke on the grate, should be pushed to one side or forward or back ward to form a hollow in which to throw the fresh fuel; Some manu facturers recommend that all red fuel be pushed to the rear of the fire-box and that the fresh fuel be fired directly on the grate and allowed to ignite from the top. The object of this is to reduce the early rapid distillation .of gases and to reduce the quantity of secondary air required for smoke less combustion. It is well to have the bright fuel in the fire-box so placed that the gases from the freshly fired fuel, mixed with the air over the fuel bed, pass over the bed of bright fuel on the way to the flues. The bed of bright fuel then supplies the heat to raise the mixture of air and gas to the ignition temperature, thereby causing the gaseous matter to burn and preventing the formation of smoke. The importance of firing bituminous coal in small quantities at short intervals is discussed in the U. S. Bureau of Mines Technical Paper, No. 80. Better combustion is obtained by this method in that the fuel supply is maintained more nearly proportional to the air supply. t70 CHAPTER 9. COMBUSTION AND FUELS This is demonstrated in Fig. 5 where diagram A shows the air supply and the distillation of the volatile combustible when the firings are 5 min apart; and diagram B indicates the same relationships when the firings are 15 min apart. In both cases the amount of coal fired per hour and the weight of volatile combustible distilled from the coal are the same. This weight of volatile conbustible is represented by the shaded area under the saw-tooth curve. The horizontal dotted lines represent the constant air supply sufficient to burn the volatile matter represented by the shaded areas under each line. The shaded areas above each horizontal line represent for each air supply the loss from incomplete combustion of the volatile matter. The clear area under each horizontal line represents the loss from excessive air. As the air supply increases the loss from incom- Fig. 5. Relation of Rate of Distillation of Volatile Matter and Necessary Air Supply .. . plete combustion decreases but the loss from excessive air becomes larger. : The sum of the two losses is the least when the air supply is introduced as noted by the average line. It is evident that the sum of the losses fbr the average air supply is much larger in diagram B than in A which would indicate that small and frequent firings are better than large firings at long intervals. If the coal is of the caking kind the fresh charge will fuse into one solid mass which can be broken up with the stoking bar and leveled from 20 min to one hour after firing, depending on the temperature of the fire-box. Care should be exercised when stoking not to bring the bar up to the surface.of the fuel as this will tend to bring ash into the high temperature zone at the top of the fire, where it will melt and form clinker;.. The stoking bar should be kept as near the grate as possible and should be 171 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 raised only enough to break up the fuel. With fuels requiring stoking it may not be necessary to shake the grates, as the ash is usually dislodged duIritngisstaockkinnogw. ledged that it may be difficult to apply the outlined methods to domestic heating boilers of small size, especially when frequent attendance is impractical. The adherence to these methods insofar as practical, however, will result in better combustion. The output obtained from any heater with bituminous coal will usually exceed that obtainable with anthracite, since bituminous coal bums more rapidly than anthracite and with less draft. Bituminous coal, however, will require frequent attention to the fuel bed, because it burns unevenly, even though the fuel bed may be level, forming holes in the fire which admit too much air, chilling the gases over the fuel bed and reducing the available draft. FIRING METHODS FOR SEMI-BITUMINOUS COAL The Pocahontas Operators Association recommends the central cone method of firing, in which the coal is heaped on to the center of the bed forming a cone the top of which should be level with the middle of the firing door. This allows the larger lumps to fall to the sides, and the fines to remain in the center and be coked. The poking should be limited to breaking down the coke without stirring, and to gently rocking the grates. It is recommended that the slides in the firing door be kept closed, as the thinner fuel bed around the sides allows enough air to get through. FIRING METHODS FOR COKE Coke ignites less readily than bituminous coal and more readily than anthracite and burns rapidly with little draft. In order to control the air admitted to the fuel it is very important that all openings or leaks into the ashpit be closed tightly. A coke fire responds rapidly to the opening of the dampers. This is an advantage in warming up the system, but it also makes it necessary to watch the dampers more closely in order to prevent the fire from burning too rapidly. In order to obtain the same interval of attention as with other fuels a deep fuel bed always should be maintained when burning coke. The grates should be shaken only slightly in mild weather and should be shaken only until the first red particles drop from the grates in cold weather. The best size of coke for general use, for small firepots where the fuel depth is not over 20 in., is that which passes over a 1 in. screen and through a 1J4 in. screen. For large firepots where the fuel can be fired over 20 in. deep, coke which passes over a 1 in. screen and through a 3 in. screen can be used, but a coke of uniform size is always more satisfactory. Large sizes of coke should be either mixed with fine sizes or broken up before using. PULVERIZED COAL Although several pulverized coal burning units for domestic heating plant firing have been developed, none has attained extended use. Two general methods of adaptation have been employed, one where the coal is pulverized by the unit at the furnace and one where the coal is delivered to the home in pulverized form. 172 . CHAPTER 9. COMBUSTION AND FUELS FURNACE VOLUME The principal requirements for a hand-fired,furnace are that it shall have enough grate area and correctly proportioned combustion space. The amount of grate area required is dependent upon the desired combustion rate. ,. The furnace volume is influenced by the kind of coal used. Bituminous coals, on account of their long-flaming characteristic, require more space in which to burn the gases of combustion completely than do the coals low in volatile matter.. For burning high volatile coals provision should be made for mixing the combustible gases thoroughly so that combustion is complete before the gases come in contact with the relatively cool . heating surfaces. An abrupt change in the direction of flow tends to mix the gases of combustion more thoroughly. Anthracite requires practically no combustion space. DUSTLESS TREATMENT OF COAL The practice of treating the more friable coals to allay the dust they create is increasing. The coal is sprayed with petroleum products, par ticularly the lighter oils, a solution of calcium chloride or a mixture of calcium and magnesium chlorides. The latter salts are very hygroscopic and their moisture under normal atmospheric conditions keeps the surface of the coal damp, thus reducing the dust during delivery in the cellar, and obviating the necessity of sprinkling the coal in the bin. The coal is usually treated at the mine, but sometimes by. the local distributor just before delivery. The salt solutions are sprayed" under high pressure, using from 2 to 4 gal or from 5 to 10 lb of the salt per ton of coal, depending on its friability and size. Oil for the dustless treatment of coal is also applied under high pressure, in concentrations of 1 to 8 qt per ton of coal, depending upon the characteristics of the coal and oil. CLASSIFICATION OF OILS The Commercial Standard Specifications for Fuel Oils (CS 12-38) of the V. S. Department of Commerce are given in Table 7. These speci fications conform with American Society for Testing Materials Tentative Specifications for Fuel Oils D396-38T. ...... The specific gravity of oil is of interest in its relationship to the calorific value and these data are given in Table 8. COMBUSTION OF OIL With oil, as with any kind of fuel, efficient heat production requires that all combustible matter in the fuel shall be completely consumed and that it shall be done with a minimum of excess air. The combustion of oil is a rather rapid chemical reaction. Excess air provides an over supply of oxygen so that all of the oil, composed of carbon and hydrogen, will be completely oxidized and thus produce all the heat possible. The use of unreasonable quantities of air in excess of theoretical combustion require ments results in lowered efficiencies due to increased stack losses. Such 173 T ,,, , 7 D etailed R equirem en^ ^ ^ ^ ' CPNcmowKC cum ** ' I 1 1 c a c *, - 5* s>q.a"_u *'ta8osi'Ss- 3 Kh ci< t> B . g5C n 1 8.-9 Es'! 8Sg.fi e- &sj ||s > TJ ? ":S feO.Wfct, l/) c li ga-So 5 * :> a <3 O If* \4onJ*go3 tooi y g*o &S ,g %o\ '5 s|3l ?E3 J3X o u!*i X> & ,Pgg3aigpi gB gC S S x01 ^-8 c si-El Eg aE^sl&g'=a IS s^Hl|S2sgg||g &>Su8-So>ggg*atogcs^ a*3|&-aa>g ,,Oi O Cc3g^-"a gD0w*iOr2*X3)OCL- 0o *O3 Cg 1: I538Oo SfQ&t.*eS.J-tS3Soa3'0i-t&*.r_l0>P-lg1aa3!st&S3l?f'-ts3joij..'ctu-2g^o--3aeB---B^-a^"-^gSCg-t==fa-4fs--,g.32.-: it 1 ? 2 3 * 5tu3cH S&& o. s o si] tJ ?i2 .opof4, l-G rt.2 B g*C a; 3o> 3*C0fl i2!!! *I E2 gfaoa 5--H ^JyO 21 : l"g -o2-- f'S" "S'0 gtS s| rt >, `3 to o las 83R* J3 2q8 o 3*g5fl 55 |ll ****-C<it gc`a bo o o*. 3a O 174 CHAPTER 9. COMBUSTION AND FUELS losses, if not accompanied by unburned products of combustion (satu rated and unsaturated hydrocarbons, hydrogen, etc.) may be offset some what by increasing the secondary heating surfaces of the heat absorbing medium boiler or furnace. Oil is a highly concentrated fuel composed mainly of hydrogen and carbon. In its liquid form oil cannot burn. It must be converted into a gas or vapor by some means. If the excess air is to be kept within efficient limits it means that air must be supplied in carefully regulated quantities. The air and oil vapor must be vigorously mixed to get a rapid and com plete chemical reaction. The better the mixing, the less excess air that will be needed. The combustion must take place in a space that maintains the temperatures high s.o.the reaction will not be stopped before com pletion. When equipped with a means of igniting the oil and safety devices to guard against mishaps, the oil burner possesses all of the elements to be efficient and automatic. Table 8. Approximate Gravity and Calorific Value of Standard Grades of Fuel Oil Commercial Standard No. i 2 3 5 6 Approximate Gravttt, Range Baums 38-40 34-36 28-32 18-22 14-16 Calqsutw Vllto Btu Pee Gallon 136,000 138,500 141,000 148,500 152,000 CLASSIFICATION OF CAS Gas is broadly classified as being either natural or manufactured. Natural gas is a mechanical mixture of several combustible and inert gases rather than a chemical compound. Manufactured gas as dis tributed is usually a combination of certain proportions of gases produced by two or more processes, and is often designated as city gas. Repre sentative properties of gaseous fuels commonly used in domestic heating are presented in Table 9. Natural gas is the richest of the gases and contains from 80 to 95 per cent methane, with small percentages of the other combustible hydrocarbons. In addition, it contains from 0.5 to 5.0 per cent of CCk, and from 1 to 12 or 14 per cent of nitrogen. The heat values varies from 700 to 1500 Btu per cubic foot, the majority of natural gases averaging about 1000 Btu per cubic foot. Table 9 shows typical values for the four main oil fields, although values from any one field vary materially. Table 9 also gives the calorific values of the more common types of manufactured gas. Most states have legislation which controls the distri bution of gas and fixes a minimum limit to its heat content. The gross or higher calorific value usually ranges between 520 and 545 Btu per cubic foot, with an average of 535. A given heat value may be maintained and yet leave considerable latitude in the composition of the gas so that as distributed the composition is not necessarily the same in different dis-' tricts, nor at successive times in the same district. . 175 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 9. Representative Properties op Gaseous Fuels, , V, Based on Gas at 60 F and 30 in. Hg. Products op Combustion Gas Specific jRAVITT, foe Combos- Cubic Feet UltI' . HATE !>1AME TemPEfiATUHK, (Gross) (Net) 1.00. (Co Ft) COi ff0 Total with (DEO FaHR) Dry Basis N, Natural gas-- California , 1200 Natural gas--" Mid-Conti nental , : 967 Natural gas-- _ Ohio 1130 1087 873 1025 0.67. 11.26 -1.24 2.24 > ' 0.57 .. .9.17' . > *' 0.65 10,70 0.97 1.92 1.17 -2.16 12.4 10.2 11,8 12.2 3610 , 11.7 3580 . 12,1 . 3600 ; Natural gas-- Pennsylvania : Retort coal gas Coke oven gas .1232 1120 575 ... 510 588 521 0.71; 11.70 0.42 5.00 0.42 5.19 1.30 0,50 0.51 2.29 1,21 1.25 12.9 .5,7 5.9 12.3 11.2 11.0 3620 3665 _ 3660 Carbureted' ' water gas Blue water gas '536 308 496 0.65 281 0.53 4.37 2.26 0.74 0.75 0.46 0.51 5.0 17.2 2.8 22.3 3815 3800 Anthracite pro ducer gas 134 124 0.85 1.05 0.33 0.19 1.9 19.0 3000 Bituminous producer gas Oil gas 150 140 0.86 575 510 0.35 1.24 4.91 0.35 0.19 0.47 1.21 2.0 19.0 5.6 10.7 3160 3725 COMBUSTION OF GAS The majority of gas burners utilized in central domestic heating plants are: of the Bunsen type and operate with a non-luminous flame.. In this type of burner part of the air required for combustion is mixed with the gas as primary air, the air and gas mixture being fed to the burner ports. Additional secondary air is introduced around the flame by draft inspi ration. In the luminous flame burner, which is sometimes used, all of the air for combustion is brought in contact with the flame as secondary air. The importance of bringing the secondary air into intimate contact with the gas is noted. . Some makes of burners use radiants or refractories to convert some of the energy in the gas to radiant heat by utilizing the principle of surface combustion. The radiants also serve as baffles in directing the flow of the products of combustion. . Since one of the main functions of a gas burner is to properly proportion the air and gas, any marked change in the gas composition which affects the specific gravity necessitates a readjustment of the burner. It is necessary to supply a greater amount of air when the specific gravity of a gas is increased. 176. CHAPTER 9. COMBUSTION AND FUELS ! . , : The quantity of air given in Table 9 is that required for theoretical combustion, but with a properly designed.and installed burner the excess air can be kept low. The division of the air into primary and secondary is a matter of burner design and the pressure of gas available, and also of the type of flame desired. ,. The air gas ratio has a decided effect upon flame propagation. It is necessary that the gas will flow out of the burner ports fast enough so that the flame cannot travel back into the burner head, i.e. flash back, but the velocity must not be so high that it blows the flame away from the port: The maximum and minimum flow speeds from burner ports which may be permitted are known to be very close together when air-gas mixtures in theoretical proportions are being supplied to the burner. As the air-gas ratio is lowered, and the mixture becomes more gas rich, the limiting speeds become further apart, until with 100 per cent gas, in an all-yellow flame, flash back cannot occur and a much higher velocity is needed to blow off the flames. The deposit of soot on the flue surfaces of a boiler or heater acts as an insulating layer over the surface and reduces the heat transmission to the water or air; the Bureau of Mines Report of Investigations Ho. 3272 shows that the loss of seasonal efficiency is not as great as has been believed and usually is not over 6 per cent because the greater part of the heat is transmitted through the combustion chamber surfaces. The soot accumulation clogs the passages and reduces the draft; the loss of effi ciency from this action may be considerably greater than from the reduction in heat transfer. Fuels and Their Combustion, Haslam and Russell (McGraw Hill Co., 1926). Principles of Combustion in the Steam Boiler Furnace, Arthur D. Pratt, (Babcock and Wilcox Co.). Smoke-Producing Tendencies in Coals of Various Ranks, by H. J. Rose and F. P. Lasseter (A.S.H.V.E. Journal Section, Healing, Piping, and Air Conditioning, Febru ary, 1939, p. 119). Bureau of Mines Publications: Bulletin No. 97, Sampling and Analyzing Flue Gases, by Henry Kreisinger and F. K. Ovitz. Report of Investigations (R.I. 2980), Coke as a Domestic Heating Fuel, by P. Nicholls and B. A. Landry. Bulletin No. 276, Five Hundred Tests of Various Coals in House-heating Boilers, by P. Nicholls, S. B. Flagg and C. E. Augustine. Report of Investigations (R.I. 3283), Quality of Anthracite as Prepared at Breakers, 1935. Technical Paper No. 80, Hand Firing Soft Coal under Power-Plant Boilers, by Henry Kreisinger. Technical Paper No. 303, Value of Coke, Anthracite, and Bituminous Coal for Gener ating Steam in a Low-pressure Cast-iron Boiler, by John Blizard, James Neil and F. C. Houghten. 1771 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Anthracite Industries Laboratories Publications: .. Report 2015, Comparison of Sizes, Egg, Stove and Chestnut Anthracite. Report 2018, Domestic Survey. Report 2062, Utilization of Anthracite for Domestic Heating. Report 2204, The Crater Method of Firing. Report 2403, Anthracite Industries Manual. An Experimental Investigation of the Use of Oil for the Treatment of Coal, by Ralph A. Sherman and J. M. Pilcher {A.S.M.E. Transactions, February, 1938). Handbook of Oil Burning, by Harry F. Tapp, American Oil Burner Association. Industrial Gas Series, Combustion, American Gas Association. Comfort Heating, A merican Gas Association. Tests of Gas Home-Heating Equipment, by R. B. Leckie and C. H. B. Hotchkiss (Purdue University, Engineering Bulletin Research Series No. 36). 178 Chapter 10 CHIMNEYS AND DRAFT CALCULATIONS Natural Draft, Mechanical Draft, Characteristics of Natural Draft Chimneys, Determining Chimney Sizes, General Equa tion, Chimney Construction, Chimneys for Gas Dealing THE design and construction of a chimney is so important a part of the heating engineer's work that a general knowledge of draft characterictics and calculations is essential. Draft, in general, may be defined as the pressure difference between the atmospheric pressure and that at any part of an installation through which the gases flow. Since a pressure difference implies a head, draft is a static force. While no element of motion is inferred, yet motion in the form of circulation of gases throughout an entire boiler plant installation is the direct result of draft. This motion is due to the pressure difference, or unbalanced pressure, which compels the gases to flow. Draft is often classified into two kinds according to whether it is created thermally or artificially, viz, (1) natural or thermal draft, and (2) artificial or mechanical draft. Natural Draft Natural draft is the difference in pressure produced by the difference in weight between the relatively hot gases inside a natural draft chimney and an equivalent column of the cooler outside air, or atmosphere. Natural draft, in other words, is an unbalanced pressure produced thermally by a natural draft chimney as the pressure transformer and a temperature difference. The intensity of natural draft depends, for the most part, upon the height of the chimney above the grate bar level and also the temperature difference between the chimney gases and the atmosphere. A typical natural draft system consists essentially of a relatively tall chimney built of steel, brick, or reinforced concrete, operating with the relatively hot.gases which have passed through the boilers and accessories and from which all the heat has not been extracted. Hot gases are an essential element in the operation of a natural draft system, although inherently a heat balance loss. , A natural draft chimney performs the two-fold service of assisting in the creation pf draft by aspiration and also of discharging the gases at an elevation sufficient to prevent them from becoming a nuisance. Natural draft is quite advantageous in installations where the total loss of draft due to resistances is relatively low and also in plants which have " practically a constant load and whose boilers are seldom operated above si 179 . , . yg; i j ; i j I j j j ' ] j j ) ! j ' : i I j ! j HEATING VENTILATING AIR CONDITIONING GUIDE 1940 their normal rating. Natural draft systems have been, and are still being, employed in the operation of large plants during the periods when the boilers are operated only up to their normal rating. When the rate of operation is increased above the normal rating, some form of mechanical draft is employed as an auxiliary to overcome the increased resistances or draft losses. Natural draft systems are used almost exclusively in the smaller size plants where the amount of gases generated is relatively small and it would be expensive to install and operate a mechanical draft system. ' The principal advantages of natural draft systems may be summarized as follows: (1) simplicity, (2) reliability, (3) freedom from mechanical 048 |8 20 C F H IN 1000*8 . Fig. 1. General Operating Characteristics of Typical Induced Draft Fan parts, (4) low cost of maintenance, (5) relatively long life, (6) relatively low depreciation, and (7) no power required to operate. The principal disadvantages are: (1) lack of flexibility, (2) irregularity, (3) affected by surroundings, and (4) affected by temperature changes. Mechanical Draft Artificial draft, or mechanical draft, as it is more commonly called, is a difference in pressure produced either directly or indirectly by a forced draft fan, an induced draft fern, or a Venturi chimney as the pressure transformer. The intensity of mechanical draft is dependent for the most part upon the size of the fan and the speed at which it.is operated. The element of temperature does not enter into the creation of mechanical draft and therefore its intensity, unlike natural draft, is independent of the temperature of the gases and the atmosphere. Mechanical draft includes the induced and Venturi types of draft systems in which the pressure difference is the result of a suction, and also the forced draft system in which the pressure difference is the result of a blowing. Mechanical draft systems tend to produce a vacuum or a plenum, as the. system used in its production creates a pressure difference below, or above, atmospheric ISO . CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS Fig. 2. Operating Characteristics of Typical Centrifugal Pump pressure, respectively. A mechanical draft system may be used either in conjunction with, or as an adjunct to, a natural draft system. Draft Control To obtain the maximum efficiency of combustion, a definite minimum supply of air to the combustion chamber must be maintained. To pro vide this condition, it is necessary to have some mechanical means.of draft control or adjustment, because of variable wind velocities, fluctua tions in atmospheric temperatures and barometric pressures, and their effect upon draft. For this purpose there are various mechanical devices which auto-matically control the volume of air admitted to the combustion chamber. Mechanical draft regulators designed to control or adjust draft, should 4. T,,,cae S,, ,, 0m,TM Character,sue, o, , N.,,,,, 'm HEATING VENTILATING AIR CONDITIONING CUIDE 1940 not be confused with mechanical draft systems that create draft mechani cally, but which must also be automatically controlled. The use of such a device to provide a more uniform and dependable control of draft than could be maintained by manually operated dampers, will produce better combustion of fuel. This higher efficiency of combus tion together with the reduced heat losses up the chimney by reason of decreased gas velocity, results in fuel economy, with consequent lower costs of plant operation. CHARACTERISTICS OF CHIMNEYS In order to analyze the performance of a natural draft chimney, it may be advantageous to compare its general operating characteristics with those of a centrifugal pump and also of a centrifugally-induced draft fan, there being a similarity among the three. Figs. 1, 2 and 3 show the general operating characteristics of a typical centrifugally-induced draft fan, a typical centrifugal pump, and a typical natural draft chimney, respectively. The draft-capacity curve of the chimney corresponds to the head-capacity curve of the pump and also to the dynamic-headcapacity curve of the fan. When the gases in the chimney are stationary, the draft created is termed the theoretical draft. When the gases are flowing, the theoretical intensity is diminished by the draft loss due to friction, the difference between the two being termed the total available draft. The general equation for this net total available draft intensity of a natural draft chimney with a circular section is as follows: , where A = 2.96HB,, (~ 0.00126W'TcfL D^BoWc (1) Da = available draft, inches of water. ................... H = height of chimney above grate bars, feet. B0 = barometric pressure corresponding to altitude, inches of mercury. W0 -- unit weight of a cubic foot of air at 0 F and sea level atmospheric pressure, pounds per cubic foot. Wo = unit weight of a cubic foot of chimney gases at 0 F and sea level atmospheric pressure, pounds per cubic foot. To ~ absolute temperature of atmosphere, degrees Fahrenheit. To *= absolute temperature of chimney gases, degrees Fahrenheit. W ~ amount of gases generated in the combustion chamber of the boiler and passing through the chimney, pounds per second. / = coefficient of friction. L = length of friction duct of the chimney, feet. D = minimum diameter of chimney, feet. The first term of the right hand expression of Equation 1 represents the theoretical draft intensity, and the second term, the loss due to friction. Example 1. Determine the available draft of a natural draft chimney 200 ft in height and 10 ft in diameter operating under the following conditions: atmospheric tempera ture, 62 F; chimney gas temperature, 500 F; sea level atmospheric pressure, B0 = 29.92 in. of mercury; atmospheric and chimney gas density, 0.0863 and 0.09, respectively; coefficient of friction, 0.016; length of friction duct, 200 ft. The chimney discharges 100 lb of gases per second. . 182 CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS Substituting these values in Equation 1 and reducing: Do 2.96 X 200 X 29.92 X (- ~863 0.09N V 522 960 / 0.00126 X 100* X 960 X 0.016 X 200 10* X 29.92 X 0.09 , = 1-27 - 0.14 = 1.13 Fig. 3 shows the variation in the available draft of a typical 200 ft by 10 ft chimney operating under the general conditions noted in Example 1. When the chimney is under static conditions and no gases are flowing, the available draft is equal to 1.27 in. of water, the theoretical intensity. As the amount of gases flowing increases, the available intensity decreases until it becomes zero at a gas flow of 297 lb per second, at which point the draft loss due to friction is equal to the theoretical intensity. The draftcapacity curve corresponds to the head-capacity curve of centrifugal Fig. 4. Relation Between BakometkicPressuke.and Altjtodh pump characteristics and the dynamic-head-capacity curve of a fan. The point of maximum draft and zero capacity is called shut-off draft, pr point of impending delivery, and corresponds to the point of shut-off head of a centrifugal 'pump/ The point of zero draft and maximum capacity js called the wide open point and corresponds to the wide open point of "a centrifugal pump. A set of operating characteristics may be developed for any size chimney operating under any set of conditions by substituting the proper values in Equation 1 and then plotting the results in the manner shown in Fig. 3. ' In substituting the values for the various factors in Equation 1, care should be exercised that the selections be as near the actual conditions'as is practically possible. The following notes will serve as a guide.for these selections: ...... . _ 1. The barometric pressure varies inversely as the altitude of the plant;above sea level. Fig. 4 gives the barometric pressure corresponding to various elevations as computed from the equation: ..... r . : - where Ei = 62,737 log,, -=!-- . ... *>o Ei = altitude of plant above sea level, feet; ;. . .: (2) 183 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 In general, the barometric pressure decreases approximately 0.1 in. of mercury, per 100 ft increase in elevation. 2. The unit weight of a cubic fool of chimney gases at 0 F and sea level barometric pressure is given by the equation: Wc = 0.131 CO, + 0.095 0, + 0.083 Nt (3) In this equation CO,, O, and AT, represent the percentages of the parts by volume of the carbon dioxide, oxygen and nitrogen content, respectively, of the gas analysis. For ordinary operating conditions, the value of Wc may be assumed at 0,09.: The density effect on the chimney gases due to superheated water vapor' resulting from moisture and hydrogen in the fuel, or due to any air infiltrations in the chimney proper are here disregarded. Though water vapor content is not disclosed by Orsat analysis, its presence tends to reduce the actual weight per cubic foot of chimney gases. 3. The atmospheric temperature is the actual observed temperature of the outside air at the time the analysis of the operating chimney is made. The mean atmospheric temperature in the temperate zone is approximately 62 F. 4. The chimney gas temperature does not vary appreciably from the gas temperature as it leaves the breeching and enters the chimney. For average operating conditions, the chimney gas temperature will vary between 500 F and 650 F except in the case when economizers and recuperators are used, when the temperature will vary between 300 F and 450 F. If a chimney has been properly constructed, properly lined and has no air infiltration due to open joints, the temperature of the gases throughout the chimney will not differ appreciably from the foregoing figures. In most up-to-date heating plants, the temperature may be read from instruments or ascertained from a pyrometer. The analysis of this section is predicated on the assumption of constant gas temperature and no air infiltration throughout the height of the chimney. 5. The coefficient of friction between the chimney gases and a sooted surface has been taken by many workers in this Held as a constant value of 0.016 for the conditions in volved. This value, of course, would be less for a new unlined steel stack than for a brick or brick-lined chimney, but in time the inside surface of, all chimneys regardless of the materials of construction becomes covered with a layer of soot, and thus the coef ficient of friction has been taken the same for all types of chimneys and in general constant for all conditions of operation. For reasons of simplicity and convenience to the reader, this constant value of 0.016 has been employed in the development of the various special equations and charts shown in this chapter. 1 : .. However, much to be recommended as an alternate method is the practise, of separ ately determining duct friction factors as a function of the flow conditions, specifically as a function of the Reynolds number and the relative duct roughness. The Reynolds criterion is based on the physical properties of the gas, the duct dimensions, and the gas velocity. The gas velocity for a chimney is usually well above the'critical velocity. It is likely that this procedure of using a separately determined variable friction factor for chimney flow will give results that are to be preferred over those' based on a set constant. .. ' ' " . . . . '. The Reynolds number, a dimensionless ratio, may be stated as follows: : DVP Ct . V- (4) where 3 -- chimney diameter, feet. V = velocity of hot gas, feet per second. 0 = mass density.of the chimney gas per cubic foot. p = viscosity of the gas in pounds-second per sqtfare foot taken at the gas tem perature. In another form: 1,27 W = 0.0396 W Dv-g D\i (5) 184 CHAPTER 10. CHIMNEYS AND DRAFT' CALCULATIONS where ' W = weight of gas passed per second. g acceleration of gravity. . ' . The value of a for chimney gases is usually taken as that of air or nitrogen, and for the variation of p with temperature, the Sutherland equation may be employed as follows, giving p in pounds-second per square foot: . 11 _ LT2f7c3 ++Cnj rL 2f7c3 HJ -S where Tc = chimney gas temperature, degrees Centigrade, po = gas viscosity at 0 C. C = constant for specific gas. Using International Critical Table values, for air po = 35.6 X 10-8; C = 124- for nitrogen po = 34.5 X 10-8; and C = 110. ' Fig. 5. Variation of Friction Factor / with Reynolds Number Values for the viscosity of air and of nitrogen (the .principal component of chimney gases) for the different temperatures follow, in which the values given in pounds-second per square foot ate to be. multiplied by 10-8; ' : . . Temp. F Air Nitrogen 300 49.7 47.7 400 54.5 52.2 500 58.5 56.0 600 62.5 59.8 700 66.7. 63.5 800 70.5 67.0 Example 8. To determine the Reynolds number CT for a flow of 118 lb gas per second up a 12 ft diameter chimney at a temperature of 500 F. The gas may be assumed to have the same viscosity as nitrogen at 500 F. Using Equation 5: Cr w = 0.0396 Dp = 0.0396 X 118 12 X 56.0 X 10-8 = 698,000 The variation of the friction factor / with the Reynolds number is shown in Fig. 5*. Three curves are shown: A, B, and C, where the choice of the friction factor curve depends on the relative surface roughness, and this for usual chimney construction may Set also Flow of Fluids in Closed Circuits, by R. J. S. Pigott (Mtchanical Engineering. August. 1933). 185 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 be selected by size since surface conditions in service are always undeterminant. For sizes up to 3 ft in diameter. Curve C may be used; from 3 to 6 ft, Curve B; and from 6 ft upwards, Curve A. Thus for the previous example with Cr = 698,000 and 12 ft diameter, / w6o.ulTdhbeelteankgethn ofrfotmheCfruicrvtieonAdausc0t .i0s03th9e. vertical distance between the bottom of the breeching opening and the top of the chimney. Ordinarily this distance is approximately equal to the height of the chimney above the gTate level. mT . FlG' 6' Cbimney Performance Charts , CgGW'tp w = 3600 where Cg = pounds of fuel burned per square foot of grate surface per hour. G = total grate surface of boilers, square feet. ' , ., Cg X G = total Weight of fuel burned per hour. :. Wtp = total weight of products of combustion per pound of fuel. , . thp -age of gas, oil, or Stoker-fired fuel. A similar computation may be made i 186 CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS Fig. 6 is a typical chimney performance chart giving the available draft intensities for various amounts of gases flowing and sizes of chimney. This chart is based on an atmospheric temperature of 62 F, a chimney gas temperature of 500 F, a unit chimney gas weight of 0.09 lb per cubic foot, sea level atmospheric pressure, a coefficient of friction of 0.016, and a friction duct length equal to the height of the chimney above the grate level. These curves may be used for general operating conditions. For specific operating conditions, a new chart should be constructed from Equation 1. It has been the usual custom, and still is to a lamentably great extent, to select the required size of a natural draft chimney from a table of chimney sizes based only on boiler horsepowers. After the ultimate horsepower of the projected plant had been determined, the chimney size in the table corresponding to this figure was then selected as the proper size required. Generally, no further attempt was made to determine if the height thus selected was sufficient to help create the required draft demanded by the entire installation, or the diameter sufficiently large to enable the chimney quickly, efficiently, and economically to dispose of the gases. Since the operating characteristics of a natural draft chimney are similar in all.respects to those of a centrifugal pump, or a centrifugal fan, it is no more possible to select a proper size chimney from such a table, even with correction factors appended, than it is to select the proper size pump from tables.based only on the amount of water to be delivered. DETERMINING CHIMNEY SIZES The required diameter and height of a natural draft chimney are given by the following equations; H = Dr *(?!-If)-si.m/fycB0vt TCD (7) wkere = .0.288 y WTC B,,WCV (8) H = required height of chimney above grate bar level, feet. D = required minimum diameter of chimney, feet (constant for entire height). V -- chimney gas velocity, feet per second. Dt ~ total required draft demanded by the entire installation outside of the chimney, inches of water. Equations 7 and 8 give the required size of a natural draft chimney with all of the operating factors taken into consideration. Values for all of the factors with the exception of the chimney gas velocity may be either observed or computed. It is, of course, necessary to assume an arbitrary value for the velocity in order to arrive at some definite size. For any one set of operating conditions there will be as many sizes of chimneys as there are values of reasonable velocities to assume. Of the number of sizes corresponding to the various assumed velocities, there is one size which will be least expensive. Since the cost of a chimney structure, regardless 187 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 of the kind of material used in the construction, varies as the volume of material in the structure, the cost criterion then may be represented by the approximate equation: . Q = xtHD (9) where. Q -- volume of material, cubic feet. t =; average wall thickness, feet. For all practical purposes, the value of xt may be taken as a constant regardless of the size of the structure. Hence, in general, the volume, and consequently the cost, of a chimney structure may be based on the factor HD as a criterion. Therefore, the value of the chimney gas velocity which will result in the least value of HD for any one set of operating con ditions will produce a structure which will be the most economical to use, because its cost will be least. The problem at hand is to deduce an equation for the chimney gas velocity which will result in a combination of a height and a diameter whose product HD will be least. The solution is obtained by equating the product of Equations 7 and 8 to HD, differentiating this product with respect to V and equating the resulting expression to zero. This pro cedure results in the following expression: . where Vc = economical chimney gas velocity, feet per second. Equation 10 gives the economical velocity of the chimney gases for any set of operating conditions, and represents the velocity which will result in a chimney the size of which will cost less than that of any other size as determined by any other velocity for the same operating con ditions. After the value of the economical velocity has been determined, the corresponding height and diameter can then be determined from Equations 7 and 8, respectively, and the economical size will then be attained. Equations 7, 8 and 10 may be simplified considerably for average operating conditions in an average size steam plant by assuming typical conditions. Average chimney gas temperature, 500 F____ ___________ 7c = 960 Mean atmospheric temperature, 62 F......................... ......... T0 = 522 Average coefficient of friction, 0.016________________ -f = 0.016 Average chimney gas density, 0.09._____________ _____ = 0.09 Sea level elevation, with barometer of 29.92._____________B0 = 29.92 Substituting these values in Equations 10, 8 and 7, respectively, and reducing, the results are substantially: = 13.7W,1/5 (11) D = 1.5W2/s (12) H = 190Dt (13) 188 CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS Fig. 7 gives the economical chimney sizes for various amounts of gases flowing and for required draft intensities as computed from Equations 11, 12 and 13. They are based on the operating factors used in reducing Equations 7, 8 and 10 to their simpler form. The sizes shown by the curves in the chart should be used for general operating conditions only, or for installations where the required data necessary for an exact deter- Height of Chimney, ft. Fig. 7. Economical Chimney Sizes3 ^Diameter values also for gas temperatures of 400, 500 and 600 F mination are difficult or impossible to secure. Whenever it is possible to secure accurate data, or the anticipated operating conditions are fairly well known, the required size should be determined from Equations 7, 8 and 10. The recommended minimum inside dimensions and heights of chimneys for small and medium size installations are given in Table 1. GENERAL EQUATION The general draft equation for a steam producing plant may be stated as follows: Dt - k = h? + hB + hBd + he + hBr + hv + ho + &E + Ar 189 . (14) HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 where Dt = theoretical draft intensity created by pressure transformer, inches of water. hi = draft loss due to friction in pressure transformer, inches of water. hF = draft loss through the fuel bed, inches of water. hB = draft loss through the boiler and setting, inches of water. Abt = draft loss through the breeching, inches of water. hv = draft loss due to velocity, inches of water. hBd .= draft loss due to bends, inches of water. JiC = draft loss due to contraction of opening, inches of water. ho = draft loss due to enlargement of opening, inches of water. hE = draft loss through the economizer, inches of water. Ar -- draft loss through recuperators, regenerators, or air heaters, inches of water. The left hand member of Equation 14 represents the total amount of available draft created by the pressure transformer, that is, the natural draft chimney, Venturi chimney, or fan, and is equal to the theoretical intensity less the internal losses incidental to operation. The right hand member represents the sum of all of the various losses of draft throughout the entire boiler plant installation outside of the pressure transformer itself. The left hand member expresses the available intensity and is analogous to the head developed by a centrifugal pump in a water works system, while the right hand member expresses the required draft in tensity and is analogous to the total dynamic head in a water works system. For a general circulation of gases Da = Dr (15) where Z>a = available draft intensity, inches of water. Dr * required draft, inches of water. The draft loss through thefuel bed (for), or the amount of draft required to effect a given or required rate of combustion, varies between wide limits and represents the greater portion of the required draft. In coal-fired installations, the draft loss through the fuel bed is dependent upon the following factors: (1) character and condition of the fuel, clean or dirty; (2) percentage of ash in the fuel; (3) volume of interstices in the fuel bed, coarseness of fuel; (4) thickness of the fuel bed, rate of combustion; (5) type of grate or stoker used; (6) efficiency of combustion. There is a certain intensity of draft with which the best results will be obtained for every kind of coal and rate of combustion. Fig. 8 gives the intensity of draft, or the vacuum in the combustion chamber required to burn various kinds of coal at various rates of combustion. Expressed in other words, these curves represent the amount of draft required to force the necessary amount of air through the fuel bed in order to effect various rates of combustion. It will be noted that the amount of draft increases as the percentage of volatile matter diminishes, being comparatively low for the lower grades of bituminous coals and highest for the high grades and small sizes of anthracites. Also, when the interstices of the coal are large and the particles are not well broken up, as with bituminous coals, much less draft is required than when the particles are small and are well 190 CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS broken up, as with bituminous slack and the small sizes of anthracites. In general, the draft loss through the fuel bed increases as: (1) the per centage of volatile matter diminishes! (2) the percentage of fixed carbon increases; (3) the thickness of the bed increases; (4) the percentage of ash increases; (5) the volume of the interstices diminishes. In making the preliminary assumptions for the draft loss through the fuel bed, due allowances should be made for a possible future change in the grade of fuel to be burned and also in the rate of combustion. A value Table 1. Recommended Minimum Chimney Sizes for Heating Boilers and Furnaces Wash Am Fubnacb Capacitt in 8q In. op Lbadsb Pipe Steam Bozleb Capacity Sq Ft op Radi* ation Hot Watkh Heatxr Capacitt Soft o* Radi- Anoir 790 1000 590 690 900 900 1,100 1.700 1,940 2,130 2,480 3,150 4,300 4,600 5,000 5,570 5,580 6,980 7,270 8.700 9,380 10,150 10,470 973 1,140 1,490 1,490 1,820 2,800 3.200 3,520 4,090 5.200 7,100 7,590 8,250 9,190 9.200 11.500 12,000 14,400 15.500 16,750 17,250 Nominal Dimen sions or Fma Clai Lining in Inches Rectanqulab Flub Actual Inside Dimensions of Fire Clay fining in Inches Actual Area Sq In. 8)4 x 13 7 xllM 81 13x13 8)4 x 18 13x18 n%xii% 6%xl6% Il%xl6% 127 110 183 18x18 15*4x15% 248 20x20 n%xn% 298 20x24 24x24 17x21 21x21 24 x24b 357 441 576 24 x 28b 28 x 28b 30x 30b 28 x 32b 672 784 900 896 Round Flub Inside Diam eter of lining in Indies Actual Area Sq In. 10 79 12 113 15 177 18 254 20 314 22 380 24 452 27 573 Height in Ft Above Grate 35 40 45 50 55 60 65 This table is taken from the A.S.H.V.E. Code of Minimum Requirements for the Heating and Venti lation of Buildings (Edition of'1929). ' ' ... . . ^Dimensions are for unlined rectangular flues. * -; : should be selected,for. this loss which .will represent not only the highest rate of combustion which:will be encountered, but also the grade of coal which has the greatest resistance through the fuel bed and which may be burned at a later date. i. . ' .f In powdered-fuel and oil-fired installations, there will be no draft loss through the fuel bed since there is none and, consequently, this factor becomes zero. in the general* draft equation. All other factors being constant, the height of the chimney in installations of this character will be less than the height in coal-fired installations, and in the case of* me chanical draft installations the driving units need not be as large since the head against which the fan:is to operate'is not as great in the former as in the latter. * .' - '* ., 191 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The draft loss through the boiler and setting (ha) also varies between wide limits and, in general, depends upon the following factors: 1. Type of boiler. 5. Arrangement of baffles. 2. Size of boiler. 3. Rate of operation. 6. Type of grate. 7. Design of brickwork setting. 4. Arrangement of tubes. 8. Excess air admitted. 9. Location of entrance into breeching. Curves showing the draft loss through the boiler are usually based on the load or quantity of gases passing through the boiler, expressed in terms of percentage of normal rate of operation. Owing to the great variety'of boilers of different designs and the various schemes of baffling, it is impossible to group together a set of curves for the draft loss through O 9 1U J3 CU xg gv V .. . POUNDS OF COAL BURNED PER SQ FT OF GRATE SURFACE PER HOUR Fig. 8. Draft Required at Different Rates of Combustion ' for Various Kinds of Coal ' the boiler which may even be used generally. It is therefore necessary to secure this information from the manufacturer of the particular type of boiler and baffle arrangement under consideration. When a boiler is installed and in operation, the draft loss depends upon the amount of gases flowing through it- This, in turn, depends upon the proportion of excess air admitted for combustion.. Primarily, the amount of excess air is measured by the COi content; the less the amount of COt, the greater the amount of excess air and hence the greater the draft loss. The loss of draft through the boiler will vary directly as the size of the boiler andthe length of the gas passages within. The loss also varies as the-number of tubes high, but not in a direct ratio inasmuch as the loss due to the,reversal of flow at the ends of the.baffles remains constant regardless of the height of the boiler. The arrangement of the tubes, whether the. gases flow parallel to or at right angles to the tubes, has an appreciable effect on the loss. The arrangement of the baffles influences the draft loss greatly, the loss through a boiler with five passes being ' 192 CHARTER 10; CHIMNEYS AND DRAFT CALCULATIONS greater than the loss through one of three or four passes: -A poor design and a rough condition of the brickwork will increase'the loss greatly,' whereas a proper design and a smooth condition. will keep the loss at aminimum. The loss through the boiler will be less when the breeching entrance is located at or near the top of the boiler than when it is located at or near the bottom since the gases have a shorter distance to travel in the former instance. The draft loss through the breeching (/iBr) is given by the' general equation: where _ o.ooomg^rc/L ., : A'BaWcCbT (16) W = the amount of gases flowing, pounds per second. . , ,. ., , Tc = absolute temperature of breeching gases, degrees Fahrenheit. / = coefficient of friction. . .... . L = length of breeching, feet: A = area of breeching, square feet. ' Bo = atmospheric pressure corresponding to altitude, inches of mercury. . Wc = weight of a cubic foot of breeching gases at 0 F and sea level atmospheric pressure, pounds per cubic foot. ' . .. Cbr = hydraulic radius of breeching section: ` It has been the general custom to lump off the intensity of the breeching loss at 0.10 in. of water per 100ft of breeching length regardless of its size or shape or the amount and temperature of the gases flowing through it. This practice is hazardous and has no more foundation in fact than that of determining the friction head in a water works system without taking into consideration the size of the pipe or the amount of water flowing through it. When the length of the breeching is relatively short, any variation in any one of the factors in the equation will have no appreciable effect on the draft loss. However,' when the breeching is relatively long, the draft loss is affected greatly by the various factors, particularly by the size and shape as well as by the weight of gases flowing. The draft loss due to velocity {hy) is given by the equation hv 0.000194W*Tc A*B0WC (17) and represents the amount of draft required to accelerate the gases from zero velocity to the velocity at which the gases are flowing, or in other words, from a static-gas condition of zero flow to the amount of gases flowing throughout'the installation. This loss corresponds to the velocity head in water works systems. The draft loss due to bends (hnd) is equivalent to the loss due to the velocity head for a 90-deg bend. In changing direction of flow, the gas velocity decreases to zero with a loss of velocity head and then increases to its proper value at the expense of a loss in pressure head, the net result being a loss in pressure head equal to the velocity head at the bend. This loss is given by the equation: *Bd 0.000194PF*rc A`B0 Wc 193 (18) HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The friction at a right-angle bend is sometimes expressed as the equivalent of a straight length of flue of a certain length for a certain diameter, similar to the procedure used in estimating the loss due to bends in piping systems conducting water. Most flues, however, par ticularly breechings, are built square or rectangular in section and no general equation based on the shape of the flue can be conveniently expressed. The draft loss due to sudden contraction of an area (he) is given by the equation: 0.000194STC W*TC he = .i,, w , (19) where Kc = coefficient of sudden contraction based on the ratio of the areas of the A.\ smaller to the larger section = 0.5 ^ 1 -- ^ As = area of the smaller section. - When the flue or passage through which the gases flow is suddenly contracted, a considerable portion of the static head in the larger section is converted into velocity head and a draft loss of some consequence, par ticularly in a short breeching, takes place. A sudden contraction should always be avoided where possible.. At times, however, due to obstruc tions or limited head-room, it is necessary to alter the size of the breeching, but a sudden contraction may be avoided by gradually decreasing the area over a length of several feet. . The draft loss due to a sudden enlargement of an area (ho) is given by the equation: o:oooi94g0tyrc ho = a\b0wc ." (20) where Ka - coefficient of sudden enlargement based on --Al , the ratio of the areas of the / A' smaller to the larger section When the flue or passage through which the gases flow is suddenly enlarged, a portion of the velocity head is converted into static head in the larger section and, like the loss due.to sudden contraction, a loss of some consequence, particularly in short breechings, takes place. A sudden enlargement in a breeching may be avoided by gradually increasing the area over a length of several feet. In large masonry chimneys, the area of the flue at the region of the breeching entrance 5s considerably larger than the area of the breeching at the chimney, and a sudden enlargement exists. The draft loss through the economizer (&e) should be obtained from the manufacturer but for general purposes it may be computed from the following general equation: : Ae = -6.6^ivrc (21) 194 CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS where Wn = pounds of gases flowing per hour per linear foot of pipe in each economizer . section. N = number of economizer sections. An economizer in a steam plant affects the draft in two ways, (1) it offers a resistance to the flow of gases, and (2) it lowers the average chimney gas temperature, thereby decreasing the available intensity. In the case of a natural draft installation, both of these factors result in a relative increase in the height of the chimney and, in the case of a large pljMit, they may add as much as 20 or 30 ft to the height. The decrease in the temperature of the gases after they have passed through the economizer has an extremely important effect on the performance of a natural draft chimney and also upon the performance of a fan. CONSTRUCTION DETAILS For general data on the construction of chimneys reference should be made to the Standard Ordinance for Chimney Construction of the National Board of Fire Underwriters. Briefly summarized, these provisions are as follows for heating boilers and furnaces: The construction, location, height and area of the chimney to which a heating boiler or warm-air furnace is connected affect the operation of the entire heating system. Most residence chimneys are built of brick and may be either lined or unlined, but in either case the walls must be air-tight and there should be only one smoke opening into the chimney. Cleanout, if provided, must be absolutely air-tight when closed. The walls of brick chimneys shall be not less than in. thick (width of a standard size brick) and shall be lined with fire-clay flue lining. Fire-clay flue linings shall be manufactured from suitable refractory clay, either natural or compounded, and shall be adapted to withstand high temperatures and the action of flue gases. They shall be of standard commercial thickness, but not less than M in. All fire-clay flue linings shall meet the standard specification of the Eastern Clay Products Association. The flue sections shall be set in special mortar, and shall have the joints struck smooth on the inside. The masonry shall be built around each section of lining as it is placed, and all spaces between masonry and linings shall be completely filled with mortar. No broken flue lining shall be used. Flue lining shall start at least 4 in. below the bottom of smoke- pipe intakes of flues, and shall be continued the entire heights of the flues and project at least 4 in. above the chimney top to allow for a 2 in. projection of lining. The wash or splay shall be formed of a rich cement mortar. To improve the draft the wash surface should be concave wherever practical. Flue lining may be omitted in brick chimneys, provided the walls of the chimneys ^ess ^ thick, and that the inner course shall be a refractory clay brick. AH brickwork shall be laid in spread mortar, with all joints push-filled. Exposed joints both inside and outside shall be struck smooth. No plaster lining shall be permitted. Chimneys shaU extend at least 3 ft above flat roofs and 2 ft above the ridges of peak r0 f when such flat roofs or peaks are within 30 ft of the chimney. The chimney shall be high enough so-that the wind from any direction shall not strike the top of the chimney from an angle above the horizontal. The chimney shall be properly capped with stone, terra cotta, concrete, cast-iron, or other approved material; but no such cap or coping shall decrease the flue area. : . There shall be but one connection to the flue to which the boiler or furnace smokepipe is attached. The boiler or furnace smoke-pipe shall be thoroughly grouted into the chimney and shall not project beyond the inner surface of the flue lining. The size or area of flue lining or of brick flue for warm-air furnaces depends on height of chimney and capacity of heating system. For chimneys not less than 35 ft in height above grate line, the net internal dimensions of lining should be at least 7 x llj^ in. 195 HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 for a total leader pipe area up to 790 sq in. Above 790 and up to 1,000 sq in. of leader pipe area the lining should be at least 1134 x 1134 in. inside. In case of brick flues not less than 35 ft in height with no linings, the internal dimensions should be at least 8 x 12 in. up to 790 sq in. of leader area, and at least 12 x 12 in. for leader capacities up to 1,000 sq in. Chimneys under 35 ft in height are unsatisfactory in operation and hence should be avoided. CHIMNEYS FOR CAS HEATING The burning of gas differs from the burning of coal in that the force which supplies the air for combustion of the gas comes largely from the pressure of the gas in the supply pipe, whereas air is supplied to a bed of burning coal by the force of the chimney draft. If, with a coal-burning boiler, the draft is poor, or if the chimney is stopped, the fire is smothered and the combustion rate reduced. In a gas boiler or furnace such a condition would interfere with the combustion of the gas, but the gas would continue to pass to the burners and the resulting incomplete com bustion would produce a dangerous condition. In order to prevent incom plete combustion from insufficient draft, all gas-fired boilers and furnaces should have a back-draft diverter in the flue connection to the chimney. Table 2. Suggested General Dimensions for Vertical Back-Draft Diverter CHAPTER 10. CHIMNEYS AND DRAFT CALCULATIONS A study of a typical back-draft diverter shows that partial or complete chimney stoppage will merely cause some of the products of combustion to be vented out into the boiler room, but will not interfere with com bustion. In fact, gas-designed appliances must perform safely under such a condition to be approved by the American Gas Association Laboratory. Other functions of the back-draft diverter are to protect the burner and pilot from the effects of down-drafts, and to neutralize the effects of . variable chimney drafts, thus maintaining the appliance efficiency at a substantially constant value. Converted boilers or furnaces, as well as gas-designed appliances, should be provided with back-draft diverters. Since back-draft diverters have a special function to perform in pro tecting gas burning appliances, it is necessary that they should be built to the proper size as shown in Table 2 for a vertical type and in Table 3 - for a horizontal arrangement. Equipment of this kind listed by the American Gas Association Testing Laboratory must bear the listing symbol A.G.A. Table 3. Suggested General Dimensions for Horizontal Back-Draft Diverter Pip* Sis* . A B 3 33 .4 4 4 5 5, 5 6 66 7 77 8 88 9 99 10 10 10 11 11 11 12 12 12 cDE S.5 7.2 9.4 11.S 13. S 15.5 17.5 19.7 22.2 24.7 7.0 3.8 9.5 5.0 10.8 5.3 12.0 5.6 13.9 6.4 15.8 7.1 17.5 . 7.7 18.8 7.9 20.7 8.4 22.2 8.7 f" G H I J KLM 0.7, 1.0 1.5 1.9 2.3 2.7 3.1 3.6 4.3 5.0 4.4 6.0 8.0 9.8 11.6 13.4 15.2 17.2 19.6 22.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 1.5 2.5 0.7 1.5 2.3 2.0 3.5 1.0 2.0 3.0 2.3 4.0 0.9 2.4. 3.5 2.5 4.5 0.8 2.7 4.0 2.9 5.3 0.9 3.1 4.6 3.2 6.0 1.0 3,5 5.3 3.5 6.7 1.0 4.0 5.8 3.8 7.3 1.0 4.3 6.2 4.1 8.0 1.5 4.6 6.6 4.4 8.5 1.7 5.0 7.0 Table of Dimensions (In.) So* A B c D 1 EF G 1 H J KLM 3 4 5 6 7 8 9 10 . 11 12 3 4 5 6 7 8 9 10 11 12 3 4 5 6 7 8 9 10 11 12 6 1.5 8 2.0 10 2.5 12 3.0 14 3.5 16 4.0 18. 4.5 20 5.0 22 5.5 24 6.0 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 3.8 5.0 6.3 7.5 8.8 10.0 11.3 12.5 13.8 15.0 1:4 1.9 2.4 2.9 3.4 3.9 4.4 4.9 5.4 5.9 2.5 3.4 4.2 5.0 5.9 6.7 7.5 8.4 9.2 10.0 2.5 3.4 4.2 5.0 5.9 6.7 7.5 8.4 9.2 10.0 2.5 3.4 4.2 5.0 5.9 6.7 7.5 8.4 9.2 10:0 2.1 2.9 3.5 4.3 5.0 5.6 6.4 7.0 7.8 8.5 0.6 0.8 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 1.8: 2.3 2.9 3.5 4.1 4.7 5.3 5.8 6.4 7.0 197 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 As is the case with the complete combustion of almost all fuels, the products of combustion for gas are carbon dioxide (Cft) and water vapor with just a trace of sulphur trioxide (SO3). Sulphur usually burns to the trioxide in the presence of an iron oxide catalyst. The volume of water vapor in the flue products is about twice the volume of the carbon dioxide, when coke oven or natural gas is burned. Because of the large quantity of water vapor which is formed by the burning of gas, it is quite important that all gasdired central heating plants be connected to a chimney having a good draft. Lack of chimney draft causes stagnation of the products of combustion in the chimney and results in the condensation of a large amount of the water vapor. A good chimney draft draws air through the openings in the back-draft diverter, lowers the dew-point of the mixture, and reduces the tendency of the water vapor to condense. The flue connections from a gas-fired boiler or furnace should be of a non-corrosive material. In localities where the price of gas requires Table 4. Minimum Round Chimney Diameters for Gas Appliances (Inches) Height of Chmnet Feet 100 Gas Consumption in Thousands of Btu per Hour 200 300 400 500 750 1000 1500 2000 ` 20 40 60 . 80 100 4.SO 4.2s 4.10 4.00 3.90 5.70 5.50 5.35 5.20 5.00 6.60 6.40 6.20 6.00 5.90 7.30 7.10 6.90 6.70 6.50 8.00 7.80 7.60 7.35 7.20 9.40 9.15 8.90 8.65 8.40 10.50 10.25 10.00 9.75 9.40 12.35 12.10 11.85 11.50 11.00 13.85 13.55 13.25 12.85 12.40 highly efficient appliances, the material used for the flue connection should not only be resistant to the corrosion of water but should resist the corrosion of dilute solutions of sulphur trioxide. Local practice should be followed in the selection of the most appropriate flue materials. When condensation in a chimney proves troublesome, it may be necessary to provide a drain to a dry well or sewer. The cause of the excessive condensation should be investigated and remedied if possible. This may be done by raising the flue temperature slightly or increasing the size of the back-draft diverter. The protection of unlined chimneys has been investigated and the results indicate that after the loose material has been removed, the spraying with a water emulsion of asphaltchromate provides an excellent protection. A chimney for a gas-fired boiler or furnace should be constructed similarly to the principles applicable to other boilers. Where the wall forming a smoke flue is made up of less than an 8-in. thickness of brick, concrete, or stone, a burnt fire-clay flue tile lining should be used. Care should be used that the lengths of flue tile meet properly at the joints. Cement mortar should be used for the entire chimney. Table 4 gives the minimum cross-sectional diameters of round chim neys (in inches) for various amounts of heat supplied to the appliance, and for various chimney heights. This is in accordance with American Gas Association recommendations. . Chapter 11 AUTOMATIC FUEL BURNING EQUIPMENT Classification of Stokers, Combustion Process and Adjust ' ments. Furnace Design, Classification of Oil Burners, Combus tion Chamber Design, Classification of Gas-Fired Appliances AUTOMATIC mechanical equipment for the combustion of solid, liquid and gaseous fuels is considered in this chapter. MECHANICAL STOKERS A mechanical stoker is a device that feeds a solid fuel into a combustion chamber, provides a supply of air for burning the fuel under automatic control and, in some cases, incorporates a means of removing the ash and refuse of combustion automatically. Coal can be burned more efficiently by a mechanical stoker than by hand firing because the stoker provides a uniform rate of fuel feed, better distribution in the fuel bed and positive control of the air supplied for combustion. Stokers may be divided into four types according to their construction, namely, (1) overfeed flat grate, (2) overfeed inclined grate, (3) underfeed side cleaning type, and (4) underfeed rear cleaning type. Overfeed Flat Crate Stokers This type is represented by the various chain- or traveling-grate stokers. These stokers receive fuel at the front of the grate in a layer of uniform thickness and move it back horizontally to the rear of the furnace. Air is supplied under the moving grate to carry on combustion at a sufficient rate to complete the burning of the coal near the rear of the furnace. The ash is carried over the back end of the stoker into an ashpit beneath. This type of stoker is suitable for small sizes of anthracite or coke breeze and also for bituminous coals, the characteristics of which make it desirable to burn the fuel without disturbing it. This type of stoker requires an arch over the front of the stoker to maintain ignition of the incoming fuel. Frequently, a rear combustion arch is required to main tain ignition until the fuel is fully consumed. A typical traveling-grate stoker is illustrated in Fig. 1. Another and distinct type of overfeed flat-grate stoker is the spreader (Fig. 2) or sprinkler type in which coal is distributed either mechanically or by air over the entire grate surface. This type of stoker has a wide application on small sized fuels and on certain special fuels such as lignites, high-ash coals, and coke breeze. 199 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Overfeed Inclined Crate Stokers In general the combustion principle is similar to the flat-grate stoker, but this stoker (Fig. 3) is provided with rocking grates set on an incline to advance the fuel during combustion. Also this type is provided with an ash plate where ash is accumulated and from which it is dumped periodi cally. This type of stoker is suitable, for all types of coking fuels but preferably for those of low volatile content. Its grate action has the tendency to keep the fuel bed well broken up thereby allowing for free CHAPTER II. AUTOMATIC FUEL BURNING EQUIPMENT the volatile gases are released, are mixed with air, arid pass through the fire where they are burned. The ash may be continuously discharged as in the small stoker or may be accumulated on a dump plate and periodi cally discharged. This stoker requires no arch as it automatically pro vides for the combustion of the volatile gases. . passage of air. Because of its agitating effect on the fuel it is not so desirable for badly clinkering coals. Furthermore, it should usually be provided with a front arch to care for the volatile gases. Underfeed Side Cleaning Stokers In this type (Fig. 4), the fuel is introduced at the front of the furnace to one or more retorts, is advanced away from the retort as combustion progresses, while finally the ash is disposed of at the sides. This type of stoker is suitable for all coking coals while in the smaller sizes it is suitable for small sizes of anthracites. In this type of stoker the fuel is delivered, to a retort beneath the fire and is raised into the fire. During this process 200 Underfeed Rear Cleaning Stokers !' This type of stoker accomplishes combustion in much the same manner as the side cleaning type, but consists of several retorts placed side by side and filling up the furnace width, while the ash disposal is at the rear. In principle, its operation is the same as the side cleaning underfeed. Stokers also may be classified according to their size based upon coal feed rates. The following classification has been made by the United Slates Department of Commerce in cooperation with the Stoker Manu facturers' Association. Class 1. Up to and including 60 lb of coal per hour. Class 2. 60 to 100 lb of coal per hour. 201 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Class 3. 100 to 300 lb of coal per hour. .. Class 4.. 300 to 1200 lb of coal per hour. . : (A fifth class is included covering stokers having a feeding capacity above 1200 lb of coat per hour). .. Class 1 and Class 2 Stokers, Household Since these stokers are used primarily for home heating, it is desirable that their design be simple and attractive in appearance, and that they be quiet and automatic in operation. CHAPTER 11. AUTOMATIC FUEL BURNING EQUIPMENT Certain types can also be provided with a coal conveyor which takes coal from the storage bin and maintains a full hopper at the stoker. In some cases the coal bin functions as the stoker hopper as shown in Fig. 7, and an extended worm is used to convey the fuel to the combustion furnace. Domestic stokers may feed coal to the furnace either intermittently or with a continuous flow regulated automatically to suit conditions. Household stokers are made for all classes of fuel; anthracite, bitu minous and semi-bituminous coals, and coke. The United Stales Depart ment of Commerce has issued commercial standards for household anthra cite burned, which may be obtained by application. Standards of performance for bituminous coal stokers are also being developed by Bituminous Coal Research, Inc. The standards for anthracite stokers are described in the next paragraphs. Fig. 6. Underfeed Screw Stoker with Automatic Ash Removal A common type of stoker in this class consists, essentially of a coal reservoir or hopper, a screw for conveying the fuel from the hopper to the burner head or retort, a fan which supplies the air for combustion, a transmission for driving the coal feed worm, arid an electric motor or motors for supplying the motive power for both coal feed and air supply as indicated in Fig. 5. The shape of the retort in this class of stokers is usually round although rectangular retorts are favored by some manu facturers. In all cases, however, the retort incorporates tuyeres through which the air for combustion is admitted. Some household stokers are provided with an automatic grate-shaking mechanism together with screw .conveyors for removing the ash from the ashpit (Fig. 6) and depositing it in an ash receptacle outside the boiler. 202 Operating Requirements for Anthracite Stokers Efficiency. The over-all efficiency of the unit at all points above 50 per cent of maxi mum coal feed shall be above 50 per cent when installed in a round sectional cast-iron boiler having three intermediate sections and in. of asbestos insulation or its equiva lent in good condition of repair, operating at 50 per cent or more of the boiler capacity. The efficiency shall be maintained for any continuous period of.4 hours during any test or observation run. . Ask Loss. Combustible in ash shall not exceed 7.5 per cent of the Btu content of the coal as fired at any rate of coal feed above 50 per cent of maximum. Subsequent to the issuance of these standards the Society adopted a Code* which should be followed in all details applicable to stoker testing. . Clinker. Ash removing systems should at all times be capable of disposing of any clinker which may be formed under any conditions of operation with the coals prescribed. Combustion Rale. A combustion rate of at least 13 lb per square foot of horizontal projected area of. ash ring per hour must be continuously maintained for at least 9 hours with the above conditions of efficiency, ash and clinker. . Flue Gas. Flue gas shall be not below 6 per cent in carbon dioxide with a reasonably tight boiler at any rate of operation above 50 per cent of maximum coal feed. - Maximum Rating. The maximum rating, in terms of gross square feet of water or steam radiation which the burner will supply, when intended for installation in the average existing cast-iron boiler, shall be 90 per cent of the maximum steam produced in a round cast-iron boiler in good repair having three intermediate sections and the equivalent of in. of asbestos insulation. However, in no case shall the maximum rating be greater than 29 sq ft of direct steam radiation for each pound of coal fired per hour, and in no case shall ratings be based upon efficiency figures below 50 per cent. Vol!A4'f'"93SEpS.366)ard Code for Testins Stoker-Fired Steam-Heating Boilers (A.S.H.V.E. Transactions. 203 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The maximum rating as defined in the preceding paragraph shall be based upon com bustion of Pennsylvania anthracite.having, the following approximate analysis: Volatile matter 3.5 to 9 percent; ash content not to exceed 15 per cent; sulphur content Under 1.5 per cent; ash fusing temperature 2750 F, or above (volatile, ash and sulphur content on dry basis in accordance with A .S. T. M. method D271-33); Btu content 12,000 or above; properly sized as follows: A No. 1 buckwheat should pass through a round mesh screen having c in. holes and over a similar screen having 'Xg in. holes. The undersizing should not exceed 15 per cent and the oversizing should not exceed 10 per cent. A No. 2 buckwheat (rice) should pass through a round mesh screen having holes 9^6 ,n- in diameter and over a like screen having holes of X6 in. in diameter. The under sizing, should not exceed 15 per cent and the oversizing should not exceed 10 per cent. Coal Storage It is recommended that the coal bin or closet be constructed so as to bedustproof. . Electrical Consumption. The electrical consumption shall not exceed 18 kwhr per 2000 lb of coal burned at any rate of coal feed above 50 per cent of the maximum. Operation Upon Other Sizes of Coal. The foregoing specifications have been drafted for operating with the Nos. 1 and 2 buckwheat sizes ot anthracite. In the event that other sizes are recommended, ratings shall be based upon the same efficiency and ash loss requirements. ' Banking. The burner shall be so constructed or controlled as to maintain a fire during an indefinite banking period. Acceleration. When the burner resumes operation after a 12 hour banking period, the time required for the stack temperature to reach a normal maximum shall not exceed 60 min. Stoker-Fired Units Boilers and air conditioners especially designed for stokers are now becoming available. Present designs feature better coordination between the heat absorber and the stoker. Increased setting height and furnace volume and more heating surface than in conversion installations are usually to be found in these stoker units. Class 3 Stokers, Apartment House, Small Commercial This class is used extensively for heating plants in apartments and hotels, and also for small industrial plants such as laundries, bakeries, and creameries. The majority of stokers used in this field are of the underfeed type. The principal exception is an overfeed type having step action grates in a horizontal plane and so arranged that they are alternately moving and stationary, and are designed to advancethe fuel during com bustion to an ash plate at the rear. All of the stokers are provided with a coal hopper outside of the boiler. In the underfeed types, the coal feed from this hopper to the furnace may be accomplished by a continuously revolving screw or by an intermittent plunger. The drive for the coal feed may be an electric motor, or a steam or hydraulic cylinder. With an electric motor, the connection between the driver and the coal feed may be through a variable speed gear train which provides two or more speeds for the coal feed; or it may be through a simple gear train and a variable speed driver for the change in speed of the coal feed; or a simple gear train with a coal feed having an adjustment for varying the travel of the feeding device. With a steam or hydraulic cylinder, the power piston is connected directly to the coal feeding plunger. The stokers in this class vary also in their retort design according to the fuels and load conditions. The retort is placed approximately in the 204 CHAPTER 11. AUTOMATIC FUEL BURNINC EQUIPMENT middle of the furnace and is provided with tuyere openings at the top on all sides. In the plunger-feed type the retort extends from the inside of the front wall entirely to the rear wall or to within a short distance of the rear wall. This type of retort has tuyeres on the sides and at the rear. These stokers also differ in the grate surface surrounding the retort. In many of the worm-feed stokers this grate is entirely a dead plate on which the fuel rests while combustion is completed. In the dead-plate type, all of the air for combustion is furnished by the tuyeres at the retort. Because of this, combustion is well advanced over the retort so that it may easily be completed by the air which percolates through the fuel bed. With the dead-plate type of grate the ash is removed through the fire doors and it is therefore desirable that the fuel used shall be one in which the ash is readily reduced to a clinker at the furnace temperature, in order that it may be removed with the least disturbance of the fuel bed. In other stokers in this class, the grates outside of the retort are airadmitting and some stokers have shaking grates. These grates permit a large part of the ash to be shaken into the ashpit beneath, while the clinkers are removed through the fire doors. With this type of grate, the main air chamber extends only under the retort while the side grates receive air by natural draft from the ashpit. In still other stokers of this class, the main air chamber extends beyond the retort and is covered with fuel-bearing, air-supplying grates. With this type of grate, the fuel is supplied with air from the main air chamber throughout combustion. Also with this type of grate, dump plates are provided beyond the grates where the ash accumulates and from which it can be dropped periodically into the ashpit beneath. . Stokers in this class are compactly built in order that they may fit into standard heating boilers and still leave room for sufficient combustion space above the grates. The height of the grate is approximately the same as that of the ordinary grates of boilers, so that it is usually possible to install such stokers with but minor changes in the existing equipment. In some districts, there are statutory regulations governing such settings. These stokers vary in furnace dimensions from 30 in. square to approxi-. mately 66 in. square. The capacity of the stokers is measured by the amount of coal that can be burned per hour. In general, manufacturers recommend that, for continuous operation, the coal burning rate shall not exceed 25 lb of coal per square foot of grate per hour, while for short peaks this rate may be increased to 30 lb per hour. Although these stokers were designed to burn bituminous coal, types are available for the semi-bituminous coals such as Pocahontas and New River. They can also be used to burn the small sizes of anthracite but at a somewhat lower rate. Class 4 Stokers, Medium Commercial These stokers are usually of the screw feed type without auxiliary plungers or other means of distributing the coal. Rectangular retorts with sectional tuyeres and dead plates without air ports are employed: The unit type of construction is almost universally used, the unit incor porating the hopper, the transmission for driving the feed screw, and the fan for supplying air for combustion. 205 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Class 4 Stokers, Large Commercial, Small High Pressure Plants Stokers in this group vary widely in details of mechanical design and the several methods of feeding coal previously described may be employed Such methods of applying power to the fuel conveying mechanism as, continuous gear train transmission, ratchet-type speed reducer, hydraulic cylinder and steam cylinder are used. Varying methods of ash disposal are found in this class. Large Stokers This class includes stokers with hourly burning rates of over 1200 lb of coal per hour. The prevalent stokers in this field are: (a) overfeed flat grate, (b) overfeed inclined grate, (c) underfeed side cleaning, and (d) underfeed rear cleaning. Overfeed inclined grate stokers are seldom built in sizes of over 500 hp and are not as extensively used as other types of stokers. Underfeed side cleaning stokers are made in sizes up to approximately 500 hp and in this field are extensively used. These stokers are not so varied in design as those in the smaller classes although the principle is much the same. Practically all of them are of the front coal feed type, either power driven or steam driven. Dump plates at the side are manually operated. These stokers are heavily built and designed to operate continuously at high boiler ratings with a minimum amount of attention. Because of the fact that all volatile gases must pass through the fire before reaching the combustion chamber, these stokers will operate smokelessly under ordinary conditions. Also because of the fact that these stokers are always provided with forced draft, they are the most desirable type for fluctuating loads or high boiler ratings. In the design of the grates for supporting the fuel between the retort and the ash plates, the stokers differ in providing for movement of the fuel during combustion. Some stokers are designed with fixed grates of sufficient angle to provide for this movement as the bed is agitated by the incoming fuel, while others have alternate moving and stationary bars in this area and provide for this movement mechanically. In either type, with proper operation, all refuse will be deposited at the dump plate. Recent developments in this type of stoker provide for sliding distributor blocks along the bottom of the retorts which give flexibility in providing proper distribution of fuel over the grate area and assist in preventing coke masses when strong coking coals are used. Another difference in these stokers is that some use a single air chamber under the whole grate area thus having the same air pressure under the ignition area as under the rest of the grate, while others have a divided air chamber using the full air pressure under the ignition area and a reduced air pressure under the remainder of the grate. These stokers vary in size from approxi mately 5 sq ft to a maximum of 8}4 sq ft. The most prevalent type of rear cleaning underfeed stoker is the multiple retort design. Occasionally double or triple retort side cleaning underfeeds are made. The multiple retort underfeed stoker is made for the largest sizes of boilers for large industrial plants and central stations. This stoker has reached a very fine stage of development mechanically and in the matter of air supply and control. In some instances zoned air 206 CHAPTER 11. AUTOMATIC FUEL BURNING EQUIPMENT control has been applied both longitudinally and transversely to the grate surface. Ash dumps on smaller sizes are sometimes manually operated. The Combustion'Process Due to the marked differences in design and operating characteristics of stokers and the widely differing characteristics of stoker fuels, it is difficult to generalize on the subject of combustion in automatic stokers; In anthracite stokers, which are almost exclusively of the small (Class 1) underfeed type, burning takes place within the stoker retort. The ash and refuse of combustion spills over the edge of the retort into an ashpit or receptacle from which it may be removed either manually or auto matically. Anthracite is usually supplied for stoker firing in No. 1 buckwheat or No. 2 buckwheat size. Those stokers burning coke operate in' a similar manner to anthracite stokers. Since the majority of bituminous coal stokers used in heating plants operate on the underfeed principle some general observations of their operation are given. When the coal is fed from the hopper or bin into the retort it is generally degraded to some extent and some segregation of sizes occurs. Because of these factors there may be some difference in the actions occurring in the various portions of the retort. The coal moving upward in the retort toward the zone of combustion established by previous kindling of the fire is heated by conduction and radiation from the zone of combustion. As the temperature of the coal rises it first gives off moisture and occluded gases, which are largely, non-combustible. When the temperature increases to around 700 or 800 F, the coal particles become plastic, the degree of plasticity varying with the type of coal. . A rapid evolution of combustible volatile matter occurs during and directly after the plastic stage of the coal. The distillation of volatile matter continues above the plastic zone and the coal is coked. The strength and porosity of the coke formed will vary according to the size and characteristics of the coal used. As more coal is fed from below the mass of coke continues , to grow forming a coke tree, plug or spar as it is variously designated. After a period of time, dependent upon the strength of the coke formed, pieces of the coke tree break off and fall upon the hearth surrounding the retort or within the retort itself where they are burned. While part of the ash fuses into particles at the surface of the coke as it is released, most of it is freed in unfused flakes or grains. The greater part of this unfused ash remains on the hearth or dead plates although a part may be expelled from the furnace with the gases. The ash layer becomes thicker with time and that near the retort, being exposed to temperatures which are high enough at times, fuses into a clinker. The temperature attained in the fuel bed, the chemical compo sition and homogeneity of the ash, and the time of heating are factors which govern the degree of fusion. . Bituminous coal stokers of the Class 1 type operate on. the principle of the removal of ash as clinker and clinker tongs are provided to facilitate HEATING VENTILATINC AIR CONDITIONING CUIDE 1940 this purpose. Typical representations of underfeed bituminous stoker fuel beds are shown in Figs. 8 and 9. The appearance of such fuel beds is very ragged at times, and large masses of coke build up, surrounded by blowholes -with intense white flame indicating the presence of excess air. ; There is a natural tendency for users to disturb the fuel bed and make it conform to the conventional representation or ideal fuel bed. Such attention should not be required, as usually the fuel bed tends to correct its own faults as the cycles of plasticity, coke free formation and ash fusion recur. . There are a number of factors which materially affect the rate anditype * of combustion obtained in stoker usage, the most important of these being: the: type and design of stoker, the type and characteristics of the fuel, the method of stoker installation,and the method of stoker operation;. Fig. 8. Cross-Section of Fuel Bed ' with Weakly Coking Coal Fig. 9. Cross-Section of Fuel Bed with Strongly Coking Coal Furnace Design The burning of the fuel on the grate or in the retort will be influenced directly by the stoker design. The burning of the volatile gases above the fuel bed is a matter of furnace design. Proper care should be taken to provide furnaces sufficiently liberal in volume and with the grates or retorts at a sufficient distance from the heating surface to permit proper combustion of the gases. Smoke and low efficiency will result if the furnace is too small to permit proper mixing of the gases and completion of combustion. ' The standard that has been most commonly used for the proportioning of furnaces for bituminous coal stokers is the code of the Steel Heating Boiler Institute (see Chapter 13). Furnace volume is not an important item in anthracite stoker instal lations. Due care should be exercised for both anthracite and bituminous stokers to prevent intense heat application on the metal surfaces of the combustion chamber. The installation of a baffle or adjustment in setting 1 height of the stoker may be desirable in some cases. 208 CHAPTER II. AUTOMATIC FUEL BURNINC EQUIPMENT The prime essentials of good furnace design are: correct proportions, moderate combustion rate, adequate furnace volume and sufficient flame clearance. If these factors are properly compensated for and provision is made for the proper mixing of the gases bituminous coal stokers will operate smokelessly. In those stokers which are operated intermittently, however, some smoke may be produced during the off periods. .. . Combustion Adjustments Satisfactory stoker performance may be secured by regulating the coal feed and the air supply so as to maintain, as nearly as possible, an ideal balance between the load demand and the heat liberated by the fuel. When the coal is consumed at about the same rate as that which it is fed this balance exists and uniform fuel bed conditions will be found. Under Y such conditions no manual attention to the fuel bed should be required other than the removal of clinker in those stokers which operate on this principle of ash removal. Since complete combustion is not obtained in stoker furnaces receiving only the air theoretically required, it is necessary, even under the best of conditions, to supply from 30 to 50 per cent excess air to obtain desired combustion results. Due to the variable characteristics of solid fuels in burning, consideration must be given to a number of factors which affect the maintenance of the combustion conditions wanted. The specified.rate of coal feed of a stoker may vary due to changes in the bulk density of the coal-dependent upon: (a) the size of coal, (b) dis tribution of size in the coal, (c) segregation of coal in the stoker hopper, and (d) friability of the coal. The following factors may affect the rate of air supply: (a) changes in fuel bed conditions and resistance, (6) changes in.furnace draft due to.a variety of causes, i.e,, changes in chimney draft because of weather changes, seasonal changes, back drafts, -failure or inadequacy of auto matic draft regulator, use of chimney for other purposes, possible stoppage of the chimney and changes in draft resistance of boiler due to partial stoppage of the flues, and (c) changes in air inlet adjustments to the fan. Many domestic bituminous stokers now incorporate some method of automatic control which compensates for changes in fuel bed resistance. Since a secondary source of air due to leakage is present in most installa tions, the use of an automatic draft regulator to maintain the furnace draft at about 0.05 in. of water is desirable. This is quite important withintermittently operated stokers. Some fuel is burned by natural draft in the off periods, when fuel is not being fed, and it is essential that the burning in these periods be controlled. With excessive draft, due either to fan pressure or chimney pull, an increase in the discharge of soot and fly ash from the combustion chamber will result. Measurement of the Efficiency of Combustion As efficient combustion is based upon a certain percentage of excess air, it is possible to determine the results by analysis of the gases formed by the combustion process. An Orsat apparatus can be used to determine the percentage (by volume) of the carbon dioxide (C02), oxygen (02) and carbon monoxide (CO) in the flue gases. Due to variations in the fuel bed 209 ^T.NC VENTILATING AIR CONDITIONING CmPM^O and rate of burning of stoker-fired solid fuels it is not sufficient to analyze a grab sample. A continuous gas sample drawn at a constant rate through out an operating period of reasonably long duration should be used. A COi reading of 12.5 to 14 per cent indicates that the excess air supplied is in the range of 30 to 50 per cent. The presence of CO indicates a loss due to improper mixing of the air and the gases of combustion. As an increase in excess air maintained during on periods will decrease the tendency toward smoke in the off periods of intermittently operated bituminous coal stokers, care should be taken that the delivery of air by the fan is great enough to avoid smoke. * CoTnhtreolsindustry developed by stokers in Classes 1,2,3 and 4 has been due as much to the application of proper controls as to the stoker itself. This is especially true of Class 1 stokers because of their application to resi dential heating, a field wherein the mjaority of owners and users are not familiar with control problems or stoker operation. The usual controls applied are: (a) thermostats, (6) limit controls, (c) stack temperature or time controls, (d) relays, (e) safety or overload cutouts, and (J) low water cutouts. DOMESTIC OIL BURNERS An oil burner is a mechanical device for producing heat automatically and safely from liquid fuels. This heat is produced in the furnace or firepot of hot water or steam boilers or warm air furnaces and is absorbed by the boiler, and thus made available for distribution to the house through theTheantiunmgbseyrsotefmc.ombinations of the characteristic elements of domestic oil burners is rather large and accounts for the variety of burners found in actual practice. Domestic oil burners may be classified as follows: 1. AIR SUPPLY FOR COMBUSTION a. Atmospheric--by natural chimney draft. b. Mechanical--electric-motor-driven fan or blower. c. Combination of (a) and (fr)--primary air supply by fan or blower and secondary air supply by natural chimney draft. 2. METHOD OF OIL PREPARATION a. Vaporising---oil distills on hot surface or in hot cracking chamber. b. Atomising--oil broken up into minute globules. ' . (1) Centrifugal--by means of rotating cup or disc. (2) Pressure--by means of forcing oil under pressure through a small (3) Ainroozrzlseteoarmo--rifibcye. high velocity air or steam jet in a special type of (4) Conmozbzinlea. tion air and pressure--by air entrained with oil under pressure and forced through a nozzle. c. Combination of (a) and (b). ; 3. TYoP. ELuOmFinoFuLsA--MaErelatively bright flame- An orange-colored flame is usually best if no smoke is present. g 4. Non-lvminous--Bunsen-type flame (i.e., blue flame). - 210 CHAPTER II. AUTOMATIC FUEL BURNINC EQUIPMENT 4. METHODS OF IGNITION o. Electric.- : (1) Spark--by transformer producing high-voltage sparks. Usually shielded to avoid radio interference. May take place continuously while the burner is operating or just at the beginning of operation. (2) Resistance--by means of hot wires or plates. b. Gas. (1) Continuous--pilot light of constant size. (2) Expanding--size of pilot light expanded temporarily at the beginning of burner operation. c. Combination--electric sparks light the gas and the gas flame ignites the oil. d. Manual--by manually-operated gas torch for continuously operating burners. 5. MANNER OF OPERATION a. On and off--burner operates only a portion of the time (intermittent). b. High and loco--burner operates continuously but varies from a high to a low flame. c. Graduated--burner operates continuously but flame is graduated according to needs by regulating both air and oil supply. rAMHOtlStm Fig. 10. Gun Type Pressure Atomizing Oil Burner A trade classification of oil burners consists- of the following general types: (a) gun or pressure atomizing, iff) rotary and (c) pot or vaporizing. The gun type, illustrated in Fig. 10 is characterized by an air tube, usually horizontal, with oil supply pipe centrally located in the tube and arranged so that a spray of atomized oil is introduced and mixed in the combustion chamber with the air stream emerging from the air tube. A variety of patented shapes are employed at the end of the air tube to influence the direction and speed of the air and thus the effectiveness of the mixing process. ;. . The most distinguishing feature of vertical rotary burners is the principle of flame application. These burners are of two general types; the center flame and wall flame. In the former type, (Fig. 11) the oil.is atomized by being thrown from the rim of a revolving disc or cup and the flame burns in suspension with a characteristic yellow color. Combustion is supported by means of a bowl-shaped chamber or hearth. The wall 211 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 flame burner (Fig. 12) differs in that combustion takes place in a ring of refractory material, which is placed around the hearth. .These types of burners are further characterized by their installation within the ashpit of the boiler or furnace. . The pot type burner (Fig. 13) can be identified by the presence of a metal structure, called a pot or retort, in which combustion takes fflace. When gun type (pressure atomizing) or horizontal rotary burners are CHAPTER M. AUTOMATIC FUEL BURNING EQUIPMENT Boiler-Burner Units ; Boilers and air conditioners especially designed for oil burners are available to the purchaser of this type of equipment. They are used for replacements as well as for new installations. This type of equipment usually has more heating surface than the older coal-burning designs. Flue proportions and gas travel have been changed with beneficial results. All problems of combustion chamber design, capacities, efficiencies, etc., have been solved. The selection of the proper size of unit should be a simple process. COMMERCIAL OIL BURNERS Liquid fuels are used for heating apartment buildings, hotels, public and office buildings, schools, churches, hospitals, department stores, as Fig. 11. Center Flame Vertical Rotary Burner Fig. 12. Wall Flame Vertical Rotary Burner used the combustion chamber is usually constructed of firebrick or other suitable refractory material, and is part of the installation procedure: - ' The oil burners are operated by a small electric motor which pumps the oil and some or all of the air required. The smallest sizes can generally burn not much less than 1 gal of oil per hour. The grade of oil burned ranges from No. 1 to No. .3. No. 3 oil is the heaviest and most viscous of the various grades mentioned. An oil burner satisfactory for No. 3 oil can burn any of the lighter grades easily but an oil burner recommended for No. 2,oil should never be supplied with the heavier grades. ' It has been found that while the heavier grades-of oil have a smaller heat value per pound, they have, due to greater density, a larger heat value per gallon.' The relative economy of the various grades must be based upon price and. 1 the amount of. excess air required for clean and efficient combustion. 212 well as industrial plants of all kinds. Contrary to domestic heating, con venience seldom is a dominating factor, the actual net cost of heat pro duction usually controlling the selection of fuel. Some of the largest office buildings have been using oil for many years. Many department stores have found that floor space in basements and sub-basements can be used to better advantage for merchandising wares, and credit the heat pro ducing department with this saving. . . '. Wherever possible, the boiler plant should be so arranged that either oil or solid fuel can be used at will, permitting the management to take advantage of changes in fuel costs if any occur. Each case should be considered solely in the light of local conditions and prices. Burners for commercial heating may be either large models of types used in domestic heating, or special types developed to meet the condi tions imposed by the boilers involved. Generally speaking, such burners are of the mechanical or pressure atomizing types, the former using rotating cups producing a horizontal torch-like flame. (Fig. 14). As much as 350 gal of oil per hour can be burned in these units, and frequently they 213 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 are arranged in multiple on the boiler face, from two to five burners to each boiler. The larger installations are nearly always started with a hand torch, and are manually controlled, but the useof automatic control is increasing,, and completely automatic burners are now available to burn the two heaviest grades of oil. Nearly all of the smaller installations, in schools, churches, apartment houses and the like, are fully automatic. Because of the viscosity of the heavier oils, it is customary to heat them before transferring by truck tank. It also has been common practice to preheat the oil between the storage tank and the burner, as an aid to movement of the oil as well as to atomization. This heating is accomplished . by heat-transfer coils, using water or steam from the heating boiler, and heating the oil to within 30 deg of its flash point. Unlike the domestic burner, units -for large commercial applications frequently consist of atomizing nozzles or cups mounted on the boiler front with the necessary air regulators, the pumps for handling the oil and the blowers for air supply being mounted in sets adjacent to the boilers. In such cases, one pump set can serve several burner units, and common prudence dictates the installation of spare or reserve pump sets. Pre-heaters and other essential auxiliary equipment also should be in stalled in duplicate. Boiler Settings ' As the volume of space available for combustion is the determining factor in oil consumption, it is general practice to remove grates and extend the combustion chamber downward to include or even exceed the ashpit volume; in new installations the boiler should be raised to make added volume available. Approximately 1 cu ft of combustion volume should be provided for every developed boiler horsepower, and in this volume from 1.5 to 2 lb of oil can properly be burned. This cor responds to a maximum liberation of about 38,000 Btu per cubic foot per hour. There are indications that at times much higher fuel rates may be satisfactory. This in turn suggests that the value of 38,000 Btu per cubic foot per hour might be adjusted according to good engineering judgment. For best results, care should be taken to keep the gas velocity below 40 ft per second. Where checkerwork of brick is used to provide secondary air, good practice calls for about 1 sq in. .of opening for each pound of oil fired per hour. Such checkerwork is best adapted to fiat flames, or to conical flames that can be spread over the floor of the combustion chamber. The proper bricking of a large or even medium sized boiler for oil firing is important and frequently it is advisable to consult an authority on this subject. The essential in combustion chamber design is to provide against flame impingement upon either metallic or fire brick surfaces. Manufacturers of oil burners usually have available detailed plans for adapting their burners to various types of boilers; and such information should be utilized. . The Combustion Process ` Efficient combustion, as previously indicated, must produce a. clean ' flame and must use relatively small excess of air, i.e., between 25 and 50 per cent. This can be done only by vaporizing the oil quickly, completely,' 214 CHAPTER 11. AUTOMATIC FUEL BURNING EQUIPMENT and mixing it vigorously with air in a combustion chamber hot enough to support the combustion. A vaporizing burner prepares the oil, for combustion, by transforming the liquid fuel to the gaseous state through the application of heat. This is accomplished before the oil vapor mixes with air to any extent and if the air and oil vapor temperatures are high and the fire pot hot, a clear blue flame is produced. There may be a deficiency of air as shown by the presence of carbon monoxide (CO) or an excessive supply of air, depending upon burner adjustment, without altering the clean, blue appearance of the flame. An atomizing burner i.e., gun and rotary types is so named because the oil is mechanically separated into very fine particles so that the surface exposure of the liquid to the radiant heat of the combustion chamber is vastly increased and vaporization proceeds quickly. The result of such practice is the ability to burn more and heavier oil within a given com bustion space or furnace volume. Since the air enters the fire pot with the liquid fuel particles, it follows that mixing, vaporization and burning are all occurring at once in the same space. This produces a luminous instead of a blue or non-luminous flame. In this case a deficient amount of air is indicated by a dull red or dark orange flame with smoky flame tips. An excessive supply of air may produce a brilliant white flame in some cases or, in others, a short ragged flame with incandescent sparks flashing through the combustion space. While extreme cases may be easily detected, it is generally not possible to distinguish, by the eye alone, the finer adjustment which competent installation requires. Certain tests indicate that there is no difference in economy between a blue flame and a luminous flame if the position, shape and the per cent of excess air of both flames are about the same. Furnace or Combustion Chamber Design The furnace or combustion chamber may be defined as that part of a boiler or conditioner in which combustion is established. With burners requiring a refractory combustion chamber the size and shape should be in accordance with the manufacturer's instructions. It is important that the chamber shall be as nearly air tight as is possible, except when the particular burner requires a secondary supply of air for combustion. It is evident that the atomizing burner is dependent upon the surround ing heated refractory or fire brick surfaces to vaporize the oil and support combustion. While the importance of the combustion chamber is obvious, its design has been troublesome. Unsatisfactory combustion may be due to inadequate atomization and mixing. A combustion chamber can only compensate for these things to a limited extent. If liquid fuel continually reaches some part of the fire brick surface, a carbon deposit will result. Fundamentally, the combustion chamber should enclose a space having a shape similar to the flame but large enough to avoid flame contact. The nearest approach in practice is to have the bottom of the combustion . chamber flat but far enough below the nozzle to avoid flame contact, . the sides tapering from the air tube at the same angle as the nozzle spray and the back wall rounded. A plan view of the combustion chamber thus resembles in shape the outline of the flame. In this way as much fire brick as possible is close to the flame so it may be kept quite hot. This insures quick vaporization, rapid combustion and better mixing by eliminating 215 HEATING VENTILATING. AIR CONDITIONING CUIDE 1940 dead or inactive spaces in the combustion chamber. An overhanging arch at the back of the fire pot is sometimes used to increase the flame travel and give more time for mixing and burning and sometimes to pre vent the gases from going too directly into the boiler flues. When good atomization and vigorous mixing are achieved by the burner, combustion chamber design becomes a less critical matter. Where secondary air is used, combustion chamber design is quite important. With some of the vertical rotary burners considerable care must be exercised in definitely following the manufacturers instructions when installing the hearth as in this class successful performance depends upon this factor. Combustion Adjustments Where adjustments of oil and air have been made which give efficient combustion, the problem of maintaining the adjustments constant be comes an important one. Particularly is this true when the change causes the per cent of excess air to decrease below allowable limits of the burner. A decrease in air supply while the oil delivery remains constant or an increase in oil delivery while the air supply remains constant will make the mixture of oil and air too rich for clean combustion. The more efficient the adjustment (i.e., 25 per cent excess air) the more critical it will be of variations. The oil and air supply rates must remain constant. The following factors may influence the oil delivery rate: (a) changes in oil viscosity due to temperature change or variations in grade of oil delivered, (b) erosion of atomizing nozzle, (c) fluctuations in by-pass relief pressures and (d) possible variations in methods 2b (3) and 2b (4) listed in the previous classification table. Note that any change due to partial stoppage of oil delivery will increase the proportion of excess air. This will result in less heat, reduced economy and possibly a complete inter ruption of service but usually no soot will form. The following factors may influence the air supply: (a) changes in combustion draft due to a variety of causes (i.e., changes in chimney draft because of weather changes, seasonal changes, back drafts, failure or inadequacy of automatic draft regulator, use of chimney for other purposes, possible stoppage of the chimney and changes in draft resis tance of boiler due to partial stoppage of the flues), and (b) changes in air inlet adjustments to the fan. It is recognized that a secondary source of air due to leakage in the boiler setting is present in many installations and it is highly desirable that this leakage be reduced to a minimum. Obviously the amount of air leakage will be determined by the draft in the combustion chamber. It is important that this draft should be reduced as low as is consistent with the proper disposal of the gases of combustion. When using mechani cal draft burners with average conditions, the combustion chamber draft should not be allowed to exceed 0.02-0.05 in. water. An automatic draft regulator is very helpful in maintaining such values. Measurement of the Efficiency of Combustion Efficient combustion being based upon a clean flame and certainproportions of oil and air employed, it is possible to determine the results) by analyzing the gases formed by the combustion process. An Orsat 216 CHAPTER 11. AUTOMATIC FUEL BURNING EQUIPMENT apparatus is a device which measures the volume of carbon dioxide (COj), oxygen (Os)'and carbon monoxide (CO) in. the flue gases. Except in the case of a non-luminous flame it is usually sufficient to analyze only for carbon dioxide (OOj). A showing of 10 to 12 per cent indicates the best adjustment if the flame is clean. Most of the good.installations at the present time show from 8 to 10 per cent COt. Taking into account the potential hazard of oil or- air fluctuations with low excess air. (high COi) a setting to give 10 per cent COt constitutes a reasonable standard for most oil burners. This is particularly true of non-luminous flame burners which will not function properly with less than 10 per cent CO%. Controls Oil burner controls may be divided into two parts: (a) devices to regulate burner operation so the desired house heating result may be obtained, and (V) devices for the safety and protection of the boiler and burner. For control devices generally consult Chapter 38. The room thermostat has recently been improved to provide more frequent burner operation and greater uniformity of room temperature. Class (b) controls comprise a device to shut off the burner if the oil fails to ignite or if the flame should cease due to lack of oil ; a device actuated by steam boiler pressure to shut off the burner when the pressure reaches some pre determined value; a device on the boiler to shut off the burner if the water level acts too low for safety or one which automatically feeds additional water to the boiler; a device on warm air furnaces to shut off the burner if the air temperature gets too high; a valve in the oil supply line which automatically closes in the event of fire in or near the cellar; and a device to keep the temperature of the boiler water within certain limits when it is being used to heat domestic hot water. GAS-FIRED APPLIANCES The increased use of gas for house heating purposes has resulted in the production of such a large number of different types of gas heating systems and appliances that today there is probably a greater variety of them than there is for any other kind of fuel. . Gas-fired heating systems may be classified as follows: I. Gas-Designed Heating Systems. A. Central Heating Plants. 1. Steam, hot water, and vapor boilers. 2. Warm air furnaces. B. Unit Heating Systems. 1. Warm air floor furnaces. 2. Industrial unit heaters. 3. Space heaters. 4. Garage heaters. II. Conversion Heating Systems. A. Central Heating Plants. 1. Steam, hot water and vapor boilers. 2. Warm air basement furnaces. 217 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 These systems are supplied with either automatic or manual control. Central heating plants, for example, whether gas designed or conversion systems, may be equipped with room temperature control, push-button control, or manual control. Gas-Fired Boilers and Furnaces Information on gas-fired boilers will be found in Chapter 13. Either snap action or throttling control is_ available for gas boiler operation. This is especially advantageous in straight steam systems because steam pressures can be maintained at desired points, while at the same time complete cut-off of gas is possible when the thermostat calls for it. Warm air furnaces are variously constructed of cast-iron, sheet metal and combinations of the two materials. If sheet metal is used, it must be of such a character that it will have the maximum resistance to the corrosive effect of the products of combustion. With some varieties of manufactured gases, this effect is quite pronounced. Warm air furnaces are obtainable in sizes from those sufficient to heat the largest residence down to sizes applicable to a single room. The practice of installing a number of separate furnaces to heat individual rooms is peculiar to mild climates. Small furnaces, frequently controlled by electrical valves actuated by push-buttons in the room above, are often installed to heat rooms where heat may be desired for an hour or so each day. These furnaces are used also for heating groups of rooms in larger residences. : In a system of this type each furnace should supply a group of rooms in which the heating requirements for each room in the group are similar. The same fundamental principle of design that is followed in the con struction of boilers, that is, breaking the hot gas into fine streams so that all particles are brought as close as possible to the heating surface, is equally applicable to the design of warm air furnaces. Codes for proportioning warm air heating plants, such as that formu lated by the National Warm Air Heating and Air Conditioning Association are equally applicable to gas furnaces and coal furnaces. Recirculation should always be practiced with gas-fired warm air furnaces. It not only aids in heating, but is essential to economy. Where fans are used in con nection with warm air furnaces for residence heating, it is well to have the control of the fan and of the gas so coordinated that there will be sufficient delay between the turning on of the gas and the starting of the fan to prevent blasts of cold air being blown into the heated rooms. An additional thermostat in the air duct easily may be arranged to accomplish this. Warm air floor furnaces are well adapted for heating first floors, or where heat is required in only one or two rooms. A number may be used to provide heat for the entire building where all rooms are on the ground floor, thus giving the heating system flexibility as any number of rooms may be heated without heating the others. With the usual type the register is installed in the floor, the heating element and gas piping being suspended below. Air is taken downward between the two sheets of the double casing and discharged upward over the heating surfaces and into the room. The appliance is controlled from the room to be heated by means of a control lever located near the edge of the register. The handle of the control is removable as a precaution against accidental turning on or off of the gas to the furnace. 218 CHAPTER II. AUTOMATIC FLLEL BURNING EQUIPMENT Space Heaters Space heaters are generally used for auxiliary heating, but may be, and are in many cases, installed for furnishing heat to entire buildings. With the exception of wall heaters, they are portable, and can be easily removed and stored during the summer season. Although they should be connected with solid piping it is sometimes desirable to connect them with flexible gas tubing in which case a gas-shut-off on the heater is not permitted, and only A.G.A. approved tubing should be used. Parlor furnaces or circulators are usually constructed to resemble a cabinet radio. They heat the room entirely by convection, i.e., the cold air of the room is drawn in near the base and passes up inside the jacket around a drum or heating section, and out of the heater at or near the top. These heaters cause a continuous circulation of the air in the room during the time they are in operation. The burner or burners are located in the base at the bottom of an enclosed combustion chamber. The products of combustion pass up around baffles within the heating element or drum, and out the flue at the back near the top. They are well adapted not only for residence room heating but also for stores and offices. Radiant heaters give off considerable portion of their heat in the form of radiant energy emitted by an incandescent refractory that is heated by a Bunsen flame. . They are made in numerous shapes and designs and in sizes ranging from two to fourteen or more radiants. Some have sheetiron bodies finished in enamel or brass while others have cast-iron or brass frames with heavy fire-clay bodies. An atmospheric burner is supported near the center of the base, usually by set screws at each end. Others have a group of small atmospheric burners supported on a manifold attached to the base. Most radiant heaters are supported on legs and are portable; however, there are also types which are encased in a jacket which fits into the wall with a grilled front, similar to a wall register. Gas-fired steam and hot water radiators are popular types of room heating appliances. They provide a form of heating apparatus for intermittently heated spaces such as stores, small churches and some types of offices and apartments. They are made in a large variety of shapes and sizes and are similar in appearance to the ordinary steam or hot water radiator con nected to a basement boiler. A separate combustion chamber is provided in the base of each radiator and is usually fitted with a one-piece burner. They may be secured in either the vented or unvented types, and with steam pressure, thermostatic or room temperature controls. Warm air radiators are similar in appearance to the steam or hot water radiators. They are usually constructed of pressed steel or sheet metal hollow sections. The hot products of combustion circulate through the sections and are discharged from a flue or into the room, depending upon whether the radiator is of the vented or unvented type. Garage heaters are usually similar in construction to the cabinet circulator space heaters, except that safety screens are provided oyer all openings into the combustion chamber to prevent any possibility of explosion from gasoline fumes or other gases which might be ignited by an open flame. They are usually provided with automatic room tem perature controls and are well suited for heating either residence or commercial garages. 219 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Conversion Burners . Residence heating with gas through the use of conversion burners in stalled in coal-designed boilers and furnaces represents a common type of gas-fired house heating system. In many conversion, burners radiants or refractories are employed to convert some of the energy in the gas to radiant heat. Others are of the blast type, operating without refractories. Many conversion units are equipped with sheet metal secondary air ducts which are inserted through the ashpit door. The duct is equipped with automatic air controls which open when the burners are operating and close when the gas supply is turned off. This prevents a large part of the circulation of cold air through the combustion space of the ap pliance when not in operation. With this duct the air necessary for proper combustion is supplied directly to the burner, thereby making it possible to reduce the excess air passing through the combustion chamber. Conversion units are made in many sizes both round and rectangular to fit different types and makes of boilers and furnaces. They may be secured with manual, push-button, or room temperature control. Combustion Process and Adjustments Because of the varying composition of gases used for domestic heating it is difficult to generalize on the subject of gas burner combustion. Little difficulty should be experienced in maintaining efficient com bustion conditions when burning gas. The fuel supply is normally held to close limits of variation in pressure and calorific value and, therefore, the rate of heat supply is nominally constant. Since the force necessary to introduce the fuel into the combustion chamber is an inherent factor of the fuel, no draft by the chimney is required for this purpose. The use of a draft diverter insures the maintenance of constant low draft condition in the combustion chamber with a resultant stability of air supply. A draft diverter is also helpful in controlling the amount of excess air and pre: venting back drafts which might extinguish the flame. (See Chapter 9). Measurement of the Efficiency of Combustion It is possible to determine the results of combustion by analyzing the gases of combustion with an Orsat apparatus. It is desirable to determine the percentage of carbon dioxide (C02), oxygen (02) and carbon monoxide (CO) in the flue gases. While ultimate C02 values of 10 to 12 per cent may be obtained from the combustion of gases commonly used for domestic heating, a combustion adjustment which will show from 8 to 10 per cent COt represents a practical value. Under normal conditions no CO will be produced by a gas-fired boiler or furnace. Limitations as to output rating 'by the A.G.A. are based upon operation with not more than 0.04 per cent CO in the products of combustion. This is too small an amount to be determined by the ordinary flue gas analyzer. Controls Gas burner controls may be divided into two parts: (a) devices to regulate burner operation so that the desired house heating results may be obtained, and (6) devices for the safety of the boiler and burner.' Control devices are treated in detail in Chapter 38. A room thermostat may be used as a control of house heating effect. These may be obtained in a 220 CHAPTER 11. AUTOMATIC FUEL BURNING EQUIPMENT number of types. Some central heating plants are equipped with push- button.or manual control. Class (b) controls include a device to shut off the burner if the gas fails to ignite, a device actuated by boiler pressure, water temperature, or furnace bonnet temperature to shut off the burner when the pressure or temperature becomes excessive, a device on the boiler to shut off the.burner if the water level falls below safe limits or one which automatically feeds additional water to the boiler, and a device for controlling the gas pressure, within desired limits. The main gas valve may be either of the snap action or throttling type. :. Sizing Cas-Fired Heating Plants . While gas-burning equipment can be and usually is so installed as to be completely automatic, maintaining the temperature of rooms at a pre determined and set figure, there are in use installations which are manually controlled. Experience has shown, that, in order to effectively overcome the starting load and losses in piping, a manually-controlled gas boiler should have an output as much as 100 per cent greater than the equiva lent standard cast-iron column radiation which it is expected to serve. Boilers under thermostatic control, however, are not subject to such severe pick-up or starting loads. Consequently, it is possible to use a much lower selection, or safety factor. A gas-fired boiler under thermo static control is sensitive to variations in room temperatures so that in most cases a factor of 20 per cent is sufficient for pick-up load. The factor to be allowed for loss of heat from piping, however, must vary somewhat, the proportionate amount of piping installed being con siderably.greater for small installations than for large ones. Consequently a selection factor for thermostatically controlled boilers must be variable. Liberal selection factors to be added to the installed steam radiation under thermostatic control are given in Fig. 1 of Chapter 13. . Appliances used for heating with gas should bear the approval, seal of the American Gas Association Testing Laboratory. Installations should be made in accordance with the recommendations shown in the publi cations of that associatiorf. Ratings for Gas Appliances ' Since a gas appliance has a heat-generating capacity that can be. pre dicted accurately to within 1 or 2 per cent, and since this capacity is not affected by such things as condition of fuel bed and soot accumulation, makers of these appliances have an opportunity to rate their product in exact terms. Consequently all makers give their product an hourly Btu output rating. This is the amount of heat that is available at the outlet of a boiler in the form of steam or hot water, or at the bonnet of the furnace in the form of warm air. The output rating is in turn based upon the Btu input rating which has been approved by the American Gas Asso ciation Testing .Laboratory and upon an average efficiency which has been assigned by that association. . In the case of boilers, the rating can be put in terms of square feet of equivalent direct radiation by dividing it by 240 for steam, and 150 for water. This gives what is called the American Gas Association rating, and is the manner in which all appliances approved, by the American Gas Association Laboratory are rated. To use these ratings it is only necessary 221 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 to increase the calculated heat loss or the equivalent direct radiation load by an appropriate amount for starting and piping, and to select the boiler or furnace with the proper rating. The rating given by the American Gas Association Laboratory is not only a conservative rating when considered from the standpoint of capacity and efficiency, but is also a safe rating when considered from the standpoint of physical safety to the owner or caretaker. The rating that is placed upon an appliance is limited by the amount of gas that can be burned without the production of harmful amounts of carbon monoxide. Gas boilers are available with ratings up to 14,000 sq ft of steam, while furnaces with ratings up to about 500,000 Btu per hour are available. REFERENCES Stoker Information, Bulletin No. 5, Committee of Ten, 307 N. Michigan Ave., Chicago, 111. Domestic Burners for Pennsylvania Anthracite, Commercial Standard CS48-34, U. S. Department of Commerce. Performance Expectancy of Domestic Underfeed Stokers for Anthracite, by Allen J Johnson (Transactions, A.I.M.E., Coal Division, Vol. 119, 1936). The Relation of the Size of Bituminous Coals to Their Performance on Small Under feed Stokers--The Relation of the Size in the Hopper to That Burned in the Retort, by R. A. Sherman and E. R. Kaiser, Technical Report No. 1, Bituminous Coal Research, Inc., (December, 1935) Pt. I. The Relation of the Size of Bituminous Coals to Their Performance on Small Under feed Stokers--Burning Tests on Four Typical Coals, by R. A. Sherman, E R. Kaiser and H. R. Limbacher, Technical Report No. 1, Bituminous Coal Research, Inc. (July, 1937) Pt. II. .. Stoker Coals, Anonymous, Bulletin of Chesapeake and Ohio Railway Co., 1935. A.S.H.V.E. Research Report No. 907--Study of Performance Characteristics of Oil Burners and Low Pressure Heating Boilers, by L. E. Seeley and E. J. Tavanlar (A.S.H.V.E. Transactions, Vol. 37, 1931, p. 517). A.S.H.V.E. Research Report No. 925--A Study of Intermittent Operation of Oil Burners, by L. E. Seeley and J. Hi' Powers (A.S.H.V.E. Transactions, Vol. 38, 1932, P- 317). Air Supply and Its Effect on Performance of Oil Burners and Heating Boilers, by L. E. Seeley, J. H. Powers and E. J. Tavanlar (A.S.H.V.E. Transactions, Vol. 39, 1933, p- 75). .. .. Study of Fuel Burning Rates and Power Requirements of Oil Burners, in Relation to Excess Air, by L. E. Seeley and E. J. Tavanlar (A.S.H.V.E. Transactions, Vot.. 40, 1934, p. 319). Oil" Burning, in Residences, by D. W. Nelson (A.S.H.V.E. Transactions, Vol. 41, 1935, p. 355). . Domestic Oil Burners, by A. H. Senner (Mechanical Engineering, November, 1936). A Study of Oil-Fired Heating Boilers, by R. C. Cross and W. R. Lyman (Heating and Ventilating, October, 1931). . Value of Oil Burner Installation Surveys, by R. C. Cross and W. R. Lyman (Heating and Ventilating, January, 1931). Comfort Heating, American Gas Association. . Approval Requirements of Central House Heating Gas Appliances, American Gas Association. A Method for Determining Fuel Burning Rates in Heating Boilers Fired by Auto matic Devices, by R, C. Cross (Heating and Ventilating, January, 1932). Heat Losses and Efficiencies of Fuels in Residential Heating, by R. A. Sherman and R. C. Cross (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 185). Efficiencies and Costs of Various Fuels in Domestic Heating, by R. A. Sherman and R. C. Cross, Technical Report No. 3, Bituminous Coal Research, Inc., (December, 1936). Automatic Heating Equipment, American Architect.Reference Data, No. 7, September, 1933. 222 Chapter 12 HEAT AND FUEL UTILIZATION Fuel Consumption Records, Calculated Heat Loss Estimation Method, Maximum Rate of Fuel Burning, Degree-Day Method, ~ Unit Fuel Consumption per Degree-Day, Maximum Demands and Load Factors MANY methods are in use for estimating in advance of actual oper ation the anticipated heat or fuel consumption of heating plants over long or short periods. With suitable modification in procedure these same general methods are frequently useful in checking the degree of effectiveness with which heat or fuel is utilized during plant operation. In applying any of these estimating methods to the consumption of a particular building plant it should be noted that (a) reliable records of past heat or fuel consumptions of this building will usually produce more trustworthy estimates of future consumptions than will any data obtained by averages or from other similar buildings; (b) where no past records exist useful data can sometimes be obtained from records of similar buildings with similar plants in the same locality; (c) records of consump tion which are averages from many types of plants in many types of buildings in various localities, can produce no better than an average estimate which may be far from accurate; (d) estimates based on com puted heat losses without the benefit of operating data are wholly de pendent on how well the computation represents the actual facts. Where records of past consumptions are available they should be examined for reliability to be sure that the records show fuel or heat for the heating plant only, or else make a suitable allowance for fuel used for other purposes, such as heating service water. Weights and measures shown on invoices may not always agree with fuel used, for residues left in bins or tanks may represent a considerable fraction of the fuel charged to a building. Generally, plant operating records of fuel used are to be preferred to those obtained from accounting or bookkeeping offices from fuel invoices. Records from similar buildings even in the same locality should be examined with care before being used as the basis of estimates. The type of heating system, the quality of supervision in manual plants, the kind of control in automatic plants, and the attention given to the plant operation are all factors in fixing the consumption in any building. Many times these factors do not show up in superficial examination and are even difficult to evaluate when known to be present. Especially check the 223 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 records to be sure that they do not include energy or fuel used for other purposes than heating the building. Estimates based on computed heat losses alone are frequently the only ones possible to obtain especially where new equipment is put into unusual buildings and there is a scarcity of records and an absence of .experience data. Such estimates also have to be made where direct information is not obtainable as, for example, if a survey is being made without the assistance or knowledge of the building operator and thus without information as to the actual consumption. Estimates of this kind are also useful in some cases where a relative standard of performance is desired to serve as a base of comparisons in a campaign of fuel utili zation. In such situations it can be plausibly argued that an estimate based on computed heat quantities is to be preferred to one which is related to operating methods. In interpreting and evaluating heat or fuel consumption estimates as well as in their preparation, it is well to realize that any estimating method used will produce a more reliable result over a long period operation than over a short period. Nearly all of the methods in common use will give trustworthy results over a full annual heating season, and in some cases such estimates will prove consistent within themselves for monthly periods. As the period of the estimate is shortened there is more chance that some factor not allowed for in the estimating method will become controlling and thus give discrepant and even ridiculous results. Of the various estimating methods in use attention is directed in this discussion to but two as they are illustrative of all, viz: (1) calculated heat loss method, and (2) degree-day method. CALCULATED HEAT LOSS METHOD This method is theoretical and assumes constant temperatures for very definite hours each day throughout the entire heating season. It does not take into account factors which are difficult to evaluate such as opening of windows, abnormal heating of the building, sun effect, poor heating systems, and many others. ' In order to apply this method the hourly heat loss from the building under maximum load, or design condition is computed following the principles discussed in Chapters 5 and 6 and the method described .and illustrated in Chapter 7. In some cases, however, depending on the presence of interior par titions, the computed heat loss is modified when used for estimating the heat or fuel consumption. If the building has no interior walls or par titions then, by the method of Chapters 6 and 7, the infiltration losses are calculated by using only half the total window crack. In such a building the calculated loss need not be modified in order to prepare heat or fuel estimates by this method. Where the building does contain interior walls or partitions instead of using as the calculated heat loss (H) which is equal to the sum of the transmission losses (Ht) and the infiltration H' losses (Hi), it is more desirable to let H = Ht + -- 224 CHAPTER 12. HEAT AND FUEL UTILIZATION In predicting fuel consumption for building heating by the Calculated Heat Loss Method, the general formula is: H(t- Q N E (td -- to) C U) where F = quantity of fuel or energy required (in the units in which C is expressed): H = calculated heat loss, Btu per hour, during the design hour, based on to and tj (generally H = Ht + H\ but may on occasion equal Ht H--J. t -- average inside temperature maintained overestimate period, degrees Fahrenheit. to = average outside temperature through estimate period, degrees Fahrenheit (Table 2, Chapter 7). . Id = inside design temperature, degrees Fahrenheit (usually 70 F). to = outside design temperature, degrees Fahrenheit (see Outside Temperatures, Chapter 7). I . If -- number of heating hours in estimate period (for an Oct. 1--May 1 heating season, 5088). . E = efficiency of utilization of the fuel over the period, expressed as a decimal; not the efficiency at peak or rated load condition. C -- heating value of one unit of fuel or energy. Example 1. A residence in Philadelphia is to be heated to 70 F from 6 a.m. to 10 f.m. and 55 F from 10 p.M. to 6 a.m. The calculated hourly heat loss is 120,000 Btu per hour based on 70 F inside at --5 F outside. If the building is to be heated by metered steam, how many pounds would be required during an average heating season? . Solution. The heating value of steam may be taken at 1000 Btu per pound, and since it is purchased steam, the efficiency can be assumed as 100 per cent. From Table 2, Chapter 7, /a = 42.7'F. The average inside temperature is: (16 X 70) + (8 X 55) _ Substituting in Equation 1: 120,000 (65 - 42.7) 5088 1.00 [70 - (-5)].1000 181,239 lb. Example S. How much would the fuel cost to heat the building in Example 1 during an average heating season with coal at S8 per ton and with a calorific value of 11,000 Btu per pound, assuming that the seasonal efficiency of the plant was 55'per cent? Solution. Substituting in Equation 1: F = (igflS = 3'13 'b = 15 ton, which, at 88 per ton, costs 8120.' .. Example 3. What will be the estimated fuel cost per year of heating a building with . gas, assuming that the calculated hourly heat loss is 92,000 Btu based on 0 F, which/ includes 26,000 Btu for infiltration? The design temperatures are 0 F and 72 F. The normal heating season is 210 days, and the average outside temperature during the heating season is 36.4 F. The seasonal efficiency will be 75 per cent. The heating plant will be thermostatically controlled, and a temperature of 55 F will be maintained from 11 P.M. to 7 a.m. Assume that the price of gas is 7 cents per 100,000 Btu of fuel con sumption, and disregard the loss of heat through open windows and doors. Solution. The average hourly temperature is: ^ ^gg-X16)^+_(55 X 8) = 663F . 225 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 The maximum hourly'heat loss will be: H = 92,000 - 26,000 = 79,000 Btu. M = 79,000 (66.3 - 36.4) X 24 X 210 100,000 X 0.75 X (72 - 0) = 2204.6 hundred thousand Btu. 2204.6 X $0.07 = $154.34 = estimated fuel cost per year of heating building. Equation 1 can be expressed as: F = -2- V (`~^N . EC - (Id - t0) (2) CHAPTER 1Z HEAT AND FUEL UTILIZATION In the case of gravity warm air heating installations, the load is usually expressed in square inches of leader pipe. This can be converted into hourly heat loss by multiplying by the factors in Table 1. Example 4- A building located in Salt Lake City with an oil-burning heating plant has a calculated hourly heat loss of 260,000 Btu per hour. The plant is designed to maintain a temperature of 70 F inside during all 24 hours of the day, the outside design temperature is --5 F, the average outside temperature 40 F, the heating season 5088 hours long, the assumed efficiency 60 per cent, and the oil has a calorific value of 143,400 Btu per gallon. What will be the seasonal fuel consumption? Solution. Enter Fig. 2 at 260,000 on the upper horizontal scale, move vertically to the 60 per cent efficiency curve, and horizontally to the vertical scale where the firing rate is found as 3.0 gal per hour. 1--------1------- 1 i-------r----j------- 1-------- 1------- 1------ 1-- i---------1-------- 1--------1--------1 "i '' o 4 6.8 10 12 14-16 >8 20 GROSS OUTPUT - HUNDRED FEET STEAM RADIATION -1--I--I--I--l--I--I--l--I--l--I--I--l--i--l--1--'-->--I--i--r--1--I--I--I--l--r- o 5 10 IS 20 25 30 GROSS OUTPUT HUN0RED FEET WATER RADIATION Fig. 1. Coal Fuel Burning Rate Chart where the expression H' is the rate at which fuel is burned during the iLL, design hour. Values of this rate are plotted as ordinates in Figs. 1, 2 4nd 3 for coal, oil and gas. For a given efficiency, the rate of fuel burning is directly proportional to the load and therefore these charts can be ex tended by moving the decimal points the same number of digits in both vertical and horizontal scales. Use of these charts thus expedites the estimate. ; The charts are plotted so that the load is expressed in three terms: (a) hourly heat loss at design conditions, (b) square feet of steam radiator surface (240 Btu per hour), and (c) square feet of hot water radiator surface (150 Btu per hour). By entering the chart at the correct point on the abcissa corresponding to the calculated heat loss (H), following ver tically to the seasonal efficiency assumed and thence horizontally to the fuel rate, the rate of fuel burning during a maximum or design hour will be found along the left hand scale for various calorific values of the fuel. 226 I-------1-----------1-------- 1----------1------- 1----------1------- 1---------- 1-...I-----------1--------1---------- 1------- 1-----------1-------- 1---------- 1------- 1---------- 1------- 1-----------T" 0 2 4 6 8 10 12 14 16 20 GROSS OUTPUT * HUNDRE0 FEET STEAM RA01ATI0N i--i 0 i--i i i i i i i i1' i -- i i i i i--i i i i mi --i--i--i--i--r-~i--i--i--i--i--r" 5 10 15 20 25 50 GROSS OUTPUT-HUNDRED FEET WATER RADIATION Fig. 2. Oil Fuel Burning Rate Chart This chart is based upon No. 3 oil having a heat content of 143.400 Btu per gallon. If other grades of oil are used multiply the value obtained from this chart by the following factors: No. 1 oil (139.000 Btu per gallon) 1.032; No. 2 oil (141,00<XBtu per gallon) 1.017; No. 4 oil (144,500 Btu per gallon) 0.992; No. 5 oil (146.000 Btu per gallon) 0.982; and No. 6 oil (150,000 Btu per gallon) 0.956. Substituting this in Equation 2 for n. _ O n v, (70 - 40) 5088 F - 3 0 x --0 -7^5) 6106 gal. Example 6. What would be the total gas consumption over a full heating season of a gas-fired gravity warm air furnace designed according to the Code1, and with four 12 in. and two 8 in. round leaders to the first floor and six 10 in. leaders to the second floor, if the gas has a heating value of 500 Btu per cubic foot, the plant operates at a 70 per cent . 'Standard Code Regulating the Installation of Gravity Warm Air Heating Systems in Residences (9th edition), and the Technical Code for the Design and Installation of Mechanical Warm Air Heating Systems, may be obtained from the National Warm Air Heating and Air Conditioning Association, 5 E. Long St., Columbus. Ohio. . 227 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 seasonal efficiency and is designed to maintain an average inside temperature of 65 F when it is 10 F outside in a city where the average outside temperature is 45 F and the heating season is 5088 hours long? Solution. The area of the round leaders is: 12 in., 113 sq in.; 10 in., 79 sq in.; and 8 in., 50 sq in. From Table 1 the total Btu transmitted is: First Floor: [(4 X 113) + (2 X 50)] X 111 = 61,272 Btu per hour. Second Floor: (6 X 79) X 167 = 79,158 Btu per hour. . Total 140,430 Btu per hour. Allowing 10 per cent for duct and furnace losses, the gross output would be 154,500 Btu per hour. . GROSS CALORIFIC VALUE CROSS OUTPUT - HONORED FEET STEAM RADIATION I-----1 | t | | ) | I I I |---- 1-----1 I I I I I I I-----1----------I-----1--T-----T-T I I I-- o 5 10 20-25 SO GROSS OUTPUT- HUNDRED FEET WATER RADIATION Fig. 3. Gas Fuel Burning. Rate Chart Enter Fig. 3 at 154.5 on the upper horizontal scale, move to the 70 per cent efficiency curve and thence to the 500 Btu per cubic foot vertical scale and find ^ ^ to bq ap proximately 440 cu ft per hour. . Substituting in Equation 2: F = 440 X (65 - 45) 5088 (70 - 10) = 746,428 cu ft.! . Maximum Rate of Fuel Burning The rate at which fuel is burned during the maximum, or design hour is frequently useful in setting, or adjusting, the fuel feed devices attached to K#c)stokers, oil-burners, and gds burners. This rate and can be found from the charts of Figs. 1, 2 and 3 in the same way as outlined in the Examples 4 and 5. In using the charts for this purpose, however, it should be noted that the efficiency (E) is the overall efficiency of the boiler 228 CHAPTER 12. HEAT AND FUEL UTILIZATION or furnace at the time of peak load. This efficiency is generally consider ably greater than the value selected for E when the seasonal efficiency of utilization is used in making seasonal fuel estimates. Failure to dis tinguish between the two essentially different meanings attached to E may result in grossly inaccurate estimates. The correct fuel burning rate can be determined directly from the several charts for oil or gas burning installations, as these customarily operate on a strictly intermittent basis. These fuel burning devices usually introduce the fuel at a single fixed rate during the on periods and this rate should be sufficient to carry the gross or' maximum design load. In the case of coal stokers, which are usually capable of variable rates of firing, it is desirable to operate at as low a rate as weather conditions will permit, but the maximum firing rate of the stoker should be sufficient to carry the gross load. This rate may be determined by the same method as used for oil or gas. Table 1. Heat Carrying Capacity of Gravity Warm Air Furance Round Leader Pipes '. 180 F Register Temperature Leader Pipe Third floor................................................................... HBtu per r at Desion Conditions per Sq In. or Leader Pipe in 167 200 Example 6. The estimated net load (including domestic hot water supply) as calcu lated for a residence is 1500 sq ft of hot water radiation. Determine the firing rates for various mechanically fired fuels assuming an overall boiler efficiency of 70 per cent; using coal with a calorific value of 12,500 Btu per pound; No. 3 fuel oil and natural gas having a gross heating value of 1000 Btu per cubic foot. . _ Solution. Referring to Fig. 1, Chapter 13, a piping and pick-up factor for a net load of 1500 sq ft is found to be 43 per cent or the gross output is equivalent to 1500 X 1.43 = 2145 sq ft of hot water radiation. Using the charts in Figs. 1, 2 and 3 project vertically from the gross output value on the proper horizontal scale to the intersection of the 70 per cent efficiency line. From the intersection of this line proceed horizontally to the proper vertical scale where a direct value of the required fuel burning rate is given. These values are rates of burning while firing device is in operation and are not indicative of hourly fuel consumption. By use of the respective charts the firing rates for the various fuels will be found to be: coal 36.8 lb per hour, oil 3.2 gal per hour, and gas 460 cu ft per hour. DEGREE-DAY METHOD This method is based on consumption data which have been taken from buildings in operation, and the results computed on a degree-day basis. While this method may not be as theoretically correct as the Calculated Heat Loss Method, it is of more value for practical use. The amount of heat required by a building depends upon the outdoor temperature, if other variables are eliminated. Theoretically it is pro portional to the difference between the outdoor and indoor temperatures. Some years ago the American Gas Association2 determined from experi- See Industrial Gas Series. House Heating, (third edition) published by the American Gas Association. 229 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 ment in the heating of residences that the gas consumption varied directly as the difference between 65 F and the outside temperature. In other words, on a day when the temperature was 20 deg below 65 F, twice as much gas was consumed as on a day when the temperature was 10 deg below 65 F. The degree-day is defined in Chapter 46. Some years ago the National District Heating Association studied the metered steam consumption of 163 buildings3 in 22 different cities and published data substantiating the fact that the 65 F base originally chosen by the gas industry is approximately correct. (See Table 2.) If the degree-days occurring each day are totaled for a reasonably long period, the fuel consumption during that period as compared with another period will be in direct proportion to the number of degree-days in the two periods. Consequently, for a given installation, the fuel consumption can be calculated in terms of fuel used per degree-day for any sufficiently long period and compared with similar ratios for other periods to deter mine the relative operating efficiencies with the outside temperature variable eliminated. . Predictions of fuel consumption are generally based on the average number of degree-days which have occurred over a long period of years, and such averages, by months, on a 65 F base, are given by months and heating season totals, for various United States and Canadian cities in Table 3. In general, attempts to apply the degree-day method to fuel consumptions over a period of less than a month are of questionable value. Formula for Degree-Day Method The general formula for predicting fuel consumption by the DegreeDay Method is: where F= UXNXD (3) F -- fuel consumption for the estimate period. U = unit fuel consumption, or quantity of fuel used per degree-day per building load unit. ------ N = number of building load units. D = number of degree-days for the estimate period. Values of D for use in Equation 3 are given in Table 3. Values of N depend bn the particular building for which the estimate is being pre pared and must be found by surveying plans, by observation, or by measurement of the building. Values of U for use in this equation are the Unit Fuel Consumptions per Degree-Day and are obtained as a result of the collection of operating information. Certain of this information is presented later but before referring to these data attention is directed to the nature of the unit. Unit Fuel Consumptions per Degree-Day The quantity of fuel used per degree-day in a given heating plant can be reduced to a unit basis in terms of. quantity of fuel (or steam) per degree-day per square foot of radiator, per cubic foot of heated building space, or per thousand Btu hourly heat loss at design conditions. A less frequently used basis is quantity of fuel- per degree-day per square foot of* *These buildings are all served with steam from a district heating company. 230 . . . CHAPTER 12. HEAT AND FUEL UTILIZATION air flow area. In fact any convenient unit can be used to relate the con sumption to the degree-day and to the building. The choice of these units requires explanation and some discrimination and judgment. The use of heated space in preference to the gross building cubage used by architects is obviously more accurate for this purpose. The architects' cubage includes the outer walls and certain percentages of attic and basement space which are usually unheated. The net heated space is usually about 80 per cent of the gross cubage and can be calcu lated from the latter if it cannot be measured. The cubical content is somewhat inaccurate as a basis of comparison due to differences in types of construction, exposure, and ratio of exposed area to cubical contents. Use of equivalent radiator surface figures is fundamentally the same as Table 2. Base Temperature for the Degree-Day Ttfb or Building Office--......................................................................................... Office and Bank. ...........--..................................... ......... Bank----------- ----- ---------- -..................................... ......... Office and Telephone Exchange.................................. Office and Stores........... .......... .. ............................... Stores..................... ..................................................................... Department Stores.............................................................. Hotels..... ................ ................................................................ Apartments.-- ............................................... : Residences................................. ............................................ Clubs............... .............................................. ............................. Lodges.. ________________ __________________________ Theatres.TM..................... ........................................ ................ Churches. ______ -............................................................. Garages. . ------------------------------------------------------- -------- Auto Sales and Service. ________ __________ . Newspaper and Printing.................. ............................. Warehouse and Loft- ___________ __________ ___ Office and Loft........ ................ .-........................................... Manufacturing.. _ .............................................. No. or Buildings Ajultzed 60 4 3 2 6. 11 12 7 14 8, 4 5 3 2 2 4 3 3 2 8 Temperature F Cor responds to Zero Steam Consumption 66.2 65.8 66.2 65.5 67.4 64.0 64.3 . 66.5 68.8 66.9 65.5 64.9 67.6 65.8 64.8 61.2 67.7 67.7 65.2 65.4 > Average for 163 Buildings .. . __ 66.0 F Report of Commercial Relations Committee, Proceedings, Notional District Heating Association. 1932. using a calculated heat loss and therefore units in terms of fuel per degree- day per equivalent square foot of calculated radiator surface, per 1000 Btu of calculated heat loss, or per Btu of heat loss at design conditions are all of equal accuracy and desirability. It is doubtful if installed radiator surface as determined by count should be used at all. Radiator units are also of questionable value where there is fan coil surface or warm air systems. In view of all these considerations it is believed that the unit based on thousands of Btu of hourly calcidated heat loss for the design hour is probably the most desirable although the one most widely used seems to be units of fuel {or heat) per degree-day per square foot of equivalent direct radiator surface. . Since this unit is the one most widely used at present the unit fuel con sumptions given in succeeding paragraphs of this chapter make use of this unit to a considerable extent, although it should be understood that most of these units of consumption can be transposed as desired. 231 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Table 3. Degree-Days for Cities in the United States and Canada* Stats Cnr Jan. Apr. Mat Jong Jolt Aug. Sept. Oct. Total Birmingham- 589 521 260 69 318 595 2352 Mobile....... ...... 428 311 152 186 394 1471 Flagstaff.__:..... 1153 969 654 465 171 . 40 252 577 840 1128 7145 Tucson..'......... i. 459 325 87 252 465 1845 Ark.:_ Little Rock..... 719 582 Calif- Los Angeles..... 326 266 San Francisco. 465 356 78 47 381 651 2811 159 90 123 301 1504 294 264 195 202 186 114 146 261 428 3264 Colo.. Colo. Springs... 1085 991 612 369 90 162 502 789 1066 6518 Denver.__-- 1079 918 534 267 72 428 759 1017 5874 Conn. New Haven...:. 1110 1011 543 223 39 360 693 1017 5895. D. C.- Washington....: Fla... Jacksonville-- Ga.._ Atlanta..--........ .Savannah--...... 970 . 848 285 207 682 557 409 316 348 25 132 251 594 896 4626 75 267 890 96 396 639 2890 201 397 1490 Idaho Boise--......-...... 1097 848 435 236 102 434 738 1011 5552 Bl Chicago---------- 1262 1095 549 248 3 353 756 1113 6290 Springfield....... 1181 1008 ) 366 56 282 681 1039 5373 ind Evansville....... 949 854 ) 276 Indianapolis..... 1128 969 384 59 155 528 862 4244 298 687 1017 5298 Iowa.. Des Moines..... 1392 1173 441 118 357 798 1215 6384 Sioux City....... 1435 1260 489 164 '33 415 870 1265 6898 Kans. Dodge City..... 1116 890 342 47 <276 672 1104 5035 Topeka--.......... 1221 980 339 270 699 1051 5307 Ky Lexington------ : 973 868 l 342 25 Louisville......... 939 801 ) 264 245 612 905 4618 186 552 849 4180 La... Me. New Orleans... 332 230 Eastport--........ 1380 1232 Portland--...... 1321 1168 ) 102 301 1024 786 543 300 143 136 276 543 843 1228 8520 r 642 329 39 120 443 780 1153 7012 Md Baltimore--...... 955 843 348 22 223 567 874 4533 Mass Boston.............. 1150 1042 i 570 245 48 363 693 1026 6045 M ich Detroit.............. 1252 1134 Marquette....... 1500 1361 573 226 804 496 186 42 400 777 1113 6490 43 225 567 960 1302 8693 Minn. Duluth.............. 1727 1473 810 524 198 37 261 620 1062 1491 9480 Minneapolis-- 1609 1400 570 236 93 481 963 1404 7850 Miss... Vicksburg..--.... 521 384 Mo. Kansas City..--; 1094 958 St. Louis____ 1060 854 5 303 12 J 276 252 471 1823 214 612 983 4852 205 597 936 4585 Mont. Billings--........ 1318 1120 5 534 316 60 189 524 909 1194 7119 Nebr- Nev... N. HN. J.. Havre--.......... Lincoln--........ Omaha...... -- Reno............... Concord......... Atlantic City Trenton......... 1624 1450 1311 1131 1355 1126 1042 823 1349 1240 992 904 1014 941 ) 630 369 144 ) 417 99 3 414 84 1 534 366 90 L 669 298 54 3 519 220 5 402 81 270 620 1041 1383 8700 316 753 1132 5999 329 780 1175 6131 144 453 714 973 5892 168 484 846 1234 7353 254 588 893 5176 242 588 930 4933 N.M.. Santa Fe........ N.Y.. Albany........... Buffalo........... New York..... Utica...... ........ N. C... Raleigh--..... Wilmington.. 1110 902 1287 1142 1240 1156 1060 960 1248 1181 722 630 555 468 5 543 298 D 549 183 675 335 7 486 155 9 588 253 5 183 2 108 3 12 120 .459 72 446 75 419 276 182 430 130 19 780 1073 6063 774 1147 6580 774 1104 6822 618 955 5347 781 1144 6796 429 694 3234 303 527 2302 N.D... Bismarck...... 1807 1548 Ohio-- Cincinnati..... 1011 871 Cleveland___ 1181 1075 Columbus-__ 1113 980 Okla.. Oklahoma City 865 742 Ore..... Portland.. 806 644 Salem....... 778 633 3 657 9 339 0 564 8 42C 5 162 8 402 6 42 338 45 19 220 ,, .. 87 245 9C 285 111 222 626 1113 1553 9192 248 615 921 4703 27 366 732 1060 6155 313 690 1017 5398 105 459 , 815 3613 105 332 558 729 4469 102 350 600 747 4618 232 CHAPTER 12. HEAT AND FUEL UTILIZATION Table 3. Degree-Days for Cities in the United States and Canada* (Concluded) State Crrr Jan. Feb. Mae. Apr. Mat June JULT Aug. Sept. Oct. Not. Dec. Total Pa Philadelphia.... 1001 893 756 402 68 1054 944 787 423 78 242 588 905 4855 313 069 967 5235 F l Providence. -- 1116 1070 890 558 251 s. c... Charleston........ 487 372 242 36 63 348 693 1026 6015 207 425 176Q Spartanburg.... 725 622 431 147 121 429 716 3191 q n Sioux Falls-- ... 1547 1358 1045 564 217 93 484 945 1404 7657 Tenn. 744 599 384 96 62 402 663 2950 812 675 477 180 136 483 744 3507 Texas Austin.... ........... 487 330 133 201 434 1585 Dallas................ 617 493 267 9 303 567 2256 Houston...... --. 366 277 65 114 335 1157 San Antonio.... 381 274 74 126 347 1202 Utah.. 1262 1072 893 525 329 48 114 468 819 1218 6748 Salt Lake City 1110 885 722 453 236 18 388 723 1020 5555 Vt....... Burlington--..... 1429 1294 1088 654 273 3 144 481 861 1287 7514 Va___ Fredericksburg 887 820 583 303 223 549 877 4242 Norfolk. __ ..... 738 650 521 246 99 411 685 3350 Richmond........ 825 703 552 240 158 483 766 3727 Wash. Seattle............... 775 652 623 465 319 168 40 43 192 403 570 7i6 4966 1172 952 778 504 285 81 192 515 819 1057 6355 W.Va. Morgantown.... 1026 944 713 414 78 295 648 977 5095 Parkersburg..--. 995 907 679 360 47 Wis.... Fond du Lac.-- 1507 1322 1048 603 276 282 630 1048 4948 117 493 921 1330 7617 Green Bay--..... 1538 1358 1125 600 322 132 . 505 921 1324 7825 LaCrosse........... 1535 1265 1033 528 183 96 462 909 1311 7322 Milwaukee.___ 1383 1201 1023 648 350 39 84 450 846 1221 7245 Wyo... Cheyenne--....... 1215 1075 995 720 446 126 240 605 900 1144 7463 Pro* VINCE Crrr Jan. Feb. Mar. Apr. Mat. June July Aug. Sept. Oct. Not. Dec. Total Alb.... Calgary............ 1674 1428 1240 750 496 270 124 186 450 744 1170 1395 9,927 Edmonton........ 1829 1512 1302 720 434 270 124 186 450 713 1230 1519 10,289 B. C.:. Vancouver. ..... 899 756 713 510 341 180 62 31 270 496 660 837 5,555 Man... Winnipeg--....... 2139 1820 1581 810 465 90 62 270 744 1320 1829 11,130 N. B... Moncton.......... 1519 1428 1178 810 465 210 93 300 620 Q30 1333 8 886 N. S. Halifax...... ....... 1302 1176 1085 780 496 210 210 496 780 1147 7589 Ont__ OttawaL. ......... 1674 1484 1271 690 279 30 210 589 qon 1457 8*676 Port Arthur--.l. 1829 1624 1426 900 558 240 62 86 360 713 1140 1550 10I588 Toronto............ 1333 1204 1209 720 372 60 180 558 870 1209 7 715 P.E.I. Charlottetown 1178 1120 1209 870 529 210 Que-- MontreaL_____ 1581 1428 1209 720 310 600 558 870 1240 8,382 180 558 960 1395 8,341 Sask... Quebec..... ....... 1705 1484 1333 Saskatoon........ 2108 1820 1581 870 810 434 465 120 210 31 62 155 270 450 651 1050 1519 9,467 806 1290 1736 11,493 Unjted States dtira abstracted by permission from Degree-Day Handbook (Second Edition. aJ afford Strock and C. H. B. Hotchkiss. Figures for Canadian cities abstracted from Healing or Ventilating, October. 1939. . Estimating Gas Consumption Values of the Unit Fuel Consumption Constant (Z7) for gas are given in Table 4 for various gas heating values, and different types and sizes of heating plants. They are based on an inside design temperature of 70 F and an outside design temperature of 0 F and apply only to these conditions. For other design conditions corrections must be made as given in Table 5. Estimates for industrial buildings where low inside temperatures are maintained cannot be made from this table. . 233 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 " The factors in Table 4, as corrected if necessary, are satisfactory for regions having 3500 to 6500 degree-days per heating season. In regions with less than 3500 degree-days the unit gas consumption is higher than given; where over 6500, the unit is less than given. Ten per cent addition or deduction in these cases is recommended by AGA publications ' For gas heating values other than those given in Table 4, simply inter polate or extrapolate. It will, also be noted that Table' 4 applies only to small installations. In general the larger the installation the smaller the unit gas consumption becomes and the values in the table should be used with care, if at all, in large gas-burning installations. . Example 7. Make an estimate of the gas required to heat a building located in Chicago, 111., assuming that the calculated heating surface requirements are 1000 sq ft of hot water radiation based on design temperature of 0 F and 70 F. Chicago has 800 Btu mixed gas, and 6290 degree-days. Solution. Using Equation 3 and Table 4, the fuel consumption for a design tem perature of 0 F with 800 Btu gas is found to be 0.085 cu ft of gas per degree-day per square foot of hot water radiation. 0.085 X 1000 X 6290 = 534,650 cu ft. Estimating Oil Consumption Unit fuel consumption factors for oil, similar to those for gas in Table 4 are given in Table 6. The factors in Table 6 apply only to an inside design Table 4. Factors for Estimating Gas Consumption3 Btu Value or Gas per Cu Ft 500 535 800 1000 Hot Water Cu Ft Gas per Degree-Day . per Sq Ft Radiator . Dp to 500 8q Ft 500 to 1200 8q Ft Over 1200 Sq Ft 0.142 0.132 0.089 0.071 : 0.135 0.126 0.085 0.068 0.128 0.120 0.081 0.065 . Steam ' Warm Air Cu Ft Gas per Degree-Day per Sq Ft Radiator Dp to 500 Sq Ft 300 to 700 Sq Ft Over. 700 Sq Ft Cu Ft Gas per Degree-Day per 1000 Btu Hourly Design Heat Loss Gravity Fan Systems 0.242 0.226 0.151 0.121 0.231 0.215 0.144 0.115 0.220 0.206 0.137 0.110 0.855 0.800 0.534 0.428 0.820 0.766 0.513 ; 0.410 1 Therm 100.000 Btu Gas Consumption in Therms per Degree-Day 0.000708 0.000675 0.000642 8 O 0.00115 0.00110 0.00428 0.00409 Abstracted from Comfort Heating, American Gas Association, 1938. Table 5. Correction Factors for Outside Design Temperatures Outbids Design Temp. Deg F -20 -10 0 +10 +20 Inside Design Temp. Deq F 70 70 70 70 70 Multiflt Values in Tables 4,6 and 7 bt 0.778 0.875 0.000 1.167 1.400 CHAPTER 12. HEAT AND FUEL UTILIZATION temperature of 70 F and an outside design temperature of OF. For other outside design temperatures, the constants in Table 6 must be multiplied by the values in Table 5 as explained under Estimating Gas Consumption. Table 6 assumes the use of oil with a heating value of 140,000 Btu per gallon. For other heating values, multiply the values in Table 6 by the ratio of 140,000 divided by the heating value per gallon of fuel being used. Example 8. What would be the estimated seasonal oil consumption of a boilerburner unit in Minneapolis of a building having a calculated heat loss of 192,000 Btu per hour, burning 144,000 Btu per gallon oil and operating at a seasonal efficiency of 60 per cent, if the outside design temperature for Minneapolis is --20 F, and the inside design temperature is 70 F? Solution. From Table 6, under 60 per cent efficiency and opposite the bottom column, find the uncorrected U to be 0.00476 gal per 1000 Btu hourly heat loss. From Table 5, the correction multiplier for --20 F outside design temperature is 0.778. Solving, 0.778 X 0.00476 = 0.00370. Making a further correction for the heating value: 140 000 0.0037 X i ll'oQQ " 6-063 gsl per 1000 Btu per hour calculated heat loss per degree- day. , From Table 3, the average degree-days for Minneapolis number 7850, and from the problem N = 192. Substituting in Equation 3: F = 0.0036 X 7850 X 192 = 5426 gal. Table 6. Unit Fuel Consumption3 Constants for Onh Burr 40 Gal Oil per Sq Ft Steam Radiator.. 0.00172 Gal Oil per Sq Ft Hot Water Radiator._____ _____ 0.00108 Gal Oil per 1000 Btu per Hour Heat Loss.... ........ 0.00715 Efpicebnct in Per Cent 50 60 70 0.00137 0.00114 0.00098 0.00086 0.00072 0.00062 0.00571 0.00476 0.00409 80 . 0.00086 0.00054 0.00358 Based on a heating value of 140.000 Btu per gallon, c. HABS.lHotehkS pemission from Degree-Day Handbook (Second Edition. 1937), by C. Strock and Table 7. Unit Fuel Consumption3 Constants for Coal>> Unit 40 Lb Coal per Sq Ft Steam Radiator.. 0.0200 per Sq Ft Hot Water Radiator. 0.0125 Lb Coal per 1000 Btu per Hour Heat Loss...... 0.0825 Efficibnct in Per Cent 50 0.0160 60 0.0133 70 0.0114 0.0100 0.0084 0.0072 0.0666 0.0550 0.0471 80 0.0100 0.0063 0.0412 Based on a heating value of 12.000 Btu per pound. r by permission H. B. Hotchkiss. . from Degree-Day Handbook, (Second Edition, 1937). by C. Strock and 235 w HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Estimating Coal or Coke Consumption . Coal or coke consumption estimates can be made in exactly the same way as for oil. The uncorrected values of U are given in Table 7. These constants apply only to inside design temperatures of 70 F and an outside design temperature of 0 F, and correction must be made for other con ditions by use of the multiplying factors in Table 5. Table 7 is based on 12,000 Btu per pound coal and for other heating values of coal, values in Table 7 must be multiplied by the ratio of 12,000 divided by the heating value of fuel used. Example 9. A building in Marquette, Mich., has an hourly heat loss at design con ditions of 240,000 Btu per hour. If the inside design temperature is to be 70 F and the outside design temperature is --10 F, what will be the estimated normal seasonal coal consumption for heating if 12,000 Btu per pound fuel is burned at a 50 per cent seasonal efficiency, and what part of the total will be used during November, December, and January? Solution. From Table 7, U uncorrected, is 0.0666 lb of coal per 1000 Btu per hour heat loss. Correcting for the outside design temperature, Table 5, the corrected value of U is 0.875 X 0.0666 = 0.0583. From Table 3, D is 8693 and from the problem N is 240 Substituting in Equation 3: F = 0.0583 X 240 X 8693 = 121,632 lb. Fuel used over any period is, according to the theory of the degree-day, proportional to the number of degree-days during the period. From Table 3, the average number of degree-days for November, December, and January in Marquette are 960, 1302, and 1500, a total of 3762. The yearly total is 8693, so that during these three months the estimated consumption is: fH X 121'p32 r 52'638 lb' Estimating Steam Consumption In estimating steam consumption the efficiency is not ordinarily a factor and is assumed at 100 per cent. Ordinarily low pressure steam with a heating value of 1000 Btu per pound is used so.that no correction is necessary for heating value in the usual case. In comparing values from different cities, correction should be made for design temperature (see Table 5) when the unit figures are in terms of square foot of radiator or 1000 Btu per hour calculated heat loss, but not when the values are in terms of building volume or floor space. Consideration has been given to the difference in steam utilization of different types of buildings and Table 84 shows'actual average units for these various types. These figures are obtained from operating results in 196 buildings located in 21 different cities in the United States. Being averages, and for small groups in each type, the figures may need con siderable modification to allow for local variations. It should be especially noted that the steam used for heating hot water is included in the values given in Table 8, but in the case of office buildings, the steam for heating only is also shown. Presentation of the unit consumption in three ways permits making the estimate if either the calculated heat loss op the volume of net heated space in the building is known. '- 4The Heat Requirements of Buildings, by J. H. Walker and G. H. Tuttle (A.S.H.V.E. Transactions. VoL 41. 1935, p. 171). 236 CHAPTER 12. HEAT AND FUEL UTILIZATION Table 8. Steam Consumption for Various Classes of Buildings3 (Heating Season Only) ' Building Classification No. OF Buildings Listed Steam Consumption Pounds per Deqree-Dat--65 F Basis*! Per M Cu Ft Per M Sq Ft Per M Btu of Heated of Radiatore _per-Hr of , Space Surface Heat Loesb Apartments.............................................................. Hotels............ ............................................................ Printing------------------------------------------- :................ Clubs and Lodges................................................. Retail Stores............................................................ Theatres.............. ...................................................... Loft and Mfg........................................................... Auto Sales and Service......... Churches--.................-............................................ Department StoresTM ................................. Garages (Storage)'. _______ Offices (Total).................................................... Offices (Heating only)................................. 16 10 12 7 10 18 6 16 7 8 `6 14 6 35 35 1.78 1.46 1 .32 1.25 Q.Qfi 0.90 0.90 0.89 n 88 (LS3 0.58 0.57 0.42 1.09 0.975 97.5 80.6 04 ? 105'5 77 0 80^6 75.0 72.3 6^ 2 49.4 60.7 72.3 70.0 65.4 0.359s' 0.371 0.268 0.498 0.283 0.238 0.283 0.256 tlncludes steam for heating d.omestic water for heating season only. bHeat loss calculated for maximum design condition (in most cases 70 F inside, zero outside), cEquivalent steam radiator surface. dThe figures are a numerical--not a weighted--average for the several buildings in each class, a Based on zero consumption at 55 F. Example 10. A store in Detroit with a heating system designed to maintain 70 F inside in 0 F weather has 1700 sq ft of equivalent direct steam radiator surface, and uses only moderate quantities of hot water. What would be the estimated average yearly steam consumption of purchased steam for heating and for hot water during the heating season? , Solution. According to Table 8, a store (0 to 70 F conditions) would use 80.6 lb of steam per thousand square feet of radiation per degree-day, including winter hot water. From Table 3, Detroit has 6490 degree-days per normal year. Inserting in Equation (3): . F = 80.6 X 1.7 X 6490 = 876,930 lb of steam. . Table 9. Building Load Factors and Demands of Some Detroit Buildings3 Building Classification Clubs and Lodges Hotels.. Printing........... Offices__ Apartments............... Retail Stores........ Auto Sales and Service..... Banks....... Churches. . Department Stores.......... 1 heatres * Load Factob 0.318 0.316 0.287 0.263 0.255 0.238 0.223 0 ?03 0!l58 0.138 0.126 Lb or Demand fee Hb Soper Ft of Equivalent Installed Radiator Surface 0.248 0.152 0.145 Report of Commercial Relations Committee, Proceeding!:. Notional District Healing Association. 1932; 237 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 MAXIMUM DEMANDS AND LOAD FACTORS In one form of district heating rates, a portion of the charge is based upon the maximum demand of the building. The maximum demand may be measured in several different ways. It may be taken as the instan taneous peak or as the rate of use during any specified interval. . One method is to take the average of the three highest hours during the winter. These figures are available for a number of buildings in Detroit, as shown in Table 9. These maximum demands were measured by an attachment on the condensation meter and therefore represent the amounts of condensation passed through the meter in the highest hours, rather than the true rate at which steam is supplied. There might be slight differences in these two quantities due to time lag and to storage of condensate in the system, but wherever this has been investigated it has been found to be negligible. The load factor of a building is the ratio of the average load to the maximum load and is an index of the utilization habits. Thus, in Table 9, the theatres, operating for short hours, have a load factor of 0.126 as compared with the figure of 0.318 for clubs and lodges. SEASONAL EFFICIENCY The task of predicting fuel consumption within reasonably accurate limits is a simple one where sufficient experience data are available for the fuel in question. Such data can be analyzed to the point where average unit factors can be determined and expressed in such terms as, for example, average gallons of oil actually, burned per square foot of calculated steam radiator surface per degree-day. The unit U can be inserted directly in Equation 3 without reference to efficiency. Such experience factors are available for gas (see Table 4) and for district steam (Table 8), but not for coal or oil. , Since values of TJ are not available for. oil or coal, an assumed seasonal efficiency E must be used. Selection of a value.for this E must be made with caution for its use implies a meaning not commonly associated with the word efficiency and consequently is frequently misleading. ' The input of heat to a building consists not only of the energy in' the fuel but that from occupants, the sun, appliances, processes, and all other sources. In many cases these make up, over a period, an important percentage of the total heat required, and if they are not taken into account a calculation of efficiency can show a figure over 100 per cent. For this and other reasons the actual seasonal efficiency, is a difficult thing to determine. Published data are widely scattered and insufficient. From the available published material it is found that the seasonal effi ciency varies over a wide range, depending on the fuel used, and it varies widely even for a given fuel. For example, in a recent survey of 30 houses in one locality there was found a variation of from 45 to 75 per cent in the utilization efficiency depending on the fuel5. , Heat Losses and Efficiencies of Fuels in Residential Heating, by R. A. Sherman and R. C. Cross, (A.S.H.V.E. Transactions. Vol. 43, 1937, p. 185). 238 Chapter 13 HEATING BOILERS Cast-Iron Boilers, Steel Boilers, Special Heating Boilers, Gas-Fired Boilers, Hot Water Supply Boilers, Furnace Design, Heating Surface, Testing and Rating Codes, Output Efficiency, Selection of Boilers, Connections and Fittings, Erection, Oper ation and Maintenance, Boiler Insulation STEAM and hot water boilers for low pressure heating work are built in a wide variety of types, many of which are illustrated in the Catalog Data Section, and are classified as (1) cast-iron sectional, (2) steel fire tube, (3) steel water tube, and (4) special. CAST-IRON BOILERS Cast-iron boilers usually fall into one of two general classifications (1) rectangular pattern with vertical sections and rectangular grate commonly known as sectional boilers, (2) round pattern with horizontal pancake sections and circular grates commonly known as round boilers. A few boilers of the sectional type use outside header construction where each section is independent of the other and the water and steam con nections are made externally through these headers. The majority of boilers, however, both sectional and round, are assembled with push nipples and tie rods at the top and bottom of the sections in which case water and steam connections are internal. The present trend in design of sectional boilers is to use a large top push nipple so that in a steam boiler the water line may be carried through the top push nipple thereby per mitting circulation of water between adjacent sections at both the top and bottom of the water content of the. boiler. The primary purpose of this construction is to eliminate the necessity of connecting the sections below the water line with an external header to permit circulation of the water from one section to the other which is necessary in the case of a steam boiler equipped with an indirect water heater for summer-winter hot water supply. . Round and sectional boilers may be increased in size by the addition of sections which in the case of sectional boilers also increases the grate area. The grate area of round boilers remains the same as additional sections are added. Cast-iron boilers are usually shipped knocked down. This facilitates handling at the place of installation where assembly is made in that separate sections can be taken into or out of basements and other places more or less inaccessible after the building is constructed. This feature 239 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 is of importance in the original installation of the boiler and also in making repairs to or replacing a damaged boiler at a later date. Cast-iron boilers may be designed to burn efficiently one kind of fuel only or various kinds of fuel. Practical combustion rates for coal-fired boilers are given in Table 1. Many recent designs of oil burning boilers have been designed exclusively for oil fuel and in some cases for both oil and gas. The present trend in the design of boilers for hand firing is, however, to design them so they will be suitable for ready conversion to and efficient operation with oil and stoker firing even after the boiler has been installed and has-been operating for a period of time on one type of fuel. ' Table 1. Practical Combustion Rates for Coal-Fired Heating Bciilers Oper ating AT Maximum Load on Natural Draft of from Vs in. to H in. Water Kind or Coal No. 1 Buckwheat Anthracite Anthracite Pea Anthracite Nut and Larger Bituminous Sq Ft Grate Ls or Coal per Sq Ft Gratb fsb Hour Up to 4 5 to 9 10 to.14 . 15 to 19: 20 to 25 . - 3 3^ .4 m 5 - Up to 9 10. to 19 ' 20 to 25 ` 5 5H 6 Up to 4 5 to 9 10 to 14 JR fn 19" 20 to 25 8 9 10 11 13 Up to 4 5 to 14 15 and above . 9.5 12 15.5 steel boilers usually have higher combustion rates for grate areas exceeding IS sq ft than those indicated In this table. Capacities of cast-iron boilers range from that required for small residences up to about 18,000 sq ft of radiation. For larger loads boilers must be installed in multiple. The maximum allowable working pressure for cast-iron boilers is limited by the A.S.M.E. Code to 15 lb per. square inch for steam boilers. Hot water boilers are .usually limited to 30 lb per square inch maximum working pressure but may be designed, for higher pressures where required for heating purposes or for hot water supply where the boiler must withstand high local water pressures. STEEL BOILERS Steel heating boilers may be classified according to (a) positidn of combustion gas with respect to tube surface, (b) arrangement and con struction of furnaces, and (c) type of fuel and method of firing. " Fire tube boilers are those in which the gases of combustion pass through the tubes and the boiler water circulates around them. In water 240 CHAPTER 13. HEATING BOILERS tube boilers, the gases circulate around the tubes and the water passes through them. Steel heating boilers may be'furnished with integral water jacketed furnaces or arranged for refractory lined brick or refractory lined jacketed furnaces. Those with integral water jacketed furnaces are called portable firebox boilers and are the most commonly used type. They may be either fire tube or water tube and are furnished for any fuel and method of firing used in heating boiler practice. They are usually shipped from the factory in one piece, ready for piping. Bridge-walls and smoked less furnace parts are shipped in place when furnished. Boilers with refractory lined furnaces may be either fire tube or water tube. They also may be arranged for any fuel or method of firing. Refractory furnaces are usually installed in such boilers after they are set. SPECIAL HEATINC BOILERS A special type of boiler, known as the magazine feed boiler, has . been developed for the burning of small sizes of anthracite and coke. These are built of both cast-iron and steel, and have a large fuel carrying capa city which results in longer firing periods than would be the case with the standard types using buckwheat sizes of coal. Special attention must be given to insure adequate draft and proper chimney sizes and connections. Oil-burner boiler units, in which a special boiler has been designed with a furnace shaped to meet the general requirements of oil burners, or are specially adapted to one particular burner, have been developed by-a number of manufacturers. These usually are compact units with the burner and all controls enclosed within an insulated steel jacket. Ample furnace volume is provided for efficient combustion, and the heating surfaces are proportioned for effective heat transfer. Consequently; higher efficiencies are obtainable than with the ordinary coal-fired boiler designed primarily for hand firing and converted to oil firing. GAS-FIRED BOILERS Gas boilers have assumed a well-defined individuality. The usual boiler is sectional in construction with a number of independent burners placed beneath the sections. In most boilers each section has its own burner. In all cases the sections are placed quite closely together, much closer than would be possible when burning a soot-forming fuel. The effort of the designer is always to break the hot gas up into thin streams, so that all particles of the heat-carrying gases can come as close as possible to the heat-absorbing surfaces. Because there is no fuel bed resistance and because the gas company supplies the motive power to draw in the air necessary for combustion (in the form of the'initial gas pressure), draft losses through gas boilers are low. (See Chapter 11.) .' Most gas-fired boilers carry the approval of the American Gas,As.soT ciation. In order to obtain this approval the boilers must be submitted to the American Gas Association Testing Laboratory and meet the Approval Requirements for Central Heating Gas Appliances issued by the American Gas Association. ' The boiler ratings must be such that they meet the; limitations as set forth in these Approval Requirements. , 241 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 HOT WATER SUPPLY BOILERS Boilers for hot water supply are classified as direct, if the water heated passes through the boiler, and as indirect, if the water heated does not come in contact with the water or steam in the boiler. Direct heaters are built to operate at the pressures found in city supply mains and are tested at pressures from 200 to 300 lb per square inch. The life of direct heaters depends almost entirely on the scale-making properties of the water supplied. If water temperatures are maintained below 140 F the life of the heater will be much longer than if higher temperatures are used, owing to decreased scale formation and minimized corrosion below 140 F. Direct water heaters in some cases are designed to burn refuse and garbage. Indirect heaters generally consist of steam boilers in connection with heat exchangers of the coil or tube types which transmit the heat from the steam to the water. This type of installation has the following advantages: 1. The boiler operates at low pressure. 2. The boiler is protected from scale and corrosion. 3. The scale is formed in the heat exchanger in which the parts to which the scale is attached can be cleaned or replaced. The accumulation of scale does not affect efficiency although it will affect the capacity of the heat exchanger. 4. Discoloration of water may be prevented if the water supply comes in contact with only non-ferrous metal. Where a steam heating system is installed, the domestic hot water usually is obtained from an indirect heater placed below the water line of the boiler. Indirect heaters may also be used with hot water heating systems to obtain domestic hot water and should be located as high as possible with respect to the boiler for most satisfactory performance. FURNACE DESIGN Good efficiency and proper boiler performance are dependent on cor rect furnace design embodying sufficient volume for burning the par ticular fuel at hand, which requires thorough mixing of air and gases at a high temperature with a velocity low enough to permit complete.com- bustion of all the volatiles. On account of the small amount of volatiles contained in coke, anthracite, and semi-bituminous coal, these fuels can be burned efficiently with less furnace volume than is required for bi tuminous coal,'the combustion space being proportioned according to the amount of volatiles present. Combustion should take place before the gases are cooled by the boiler heating surface, and the volume of the furnace must be sufficient for this purpose. The furnace temperature must be maintained sufficiently' high to produce complete combustion, thus resulting in a higher COj content and the absence of CO. Hydrocarbon gases ignite at temperatures varying from 1000 to 1500 F. . The question of furnace proportions, particularly in regard to mechani cal stoker installations, has been given some consideration by various manufacturers' associations. Arbitrary values have been recommended for minimum dimensions. A customary rule-of-thumb method of figuring furnace volumes is to allow 1 cu ft of space for a maximum heat release 242 CHAPTER 13. HEATING BOILERS of 50,000 Btu per hour. This value is equivalent to allowing approxi mately 1 cu ft for each developed horsepower, and it is approved by most smoke prevention organizations. The setting height will vary with the type of stoker. In an overfeed stoker, for instance, all the volatiles must be burned in the combustion chamber and, therefore, a greater distance should be allowed than for an underfeed stoker where a considerable portion of the gas is burned while passing through the incandescent fuel bed. The design of the boiler also may affect the setting height, since in certain types the gas enters the tubes immediately after leaving the combustion chamber, while in others it passes over a bridge wall and toward the rear, thus giving a better opportunity for combustion by obtaining a longer travel before entering the tubes. ; To secure suitable furnace volume, especially for mechanical stokers or oil burners, it often is necessary either to pit the stoker or oil burner, or; where water line conditions and headroom permit, to raise the boiler on a brick foundation setting. Smokeless combustion of the more volatile bituminous coals is furthered by the use of mechanical stokers. (See Chapter 11.) Smokeless comr bustion in hand-fired boilers burning high volatile solid fuel is aided (1) by the use of double grates with down-draft through the upper grate, (2) by the use of a curtain section through which preheated auxiliary air is introduced over the fire toward the rear of the boiler, and (3) by the intro duction of preheated air through passages at the front of the boiler. All three methods depend largely on mixing secondary air with the partially burned volatiles and causing this mixture to pass over an incandescent fuel bed, thus tending to secure more complete combustion than is pos sible in boilers without such provision. ' HEATING SURFACE Boiler heating surface is that portion of the surface of the heat transferapparatus in contact with the fluid being heated on one side and the gas or refractory being cooled on the other side. Heating surface on which the fire shines is known as direct or radiant surface and that in contact with hot gases only, as indirect or convection surface. The amount of heating surface, its distribution and the temperatures on either side thereof influence the capacity of any boiler. Direct heating surface is. more valuable than indirect per square foot because it is subjected to a higher temperature and also, in the case of solid fuel, because it is in position to receive the full radiant energy of the fuel bed. The heat transfer capacity of a radiant heating surface may be as high as 6 to 8 times that of an indirect surface. This is one of the reasons why the water legs ofsome boilers have been extended, especially in the case of stoker firing where the extra amount of combustion chamber secured by an extension of the water legs is important. For the same reason, care should be exercised in building a refractory combustion chamber in an oil-burning boiler so as not to screen any more of this valuable surface with refractories than is necessary for good combustion. The effectiveness of the heating surface depends on its cleanliness, its location in the boiler, and the shape of the gas passages. The area of the 243 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 gas passages must not be so small as to cause excessive resistance to the flow of gases where natural draft is employed. Inserting baffles so that the heating surface is arranged in series with respect to the gas flow increases boiler efficiency and reduces stack temperature and increases . the draft loss through the boiler. Heat Transfer Rates Practical rates of heat transfer in heating boilers will average about 3300 Btu per sq ft per hour for hand-fired boilers and 4000 Btu per sq ft per hour for mechanically fired boilers when operating at design -load. When operating at maximum load1 these values will run between 5000 and 6000 Btu per sq ft per hour. Boilers operating under favorable conditions at the above heat transfer rates will give exit gas temperatures that are considered consistent with good practice. ' TESTINC AND RATING CODES The Society has adopted-four solid fuel testing codes, a solid fuel rating code and an oil fuel testing code. A.S.H.V.E. Standard and Short Form Heat Balance Codes for Testing Low-Pressure Steam Heating Solid Fuel Boilers--Codes 1 and 2--(Revision of June 1929)*, are intended to provide a method for conducting and reporting tests to determine heat efficiency and performance characteristics. A.S.H.V.E. Performance Test Code for Steam Heating Solid Fuel Boilers--Code No. 3--(Edition of 1929)* is intended for use with A.S.H.V.E. Code for Rating Steam Heating Solid Fuel Hand-Fired Boilers*. The object of this test code is to specify the tests to be conducted and to provide a method for conducting and reporting tests to determine the efficiencies and performance of the boiler. The A.S.H.V.E. Standard Code for Testing Steam' Heating Boilers Burning Oil Fuel* is intended to provide a standard method for con ducting and reporting tests to determine the heating efficiency and per formance characteristics when oil fuel is used with steam heating boilers. In 1938 the Society adopted a Standard Code for Testing Stoker-Fired Steam Heating Boilers5 which is intended to provide a test method for determining the efficiency and performance characteristics of any stoker or boiler combination' burning any type of solid fuel such as anthracite or bituminous coal. The Steel Heating Boiler Institute has adopted a method for the rating of low pressure boilers based on their physical characteristics and ex pressed in square feet of steam or water radiation or in Btu per hour as given in Table 2. The detailed requirements of this code were outlined in Chapter 13 of The Guide 1939. The Institute of Boiler and Radiator Manufacturers has also adopted a method of rating cast-iron heating boilers based upon performance obtained under tests. This code became effective August 1, 1939 for sectional boilers of 20 in. width grate or less, but the Institute intends eventually to expand the code to apply to all - `For definitions of design load and maximum load see page 246. . *See A.S.H.V.E. Transactions. Vol. 35, 1929, pp. 322 and 332. See A.S.H.V.E. Transactions, Vol. 36, 1930. p. 42. See A.S.H.V.E. Transactions. Vol. 37, 1931, p. 23. *See A.S.H.V.E. Transactions. Vol. 44, 1938, p.*366. 244 CHAPTER 13. HEATING BOILERS Table 2. Steel Heating Boiler Standard Ratings3 Hand-Fired Rating Mechanicallt-Fibed Rating Steam Radiation SqFt Catalog Water Radiation SqFt Btu per Hour in Thou sands Net Load Steam Radiation SqFt | Heating Surface SqFt Grate Area SqFt Steam Radiation SqFt Catalog Water Radiation Sq Ft Net Load Furnace Vol ume, Oil, Gas Btu per Steam * or Bituminous Hour in Radiation Coal Cu Ft Thousands Sq Ft 1,800 2,200 2,600 3,000 3,500 4,000 4,500 5,000 6,000 7,000 8,500 10,000 12,500 15,000 17,500 20,000 25,000 30,000 35,000 2,880 3,520 4,160 4,800 5,600 6,400 7,200 8,000 9,600 11,200 13,600 16,000 20,000 24,000 28,000 32,000 40,000 48,000 56,000 432 528 624 720 840 960 1,080 1,200 1,440 1,680 2,040 2,400 3,000 3,600 4,200 4,800 6,000 7,200 8,400 1,389 1,702 2,020 2,335 2,732 3,135 3,540 3,945 4,770 5,608 6,885 8,197 10,417 12,500 14,584 16,667 20,834 25,000 29,167 129 158 186 215 250 286 322 358 429 500 608 715 893 1,072 1,250 1,429 1,786 2,143 2,500 7.9 8.9 9.7 10.5 11.4 12.2 13.4 14.5 16.4 18.1 20.5 22.5 25.6 28.4 30.9 33.2 37.4 41.2 44.7 2,190 2,680 3,160 3,650 4,250 4,860 5,470 6,080 7,290 8,500 10,330 12,150 15,180 18,220 21,250 24,290 30,360 36,430 42,500 3,500 4,280 5,050 5,840 6,800 7,770 8,750 9,720 11,660 13,600 16,520 19,440 24,280 29,150 34,000 38,860 48,570 58,280 68,000 525 643 758 876 1,020 1,166 1,312 1,459 1,749 2,040 2,479 2,916 3,643 4,372 5,100 5,829 7,286 8,743 10,200 1,695 2,089 2,461 2-,853 3,335 3,830 4,330 4,834 5,850 6,885 8,490 10,125 12,650 15,183 17,708 20,242 25,300 30,359 35,417 15.7 19.2 22.6 26.1 30.4 34.8 39.1 43.5 52.1 60.8 73.8 86.8 108.5 130.2 151.8 173.5 216.9 260.3 303.6 Adopted by the Steel Heating Boiler Institute in cooperation with the Bureau of Standards, United States Department of Commerce Simplified Practice Recommendations R 167-36. sizes of boilers. Methods of testing hand-fired and oil-fired, boilers are specified and are referred to as IBR testing codes. ' BOILER OUTPUT Boiler output as defined in A.S.H.V.E. Performance Test Code for Steam Heating Solid Fuel Boilers (Code No. 3) is the quantity of heat available at the boiler nozzle with the boiler normally insulated. It should be based on actual tests conducted in accordance with this code. This output is usually stated in Btu and in square feet of equivalent heat ing surface (radiation). According to the A.S.H.V.E. Standard Code for Rating Steam Heating, Solid Fuel Hand-Fired Boilers, the performance data should be given in tabular or curve form on the following items for at least five outputs ranging from maximum down to 35 per cent of maxi mum: (1) fuel available, (2) combustion rate, (3) efficiency, (4) draft tension, (5) flue gas temperature. The only definite restriction placed on setting the maximum output is that priming shall not exceed 2 per cent. These curves provide complete data regarding the performance of the ' boiler under test conditions. Certain other pertinent information, such as grate area, heating surface and chimney dimensions is desirable also in forming an opinion of how the boiler will perform in actual service. The output of large heating boilers is frequently stated in terms of boiler horsepower instead of in Btu per hour or square feet of equivalent radiation. ` 245 % HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 BOILER EFFICIENCY The term efficiency as used for guarantees of boiler performance is usually construed as follows: 1. Solid Fuels. The efficiency of the boiler alone is the ratio of the heat absorbed by the water and steam in the boiler per pound of combustible burned on the grate to the calorific value of 1 lb of combustible as fired. The combined efficiency of boiler, furnace and grate is the ratio of the heat absorbed by the water and steam in the boiler per pound of fuel as fired to the calorific value of 1 lb of fuel as fired. , 2. Liquid and Gaseous Fuels. The combined efficiency of boiler, furnace and burner is the ratio of the heat absorbed by the water and steam in the boiler per pound or cubic foot of fuel to the calorific value of 1 lb or cubic foot of fuel respectively. Solid fuel boilers usually show an efficiency of 50 to 75 per cent when operated under favorable conditions at their rated capacities. Infor mation on the combined efficiencies of boiler, furnace and burner has resulted from research conducted at Yale University in cooperation with the A.S.H.V.E. Research Laboratory and the American Oil Burner Association6. SELECTION OF BOILERS Estimated Design Load: The load, stated in Btu per hour or equivalent direct radiation, as estimated by the purchaser for the conditions of inside and outside temperature for which the amount of installed radiation was determined is the sum of the heat emission of the radiation to be actually installed plus the allowance for the heat loss of the connecting piping plus the heat requirement for any apparatus requiring heat connected with the system. The estimated design load is the sum of the following three items7: 1. The estimated heat emission in Btu per hour of the connected radiation (direct, indirect or central fan) to be installed. . 2. The estimated maximum heat in Btu per hour required to supply water heaters or other apparatus to be connected to the boiler. 3. The estimated heat emission in Btu per hour of the piping connecting the radiation and other apparatus to the boiler. . Estimated Maximum Load: Construed to mean the load stated- in Btu per hour or the equivalent direct radiation that has been estimated by the purchaser to be the greatest or maximum load that the boiler will be called upon to carry. The estimated maximum load is given by8: 4. The estimated increase in the normal load in Btu per hour due to starting up cold radiation. This percentage of increase is to be based on the sum of Items.-l, 2 and 3 and the heating-up factors given in Table 3. Other things to be considered are: ' ' 5. Efficiency with hard or soft coal, gas, or oil firing, as the case may be.* A.S Boilers, . Rbsbarch1m..v-. ------------------------------------,-------------- -. Powers (A.S.H.V.E. Transactions, Vol. 38, 1932, p. 317). 'A S.H.V.E. Code of Minimum Requirements for the Heating and Ventilation of Buildings (Edition of 1929). ' " *Loc. Cit, Note 7. CHAPTER J3. HEATING BOILERS 6. Grate area with hand-fired coal, or fuel burning rate with stokers, oil, or gas. 7. Combustion space in the furnace. 8. Type of heat liberation, whether continuous or intermittent, or a combination of both. 9. Miscellaneous items consisting of draft available, character of attendance, pos sibility of future extension, possibility of breakdown and headroom in the boiler room. Radiation Load . The connected radiation (Item 1) is determined by calculating the heat losses in accordance with data given in Chapters 5, 6 and 7, and dividing by 240 to change to square feet of equivalent radiation as explained in Chapter 14. For hot water, the emission commonly used is 150 Btu per square foot, but the actual emission depends on the temperature of the medium in the heating units and of the surrounding air. (See Chapter 14.) Although it is customary to use the actual connected load in equivalent square feet of radiation for selecting the size of boiler, this connected load usually represents a reserve in heating capacity to provide for infiltration Table 3. Warming-up Allowances for Low Pressure Steam and ___________________ Hot Water Heating Boilers3. b. c orDesign Load (Representing Summation Items 1,2, and 3,d Bta per Hour Equivalent Square Feet of Radiation^ Percentage Capacity to Add tor Warming Up Up to 100,000 100,000 to 200,000 200,000 to 600,000 600,000 to 1,200,000 1,200,000 to 1,800,000 Above 1,800,000 Up to 420 420 to 840 840 to 2500 2500 to 5000 5000 to 7500 Above 7500 . 65 60 55 50 45 40 This table is taken from the A.S.H.V.E. Code of Minimum Requirements for the Heating and Venti lation of Buildings, except that the second column has been added for convenience in interpreting the design load in terms of equivalent square feet of radiation. bSee also Time Analysis in Starting Heating Apparatus, by Ralph C. Taggert (A.S.H.V.E. Transac tions. Vol. 19,1913. p.292); Report of.A.S.H V.E. Continuing Committee on Codes for Testing and Rating Steam Heating Solid Fuel Boilers (A.S.H.V.E. Transactions. Vol. 36. 1930, p. 35); Selecting the Rieht Size Heating Boiler, by Sabin Crocker (Seating, Piping and Air Conditioning, March, 1932). This table refers to hand-fired, solid fuel boilers. A factor of 20 per cent over design load is adeauate when automatically-fired fuels are used (see Fig. 1). H <1240 Btu per square foot. in the various spaces of the building to be heated, which reserve, however, is not in use at all places at the same time, or in any one place at all times.' For a further discussion of this subject see Chapter 6. Hot Water Supply Load When the hot water supply (Item 2) is heated by the building heating boiler, this load must be taken into consideration in sizing the boiler. The allowance to be made will depend on the amount of water heated and its temperature rise. A good approximation is to add 4 sq ft of equivalent radiation for each gallon of water heated per hour through a temperature range of TOO F. For more specific information, see Chapter 44. Piping Tax (Item 3) : It is common practice to add a flat percentage allowance to the equivalent connected radiation to provide for the heat loss from bare and covered pipe in the supply and return lines. The use of a flat allowance of 247 p HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 25 per cent for steam systems and-35 per cent for hot water systems is preferable to ignoring entirely the load due to heat loss from the supply and return lines, but better practice, especially "when there is much bare pipe, is to compute the emission from both bare and covered pipe surface in accordance with data in Chapter 40. A chart is shown in Fig. 1 indicat ing percentage allowances for piping and warming-up which are applic able to automatically-fired heating plants using steam radiation. With direct radiation served by bare supply and return piping the percentages may be higher than those stated, while in the case of unit heaters where the output is concentrated in a few locations, the piping tax may be 10 per cent or less. Warming-Up Allowance The warming-up allowance represents the load due to heating the boiler and contents to operating temperature and heating up cold radiation and piping. (See Item 4.) The factors to be used for determining the CHAPTER 13. HEATINC BOILERS Selection Based on Heating Surface and Grate Area -Where performance curves are not available, a good general rule for conventionally-designed boilers is to provide 1 sq ft of boiler heating surface for each 14 sq ft of equivalent radiation (240 Btu per square foot) represented by the design load consisting of connected radiation, piping tax and domestic water heating load. As stated in the section on Boiler Output, this is equivalent to allowing 10 sq ft of boiler heating surface per "' Fig. 1. Percentage Allowance for Piping and Warming-up allowance to be made should be selected from Table 3 and should be applied to the estimated design load as determined by Items 1, 2 and 3. While in every case the estimated maximum load will exceed the design load if adequate heating response is to be achieved, there is however, no object in over-estimating the allowances, as the only effect would be to reduce the time of warming-up by a few minutes. Otherwise, it might result in firing .the boiler unduly,and increasing the cost of operation. Performance Curves for Boiler Selection In the selection of a boiler to meet the estimated load, the A.S.H.y.E. Standard Code for Rating Steam Heating Solid Fuel Hand-Fired Boilers recommends the use of performance curves based on actual tests con ducted in accordance with the A.S.H.V.E. Performance Test Code for Steam Heating Solid Fuel Boilers (Code No. 3), similar.to the typical curves shown in Fig. 2. It should be understood that performance data apply to test conditions and that a reasonable allowance should be made for decreased output resulting from soot deposit, poor fuel or inefficient attention. ' 248 BTU PER LB. (3,CSS Fig. 2. Typical Performance Curves for a 36-in. Cast-Iron Sectional Steam Heating Boiler, Based on the A.S.H.V.E. Code for Rating Steam Heating Solid Fuel Hand-Fired Boilers boiler horsepower. In this case it is assumed that the maximum load including the warming-up allowance will be provided for by operating the boiler in excess of the design load, that is, in excess of the 100 per cent rating on a boiler-horsepower basis. Due to the wide variation encountered in manufacturers' ratings for boilers of approximately the same capacity, it is advisable to check the grate area required for heating boilers burning solid fuel by means of the following formula: Cx FXE 249 (1) HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 where . G = grate area, square feet. H = required total heat output of the boiler, Btu per hour (see Selection of Boilers, p. 246). . C = combustion rate in pounds of dry coal per square foot of grate area per hour, depending on the kind of fuel and size of boiler as given in Table 1. F = calorific value of fuel, Btu per pound. E = efficiency of boiler, usually taken as 0.60. Example 1. Determine the grate area for a required heat output of the boiler of 500,000 Btu per hour, a combustion rate of 6 lb per hour, a calorific value of 13,000 Btu per pound, and an efficiency of 60 per cent. _ 500,000 6 X 13,000 X 0.60 10.7 sq ft The boiler selected should have a grate area not less than that deter mined by Formula 4. With small boilers where it is desired to provide sufficient coal capacity for approximately an eight-hour firing period plus a 20 per cent reserve for igniting a new charge, more grate area may be required depending upon the depth of the fuel pot. ' Selection of Steel Heating Boilers ' Ratings obtained from the previously mentioned Steel Healing Boiler Institute code are intended to correspond with the estimated design load based on the sum of items 1, 2 and 3 outlined on page 246. Boilers with less than 128 sq ft of heating surface are' classified as residence, size. An insulated residence boiler for oil or gas, not convertible, may parry a net load expressed in square feet of steam radiation of not more than 17 times the square feet of heating surface in the boiler, provided the boiler manufacturer guarantees it to be capable of operating at a maxi mum output of not less than 150 per cent of net load rating with overall efficiency of not less than 75 per cent with at least two different makes of each type of standard commercial burner recommended by the boiler manufacturer. If the heat loss from the piping system exceeds 20 per cent of the installed radiation, the excess is to be considered as a part of the net load. When the estimated heat emission of the piping (connecting radiation, and other apparatus to the boiler) is not known the net load to be con sidered for the boiler may be determined from Table 2. Selection of Gas-Fired Boilers : Gas-heating appliances should be selected in accordance with the percentage allowances given in Fig. 1. These factors are for thermo statically-controlled systems; in case manual operation is desired, a warming-up allowance of 100 per cent is recommended by the A.G.A. A gas boiler'selected by the use of the A.G.A. factors will be the minimum size boiler which can carry the load. From a fuel economy standpoint, it may be advisable to select a somewhat larger boiler and then- throttle the gas and air adjustments as required. This will tend to give a low stack temperature with high efficiency and at the same time provide reserve capacity in case the load is under-estimated or more is added in the future. 250 CHAPTER 13. HEATING BOILERS Conversions The conversion of a coal or oil boiler to gas burning is simpler than the reverse since little.furnace volume need be provided for the proper com bustion of gas. When a solid fuel boiler of 500 sq ft (or less) capacity is converted to gas burning, the necessary gas heat units should be approxi mately double the connected load. The presumption for a conversion job is that the boiler is installed and probably will not be made larger; therefore, it is a matter of setting a gas-burning rate to obtain best results, with the available surface. Assuming a combustion efficiency of 75 per cent for a conversion installation the boiler output would be 2 X 0.75 = 1.5 times the connected load, which allows 50 per cent for piping tax and pickup. In converting large boilers, the determination of the re quired Btu input should not be done by an arbitrary figure or factor but should be based on a detailed consideration of the requirements and characteristics of the connected load. An efficient conversion installation depends upon the proper size of flue connection. Often the original smoke breeching between the boiler and chimney is too large for gas firing, and in this case, flue orifices can be used. They are discs provided with an opening of the size for the gas input used in this boiler. The size should be based on 1 sq in. of flue area for each 7500 hourly Btu input. If dampers are found in the breeching they should be locked in position so that they will not interfere with the normal operation of the gas burners at maximum flow. In the case of large boiler conversions, automatic damper regulators proportion the position of the flue dampers to the amount of gas flowing and may be substituted for existing dampers. Generally in residence conversions automatic dampers are not of the proportioning type but close the flue during the off periods of the gas burners. Automatic shut-off dampers should be located between the back draft diverter and the chimney flue. Automatic dampers are usually designed to operate with electric contact mechanism, but frequently an arrangement is utilized which functions with mechanical fluid or gas pressure. . Physical Limitations As it will usually be found that several boilers will meet the speci fications, the final selection may be influenced by other considerations, as: 1. Dimensions of boiler. . 2. Durability under service. 3. Convenience in firing and cleaning. 4. Adaptability to changes in fuel and kind of attention. 5. Height of water line. In large installations, the use of several smaller boiler units instead of one larger one will obtain greater flexibility and economy by permitting the operation, at the best efficiency, of the required number of units according to the heat requirements. Space Limitations Boiler rooms should, if possible, be situated at a central point with respect to the building and should be designed for a maximum of natural 251 HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 light. The space in front of the boilers should be sufficient for firing, stoking, ash removal and cleaning or renewal of flues, and should be at least 3 ft greater than the length of the boiler firebox. A space of at least 3 ft should be allowed on at least one side of every, boiler for convenience of erection and for accessibility to the various dampers, cleanouts and trimmings. The space at the rear of the boiler should be ample for the chimney connection and for cleanouts. With , large boilers the rear clearance should be at least 3 ft in width. The boiler room height should be sufficient for the location of boiler accessories and for proper installation of piping. In general the ceiling height for small steam boilers should be at least 3 ft above the normal boiler water line. With vapor heating, especially, the height above the boiler water line is of vital importance. When steel boilers are used, space should be provided for the removal and replacement of tubes. CONNECTIONS AND FITTINGS Steam or water outlet connections perferably should be the full size of the manufacturers' tappings in order to keep the velocity of flow through the outlet reasonably low and avoid fluctuation of the water line and undue entrainment of moisture, and should extend vertically to the maximum height available above the boiler. Particular attention should be given to fitting connections to secure con formity with the A.S.M.E. Boiler Construction Code for Low Pressure Heating Boilers. Attention is called in particular to pressure gage piping, water gage connections and safety valve capacity. Steam gages should be fitted with a water seal and a shut-off consisting of a cock with either a tee or lever handle which is parallel to the pipe when the cock is open. Steam gage connections should be of coppe.r or brass when smaller than 1 in. I.P.S? if the gage is more than 5 ft from the boiler connection, and also in any case where the connection is less than Yi in. I.P.S. Each steam or vapor boiler should have at least one water gage glass and two or more gage cocks located within the range of the visible length of the glass. The water gage fittings or gage cocks may be direct connected to the boiler, if so located by the manufacturer, or may be mounted on a separate water column. No connections, except for combustion regu lators, drains or steam gages, should be placed on the pipes connecting the water column and the boiler. If the water column or gage glass is con nected to the boiler by pipe and fittings, a cross, tee or equivalent, in which a cleanout plug or a drain valve and piping may be attached, should be placed in the water connection at every right-angle turn to facilitate cleaning. The water line in steam boilers should be carried at the level specified by the boiler manufacturer. Safety valves should be capable of discharging all the steam that can be generated by the boiler without allowing the pressure to rise more than 5 lb above the maximum allowable working pressure of the boiler. This* 252 A.S.M.E. Code, Identification of Piping Systems. 252 CHAPTER 13. HEATING BOILERS should be borne in mind particularly in the case of boilers equipped with mechanical stokers or oil burners where the amount of grate area has little significance as to the steam generating capacity of the boiler. Where a return header is used on a cast-iron sectional boiler to distribute the returns to both rear tappings, it is advisable to provide full size plugged tees instead of elbows where the branch connections enter the return tappings. This facilitates cleaning sludge from the bottom of the boiler sections through the large plugged openings. An equivalent clean out plug should be provided in the case of a single return connection. Blow-off or drain connections should be made near the boiler and so arranged that the entire system may be drained of water by opening the drain cock. In the case of two or more boilers separate blow-off connec tions must be provided for each boiler on the boiler side of the stop valve on the main return connection. Water service connections must be provided for both steam and water boilers, for refilling and for the addition of make-up water to boilers. This connection is usually of galvanized steel pipe, and is made, to the return main near the boiler or boilers. For further data on pipe connections for steam and hot water heating systems, see Chapters 16 and 17 and the A.S.M.E. Boiler Construction Code for Low Pressure Heating Boilers. Smoke Breeching and Chimney Connections. The breeching or smoke pipe from the boiler outlet to the chimney should be air-tight and as short and direct as possible, preference being given to long radius and 45-deg instead of 90-deg bends. The breeching entering a brick chimney should not project beyond the flue lining and where practicable it should be grouted from the inside of the chimney. 'A-. thimble or sleeve grout usually is provided where the breeching enters a brick chimney. Where a battery of boilers is connected into a breeching each boiler should be provided with a tight damper. The breeching for a battery of boilers should not be reduced in size as it goes to the more remote boilers. Good connections made to a good chimney will usually result in a rapid response by the boilers to demands for heat. ERECTION, OPERATION, AND MAINTENANCE The directions of the boiler manufacturer always should be read before the assembly or installation of any boiler is started, even though the contractor may be familiar with the boiler. All joints requiring boiler putty or cement which cannot be reached after assembly is complete must be finished as the assembly progresses. 1 The following precautions should be taken in all installations to prevent damage to the boiler: 1. There should be provided proper and convenient drainage connections for use if the boiler is not in operation during freezing weather. 2. Strains on the boiler due to movement of piping during expansion should be prevented by suitable anchoring of piping and by proper provision for pipe expansion and contraction. 3. Direct impingement of too intense local heat upon any part of the boiler surface, as with oil burners, should be avoided by protecting the surface with firebrick or other refractory material. 253 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 4. Condensation must flow back to the boiler as rapidly and uniformly as possible. Return connections should prevent the water from backing out of the boiler. 5. Automatic boiler feeders and low water cut-off devices which shut off the source of heat if the water in the boiler falls below a safe level are recommended for boilers mechanically fired. Boiler Troubles A complaint regarding boiler operation generally will be found to be due to one of the following: 1. The boiler fails to deliver enough heat. The cause of this condition may be: (a) poor draft; (6) poor fuel; (c) inferior attention or firing; (d) boiler too small; (e) improper piping; (f) improper arrangement of sections; (g) heating surfaces covered with soot; and (h) insufficient radiation installed. 2. The water line is unsteady. The cause of this condition may be: (o) grease and dirt in boiler; (b) water column connected to a very active section and, therefore, not showing actual water level in boiler; and (c) boiler operating at excessive output. 3. Water disappears from gage glass. This may be caused by: (a) priming due to grease and dirt in boiler; (b) too great pressure difference between supply and return piping preventing return of condensation; (c) valve closed in return line; (d). connection of bottom of water column into a very active section or thin waterway; and () improper connections between boilers in battery permitting boiler with excess pressure to push returning condensation into boiler with lower pressure. . 4. Water is carried over into steam main. This may be caused by: (a) grease and dirt in boiler; (6) insufficient steam dome or too small steam liberating area; (c) outlet con nections of too small area; (d) excessive rate of output; and (e) water level carried higher than specified. 5. Boiler is slow in response to operation of dampers. This may be due to: (n) poor draft resulting from air leaks into chimney or breeching; (b) inferior fuel; (c) inferior attention; (d) accumulation of clinker on grate; and (e) boiler too small for the load. 6. Boiler requires too frequent cleaning of flues. This may be due to: (a) poor draft; (b) smoky combustion; (c) too low a rate of combustion; and (d) too much excess air in firebox causing chilling of gases. 7. Boiler smokes through fire door. This may be due to: (a), defective draft in chimney or incorrect setting of dampers; (6) air leaks into boiler or breeching; (c) gas outlet from firebox plugged with fuel; (d) dirty or clogged flues; and () improper reduction in breeching size. 8. Low carbon dioxide. This may be due on oil burning boilers to: (a) improper ad justment of the burner; (b) leakage through the boiler setting; (c) improper fire caused by a fouled nozzle; or (d) to an insufficient quantity of oil being burned. Cleaning Steam Boilers All boilers are provided with flue dean-out openings through which the heating surface can be reached by means of brushes or scrapers. Flues of solid fuel boilers should be cleaned often to keep the surfaces free of soot or ash. Gas boiler flues and burners should be cleaned at least once a year. Oil burning boiler flues should be examined periodically to deter mine when cleaning is necessary. The grease used to lubricate the cutting tools during erection of new piping systems serves as a carrier for sand and dirt, with the result that a scum of fine particles and grease accumulates on the surface of the water in all new boilers, while heavier particles may settle to the bottom 254 , CHAPTER 13. HEATINC BOILERS of the boiler and form sludge. These impurities have a tendency to cause foaming, preventing the generation of steam and causing an unsteady waterline. This unavoidable accumulation of oil and grease should be removed by blowing off the boiler as follows: If not already provided, install a surface blow connection of at least 1 ]4, in. nominal pipe size with outlet extended to within 18 in. of the floor or to sewer, inserting a valve in line close to boiler. Bring the water line to center of outlet, raise steam pres sure and while fire is burning briskly open valve in blow-off line. When pressure recedes, close valve and repeat process adding water at intervals to maintain proper level. As a final operation bring the pressure in the boiler to about 10 lb, close blow-off, draw the fire or stop burner, and open drain valve. After boiler has cooled partly, fill and flush out several times before filling it to proper water level for normal service. The use of soda, or any alkali, vinegar or any acid is not recommended for cleaning heating boilers because of the difficulty of complete removal and the possibility of subsequent injury, after the cleaning process has been completed. Insoluble compounds have been developed which are effective, but special instructions on the proper cleaning compound and directions for its use in a boiler, as given by the boiler manufacturer, should be carefully followed. It is common practice when starting new installations to discharge heating returns to the sewer during the first week of operation. This prevents the passage of grease, dirt or other foreign matter into the boiler and consequently may avoid the necessity of cleaning the boiler. During the time the returns are being passed to the sewer, the feed valve should be cracked sufficiently to maintain the proper water level in the boiler. Care of Idle Heating Boilers Heating boilers are often seriously damaged during summer months due chiefly to corrosion resulting from the combination of sulphur from the fuel with the moisture in the cellar air. At the end of the heating season the following precautions should be taken: 1. All heating surfaces should be cleaned thoroughly of soot, ash and residue, and the heating surfaces of steel boilers should be given a coating of lubricating oil on the fire side. 2. All machined surfaces should be coated with oil or grease. 3. Connections to the chimney should be cleaned and in case of small boilers the pipe should be placed in a dry place after cleaning. 4. If there is much moisture in the boiler room, it is desirable to drain the boiler to prevent atmospheric condensation on the heating surfaces of the boiler when they are below the dew-point temperature. Due to the hazard of some one inadvertentlybuilding a fire in a dry boiler, however, it is safer to keep the boiler filled with water. A hot water system usually is left filled to the expansion tank. 5. The grates and ashpit should be cleaned. 6. Clean and repack the gage glass if necessary. 7. Remove any rust or other deposit from exposed surfaces by scraping with a wire brush or sandpaper. After boiler is thoroughly cleaned, apply a coat of preservative paint where required to external parts normally painted. . 8. Inspect all accessories of the boiler carefully to see that they are in good working order. In this connection, oil all door hinges, damper bearings and regulator parts. 255 HEATINC VENTILATING . AIR CONDITIONING GUIDE 1940 BOILER INSULATION Insulation for cast-iron boilers is of two general types: (1) plastic material or blocks wired on, cemented and covered with canvas or duck; and (2) blocks, sheets or plastic material covered with a metal jacket furnished by the boiler manufacturer. Self-contained steel firebox boilers usually are insulated with blocks, cement and canvas, or rock wool blankets; HRT boilers are brick set and do not require insulatibn beyond that provided in the setting. It is essential that die insulation on a boiler and adjacent piping be of non-combustible material as even slow-burning insulation constitutes a dangerous fire hazard in case of low water in the boiler. 256 Chapter 14 RADIATORS AND GRAVITY CONVECTORS Heat Emission of Radiators and Convectors, Types of Radi ators, Output of Radiators, Heating Effect, Heating Up the Radiator and Convector, Enclosed Radiators, Convectors, Selection, Code Tests, Gravity-Indirect Heating Systems HE accepted terms for heating units are: (I) radiators, for direct Tsurface heating units, either exposed, enclosed, or shielded, which emit a large percentage of their heat by radiation; and (2) convectors, for heating units haying a large percentage of extended fin surface and which emit heat principally by convection. Convectors are dependent upon enclosures to provide the circulation by gravity of large volumes of air. HEAT EMISSION OF RADIATORS AND CONVECTORS All heating units emit heat by radiation and convection. The resultant heat from these processes depends upon whether or not the heating unit is exposed or enclosed and upon the contour and surface characteristics of the material in the units. An exposed radiator emits less than half of its heat by radiation, the amount depending upon the size and number of sections. When the radiator is enclosed or shielded, radiation is further reduced. The balance of the emission is by conduction to the air in contact with the heating surface, and the resulting circulation of the air warms by convection. A convector emits practically all of its heat by conduction to the air surrounding it and this heated air is in -turn transmitted by convection to the rooms or spaces to be warmed, the heat emitted by radiation being negligible. TYPES OF RADIATORS Present day radiators may be classified as tubular, wall, or window types, and are generally made of cast-iron. Catalogs showing the many designs and patterns available now include a junior size sometimes known as slim tube radiation. The tubes in these radiators are materially smaller, and they are compactly assembled in less space than those of the standard radiator. Pipe coils are assemblies of standard pipe or tubing (1 in. to 2 in.) which ' are used as radiators. In older practice these coils were commonly used in factory buildings, but now wall type radiators are most frequently used for this service. When coils are used, the miter type assembly is to be 257 i HEATING VENTILATING AIR CONDITIONING GUIDE 1940 preferred as it best cares for expansion in the pipe. Cast manifolds or headers, known as branch tees, are available for this construction. OUTPUT OF RADIATORS The output of a radiator can be measured only by the heat it emits. The old standard of comparison used to be square feet of actual surface, but since the advance in radiator design and proportions, the surface area alone is not true index of output. (The engineering unit of outputs is the Mb or 1000 Btu.) However, during the period of transition from the old to the new, radiators may be referred to in terms of equivalent square feet. For steam service this is based on an emission of 240 Btu per hour per square foot and for hot water service 150 Btu per hour per square foot. Table 1. Variation in Dimensions and Catalog Ratings of 10-Section Tubular Radiators (Steam) Wirlt.K rtf Rarliatrtr Length per Section. ______Inches 3 4.6-5.1 2.5 4 6.0-7.0 2.5 5 8.0-8.9 2.5 6 .7 - 9.1-10.4- 2.5 11.4-12.8 ' 2.5-3.0 . Hbiqbt with Legs--Ikches Heat Emission---Equivalent Squabs Fret 13-14 16-18 20-21 22-23 25-26 30-32 36-38 20 25.0-32.5 : 28.5 30.0-38.3 15.0-17.5 20.0-22.5 25.0-31.2 30 36.7-45.0 20.0-21.3 25 30.0-33.9 35 40.0-45.2 ; 20.0-26.7 25.0-27.5 32.5-39.8 37.5-40.0 50.0-53.5 25.0-30.9 33.3-35.0 40.0-48.6 50 63.3-62.5 30.0-36.7 40.0-42.5 50.0-56.5 60 70.0-75.4 . Table 1 illustrates the difficulty in tabulating tubular radiator outputs since there is so much variation in design between the products of the different manufacturers. Only on the four-tube and six-tube sizes is t^iere any practical agreement in output value. The heat emission values appear as square feet but are entirely empirical, being based on the heat emission of the radiator and riot on the measured surface. An average value of 300 Btu per actual square foot of surface area per hour has been found for wall radiators one section high placed with their bars vertical. Several recent tests1 show that this value will be reduced from 5 to 10 per cent if the radiator is placed near the ceiling with the bars horizontal and in an air temperature exceeding 70 F. When radiators are placed near the ceiling, there is usually so noticeable a difference in temperature between the floor level and the ceiling that it becomes dif ficult to heat, the living zone of a room satisfactorily. The heat emission of pipe coils placed vertically on a wall with the pipes horizontal is given in Table 2. This has been developed from avail able data and does not represent definite results of tests. For such coils the heat emission varies as the height of the coil. The heat emission of each pipe of ceiling coils, placed horizontally, is about 126 Btu, 156 Btu, 'University of Illinois, Engineering Experiment Station Bulletin No. 223, p. 30. 258 CHAPTER 14. RADIATORS AND GRAVITY CONVECTORS Table 2 Heat Emission of Pipe Coils Placed Vertically on a Wall (Pipes Horizontal) Containing Steam at 215 F and Surrounded with Air at 70 F Btu per linear foot of coil per hour (not linear feet of pipe) ----Size of Pips 1 In. IJilN. min. 132 162 185 252 312 348 440 545 616 567 702 793 651 796 907 732 907 1020 812 1005 1135 and 175 Btu per linear foot of pipe, respectively, for 1-in., lj^-in., and lj^-in. coils. . Effect of Paint ,, The prime coat of paint on a radiator has no material effect on the heat output, but the finishing coat may influence the radiation emission and thus affect the heat output: Within the range of temperatures at which radiators, operate, color has no appreciable influence on the radiation emitted^ Thus, finishing coats of oil paints of various colors will give the same results. However, a bronze paint, applied as the finish coat will change the character of the surface and reduce the amount of heat emitted by radiation: No paint has a noticeable effect on the portion of heat which is given off by convection. The larger the proportion of direct radiating surface, the greater will be the effect of any finish coat of paint which changes the character of the surface. Available tests are on oldr style column type radiators which give results as shown in Table 3. Effect of Superheated Steam : Available research data indicate that there is probably a decrease in heat transfer rate for a radiator or gravity convector with superheated steam in comparison with saturated steam at the same temperature. The decrease is probably small for low temperatures of superheats and additional tests are necessary with varying degrees of superheat to establish accurate comparisons for all types of radiators and convectors*. Table 3. Effect of Painting 32-in. Three Column, Six-Section Cast-Iron Radiator* Radiator No. Finish Ahba SqFt Coefficient of Heat Tranb. Btu Relative Heating Value Per Cent i Bare iron, foundry finish....................... ......... 27 2 One coat of aluminum bronze------------------- 27 3 Gray paint dipped.................................... -- 27 4 One coat dull black heat resistant paint.... 27 1.77 1.60 1.78 1.76 100.5 90.8 . 101.1 100.0 Comparative Testa of Radiator Finishes, by W. H. Seveins (A.S.H.V. E. Transactions, VoL 33, 1927, p. 41). Tests of Radiators with Superheated Steam, by R. C. Carpenter (A.S.H.V.E. Transactions. Vol. 7, 1901, p. 206). 259 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 room temp in deg F -22 a 552 tb Test R-E2, 5-tube rad -22 z 5.62 tb Test R-E61.3-tube rad -27 s 5.42 tb Test R-E10.1-tube panel rad -23 550 lb Test R-2c, (Bui 223) wad rad D12 3 < 67 Net lb of steam condensed per hour HEIGHT ABOVE FLOOR IN FEET Fig. 1. Room Temperature Gradients and Steam Condensing Rates for Four Types of Cast-Iron Radiators with a Common Temperature at the 60-In. Level Note that the steam condensations are practically the same for all four radiators when the same air temperature of 69 F is maintained at the 60-in. level. HEATING EFFECT For several years the heating effect of radiators has been considered by engineers in order to use it for the rating of radiators and in the: design of heating systems. Heating effect is the useful output of a radiator, in the comfort zone of a room, as related to the total input of the radiator*. . The results of tests conducted at the University of Illinois are shown in Figs. 1 and 2*. For the four types of radiators shown, the following con clusions are given: . ; . HEIGHT ABOVE FLOOR IN FEET Fig. 2. Room Temperature Gradients and Steam Condensing Rates for Four Types of Cast-Iron Radiators with a Common Temperature at the 30-In. Level Note that the steam condensations are different for all four radiators when the same air temperature of 68 F is maintained at the SO-in. level. The Heating Effect of Radiators, by Dr. Charles Brabbet (A.S.H.V.E. Transactions,. Vol. 33, 1927, p. 33). A.S.H.V.E. Research Report No. 962--The Application of the Eupatheoscope for Measuring the Performance of Direct Radiators and Convectors in Terms of Equivalent Temperature, by A. C. Willard. A. P. KraU and M. K. Fahnestock (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 303). A.S.H.V.E.. Research Report No. 905--Steam Condensation an Inverse Index of Heating Effect, by A. P. Kratz and M. K. Fahnestock (A.S.H.V.E. Transactions. Vol. 37, 1931, p. 475). 260 CHAPTER 14. RADIATORS AND GRAVITY CONVECTORS 1 The heating effect of a radiator cannot be judged solely by the amount of steam' condensed withjn the radiator. 2 Smaller floor-to-ceiling temperature differentials can be maintained with long, low, thin direct radiators, than is possible with high, direct radiators. ' 3* The larger portion of the floor-to-ceiling temperature differential in a room of average ceiling height heated with direct radiators occurs between the floor and the brratlu^g comjQrt |eve| (approximately 2 ft-6 in. above floor) is below the breathing line levei (approximately 5 ft-0 in. above floor), and temperatures taken at the breathing line may not be indicative of the actual heating effect of a radiator in the room. The comfort-indicating temperature should be taken below the breathing line level. . 5. High column radiators placed at the sides of window openings do not produce as comfortable heating effects as long, low, direct radiators placed beneath window openings*. TIME ELAPSED AFTER STEAM TURNED INTO RADIATOR, MINUTES Fig. 3. Chart Showing the Steam Demand Rate for Heating Up a Cast-Iron Radiator with Free Air Venting and Ample Steam Supply HEATING UP THE RADIATOR AND CONVECTOR The maximum condensation occurs in a heating unit when the steam is first turned on6. Fig. 3 shows a typical curve for the condensation rate in pounds per hour for the time elapsing after steam is turned into a castiron radiator. The data are from tests on old-style column type radiators. In practice the rate of steam supply to the heating unit while heating up is frequently retarded by controlled elimination of air through air valves or traps. Automatic control valves may also retard the supply of steam. Vacuum types of air venting valves may be used to reduce the length of the venting periods. ENCLOSED RADIATORS The general effect of an enclosure placed about a direct radiator is to restrict the air flow, diminish the radiation and, when properly designed, Effect of Two Types of Cast-Iron Steam Radiators in Room Heating, by A. C. Willard and M. K. Fahnestock (Heating, Piping and Air Conditioning, March,-1930, p. 135). A.S.H.V.E. Research Report No. 1067--The Cooling and Heating Rates of a Room with Different Types of Steam Radiators and Convectors, by A. P. Kratz, M. K. Fahnestock and E. L. Broderick (A.S.H.V.E. Transactions. Vol. 43, 1937, p. 389). 261 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 improve the heating effect. Recent investigations7 indicate that in the design of the enclosure three things should be considered: 1. There should be better distribution of the heat below the breathing line level to produce greater heating comfort and lowered ceiling temperatures. 2. The lessened steam consumption may not materially change the radiator heating performance. 3. The enclosed radiator may inadequately heat the space. A comparison between a bare or exposed radiator (A) and the same radiator with a well-designed enclosure (3), with a poorly-designed enclosure (C), and with a cloth cover (D) will' illustrate the relative heating effects. In Fig. 4 the curve (B) reveals that the enclosed radiator used less steam than the exposed radiator, but gave a satisfactory heating performance. A well-designed shield placed oyer a radiator gives about j CHAPTER 14. RADIATORS AND GRAVITY CONVECTORS CONVECTORS OR CONCEALED HEATERS Although any standard radiator may be concealed in a cabinet or other enclosure so that the greater percentage of heat is conveyed to the room by convection thereby resulting in a form of gravity convector, generally better results are obtained with specially designed units which permit a free circulation of a larger volume of air at moderate tempera tures. Since air stratifies according to temperature, moderate delivery temperatures at the outlet of the enclosure reduce the temperature dif ferential between the floor and ceiling and accordingly accomplish the desired heating effect in the living zone. Fig. 4. .Steam Consumption of Exposed and Concealed Radiators . the same heating effect. Curve (C) shows the unsatisfactory effects produced by improperly designed enclosures. Curve (D) shows that the effect of a cloth cover extending downward 6 in. from the top of the radiator was to make the performance unsatisfactory and inadequate. Practically all commercial enclosures and shields for use on direct radiators are equipped with water pans for the purpose of adding moisture to the air in the room. Tests8 show that an average evaporative rate of about 0.235 lb per square foot of water surface per hour may be obtained from such pans, when the radiator is steam hot and the relative humidity in the room is between 25 and 40 per cent. This source of supply of moisture alone is not adequate to maintain a relative humidity above 25 per cent on a zero day. University of Illinois, Engineering Experiment Station Bulletins Nos. 192 apd 223. and Investigation of Heating Rooms with Direct Steam Radiators Equipped with Enclosures and Shields, by A. C. Willard, A. P. Kratz, M. K. Fahnestock and S. Konzo (A.S.H.V.E. Transactions, Vol. 35, 1929, p. 77). University of Illinois, Engineering Experiment Station Bulletin No. 230, p. 20. . 262 Fig. 5. Typical Concealed Convector Using Specially Designed Heating Unit Fig. 5 shows a typical built-in convector. The heating element con^ sisting of a large percentage of fin surface is usually shallow in depth and placed low in the enclosure in order to produce maximum chimney effect in the enclosure. The air enters the enclosure near the floor line just below the heating element, is moderately heated in passing through the core and delivered to the room through an opening near the top of en closure. Since the air can only enter the enclosure at the floor line, the cooler air in the room which always lies at this level, is constantly being withdrawn and replaced by the warmer air. This air movement accom plishes the desired reduction in temperature differentials and assures maximum comfort in the living zone. : The Convector Manufacturers Association has adopted the A.S.H.V.E. 263 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Standard9 in the formulation of its ratings and has compiled a tentative standard of heating effect allowances for various enclosure heights to be included in the ratings by its members. , All published ratings bearing the title C.M.C. Ratings (Convector Manu facturers Certified Ratings) indicate that the convectors have been tested in accordance with the A.S.H.V.E. Code by an impartial and disinterested laboratory and that the ratings have been approved by the Standardiza tion Committee of the Convector Manufacturers Association. Concealed heaters or convectors are generally sold as completely built-in units. The enclosing cabinet should be designed with suitable air inlet and outlet grilles to give the heating element its best performance. Tables of capacities are catalogued for various lengths, depths and heights, and combinations are available in several styles for installations, such as the wall-hung type, free-standing floor type, recess type set flush with wall or offset, and the completely concealed type. Most of these types may be arranged with a top outlet grille in a plane parallel with the floor, although the front outlet is practically standard. In cases where enclosures are to be used but are not furnished by the heater manufacturer, it is important that the proportions of the cabinet and the grilles be so designed that they will not impair the performance of the assembled convector. It is impor tant that the enclosure or housing for the convector fit as snugly as pos sible so that the air to be heated must pass through the convector and cannot besby-passed in the enclosure. The output of a convector, for any given length and depth, is a variable of the height. .'Published ratings are generally given in terms of equiva lent square feet, corrected for heating effect. However, an extended surface heating unit is entirely different structurally and physically from a direct radiator and, since it has no area measurement corresponding to the heating surface of a radiator, many engineers believe that the per formance of convectors should be stated in Btii's. For steam convectors, as for radiators, 240 Btu per hour may be taken as an equivalent square foot of radiation. When more than one heating unit is used, one mounted above the other in the same cabinet, the output of the upper unit or units will be materially less than that of the bottom unit. RADIATOR AND CONVECTOR SELECTION The capacity of a radiator varies as the 1.3 power, and that of a con vector10 as the 1.5 power of the temperature difference between the heating medium and the surrounding air in the case of the radiators, and the entering air in the case of the convector. It is obvious that for conditions other than the basic ones with the heating medium at a temperature of 215 F, and the room temperature at 70 F in the case of a radiator, and the inlet air temperature at 65 F in the case of a convector, the heat emission will be other than 240 Btu per square foot of rating. Table 4 shows factors by which radiation requirements, as determined by dividing heat load by 240, shall be multiplied to obtain proper radiator A S H.V.E. standard Code for Testing and Rating Concealed Gravity Type Radiation (Steam), (A.S.H.V.E. Transactions, Vol. 37, 1931. p. 367); (Hot Water), (A.S.H.V.E. Transactions, Vol. 39. 1933. p. 237). "A S.H.V.E. Research Report No. 998--Factors Affecting the Heat Output of Convectors, by A. P. Kratz, M. K. Fahnestock, and E. L. Broderick (A.S.H.V.E. Transactions. Vol. 40. 1934, p. 443). 264 . CHAPTER 14. RADIATORS AND GRAVITY CONVECTORS Table .4. Correction Factors for Direct Cast-Iron Radiators and Convector Heaters2 ' Steam HnATnra Factors fob Direct - . Pom Medium Cast-Iron Radiators Factoas fob Convbctobs ' Aptbox. Tsmp.F Gage Vacuum In. Hg. Aba. Lb per Sq In. ' Steam os Waxes 80 com Temperatubs F 75 70 65 .60 55 50 Inlet Am Temperature F. . . 80 75 70 65 60 55 50 22.4 3.7 203 4.7 17.7 6.0 14.6 73 10.9 93 6.5 ' 11.5 LbperSqlo. 1 15.6 6 21 15 30 ... 27 ' 52 42 67 150 238 236 2.17 2.00 1.86 1.73 1.62 3.14 2.83 237 235 2.15 1.98 134 160 2.17 2.00 1.86 1.73 1.62 1.52 1.44 237 235 2.15 1.98 1.84 1.71 139 170 1.86 1.73 1.62 132 1.44. 135 1.28 2.15 1.98 1.84 1.71 139 1.49 1.40 180 1.62 132 1.44 135 1.28 1.21 1.15 1.84 1.71 139 1.49 1.40 132 1.24 190 1.44 135 1.28 1.21 1.15 1.10 1.05 139 1.49 1.40 132 1.24 1.17 Ml 200 1.28 1.21 1.15 1.10 1.05 1.00 0.96 1.40 132 1.24 1.17 Ml 1.05 1.00 215 uo 1.05 1.00 0.96 0.92 0.88 0.85 1.17 Ml 1.05 1:00 41.95 0.91 037 230 0.96 0.92 0.88 0.85 0.81 0.78 0.76 1.00 0.95 0.91 0.87 MW 0.79 0.76 250 0.81 0.78 0.76 0.73 0.70 0.68 0.66 0.83 0.79 0.76 0.73! 0170- 0.68 0.65 270 0.70 0.68 0.66 0.64 0.62 0.60 0.58 0.70 0.68 0.65 0.63 0.60 038 036 300 0.58 0.57 0.55. 033 032 031 0.49 036 034 033 031 0.49 0.48 0.47 To determine the size of a radiator or a convector for a given space divide the heat loss in Btu per hour by 240 and multiply the result by the proper factor from the above table. To determine the heating capacity of a radiator or a convector under conditions other than the basic ones with the heating medium at a temperature of 215 F, and the room temperature at 70 F in the case of a radiator, and the inlet air temperature at 65 F in the case of a convector, divide the heating capacities at the basic conditions by the proper factor from the above table. or convector sizes from published rating tables for room temperatures ranging between 50 and 80 F as well as for steam or water temperatures from 150 to 300 F. For other room and heating medium temperatures, the factor is determined by the following formulae: . . For radiators: /215 - 70\i 3 V U - tr ) where For convectors: - /215 - 6S\l! C" " V -k-h ) C, = correction factor. ' f3 = steam temperature, degrees Fahrenheit. It = room temperature, degrees Fahrenheit. <i = average inlet air temperature, degrees Fahrenheit. As previously indicated, the output of radiators and convectors is still designated by the terms of older practice, but this is gradually giving place to an engineering method of designating heat emission. The A.S.H.V.E. has adopted the following standards: Code for Testing Radiators (1927); Codes for Testing and Rating Concealed Gravity Type Radiation (Steam), 1931, and (Hot Water), 1933, (see also A.S.H.V.E. Transactions, Vol 41, 1935, p. 38). For steam services the actual condensation weight is taken without any allowance for heating effect; for hot water services the weight 'of' circu lated water is used without allowance for heating effect. In all cases the total heat transmission varies as the 1.3 power for radiators11 and the 1.5 power for convectors19 of the temperature difference between that inside the radiator and the air in the room, and is expressed in Btu or Mb per hour. . ' "Loc. Cit. Note 9. "Loc- Cit. Notes 9 and 10. 265 HEATING VENTILATING AIR CONDITIONING CUIDEIIWO Standard test conditions specify either a steam pressure of l ib gage 15.6 lb per sq in. absolute (215 F) or an average hot water temperature of 170 F and a room temperature of 70 F (5 ft above floor)' for radiators, or an inlet air temperature of 65 F for convectors. The heating capacity of a steam radiator or steam convector is determined as follows: - Ht -- *- s (1) where fft = Btu per hour under test conditions. 'Wt = condensation in pounds per hour. htt => latent heat in Btu per pound. ; ' .. . . Ht may be converted to standard conditions of code ratings by using the proper correction factor from the following formulae: ; For radiators: ` ^ ,, /215 - 70\13 ( 145 V-S Ca = llY^t;) T') (2) For convectors: ,, /215 - 65V-5 _ (___ 150 V~ = \ Ts -W) _\Ts -T;/ (3) The output under standard conditions will be: where H, = Cs Ht : Cs = correction factor. ' Tb = steam temperature during test, degrees Fahrenheit. Tt = room temperature during test, degrees Fahrenheit. . . Ti = inlet air temperature during test, degrees Fahrenheit. i?B = heat emission rating under standard conditions, Btu per hour. .. W Similarly, for hot water convectors, the output under test conditions may be determined as follows: '"' - 3600 H = W (8. - 8,) (5) where,. .fl = Btu per hour under test conditions. . W = pounds of water handled during test. . 8i = average temperature of inlet water, degrees Fahrenheit. 8j = average temperature of outlet water, degrees Fahrenheit. .. .. ' . *' I = duration of test, seconds. -. To convert test results to standard conditions, the following correction factor is used:. 117700 -- 6655 C= V \\ll-s // 110055 \l-5 ' . (6) - It has been shown that when the exponent 1.5 is used the range of error is less than 3 per cent13 for convectors. uLoc. Cit. Note 10. 266 Chapter 15 STEAM HEATING SYSTEMS Gravity and Mechanical Retumt Gravity One-Pipe Air-Pent, Gravity Two-Pipe Air-Vent, Air Line Heating, One-Pipe Vapor, Two-Pipe Vapor, Atmospheric, Condensation Return, Vacu um, Sub-Atmospheric, Orifice, Zone Control, Condensation Return Pumps, Vacuum Heating Pumps, Traps STEAM heating systems may be classified according to the pipe arrangement, the accessories used, the method of returning the con densate to the boiler, the method of expelling air from the system, or the type of control employed. Information concerning the design and layout of steam heating systems will be found in Chapter 16. GRAVITY AND MECHANICAL RETURN Systems are classified as gravity or mechanical according to the method of returning the condensate from the system to the boiler. In gravity systems the condensate is returned by gravity due to the static head of water in the return pipes or mains. The elevation of the boiler water line must be sufficiently below the lowest heating unit, steam pipe or dry return pipe to permit the return by gravity. The water line difference forming the static head must be sufficient to overcome the maximum pressure drop in the system, including the pressure drop due to the condensing effect of the radiation. When radiator and drip traps are used, as in two-pipe vapor systems, the static pressure must also exceed the operating pressure of the boiler. The pressure drop caused by con densing rate of the radiation is especially important during those portions of the operating periods where changing pressure conditions prevail, as for example, when the system is being initially filled with steam. In systems where the condensate is wasted to the sewer no water line differ ence is required as is the case with closed systems. However, the waste of condensate may introduce conditions which warrant the use of an appropriate mechanical system. Whenever the conditions of a heating system are such that the returns from the radiation cannot gravitate to the boiler they must be returned by some mechanical means. In mechanical systems the condensate flows to a receiver by gravity and is then forced into the boiler against its pressure. In all instances the preferable practice is to provide for gravity flow even where a vacuum pump is used. The lowest parts of the supply side of the system must be kept sufficiently above the water line of the receiver to insure adequate drainage of water from the system. 267 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 There are three general types of mechanical return devices in common use, namely, (1) the mechanical return trap, (2) the condensation return pump, and (3) the vacuum return line pump. CHAPTER 15. STEAM HEATING SYSTEMS condensation flow, in opposite directions; In long steam mains it flows in the same direction as the steam and is removed from the main through the drip. Short mains may be arranged for the condensate to flow in a direction opposite the steam by sizing them.so the critical velocity is not exceeded. It is customary to drip the heel of each riser in buildings of several stories to avoid counter-flow of the steam and condensate in the riser branch. In buildings of One or two stories the condensate is returned to the steam main instead of being dripped.i Both types of risers are shown in Fig. 1, and riser connections are . shown in Figs. 2 and 3. A typical overhead down-feed system is illustrated in Fig. 4. While wet return mains need not be pitched toward the boiler to maintain steam circulation they should be pitched for drainage. Fig. 1. Typical Up-Feed Gravity One-Pipe Air-Vent System ... GRAVITY ONE-PIPE'AIR-VENT SYSTEM '-' This, system is the most common of all methods of steam heating; "especially for small size installations, 'due largely to its low cost and simplicity. - Fig. 2. Typical Steam Runout where Risers are Not Dripped Fig. 3. Typical Steam Runout where . ... Risers are Dripped The downward pitch of a one-pipe air-verit system is indicated in Fig. 1. Low points and ends of steam mains pitched down from the boiler, should be dripped. AH drips should be sealed below water line before connecting together. In the risers and radiator connections, steam and 268 ' * Fig. 4. Typical Down-Feed Gravity One-Pipe Air-Vent System To improve steam circulation in one-pipe systems quick vent air valves should be provided at the ends and at intermediate points where the steam main is brought to a higher elevation. It is desirable to install the air-vent valves about a foot ahead of the drips,, as indicated in Fig. 1, to prevent possible damage to their mechanisms by water. . The radiator valves may be the angle-globe, offset-corner pattern or gate type. Straight-globe and straight-corner type should not be used since the damming effect of the raised valve seat would interfere with the flow of condensation through the valve. Graduated valves cannot be used since the steam valves on this system must be fully open or fully closed to prevent the radiators filling with water arid creating a dangerous water line condition. With a one-pipe system the heat cannot be modu lated at the radiator, the Steam being either all on or all off. Systems and devices are available which make it possible to obtain a partial modulating effect from one-pipe heating systems. . .; 269 HEATING ; VENTILATING !AIR CONDITIONING GUIDE 1940 It is important to keep the lowest points of the steam mains and heating units sufficiently above the water line of the boiler to prevent flooding. The minimum water line difference depends on the initial steam pressure and piping pressure drop plus a safety factor for heating up. Steam pressure at ure ' end of main . i Return water -Water line of boiler - + ,ine -*Rlsewatftr . tine difference Fig. 5. Difference in Steam Pressure on Water in Boiler and at End of Steam Main - Referring to Fig. 5 it will be noted that the water in the wet return is a U-shaped container, with the boiler steam pressure on the top of the water at one end and the steam main pressure on the top of the water at the other end. The difference between these two pressures is the pressure drop in the system, the friction and resistance to the flow of steam in passing from the boiler to the far end of the main and the pressure reduction in consequence of the condensation occurring in the system. The water in the far end will CHAPTER 15. STEAM HEATINC SYSTEMS would require lA of 28 in., or 14 in. for the difference in steam pressure, 3 in; for the flow through the return, 4 in. to operate the check, and 6 in. for a factor of safety, making a total of 27 in. as the required distance. Higher pressure drops would increase the distance accordingly. . GRAVITY TWO-PIPE AIR-VENT SYSTEMS The gravity two-pipe system indicated in Fig. 6, is now considered obsolete although many of these systems are still in use in older buildings. The same general principles governing its piping design are used when connecting radiators as in other types of gravity systems where they must discharge their condensation to the wet return pipe. Separate supply and return mains and connections are required for each heating unit. Radiator valves are required in both the supply and return connection to the radiator, and air valves are installed on the heating units and the mains. Where the return main has to be located high to function as a Fig. 6. Typical Up-Feed Gravity Two-Pipe Air-Vent System rise sufficiently to overcome this difference in order to balance the pressures,-and it will rise far enough to produce a flow through the return pipe and overcome the resistance of check valves if installed. If a one-pipe steam system is designed, for example, for a total pressure drop of A lb. and utilizes an Underwriters' Loop instead of a check valve on the return, the rise in the water ievel at the far end of the return due to the difference in steam pressure would be Ye of 28 in. (28 in. head being equal to one pound per square inch), or 3*4 in. Adding 3 in. to overcome the resistance of the return main and 6 in. as a factor of safety for heating up gives 12A in. as the distance; the bottom of the lowest part of the steam main and all heating units must be above the boiler water line. The same system, however, installed and sized for a total pressure drop of Yi lb, and with.a check in the return. 270 Fig. 7. Method of Connecting Two-Pipe Gravity Returns to Dry Return Main dry return, it is advisable to connect the return risers to the dry return main through water seals, as shown in Fig. 7, to prevent steam from one riser entering another. The steam main in the down-feed system is carried to the top of the building, and the piping of the steam side is arranged as in the down-feed one-pipe gravity system. On the return side of the system, the piping is arranged in exactly the same manner as the up-feed gravity two-pipe system. .......... AIR LINE HEATING SYSTEMS . Both one- and two-pipe systems are at times provided with air valves which instead of venting to the atmosphere direct, vent to a return pipe system of small size, which in turn is vented to atmosphere or connected to a vacuum pump. These are known as one-pipe and tii>o-pipe air line systems. Where the air line is exhausted by a vacuum: pump they are termed one-pipe or two-pipe vacuum air line systems. ONE-PIPE VAPOR SYSTEM . The one-pipe vapor system operates under pressures at or near atmos pheric and returns its condensation to the boiler by gravity. In this 271 HEATING. VENTILATING AIR:CONDITIONING GUIDE 1940 system the automatic air valves are of special design to permit the ready release of air and prevent its ready return after it is expelled. The steam radiator valves are a type which, when opened, give a free and unob structed passageway for water. The piping is the same as for the one-pipe gravity system but sized so as to permit operation at a few ounces pressure. . TWO-PIPE VAPOR SYSTEM A two-pipe up-feed vapor system using separate supply and return pipes is shown in Fig. 8. The radiators discharge their condensation through thermostatic traps to the dry return pipe. These systems operate at'a few ounces pressure and above, but those with mechanical condensate return devices may operate at pressures upward of TO lb. The simplest CHAPTER 15. STEAM HEATING SYSTEMS not holding heat when the rate of steam generation is diminishing. Sys tems of this design should preferably be equipped with an automatic return trap to prevent water from backing out of the boiler. In installing the return trap a check valve is inserted in the return main.at a point near the'boiler and a vertical pipe is run up into the bottom of the return trap, .which is usually located with the bottom about 18 in. above the boiler .water line. Some traps are constructed so that they will operate when they are installed with their bottom as close as 8 in. above the boiler water line. On the other side of this connection a second check valve is installed Air vent and check Fig. 8. Typical Up-Ff.ed System with Automatic Return Trap3 Proper piping connections are essential with special appliances for pressure equalizing and air elimination. method of venting the system consists of a %-in. pipe with a check valve opening outward. Most systems employ various forms of vent valves, designed to allow the air to readily pass out of the system and to prevent its return. These systems permit control of the heat in the radiator by varying the opening of the graduated radiator valves. The boiler pressure is maintained at substantially constant pressure slightly above atmos pheric pressure. .' . These systems may be classified as (1) closed systems, consisting of those which have a device to prevent the return of air after it has once been expelled from the system, and which can operate at both super and sub- atmospheric pressures for a period of four to eight hours depending upon the tightness of the system and rate of firing,, and (2) open systems, com prising those which have the return line constantly open to the atmos phere without a check or other means to prevent the return of air. The open systems are not so popular because they have the disadvantage of 272 Fig. 9. Typical Connections for Automatic Return Trap in the main return just before it enters the boiler. Fig. 9 shows a typical connection for a automatic return trap. .. ' Down-Feed Two-Pipe Vapor System . .. ' In the down-feed two-pipe vapor system the steam is carried to the topi of the building, the top of the vertical riser constituting the`high point of the system, and the horizontal supply main is sloped down from this: location to the far ends of each branch. The branches are taken off the main from the bottom or at a 45-deg angle downward, with the runouts sloped toward the drops. Thus each branch from the main forms a drip and no accumulation of water is carried down any one drop. . The steam drops are carried down through the building with suitable reductions as the various radiator connections are taken off until the lowest radiator runout is reached. If the drop is only two or three stories high,, the portion feeding the bottom radiator should be increased One: 273 1 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 pipe size to provide for draining the riser, and if the drop is over three stories high it is well to increase the portion feeding the two lowest radi ators one or two pipe sizes, especially if the two lowest radiators are small and the normal size of drop required is 1 in. or less. The bottom.of each steam drop should terminate with a dirt pocket and be dripped as shown in Fig., 10. The returns on a down-feed vapor system are. the same as on an up-feed system. The runouts to the radiators and the radiator con nections of the down-feed system are the same as those for the up-feed system already described. . CHAPTER 15. STEAM HEATING SYSTEMS pressure line through a pressure reducing valve. The piping and other details are the same as for the vapor systems. F The return risers are connected in the basement into a common return main which slopes downward toward the vacuum pump. The vacuum pump withdraws the air and water from the system, separates the air from the water and expells it to atmosphere and pumps the water back to the boiler, or other receiver, which may be a feed-water heater or hot well. It is essential that no connection be made from the supply side to the return side at any point except through a trap. The desirable practice demands a return flowing to; the vacuum pump by an uninterrupted down- Fig. 10. Detail of Drip Connections at Bottom of Down-Feed Steam Drop CONDENSATION RETURN HEATING SYSTEMS When automatic condensation return pumps are substituted for the gravity return of a two-pipe vapor system they are known as return systems or return pump heating systems. A-typical installation of a motor driven automatic condensation unit'is illustrated in.Fig. 11. It will be noted that the returns are graded to cause flow by gravity to the vented receiver. As the receiver is filled, the float mechanism operates either a pilot or an across-the-line switch to start the pump, and upon emptying the tank, to disconnect the power and stop it. The pump may be used to deliver the condensate direct to the boiler, to a feed water heater or to raise the water to any higher elevation or pressure than that of the return line. A useful application, is a small condensation unit to handle a remote section of radiation that otherwise would be difficult to grade to the main return. VACUUM SYSTEMS In the vacuum system, a vacuum is maintained in the return line practically at all times. The pump is usually controlled by a vacuum regulator which operates the pump to maintain the vacuum within limits and operates in response to a pressure difference between the atmosphere and the return to control the vacuum in the return main. The source of steam supply hiay be a low pressure boiler as shown in Fig. .12, or a high . 274 Fig. 11. Typical Installation Using Condensation Pump ward slope. In some instances local conditions make it necessary to drop the return below the level of the vacuum pump inlet, before the pump can be reached. In such an event one of the advantages of the vacuum system is the ability to raise the condensate to a considerable height by the suction of the vacuum pump by means of a lift, connection or fitting inserted in the return. The height the condensate can be raised depends on the steam pressure and the amount of vacuum maintained.. It is preferable to limit lift connections to a single lift at the vacuum-pump- A ' still more preferable arrangement is the use of an accumulator tank, :pr receiver tank with a float control for the pump, at the low point of the return main located adjacent to the vacuum pump- When the vertical lift is considerable, several lift fittings should be used in steps as shown in Fig. 13. This permits a given lift to be secured with a somewhat lower vacuum than where the vertical distance is served by . a single lift. Where several lifts are present in a given system at different . 275 i "i\ HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 15. STEAM HEATINC SYSTEMS \ > 'it locations, the lifting cannot occur until the entire system is filled with varying the pressure, temperature and volume of steam in circulation. i.. steam. A lift connection for location close to the pump, where the size These systems differ from the ordinary vacuum system in that they main may be above the commercial' stock sizes, is shown in Fig. 14. It- is tain a controllable partial vacuum on both the supply and return sides of desirable that means be provided for manually draining the low point of ' the system, instead of only on the return side. In the vacuum system* the lift fittings to eliminate from the return piping all water in danger of steam pressure above that of the atmosphere exists in the supply-mains freezing-in case the system is shut down for a considerable length of time. and radiators practically at all times. In the sub-atmospheric system, atmospheric pressure or higher exists in the steam supply piping and Down-Feed Vacuum System ' radiators only during severe weather. Under average winter temperature . The piping arrangement for the down-feed vacuum system is similar on the. supply side to the down-feed vapor system in that it has similar runouts, radiator valves, drips on the bottom of the steam drops, andenlargement of the drops for the lower radiator connections. The return the steam is under partial vacuum which in mild weather may reach as high as 25 in. Hg., after which further reduction in heat output is obtained by restricting the quantity of steam. . The rate of steam supply is controlled by a valve in the steam main or by thermostatically controlling the rate of steam production in the boiler. 'sid'e of the" system is exactly the same"as the up-feed system except that the steam-riser-drips at the bottom are'connected into the 'return line through thermostatic traps. It is preferable to take the runouts for the risers from the bottom or at a 45-deg angle down from the steam main so that they may serve as steam main drips. When this is done.it is practical to run the steam maim level if a runout is located at every-change in pipe'size, or if eccentric fittings are used (Fig. 15). A slight pitch in the steam main, however, should be used when possible. An overhead vacuum down-feed system is shown diagrammatically in Fig. 16. , SUB-ATMOSPHERIC SYSTEMS / i Sub-atmospheric systems are similar to vacuum systems but, in con>trast,; provide control of building temperature by variation of the heat output1 from the radiators. The radiator heat, emission is controlled by &76 Fig. 13. Method of Making Lifts on Vacuum Systems, when Distance is Over 5 ft Fig. 14. Detail of Main Return Lift at Vacuum Pump '! ECCENTRIC SEDUCING . ICOUPUNQ.. Fig. 15. == Method of Changing Size of Steam Main when Runouts are Taken from Top The control -valve may be of the automatic modulating or floating type governed thermostatically from selected "control points in the building or it may be a special pressure reducing valve which will maintain the; desired sub-atmospheric pressures by continuous flow into the heating main. All radiator supply Valves have incorporated adjustable orifices or are equipped with regulating orifice plates. The sizes of orifices used are larger, than for orifice systems because for equal radiator sizes the volume flowing is larger. These'orifices are . omitted on some systems, depending upon the type of control. Radiator traps and drips are designed to operate at any pressure from 15 lb gage to 26 in. of Hg. A vacuum pump capable of, operating at high vacuum is preferable to promote accuracy in the distribution of steam throughout the system, particularly in mild weather. This vacuum is partially self induced, by the condensation of the steam in the system under conditions of restricted supply for reduction of the radiator heat emission.' 277 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 The returns must grade downward constantly and uninterruptedly from the radiator, return outlets to the.inlet of the receiver of the.vacuum pump. One radical difference between this and the .ordinary vacuum system is that no lifts should be made in the return, line,, except at the vacuum pump. The receivers are placed at, a lower level than the pump and equipped with float control so the pump may. operate as a return pump Under night conditions. The system may be operated in the same manner .1: ! as the ordinary vacuum system when desired. . . ' Steam for heating domestic hot water should be taken from the boiler header back of the control valve so that pressures sufficiently high for heating the water may be maintained on the heater. Thetsub-atmpspheric method of heating can be used for the heating coils of ventilating and air conditioning systems.. The flexible control of heat, output secured by this method materially reduces the required size of by-pass around the heaters. Sub-atmospheric systems are proprietary. ORIFICE SYSTEMS Orifice systems of steam heating may have piping arrangements identi cal with vacuum systems. Some of these omit the radiator thermostatic traps but use thermostatic or combination float and thermostatic traps on all drip points. A return condensation pump, with receiver vented to atmosphere, a return line vacuum pump, or a return .trap, is.generally used to return the condensation to the boiler or place of similar disposition, 11 278 CHAPTER 15. STEAM HEATING SYSTEMS such as a feed-water heater or hot well. The heat emission from the radiators is controlled by varying the pressure maintained in the steam supply piping. The principle on which these systems operate is based on the fact that the steam flow through an orifice will vary when the ratio of the absolute pressures on the two sides of the orifice exceeds 58 per cent. If the abso lute pressure on the outlet side is less than 58 per cent of the absolute pressure on the inlet side, no further increase in flow will be obtained as a result of the increased pressure difference. If an orifice.is so designed in size as to exactly fill a radiator with 2 lb gage on one side and 34 lb gage on the other, the absolute pressure relation is: 14 7 4- 0 24 7 _|_ 2 0 = 0 9 or 90 Per cent- Should the steam pressure be dropped to 34 lb on the supply pipe, the pressure on each side of the orifice would be balanced and no steam flow would take place. -From this it will be apparent-that if an orifice of a given diameter will fill a given radiator with steam when there is a given pressure on the main, reducing this steam main pressure will permit filling various desired portion of the radiator down to the point where the main pressure equals the back pressure in the radiator provided the supply pipe pressures may be controlled sufficiently close. If orifices are designed on a similar basis for a given system and proportioned to the heating capacity of the radiators they serve, all radiators will heat proportionately to the steam pressure. The range of pressure variation is limited by the per missible noise level of the steam flowing under the pressure difference required for maximum heat output. The control of the steam supply is obtained by a valve placed in the steam main, which maintains a deter mined pressure; or by a boiler pressure control. The valves are frequently manually set from a remote location, guided by temperature indicating stations in the building; or thermostatically controlled from a thermostat on the roof, which automatically measures the differential of outside and inside temperatures. Since the range through which the pressures may be varied is usually from 0 to 4.0 lb gage,, the control should be capable of maintaining close regulation to maintain the desired space temperatures, particularly in mild weather. Some systems use orifices not only in radiator inlets but also at different points in the steam supply piping for the purpose of balancing the system to a greater extent. In this manner the difference between the initial and terminal pressure in the steam main may be compensated to a great extent. For example, if the initial pressure was 3 lb gage and the pressure at the end of the main was 2 lb, an orifice could be used in each branch for the purpose of obtaining a more uniform pressure throughout the system. Such a provision may be particularly useful in this system for branches close to the boiler where the drop in'the main has not yet been,produced. Orifice systems are proprietary. .. , ZONE CONTROL Often certain portions of a building may require more heat than others even if occupied for the same daily periods and the same maintained 279 HEATING VENTILATINC AIR CONDITIONING CUIDE 1940 CHAPTER 15. STEAM HEATING SYSTEMS temperatures exist. Sometimes an entire building is on one general under the existing static head. The return of the condensate permits the control, which results in overheating some sections when sufficient heat is water to repeatedly go through the cycle of vaporization, with subsequent supplied to accommodate the coldest portion. . condensation and return to the boiler. During such repeated cycles any By separating a building into zones, each with its own piping system, each zone may be controlled separately. Systems are zoned to care for ex incrustants or other substances in solution are precipitated and the water de-activated to a considerable extent so that corrosion of a serious nature posure, hours of occupancy, stack effect and the requirements of occu pancy activity. . , In large buildings it is important to consider zoning for exposure because of the varying effects of the wind and sun. With the prevailing is seldom ever encountered where the condensate is repeatedly used. Serious corrosion is more frequently found in systems where the conden sation is not repeatedly used but is wasted and fresh make-up water is continually being introduced. winter winds from the northwest, for example, a simple zoning would place the north and west sides of the building on one zone and the south and east sides on another. If the size of the building justifies the expendi The most generally accepted condensation pump unit for low pressure heating systems consists of a motor-driven centrifugal pump with receiver and automatic float control. Other types in use include rotary, screw ture, a better arrangement would be to place all north walls on one zone, all west walls on a second, all east walls on a third, and all south walls on a and reciprocating pumps with steam turbine or motor drive, and directacting steam reciprocating pumps. fourth. Certain interior areas, such as basements, light well walls and other The receiver capacities of these automatic units should be sized so as locations where sun and wind do not affect the conditions, should be placed { in still another zone if the most economical operation is to be secured. not to cause too great a fluctuation of the boiler, water line if fed directly to the boiler and at the same time not so small as to cause too frequent In high buildings it is often important to consider zoning for stack or operation of the unit. The usual unit provides storage capacity between chimney effect, caused by the difference in density between the warm air on the inside of a building and the colder air on the outside. Where the lowest eight or ten stories are protected from winds by surrounding buildings, it may accentuate the need for zoning to correct for the chimney ' stops in the receiver of approximately 1.5 times the amount of condensate returned per minute and the pump generally has a delivery rate of 3 to 4 times the normal flow. This relation of receiver and pump size to heating system condensing capacity takes account of the peak condensation rate; effect. On still days the heat demands vertically will vary little, but on windy days there will be a marked difference in the heat requirements for the different horizontal sections at different elevations. An arrangement to provide for difference in heat requirement for exposure and chimney effect would give 12 zones; namely, north, east, south, and west lower zones; similar middle zones; and similar top zones. Every type of steam heating system may be zoned. The extent to which any system may be zoned is governed by the limitations of the given installation and the particular type of system. Zone control is used principally with sub- atmospheric, orifice and vacuum heating systems- .. _ Each zone should constitute an individual and separate system with its own control valve (controlled by thermostats in its respective zone); steam supply and return piping and preferably its own return pump of vacuum pump. It is possible for a single vacuum pump to serve several zones with- a.Controller for each section connected in parallel so:that the zone in which the.lowest differential or vacuum is produced may start the pump. . . ....................... ; Zoning has advantages even where individual thermostatic radiator control is installed, whether this be of pneumatic, electric, or the selfcontained radiator valve type. The control secured by zoning in supply ing heat in parallel with its outside temperature and wind fluctuations removes a large part of the load from such individual thermostatic controls; they operate less frequently and the radiators follow a more even temperature. ' VACUUM HEATING PUMPS On vacuum systems, where the returns are under a vacuum, and sub- atmospheric systems, where the supply piping, radiation and the returns are under a vacuum, it is necessary to use a vacuum pump to discharge the air and non-condensable gases to atmosphere and to dispose of the condensation. Direct-acting steam driven reciprocating vacuum pumps are sometimes used where high pressure steam is available or where the exhaust steam from the pump can be utilized. In general, however, these have been replaced by the automatic motor-driven return line heating pump especially developed for this service. Steam turbine drive is .also frequently used where steam at suitable pressures is available, the steam being used afterward for building heating. The usual vacuum pump unit consists of;a compact assembly of exhausting unit for withdrawing the air-vapor mixture and discharging the air to atmosphere arid a water removal unit which discharges the condensate to the boiler. They are furnished complete with, receiver, separating tank and automatic controls mounted as an integrated unit on one.base. There.are also special steam turbine driven units,which are'operated by passing the steam to be used in heating the building through the turbine with only a 2 to 3 lb drop across the turbine required for its operation, Under special, conditions such as installations where it is necessary to return the condensate to a high pressure boiler, auxiliary water pumps may be supplied. In some instances separate air and water pumps may be used. . CONDENSATION RETURN PUMPS Condensation return pumps are used for gravity systems when the local conditions do.not permit the condensation to return to the boiler Practically all automatic motor-driven return line vacuum heating pumps make use of a portion of the condensate to operate either as a liquid piston pump or as a kinetic exhauster (which operate on a modified ejector principle) to withdraw the air arid condensate from the system, 280 . 281 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 discharge the air to atmosphere and return the condensate to the boiler. Some type of hydraulic action is utilized to produce the suction. Such hydraulic evacuating devices may be classified as: a. Water ring centrifugal displacement pumps. b. Water piston pumps. : . c. Stationary kinetic exhauster .pumps.. -. d. Rotary kinetic ejector pumps. . , , '` The-evacuating element is generally combined with a centrifugal water impeller for the delivery of the condensate to the boiler or feed water heater. ; -. . .. The assembled units may be further grouped under two general classifications: a. Those which perform the function of air separation under atmospheric pressure. b. Those which perform the function of air separation under a partial vacuum. Pumps coming under the first classification remove both the air and condensate from the returns by means of the hydraulic- evacuator and deliver both to a separating tank under atmospheric pressure. From this tank the air and non-condensable vapors are vented to atmosphere while the condensate is removed and delivered to the boiler by means of the built-in boiler feed pump impeller. In the second classification, the air and condensate are first separated under vacuum by means of the receiver which is directly connected to the returns. The hydraulic evacuator withdraws only the air and non condensable vapors from the. top of the receiver and delivers them to atmosphere. The built-in condensate pump impeller removes the con densate from the bottom of the receiver and delivers it direct to the boiler or feed-water heater. . Under special conditions such as returning-the condensate to a high pressure boiler or the furnishing of large air removal units for high vacuum systems, it is customary to supply separate motor-driven air and water pumps. -- For rating purposes1 vacuum pumps are classified as low vacuum and high vacuum. Low vacuum pumps are those rated for maintaining 5}4 in. Hg. vacuum on the system, and high vacuum pumps are those rated to maintain vacuums above 534 in-- , The vacuum that can be maintained on a system depends upon the relationship of the air leakage rate into the system to the operating air capacity of the hydraulic evacuator when operating at any given return line temperature. The hotter the returns, the lower will be the possible vacuum for a given air leakage rate into the system. It is particularly essential on high vacuum installations To see that the entire system is tight in order to reduce the amount of inward air leakage and, further more, to see that relatively higher temperature steam is prevented from entering the vacuum return lines through leaky traps, high pressure `A.S.H V.E. Standard Code for Testing and Rating Return Line Low Vacuum Heating Pumps, (A.S. H-V.E. Transactions, Vol. 40, 1934. p. 33). - 282 CHAPTER 15. STEAM HEATING SYSTEMS V drips, etc. It is for this reason that the condensate from equipment using steam at high pressures should not be connected directly to a vacuum return line but should drain to a receiver through a high pressure trap. The receiver should have an equalizing connection to a low pressure steam main and drain through a low pressure trap to the vacuum return main as indicated in Fig. 17. . :; - . Vacuum Pump Controls , In the ordinary vacuum system, the vacuum pump is controlled by a vacuum regulator'which cuts in when the vacuum drops to the lowest point desired and cuts out when it has been increased to theTiighest point, these points being varied to suit the particular system* or operating conditions.. In addition to this vacuum control, a float control is included Fig. 17. . Method of Discharging High-Pressure Apparatus into Low-Pressuhe ; ' Heating Mains and Vacuum Return Mains through ; ` 1 a Low-Pressure Trap which wiH aiitoma.tica.lly start the pump whenever sufficient condensation accumulates in the receiver, regardless of the vacuum on the'system. A selector switch is usually provided to allow operation at night as a con densation piiinp' only5, also to give manual or continuous operation, when desired'. .4 ! ' ' . -' ; ; ' '/ : . 4 There are several variations in the' control of the vacuum maintainedloti the system by the pump. In' some sub-atmospheric systems where orifices are used, the vacuum pump control maintains a pressure difference between'the supplyarid the return piping,.which is held within relatively close limits.: There are other- - sub-atmospheric systems^which utilize special temperature-pressure actuatedcontrols for maintaining the desired conditions in the return lines. - Where'various zones are connected to the same return main, the return vacuum must be controlled to meet the requirements of the zone operating at the lowest steam supply'pressure. Piston Displacement Vacuum Pumps ' .. , Piston displacement return vacuum heating pumps may be'either'electric or steam driven. They should be provided with mechanical lubricators 283 I I II HEATING VENTILATING AIR CONDITIONING GUIDE 1940 and their piston speed in feet per minute should not exceed 20 times the square root of the number of inches in their stroke. They are usually supplied with an air separating tank, open to'atmosphere, placed-on the discharge side of the pump and at an elevation sufficiently high to allow ' gravity flow of the condensate to the boiler. If the boiler pressure is too high for such gravity feed then an additional steam pump for feeding the boiler is desirable. The extra pump is sometimes avoided by using a closed separating tank with a float controlled vent. In both arrangements, the air taken from the system must be discharged against the, full dis charge pressure of the vacuum pump.' In the case of highor medium pressure boilers, it is better, to use the atmospheric separator and the second pump. . In figuring the required displacement for such pumps; a value of from 6 to 10 times the volumetric flow of condensation is used for average vacuums and systems. TRAPS Traps are generally classified as to function as (a) separating traps, (6) return, lifting or vacuum traps, and (c) air traps. Separating traps may be either float operated, thermostatically operated or float and thermostatically operated. Return traps for low pressure service are referred to later as alternating receivers in this chapter. Return traps may also operate to receive condensate under a vacuum and return it to atmosphere or a higher pressure.. Air traps are generally float operated. Separating traps are used to release water of condensation but to retain steam. The thermostatic, and float and thermostatic types release, both condensate and air but retain steam. Separating traps are used for draining condensate from radiators, indirect air heaters, steam piping systems, kitchen equipment, laundry equipment, hospital equipment, drying equipment and many other kinds of apparatus. Air traps release air but retain water. Devices known as air ventsare, in principle, traps which allow the passage of air but prevent the passage of either water or steam. - " - : : . ' .. ,' Return traps are used for returning condensate either-by gravity, by steam pressure, or by both, to a boiler or other point of disposal, and for lifting condensate from a lower to a higher elevation, or for handling condensate from a lower to a higher pressure. . .. ; The fundamental principle upon which the operation of practically all traps depends is that the pressure within the trap at the time of discharge shall be equal to, or slightly in excess of, the pressure against which the trap must discharge; including the friction head, velocity head and static head on the discharge side of the trap. If the static head is in favor of the trap discharge it is a minus quantity and may be deducted from the other factors of the discharge head. -. ; Traps may also be classified according to the principle of operating device which supplies the power to cause them to function as (1) float, (2) bucket, (3) thermostatic, (4). float and thermostatic, (5) impulse, or (6) tilting traps. . ' . ., . 284 CHAPTER 15. STEAM HEATING SYSTEMS Float Traps. A discharge valve is operated by the rise and fall of a float due to the change of water level in the trap. When the trap is empty the float is in its lowest position, a'ad the discharge valve is closed. A gage glass indicates the height of water . in the chamber. . .. ... - -. - Unless float traps are well made and proportioned there is danger of considerable steam leakage through. the discharge valve due to unequal expansion of the valve and seat and the sticking of moving parts. The discharge from a float trap is usually con tinuous since the height of the float, and consequently the area of the outlet, is propor tional to the amount of, water present. .; Backet Traps. Bucket traps are of two types, the upright and inverted, and although they are both of the open float construction, their operating principle is entirely different. In the upright bucket trap, the water of condensation enters the trap and fills the space between the bucket and the walls of the trap. This causes the bucket to float and forces the valve against its seat, the valve and its stem usually being fastened to the bucket. When the water rises above the edges of the bucket it flows into it and causes it to sink, thereby withdrawing the valve from its seat. This permits the steam pressure acting on the surface of the water in the bucket to force the water to a discharge opening. When the bucket is emptied it rises and closes the valve and another cycle begins. The discharge from this type of trap is intermittent. In the inverted bucket trap, steam floats the inverted submerged bucket and closes the valve. Water entering the trap fills the bucket which sinks and through compound leverage opens the valve, and the trap discharges. It is impossible to install a water gage glass on an inverted bucket trap, but if visual inspection is necessary, a gage glass can be placed on the line leading to the trap. No air relief cocks can be used, but this is unnecessary, as the elimination of air is automatically taken care of by air passing through the vent in the top of the inverted bucket regardless of temperature. Thermostatic Traps. Thermostatic traps are of two types, those in which the discharge valve is operated by the relative expansion of metals, and those in which the action of a volatile liquid is utilized for this purpose. Thermostatic traps of large capacity for draining blast coils or very large radiators are called blast traps. Float and thermostatic traps have both a thermostatic element to release air and a float element to release the water. Impulse traps operate with a moving valve actuated by a control cylinder. When the trap is handling condensate, the pressure required to lift the valve is greater than the reduced pressure in the control cylinder and consequently the valve opens allowing a free discharge of condensate. As the remaining condensate approaches steam tempera ture, flashing results, flow through the valve orifice is choked and the pressure builds up in the control chamber closing the valve. Automatic Return Traps In the general heating plant, where thermostatic traps are installed on the heating units, it becomes necessary to provide a means for returning the water of condensation to the boiler, if a condensation or vacuum pump is not used. When the return main can be kept sufficiently high above the boiler water line for all operating conditions, the water of condensation will flow back by gravity, and no mechanical device is required; But actually this does not work out in practice. It follows, therefore, that a direct-return trap is needed for the handling of the condensation even though it may not be called into action except under some operating condition where the pressure differential exceeds the static head provided. The installation of a direct-return trap assures safety for such systems; and guarantees the operation of the plant under varying conditions. Automatic return traps, sometimes called alternating receivers, may be of the counter-balanced, tilting type, or spring actuated. These consist of a small receiver with an internal float, and when the condensate will not flow into the boiler under pressure, it will feed into the receiver of the 285 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 j trap, and in so doing, raise or tilt the float or mechanism which actuates a j steam valve/automatirally. This admits steam to the receiver, at boiler } pressure, and the equalizing of the pressures which follows allows the f water to .flow intp the boiler.. . , . j : Tilting. Trip's.`With this type of trap, water enters a bowl and rises until its weight ; overbalances that! of a counter-weight, and the bowl sinks to the bottom. As the bowl ; sinks, a valve is opened thus admitting' live' steam pressure on the surface of the water j and the trap then discharges. After the water is discharged, the counter-weight sinks and raises the bowl, which in turn closes the valve and the cycle .begins again. Tilting 11 traps are necessarily intermittent in operations They are not ordinarily equipped with ; - glass water gages, as the action of the trap shows when it is filling or emptying. The air (j relief of tiltmg traps is taken care of by the valves of the trap. i [ ' ' 1 : l\ - . . ', v: . ' ... . : ; , 1 a 286 Chapter 16 PIPING FOR STEAM HEATING SYSTEMS Operating Characteristics, Steam Flow, Pipe Sizes, Tables for Pipe Sizing, One-Pipe Gravity Air-Vent Systems, Two-Pipe Gravity Air-Vent Systems, Two-Pipe Vapor Systems, Vacuum, Orifice, Atmospheric and Sub-Atmospheric Systems, Boiler and Radiator Connections, Piping for Indirect Heating Units, Dripping IT is important that steam piping systems distribute steam not only at full design load but during excess and partial loads. Usually the average winter steam demand is less than half of the demand at the design outside temperature. Moreover, in rapidly warming up a system even in moderate weather, the load on the steam main and returns may exceed the maximum operating load for severe weather due to the neces- sity of raising the temperature of the metal in the.system to the steam temperature and the building to the design indoor temperature. Investi gations of the return of condensation have revealed that as high as 143 per cent of the design condensation rate may exist under conditions of actual operation. The functions of the piping system are the distribution of the steam, the return of the condensate and in systems where no local air vents are provided, the removal of the air. The distribution of the steam should be rapid, uniform and without noise, and the release of air should be facili tated as much a:s possible, as an ait bound system will not heat readily nor properly. In designing the piping arrangement it is. desirable to maintain equivalent resistances in the supply and return piping to and from a radiator.. Arranging the piping so the total distance from the boiler to the radiation is the same as the return piping distance from the heating unit back to the boiler,tends to obtain such a result. The condensation which occurs in steam piping as well as in radiators must be drained to prevent impeding the ready flow of the steam and air. The effect of back pressure in the returns, and excessive revaporization such as occurs where condensation is released from pressures considerably higher than the vacuum or pressure in the return, must be avoided. The piping design of a. heating system is greatly influenced by its operating chracteristics. Heating systems do not operate under constant conditions as they are continually changing due .to variation, in load. As the system is being filled with steam the .pressure existing in various 287 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 ____________________ Table 1, Flow of Steam in Pipes P -- loss in pressure in pounds. d = inside diameter of pipe in inches. L = length of pipe in feet. D = weight of 1 cu ft of steam. W = pounds of steam per hour. W = 5220 P = 0.0000000367 ( 1 + Pressure Loss IN Ounces Col. 1 Pipe Size Actual s/iuV Nomina Internal io Diameter - Pipe Sq Inches Col. 2 7 d> ST Gage Col. 3 /-- V0 or Pipb IN Feet Col. 4 v? 0.25 65.28 i 1.049 0.864 0.536 -- 1.0a 0.187 20 2.240 0.50 92.28 t(9o 1 1.380 1.496 1.178 0.190 40 1.580 1.00 130.5 i 'A . 1.610 2.036 1.828 0.0 0.193 60 1.290 2 184.6 2 2.067 3.356 3.710 . 0.3 0.195 80 1.120 3 226.0 2K 2.469 4.788 6.109 1.3 .0.201 100 1.000 4 261.0 3 3.068 7.393 11.183 2.3 0.207 120 0.912 5 291.8 m 3.548 9.8?7 16.705 5.3 0.223 140 0.841 6 319.7 4 4.026 12.730 23.631 10.3 0.248 .160 0.793 7 345.3 4.506 15.947 32.134 15.3 0.270 180 0.741 8 369.1 5 5.Q47 20.006 .43.719 20.3 0.290 200 0.710 10 412.7 6 6.065 28.886 . 71'. 762 30.3 0.326 250 0.632 12 452.0 7 7.023 38.743. 106.278 40.3 0.358 . 300 0.578 14 488.3 8 7.981 50.027 149.382 50-.-3- .0.388 350 0.538 . 16 . 522.0 9 8.941 62.786 201.833 60.3 0.4i5 :. 400. 0.500 20 583.6 10 10.020 78.854 272.592 75.3 0.452 450 > 0.477 .24 . 639.3 12 , 12.000 113.098, .437.503 100,3 0.507 500 0.447 28 . 690.5 14 13.250 . 137,880 566.693 125.3 0.557 . 600 0.407 32 738.2 16 15.250 182.655 816.872 150.3 0.603 700 0.378 . 40 48 80 160 320 480 825.4 904.1 1167.2 1650.7 2334.5. 2859.1 Column I X 2 X3 X 4 lb of steam 175.3 0.645 pipe for a given condition. 200.3 Example I: I oz drop -- 2 in. pipe -- 1.3 lb press. -- 100 ft equivalent length: 0.685 130.5 X 3.710 X 0.201 X 1 97.2 lb per hour. 97.2 X 4b 388.8 sq ft equivalent radiation. T Table 1 does not aUow for.entrained water.in low-pressure steam, condensation in covered pipe and roughness in com- mercial pipe as found uvpractice 800 900 1000 1200 1500 2000 0.354 0.333 0.316 0.289 0.258 0.224 Pounds per square inch gage => 2.04 in. Vacuum. Mercury Column. - The factor 4 is the approximate equivalent in square feet of steam radiation of 1 lb of steam per hour. 288 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS locations may be different than those which exist for appreciable periods at other locations and which under constant pressure may have conditions that are approximately the same. In designing piping it is of especial imporance to arrange the system to preclude trouble caused by such nressure differences. The systems, which readily release the air permit uniform pressures to be attained in much shorter time intervals than those which are sluggish. Results are given in Fig. 1 from investigations1 to determine the rate of condensate and air return from a two-pipe gravity heating system. Variations in the steam pressure during the warming up period when the rate of air elimination and condensation is high are clearly indicated in these curves. .- . - It is evident that the condensation flow during the initial w;arming up Fig. 1. Relation* Between Elapsed Time, Steam Pressure, Condensate and Air Elimination Rates . ;' period reaches a peak which' is greater than the constant condensation rate which is eventually reached when the pressure becomes uniform. Moreover, the peak condensation rate is obtained when the system steam pressure is lower than that existing during a period of constant condensing rate. It will also be noted that the peak rate of air elimination does not coincide with the higher condensing rate. STEAM FLOW The rate of flow of dry steam or steam with a small amount of water flowing in the same direction is in accordance with the general laws of gas flow and is a function of the length and diameter of the, pipe, the density of the steam, and the pressure drop through the pipe. This relationship has been established by Babcock in the formula given at the top of Table 1. In Columns 1, 2, 3, and 4 of this table, the numerical values of the factors for different pressure losses, pipe diameters, steam densities and lengths of pipe have been worked out in convenient form so that the steam flowing in any pipe may be calculated by multiplying together the proper factors in each column as shown in the example at the bottom of the table. `A.S-H.V.E. Research Report No. 954--Condensate and Air Return in Steam Heating Systems, by F. C. Houghten and J. L. Blackshaw (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 199). ' 289 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 PIPE SIZES The determination of pipe sizes for a given load in steam heating depends on the following principal factors: 1. The initial pressure and the total pressure drop which may be allowed between the source of supply and the end of the return system. ; 2. The maximum velocity of steam allowable for quiet and dependable operation of the system, taking into consideration the direction of condensate flow. 3. The equivalent length of the run from the boiler or source of steam supply to the farthest heating unit. - Initial Pressure and Pressure Drop Theoretically there are several factors to be considered, such as initial pressure and pressure required at the end of the line, but it is most im portant that (1) the total pressure drop does not exceed the initial pressure of the system; (2) the pressure drop is not so great as to cause excessive velocities; (3) there is a constant initial pressure, except on systems specially designed for varying initial pressures, such as the sub-atmos pheric which normally operate under controlled, partial vacua, the orifice, and the vapor systems which at times operate under such partial vacua as may be obtained due to the condition of the fire; and (4) the equivalent head due to pressure drop does not exceed the difference in level, for gravity return systems, between the lowest point on the steam main, the heating units, or the dry return, and the boiler water line. All systems should be designed for a low initial pressure and a reason ably small pressure drop for two reasons: first, the present tendency in steam heating unmistakably points toward a constant lowering of pres sures even to those below atmospheric; second, a system designed in this manner will operate under higher pressures without difficulty. When a system designed for a relatively high initial pressure and a relatively high pressure drop is operated at a lower pressure, it is likely to be noisy and have poor circulation. . ,, . The total pressure drop should never exceed one-half of the initial pressure when condensate is flowing in the same direction as the steam. Where the condensate must flow counter to the steam, the governing factor is the velocity permissible without interfering with the condensate flow. A.S.H.V.E. Research Laboratory experiments limit this to the capacities given in Tables 2 and 3 for. Vertical risers and in Table 4 for horizontal pipes at varying grades. Maximum Velocity The capacity of a steam pipe in any part of a steam system depends upon the quantity of condensation present, the direction in which the condensate is flowing, and the pressure drop in the pipe. Where the quantity of condensate is limited and is flowing in the same direction as the steam, only the pressure drop need be considered. When the con densate must flow against the steam, even in limited quantity, the ve locity of the steam must not exceed limits above which the disturbance between the steam and the counter-flowing water may produce object ionable sounds, such as water hammer, or may result in the retention of water in certain parts of the system until the steam flow is reduced 290 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS Table 2. 1* ' Maximum Allowable Capacities of Up-Feed Risers for One-Pipe Low Pressure Steam Based on A. S. H. V. E. Research Laboratory Tests ; Pips Sizb iNCHBB Velocity Feet Pee Second Pressure Drop Ounces = per 100 Ft A i ~~ m IX "" 2 2A 33A 4 B 14.1 17:6 20.0 23.0 26.0 29.0 31.0 32.0 C 0.68 0.66 0.66 0.57 0.54 0.48 0.44 0.39 So Ft Radiation D- . 45 98 152 288 464 799 1144 1520 . Capacity'' Btaper Hour E 10.961 23,765 36,860 69,840 112,520 193,600 .277,000 368,000 . Lb Steam per Hour F ll.:3 24.5 38.0 . . 72:0 116.0 199.8 286.0 380.0 INSTRUCTIONS FOR USING TABLE 2 1. Capacities given in Table 2 should never be exceeded on one-pipe risers. 2. Capacities are based on &-lb condensation per square foot equivalent radiation and actual diameter of standard pipe. . 3. All pipe should be well reamed and free from constrictions. Fittings should be up to size. (See Tables 5 and 6). . Table 3. Maximum Allowable Capacities of Up-Feed Risers for Two-Pipe . Low Pressure Steam :. Based on A. S. H. V. E. Research Laboratory Tests Pipe Sob Inches Velocity Feet per Second Pressure Drop Ounces per 100 Ft A . .. B -- C H 20 l 23 -- 1.78 27 1.57 lA 30 1.48 2 - 35 1.33 VA 38 . 1.16 3 41 0.95 3A 42 0.81 4 43 0.71 Sq Ft Radiation D 40 74 151 228 438 678 1129 1548 2042 Capacity Btu per Hour Lb Steam per Hour .E 9,550 F 10.0 17,900 36,500 55,200 106,100 164,100 273,500 375,500 495,000 ' 18.45 37.65 57.0 109.5 169.4 282.2 387.0 510.5 INSTRUCTIONS FOR USING TABLE 3 1. The capacities given in this table should never be exceeded on two-pipe risers. ' 2. Capacities are based on }-\b condensation per square foot equivalent radiation and actual diameter of standard pipe. - 3. Ail pipe should be well reamed and free from constrictions. Fittings should be up to size. (See Tables 5 and 6.) 291 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 sufficiently to permit the water to pass. The velocity at which such disturbances take place is a function of (1) the pipe size, whether the pipe runs horizontally or vertically, (2) the pitch of the pipe if it runs hori zontally, (3) the quantity of condensate flowing against the steam, and (4) freedom of the piping from water pockets which under certain con ditions act as a restriction in pipe size. ' | Three factors of uncertainty always exist in determining the capacity of any steam pipe. The first is variation in manufacture, which appar ently cannot; be avoided and which caused an actual difference of 20 per cent in the capacity of a 1-in. pipe in experiments carried on at the A.S.H.V.E. Research Laboratory (Table 5). The second is the reaming of the ends of the pipe after cutting, which, experiments indicate, might reduce the capacity of a 1-in. pipe as much as 28.7 per cent (Table 6). The third is the uniformity in grading the pipe line. All of the capacity . tables given in this chapter include a factor of safety. However, the pipe Table' 4.' Comparative Capacity of Steam Lines at Various Pitches for Steam .... . ........ and Condensate Flowing in Opposite Directions3 . .. ' Pitch of Pipe in Inches per 10 Ft , Pitch or PtPB y, in. H . 1 IN. 1M ni. 2 ra. ' 3 m. 4 m. 5 IN. Pipe Size > si s' laches SqFt Rad. Based on 240 Btu Sq Ft Rad. a 2 Based on 240 Btu i rs SqFt Rad. Based on 240 Btu > 3 S ,8q Ft Rad. -Based on 240 Btu ' a Sq Ft Rad. Based on 240 Btu 1 i2 Sq Ft Rad. Baaed on 240 Btu $ a 2 Sq-Ft Rad. Baaed on 240 a Btu 2 SqFt rad. Based on 240 *s.. > - Mea . Btu ' 2 H IK IK 25.0 45.8 104.9 142.6 236.0 12 12 18 18 19 30.3 52.6 117.2. 159.0 263.5 14 15 20 21 20 37.3 63.0 133.0 181.0 299.5 18 17 23 23 23 .40.4 70.0 144.5 196.5 325.5 19 20 25 25 25 42.5 20 s 46.1 75.2 22 83.0 154.0 .27 165.0 209.3 27 224;o 346.5 27 371.5 21 23 28 28 28 47.5 87.9 172.6 234.8 388.4 22 25 29 30 29 178.2 242.6 401.1 30 Data from American Society of Heating and Ventilatinc Engineers Research Laboratory. on which Table 5 is based showed no particular defects or constrictions on the inside, and the factor of safety referred to does not cover abnormal defects or constrictions nor does il cover pipe not properly reamed. Equivalent Length of Run All tables for the flow of steam in pipes, based on pressure drop, must allow for the friction offered by the pipe as well as for the additional resistance of the fittings and valves. These resistances generally are stated in terms of straight pipe; in other words, a'certain fitting will produce a drop in pressure equivalent to so many feet of straight run of ' the same size of pipe. Table 7 gives the number of feet of straight pipe usually allowed for the more common types of fittings and valves. In all pipe sizing tables in this chapter the length of run refers to the equivalent length of run as distinguished from the actual length of pipe in feet. The length of run is not usually known at the outset; hence it is necessary to assume some pipe size at the start. Such an assumption frequently is considerably in error and a niore common and practical method is to assume the length of run and to check this assumption after the pipes are sized. For this purpose the length of run usually is taken as double the actual length of pipe. . 292 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS t ,, k Per Cent Difference in Capacity for'Carrying Steam and Condensate tabled. . due TO Variation of Pipe Size and Smoothness3 Maximum Condensation. Lb per Hour Size of pipe--------- ------ Minimum--------- ------ -- Maximum------------------- per cent variation------ Min. 14.00 15.20 8.6 1 In. 24.89 30.08 20.8 .. 1M In45.42 52.08 14.7 min. 70.50 . 82.00 16.3 = Data from American Society of Heating and Ventilating Engineers Research Laboratory.' Table 6. Effect of Reaming Entrance to One-Inch One-Pipe Risers3 Maximum Capacitt or Riser 24.7 lb per hour 23.9 lb per hour 22.2 lb per hour 19.2 lb per hour 17.6 lb per hour ' Pee Cent Decrease 0.0 3.2. io:i 22.2 28.7 ' Data from American Society of Heating and Ventilating Engineers Research Laboratory. TablI 7. . .. Length in Feet of Pipe to be Added to Actual Length of Run-- . Owing to Fittings--to Obtain Equivalent. Length Size of Pipe . Inches St'd. Elbow Side Outlet Tee Gate Valve | Globe Valve Ancle Valve . Length in Feet to be Added to Run 2 m 3 .5 7 10 16 ...2 .. 18 9 .. 20 3 25 12 =. 26 3 33 .16 3M ; 12 4 14 31 35 4 39 .19 5 45 22 5 18 44 7 57 28 6 22 50 9 70 - 32 7 26 55 10 82 37 8 31 63 12 94 42 9 35 69 13 105 47 10 12 14 39 76 47 90 53 105 15 118 18 140 20 160 52 63 72 Example of length in feet of pipe to be added to actual length of run. 152-0' MASJJEEO LEHGTH. - Bg-0 -. * SATg YALXE. S-tELBOtYS. 5 -0' . SK-O- eeumLErtT -lensth m'-o' 293 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 TABLES FOR PIPE SIZING2 Factors determining the size of a steam pipe and its allowable limit of capacity are the direction of the flow of condensate, whether against or with the steam. Tables 8 and 9 are based on the actual inside diameters of the pipe and the condensation of l/i lb (4 oz) of steam per square foot of equivalent direct radiation3 (abbreviated BDR) per hour. The drops indicated are drops in pressure per 100 ft of equivalent length of run. The pipe is assumed to be well reamed without unusual or noticeable defects. Table 8 may be used for sizing piping for steam heating systems by determining the allowable or desired pressure drop per 100 equivalent feet of run and reading from the column for that particular pressure drop. This applies to all steam mains on both one-pipe and two-pipe systems, vapor systems, and vacuum systems. Columns B to G, inclusive, are used where the steam and condensation flow in the same direction, while Columns II and I are for cases where the steam and condensation flow in opposite directions, as in risers and runouts that are not dripped. Columns J, K, and L are for one-pipe systems and cover riser, radiator valve, and vertical connection sizes,, and radiator and runout sizes, all of which are based on the critical velocities of the steam to permit the counter flow of condensation without noise. ................ - - Sizing of return piping may be done with the aid of Table 9 where pipe capacities for wet, dry, and vacuum return lines are shown for the .pressure drops per 100 ft corresponding to the drops in Table 8. It is customary to use the same pressure drop on both the steam and return sides of a system. Example 2. What pressure drop should be used for the steam piping of a system if the measured length of the longest run is 500 ft and the initial pressure is not to be over 2-lb gage? , Solution. It will be assumed, if the measured length of the longest run is 500 ft, that when the allowance for fittings is added the equivalent length of run will not exceed 1,000 ft. Then, with the pressure drop not over one half of the initial pressure, the drop could be 1 lb or less. With a pressure drop of 1 lb and a length of run of 1,000 ft, the drop per 100 ft would be Ho lb, while if the total drop were H fo, the drop per 100 ft would be Ho lb. In the first instance the pipe could be sized according to Column D for Hs lb per 100 ft, and in the second case, the pipe could be sized according to Column C for Ht lb. On completion of the sizing, the drop could be checked by taking the longest line and actually calculating the equivalent length of run from the pipe sizes determined. If the calculated drop is less than that assumed, the pipe size is all right; if it is more, it is robable that there are an unusual number of fittings involved, and either the lines must Ce straightened or the column for the next lower drop must be used and the lines resized. Ordinarily resizing will be unnecessary. ONE-PIPE GRAVITY AIR-VENT SYSTEMS One-pipe gravity air-vent systems in which the equivalent length of run . I tl does not exceed 200 ft should be sized as follows: ii JPipe size tables in this chapter have been compiled in simplified and condensed form for the convenience of the user: at the same time all of the information contained in previous editions of The Guide has been retained- Values of pressure drops, formerly expressed in ounces, are now expressed in fractions of a pound. As steam system design has materially changed in recent years so that 240 Btu ho longer expresses the heat of condensation from a square foot of radiator surface per hour, and as present day heating units have different characteristics from older forms of radiation, it is the purpose of The Guide to gradually eliminate the empirical expression square foot of equivalent direct radiation, EDR, and to substitute a logical unit based on the Btu. The new terms to express the equivalent of 1000 Btu (Mb), and 1000 Btu per hour (Mbh), have been approved by the A.S.H.V.E. 294 CHAPTER 16- PIPING FOR STEAM HEATING SYSTEMS Table 8. Steam Pipe Capacities Capacity Expressed in Square Feel of Equivalent Direct Radiation {Reference to this table will be by column letter A through L) This table is based on pipe size data developed through the research investiga tions of the American Society of Heating and Ventilating Engineers. Pips Size In. CAPACITIES OF STEAM MAINS AND RISERS DiBBcnoN or Condensation Flow in Pipe Line With tite Steam in One-Pipe and Two-Pipe Systems i/,, lb or MODrop r/a, lb or HQi Drop */is lb dr iOs Drop lb or 20s Drop Klb or 4 Os Drop ' H~lb ',or.-*-, 80s Drop (Against the Steam | Two-Pipe Only | Vertical Hori zontal Special Capacities pob One-Pipe Systems Only Supply Boers UpFeed (Radiator! Valves and Vertical Con- . nectioos | Radiator and Riser Run outs Jb K La % 1 39 lH 87 134 2 273 2H 449 3 822, 3H 1,228 4 1,738 5 3,214 6 5,276 8 10,983 10 120,043 12 J32.168 16 160,506 30 46 56 79 111 157 100 122 173 245 346 15S[ 190 269 380 538 315 386 546 771 1,091 518 635 898 1,270 1,797 948 1,163 1,645 2,326 3,289 419 1,7371 2,457 3,474 4,913 Oil 2,457 3,475 4,914 6,950 ,7121 4,546 6,429 9,092 12,858 ,0941 7,462 10,553 14,924 21,105 ,682 15,533 21,967 31,066 43,934 ,1441(28,345 40,085 56,689 80,171 ,145| 45,4921 64,336 90,985 128,672 ,671 84,849! 121,012 169,698 ,242,024 26 58 95 195 395 700 150 1,700 '3,150 25 45 98 152 288 464 799 1,144 1,520 20 20 55 55 81 81 165 165 260 475 745 1,110 12,180 Mains and On- Up- [Radiator AU Goriaootal Mains and Down-Feed Risers dripped Feed Con Run Risers nections I __________________________________________ _ outs Note.--Ail drops shown are in pounds per 100 ft of equivalent run--based on pipe properly reamed. aDo not use Column B for drops of 1/24 or 1/32 lb; substitute Column C or Column B as required. .bDo not use Column J for drop of 1/32 lb except on sizes 3 in. and over; below 3 in. substitute Column B cOn radiator runouts over 8 ft long increase one pipe size over that shown in Table 8. r . . . ( Ahesicas Society or Heating and Ventilating Engineers ) Not to be Reprinted Wlth- L*opynijni | Pipino <md Air Condilionuio Coritmctri NafionafAttocwfion J out Special Permission 1. For the steam main and dripped runouts to risers where the steam and condensate Bow in the same direction, use fie-lb drop (Column D). 2. Where the riser runouts are not dripped and the steam and" condensation flow in opposite directions, and also in the radiator runouts where the same condition occurs, use Column L. 3. For up-feed steam risers carrying condensation back from the radiators, use Column J. - 4. For damn-feed systems the main risers of which do not carry any radiator con densation, use Column H. . 5. For the radiator valve size and the stub connection, use Column K. 6. For the dry return main, use Column TJ. 7. For the wet return main use Column T. On systems exceeding an equivalent length of 200 ft, it is suggested that the total drop be not over Y/i lb. The return piping sizes should correspond with the drop used on the steam side of the system. Thus, where H4-lb drop is being used, the steam main and dripped runouts would be sized from 295 ' T a b le 9. R e tu r n Pip e C a p a c itie s ' * . Capacity Expressed in Square Feet o f Equivalent D irect Radiation . (Reference to this table w ill be b y column le tte r U through B E ) I' : CAPACITY OF RETURN MAINS AND RISERS This table is based on pipe size data developed through the research investigations of the A' merican Society op H sating ANP'VHNTiLATiNc_ ENcmBgRS. '~ HEATING VENTILATING AIR CONDITIONING CUIDE 1940 296 C opyright { *><= W ith o u t Special Perm ission CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS Column C; radiator runouts and undripped riser runouts from Column L; uo-feed risers from Column J; the main riser on a down-feed system from Column C (it will be noted that if Column if is used the drop would exceed the limit of Hi lb); the dry return from Column R; and the wet return from Column Q. With a J^-lb drop the sizing would be the same as for Hi lb except that the steam main and dripped runouts would be sized from Column B, the main riser on a down-feed system from Column B, the dry return from Column 0, and the wet return from Column N. Table 10. Pipe Sizes for One-Pipe Up-feed System Shown in Fig. 2 Pabt or SrsTEM Branches to radiators.. Branches to radiators.. Riser____________ ____ Riser..-........................... Riser_......................... -- Branch to riser............. Supply main-------------Branch to supply main Dry return main.......... Wet return main.......... Wet return main_____ Wet return main.......... orSection Pip ___ atob b to c ctod d to e e to / /tog g to h h toj f to * k to m mton n to p Radiation Supplied (SqFt) Tbeoebtical Pipe size (Inches) Practical Pips bob (Inches) 100 2 2 50 m 1M 200 2 2 300 2H 2 H 400 2H 2H 500 3 3 600 3 3 600 3H 3 H 600 3 3 600 2H 3 600 l H '2 600 1 2 600 1 2 600 1 2 ni ^ nu Fig. 2. Riser, Supply Main and Return Main of One-Pipe System /. s' Example S. Size the one-pipe gravity steam system shown in Fig. 2 assuming that this is all there is to the system or that the riser and run shown involve the longest run on the system. Solution. The total length of run actually shown is 215 ft. If the equivalent length of run is taken at double this, it will amount to 430 ft, and with a total drop of H lb the drop per 100 ft will be slightly less than He lb. It would be well in this case to use Hi lb, and this would result in the theoretical sizes indicated in Table 10. These theo retical sizes, however, should be modified by not using a wet return less than 2 in. while the main supply, g-h, if from the uptake of a boiler, should be made the full size of the main, or 3 in. Also the portion of the main k-m should be made 2 in. if the wet return is made 2 in. Notes on Gravity One-Pipe Air-Vent Systems 1. Pitch of mains should not be less than H in. in 10 ft. 2. Pitch of horizontal runouts to risers and radiators should not be less than H lo in 10 ft. Where this pitch cannot be obtained runouts over 8 ft in length should be one size larger than called for in the table. . 3. In general, it is not desirable to have a main less than 2 in. The diameter of the far end of the supply main should not be less than half its diameter at its largest part. 4. Supply mains, branches to risers, or risers, should be dripped where necessary. 297 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 5. Where supply mains are decreased in size they should be dripped, or be provided with eccentric couplings, flush on bottom. TWO-PIPE GRAVITY AIR-VENT SYSTEMS The method employed in determining pipe sizes for two-pipe gravity air-vent systems is similar to that described for one-pipe systems except that the steam mains never carry radiator condensation. The drop allowable per 100 ft of equivalent run is obtained by taking the equiva lent length to the farthest radiator as double the actual distance, and then dividing the allowable or desired total drop by the number of hundreds of feet in the equivalent length.- Thus in a system measuring 400 ft from the boiler to the farthest radiator, the approximate equivalent length of run would be 800 ft. With a total drop of 34 lb the drop per 100 ft would be -- or 3(6 lb; therefore, Column D would be used for all O steam mains where the condensation and steam flow in the same direc tion. If a total drop of 34 lb is desired, the drop per 100 ft would be )<q lb and Column B would be used. If the total drop were to be 1 lb, the drop per 100 ft would be 34 lb and Column E would be used. For mains and riser runouts that are not dripped, and for radiator runouts where in all three cases the condensation and steam flow in opposite directions, Column I should be used, while for the steam risers Column H should be used unless the drop per 100 ft is Hi lb or 3<q lb, when Columns B or C should be substituted so as not to exceed the drop permitted. On an overhead down-feed system the main steam riser should be sized by reference to Column II, but the down-feed steam risers sup plying the radiators should be sized by the appropriate Columns B through G, since the condensation flows downward with the steam through them. The riser runouts, if pitched down toward the riser as they should be, are sized the same as the steam mains, and the radiator runouts are made the same as in an up-feed system. -. In either up-feed or down-feed systems the returns are sized in the same manner and on the same pressure drop basis as the steam main; the return mains are taken from Columns O, R, U, X, or AA according to the drop used for the steam main; and the risers are sized by reading the lower part of Table 9 under the column used for the mains. The hori zontal runouts from the riser to the radiator are not usually increased on the return lines although there is nothing incorrect in this practice. The same notes apply that are given for one-pipe gravity systems. TWO-PIPE VAPOR SYSTEMS ' While many manufacturers of patented vapor heating accessories have their own schedules for pipe sizing, an inspection of these sizing tables indicates that in general as small a drop as possible is recommended. The reasons for this are: (1) to have the condensation return to the boiler by gravity, (2) to obtain a more uniform distribution of steam throughout the system, especially when it is desirable to carry a moderate or low fire, and (3) because with large variation in pressure the value of gradu ated valves on radiators is destroyed. 298 CHAPTER 16. PIPING FOR SJEAM HEATING SYSTEMS For small vapor systems where the equivalent length of run does not exceed 200 ft, it is recommended that the main and any runouts to risers that may be dripped should be sized from Column D, while riser runouts not dripped and radiator runouts should employ Column I. The up-feed steam risers should be taken from Column H. On the returns, the risers should be sized from Column U (lower portion) and the mains from Column U (upper portion). It should again be noted that the pressure drop in the steam side of the system is kept the same as on the return side except where the flow in the riser is concerned. On a down-feed system the main vertical riser should be sized from Column H, but the down-feed risers can be taken from Column D al though it so happens that the values in Columns D and H correspond. This will not hold true in larger systems. For vapor systems over 200 ft of equivalent length, the drop should not exceed 34 lb to 34 lb, if possible. Thus, for a 400 ft equivalent run the drop per 100 ft should be not over 34 lb divided by 4, or 3^ lb. In this case the steam mains would be sized from Column B; the radiator and undripped riser runouts from Column /; the risers from Column B, because Column H gives a drop in excess of % lb. On a down-feed system, Column B would have to be used for both the main riser and the smaller risers feeding the radiators in order not to increase the drop over lb. The return risers would be sized from the lower portion of Column 0 and the dry return main from the upper portion of the same column, while any wet returns would be sized from Column N. The same pressure drop is applied on both the steam and the return sides of the system. Notes on Vapor Systems 1. Pitch of mains should not be less than 34 in. in 10 ft. 2. Pitch of horizontal runouts to risers and radiators should not be less than in. in 10 ft. Where this pitch cannot be obtained runouts over 8 ft in length should be one size larger than called for in the table. 3. In general it is not desirable to have a supply main smaller than 2 in. 4. When necessary, supply main, supply risers, or branches to supply risers should be dripped separately into a wet return, or may be connected into the dry return through . a thermostatic drip trap. VACUUM, ORIFICE, SUB-ATMOSPHERIC SYSTEMS Vacuum, atmospheric, sub-atmospheric and orifice systems are usually employed in large installations and have total drops varying from )4 to 34 lb. Systems where the maximum equivalent length does not exceed 200 ft preferably employ the smaller pressure drop while systems over 200 ft equivalent length of run more frequently go to the higher drop, owing to the relatively greater saving in pipe sizes. For example, a sys tem with 1200 ft longest equivalent length of run would employ a drop per 100 ft of 34 lb divided by 12, or Hi lb. In this case the steam main wou|d be sized from Column C, and the risers also from Column C (Column H could be used as far as critical velocity is concerned but the drop would exceed the limit of Hi lb). Riser runouts, if dripped, would use Column C but if undripped would use Column T, radiator runouts, Column I; return risers, lower part of Column S; return runouts to radiators, one pipe size larger than the radiator trap connections. . 299 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Notes on Vacuum Systems 1. It is not generally considered good practice to exceed ^i-lb drop per 100 ft of equivalent run nor to exceed 1 lb total pressure drop in any system. 2. Pitch of mains should not be less than }4 in. in 10 ft. 3. Pitch of horizontal runouts to risers and radiators should not be less than 3^2 in. in 10 ft. Where this pitch cannot be obtained runouts over 8 ft in length should be one size larger than called for in the table. 4. In general it is not considered desirable to have a supply main smaller than 2 in. 5. When necessary, the supply main, supply riser, or branch to a supply riser should be dripped separately through a trap into the vacuum return. A connection should not be made between the steam and return sides of a vacuum system without interposing a trap to prevent the steam from entering the return line. 6. Lifts should be avoided if possible, but when they cannot be eliminated they should be made in the manner described in Chapter 15. 7. No lifts can be used in orifice and atmospheric systems. In sub-atmospheric systems the lift must be at the vacuum pump. BOILER CONNECTIONS Steam Cast-iron, sectional heating boilers usually have several outlets in the top. Two or more outlets are sometimes used to reduce the velocity of the steam in the vertical uptakes from the boiler and thus to prevent water being carried over into the steam main. i> Return Cast-iron boilers are generally provided with return tappings on both sides, while steel boilers are generally equipped with only one return tapping. Where two tappings are provided, both should be used to effect proper circulation through the boiler. The return connection should include either a Hartford loop or a check valve to prevent the accidental loss of boiler water to the returns with consequent danger of boiler ' damage. The Hartford loop connection is to be-preferred over the check valve because the latter is apt to stick or not close tightly and, further more, because the check valve offers additional resistance to the con densate coming back to the boiler, which in gravity systems would raise the water line in the far end of the wet return several inches4. Hartford Return Connection In order to prevent the boiler from losing its water under any circum stances, the use of the Hartford connection, or the Underwriters Loop, is recommended. This connection for a one- or two-boiler installation is shown in Fig. 3. The essential features of construction of a Hartford Loop connection are: (1) a direct connection (made without valves) between the steam side of the boiler and the return side of the boiler, and (2) a close nipple connection about 2 in. below the normal boiler water line from the return main to the boiler steam and return pressure balance connection. Equalizing pipe connections between the steam and return are given in Fig. 3, based on grate areas, but in no case shall this pipe size be less than the main return piping from the system. 4See method of calculating height above water line for gravity one-pipe systems in Chapter 15. 300 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS Sizing Boiler Connections Little information is available on the sizing of boiler runouts and steam headers. Although some engineers prefer an enlarged steam header to serve as additional steam storage space, there ordinarily is no sudden demand for steam in a steam heating system except during the heating-up period, at which time a large steam header is a disadvantage rather than an advantage. The boiler header may be sized by first computing the maximum load that must be carried by any portion of the header under any conceivable method of operation, and then applying the same schedule of pipe sizing to the header as is used on the steam mains for the building. The horizontal runouts from the boiler, or boilers, may be sized by calculating the heaviest load that will be placed on the boiler at any time, and sizing the runout on the same basis as the building mains. The . difference in size between the vertical uptakes from the. boiler and the horizontal main or runout is compensated for by the use of reducing ells. Return connections to boilers in gravity systems are made the same size as the return main itself. Where the return is split and connected to two tappings on the same boiler, both connections are made the full size of the return line. Where two or more boilers are in use, the return to each may be sized to carry the full amount of return for the maximum load which that boiler will be required to carry. Where two boilers are used, one of them being a spare, the full size of the return main would be carried to each boiler, but if three boilers are installed, with one spare, the return line to each boiler would require only half of the capacity of the entire system, or, if the boiler capacity were more than one-half the entire system load, the return would be sized on the basis of the maximum boiler capa city. As the return piping around the boiler is usually small and short, it should not be sized to the minimum. 301 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 With returns pumped from a vacuum or receiver return pump, the size of the line may be calculated from the water rate on the pump discharge when it is operating, and the line sized for a very small pressure drop, the size being obtained from the Chart for Pressure Drop for Various Rates of Flow of Water, Fig. 3, Chapter 44. The relative boiler loads should be considered, as in the case of gravity return connections. Boiler header and piping sizes should be based on the total load. HIGH PRESSURE STEAM When high pressure steam is being supplied and lower steam pressures are required for use in heating, domestic hot water, utility services, etc., one or more pressure reducing valves, or pressure regulators; as they are sometimes called, are required. These are used in two classes of service, one where the steam must be shut off tight to prevent the low pressure building up at time of no load, and the other where the low pressure lines will condense enough steam to offset normal leaking through the valve. In the latter case, double seated valves may be used in a manner that reduces the work required of the diaphragm in closing the valve and consequently the size of the dia phragm. These valves also control the low pressures more closely under conditions of varying high pressures. . Valves that shut off all steam are called dead end type. They are single seated, and some of them have pilot operation that provides close control of the reduced pressure. If a thermostatically controlled valve is installed after, and near, a reducing valve in such a manner as to cut off the passage of steam, the dead end type should be used. It is common practice when the initial steam pressure is 100 lb or higher to install two-stage reduction. This makes a quieter condition of steam flow, as it is apparent that with one reduction, as for example, from 150 to 2 lb, there is a.smaller opening with greater velocity across the reducing valve, and consequently, more noise. -A. two-stage reduction also introduces a source of safety, since if one reducing valve were to build up its discharge pressure, this excess pressure would not be as great as the case might be in a one-stage reduction. If an installation requires single seated valves, and the pilot type cannot be used, it is necessary to use two-stage reduction, as single seated valves require sufficient diaphragm area to overcome the unbalanced pressure underneath the single valve. In many cases the large diameter of diaphragm required would make it impractical in construction. With a two-stage reduction the diaphragm diameter required would be reduced. If a one-stage reduction is desired, it is necessary to use a pilot controlled pressure reducing valve, where low pressures are to be maintained closely. In making two-stage reduction, allowance should be made, by in creasing the pipe size, for expansion of steam on the low pressure side of the valve. This also allows steam flow to be at a more nearly uniform velocity. Separating the valves by a distance up to 20 ft is recommended to reduce excessive hunting action of the first valve. When the reduced pressure is approximately 15 lb or lower, the weight and lever diaphragm valve gives the best results with minimum main tenance. Above 15 lb, spring loaded diaphragm valves should be used, 302 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS because of the extra weights required on weight and lever type. Equalizing line connections should be made not too close to the valve, and into the bottom of the reduced pressure steam main, to allow maximum conden sation to exist in this equalizing line, or the connection is made into the top of the main and a water accumulator used to reduce the variation of the head of water on the diaphragm. Care should be exercised in selecting the size of a reducing valve. The safest method is to consult the manufacturer. It is essential that sizes of piping to and from the reducing valve be such that they will pass the desired amount of steam with the maximum velocity desired. A' common error is to make the size of the reducing valve the same size as that of the service, or outlet pipe size. Generally, this will make the reducing valve oversized, and bring about wire-drawing of valve and seat, due to small lift of the valve seat. On installations where the steam requirements are relatively large and variable in mild weather or reduced demand periods, wire-drawing may occur. To overcome this condition, two reducing valves are installed in parallel, with the sizes selected on a 70 and 30 per cent proportion of maximum flow. For example, if 50,000 lb of steam per hour are required, the size of one valve is on the basis of 0.7 + 50,000 lb, or 35,000 lb, and the other on the basis of 0.3 + 50,000 lb, or 15,000 lb. During the mild or reduced demand periods, steam will flow through the smaller valve only. During the remainder of the season, the larger valve is set to control at whatever low pressure is desired, and the smaller one at a somewhat lower pressure. Thus, when steam flow is not at its maximum, the smaller valve is shut, and automatically opens when the maximum steam demand occurs, since this maximum demand of steam creates a slight pressure drop in the service line. . The installation of reducing valves in pipe lines requires detailed planning. They should be installed to give ease of access for inspection' and repair, and wherever possible with diaphragm downward, except in cases of pilot operated valves. There should be a by-pass around each reducing valve of size equal to one half the size of reducing valve. The glove valve in by-pass line should be of a better type of construction, and must shut off absolutely tight. A steam pressure gage, graduated up to the initial pressure should be installed on the low pressure side. Safety valves located on the low pressure side should be set 5 lb higher than the final pressure but may be 10 lb higher than the reduced pressure if this reduced pressure is that of the first stage reduction of a double reduction. Strainers should always be installed on the inlet to the reducing valve but are not required before a second-stage reduction. If a two-stage reduction is made, it is well to install a pressure gage immediately before the reducing valve of the second-stage reduction also. In sizes 3 in. and above, it is advisable to tap the bodies of the reducing valve on inlet side for purposes of draining condensate accumulation through steam traps. Control Valves Gate valves are recommended in all cases where service demands that the valve be either entirely open or entirely closed, but they should never 303 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 be used for throttling. Angle globe valves and' straight globe valves should be used for throttling, as done on by-passes around pressure reducing valves or on by-passes around traps. Connection to Heating Units Riser, radiator and convector connections must not only be properly pitched at the time they are installed but must be arranged so that the pitch will be maintained under the strains of expansion and contraction. These connections may be made by swing joints which permit the ex pansion or contraction to occur under heating and cooling without bending of pipes. To take care of expansion in long risers, either expansion joints "Runout below floor PLAN ^iscr fi|'|i|"|ii|!i"'! inia Radiator 1 1 Globe _Runou.t vvalv e above \ jfloor \ r . tfot Air valve --| ! /Floor! r "'Runout below floor ELEVATION Fig. 4. One-Pipe Radiator Connections Fig. 5. Unit Heater Connected to One-Pipe Air-Vent System of commercial construction or pipe swing joints are used. Anchoring of pipes between expansion joints is desirable. Fig. 4 illustrates two satisfactory methods of making runouts for one-pipe systems for either the up-feed or the down-feed type. Where the vertical distance is limited and the runouts must run above the floor the radiator may be set on pedestals or of the high leg type. A method of connecting a unit heater to a one-pipe steam heating system is illus trated in Fig. 5. Figs. 6, 7 and 8 show typical two-pipe radiator or convector connections. While the top is the preferred location for the control valve, it may be located at the bottom. Short radiators may be top supply and bottom return on same end. With convectors the control valve is sometimes omitted and a damper in outlet grille used for heat control. The typical method of connecting pipe coils is shown in Fig. 9 and is suitable for atmospheric, vapor, vacuum, sub-atmospheric, and orifice systems. 304 CHAPTER 16. PIPINC FOR STEAM HEATING SYSTEMS Figs. 10, 11, 12 and 13 show typical pipe connections-for indirect radiators and tempering or heating stacks. Where a building is served by a vacuum system or a sub-atmospheric system the stacks should be piped in the usual manner and traps of large capacity, preferably of the combination float and thermostatic type, should be used. In the orifice and dosed, two-pipe systems, traps should be used on the returns so that a pressure above that of the atmosphere may be secured on the heaters. Eccentric Fig. 6. Typical Connections for Two-Pipe System HP' fccantrie 'talitat Fig. 7. Top and Bottom Opposite End Radiator Connections Fig. 8. Connections to Radiator Hung on Wall Each stack should have a,separate steam and return connection. Wide stacks are more evenly heated with two steam connections, one at each end, the stacks being divided and a return connection provided for each steam connection. For stacks of large capacity it. is sometimes desirable to run a separate steam main direct from the boiler to the stacks. PIPE SIZING FOR INDIRECT HEATING UNITS Pipe connections and mains for indirect 'heating units are sized in a manner similar to radiators, but the equivalent direct radiation must be ascertained for each row of heating unit stacks and then must be. divided into the number of stacks constituting that row and into the number of connections to each stack. FDR = Q X 60 X (t| - fe) = Q X (t| - fe) 55.2 X 240 220.8 ' 305 U) HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Fig. 10. Typical Piping Connections to Concealed Heating Units with Wet Returns Indirect radiator Fig. 11. Piping Connections to Indirect Radiators CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS where jtDR = equivalent direct radiation, square feet. Q = volume of air, cubic feet per minute. Ij = the temperature of the air entering the row of heating units under con sideration, degrees Fahrenheit. <1 = the temperature of the air leaving the row of heating units under considera tion, degrees Fahrenheit. 60 = the number of minutes in one hour. 55 2 = the number of cubic feet of air heated 1 F by 1 Btu. 240 = the number of Btu in 1 sq ft of EDR. Example 4- Assume that the heating units shown in Fig. 14 are handling 50,000 cfm of air and that the rise in the first row is from 0 to 40 F, in the second row from 40 to 65 F and in the third row from 65 to 80 F. What is the load in EDR on each supply and return connection? Solution. For row 1, 50,000 X (40 - 0) R= 220.8 = 9058 sq ft. For row 2, ,, R 50,000 X (65 - 40) _ __ ----------- 2208----------- 5661 ** lt- For row 3, R = 50,000 X (80 - 65) 220.8 3397 sq ft. row of heating units consists of four stacks and each stack has two connections so that the load on each stack and each connection of the stack is as follows: Row i 2 3 Total Load (EDR) 9058 5661 3397 Stack Loads (EDR) 2265 1415 849 Cootsenow Load*> (EDR) 2265 or 1132 1415 or 708 849 or 425 aOne quarter of total row load. .. bOse half of stack load If two steam connections are made: otherwise, same as stack load. The pipe sizes would then be based on the length of the run and the pressure drop desired, as in the case of radiators. It generally is considered desirable to place the in direct heating units on a separate system and not on supply or return lines connected to the general heating system. DRIPS A steam main in any type of steam heating system may be dropped to a lower level without dripping if the pitch is downward with the direction of steam flow. Any steam main in any heating system can be elevated if dripped. Fig. 15 shows a connection where the steam main is raised and the drain is to a wet return. If the elevation of the low point is above a dry return it may be drained through a trap to the dry return in two-pipe vapor, vacuum and sub-atmospheric systems. Horizontal steam pipes may also be run over obstructions without a change in level if a small pipe is carried below the obstruction to care for the condensation (Fig. 16). 307 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 16. PIPING FOR STEAM HEATING SYSTEMS Branches from steam mains in one-pipe gravity steam systems should use the preferred, connection shown in Fig. 18, but where radiator condensa tion does not flow back into the main the acceptable method shown in the same figure may be used. This acceptable method has the advantage of giving a perfect swing joint when connected to the vertical riser or radia tor connection, whereas the preferred connection does not give this swing Fig. 12. Supply and Return Con nections for Heating Units of Central Fan Systems Fig. 13. Typical Connections to Central Fan System Heating Units Exceeding 12 Sections Horizontal return pipes may be carried past doorways and other ob structions by using the scheme illustrated in Fig. 17. It will be noted that the large pipe, in this case, runs below the. obstruction and the smaller one over it. Fig. 15. Dripping Main Where it Rises to Higher Level Fig. 16. Looping Main Around Beam Fig. 17. Looping Dry Return Main Around Opening Acceptable method Preferred method Fig. 18. Methods of Taking Branch from Main To find length C-multipfy A bjr constant for angle B Fig. 19. Constantsfor Determining Length Offset Pipe Fig. 20. Dirt Pocket Connection -Supply <r Cooling leg at />wst S` long Fig. 21. Dripping End of Main into Wet Return Fig. 22. Dripping End of Main into Dry Return Fig! 23. Dripping Heel of Riser into Dry Return without distorting the angle of the pipe. Runouts from the steam main are usually made about 5 ft long to provide flexibility for movement in the main. Offsets in steam and return piping should preferably be made with 90-deg ells but occasionally fittings of other angles are used, and in such cases the length of the diagonal offset will be found as shown in Fig. 19. Dirt pockets, desirable on all systems employing thermostatic traps, should be so located as to protect the traps from scale and muck which 309 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 will interfere with their operation. Dirt pockets are usually made 8 in. to 12 in. deep and serve as receivers for foreign matter which otherwise would be carried into the trap. They are constructed as shown in Fig. 20. On vapor systems where the end of the steam main is dripped down into the wet return, the air venting at the end of the main is accomplished by an air vent passing through a thermostatic trap info the dry return line as shown in Fig. 21. On vacuum systems the ends of the steam mains are dripped and vented into the return through drip traps opening into the return line. The same method may be used in atmospheric systems. A float type trap is preferable to a thermostatic trap for dripping steam mains and large risers. If thermostatic traps are used a cooling leg (Fig. 22) should always be provided. The cooling leg is for cooling the condensation sufficiently before it reaches the trap so the trap will not be held .shut by too high a temperature. On down-feed systems of atmos pheric, vapor, and vacuum types, the bottom of the steam risers are dripped in the manner shown in Fig. 23. On large systems it is desirable to install a gate valve in the cooling leg ahead of the trap. 310 Chapter 17 hot water heating systems and piping One- and Two-Pipe Systems, Selecting Pipe Sizes, Forced Circulation, Gravity Circulation, Expansion Tanks, Instal lation Details SYSTEMS for heating with hot water radiators may be divided into two general classes, the first known as gravity systems in which circulation is caused by the difference in density of the water in the flow and return lines, and the second known as forced circulation systems in which circulation is caused by a pump. Flow water temperatures vary from 150 to 220 F and the higher temperatures are generally used with the forced system. For the sizing and selecting of boilers, radiators and piping, refer to Chapters 13, 14 and 18 respectively. SYSTEMS OF PIPING There are two general systems of piping used for either gravity or forced hot water systems: (a) Two-pipe system. (b) One-pipe system. With either of these piping systems the distributing mains may be located in the cellar with up-feed to the radiators and risers or the supply main may be located in the attic with the return main located in the cellar. With the latter system of piping, the one-pipe system would be only one pipe for the risers. For basement radiators located on the floor the mains may be run at the ceiling, as one of the advantages of a forced hot water heating system is that the returns need not be below the radiators as required with a steam system. With some one-pipe systems there is one main in the cellar but separate flow and return risers and connections to the radiators. In the two-pipe system there is separate supply and return pipes throughout so that the same water flows only through one radiator, resulting in the same water temperature in all radiators. With the onepipe system part of the water flows through more than one radiator, so that the water temperature toward the end of the main is not as hot as near the boiler. However, with the one-pipe system, by maintaining a rapid circulation and small difference in temperature between the water leaving and returning to the boiler or other heat generator, the tendency to have variable temperatures in the radiators is much reduced. The two-pipe system for larger buildings should, if possible, be arranged for reversed return. The direct and reversed return systems are shown 311 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 in Figs. 1 and 2. With the reversed return system, the water has to travel approximately the same distance from and back to the boiler for any one radiator as for any other radiator, and therefore, the friction and temperature losses to all radiators should be nearly the same. In some cases the reversed return system involves no more piping than the direct return system. In the case of large buildings, it might be advisable to zone the piping. Mechanical Circulators Circulating pumps are usually of the centrifugal type. The capacity of the pump is figured from the Mbh (symbol representing 1000 Btu per hour) required for heating and the drop in temperature selected. For example, for 100 Mbh and 20 F drop a pump having a capacity of 5000 lb water per hour or 10 gpm. The resistance head is based on the system as designed. In large systems the economical, size of pump may be deter mined by comparing the cost of power for operation, with the annual charges on the capital cost of the piping system, as larger pipe sizes mean less pump power. Velocities through piping in excess of 4 fps are likely to cause disturbing noises in buildings other than factories. In large Fig. X. A Direct Return System Fig. 2. A Reversed Return System systems the pumps are run continuously while in small ones they are run either continuously or intermittently depending on the type of auto matic temperature control selected. Small circulating pumps are usually driven by direct-connected electric motors. Under'certain conditions a valved by-pass should be provided and the piping so designed that in case of breakdown of the pump or failure of electric current there will be sufficient-gravity circulation to keep the building reasonably warm.. In large buildings or groups of buildings, it is often advisable to have two pumps, each of about 70 per cent of the total capacity to take care of. breakdown service. During mild weather, variations in water tempera ture may be utilized to balance the required heat loss. In the larger systems steam turbines are sometimes used to drive the pumps, the exhaust steam being used for heating the water, and in such buildings as hospitals this is usually the most economical method. . As the average pump used for water circulation is not over 60 per cent efficient, the cost of power on a large job should be figured and com parisons made between the .savings made in capital cost of piping and the annual cost of power. FORCED CIRCULATION PIPE SIZES The. pressure heads available in forced circulation systems are much greater than those in gravity circulation systems, consequently, higher 312 CHAPTER 17. HOT WATER HEATING SYSTEMS AND PIPING velocities may be used in designing the system, with the result that smaller pipes may be selected and the first cost of the installation reduced. . As the pipe sizes of a heating system are reduced, the necessary increase' in the velocity of the water increases the friction iosses and thus the cost of operation and the initial cost of the circulating equipment. The increased velocity of a forced circulation system offers a number of advantages, such as a much shorter heating-up period and a more flexible control of hot water circulation. This improved performance merits the small increase in operating cost necessary to circulate the water mechani cally- The velocities required should be determined by calculation for the particular system under consideration. Since forced circulation velocities are higher than those in gravity systems, and since the friction heads in a heating system vary almost as the squares of the velocities, a given error in the calculation or assump tion of a velocity is less important in a forced circulation system than in a gravity circulation system, and, consequently, it is easier to design a satisfactory forced circulation system than a satisfactory gravity circu lation system. : In forced hot water systems, it is customary to use a temperature drop of 20 or 30 F between the water entering and leaving the boiler or other heater. The head against which the system is to operate must then be decided. This varies from 2 to 5 ft for small systems and may rise to 100 ft on large jobs with a group of buildings. For iron pipe, the sizes can be figured using Fig. 3 and Tables 1 and 3. For copper tubing Tables 2 and 3 are.to be used. In systems designed with reversed returns, it will generally be found that very little adjustment is necessary to secure even distribution to all radiators. However, orifices may be used to control the flow and the capacities are given in Table 5. In large buildings provision should be made for quickly draining radiators in case of breakage, and it is often advisable to install a lock shield valve on one end of each radiator and a hand controlled valve on the other. In case of breakage the two valves can be closed and the radiator removed without effecting the rest of the system. The lock shield valve can also be used for balancing the water circulation. ' The following examples will illustrate the procedure to be followed in designing forced circulation systems. ' ' . Example 1. From the plan of Fig. 4 note that the longest, circuit consists of 151 ft of iron pipe; 1 boiler; 1 radiator; 1 radiator valve; 1 stop cock; 10 ells and 3 tees; and the shortest circuit consists of 127 ft of pipe; 4 tees; 1 boiler; 1 radiator; 1 radiator valve; 1 stop cock; and 6 ells. Design the piping for this system. . .; Solution. The friction in the various fittings can be expressed in terms of the friction in a 90-deg elbow from the values given in Table 3. . The longest circuit consists of 151 ft of pipe and 44 elbow equivalents. The short circuit consists of 127 ft of pipe and 39 elbow equivalents. The friction head in one elbow is approximately equal to the friction produced by the same sized pipe 25 diameters in length. Assume that the average pipe size for this system is 1 in. The equivalent length of the longest circuit will be 151 ft plus 100 ft or 251 ft of pipe. The equivalent length of the short circuit will be 217 ft.; , Having determined the equivalent length of the circuits, the next step is to assume the rate at which the water is to be circulated in the system. The water may flow through the system so that it will cool any reasonable number of degrees. For the most economi cal average system a 20 F drop seems to be a satisfactory rate. This entails a slower water flow from the pumping equipment with a reasonable relationship between pipe 313 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 1. Equivalent Length of Pipe vs. Pressure Head at Various Friction Losses Steel Pipe Miunch Friction Loss Per Foot of Pipe Head . Loss, 720 480 360 300 240 ISO 160 144 120 96 90 80 70 60 Fr . Equivalent Length of Pipe in Feet 2 2K 3 3H 4 5 &>$ 6 6H 7 7Vi 8 8H 9 10 10H 11 HH 12 33 50 66 80 100 133 150 167 200 250 270 300 340 400 42 50 62 84 75 100 100 125 167 120 150 200 188 208 250 312 333 375 428 225 .250 300 375 400 450 510 500 600 59 67 87 117 100 133 140 175 233 160 200 266 263 300 291 350 437 463 525 593 333 400 500 533 600 685 700 800 75 112 149 180 225 300 338 374 450 562 593 675 758 900 83 125 167 200 250 333 375 416 500 625 666 750 860 1000 92 137 183 220 275 366 413 457 550 687 713 825 923 1100 100 150 200 240 300 400 450 500 600 750 800 900 1030 1200 108 162 217 260 325 433 488 540 650 812 843 975 1088 1300 116 175 233 280 350 465 525 580 700 875 933 1050 1200 1400 124 187 249 300 375 500 563 623 750 937 973 1125 1252 1500 133 200 266 320 400 533 600 666 800 1000 1070 1200 1370 1600 142 150 212 283 225 300 340 425 566 360 450 600 638 675 706 850 1062 1103 1275 1417 1700 750 900 1125 1200 1350 1540 1800 159 237 317 380 475 633 713 789 950 1187 1233 1425 1577 1900 167 250 333 400 500 666 750 833 1000 1250 1333 1500 1715 2000 175 262 349 420 525 700 788 872 1050 1312 1363 1575 1737 2100 183 275 366 440 550 733 825 916 1100 1375 1466 1650 1885 2200 192 287 383 460 575 766 863 955 1150 1437 1533 1726 1897 2300 200 300 400 480 600 800 900 1000 1200 1500 1600 1800 2030 2400 Nominal Pipe Size, Capacity of Pipes Mbh With a 20 Fa Deop A Carrying Capacity, B = Velocity, inches Per second Friction Head of Pipe Milinches per foot 720 480 360 300 240 180 160 144 120 96 .90 80 70 60 A MB 20 16 14 13 11 10 9 9 8 7 7 6 6 27 22 19 17 16 18 12 11 10 9 9 8 8 5 7 A %B 43 35 30 27 24 21 19 18 17 15 14 13 12 S3 26 28 21 18 16 16 14 18 11 // 10 9 11 9 A 1B 85 70 60 54 48 41 39 36 33 30 28 27 25 89 82 27 25 22 19 .18 17 16 13 IS 12 11 23 10 A mb A 1H B A 2B 180 145 125 115 98 85 80 75 68 60 58 55 51 - 43 89 88 80 27 28 21 20 19 16 15 16 U 285 230 195 180 160 135 125 120 110 96 92 88 82 64 44 88 34 80 26 34 28 21 19 18 17 15 540 435 370 340 300 255 240 230 205 180 175 165 150 64 62 46 40 86 80 29 . 27 34 22 21 20 19 47 12 75 H 140 17 `A 2H B A ZB ' A' 3^4 B 890 720 610 550 480 420 390 370 330 300 280 270 250 230 74 60 50 46 41 85 88 31 28 34 34 22 21 19 1650 1340 1130 1000 900 760 720 670 600 540 520 480 450 88 70 60 64 48 41 88 36 88 29 28 26 34 410 22 2500 2000 1700 1500 1350 1150 1080 1000 900 800 760 720 670 620 99 78 60 64 46 4S 40 38 82 81 29 27. 25 A 4B A 5B 3500 no 7000 IS2 2800 87 5600 106 2400 74 4700 90 2200 66 4300 80 1900 1600 68 60 3700 3200 70 60 1520 47 3000 66 1440 46 2750 63 1300 40 2500 48 1150 85 2200 42 1100 34 2100 41 1050 82 2000 88 960 80 1800 85 880 27 1700 SB A 6B 6112.000 9200 7800 7000 6200 5200 4800 4600 4100 3600 3500 3300 3000 2800 . 166 124 104 94 82 . 69 64 . 66 . 48 46 44 .41 87 *For other temperature drops the pipe capacities may be changed correspondingly.' For example, with' a temperature drop of 30 F, the capacities shown in this table are to be multiplied.hy 1.5. . 314 CHAPTER 17. HOT WATER HEATINC SYSTEMS AND PIPING Table 2. Equivalent Length of Tube vs. Pressure Head at Various Friction Losses Type L Copper Tube Milinch Friction Loss per Foot of Tube ,- HEAD LOSS. 720 600 480 360 300 240 ISO 150 120 90 75 60 FT Equivalent Length of Tube in Feet (LongbST ClRCUIT) ------------- 2H 3 " 3H 50 75 40 50 50 63 60 75 70 88 80 100 90 113 67 83 100 117 133 150 80 100 133 160 100 125 167 200 120 150 200 240 140 175 233 280 160 200 267 320 180 225 300 360 200 267 320 400 250 333 400 500 300 400 480 600 350 467 560 700 400 533 640 800 450 600 720 900 --------- - 100 125 167 200 250 333 400 5H 6 110 138 100 120 150 183 200 220 240 275 300 367 400 440 480 130 163 217 260 325 433 520 140 175 233 280 350 467 560 7H 125 150 188 250 300 375 500 600 ~~ 8 8M 9 133 160 200 170 213 150 180 225 267 283 300 320 340 360 400 425 450 533 567 600 640 680 720 500 667 800 1000 550 733 880 1100 600 800 960 1200 650 867 1040 1300 700 933 1120 1400 750 1000 1200 1500 800 1067 1280 1600. 850 1133 1360 1700 900 1200 1440 1800 9H 10 10K 159 190 238 167 200 250 175 210 263 317 333 350 380 400 420 475 500 525 633 667 700 760 950 1267 1520 1900 800 1000 1333 1600 2000 840 1050 1400 1680 2100 11 11 X 12 183 220 275 192 230 288 200 240 300 367 383 400 440 460 480 550 575 600 733 767 800 880 1100 1467 1760 2200 920 1150 1533 1840 2300 960 1200 1600 1920 2400 Nominal Tube Capacity of Tubes Mbh With a 20 F* Drop / = Carrying Capacity, B = Velocity, inches per second Friction Head of Pipe Milinches per Foot In. A MB A HB A HB A XB A 1B A IX B A 1M B A 2B A tX B A 3B A 3M B A 4B 720 600 480 360 10 9 8 6.8 27 24 . 21 18 20 18 16 13.5 S3 80 26 21 36 30 26 22.1 57 34 50 34 51 46 40 34 43 88 55 27 104 94 82 70 48 46 39 34 185 169 149 125 65 61 46 59 300 270 235 200 62 67 61 43 625 560 495 420 76 68 69 61 1130 1010 890 750 90 80 69 68 1840 1650 1450 1210 98 90 80 66 2750 2480 2170 1840 110 too 89 76 3900 3505 3100 2600 120 108 96 88 300 6.2 16 12 19 20 21 31 34 63 30 112 86 180 59 375 47 680 49 1100 69 1650 66 2350 75 240 5.4 14 10.8 17 17.8 19 28 21 56 26 100 50 160 36 335 43 600 47 980 62 1450 57 2090 63 180 4.6 18 9 16 15 17 23.2 19 47 22 84 26 134 SO 280 86 500 43 820 47 1210 61 1760 55 150 4 11 8 IS 13.1 16 20.5 17 42 19 75 22 120 25 250 82 450 87 740 43 1100 46 1580 49 120 3.6 10 7 12 11.8 IS 18.1 14 37 17 66 29 105 22 200 27 395 88 650 86 980 40 1390 44 90 75 3 2.8 8.5 8 6 5.4 10 9 9.9 11 9 10 15.3 12 13.9 11.6 32 - 28 14.6 13 56. 50 17 15 90 81 19 17 188 170 . 22 20 335 305 26 28 550 490 80 27 820 740 86 SO 1180 87 1080 34 60 2.4 7 4.7 8 7.9 9 12.1 10 25 12 44 13 71 16 150 18 . 270 21 420 28 650. 26 950 29 ' "For other temperature drops the pipe capacities may be changed correspondingly. For example, with a temperature drop of 30 F. the capacities shown in this table are to be multiplied by 1.5. 315 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 size and Bow. Assume 20 F drop for this system. One gallon of water per minute with a density of 7.99 at 215 F will deliver approximately 9600 Btu per hour with a 20 F drop. CHAPTER 17. HOT WATER HEATING SYSTEMS AND PIPING IT nwinF that the rate of flow is 10.2 gpm, the next step is to determine from the Knowing ava;iable pumps, which one will produce a satisfactory velocity in the character's that 4 pumps are available for this load which will produce 10.2 gpm at system. ss 10 and 18 ft. At these heads the pumps would produce a velocity enouS to make available a friction head per foot of pipe of 96 240, 480 and 860 hf,, Ter foot respectively. If 95 milinches per foot were used, the gravity head at Jl' F amraee temperature in the mains would be 26 per cent of the total head and ` 2U5 ih he considered in sizing the system. At 240 milinches per foot the gravity effect is inner centand as this is lower than the delivery variation from the pipe used, it can be 10 ^ tS At 480 and 860 milinches the gravity effect is still a smaller percentage of FRICTION HEAD IN MILINCHES PER FOOT OF PIPE Fig. 3. Friction Heads in Black Iron Pipes for a 20 F Temperature Difference, of the Water in the Flow and Return Lines For other temperature drops the pipe capacities may be changed'correspondingly. For example, with a temperature drop of 30 F, the capacities shown in this table are to be multiplied by 1.5, .. The total radiation load is 98 Mbh, therefore'the pump must deliver 10.2.gpm or 4900 lb of water per hour." . .. .. 316 Fig. 4. A Forced Circulation Reversed Return System3 Note that the numbers on the radiators indicate thousands of Btu per hour (Mbh) and not square feet, the total, but at these losses in the average system the cost of pumping will more than offset the advantage gained in pipe sizes. Therefore, pipe size this system at 240 milinches per foot .which is equivalent to a total loss of 60,000 milinches for the 250 ft equivalent length of pipe. . :^ The pipe sizes may be selected from Fig. 3 or from Table 1 which'has been derived from Fig. 3. # Size the supply main of the longest circuit first. Section AB carries 98 Mbh. From Fig. 3 it will be noted that at 240 milinches per foot,, a lK-in. pipe carries 98 Mbh. Therefore, use d^-in. pipe in Section AB. Section BO carries 40 Mbh. A 1-in. pipe carries 48 Mbh at 240 milinches per foot. Use a 1-in. pipe. Section OP carries 20 Mbh . 317 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 3. Iron and Copper Elbow Equivalents Fitting Iron Pipe Elbow, 90-deg......................... ............................................... Elbow, 45-deg................................:........................................ Elbow, 90-deg long turn.............. ........................................ Open return band_.................-.............................................. Open gate valve...........................................................:......... Open globe valve. -.................... ................................ ...... Angle radiator valve..... ....................................................... Radiator............................................................ ..................... Boiler or heater....................................................................... Tee, per cent flowing through branch: 100-- .............................. .................................................. 5a ................................................................................. 25--............................ :................... :.............................. 1.0 0.7 0.5 1.0 0.5 12.0 2.0 3.0 3.0 1.8 4.0 16.0 Copper Tubing 1.0 0.7 0.5 1.0 0.7 17.0 3.0 4.0 4.0 ' 1.2 4.0 20.0 and this will require 5i-in. pipe. Section PQ carries 10 Mbh and requires Yi in. pipe. To size the return start from the boiler and proceed backwards. Section IR carries 40 Mbh and from Fig. 3 a 1-in. pipe is required. Section RS carries 30 Mbh which is only slightly over the capacity of a in. pipe, so use M in. Section ST carries 20 Mbh and requires a 54-in. pipe. The radiator branches are determined in the same manner. It is evident from the chart that it is impossible to maintain a constant friction loss per foot and therefore as the delivery varies there will be a change in the desired friction loss per foot of pipe. . Table 4. Piping Check Chart Load. Mbh Pipe Length Ft Elbows Pipe Size In. Unit Head Milinches pee Ft ' Friction Milinches Total Loss Milinches Supply Main AB 98 BC 58 CD 38 DE 23 EF 11 FG 4 37 1 lH 240 9600 9.600 2 4 IK 90 1080 10,680 16 11 155 2790 13.470 9 0 x 220 1980 15.450 12 0 X 240 2880 18,330 16 1 X 50 850 19.180 Return Main HI 98 IJ 58 JK 54 KL 47 LM 35 MN 20 5 5 IK 240 4320 4,320 11 1 tK 90 1260 5,580 16 11 300 5400 10.880 11 01 230 2530 13,410 9 01 140 1260 14.670 15 1 K 170 2890 17.560 Radiator Circuits CN 20 Supply . Return DM 15 Supply Return EL 12 Supply Return FK 7 Supply Return GJ 4 Supply Return 3 13 42 3 4. 19 17 14 20 15 20 3 19 4 . 17 8 5 9 17 K 170 3910 X 170 1190 5,100 X 420 9250 X 96 2880 12,130 X 270 9180 X 270 9450 18,630 100 2200 H 100 2100 4,300 X 50 650 X 50 . 1300 1.950 318 hot water heating systems and piping rt is desirable to check the various circuits so that if the variation from the calculated stance is too great, it may be compensated by adding additional resistance at the f rooer point. This may be accomplished by sizing the short circuits by the procedure J/Smslv outlined. Prepare a chart such as Table 4 to be used in calculating the resSisetacnticoen oAfBeaccahrrcieirsc9u8it.Mbh with a unit head of 240 milinches per foot. In section AB there are 37 ft of pipe and 1) in. elbow. At 240 milinches per foot this is equivalent to 9600 milinches total loss in this section. Section BC carries 58 Mbh with a length of 2 ft and 4 elbows. The unit loss in this section is 90 milinches per foot. Loss in this section is then 1080 milinches. Section CD carries 38 Mbh and has 16 ft of pipe and 1 elbow. The unit loss in 1-in. pipe is 155 milinches. The loss in this section is 2790 milinches. The balance of the supply main and the return main are handled in a similar manner. The radiator circuits are then checked. The 20 Mbh radiator on this circuit has 3 ft of supply pipe and 13 elbow equivalents while the return is composed of 4 ft and 2 elbows. The unit loss in % in. pipe at this delivery is 170 milinches per foot. The total loss in the supply is 3910 milinches. The loss in the return is 1190. Total loss in the radiator circuit is 5100 milinches. Check each radiator circuit in a similar manner. The total calculated loss for the longest circuit was determined as 60,000 milinches. The maximum loss in the short circuit is 18,630 plus 13,410 plus 15,450 or a total of A Forced Circulation Direct Return System Fig, 5. 47,490 milinches. This difference is caused by the variation in length of the two circuits and may be corrected by using a flow control in the return main to supply the additional resistance or by introducing resistance into each separate circuit to compensate for the difference. A10 per cent variation will cause no complication as the flow from thevarious pipes will not exactly follow the curves of Fig. 3 any closer than this value. - Example S. Design a two-pipe direct return forced circulation system with copper tubing and fittings for the piping layout as detailed in Fig. 5, based on a 20 F tempera turTehderoppiptihnrgoucgirhcuthitefrroamdiatthioenb. oiler to the highest radiator on the farthest riser and back to the boiler is 250 ft of pipe. There are about 16 elbow equivalents having an equivalent pipe length of about 50 ft, so that the total equivalent pipe length is 300 ft. Assume that a circulator is available which will provide a pressure head of 6 ft. Solution. Refer to Table 2, which indicates the total equivalent lengths for pressure heads from 2 to 12 ft. With a circulator having a 6 ft pressure head and a system with a total equivalent length of 300 ft, the piping system will be designed on a basis of 240 milCinhcehc.king the piping diagram it will be noted that sections AB and KA, both supply 117.6 Mbh. Referring to the 240 milinch column of Table 2,1)4 in. is shown to be the necessary pipe size. Sections BC and JK carry 88.8 Mbh and require 1)4 in. tubing. Sections CD and IJ supply 67.2 Mbh and require 1)4.in. tubing. Sections DE and HI supply 43.2 Mbh, which requires 1 in. tubing;. Sections EF and GH with a load of 14.4 Mbh require % in. tubing. - . . :/ The risers are pipe sized in a similar manner. To secure proper distribution of hot HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 water in the direct return system among the several risers, it is necessary to introduce resistances to balance the circuit. The first riser is 80 ft nearer the boiler than the fifth riser. In order that the two may be balanced, that is, operated under equal pressure heads, resistance must be added to CHAPTER 17. HOT WATER HEATING SYSTEMS AND PIPING GRAVITY CIRCULATION PIPE SIZES In gravity hot water heating systems the difference in temperature (density) between the flow and return produces the circulation of the water. The temperature difference is usually made from 25 to 35 F. Having determined the temperature difference and the temperature of flow, Fig. 6 can be used to obtain the pressure head, and from this point the calculations are the same as for forced hot water. Heat emission rates from 150 to 170 Btu per square foot are commonly used so that flow temperatures range from 180 to 200 F or higher. Assuming a flow temperature of 200 F and 35 F drop and the mains 4 ft above the boiler, a circulating pressure head of 600 milinches results. Assuming first floor radiators 3 ft above the mains and second floor radiators 12 ft above mains, third floor 21 ft and fourth floor 30 ft, the circulating pressure heads are 450, 1800, 3150 and 4500 milinches respectively. the first.riser equal to the friction head in the 80 ft of supply main B to F plus the 80 ft of return main G to K for a total of 160 ft of pipe. . Having designed the piping system on a 240 milinch basis, the total friction head in tbe supply and return mains between the first and fifth risers is therefore 160 X 240 = 38,400 milinches, or 3.2 ft which must be supplied by additional resistance in the first riser: This resistance can be supplied by an adjusting valve or by an orifice of size selected from Table 5. 320 Fig. 7. A One-Pipe Gravity Circulation System The following examples will illustrate the method to be followed in designing a gravity hot water system: Example S. Design a one-pipe gravity circulation system for the layout shown in Fig. 7. Assume that the main circuit consists of 150 ft of pipe, 7 elbows, and one boiler. Solution. Replace the boiler by 3 elbow equivalents and assume that the size of the main will be about 2 in. According to Table 6, Column 2, a 2-in. elbow is equivalent to 4 ft of pipe, and the total equivalent length of the main will be about 150^pius 40, or 190 ft. Assuming that the center of the boiler will be about 4 ft lower than the horizontal portion of the main and that the temperature drop in the system is to be 35 F, Table 6 may be used to determine the size of the mains. Note from Column 8, for a 200 ft length, that a 2-in. main will supply 48 Mbh and a 2^-in. main, 75.4 Mbh. Since the system to be designed is to supply 66 Mbh, a 2-in. pipe is too small and a 2J^-in. pipe too large. The solution is to use some 2 in. and some 2H in. pipe. Since the 2*^ in. is nearer the correct size than the 2 in., select 2-in. pipe for the first 50 or 60 ft from the boiler and 2% in. for the remaining pipe back to the boiler. Tables 7 and 8 may be used to design the radiator risers and connections. According to Table 7, for 12 Mbh the flow riser should be % in. and the return riser 1 in., and the riser branches should be 1 in. and 1 }4 in., respectively. Note that according to Table 8, both radiator tappings should be 1 in. To simplify the construction, select 1-in. flow risers with 1-in. riser branches and 1-in. radiator tappings. Also select lM-in. return risers with lj^-in. riser branches, and lK-in. radiator tappings. Similarly, for IS Mbh, select lK-in. flow and return risers and riser branches, and 13^-in. radiator tappings. To develop a rule for determining radiator sizes, assume a system similar to that of Fig. 7, in which the total temperature drop is to be 35 F 321 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Table 5. Friction Heads (in Milinches) of Central Circular Diaphragm Orifices in Unions Dujotbb or Velocity or Water in Pipe in Feet per Minute -- Orifices (Inches) 10 .5 20 j 30 | 40 | 50 | 60 j 90 | 120 | 180 ' 0.25 0.30 0.35 0.40 0.45 0.50 0.55 1300 650 330 170 2900 1450 740 380 185 5000 2500 1300 660 330 155 75 %-tn. Pipe- 11,300 5700 2900 1500 740 350 170 20,800 10,400 5200 2600 1300 620 300 32,000 16,000 8000 4000 2000 970 480 45,000 23,000 12,000 6800 2900 1400 700 57,000 26,000 13,000 6500 3200 1600 47,000 24^000 53,000 12,000 27^000 5700 13,OCXl 2800 6400 0.35 0.40 0.45 0.50 0.55 0.60 0.65 900 2000 3500 460 1000 1800 270 570 1000 160 330 580 190 330 200 120 7800 4000 2300 1400 750 440 260 1-in. Pipe 14,000 7200 4100 2300 1300 800 460 22,000 12,000 6400 3700 2200 1300 720 32,000 17,000 9300 5400 3000 1800 1100 37,000 21,000 12,000 7000 4200 2400 -- 65,000 37*000 22'000 50,nno 13,000 28,000 7400 17J3QO 4300 io;o6o 0.45 0.50 0.55 0.60 0.65 0.70 0.75 1000 660 430 280 190 2250 1450 950 630 420 285 190 4000 2600 1700 1100 750 510 330 1 14-in, Pipe 8900 5800 3800 2500 1700 1150 750 16,000 10,400 6800 4400 3000 2000 1300 25,000 16,400 10,500 6900 4700 3100 2100 36,000 23,000 15,000 10,000 6700 4500 3000 53,000 34j000 22,000 15,000 10,000 6700 60,000 40'000 27'000 60,oon 18,000 40 f non 12,000 26,000 0.55 0.60 0.65 0.70 0.75 0.80 u.85 850 1900 3300 600 1300 2300 400 850 1500 260 600 1100 180 400 760 300 540 200 380 1 \j-in. Pipe 7400 5400 3600 2600 1800 1200 860 13,000 8600 7200 4400 3000 2200 1600 21,000 30,000 -- - 16,800 21,000 50,000 10,400 14,000 30j000 7000 10,000 21,000 5000 . 7000 14,000 3200 5000 10,200 2300 3000 7800 53,000 39^000 28,000 19;000 45,000 13,000 30,000 0.70 0.80 0.90 1.00 1.10 1.20 1.30 890 1850 3500 470 975 1800 255 560 1000 160 340 610 214 . 375 195 2-in. Pipe 7400 3900 2200 1320 850 460 275 14,000 7400 4200 2520 1600 950 525 22,300 11,700 6500 4000 2500 1360 980 33,000 17,000 9500 5800 3700 1910 1375 , 37,000 20,500 12,500 7900 4200 3100 38,000 23,000 14,000 8100 4400 Note.--The losses of head for the orifices io the IH-in. and 2-in. pipe were calculated from those in the smaller pipes, the calculations being based on the assumption that, for any given velocity, the loss of head is a function of the ratio of the diameter of the pipe to that of the orifice. This had been found to be ' practically true in the tests to determine the losses of head in orifices in 1-in,, and pipe, con ducted by the Texas Engineering Experiment Station, and also in the tests to determine the losses of head In orifices in 4-in., fi-in., and 12-in. pipe, conducted by the Engineering Experiment Station of the University of Illinois, (Bulletin 109, Table 6, p. 38, Davis and Jordan). CHAPTER 17. HOT WATER HEATING SYSTEMS AND PIPING and which is equipped with 7 radiators, all radiators dissipating equal Quantities of heat. The mean temperature of the water in the radiators will be reduced 5 F for each successive radiator. If the mean temperature of the water in the first radiator is 200 F, the mean temperature of the water in the seventh radiator will be 170 F, and, according to Table 4, Chapter 14, the heat dissipation of these two radiators will be to each pther as 1.62 is to 1.15, or as 140 is to 100, and therefore if the last radiator is to dissipate as much heat as the first, its size must be 40 per cent larger. Example 4- Design a two-pipe, direct return, gravity circulation system for the lay out shown in Fig. 8. Assume that the main circuit from the boiler to the farthest flow riser and from the farthest return riser back to the boiler consists of 160 ft of pipe, 6 elbows, and 1 boiler. Solution. Replacing, the boiler by 3 elbow equivalents and assuming that the largest size of the main will be about 3 in., the total equivalent length of the main will be 160 plus 45, or 205 ft. Assuming that the center of the boiler will be about 4 ft lower than the horizontal portion of the main, and that the temperature drop will be 35 F for the system, the pressure head caused by the difference in weight between the water in the flow and return risers joining the mains to the boiler will be about 0.6 in. of water. Table 6 may be used to determine the size of the main as follows: Refer to Column 8 and note that for Sections AB and IA, which supply 105.6 Mbh, a 3-in. pipe is too large and a 2)-in. pipe is too small; hence, select 2)4 in. rather than 3 in. as noted in Fig. 8 for Section AB and 3 in. for Section IA. For Sections BC and HI, which supply 76.8 Mbh, a 2)4-in. pipe is almost exactly the correct size and is selected for both sections. Tables 7 and 8 are based on the assumption that the boiler pressure head must be equal to the friction head in the mains, and that the several radiator pressure-heads must be equal to the respective radiator and riser friction heads. To design the radiator risers, use Table 7 and begin with the set nearest the boiler. The first floor risers must supply 28.8 Mbh. According to the table, 154-in. flow and return risers will supply 26.0 Mbh; if the return riser is increased to 1)4 in., the capacity will be increased to 34.0 Mbh. This is considerably larger than necessary, and 1^-in. flow and return risers are selected. However, it must be remembered that the riser branches, which are the connections from the flow and return mains to the flow and return risers, are to be one size larger than the risers. The second floor risers must supply 19.2 Mbh. According to the table, the capacity of 1 in. flow and return risers is 20.0 Mbh, and that size is selected. The third floor risers must supply 9.6 Mbh. If a )4-in. flow anda %-in. return riser 323 * HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Table 6. Capacities of Mains in Mbh, for One-Pipe and foe Two-Pipe Direct Return Gravity Circulation Systems with a Total Friction Head of 0.6 In., a Temperature Drop of 35 F, when the Mains are 4 Ft above the Center of the Boiler 1( 2 3 4 5 ( 6 | 1 1 8 j 9 1 10 | II Pins Sob (Inches) Equivalent Length of Pipe (Feets) Equivalent Total Length of Pips in Feet in Longest Cmcirr |75 | 100 125 150 US | 200 | 230 | 300 350 ~ Unit Friction Head, in Milinches m 2 2X 3 3X 4. 3.0 4.0 4.5 5.0 5.5 6.0 8.0 6.0 4.8 4.0 3.4 3.0 2.4 2.0 u 4S.0 37.5 33.0 30.0 27.0 25.0 82.2 20.2 18.7 83.0 78.0 63.0 67.0 51.0 48.0 42.0 38.0 35.0 140.0 115.0 100.0 90.0 81.5 75.4 67.2 61.0 66.0 834.0 204.0 175.5 160.0 148.0 133.0 110.0 107.5 100.0 347.0 300.0 260.0 236.0 214.O 200.0 177.0 160.0 146.0 490.0 482.0 370.0 334-0 297.0 278.0 248.0 223.0 205.0 -.pp.vAimaw t***.u ui the velocity. iu ieev equivalent iq one eioow in triction bead. This value varies with ' is used, the capacity will be 8.0 Mbh; if both risers are X in., the capacity will be 14.0 Mbh. The J^-in. pipe is selected for both risers. To design the radiator connections, use Table 8 and note that for the first floor radiator connections the capacity of a Ji'-in. flow and 1-in. return is 9.1 Mbh, and that of a 1-in. flow and a 1-in. return is 12.5 Mbh. The former is more nearly the correct site, but since it is difficult to secure a good flow through first floor radiators, the 1-in. flow and return connection is selected. For the two upper floors, the capacity of a %-in. flow and return connection is 10.5 Mbh, and that size is used. Table 7. Maximum Capacities of Risers3 in Mbh, and Velocities of Water in Pipes in Inches Per Second for One-Pipe and for Two-Pipe Direct Return Gravity Circulation Systems with "a'-Drop of 35 F through Each Radiator Pipe Sizs (Inches) Flow Return Equivalent Length of Pipe (Fexttc) In Floob*> Mbh Vel (In. per Seed) Flow Return 2nd Floob 3bd and 4th Floors Mbh - Mbh X X XX X1 1.0 1.5 9 2.3 2.3 12 3.2 2.0 6 6.4 10.1 12.8 e.e 8.0 14.0 17.1 11 1 IX 2.0 18 2.5 2.5 21 3.0 2.0 80 85.8 86.0 H ix ix IX 3.0 26 3.0 3.0 34 4.0 2.5 4S 65 3.5 48. 3.0 3.0 ____________ --^___ __ ,w> aw, tow, oiuv, tuiu tow icstwcuveiy, tor cue uni) secona. third, and fourth floor radiators, and on friction heads of 200 milinches for the first floor radiators and con nections, and 700 milinches for all other radiators and their connections. bThe riser branches, the piping which connects the risers to the mains, are to be one size larger than the risers. . oApproximate length of pipes in feet equivalent to one elbow in friction head. This value varies with the velocity. ^Velocities apply to the riser branches. 324 CHAPTER 17. HOT WATER HEATING SYSTEMS AND PIPING _ , ,, a Maximum Capacities of Radiator Connections in MSA, for One-Pipe TA and for Two-Pipe Direct Return Gravity Circulation Systems with PifsSos Return Equivalent Length of Pipe (Feet) X X X X X Xl ll l 1M iX lX 1.0 1.5 2.0 3.0 .innmrimate lennth of pipe in feet equivalent 1st Floob Mbh 2nd, 3rd, and 4th Floors Mbh 4.1 6.8 7.0 9.1 18.6 17.6 83.3 . 5.9 7.5 10.6 13.0 17.8 83.8 33.8 As explained in the design of the forced circulation system of Fig. 5, the two-pipe direct return system of Fig. 8 will not function correctly unless its four sets of risers are balanced among themselves. This neces sary balancing is accomplished by adding resistances to all risers, except the one farthest from the boiler, equal to the excess boiler pressure heads available for those risers above the boiler pressure head available for the farthest riser. For example, the first set of risers is 60 ft nearer the boiler than the last set. Since the flow and return mains are designed for a friction head of 3 milinches per foot (see Table 6, Column 8), the boiler pressure head available for the first set of risers is 360 milinches in excess of that available for the fourth set. The velocity in the riser branch is 3 in. per second (see Table 7) and, therefore, according to Table 5, an 0.65-in. orifice in a lj^-in. union should be used. This will provide a resistance of about 420 milinches. In the same manner it is found that for the second set of risers a resistance of 240 milinches is required and that an 0.70-in. orifice in a lj^-in. union will provide a resistance of 285 325 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 milinches. For the third set of risers, a resistance of 120 milinches is required and an 0.60-in. orifice in a 1-in. union will provide sufficient resistance. EXPANSION TANKS Expansion tanks may be either of the open or of the closed type. In the open type, (see Fig. 9) the water is subject to atmospheric pressure only, but in the closed tank (see Fig. 10) the system is under pressure and, therefore, a relief valve should be placed on the tank. Water expands, about 4 per cent when being heated from 40 F to 200 F, and the expansion tank should have a volume about twice the actual expansion or about 8 per cent of the total volume of water in the entire system including boiler, radiators, pipes, etc. Open expansion tanks should be at least 3 ft above the highest radiator and be protected against freezing. Closed tanks are generally placed in the cellar over the boiler. A relief valve installed on a closed tank will not.operate often provided the tank is of adequate size. It is essential that the relief valve be kept in good condition to eliminate any possible failure when operation is necessary. INSTALLATION DETAILS Attention should be paid to the following: All piping must be so pitched that all air in the system can be vented either through an open expansion tank, radiators or automatic relief valves. All piping must be arranged so that the entire system can be drained. Sections of piping individually valved shall have corresponding drain valves. In large buildings, the piping may be zoned according to exposure of building usage of building or method of control. All piping must be installed so that it'is free to expand and contract with changes of temperature without producing undue stresses in the pipes or connections. For this purpose it is generally sufficient to allow for a variation in length of 1 in. for 100 ft of pipe. The pipe system should be designed so that each circuit has its correct friction head for balanced water distribution. . This may be done by change of pipe size or change in piping detail. . The connections from the boiler to the mains should be short and direct, to reduce the friction head and allow for expansion. It is frequently possible to avoid an elbow and to reduce the length of the pipe by running the pipe in a diagonal direction, either in a horizontal or in a vertical plane. The mains and branches should pitch up and away from the heater, generally not less than 1 in. in 10 ft. The connections from mains to branches and to risers should be such that circulation through the risers will start in the right direction. Hence, in a one-pipe system the flow connection must be nearer the heater than the return connection. In a correctlydesigned two-pipe system, the pressure in the flow main is higher than that in the return main, and a slight variation in the distances of the flow and return connections from the heater is not material; but it is generally best to have the two connections about equally distant from the heater. Generally connections to risers or radiators are taken out of the top of mains either 45 or 90 deg. In some cases it may be advisable to take the flow connection off the top of the main and the return connection from the side. With forced circulation and high velocities, it is advisable to let the water enter at the top of the radiator and leave at the bottom of the opposite end. With gravity circulation the flow connection may be either at the top or at the bottom of the radiator. With short radiators both flow and return may be at same end, but top and bottom. Unless used as heating surface, all piping, both flow and, return, should be insulated. 326 Chapter 18 PIPE, FITTINGS, WELDINC Pipe Material, Types of Pipe Used, Dimensions of Pipe Com mercially Available, Expansion and Flexibility of Pipe, Pipe Threads and Bangers, Types of Fittings, Welding as Applied to Erection of Piping, Valves, Corrosion of Piping IMPORTANT considerations in the selection and installation of pipe and fittings for heating, ventilating, and air conditioning work are dealt with in this chapter. PIPE MATERIALS Use of corrosion-resistant materials for pipe, including special alloy steels and irons, wrought iron, copper and brass, has increased con siderably during the past few years. The recent development of copper, brass, and bronze fittings which can be assembled by soldering or sweating permits the use of thin-wall pipe and thereby has reduced the initial cost of such installation. The following brief discussion indicates the variety of pipe materials and the types of pipe available. Wrought-Steel Pipe. Because of its low price, the great bulk of wrought pipe used for heating and ventilating work at the present time is of wrought steel. The material used for steel pipe is a mild steel made by the add-bessemer, the open-hearth, or the electric-furnace process. Ordinary wrought-steel pipe is made either by shaping sheets of metal into cylindrical form and welding the edges together, or by forming or drawing from a solid billet. The former is known as welded pipe, the latter as seamless pipe. Many types of welded pipe are available, although the smaller sizes most frequently used in heating and ventilating work are made by the lap-weld, resistance-weld, or butt-weld process. While the lap-weld and resistance-weld processes produce a better weld than the butt type, lap-weld and resistance-weld pipe is seldom manufactured in nominal pipe sizes less than 2 in. Seamless pipe can be obtained in the small sizes at a somewhat higher cost. Seamless steel pipe is frequently used for high pressure work or where pipe is desired for close coiling, cold bending, or other forming operation. Its advantages are its somewhat greater strength which permits use of a thinner wall and, in the small sizes, its freedom from the occasional tendency of welded pipe to split at the weld when bent. Wroughl-Iron Pipe. Wrought-iron pipe is claimed to be more corro sion-resisting than ordinary steel pipe and therefore its somewhat higher 327 1 j i HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 first cost is said to be justified on the basis of longer life expectancy. Wrought-iron pipe may be identified by the spiral line marked into each length, either knurled into the metal or painted on it in red or other bright color. Otherwise, there is little difference in the appearance of wrought iron and steel pipe, although microscopic examination of polished and etched specimens will readily disclose the difference. $ Cast Ferrous Pipe. There are now available several types of cast ferrous-metal pipe made of a good grade of cast-iron with or without additions of nickel, chromium, or other alloy. This pipe is available in sizes from 1 in. to 6 in., and in standard lengths of 5 or 6 ft with external and internal diameters closely approximating those of extra strong wrought pipe. Cast ferrous pipe may be obtained coupled, beveled for welding, or with ends plain or grooved for the several types of couplings. It is easily cut and threaded as well as welded. The fact that it is readily welded enables the manufacturers to supply the pipe in any lengths practicable for handling. Alloy Metal Pipe. Steel pipe bearing a small alloy of copper or other alloying element and iron pipe bearing a small alloy of copper and moly bdenum have been claimed to possess more resistance to corrosion than plain steel pipe and they are advertised and sold under various trade names. Copper Pipe and Fittings. Owing to its inherent resistance to cor rosion, copper and brass pipe have always been used in heating, venti lating, and water supply installations, but the cost with standard dimen sions for threaded connections has been high. The recent introduction of fittings which permit erection by soldering or sweating allows the use of pipe with thinner walls than are possible with threaded connections, thereby reducing the cost of installations. The initial cost of brass and copper pipe installations generally runs higher than the corresponding job with steel pipe and screwed connections in spite of the use of thin-wall pipe, but the corrosive nature of the fluid conveyed or the inaccessibility of some of the piping may warrant use of a more expensive material than plain steel. The advantages of corrosionresisting pipe and fittings should be weighed against the correspondingly higher initial cost. COMMERCIAL PIPE DIMENSIONS The IPS dimensions of commercial pipe universally used at the present i time conform to the recommendations made by a Committee of the A.S.M.E. in 1886. Pipe up to 12 in. in diameter is made in certain definite sizes designated by nominal internal diameter which is somewhat different from the actual internal diameter, depending on the wall thick ness required. There are three weights of wrought iron and steel pipe commonly used, known as standard-weight, extra-strong, and double extra strong. Because of the necessity of maintaining the same external dia meter in all three weights for the same nominal size, the added wall thickness is obtained by decreasing the internal diameter. The term full-weight, when applied to sizes below 8 in., means that the pipe is up to the nominal weight per foot. When applied to sizes between 8 and 12 in., inclusive, it often indicates that the pipe has the heaviest of several wall 328 , CHAPTER 18. PIPE. FITTINCS, WELDING thicknesses listed. In sizes 14 in. and upward, pipe is designated by its outside diameter (O.D.) and the wall thickness is specified. While the demands for pipe for the heating and ventilating industry are reasonably well served by the standard-weight and extra-strong pipe, demands for pipe for higher pressures and temperatures in industry resulted in the use of a multiplicity of wall thicknesses for all sizes. Even in heating installations, the erection of piping by welding was deemed to Table 1. Dimensions of Welded and Seamless Steel Pipe Nominal Wall Thicknesses fob Schedule Numbers NOHINIL Pm Shi Outside Duh. 10 Schedule 20 Schedule 30 Schedule 40 Schedule 60 Schedule 60 Schedule 100 Schedule 120 Schedule 140 Schedule 160 Ml H H H % 1 IH 1H 2 VA 3 3A 4 5 6 8 10 12 14 0 D. 16 0. D. 18 0. D. 20 0. D. 24 O. D. 30 0. D. 0.405 0.540 0.068* 0 088* 0.095* 0.119* 0.675 0 091* 0.126* 0 109* 0.147* 0.113* 0.154* 1.315 0.133* 0.179* 0.140* 0 191* 0.145* 0.200* 0.154* 0.218* 0.203* 0.276* 0.216* 0.300* 0.226* 0.318* 0.237* 0.337* 0.437 0.258* 0.375* 0.500 0.280* 0.432* 0.562 0.250 0.277* 0.322* 0.406 0.500* 0.593 0.718 0.812 10.75 0.250 0.307* 0.365* 0.500* 0.593 0.718 0.843 1.000 12.75 0.250 0.330* 0.406f 0.562f 0.687 0.843 1.000 1.125 14.0 0.250 0.312 0.375 0.437 0.593 0.750 0.937 1.062 1.250 16.0 0.250 0.312 0.375 0.500 0.656 0 843 1.031 1.218 1.437 18.0 0.250 0.312 0.437 0.562 0.718 0.937 1.156 1.343 1.562 20.0 0 250 0.375 0.500 0.593 0 812 1.031 1.250 1.500 1.750 24.0 0 250 0.375 0.562 0.687 0.937 1.218 1.500 1.750 2.062 30.0 0.312 0.500 0.625 0.187 0.218 0.250 0.250 0.281 0.343 0.375 0.437 0.531 0.625 0.718 0.906 1.125 1.312 1.406 1.562 1.750 1.937 2.312 All dimensions are given in inches. The decimal thicknesses listed for the respective pipe sizes represent their nominal or average wall dimensions. For tolerances on wall thicknesses, see appropriate material specification. Thicknesses marked with asterisk in Schedules 30 and 40 are identical with thicknesses for standard* weight pipe in former lists; those in Schedules 60 and 80 are identical with thicknesses for extra-strong pipe in former lists. . The Schedule Numbers indicate approximate values of the expression 1000 x P/S. tOwing to a necessary departure from the old standard-teeighl and extra-strong thicknesses in these two sizes, the new thicknesses are not as yet stocked by all manufacturers and jobbers, thence, where agreeable to the purchaser and suitable for the service conditions, the old standard^veight 0.375 in. wall pipe corre sponding to a 1000 P/S value of 37.7 is still available and can be substituted for the 0.406 in. wall, and the old extra-strong 0.500 in. wall pipe corresponding to a 1000 P/S value of 55 can be substituted for the 0.562 in. wall. warrant the use of pipe lighter than standard weight. For these reasons, a Sectional Committee on Standardization of Wrought Iron and Wrought Steel Pipe and Tubing functioning under the procedure of the American Standards Association was appointed to standardize the dimensions and materials of pipe. The proposed pipe standard recommended by that sectional committee has set up several schedules of pipe including standard-weight and extra strong thicknesses which are now included in Schedules 40 and 80, re- 329 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 spectively. The schedules approved by the Sectional Committee are given in Tables 1 and 3 and the corresponding weights in Tables 2 and 4. Standard-weight pipe is generally furnished with threaded ends in random lengths of 16 to 22 ft, although when ordered with plain ends, 5 per cent may be in lengths of 12 to 16 ft. Five per cent of the total number of lengths ordered may be jointers which are two pieces coupled together. Extra-strong pipe is generally furnished with plain ends in Table 2. Nominal Weights of Welded and Seamless Steel Pipe Nominal PlPB Size Inches SCHED. 10 Plain Ends SCHED. 20 Plain Ends Schedule 30 Plain Ends Threads and Coup lings Schedule 40 Plain Ends Threads and Coup lings SCHED. 60 Plain Ends Scbed. 80 Plain Ends SCHED. 100 Plain Ends SCHED. 120 Plain Ends Schnd. 140 Plain Ends SCBZD iw Plain Ends X 0.25* 0.25* 0.32* "----- - X 0.43* 0.43* 0.54* "... ^*-- % X 0.57* 0.57* 0.86* 0.86* o 74* L09* *..... % 1.14* 1.14* 1.48* 1 1.68* 1.69* 2.18* m 2.28* 2.29* 3.00* m 2.72* 2.74* 3.64* 2 3.66* 3.68* 5.03* 2X 5.80* 5.82* 7.67* 3 3X 7.S8* 7.62* 9.11* 9.21* 10.3* 12.5* 14.3 4 10.8* 10.9* 15.0* io ft 5 14.7* 14.9* 20.8* 97 1 6 19.0* 8 ___. . 22.4 24.7* 25.0* 28.6* 10 ______ 28.1 34.3* 35.0* 40.5* 12 33.4 43.8* 45.0* 53.6 14 O. D. 36.8 45.7 54.6 ....___ 63.3 16 O. D. 42.1 52.3 62.6 82.8 8 O. D. 47.4 59.0 82.0 105.0 10 O. D. 52.8 78.6 105.0 123.0 14 O. D. 63.5 94.7 141.0 171.0 50 0. D. 99.0 158.0 197.0 19.2* 28.6* 3A 4 28.8* 35.7 43.4* 50.9 60.7 67.8 74.7 41.2* 54.8* 64.4 77.0 89.2 105.0 116.0 55.0 73.2 88.6 ...____ 85.0 107.0 .... ..... 108.0 137-.0 108.0 126.0 140.0 161.0 131.0 147.0 171.0 190.0 165.0 193.0 224.0 241.0 133.0 171 0 208,0 ?*o ft 975 0 167.0 209.0 9.51 ft ?7 ft 34? 0 374 0 231.0 297.6 361.0 416.0 484.0 536.0 Wights are given in pounds per linear foot and are for pipe with plain ends except for sizes which are commercially available with threads and couplings for which both weights are listed. The weights marked with asterisk in Schedules 30 and 40 are identical with weights for standard-weight pipe in former lists; those in Schedules 60 and 80 are identical with weights for extra-strong pipe in former lists. The Schedule Numbers indicate approximate values of the expression 1000 x P/S. ' random lengths of 12 to 22 ft, although 5 per cent may be in lengths of 6 to 12 ft. In addition to IPS copper pipe, several varieties of copper tubing are in use with either flared or compression couplings or soldered joints. Dimen sions of copper water tubing intended for plumbing, underground water service, fuel-oil lines, gas lines, etc., have been standardized by the U. S. Government and the American Society for Testing Materials. There are three standard wall-thickness schedules of copper water tubing classified in accordance with their principal uses as follows: 330 CHAPTER 18. PIPE, FITTINGS, WELDING Class K--Designed for underground services and general plumbing service. Class L--Designed for general plumbing purposes. Class M--Designed for use with soldered fittings only. In general, Type K is used where corrosion conditions are severe, and Types L and M where such conditions may be considered normal as, for instance, in heating work. Types K and L are available in both hard and Table 3. Dimensions of Welded Wrought-Iron Pipe Nominal Pipe Size Y% X X X % 1 IX 2 2X 3 3X 4 5 6 8 10 12 14 0. D. 16 O. D. 18 0. D. 20 0. D. Outside Diameter 0.405 0.540 0.675 0.840 1.050 1.315 1.660 1.900 2.375 2.875 3.5 4.0 4.5 5.563 6.625 8.625 10.75 12.75 14.0 16.0 18.0 20.0 Nominal Wai.i. Thicknesses fob Schedule Numbers 10 -- -- -- 0.250 0.250 0.250 -- Schedule 20 -- -- -- 0.312 0.312 0.312 0.375 Schedule 30 -- -- -- 0.283* 0.313* 0.336* 0.375 0.375 0.437 0.500 Schedule 40 0.070* 0.090* 0.093* 0.111* 0.115* 0.136* 0.143* 0.148* 0.158* 0.208* 0.221* 0.231* 0.242* 0.263* 0.286* 0.329* 0.372* 0.414t 0.437 0.500 0.562 0.562 Schedule 60 -- ____ -- _.._.... -- 0.510*. 0.574f 0.625 0.687 0.750 -- Schedule 80 0.098* 0.122* 0.129* 0.151* 0.157* 0.183* 0.195* 0.204* 0.223* 0.282* 0.306* 0.325* 0.344* 0.383* 0.441* 0.510* 0.606 0.702 0.750 ____ All dimensions are given in inches. The decimal thicknesses listed for the respective pipe sizes represent their nominal or average wall dimensions. For tolerances on wall thicknesses, see appropriate material specification. hicknesses marked with an asterisk in Schedules 30 and 40 are identical with thicknesses for standardweight pipe in former lists; those in Schedules 60 and 80 are identical with thicknesses for extra-strong. pipe in former lists. The Schedule Numbers indicate approximate values of the expression 1000 r P/S. ` fOwing to a necessary departure from the old standard-weight and extra-strong thicknesses in these two sizes, the new thicknesses are not as yet stocked by all manufacturers and jobbers- Hence, where agreeable to the purchaser and suitable for the service conditions, the old standard-weight 0.382 in. wall pipe corre sponding to a 1000 P/S value of 38-7 is still available and can be substituted for the 0.414 in. wall and the old extra-strong 0.510 in. wall pipe corresponding to a 1000 P/S value of 56.3 can be substituted for the 0.574 in. wall. soft tempers; Type M is available only in hard temper. Where flexibility is essential as in hidden replacement work or where as few joints as possible are desired as in fuel-oil lines, the soft temper is commonly used. New or exposed work generally employs copper pipe of a hard temper. All three classes are extensively used with soldered fittings. Standard dimensions, weights, and diameter and wall thicknesstolerances for these classes of copper tubing are given in Table 5. Copper pipe is also available with dimensions of steel pipe. Refrigeration lines used in connection with air conditioning equipment 331 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 V also employ copper tubing extensively. For refrigeration use where tubing absolutely free from scale and dirt is required, bright annealed copper tubing that has been deoxidized is used. This tubing is available in a variety of sizes and wall thicknesses. EXPANSION AND FLEXIBILITY The increase in temperature of a pipe from room temperature to an operating steam or water temperature 100 F or more above room tem perature results in an increase in length of the pipe for which provision must be made. The amount of linear expansion (or contraction in the Table 4. Nominal Weights of Welded Wrought-Iron Pipe Nominal Pipe Size (Inches) SCHED. SCHKD. 10 20 Plain Plain Ends Ends M ____ H H % 1 m ix 2 2X 3 3X 4 5 __ ; ___ ____ . ____ ___ _ __ 6 8 10 12 14 0. D. 36.0 16 O. D. 41.3 18 O. D. 46.5 20 O. D. ____ __ ____ ____ ____ _ _ .. 44.8 51.4 57.9 77.0 Schedule SO Plain Ends ______ Threads and Couplings ______ ______ ______ ______ --,, ._ . ,,' 24.7* 34.3* 43.8* 53.6 61.4 80.5 103.0 _.._.._.._.._ ______ . _ _____ ____ 25.0* 35.0* 4_5_._0_* ..... -- Schedule 40 Plain Ends Threads and Couplings 0.25* 0.43* 0.57* 0.86* 1.14* 1.68* 2.28* 2.72* 3.66* 5.80* 7.58* 9.11* 10.8* 14.7* 19.0* 28.6* 40.5* 53.6 62.2 81.2 103.0 115.0 0.25* 0.43* 0.57* 0.86* 1.14* 1.69* 2.29* 2.74* 3.68* 5.82* 7.62* 9.21* 10.9* 14.9* 19.2* 28.8* 41.2* "55.0 Schedule Schedule 60 80 Plain Plain Ends Eidi* 54.8* 73.2 87.6 111 0 136.0 0.32* 0 54* 0.74* 1.09* 1.48* 2.18* 3.00* 3.64* 5.03* 7.67* 10.3* 12.5* 15.0* 20.8* 28.6* 43.4* 54.4 88.6 104.0 -- Wrights are given In pounds per linearfoot and are for pipe with plain ends except for sizes which are commercially available with threads and couplings for which both weights are listed. Weights marked with an asterisk in Schedules 30 and 40 are identical with weights for standard-weight gipe in former lists; those in Schedules 60 and 80 are identical with weights for extra-strong pipe in former The Schedule Numbers indicate approximate values of the expression 1000 x P/S. case of refrigeration lines') per unit length of material per degree change in temperature is termed the coefficient of linear expansion of that material, or commonly, the coefficient of expansion. This coefficient varies with the material. The linear expansion of cast-iron, steel, wrought iron, and copper pipe, the materials most frequently used in heating and ventilating work, can be determined from Table 6. The elongation values in Table 6 were computed from the following formula: ' 332 CHAPTER 18. PIPE, FITTINCS, WELDING where = length at temperature t degrees Fahrenheit, feet. L0 = length at 32 F, feet. i = final temperature, degrees Fahrenheit. a and b are constants as given on the next page. Metal -- Coppci------------- a 0.005441 0.006212 0.006503 0.009278 h 0.001747 0.001623 0.001622 0.001244 The three methods by which the elongation due to thermal expansion may be taken care of are: 1. Expansion joints. 2. Swive) joints. or o3f.fsIenthseinretnhteflleinxei.bility of the pipe itself utilized through pipe bends right-angle turns' Table 5. Standard Dimensions, Weights, and Diameter and Wall Thickness Tolerances for Copper Water Tubes* (All Tolerances Plus and Minus) Pesmissiblb WALL THICKNESS, IN- Weight peh Ft Actual Outside NOUItiAL Diam* Sue. In. Mean Outside In. Annealed Hard Drawn Class K Class L Class M Per Per Nominal missible Varia Nominal missible Varia Nominal missible Varia tion tion tion Class K Class L Class M %Xa 1 IIXK2 2X3 3X4 5 6 0.500 0.0025 0.001 0.625 0.0025 0.001 0.875 0.003 0..001 1.125 0.0035 0.0015 1.375 0.004 0.0015 1.625 0.0045 0.002 2.125 0.005 0.002 2.625 0.005 0.002 3.125 0.005 0.002 3.625 0.005 0.002 4.125 0.005 0.002 5.125 0.005 0.002 6.125 0.005 0.002 0.049 0.004 0 049 0.004 0.065 0.0045 0.065 0.0045 0.065 0.0045 0.072 0.005 0.083 0.005 0.095 0.005 0.109 0.005 0.120 0.005 0.134 0.006 0.160 0.006 0.192 0.006 0.035 0.0035 0.040 0.0035 0.045 0.004 0.050 0.004 0.055 0.0045 0.060 0.0045 0.070 0.005 0.080 0.005 0.090 0.005 0.100 0.005 0.110 0.005 0.125 0.006 0.140 0.006 0.025 0.0025 0.269 0.198 0.028 0.0025 0.344 0.285 0.032 0.003 0.641 0.455 0.035 0.0035 0.839 0.655 0.042 0.0035 1.04 0.884 0.019 0.004 1.36' 1.14 0.058 0.0045 2.06 1.75 0.065 0.0045 2.92 2.48 0.072 0.0045 4.00 3.33 0.083 0.005 5.12 4.29 0.095 0.005 6.51 5.38 0.109 0.005 9.67 7.61 0.122 0.005 13.87 10.20 0.144 0.203 0.328 0.464 0.681 0.94 1.46 2.03 2.68 3.58 4.66 6.65 8.91 From Standard Specifications for Copper Water Tube of the American Society far Testing Materials, AJS.T.M. Designation B88-33. Expansion joints of the slip-sleeve, diaphragm, or corrugated types made of copper, rubber, or other gasket material are all used for taking up expansion, but generally only for low pressures or where the inherent flexibility of the pipe cannot readily be used as in underground steam or hot water distribution lines. 333 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940' .Swivel joints are used extensively in low-pressure steam and hot water heating systems and in hot water supply lines. The swivel joints absorb the expansive movement of the pipe by the turning of threaded joints. In many cases the straight pipe in the offset of a swivel joint is sufficiently flexible to take up the expansion without developing enough thrust to produce swiveling in the threaded joint. This is preferable since con tinued turning in the threaded joint may in time result in a leak, par ticularly when the pressure is high. The amount of elongation which a swivel joint can take up is controlled by the length of the swing piece employed and by the lateral displacement which is permissible in the long pipe runs. . Probably the most economical method of providing for expansion of piping in a long run is to take advantage of the directional changes which must necessarily occur in the piping and proportion the offsets so that sufficient flexibility is secured. Ninety-degree bends with long, straight tangents in either a horizontal or a vertical plane are an excellent means for securing adequate flexibility with larger sizes of pipe. When flexi- Offset U bend Fig. 1. Measurement of L on Various Pipe Bends bility cannot be obtained in this manner, it is necessary to make use of some type of expansion bend. The exact calculation of the size of ex pansion bends required to take up a given amount of thermal expansion is relatively complicated1. The following approximate method, however, has been found to give reasonably good results and is deemed to be sufficiently accurate for most heating work. : Fig. 1 shows several types of expansion bends commonly used for taking up thermal expansion. The amount of pipe, L, required in each of these bends may be computed from the following formula: . L = 6.16 where : . Z = length of pipe, feet. D -- outside diameter of the pipe used, inches. A = the amount of expansion to be taken up, inches. (2) : ; This formula, based on the use of mild-steel pipe with wall thicknesses not heavier than extra-strong, assumes a maximum- safe value of fiber stress of 16,000 lb per square inch. When square type bends are used, the width of the bend should not exceed about two times the height. It is Piping Handbook, by Walker and Crocker, and A Manual for the Design of Piping for Flexibility by the Use ot Graphs, by E. A. Wert, S. Smith, and E. T. Cope, published by The Detroit Edison Company. CHAPTER 18. PIPE, FITTINGS, WELDINC further assumed that the corners are made with screwed or flanged elbows IU with arcs of circles having raJdii five to six times the pipe diameter. Use nf welding elbows with radii of l'A times the pipe diameter will decrease the end thrusts somewhat but will raise the fiber stress correspondingly.. All risers must be anchored and safeguarded so that the difference in length when hot from the length when cold shall not disarrange the normal and orderly provisions for drainage of the branches. Proper anchoring of piping is especially necessary with light-weight radiators, to allow for freedom of expansion in ordef that no pipe strain Table 6. Thermal Expansion of Pipe in Inches per 100 Ft* (For superheated steam and other fluids refer to temperature column) Saturated Steam Elongation in Inches feh 100 FT FROM --20 F up Saturated Steam ' Elongation in Inches per 100 IT FROM --20 F UP Pressure Tem Vacuum Inebes of Hg. Pounds per Square Inch Gage perature Degrees Fahren heit CastIronPipe Steel Pipe Wrought Iron Pipe Copper Pipe Pressure Pounds per Square Inch Gage Tem perature Degrees Fahren heit CastIron . Pipe Steel Pipe Wrought Iron Pipe Copper Pipe 70 3Q 209 ?7 99 26^48 74 04 20 27 14.63 6.45 -20 0 20 40 60 80 100 120 140 160 180 200 2.5 220 10.3 240 20.7 260 34.5 280 52.3 300 74.9 320 103.3 340 138.3 360 180.9 380 232.4 400 293.7 420 366.1 440 451.3 460 550.3 480 0 0 0 0 664.3 0.127 0.145 0.152 0.204 795.3 0.255 0.293 0.306 0.442 945.3 0.390 0.430 0.465 0.655 1115.3 0.518 0.593 0.620 0.888 1308.3 0.649 0.725 0.780 1.100 1525.3 0.787 0.898 0.939 1.338 1768.3 0.926 1.055 1.110 1.570 2041.3 1.051 1.209 1.265 1.794 2346.3 1.200 1.368 1.427 2.008 2705 1.345 1.528 1.597 2.255 3080 1.495 1.691 1.778 2.500 1.634 1.852 1.936 2.720 1.780 2.020 2.110 2.960 1.931 2.183 2.279 3.189 2.085 2.350 2.465 3.422 2.233 2.519 2.630 3.665 2.395 2.690 2.800 3.900 2.543 2.862 2.988 4.145 2.700 3.029 3.175 4.380 2.859 3.211 3.350 4.628 3.008 3.375 3.521 4.870 3.182 3.566 3.720 5.118 3.345 3.740 3.900 5.358 3.511 3.929 4.096 5.612 3.683 4.100 4.280 5.855 .500 520 540 560 580 600 620 640 660 680 700 720 740 760 780 800 820 840 860 880 .900 920 940 960 980 1000 3.847 4.296 4.477 6.110 4.020 4.487 4.677 6.352 4.190 4.670 4.866 6.614 4.365 4.860 5.057 6.850 4.541 5.051 5.268 7.123 4.725 5.247 5.455 7.388 4.896 5.437 5.660 7.636 5.082 5.627 5.850 7.893 5.260 5.831 6.067 8.153 5.442 6.020 6.260 8.400 5.629 6.229 6.481 8.676 5.808 6.425 6.673 8.912 6.006 6.635 6.899 9.203 6.200 6.833 7.100 9.460 6.389 7.046 7.314 9.736 6.587 7.250 7.508 9.992 6.779 7.464 7.757 10.272 6.970 7.662 7.952 10.512 7.176 7.888 8.195 10.814 7.375 8.098 8.400 11.175 7.579 8.313 8.639 11.360 7.795 8.545 8.867 11.625 7.989 8.755 9.089 11.911 8.200 8.975 9.300 12.180 8.406 9.196 9.547 12.473 8.617 9.421 9.776 12.747 From Piping Handbook, by Walker and Crocker. This table gives the expansion from -20 F to the temperature in question. To obtain the amount of expansion between any two temperatures take the difference between the figures in the table for those temperatures. For example, if a steel pipe is installed at a temperature of 60 F and is to operate at 300 F, the expansion would be 2.619 -- 0.593 = 1.926 in. will distort the radiators. When expansion strains from the pipes are permitted to reach these light metal heaters they usually emit sounds of distress which are exceedingly troublesome. PIPE THREADS All threaded pipe for heating and ventilating installations uses the American Standard taper pipe thread which is made with a taper of 1 in 335 1 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 16 measured on the diameter of the pipe so as to secure a tight joint. Threads of fittings are tapped to the same taper. The number of threads per inch varies with the different pipe sizes. All threaded pipe should be made up with a thread paste suitable for the service under which the pipe is to be used. . HANGERS AND SUPPORTS Heating system piping requires careful and substantial support. Where changes in temperature of the line are not large, such simple methods of support may be utilized as hanging the line by means of rods or perforated strip from the building structure, or supporting it by brackets or on piers. When fluids are conveyed at temperatures of 150 F or above, however, hangers or supporting equipment must be fabricated and assembled to permit free expansion or contraction of the piping. This can be accom , plished by the use of long rod hangers, spring hangers, chains, hangers or supports fitted with rollers, machined blocks, elliptical or circular rings of larger diameter than the pipe giving contact only at the bottom, or trolley hangers. In all cases, allowance should be made for rod clearance to permit swinging without setting up severe bending action in the rods. For pipes of small size, perforated metal strip is often used. For horizontal mains, the rod or strip usually is attached to the joists or steel work of the floor above. For long runs of vertical pipe subject to con siderable thermal expansion, either the hangers should be designed to prevent excessive load on the bottom support when expansion takes place, or the bottom support should be designed to withstand the entire load. TYPES OF FITTINGS Fittings for joining the separate lengths of pipe together are made in a variety of forms, and are either screwed or flanged, the former being generally used for the smaller sizes of pipe up to and including 3Yi in., and, the latter for the larger sizes, 4 in', and above^ Screwed fittings of large size as well as flanged fittings of small size are also made and are used for certain classes of work at the proper pressure. The material used for fittings is generally cast-iron, but in addition to this nj^lleable iron, steel and steel alloys are also used, as well as various grades''of brass or bronze. The material to be used depends on the character of the service and the pressure. As in the case of pipe, there are several weights of fittings manufactured. Recognized American Standards for the various weights are as follows: Cast-iron pipe flanges and flanged fittings for 25 lb (sizes 4 in. and larger), 125 lb, and 250 lb maximum saturated steam pressure. Malleable iron screwed fittings for 150 lb maximum saturated steam pressure. Cast-iron screwed fittings for 125 and 250 lb maximum saturated steam pressure. Steel flanged fittings for 150 and 300 lb maximum steam service pressure. . The allowable cold water working pressures for these standards vary from 43 lb for the 25 lb standard to 500 lb for the 300 lb steel standard. Screwed fittings include: nipples or short pieces of pipe of varying lengths: couplings, usually of wrought iron only; elbows for turning angles of either 45 deg or 90 deg; return bends, which may be of either the close 336 ' CHAPTER 18. PIPE, FITTINGS, WELDING or open pattern, and may be cast with either a back or side outlet; tees; crosses: laterals or Y branches; and a variety of plugs, bushings, caps, lock-nuts, flanges and reducing fittings. Reducing fittings as well as bushings, both of which are used in changing from one pipe size to another, may have the smaller connection tapped eccentrically to permit free drain age of the water of condensation in steam lines or free escape of air in water lines. Fittings for copper tubing are available in the soldered, flared, or com pression types. Illustrations of each of these types is shown in Fig. 2. Fittings for copper pipe of IPS dimensions are available in screwed or soldered types of connection. The compression type fitting is generally limited to smaller size tubing while the flared and soldered types are used in both large and small sizes. souxK-iYre fitting m ROVIGIRATOB TYPC FURED-TU8MG FITTINGS FLARCO-TUGING FITTINGS Fig. 2. Copper or Brass Tubing Fittings ? ' An American Standard, ASA A40.2-1936 has been prepared to stand ardize dimensions for brass fittings for flared'copper water tubes. : Flared tube fittings are widely used in refrigerating work where SAE dimensions and a 45-deg flare render most fittings interchangeable, although for refrigeration use, thread fits and tolerances on thread gages , must be maintained within close limits. Brass fittings with S.4.E dimensions are not interchangeable with the American Standard fittings for water tubes. Ammonia pipe fittings made of cast-iron were formerly used extensively in handling refrigerants in larger installations. Replacement of ammonia by other refrigerants operating at lower pressures has seriously curtailed the market for these fittings, and the use of copper tubing with special fittings and welded steel piping has further rendered ammonia fittings obsolete. For these reasons formulation of an American Standard for these fittings was abandoned by the ASA in 1936. ; 337 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 is Thread Connections Threads used for fittings are the same American Standard taper pipe threads as those used for pipe, and unless otherwise ordered, right-hand threads are used. To facilitate drainage, some elbows have the thread tapped at an angle to provide a pitch of the connecting pipe of in. to the foot. These elbows are known to the trade as pitched elbows and are commercially available. Malleable iron fittings, like brass fittings, are cast with a round instead of a flat band or bead, or with no bead at all. Fittings are designated as male or female, depending on whether the threads are on the outside or inside, respectively. . . .Flanged fittings are generally used in the best practice for connecting alb piping above 4 in. irii- diameter. "While screwed fittings may be used for the larger sizes arid are satisfactory Under the proper working con ditions, it will be found difficult either to make or to break the joints in these large sizes. , A number of different flange facings in common use are plain face, raised face, tongue and groove, and male and female. Cast-iron fittings for 125 lb pressure and below are normally furnished with a plain face, while the 250 lb cast-iron fittings are -supplied with a H6"'n- raised face. The standard facing for steel flanged fittings for 150 and 300 lb is a }/f6-in. raised face although these fittings are obtainable with a variety of facings. The gasket surface of the raised face may be finished smooth or may be machined with concentric or spiral grooves often referred to as serrated face or phonograph finish, respectively. . The dimensions of elbows, tees and crosses for 125 lb cast-iron screwed fittings are given in Table 7, whereas the dimensions for 125 lb cast-iron flanged fittings are given in Tables 8 and 9. For low temperature service , not to exceed about 220 F, a number of paper or vegetable fiber gasket materials will prove satisfactory; for plain raised face flanges, rubber or rubber inserted gaskets are commonly employed. Asbestos composition gaskets are probably the most widely used, particularly where the temperature exceeds 250 F. Jacketed asbestos and metallic gaskets may be used for any pressure and tem perature conditions, but preferably only with a relatively narrow recessed facing. , WELDING ' Erection of piping in heating and ventilating installations by means of fusion welding has been commonly accepted in the past few years as a competitive method to the screwed and flanged joint. Since the question of economy of welding as against the use of screwed and flanged fittings is dependent on the individual job, the use of welding is generally recom mended on the basis of a greatly reduced cost of maintenance and repair, of less weight resulting from the use of a lighter-weight pipe, and of increased economy in pipe insulation, hangers, and supports rather than 1 on the basis of any economy that might be effected in actual erection by : welding on low to medium pressure heating jobs. Fusion welding, commonly used in erection of piping, is defined as the process of joining metal parts in the molten, or molten and vapor states, without the application of mechanical pressure or blows. Fusion welding 338 . CHAPTER 18. PIPE, FITTINGS, WELDING embraces gas welding and electric arc welding, both of which are cprit- njonly used to produce acceptable welds. f Welding application requires the same basic knowledge of design as do the other types of assembly, but in addition, requires a generous know ledge of the sciences involved, particularly as to welding qualities of metal, their reaction to extremely high temperatures, and the ability to Table 7. Tentative American Standard Dimensions of Elbows, 45-Deg Elbows, Tees, and Crosses (Straight Sizes) for 125-Lb Cast-Iron Screwed Fittings A-H ELBOW 45 ELBOW Nominal P8impe A CENTER To End, Elbows, Tees and Crosses c Center to End, 45 Deo Elbows B. Length op Thread Mm. E. F ........ Width op Band, Mm. Inside Diameter op Fitting . Min. Max. 0H Metal Thickness, Mm. Outside Diameter op Band, Mm. X *4 H V 1 Ui m 2 2M 3 3M 4 5 6 8 10 12 14 O.D. 16 O.D. 0.81 0.95 1.12 1.31 1.50 1.75 1.94 2.25 2.70 3.08 3.42 3.79 4.50 5.13 6.56 8.08 . 9.50 10.40 11.82 0.73 0.80 0.88 0.98 1.12 1.29 1.43 1.68 1.95 2.17 2.39 2.61 3.05 3.46 4.28 5.16 5.97 . ** 0.32 0.36 0.43 0.50 0.58 0.67 0.70 0.75 0.92 0.98 1.03 1.08 1.18 1.28 1.47 1.68 1.88 2.00 2.20 0.38 0.540 0.584 0.44 . 0.675 0.719 0.50 0.840 0.897 0.56 1.050 1.107 0.62 1.315 1.385 0.69 1.660 1.730 0.75 1.900 1.970 0.84 2.375 2.445 0.94 2.875 2.975 1.00 3.500 3.600 1.06 4.000 4.100 1.12 4.500 4.600 1.18 5.563 5.663 1.28 6.625 6.725 1.47 8.625 8.725 1.68 10.750 10.850 1.88 12.750 12.850 2.00 14.000 14.100 2.20 16.000 16.100 0.110 0.120 0.130 0.155 0.170 0.185 0.200 0.220 0.240 0.260 0.280 0.310 0.380 0.430 0.550 0.690 0.800 0.880 1.000 0.93 1.12 1.34 1.63 1.95 .2.39 2.68 3.28 3.86 4.62 5.20 5.79 7.05 8.28 10.63 13.12 15.47 16.94 19.30 All dimensions given in inches. determine and use only the best quality welding rods. This requirement applies equally to employer and employee with the employer accepting all of the responsibility. Thus the employer should select his welding mechanics with good judgment, provide them with first-class equipment and tools, arrange for their training and use of acceptable workmanship standards, and at regular intervals subject their work to prescribed tests. Industry will not accept the employment of mechanics of undetermined! ability nor on the basis of past experience. Neither does industry accept 339 ' HEATING VENTILATING AIR CONDITIONING GUIDE 1940 the statement that a weld is only as good as the workman who makes it. The control Codes now in process of adoption will be the law governing the use of the welding process. These Codes prohibit individual practices contrary to their specified procedure and rules of control, and this is predicated upon the sound requirement that the employer must assume full responsibility for the deposited weld.. It is advisable that this management responsibility be included in all welding specifications and that authoritative standards of workmanship also be specified. The standards of workmanship for this industry are as Table 8. American Standard Dimensions of Tees and Crosses (Straight Sizes) for Class 125 Cast-Iron Flanged Fittings CHAPTER 18. PIPE, FITTINGS. WELDING -et forth in the Standard Manual on Pipe Welding of the Heating, Piping and. Air Conditioning Contractors National Association. A complete line of manufactured steel welding fittings is now available and a dimensional standard is being prepared under the procedure of the American Standards Association to unify heretofore divergent dimensions for the same type welding fittings as produced by different manufacturers. Proposed standard dimensions for elbows, tees, caps, and Iapped-joint stub ends are given in Table 10. Dimensions for eccentric and concentric reducers, and 180-deg return bends are not shown ir Table 10 but will Table 9. American Standard Dimensions of Ei rows for Class 125 Cast-Iron Flanged Fittings Nominal Pin Soisa-b A Center to Fact Tees and CROSSES b-C AA Fact to Fact Tees and Crosses b-c Dujarrzft or Flange Thickness or Flange, Min. METALd Thickness or Boot .i 2 m .3 3X 4 5: 6 8 10 12 . ,14 O.D. 16 O.D. 18 O.D. 20 O.D. 24 O.D, - 30 O.D. 36 O.D. 42 O.D. 48 O.D. 3H 3% 4 4X 5 5H 6 6K 7X 8 9 11 12 14 15 16M . 18 22 25 28 31 34 7 m 8 9 10 11 12 13 15 16 18 22 24 28 30 33 36 44 . 50 56 62 68 4k m 5 6 7 m .9 10 11 nx 16 19 21 23^ 25 27X 32 38K 46 53 MX Ke X Ke X `Ke X - ~-JKe `Ke `Ke 1 IX IKe IX IX IKe IKe l`Ke IX 2X 2X 2X 2X Ke fie Me kfs6 Ke K X Ke X H `.Ke X 1 IKe IX IX IKe ix l`Ke 2 AU dimensions given in inches. - .. . aSize of all fittings listed indicates nominal inside diameter of port. . bTees, side outlettees. and crosses. 16 in. and smaller, reducing on the outlet, have the same dimensions center to face, and face to face as straight size fittings corresponding to the size of the larger opening. Sizes IS in. and larger, reducing on the outlet, are. made in two lengths; depending on the size of the outlet. eTees and crosses, reducing on run only, carry same dimensions center to face and face to face as a straight size fitting of the larger opening. "' - . dBody thickness at no point shalrbe less than 87H per cent-of the dimensions given in the table. .340 Nominal Pipe Size* ABc Center to Fact Elbow b-c-d Center to Fact Lono Radios Elbow b-o-d Center to Face 45 Deo Elbow Diameter or Flange Thickness or Flange, Min. Metal* Thickness or Boot 1 IK IX 2 2X 3m 3X 4 5 6 8 10 12 14 O.D. 16 O.D. 18 O.D. 20 O.D. 24 O.D. 30 O.D. 36 O.D. 42 O.D. 48 O.D. 3X 3X 4 4X 5 5X 6 ex 7X 8 9 11 12 14 15 iex 18 22 25 28 31 34 5 5X 6 ex 7 7X SX 9 10K nx 14 iex 19 21X 24 26 Ki 29 34 41X 49 56X 64 IK 9 2X. 2X 3 3 3X 4 4X 5 5X ex 7X 7X 8 8X 9X 11 15 18 21 24 4K iX 5 6 7 7X 8X 9 10 11 13X 16 19 21 23 X 25 27X 32 38K 46 53 MX Vz Ke % `Ke %A `Ke `Ke `Ke 1 IX IKe lK IX IKe IKe l`Ke IX 2X 2X 2X - 2% Ke Me ?16 Me Mg X Ke 'K K Ke X X `Ke X 1 IKe IX IK IKe IX l`Ke. 2' All dimensions given in inches. . Size of all fittings listed indicates nominal inside diameter of port. ^Reducing elbows and side outlet elbows carry same dimensions center to face as straight size elbows corresponding to the size of the larger opening. Special degree elbows, ranging from 1 to 45 deg, inclusive, have the same center, to face dimensions as given for 45-deg elbows and those over 45 deg and up to flO deg. inclusive, shall have the same center to face dimensions as given for 90-deg elbows. The angle designation of an elbow is its deflection from straight line flow and is the angle between the flange faces. dSide outlet elbows shall have all openings on intersecting center-lines. ' Body thickness at no point shall be less than 87J4 Pr cent of the dimensions given in the table. 341 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 be included in the American Standard. Larger sizes also are available in some types of fittings. The welding bevel which is a straight 3734-deg V for wall thicknesses % in. and below, and a U-bevel for thicknesses heavier than % in., conforms to the recommended practice of .45.4 Standard B16e-1939, American Standard for Steel Pipe Flanges and Flanged Fittings. The latter also contains dimensions for steel welding- neck flanges for pressures up to 2500 lb per square inch. Tables 11 and 12 give these dimensions for welding-neck flanges suitable for 150 and 300 lb per square inch gage pressure. . Socket welding fittings are also commercially available. These fittings have a machined recess into which the pipe slips. A fillet weld between the pipe and socket edge provides a pressure-tight joint. This type of fitting has gained rapid acceptance due to its ease of installation, low cost, and ability to make a pressure tight joint without weakening the pipe as is the case with threading. Standard dimensions for socket welding fittings are being formulated under the procedure of the American Standards Association. Table 10. Proposed American Standard Dimensions for Butt-Welding Elbows, Tees, Caps, and Lapped-Joint Stub Ends Nominal Pipe Size OoTSIDB Diameter i 1% . 1% 2. 2% 3 m 4 5 6 8 10 12 1.315 1.660 1.900 2.375 2.875 3.500 4.000 4.500 5.563 6.625 8.625 10.750 12.750 Cbnteb-to-End 90-Deg Elbows A- 45-Deg Elbows B Of Run Tee Ca i% Vs i% i 2% l % 3m m i% 4% 2 5% 2% 6 2% 7% . 3Vs 9 3% 12 5 15 6% 18 7% i% i% 2% 2% 3 3% 3% 4% 4% m 7 8% 10 C2Jabp-se i% m i% IV, m 2 2% 2% 3 3}4 4 5 6 Lapped-Joint Stub Ends Loigth 4 4 4 6 6 6 6 6 8 8 8 10 10 Radius of met R % Ms y[ Me Me Vs Vs Me Me Vs A A % Plain, of Lap (7d 2 2% 2% 3Vs 4% 5 5% 6Me 7Me 8% 10% 12% 15 All dimensions given in inches. . , The dimensions of welding tees cover those which have side outlets from one size less than half the size of the run-way opening of the tees to full size. . .bDimensions E and F are applicable only to these fittings in schedules up to and including Schedule 80, ASA Standard B36.10-1939. .. oThe shape of these caps shall be ellipsoidal and shall conform to the requirements of the ASME Boiler Construction Code. . dThis dimension is for a regular lapped joint in accordance with ASA Standard B16e-1939.. For ringjoint facing dimensions, see B16e-1939. 342 CHAPTER 18. PIPE, FITTINGS, WELDING VALVES Valves are made with both threaded and flanged ends for screwed.and bolted connections just as are pipe fittings. , The material used for valves of small size is generally brass or bronze for low pressures and forged steel for high pressures, while in the larger sizes either cast-iron, cast-steel or some of the steel alloys are employed. Practically all iron or steel valves intended for steam or water work are bronze-mounted or trimmed. Brass, bronze, and iron valves are generally designed for standard or extra heavy service, the former being used up to 125 lb and the latter up Table 11. American Standard Dimensions of Steel Welding Neck Flanges for Steam Service Pressure Rating of 150 Lb per Sq In. (Gage) at a Temperature of 500 F, and 100 Lb per Sq In. (Gage) at 750 F Nominal Pipe Size A % l 1% ji'A 2 m 3 3% 4 5 6 8! 10 1 124 14(OD 16IOD 18X>D 20pD 24 OD Diameter of Flange Thickness op op Flo.a Min. Diameter op Hub Hub Diam. Beginning OP Champbr*>- Length Thru Hob* Inside Diam. of Pipe Schedule 40o Diam. op. Bolt Circle No. op Bolts 0QX HY J 3% 3Vs 4% 4% 5 6 7 7% m 9 10 11 13% 16 19 21 23% 25 27% 32 Me A Me Vs lMe M Vs 'Me 'Me 1Me 1Me 1 1% lMe 1% i% lMe lMe l'Me - IVs 1%6 1% l'Me 2Me 2Me 3Me 3Me 4% i'Me 3Me 6%e 7Me 9'Me 12 14 A 15% 18 19% 22 26% 0.84 1.05 1.32 1.66 1.90 2.38 2.88 3.50 4.00 4.50 5.56 6.63 8.63 10.75 12.75 14.00 16.00 18.00 20.00 24.00 i% 2Mfi 0.62* 0.82* 2Ms 1.05* 2% 1.38* 2% 1.61* 2% 2.07* 2% 2.47* 2% 3.07* 2'Me 3.55* 3 4.03* 3% 5.05* 3% 6.07* 4 7.98* 4 10.02* 4% 5 To Be 5 Specified 5% by S'Me Purchaser 6 2% 2% 3% 3% 3% 4% 5% 6 7 7% ' 8% 9% 11% 14% 17 18% 21% 22% 25 29% 4 4 4 4 4 4 4 4 8 8 8 8 8 12 12 12 16 16 20 20 Size OP Bolts % % % % % Vs Vs Vs Vs Vs % .% % % Vs 1. 1 1% 1% 1% All dimensions given in inches. ' A raised face of !4 in. is included in thickness of flange minimum and in length through hub. .... . bThe outside surface of the welding end of the hub shall be straight or tapered at not morethan 6 deg. Dimensions H and J correspond to the outside and inside diameters of pipe as given in ASA B36.10- 1939, Schedule 40. , . *These diameters are identical with the diameters of what was formerly designated as Standard Weight Fipe of the corresponding sizes. - -; 343 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 -- i> CHAPTER 18. PIPE, FITTINGS, WELDING to 250 lb saturated steam working pressure, although most manufacturers also make valves for medium pressure up to 175 lb steam working pres sure. The more common types are gate valves or straightway valves, globe valves, angle valves, check valves and automatic valves, such as reducing and back-pressure valves. Gate valves are the most frequently used of all valves since in their open position the resistance to flow is a minimum. These valves may be Table 12. American Standard Dimensions of Steel Welding Neck Flanges for Steam Service Pressure Rating of 300 Lb per Sq In. (Gage) at a Temperature . of 750 F I I secured with either a rising or a non-rising stem, although in the smaller sizes the rising stem is more commonly used. The rising stem valve is desirable because the positions of the handle and stem indicate whether the valve is open or closed, although space limitations may prevent its use. The globe valve is less expensive to manufacture than the gate valve, but its peculiar construction offers a high resistance to flow and may prevent complete drainage of the pipe line. These objections are of particular importance in heating work. Check valves are automatic in operation and permit flow in only one direction, depending for operation on the difference in pressure between Table 13. Standard Roughing-in Dimensions Angle Type Valves Nominal Pipe Gub Dub. op Flange Thice- NZS3 OP Flg. Min. 0Q Dub. OP Hub X Hub Dum. Beginning op Cham- fptb-C-d H Length Thru Hub* Y Inside Duh. op Pipe Schedule 40e d J Inside Dum. op Pipe Schedule 80 d / k K l IK m 2 2K 3 3K 4 5 6 8 10 12 14 OD 16 OD 18 OD 20 OD 24 OD 3K m 4K 5K OK 6K 7K 8K 9 10 11 12K 15 17K 20 K 23 25K 28 30K 36 %6 IK K IK `Me 2K K 2K `Me 2K K 3Me 1 3`Me m 4K 5K IK 5K 1% 7 nu 8K m iok IK 12K 2 14K 2M 16K 2K < 19 2K 21 2 K 23M 2K 27% 0.84 1.05 1.32 1.66 1.90 2.38 2.88 3.50 4.00 4.50 5.56 6.63 8.63 10.75 12.75 14.00 16.00 18.00 20.00 24.00 2Me 2K 2Ke 2Ke 2`Me 2K 3 3K 3Ke 3% 3K 3K 4K 4K 5K 5% 5K 6K 6M m 0.62* . 0.551 0.82* 0.74f 1.05* 0.961 1.38* 1.28| 1.61* 1.50f 2.07* 1.94f 2.47* 2.321 3.07*- --2.901 3.55* 3.36t 4.03* 3.83 f 5.05* 4.811 6.07* 5.76f 7.98* 7.63 f 1_0.02* To Be Specified by Pur- To Be Speci- fied by Pur- chaser chaser Dum. op Bolt Circle No. Size OP op BOLT8 Bolts 2K 4 K 3K 4 K 3K 4 M 3K 4 M 4K 4 M 5 8K 5K 8 K 6K 8 K 7K 8 Vi 7K 8 Vi 9K 8 Vi 10M 12 Vi 13 12 K .15 K 16 1 17K 16 IK 20 kf 20 IK 22K 20 -1% 24% 24 IK 27 24 IK 32 24 IK All dimensions given in inches. ' A raised face of 14 in. is included in thickness offlange minimum and in length through hub. . bThis outside surface of the welding end of the hub shall be straight or tapered at not more than 6 deg. Dimensions H and J correspond to the outside and inside diameters of pipe as given in AS/4 B36.10, 1939. Schedules 40 and 80. Purchaser's order must specify which of these two inside diameters is desired. dThese flanges are' regularly bored to match inside diameter of Schedule 40 pipe, but are bored to Schedule 80 pipe when so ordered. , These diameters are identical with the diameters of what was formerly designated as Standard Weight Pipe of the corresponding sizes. fThese diameters are identical with the diameters of what was formerly designated as Extra-Strong Pipe of the corresponding sizes. 344 fin* OP Valve K K l IK IK 2 Tolerance Dimension A Steam and Hot Water Angle Valves and Union Elbowb Eppbctive Januabt 1.1926 Dimension a Modulating Valves Eppectivb January 1. 1926 Dimension A Return Line Vacuum Valves Effective ' January. 1,1925 2K 2K 3 3K 3K 4K K 2K 2K 3 3K 3K 4K K 3K ..._____ _____ T---- - ........ -- All dimensions given 4n inches. Connecting ends shall be threaded and gaged as to threading according to the American (Taper) Pipe Thread Standard. Af>.A. No. B2--1919. The standardization of the Roughing-in Dimensions of Angle Steam and Hot Water, and Modulating Radiator Valves was made possible by the cooperation of the Manufacturers Standardization Society of the Valves and Fittings Industry. the two sides of the valve. The two principal kinds of check valves are the swing check in which a flapper is hinged to swing back and forth, and the lift check in which a dead weight disc moves vertically from its seat. Valves commonly used for controlling steam or water supply to radi ators constitute a special class since they are manufactured to meet heating system requirements. These valves are generally of the angle type and are usually made of brass. Graduations on the heads or lever handles are often supplied to indicate the relative opening of the valve in any position. Standard roughing-in dimensions for angle-type valves are given in Table 13. ' Automatic control of steam supply to individual radiators can be 345 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 effected by use of- direct-acting radiator valves having a thermostatic element at the valve, or near to it. The direct-acting valve is usually an angle-type valve containing a thermostatic element which permits the flow of steam in accordance with room temperature requirements. These valves usually are capable of adjustment to permit variation in room temperature to suit individual taste. Ordinary steam valves may be used for hot water service by drilling a H6-in. hole through the web forming the seat to insure sufficient circulation to prevent freezing when the valve is closed. Valves made particularly for use in hot water heating systems are of less complex design, one type consisting of a simple butterfly valve, and another of a quick opening type in which a part in the valve mechanism matches up with an opening in the valve body. In one-pipe steam-heating systems, automatic air valves are required at the radiators. Two common types of air valves available are the vacuum type and the straight-pressure type. Vacuum valves permit the expulsion of air from the radiators when the steam pressure rises and, in addition, act as checks to prevent the return of air into the radiator when a vacuum is formed by the condensation of steam after the supply pressure has dropped. Ordinary air valves permit the expulsion of air from the radiator when steam is supplied under pressure, but when the pressure dies down and a vacuum tends to be formed the air is drawn back into the radiator. . A system operating either continuously or intermittently and supplied with vacuum valves will generally hold heat longer and warm up more quickly than one provided with non-vacuum air valves; thus, it will effect considerable economy of fuel because the idle period during which no heat is delivered is shortened. In those cases, ,where a system is equipped with vacuum air valves and which has been cold for several hours, the system will probably have an internal pressure within the radiator closely approaching atmospheric. At such times, the vacuum valve will not vent the system any more rapidly-.than the ordinary type. Automatic air valves are provided with a float to close them in case the radiator becomes flooded with water because it does not drain properly. CORROSION* Corrosion is sometimes encountered in heating work on the outside of buried pipes or the inside of steam heating systems; it is seldom ex perienced in hot water heating systems unless the water is frequently renewed. Piping buried in the ground is quite successfully protected by coatings of the asphaltic type which are usually applied hot and often 'reinforced with fabric wrappings. Galvanizing by the hot-dip process and painting with specially prepared mixtures also afford some protection. Internal corrosion in steam heating systems occurs principally in the *New Light on Heating System Corrosion, by J. H. Walker (Heating and Ventilating, May, 1933). A.S.H.V.E. Research Report No. 983--Corrosion Studies in Steam Heating Systems, by R. R. Seeber. F. A. Rohrman and G. E. Smedberg, (A.S.H.V.E. Transactions. Vol. 40. 1934, p. 253). A.S.H.V.E. Research Report No. 1037--Corrosion Studies in Steam Heating Systems, by R. R. Seeber. F. A. Rohr man and G. E. Smedberg. (A.S.H.V.E. Transactions. Vol. 42, 1936, p. 263). A.S.H.V.E. Research Report No. 1071--Corrosion Studies in Steam Heating Systems, by R: R. Seeber and Margaret R. Holley (A.S.H.V.E. Transactions, Vol. 43. 1937. p. 461). 346 CHAPTER 18. PIPE, FITTINGS, WELDING condensate return pipes and is nearly always caused by oxygen or carbon dioxide, or both, in solution in the condensate. Oxygen may enter the heating system with the steam, owing to its presence in the boiler-feed water, or it may enter as air through small leaks, particularly in systems which operate at sub-atmospheric pressures. When a steam heating system is operated intermittently, air rushes in during each shutdown period and oxygen is absorbed by the condensate which clings to the interior surfaces of the pipes and radiators. The rate of corrosion depends upon the amounts of oxygen and carbon dioxide present in solution, upon the operating temperature, and upon the length of time that the pipe surfaces are in contact with gas-laden condensate. Another possible cause of corrosion is a flow of electric current some times resulting from faulty electrical circuits which should be corrected. Electrolytic corrosion also may occur because of the presence of two dis similar metals, such as brass and iron, but the condensate in practically all steam heating systems is such a weak electrolyte that this cause of corrosion is very, infrequent. If trouble is experienced from corrosion, oxygen should be eliminated from the feed water by proper deaeration with commercial apparatus. The elimination of. the oxygen due to air leakage is more difficult because of the multitude of small leaks which exist around valve stems and in pipe joints. In vacuum systems, however, an attempt should be made to minimize such leakage. Carbon dioxide in varying amounts is contained in steam produced from the majority of water supplies. It is formed from the breaking down of carbonates and bicarbonates which are present in nearly all natural waters. It can be partly removed by chemical treatment and deaeration, but there is no simple method whereby it can be entirely eliminated. These gases cause corrosion only when in solution in the condensate; when they are mixed with dry steam their corrosive effect is negligible. The amount of gas in solution depends upon the partial pressure of that gas in the atmosphere above the surface of the solution, in accordance with the well known physical law of Henry and Dalton*. The exact application of this law, however, assumes equilibrium conditions which do not always exist under the flow conditions prevailing in a heating system. Distinction should be made between corrosion in heating systems proper and in the condensate discharge lines from other apparatus using steam, such as water heaters, kitchen equipment, and sterilizers. Experience has shown that in heating systems the partial pressures of the gases do not reach such magnitudes as to cause harmful amounts of gas to become dissolved in the condensate when steam supplies are of reasonable purity. In other kinds of steam-using apparatus which are not ordinarily well vented, the gases tend to accumulate in the steam space and to become dissolved in the condensate in appreciable concentrations. Consequently, corrosion is frequently observed in the condensate discharge lines from such apparatus, but this does not necessarily indicate that equally serious a Fundamental Considerations of Corrosion in Steam and Condensate Lines, by R. E. Hall and A. R. Mutnford (A.S.H.V.E. Transactions. Vol. 38. 1932. p. 121). 347 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 ,5> corrosion is taking place in the heating system supplied with steam from the same source. When corrosive conditions are believed to exist, their seriousness should be determined by actual measurement, rather than by inference from isolated instances of pipe failures. The National District Heating Associa tion has perfected a corrosion tester for measuring the inherent: corrosive ness of existing conditions. This corrosion tester consists of a frame sup porting three coils of wire which are carefully weighed. After the tester has been inserted in the pipe line for a definite length of time, the loss of weight of the coils, referred to an established scale, indicates the relative corrosiveness of the condensate. Accompanying such corrosion measure ments, a careful chemical analysis should be made of the condensate, and the findings will serve as a basis for an intelligent study of the problem. Corrosion, if found to exist, can be lessened or overcome by several means. If the steam supply is found to be definitely contaminated, proper chemical treatment of the water, followed by deaeration, is an obvious remedy. The leaks in the piping system, particularly in vacuum systems, should be stopped so far as is practicable. . Some success has been reported with the use of inhibitors, chief among which are oil, and sodium silicate. Oil may be fed into the main steamsupply pipe by means of a sight-feed lubricator. The type of oil known as 600-W is usually recommended. In the present state of knowledge on this point, the quantity to be fed can best be determined by trial. The use of sodium silicate, fed in a similar manner, is reported to be successful but it has not been widely used. In view of the fact that corrosion is most frequently found in the return lines from special equipment, which constitute a relatively small part of the total piping in a building, a simple solution of the corrosion problem may be to use non-corroding materials in those certain portions of the piping system, since the higher cost will usually be an unappreciable portion of the total. Brass and copper are undoubtedly less subject to this type of corrosion than the ferrous metals, and considerable attention is now being given to corrosion-resistant linings for ferrous pipe. Cast-iron pipe, sometimes alloyed with other metals, also deserves consideration. 348- Chapter 19 GRAVITY WARM AIR FURNACE SYSTEMS Design Procedure, Estimating Heating Requirements, Leader Pipe Sizes, Proportioning Wall Stacks Register Selections, Recirculating Ducts and Grilles, Furnace Return Connection, Furnace Capacity, Examples, Booster Fans WARM air heating systems of the gravity type are described in this chapter1, and those of the mechanical type are described in Chapter 20. In the gravity type, the motive head producing flow depends upon the difference in weight between the heated air leaving the top of the casing and the cooled air entering the bottom of the casing, while in the mechanical type a fan may supply all or part of the motive head. Booster fans are often used i,n conjunction with gravity-designed systems to increase air circulation. . In general, a warm-air furnace heating plant consists of a fuel-burning furnace or heater, enclosed in a casing of sheet metal or brick, which is placed in the basement of the building. The heated air, taken from the top or sides near the top of the furnace casing, is distributed to the various rooms of the building through sheet metal warm-air pipes. The warm-air pipes in the basement are known as leaders, and the vertical warm-air pipes which are run in the inside partitions of the building are called stacks. The heated air is finally discharged into the rooms through registers which are set in register boxes placed either in the floor or in the side wall, usually at or near the baseboard. The air supply to the furnace may be taken (1) entirely from inside the building through one or more recirculating ducts, (2) entirely from outside the building, in which case no air is recirculated, or (3) through a combination of the inside and the outside air supply systems. DESIGN PROCEDURE The design of a furnace heating system involves the determination of the following items: 1. Heat loss in Btu from each room in the building. 2. Area and diameter in inches of warm-air pipes in bafeement (known as leaders). 3. Area and dimensions in inches of vertical pipes (known as wall stacks). 4. Free and gross area and dimensions in inches of warm-air registers. 5. Area and dimensions of recirculating or outside air ducts, in inches. 6. Free and gross area and dimensions in inches of recirculating registers: lAU figures and much of the-engineering data which follow are from University of Illinois, Engineering Experiment Station Bulletins Nos. 141. 188. 189 and 246; Warm Air Furnaces and Heating Systems, by A. C. Willard; A'. P. Kratz, V. S. Day. and S. Konzo. ' ' 349 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 7. Size of furnace necessary to supply the warm air required to overcome the heat loss from the building. This size should include square inches of leader pipe area which the furnace must supply. It is also desirable to call for a minimum bottom fire-pot diameter in inches, which is the nominal grate diameter. 8. Area and dimensions in inches of chimney and smoke pipe. If an unlined chimney is to be used, that fact should be made clear. The heat loss calculations should be made in accordance with the procedure outlined in Chapter 7, taking into consideration the trans mission losses as well as the infiltration losses. LEADER PIPE SIZES In a gravity circulating warm-air furnace system the size of the leader to a given room depends upon the temperature of the warm air entering the room at the register. A reasonable air temperature at the registers must, therefore, be chosen before the system can be designed. The National Warm Air Heating and Air Conditioning Association has ap proved an air temperature of 175 F at the registers as satisfactory for design purposes. At this temperature, the heat-carrying capacity (heat available above 70 F) per square inch of leader pipe per hour for first, second or third floors is shown by Fig. 1 at 175 F to be 105, 170 and 208 Btu, respectively. For average calculations, the values 111, 166 and 200 will simplify the work and may be satisfactorily substituted for these heat-carrying capacities. If H represents the total heat to be supplied any room, the resulting equations are: H Leader areas for first floor, square inches - = approximately 0.00917 (1) . Leader areas lor second floor, square inches H = approximately 0.00677 (2) H Leader areas for third floor, square inches = approximately 0.00577 (3) In designing for a lower warm-air register temperature, say 160 F, the factors 111, 166 and 200 become 80, 140 and 166 (Fig. 1 at 160 F), and the resulting equations are: Leader areas for first floor, square inches = = approximately 0.01277 oU . (4) H Leader areas for second floor, square inches = = approximately 0.00777 (5) - ' ^ Leader areas for third floor, square inches = -rrr = approximately 0.00677 _ 1 DO (6) These equations are applicable to straight leaders from 6 to 8 ft in length. Longer leaders must be thoroughly insulated or the vertical stacks must be increased in area as discussed under wall stacks. If some provision is not made for these longer leaders, the air temperature may be much lower than anticipated and the room will not be properly heated. The values shown in Fig. 1 apply only to the case where the straight, leader pipe is 8 ft in length and is connected to stacks whose cross-. sectional area is approximately 75 per cent of that of the leader pipe. 350 CHAPTER 19. GRAVITY WARM AIR FURNACE SYSTEMS Any deviation from these conditions requires a modification of the con stants used in Equations 1, 2, and 3. The temperature drop in leaders of various lengths at three different register temperatures is shown in Fig. 2, and should be used to obtain new register temperatures, lower than 175 F, on which to base selections from the curves of Fig. 1, and thereby new constants for Equations 1, 2 and 3. Leader sizes should in general be not less than those obtained by Equations 1 to 3 nor should leaders less than 8 in. in diameter be used. In residences requiring a leader pipe area of 650 sq in. or less, it is advisable to use two or more leader pipes to rooms requiring more than the capacity of a 12 in. round pipe. It is not considered good commercial practice to specify diameters except in whole inches. The tops of all leaders should be at the same elevation as they leave the furnace bonnet, and from this point there should be a uniform up-grade of 1 in. per foot of run in all. casesJj|Leaders over 12 ft in length should be avoided if possible.. In cases where such leaders are required, the use of a larger size pipe, than is required by the application of the equations, smooth transition fittings, and(duct insulation are recommended. 351 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 -5 PROPORTIONING WALL STACKS The wall stack for an upper floor should be made not less than 70 per cent of the area of the leader. In cases where the leader is short and straight as was the case for Fig. 1, such a practice is probably justified, since the loss (Fig. 3) in capacity occasioned by the smaller stack is not serious for stacks having areas in excess of 70 per cent of the leader area. For leaders over 8 ft in length or for leaders which are not straight, the ratio of stack area to leader area should be greater than 70 per cent in CHAPTER 19. GRAVITY WARM AIR FURNACE SYSTEMS REGISTER SELECTIONS The registers used for discharging warm air into the rooms should have a free or net area not less than the area of the leader in the same run of piping. The free area should be at least 70 per cent of the gross area of die register. No upper-floor register should be wider horizontally than the wall stack, and it should be placed either in the baseboard or side wall, if this can be done without the use of offsets. First floor registers may be of the baseboard or floor type, with the former location preferred. High Fig. 2. Influence of Leader Pipe Length on Temperature Loss in Air Flowing through Pipe order to offset the greater temperature losses (Fig. 2) in the longer leader. In gravity circulating systems, this ratio of stack to leader area is a very important matter. The curves in Figs. 4 and 5 indicate that for rooms having a heat requirement exceeding approximately 9000 Btu per hour, exceedingly high register temperatures are required for stacks whose width is less than in. For such requirements either multiple stacks, or stacks having larger cross-sectional area (placed in 6 in. studding spaces) will be required. . 352 Fig. 3. Relative Heating Effect of Stacks at Constant Heat Input to Furnace side wall locations for warm air registers in gravity circulating systems are not recommended on account of the tendency for stratification of the air in the room, resulting in high temperatures at the ceiling. RECIRCULATING DUCTS AND GRILLES The ducts through which air is returned to the furnace should be designed to minimize friction and turbulence. They should be of ample area, equal to or slightly in excess of the total area of warm-air pipes, and 353 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 at all points where the air stream must change direction or shape, stream line fittings should be employed. Horizontal ducts should pitch at least J4 in. per foot upward from the furnace. . The recirculating grilles (or registers) should have a free area at least equal to the ducts to which they connect, and their free area should never be less than 50 per cent of their gross area. The location and number of return grilles will depend on the size, details and exposure of the house. Small compactly built houses may frequently be adequately served by a single return effectively placed in a central hall. More often it is desirable to have two or more returns, provided, however, that in two-story residences one return is placed to effectively receive the cold air returning by way of the stairs. CHAPTER 19. GRAVITY WARM AIR FURNACE SYSTEMS advisable in such ducts. It is important that these ducts be free from unnecessary friction and turbulence, and that they be located to prevent preheating of the air before it reaches the furnace. Furnace Return Connection Circulation of the air is accelerated if the return connection to the furnace is through a round inclined pipe connected to two 45 deg elbows rather than through a vertical pipe connected to two 90 deg elbows. The top of the return shoe should enter the casing below the level of the grate in the furnace. In order to accomplish this the shoe must be wide as is indicated in Fig. 6, No. 1 arrangement. Tests of six different systems of cold air returns, Fig. 6, made at the University of Illinois*, resulted in the following conclusions: Fig. 4. Heating Effect at Registers for Various Stacks with 10-in. Leader Where a divided system of two or more returns is used, the grilles must be placed to serve the maximum area of cold wall or windows.' Thus in rooms having only small windows the grille should be brought as close to the furnace as possible, but if the room has a bay window, French doors, or other large sources of cooling or leakage of cold air, the grille should be placed close by, so as to collect the cool air and prevent drafts. When long ducts of this type are employed they must be made oversize. This precaution is particularly important when long ducts and short ducts are used in the same system. The long ducts must be over size, if they are to operate satisfactorily in parallel with short ducts. Return ducts from upstairs rooms may be necessary in apartments or other spaces which are closed off or badly exposed. Metal linings are 354 EQUIVALENT REGISTER MR TEMPERATVRE*(Treg-T|huT'G5 F) m OEQ F ' Fig. 5. Heating Effect at Registers for Various Stacks with 8-in. Leader 1. In general, somewhat better room temperature conditions may be obtained by returning the air from positions near the cold walls. 2. Friction and turbulence in elaborate return duct systems retard the flow of air, and may seriously reduce furnace efficiency, and lessen the advantages of such a design. 3. The cross-sectional duct area is not the only measure of effectiveness. Friction and turbulence may operate to make the air flow out of all proportion to the various duct areas. FURNACE CAPACITY The size of furnace should, of course, be such as will provide the necessary air heating capacity, usually expressed in square inches of leader pipe area, and at the same time provide a grate of the proper area to burn the necessary fuel at a reasonable chimney draft. The total leader pipe area required is obtained by finding the sum of the leader pipe areas as already designated. 'Investigation of Warm Air Furnaces and HeaUng Systems, Part IV. by A. C. Willard. A. P. Krats, and v. 5. Day (University of Illinois, Engineering Experiment Station Bulletin No. 189). 355 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 .!) The grate area will depend on several factors of which four are very important. First of all, the air temperature at the register for which the plant has been designed must be determined. Usually, this tempera ture is taken at 175 F. Second in importance is the combustion rate, which must always correspond with the register air temperature, as is shown bya set of typical furnace performance curves (Fig. 7) for a cast-iron, circular radiator furnace with a 23 in. diameter grate and 50 in. diameter casing. The third factor is efficiency, which is a function of the'com bustion rate, and varies with it as shown by the efficiency curve of Fig. 7. The fourth factor is the heat value per pound of fuel burned, which was 12,790 Btu. This is not shown on the curves since it was constant for all combustion rates. ' CHAPTER 19. . GRAVITY WARM AIR FURNACE SYSTEMS of the furnace is 62 per cent. Under this condition the capacity at the furnace bonnet per square foot of grate is 43,200 Btu per hour and per sauare inch of grate is 300 Btu per hour, the required area of the grate in ^ 1 25 H ` square inches in this case will be = 0.0042 H. It should be noted that a larger grate area is required if the furnace is to deliver air at a lower register temperature. The typical performance curves shown in Fig. 7 are not applicable to Fig. 6. Arrangement of Cold Air Returns for Six Installations It may be noted from Fig. 7 that for this particular furnace a register temperature of 175 F was accompanied by a combustion rate of approxi mately 7.5 lb per square foot per hour, a capacity at the bonnet of 152,000 Btu per hour and a furnace efficiency of 58 per cent. Under these con ditions the capacity at the bonnet per square foot of grate was equivalent to a value of 52,800 Btu per hour and per square inch of grate was equi valent to 367 Btu per hour. If it is desired to use these curves to select a furnace to deliver air at 175 F register temperature in a house where the total heat loss is H Btu per hour and the loss between the furnace and the registers is 0.25 H Btu per hour, the area of the grate in square inches will be = 0.0034 H. 007 Ifs on the other hand, it is desired to select a furnace to deliver air at 160 F register temperature, the combustion rate is 5.5 lb and the efficiency 356 Fig. 7. Typical Performance Curves for a Warm-Air Furnace and Installation in a Three-Story Ten Leader Plant, Operating on Recirculated Air all furnaces and hence for ordinary design purposes the values recom mended in the Standard Code** should be used. The equation for a furnace having a ratio of heating surface to grate area of 20 to 1 is equal to: G X p X f X Ei X Ei X 0.866 .^Standard Gravity Code for the Design and Installation of Gravity Warm Air Heating Systems in ***dences. This code has been sponsored by the National Warm Air Heating and Air Conditioning Associ~ 'Mton, the National Association of Sheet Metal Contractors, and the American Society of Heating and Ventilating Engineers. It is recommended that the installation of all gravity warm air heating systems ' *k ^dences be governed by the provisions of this code, the tenth edition of which may be obtained from the National Warm Air Heating and Air Conditioning Association, 5 E. Long St., Columbus. Ohio. 357 CHAPTER 19. GRAVITY WARM AIR FURNACE SYSTEMS where G -- grate area, square inch. p = combustion rate, pound coal per square foot of grate per hour. f = heating value of the coal, Btu per pound. Ei = efficiency at bonnet, ratio of heat delivered at bonnet to heat developed in furnace. Ei = efficiency of duct transmission, ratio of heat delivered at register to heat delivered at bonnet. 0.866 = factor of safety to allow for contingencies under service conditions such as accumulations of soot and ashes, ineffective firing methods, etc. H = total heat loss from structure. An addition of 2 per cent of the furnace capacity is proposed for each unit when the ratio of heating surface to grate area exceeds 20. This addition is based on tests4 conducted at the University of Illinois on seven types of furnaces having varying ratios of heating surface to grate area. This correction does not, however, apply to values of the ratio less than 15 nor greater than 30. By transposing the terms in Equation 7 and adding the correction term for ratios of heating surface to grate area other than 20 to 1, the following equation is obtained: . 144 X g pXfXEiXE, X 0.866 [1 + 0.02 (R-20)] (8) in which R = ratio of heating surface to grate area. In the case of the Standard Code6 the numerical values used in Equa tion 8 were based on those determined from the tests conducted on the different types of furnaces. G= 144 X g 7.5 X 12,790 X 0.55 X 0.75 X 0.866 [1 + 0.02 (A-20)]. (9) g G = 0.004205 [1 + 0.02 (.R-20)] (10) As used in these calculations, H = Btu heat loss from the entire house per hour = summation of all room losses Hi + Hi + etc. + the Btu necessary to heat the outside air, if any, at intake. This outside air loss in Btu per hour will be approximately 1.27 times the cubic feet of air admitted through the intake per hour on a zero day. For systems which recirculate all the air this value will be zero. For systems which have an outside air intake, controlled by damper, this value might well be approxi mated, since this loss will probably be reduced to a minimum on a zero day. Assume for such cases that the building loss is increased by 25 per cent, and that there is the usual 25 per cent loss between furnace and registers. TYPICAL DESIGN The application of the preceding data to-an actual example may be of assistance to the designer. Figs. 8, 9, 10 and 11 represent the plans of `University of Illinois, Engineering Experiment Station Bulletin No. 246, by A. C. Willard, A. P. Kratz, and S. Konzo, Chapter X, pp, 126-146. Loc. at. Note 3. 359 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 360 CHAPTER 19. CRAVITY WARM AIR FURNACE SYSTEMS the Warm Air Research Residence of the National Warm Air Heating and Air Conditioning Association erected at the University of Illinois6. Leaders, Stacks and Registers. (Direct Method) Living Room, 1st floor: . 17,250 4- 111 = 155 sq in. leader area. See summary Table 1; also see Art. 3 Sec. 1 of the Standard Gravity Code'. Leader diameter = 14 in. Register size = 155 sq in. net area. Gross area net area 4- 0.7 = 14 in. X 16 in. Owner's Room, 2nd floor: 15,030 4- 167 = 90 sq in. leader area. See summary Table 1; also see Art. 3 Sec. 2 of the Standard Gravity Code'. Leader diameter = 11.4, say 12 in. Stack area =0.7 X 90 = 63 sq in. = say 5 in. X 12 in. Register area =90 sq in. net area. Gross area = net area 4- 0.7 = 12 X 12 or 12 in. X 14 in. In like manner the leaders, stacks and registers are calculated for each room in the house. Leaders, Stacks and Registers. (Code7 Method. See Art. 3, Sec. 1, 2, 3) Living Room (Glass= 90, Net wall = 405, Cubic contents = 2405) .a ( 90 405 2405 \ . Leader " Vl^6 + 57+W;9 = 15Ss,,,n- Register, same as Direct Method. Owner's Room (Glass 68, Net wall = 394, Cubic contents = 2275) .. / 68 , 394 2275 \ ,, . U#**r = (,l2^+57+W;6"9l8<5,n- Stack and Register, same as Direct Method. Assuming all air recirculated, the minimum furnace for the plant will be: Grate area = 0.0042 X 132,370 = 556 sq in. Use 27 in. diameter grate. (Equation 10.) . If provision should be made for certain outside air circulation, then increase the building heat loss by, say 25 per cent and obtain by Equation 10 a 30 in. grate. Experiments at the University of Illinois8 have shown that the capacity of a furnace may be increased nearly three times by an adequate fan, with a constant register or delivery temperature maintained, provided that the rate of fuel consumption can be increased to provide the necessary heat. In other words, the capacity of a forced circulation system is limited by the ability of the chimney to produce a sufficient draft, and the ability of the fan to deliver an adequate amount of air. 'Plans used with permission. Bathroom on third floor not heated. ' ILoc. Cit. Note 3. *University of Illinois. Engineering Experiment Station Bulletin No. 120, p. 129. 361 HEATING VENTILATING AIR CONDITIONING G01DE 1940 Table 1. Summaryof: - Data Applied to Warm,:Air Research Residence Rooms From Chapter 7 Estimating Heat Losses Btu Heat Losses ff Leader . Area . Sq In. Stack. Arei Sq In. 0.7 X LA Leader Diameter Inches Stack Register Size . Size Net. . -. Gross- First Floor 17250 6810 Breakfast..__ 2300 Kitchen--- 9210 Sun...!________ 25710 Hall and stair 12570 Second Floor Owner's_____ 15030 S. W. Bed___ 9800 - Bath.._______ 2450 N. Bed______ 14800 Third Floor E. Bed------ .. . 8220 W. Bed.. 8220 . . = 0.00927 155 -> 61 ' 21 7 83,,... 230...... 113 = 0.00627 90 59 15 . : 89 = 0.00527 41 41 __ _ 63 41 10 7 62 29 29 14 9 8 11 or 12 . Two 12 12 _...__ ___ 14 X 16 8 X 12 8X10 12 X 14 Two 12 X 14 12 X 14' 11 or 12 5 X 12 9 3% X 12 - 8 3 X 10 : 11 or 12 5 X 12 12 X 14 8*12 8X10 12 X 14 8 . 3 X 10 - 8 X 10 8 3 X 10 8 X 10 BOOSTER FANS Booster fans often may be arranged to operate when gas or oil burners are running and to stop automatically when the burners shut down; The booster equipment is most effective in increasing, output; at low operating temperatures. According to tests, efficiencies may be advanced from 60 per cent for gravity td 70 pet cent with boosters at low operating-tem peratures, but at high operating .temperatures gravity and booster efficiencies are almost identical9. ' University of Illinois. Engineering Experiment Station Bulletin No. 141,' p. 79, and No. 246. i 362 Chapter 20 t MECHANICAL WARM AIR FURNACE SYSTEMS Furnaces, Fans and Motors, Sound Control, Sprays and Filters, Air Distribution Design, Automatic Controls, Design of Heat ing System, Selecting the Furnace, Selecting the Fan, Heavy Duty Fan Furnaces, Humidification, Cooling Methods, Cooling . System Design .. .. MECHANICAL warm air or fan furnace heating systems1, which'are a special type of central fan systems, are particularly adapted to residences, small office buildings, Stores, banks, schools; and churches. Circulation of air is effected by, motor-driven fans, instead of by the difference in weight between the heated air leaving/tne'.top .'of the casing apd the cooled air,entering its bottom, as in gravity, systems described in Chapter 19. The advantages of mechanical systems, as cprqpared with gravity systems are: ............... , . . 1. The furnace can be installed in a corner of the basement, leaving more basement room available for other purposes. ': 2. Basement distribution piping can be made, smaller and can be so installed as to give full head room in all parts of the average basement, or be completely concealed from view except in the furnace room. . .. - 3. Circulation of air is positive, and in a properly designed system can be balanced in such a way as to give a greater uniformity of temperature distribution. 4. Humidity control is more readily attained. ," , ,: 5. The air may be cleaned by sprays or filters, or both. . 6. The fan and duct equipment may be utilized for a complete cooling arid dehumidi- fying system for summer, using either ice, mechanical refrigeration, or low temperature water for cooling and dehumidifying, or adsorbers for dehumidifying. - 7" 7. The use of the fan increases the volume of air which can- be handled, thereby increasing the rate of . heat extraction from a given amount of heating surface and insuring sufficient air volume to obtain proper distribution in a large room. ... 7 Much of the equipment used in central fan systems is the subject matter of other chapters. It is. the purpose of this chapter to discuss the co ordinated design and to deal in detail only with problems not covered elsewhere which refer particularly to the whole problem of fan warm air furnace heating and air conditioning. ; . lSee University of Illinois, Engineering Experiment Station Bulletin No. 266 by A. P. Kratz and S. Konzo tor details of tests conducted in Warm Air Research Residence. 363 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 FURNACES Furnaces for mechanical warm air systems may be made of cast-iron, steel, or alloy. Cast-iron furnaces are usually made in sections and must be assembled and cemented or bolted together on the job. Steel furnaces, are made with welded or riveted seams. The proper design of the furnace depends largely on the kind of fuel to be burned. Accordingly, various manufacturers are making special units for coal, oil and gas. Each type of fuel requires a distinct type of. furnace for highest efficiency and econ omy, substantially as follows: 1. Coal Burning: a. Bituminous--Large combustion space with easily accessible secondary radiator or flue travel. b. Anthracite or coke--Large fire box capacity and liberal secondary heating surfaces. 2. Oil Burning: a. Liberal combustion space. b. Long fire travel and extensive heating surface. 3. Gas Burning: a. Extensive heating surface. b. Close contact between flame and heating surface. A combustion rate of from 5 to 8 lb of coal per square foot of grate per hour is recommended for residential heaters. A higher combustion rate is permissible with larger furnaces for buildings other than residences, depending upon the ratio of grate surface to heating surface, firing period, and available draft. . Where.oil fuel is used, care must be exercised in selecting the proper size and type of burner for the particular size and type of furnace used. It is recommended that the system be designed for blow-through installations, so that the furnace shall be under external pressure in order to. minimize the possibility of leakage of the products .of combustion into the air circulating system.. . In residential furnaces for.coal burning, the ratio of heating surface to grate area will average about 20 to 1; in commercial sizes it may run as high as 50 to 1, depending on fuel and draft. Furnaces may be installed singly, each furnace with its own fan, or in batteries of any number of furnaces, using one or more fans. Furnace Casings Casings are usually constructed :of galvanized iron, 26-gage or heavier, but they may also be constructed of brick. Galvanized iron casings should be lined with sheet iron liners, extending from the grate level to the top of the furnace and spaced from 1 in. to in. from the outer casing. Casings for commercial or heavy duty furnaces, if-built of galvanized iron, should be insulated with fireproof insulating material at least 2 in. thick. It is generally believed that either brick or sheet metal casing should be equipped with baffles to secure impingement of the air to be heated against the heating surfaces. Brick furnace casings should be supplied with access doors for inspection. "For furnace casings sized for gravity flow of air, where a fan is to be 364 CHAPTER 20. MECHANICAL WARM AIR FURNACE SYSTEMS used, some form of baffling must be employed if the desired results are to be expected. Many manufacturers recommend the use of special baffles to restrict the free area within the casing and to force impingement of the air against the heating surfaces. A method for making these baffles for furnaces with top horseshoe radiators and for furnaces with back crescent radiators is illustrated in Fig. 1. Either square or round casings may be used. Where square casings are Fig. 1. Usual Method of Baffling Round Casings for Fan Furnace Work A. Liner. 1 in. from casing. B. 1 Hole to vent baffle. C. Baffle* closed top and bottom. D. Outer pairing Fig. 2. Method of Baffling Square Furnace Casing for Fan Furnace Work . A. Baffle, closed top and bottom. B. Liner. 1 in. from casing. C. Outer casing. D. Hole to vent baffle. ' - used, the corners must be baffled to reduce the net free area and to force impingement of air against the heating surfaces. Fig. 2 shows a satis factory method of baffling square furnace casings for fan furnace work. The hood or,, bonnet of the casing above the furnace should be as high as basement conditions will allow, to form a plenum chamber over the top of the furnace. This tends to equalize the. pressure and temperature of the air leaving the bonnet through the various openings. It is generally, con sidered advisable to take off the warm air pipes from the side of the bonnet near the top, as this method of take-off allows the use of a higher bonnet 365 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 and thus provides a larger plenum chamber. Fig. 3 illustrates a complete residence fan furnace installation showing location of fan, furnace, filters, plenum chamber and method of take-off of warm air pipe. FANS AND MOTORS Centrifugal type fans are most commonly, used, and these may be equipped with either backward or forward curved blades. Motors may be mounted on the fan shaft or outside of the fan with belt connection. Multi-speed motors or pulleys are desirable to provide a factor of safety and to allow for increased air circulation. For additional information on fans and motors, see Chapters 28 and 39. ' Special attention should be given to the problem of noise elimination. The fan housing should not be directly connected with metal, either to the furnace casing or to the return air piping. It is common practice to. use canvas strips in making these connections. Motors and their mountings must be carefully selected for quiet operation. Electrical conduit and water piping must not be fastened to, nor make contact with fan housing. The installation of a fan directly under a cold air grille is not recommended on account of the noise objection. (See also Chapter 31.) FILTERS There are many satisfactory types of filters on-the market. These include dry filters, viscous filters, oil filters and other types, some of which must be cleaned, some of which must be cleaned and recharged with oil, and some of which are inexpensive and may be discarded when they become dirty, and replaced with new ones. ' . 366 CHAPTER 20. MECHANICAL WARM AIR FURNACE SYSTEMS The resistance of a filter must be considered in the design of the system since the resistance rises rapidly as the filter becomes dirty, thus im pairing the heating efficiency of the furnace, in fact, endangering the life of the furnace itself. Manufacturers' ratings of filters must be carefully regarded, and ample filter area must be provided. Filters must be replaced or cleaned when dirty. (See also Chapter 27.) AIR DISTRIBUTION The conditions of comfort obtained in a room:are greatly influenced by the type of register used and the locations of the supply registers and return grilles. In general it has been found that changes in the type, air velocity, and location of the supply register affect the room conditions much more than the changes in the location of the return grilles. Due to the economic considerations involved, it is common practice to locate the supply openings on the inside walls of a residence and the return openings nearest the greatest outside exposure. ' Many designers prefer, however, to locate the supply registers so that the warm air from the registers blankets a cold wall, and mixes with the cold air dropping off from the exposed walls. This may be accomplished by the use of a supply register placed close to an outside wall in such a position that the warm air sweeps the cold wall surface. The ducts leading to supply registers which are located ort exposed walls should be adequately insulated to reduce the heat loss from the ducts. Register and Grille Openings Supply registers located-in the floor are effective, but as they require frequent attention to keep them clean they should be avoided where another effective register location can be found. .Tests conducted in the Warm Air Research Residence2 have indicated that excellent results are obtainable with either high side wall or baseboard registers, providing a reasonable amount of precaution is employed. Baseboard registers should be of a deflecting-diffuser type which throws the air downward toward the floor and diffuses it at the same time. Register air tempera tures under 125 F and air velocities over 500 fpm should be avoided as they may cause drafts. High side wall registers must be of such type that the air is delivered horizontally or in a slightly downward direction, and must be so located as to avoid impingement of air on ceiling or wall. Directional flow diffusing type should be used to insure best results. Register air velocities should be such that the air stream carries to' the opposite exposure. Velocities under 500 fpm are not recommended. Register air tempera tures under 125 F are not objectionable. In fact, when cooling is desired, better air distribution is obtained with high side wall registers. Unless registers, regardless of their location, are well proportioned and designed as well as decorated to harmonize with the trim, they , may be unsightly. All registers should be equipped with dampers and must be sealed against leakage around the borders or margins. Loc. Cit. Not* 1. 367 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Velocities through registers may be reduced by the use of registers larger than the connecting pipes. Some suggestions for equalizing veloci ties over the face area of the register by means of diffusers are illustrated in Fig. 4. Merely to use a larger register may not result in materially reduced velocities unless diffusers are used. Fig 4 `` Diffusers in Transition Fittings to Equalize Velocities through Register Faces Dampers Suitable dampers are essential to any trunk or individual duct system, as it is virtually impossible to so lay out a system that it will be absolutely in balance without the use of dampers. Special care must be used in the design of any system to avoid turbulence and to minimize resistance. Sharp elbows, angles, and offsets should be avoided. (See Figs. 1 and 2, Chapter 30.) Fig. 5. Three Types of Dampers Commonly Used for Trunk and Individual ' Duct Systems Three types of dampers are commonly used in trunk and individual duct systems. Volume dampers are used to completely cut off or reduce the flow through pipes. (See A and B, Fig. 5.) Splitter dampers are used where a branch is taken off from a main trunk. (See C, Fig. 5.) Squeeze dampers are used'for adjusting the volume of air flow and resistance through a given duct. (See D, Fig. 5.) It is essential that a damper be provided for each main or duct branch. A positive locking device should be used with each type of damper. 368 CHAPTER 20. MECHANICAL WARM AlR FURNACE SYSTEMS Ducts The ducts may be either round or rectangular. The radii of elbows should be not less than one and one-half times the pipe diameter for round pipes, or the equivalent round pipe size in the case of rectangular ducts. AUTOMATIC CONTROLS Air stratification, high bonnet temperatures, excessive flue gas tem peratures, and heat overrun or lag in a properly designed system can be largely eliminated through proper care in the planning and installation of the control system3. The essential requirements of the control are: 1. To keep the fire burning when using solid fuel regardless of the weather. 2. To avoid excessive bonnet temperatures with resultant radiant heat losses into the basement. 3. To avoid the overheating of certain rooms through gravity action during off periods of blower operation. 4. To have a sufficient supply of heat available at all times to avoid lag when the room thermostat calls for heat. 5. To prevent cold air delivery when heat supply is insufficient. 6. To avoid heat loss through the chimney by keeping stack temperatures low. 7. To provide quick response to the thermostat, with protection against overrun. 8. To provide for humidity control. 9. To provide a means of summer control of cooling. 10. To protect against fire hazards. The following controls are desirable: 1. A thermostat located at a point where maximum fluctuation in temperature can be expected, in order to secure frequent operation of fans, drafts, and burners. This location would be near an outside wall but not upon it, in a sun room, or in a room with some unusual exposure. The thermostat, of course, should not be located where it will be affected by direct radiant heat from the sun or from a fireplace, or by direct heat from any warm air duct or register. 2. A thermostatic blower switch located in the bonnet to permit blower operation only between the temperatures of 100 F and 150 F. In certain extreme cases it may be necessary, or weather conditions may make it advisable, to adjust the high limit to a higher temperature than that given. Another location sometimes used for the blower switch is in the main duct near the frame opening from the bonnet. -. 3. A protective limit control located in the bonnet to shut down the system inde pendently of the thermostat if the bonnet.temperature exceeds 200 F. 4. On oil and gas burner installations, a control should be included which will shut down the system if the fire goes out or if there is a failure of the ignition'system.. 5. A humidistat to regulate the moisture supplied to the rooms. 6. On automatic stoker installations, a control is usually included which will start the operation regardless of thermostat settings whenever. the bonnet temperature radicates that the fire is dying, or a time interval contactor is used that will start the stoker to run a predetermined length of time at predetermined intervals. METHOD OF DESIGNING FORCED-AIR HEATING SYSTEMS 1. Determine heat loss from each room in Btu per hour. (See Chapter 7.) 2. Locate warm air registers and return registers on plans of house, beginning with the upper story rooms. Automatic Controls for Foreed-Air Heating Systems, by S. Konzo and A. F. Hubbard (A.S.H.V.E. Transactions, Vol. 40. 1934. p. 37). ....................... , 369 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 3. Sketch in duct layout to connect all registers and grilles with the central unit. 4. Determine equivalent length of duct for each register, allowing 10 diameters of straight pipe as equivalent to each 90 deg elbow having an inner radius not less than the diameter of the round pipe or the depth of the rectangular pipe. - 5- Select a value for temperature of the air at the furnace bonnet. It is customary to use some value lying between 150 to 165 F. Use lower value if larger number of air recirculations is desired. It is recommended that the number of air recirculations should be in excess of 5 per hour. 6. Determine approximate value of temperature reduction in each duct caused by . heat loss from the ducts. A value of from 0.3 to 0.6 F per foot of duct has been obtained from tests conducted in the Research Residence installation for uninsulated duct lengths up to approximately 60 ft. " - 7. Subtract this temperature reduction from the assumed bonnet air temperature to obtain an approximate value of the register air temperature for each register. 8. Determine the required air volume for each room from the following equation, or from the values listed in Table 1: H 60 X 0.24 X d \tt - 65) (1) where Q -- required air volume, cubic feet per minute. H -- heat loss of room, Btu per hour. . d = density of air at register temperature, pounds per cubic loot. It -- register temperature, degrees Fahrenheit. 0.24 -- specific heat of air. ' 65 = return air temperature. For any given register temperature the solution of this equation simplifies to the following form: , Q = R X Factor (2) in which the values of the Factor may be obtained from Table 1. 9. Determine register size from the air volume delivered to each room by the following formula: Free area of register, square feet -- y (3) Free Area Gross area of register, square feet = (4) where Q -- required air volume, cubic feet per minute. V = velocity at register lace, feet per minute. R = ratio of free area to gross area of register. Table 1. Factors Corresponding to Register Temperature for Equation 2 Rggrypia TeKPEBAYCBS Factob no 120 130 140 150 0.0221 0.0184 0.0158 0.0140 0.0125 0.0114 160 170 0.0105 370 CHAPTER 20. MECHANICAL WARM AIR FURNACE SYSTEMS Allowable register velocities to be used in Equation 3 are approximately as follows: ; Baseboard, non-deflecting type, maximum = 300 fpm. Baseboard, deflecting toward floor, maximum = 500 fpm. Baseboard, deflecting and diffusing = up to 800 fpm. . : . : High side wall = not less than 500 fpm. :. iO. Duct systems for forced-air installations may consist of either trunk systems or individual duct systems. '" , ------------- ----...v '---I. incuon losses as outlined in Chapter 30; except that for residence applications the velocities in the main duct and in the various parts of the system should approximate the values recommended in Table 2. Individual Duct Systems. An individual duct system is one having separate ducts extending from the heating unit to each register. In designing such a system select first the duct having the greatest equivalent length. Select a reasonable velocity using Table 2 as a guide. From friction chart in Chapter 30 determine unit frictionToss per 100 ft of run, and from this the total friction loss in the duct selected. If this total friction loss exceeds a reasonable value a lower velocity should be used. The remaining ducts are proportioned so that the total pressure in each duct is the same as that calculated for the longest duct. The added resistance necessary in the shorter ducts is accomplished by increasing the velocity in these ducts. No duct should be less than 6 in. in diameter, nor should the velocity in any duct exceed approximately 1200 fpm. The final adjustment in a duct system may be made by employing dampers. Table 2. Recommended Velocities through Ducts and Registers . Description Low Velocity System (fpm) Mam ducts..................... Branch ducts... ............. Wall stacks. ........... Baseboard registers (max.Y Wall registers above 5 ft (min.),,....... 500 450 350 300 500 Medium Velocity System (fpm) High Velocity System . (mt) . 7o0 oUU 550 1000 /OU 600, . 400 600 ___ j_____--jj (ivuuginpu is ia more usual tn practice to proportion all the ducts so that they have the same velocity as that used in the longest duct and to balance the system by employing dampers in the shorter ducts. Return duct systems are designed making use of the same principles as those used in the design of supply duct systems. In this case the design may be based on the volume of air corresponding to the'density of air existing in the return ducts, or in order to provide a factor tor air leakage, it may be based on the same volume as used for the supply ducts. 11. Determine frictional resistance in: . ; a. Supply side of system as outlined in Item 10. i. Return side of system as outlined in Item 10. c. Furnace units, casing or hood, which is usually considered as equivalent to 0.03 ( . to 0.10 in. of water. , ,, d. Accessories such as washers or air filters, from manufacturer's data. e. Inlet and outlet registers and grilles, from manufacturer's data. /. Other accessory equipment such as cooling coils, from manufacturer's data.. Choose a fan which, according to its manufacturer's rating, is capable of delivering a volume of air, expressed in cubic feet per minute, against a frictional resistance, expressed! m inches of water, computed by adding together the items listed in the preceding discus sion. In practice it is recommended that liberal allowances should be made so that the; 371 K HEATING VENTILATING AIR CONDITIONING GUIDE 1940 fan will be capable of delivering air against pressures that may not have been foreseen during the design of the duct system. 12. Select a furnace capable of delivering heat at the register outlets equal to the total heat loss of the structure to be heated. The following formula may be used for coal burning furnaces: .. ' G = fXpX Ei X . [1 + 0.02 (R - 20)] (5) where G = required grate area, square feet. H -- total heat loss from building, Btu per hour. / = calorific value of coal, Btu per pound. p = combustion rate in pounds of fuel per square foot of grate per hour. Ei = furnace efficiency based on heat available at bonnet. Ei -- efficiency of transmission based on ratio of heat delivered at register to heat available at bonnet. . R = ratio of heating surface to grate area. In practice it is customary to use the following constants: / = 12,000 (for specific values, see Table 5, Chapter 9). p = 7.5 lb. Ei = 0.65 lower efficiency must be used with highly volatile solid fuel. , = 0.85. The foregoing procedure for determining the size of the furnace to be used applies to continuously heated buildings. 13. Although intermittently heated buildings usually have their heat losses computed according to the standard rules for determining such losses, these rules do not take into account the heat which will be absorbed by the cold material of the building after the air is raised in temperature. This heat absorption must be added to the normal heat loss of the building to determine the load which the heating plant must carry through the warming-up process. It is customary to increase the normal heat loss figure by from 50 to 150 per cent depending upon the heat capacity of the construction material, the higher percentage applying to materials of high heat capacity, such as concrete and brick. Fan furnace systems are well adapted for heating intermittently heated buildings as these systems do not require the warming of intermediate piping, radiators, or convectors, the generation of steam, or the heating of hot water. . 14. Follow the same methods for an oil furnace as for coal where a conversion unit is to be used, making sure that the ratio of heating surface to grate area exceeds 20 to 1. If it does not, a size larger furnace should be selected. Use the manufacturer's Btu ratings of furnaces designed for exclusive use with oil, and select a burner with liberal excess capacity. 15. The selection of the proper size gas furnace for a constantly heated building can ' be easily made by using the following American Gas Association formula: ' where H = total heat loss from building, Btu per hour. R = official A.G.A. output rating of the furnace, Btu per hour. In the case of converted warm air furnaces a slightly different procedure is necessary, as-the Btu input to the conversion burner must be selected rather than the furnace out put: ' The proper sizing may be done by means of the following formula: ' V ,V ' . I = 1.59 H ~ (7) 372 CHAPTER 20. MECHANICAL WARM AIR FURNACE SYSTEMS where I = Btu per hour input. The factor 1.59 is the multiplier necessary to care for a 10 per cent heat loss in the distributing ducts and an efficiency of 70 per cent in the conversion burner. 16. Specify location and type of all tampers in both supply air and return air sides of system. Specify controls including location of all thermostats. Arrange for proper control of humidifying equipment. ' HEAVY DUTY FAN FURNACES Fan furnaces for large commercial and industrial buildings are available in sizes ranging from 400,000 to 3,000,000 Btu per hour per unit. Heavy duty heaters may .be arranged in combinations of one or more units in a battery. One typical arrangement is shown in Fig. 6. Most manufacturers of heavy duty furnaces rate their furnaces, in Btu per hour and also in the number of square feet of heating surface. Con 'I1I------------------:------------------- r . Fig. G. Heater Arrangep for Use of Air Washer or Filter (A) with Heated Air to Mix with Outside Air for Tem pering, showing Mixing Damper from Warm Air and Tempered Air and Exhaust to Atmosphere servative practice indicates that at no time in the heating-up- period should the furnace surface be required to emit more than an average of 3500 Btu per square foot. A higher rate of heat emission tends to increase the heat loss up the chimney, and raise fuel consumption, to shorten the life of the furnace, and to overheat the air. The ratio of heating surface to grate area on furnaces for this type of work should never be less than 30 to 1 and as indicated previously may run as high as 50 to 1. Control of temperature is secured through (1) controlling the quantity of heated air entering the room, (2) using mixing dampers, or (3) regu lating the fuel supply. The design of heavy duty fan furnace heating systems is in many respects similar to that of the central fan heating systems described in Chapter 21. Ducts are designed by the method outlined in Chapter 30. HUMIDIFICATION Mechanical warm air systems offer a means of proportioning and distributing moisture-bearing air; consequently, during the winter months 373 HEAT1NC VENTILATING AIR CONDITIONING CUIDE 1940 humidifiers may be employed to deliver water vapor to the fan-driven air stream in proper amounts to produce a more humid .atmosphere; with increased comfort for people and increased life for household furnishings. Temperatures and .relative humidities should be governed .'within the limits of the generally "accepted standards. See Chapters 3 and 26 for . more detailed information on this point. . , In earlier types of furnaces, water evaporating pans were usually placed in the cool portions of the air stream, but modern types usually locate them in air which has been heated by contact with the heating surfaces. To change water into vapor capable of being carried in an air stream as part of the mixture, about 1000 Btu per pound are required. Without the addition of this heat; termed the latent heat of evaporation, water injected into the air will be carried along in the form of tiny globules until it falls out of the stream or is deposited upon some surface. Furthermore; when dry air is in contact with water for a sufficient length of time without the presence of :a sizable body of water or a .source other than air from which this latent heat of evaporation can be taken, such heat is supplied from the air. There is, therefore, a trend in present practice toward heating the water in addition to-heating the air. Equipment for doing this may make use of sprays, or it may take the form of water Circulating coils placed within the combustion chamber and connected by pipes to the humidifier pans where a constant water level is maintained by some separate float device. (See Chapter 26.) . Sprays for residence systems may be provided in separate housings to be installed on the inlet or outlet side-of the fan, or they may be integral with the fan construction. They operate at water pressures of from 10 to 30 lb and use two-or more spray nozzles for washing and humidification. The sprays should be adjusted to completely cover the air passages. ;........................ ............... . Sprays are usually controlled by solenoid; valves wired in parallel with the fan motor., The water,supply may, in turn, be controlled by a humidity-controlling device located in one of the living rooms, so that the washer will operate at all times when the fan is in operation, unless the relative humidity should rise beyond a desirable percentage. Sprays used in connection with commercial or heavy duty plants should be a regulation type of commercial spray. '1 Residence Requirements ! The principles underlying humidity requirements and limitations for residences are summarized., in University of Illinois Bulletin No. 230V as follows: . .. . 1. Optimum comfort is the most tangible criterion for determining the air conditions within a residence. 2. An effective -temperature of 65 deg5 represents the optimum comfort-dor the majority of people:. Under the conditions in the avgrage:residence a dry-bulb,teynperar ture of 69.5 F with relative humidity of 40 per cent is the most practical for the attain ment of 65 deg effective temperature. `See Humidification for Residences, by A. P. KraU (University of IUinois, Bulletin No. 230). 66 deg is the optimum winter.effective temperature recommended by the A.S.H.V.E. Committee on Ventilation Standards. v ; -" 374 CHAPTER 20.-'-MECHANICAL WARM AIR FURNACE SYSTEMS 3. Evaporation requirements' to maintain a relative humidity of 40 per cent In zero weather depend on the amount of air inleakage to the average residence, and vary from practically nothing, to 24 gal of water per 24 hr. . . 4. Relative humidity of 40 per cent indoors cannot be maintained in rigorous climates without excessive condensation on the windows unless tight-fitting-storm sash or the equivalent is installed. 5. The problems of humidity requirements and limitations cannot be separated from condensations of good building construction, and the latter should receive serious attention in the installation of humidifying apparatus. The following conclusions were drawn from the experimental results reported in the aforementioned bulletin: / 1. None of the types of gravity warm air furnace water pans-tested proved adequate to evaporate sufficient water to maintain 40 per cent relative humidity in the Research Residence except only in moderately cold weather. 2: The water pans used in the radiator shields tested did not prove adequate to maintain 40 per cent relative humidity in a residence similar to the Research Residence when the outdoor temperature approximated zero degrees Fahrenheit; COOLING METHODS A slight cooling, effect may be obtained under certain, conditions by the use of basement air. A more positive cooling effect may be obtained through air washers where the temperature, of the water is sufficiently low (55 F or lower), and where a sufficient volume of water can be pro vided. Unless the temperature of the leaving water is below the dew point temperature of the indoor air at the time the washer is started, both the relative and absolute humidities will be somewhat increased. Coils of copper finned tubing through which cold water is pumped are available for cooling. They require less space than air washers and have the advantage that no moisture is added to the air when the temperature of the water rises above the dew-point. Ample coil surface is necessary with this type of cooling: It is thoroughly feasible to use ice or mechanical refrigeration in con nection with the fan and duct system for the heating installation, and to cool the building by this method, provided the building is reasonably well constructed and insulated. Windows and doors should be tight, and awnings should be supplied on the sunny side of the building. (See also Chapters 21 and 24.) - Results at Research Residence The following conclusions may be drawn from the studies thus far completed in the Research Residence, subject to the limitations of the conditions under which the tests were run6: . 1. An uninsulated building of ordinary residential type may require the equivalent of three tons of ice in 24 hr on days when the maximum outdoor temperature reaches 100 F if an effective temperature of approximately 72 deg is maintained indoors. 2. The use of awnings at all windows in east, south, and west exposures may result in savings of from 20 to 30 per cent in the required cooling load. TI `A.S.H.V.E. Research Report No. 947--Study of Summer Cooling in the Research Residence at the Umvernty of Illinois, by A. P. KraU and S. Konso (A.S.H.V.E. TbInsact.0ns Vo1;i9 1333 p 95) A.S.H.V.E. Research Report No. 979--Study of Summer Cooling in the Research Residence-for the Summer of 1933. by A. P. KraU and S. Konzo (A.S.H.V.E. Transactions. Vol. 40, 1934, D? 167). 375 / ________________________________________ HEATING VENTILATING AIR CONDITIONING GUIDE 1940 3. The cooling load per degree difference in temperature is not constant but increases as the outdoor temperature increases. 4. The heat lag of the building complicates the estimation of the cooling load under any specified conditions and makes such estimates, based on the usual methods of computation, of doubtful value. ' 5. The seasonal cooling requirements are extremely variable from year to year, and the ratio between the degree-hours of any two seasons occurring within a 10 year period may be as high as 7.5 to 1. Hence an average value of the degree-hours cooling per season is comparatively meaningless. 6. The duct system in a forced-air heating installation can be successfully converted to a system for conveying cool air for the purpose of cooling the structure. No conden sation of moisture was observed when' the duct temperatures were not less than 65 F. 7. Cooling by means of water at a temperature of 60 F is not satisfactory unless an indoor temperature of less than 80 F is maintained. 8. In the selection of cooling coils, the frictional resistance of the coil to flow of air must be given careful consideration. 9. Cooling the structure by introducing large quantities of air from outdoors at night tended to reduce the amount of cooling required on the following day and was a practical means of providing more comfortable conditions in those homes where cooling systems were not available. METHOD OF DESIGNING COOLING SYSTEM The general procedure for the design of a-cooling system in a forced-air installation is as follows: 1. Calculate heat gain for each room or space to be conditioned. (See Chapters 5 and 8.) Allowance for addition of outside air must be included in this calculation. . 2. Select a temperature of air leaving supply inlets. In. Research Residence tests7 a value of from 65 to 70 F was found satisfactory. 3. Determine indoor conditions to be maintained. In Research Residence 80 F dry- bulb and 45 per cent relative humidity was found satisfactory. ' 4. Determine the quantity of air to be introduced into each room. (See Chapter21.) . 5. Estimate heat loss in duct system between cooling unit and supply registers. 6. Calculate the heat to be removed by the cooling unit, in the form of sensible heat and latent heat. 7. .Determine size of ducts in duct system and'size of registers, as explained in this chapter under the heading of Method of Designing Forced-Air Heating Systems. '. 8. Determine pressure loss in duct system and select fan as; also explained in the same section. 9. Select cooling unit from manufacturer's data. Specify temperature and pressure of available cooling water, voltage and characteristics of electrical supply, and method of control of apparatus. <. 10. Select cooling coils from manufacturer's data to take care of latent heat load and to give required drop in air temperature with the weight of air flowing. (See Chapter 25.) . 11. If system is to be used for both winter heating and summer cooling, duct sizes must be checked to insure that velocities and friction losses are reasonable for both conditions of operation. Adjustable dampers will be necessary to make changes in air distribution for the two seasons. Provision must also be made for changing fan speeds for summer and winter operation. Chapter 21 CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING Types of Systems for Heating, Humidifying, Cooling, Dehumodifying with Modifications, Design Details, Load Calcula- tions, Selection of Equipment THE purpose of this chapter is to offer a summary of the procedure generally followed in the design of central systems for comfort air conditioning. Detailed information for making the various calculations is found elsewhere in The Guide, and reference to the proper chapter follows in this text. The reader is also referred to the Code of Minimum Requirements1, which was prepared by a joint Committee of the American Society of Heating and Ventilating Engineers and the American Society of Refrigerating'Engineers, and which was adopted by the Society in January 1938. Engineers should also be familiar with any state or municipal codes which may apply to the problem under consideration. A central system consists of a fan with complete supply and return ducts designed to serve one or more conditioned spaces, together with someor all of the following equipment: heating coils, cooling coils, humidi fiers,'dehumidifiers, air cleaning devices, and control equipment. These various items of equipment are assembled into a properly balanced system which has for its purpose the control of temperature and humidity within the conditioned space. The principal types of central systems are illustrated in Figs. 1 to 5, but space does not allow showing all of the modifications to which these types may be subjected by the conditions existing in the building or by the preferences of the designing engineer. Also, a central system need not provide for year-round conditioning, but may be designed only for heating, cooling, or simply for ventilation. CLASSIFICATION OF SYSTEMS Central systems in which dehumidification is accomplished by cooling may be classified as follows: . 'Code of Minimum Requirements for Comfort Air Conditioning (A.S.H.V.E. Transactions, Vol. 44, 1938,-p. 27). Reprints of this code are available at $.10 a copy. 377 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 1. Central system with heating and cooling coils and humidifying sprays (Fig. i) This system is very common and used extensively for summer and winter conditioning! 2. Central system with preheating coil, washer and reheating coil (Fig. 2). This is widely used for winter conditioning on larger installations. Summer conditioning is accomplished by using cold water in the washer. 3. Blow through system with heating and cooling coils and mixing dampers (Fig. 3). This is used where several different zones are served from one central system and the conditioning of the entering air for each zone is obtained by mixing varying quantities of air after passing through the heating and cooling coils. Fig. 1. Central System with Coils and Sprays CHAPTER 21- CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING Fig. 3. Blow through Systems with Coils and Mixing Dampers i 5i stt 1 f e afi. /!* Humidifying sprays moor P %\sMotor 1 IFen X 8 c < 'o y. Op 21 cc = oo s & 4! qj Supply duct zone-2 Fig. 4. Central System with Recirculating Conditioners 4. Central outside air conditioning system with zone recirculating conditioners (Fig. 4). This is used on installations having large zones requiring independent control to meet local requirements for office and apartment buildings, hotels, etc. 5. Central conditioning system using either washer or coils with booster reheating coils (Fig. 5). This is used for special zone control where there is great variation in heating requirements of different spaces, as may be caused by different exposures to wind and sun. 6. Residential system. In Fig. 6 is shown a combination of unit equipment used for residential air conditioning. The arrangement is similar to Fig. 1, but the coil, humidi fier, and.fan section may be purchased as a unit. The sketch shows a system.which permits the use of radiators or convectors in kitchens, baths, garages, and similar rooms. 378 Fig. 5. Central System with Booster Coils 379 HEATINC VENTILATING. AIR CONDITIONING GUIDE 1940 The addition of a cooling coil and compressor turns the system into a complete yearround conditioner. Reheating When air is dehumidified by cooling, the dry-bulb temperature leaving the dehumidifier is frequently lower than desired at the supply grille. In these cases, the dehumidified air must be reheated, and such reheating may be accomplished either by by-passing some air around the dehu midifier* (Fig. 2), or by using reheating coils. Study of Figs. 1 and 2 will make it obvious that without the by-pass, Fig. 6. Residential Conditioning System with Steam Boiler all of the air is first cooled and then subsequently reheated, but with the by-pass, only part of the air is cooled, heat required for. reheating being supplied by by-passed air. The by-pass thus reduces the cooling load and makes a separate reheating source unnecessary. DESIGN OF SYSTEM The factors which affect the design of an air conditioning system and the steps in the design are enumerated herewith. Item 1. Design conditions. a. Outside dry-bulb temperature in winter. b. Outside dry- and wet-bulb temperatures in summer. c. Inside dry- and wet-bulb temperatures (winter and summer). 'Patents exist covering the by-pass method. 380 CHAPTER 21. CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING Item 2. Design heating load. , a. Heat transfer through windows, walls, partitions, doors, floors, skylights, roofs. ' b. Heat loss resulting from infiltration. c. Heat required to warm ventilation air. d. Heat required to evaporate moisture for humidification. e. Heat loss through ducts and coil housings. /. Allowances for heat emitting sources. Item S. Design cooling load. a. Heat transfer through windows, walls, partitions, doors, floors, skylights, roofs, including solar radiation. b. The sensible and latent heat emission of occupants. c. Heat emission of electrical, chemical, gas, steam or hot water apparatus, or lights (divide into sensible and latent heat). d. The sensible and latent heat gains resulting from infiltration. e. Sensible and latent heat to be removed from ventilation air. /. Heat gain through ducts and coil housings. Item If. Design of the air conditioning system. a. Establish the air temperatures at supply grilles for winter and summer. b. Calculate the air quantities for winter and summer. 1. Adjust factors to get most satisfactory balance between winter and summer air quantities. . c. Select coils, washers, heat exchangers, etc., with capacities equal to heating and cooling loads established in Items 2 and S. d. Select air cleaning equipment. e. Select fans. /. Design duct system including supply and return grilles. g. Consider noise reduction problems. h. Design the control system. Calculate static pressure loss of the complete system. j. Select fan motors and drives and other auxiliary equipment. Design Conditions Outside design temperatures for principal cities are found in Chapter 7 for the heating season and in Chapter 8 for the cooling season. Recom mended inside design temperatures for various types of buildings and for the seasons are found in Chapters 3 and 7. ' Load Calculations for Heating Complete tabular information is given in Chapter 5 for determining the heat loss through windows, walls, partitions, doors, floors, skylights, ceilings and roofs. s The heating capacity required to warm infiltration air is determined by methods shown in Chapter 6. The minimum quantity of outside air brought in for ventilation is sometimes fixed by law; but when this is not the case, the A.S.H.V.E. Code8 should be used as a standard. Outside air in sufficient quantities provides the best method of controlling objectionable' odors, and the design should err on the safe side. Code requirements state that the assumed rate at which air is to be positively introduced into the enclosure per occupant, when the con tamination of air within the enclosures results entirely from respiratory process, shall not be less than 10 cfm per stated number of occupants *Loc. Cit. Note 1. 381 HEATING . VENTILATING AIR CONDITIONING GUIDE 1940 which is indicated as being the maximum number of people within the enclosure; when the sum of the remaining loads is a maximum. The Code further states that the assumed ventilation rates shall not be less than 15 cfm per stated number of occupants .in enclosures where smoking is customarily permitted, and that provision shall'be made for air removal from the enclosure either by .natural or mechanical means at not less than the assumed ventilation rate. For the purpose of the Code, air quality or purity are assumed to be met if means are provided for the positive intro duction of-outside air in the amounts previously mentioned and for removal of 95 per cent by count of all dust particles over 10 microns in diameter from all air delivered to the, enclosure. The heat required to warm ventilation air is determined in the same manner as for infiltration air. It should be kept in mind, however, that infiltration increases the amount of heat required to warm the conditioned space, while ventilation air adds to the load on the heating coil. The heat required to evaporate the necessary water required for winter humidification and superheat the resulting vapor in order to raise the moisture content of the outside air assumed to enter the enclosure by infiltration or positively introduced for ventilation should be calculated according to the information included in Chapter 1. Information is given in Chapter 40 for calculating heat transfer through ducts and housings. The heat emission of occupants, lights, and other sources is treated later in this chapter. This heat gain may be used as a credit against the heat loss calculations. In general, however, the design for heating disregards these gains as in most cases these values are not a continuous or uniform source of heat and the heating system must be adequate to maintain the required temperature at all times including nights, Sundays and holidays, when the space is not in normal use. ,, .. The sum of the several losses (Items 2a and 2b) will give the amount of heat to be supplied to the conditioned space. The above quantity plus ventilation and humidification load and heat loss in ducts represents load on conditioner. . Load Calculations for; Cooling - . The heat gain through the windows, partitions, doors, floors, sky lights, ceilings or roofs of the enclosure due to the air dry-bulb tempera^ ture difference assumed to exist between the air on the opposite sides of the construction may be determined from data given in Chapter 5. Charts and tables :are given in Chapter 8 for the determination of sun effect on walls, roofs, and windows. The heat gain from occupants may be calculated from data in Chapter 3, which give the metabolic rate for people engaged in various activities. In addition charts are included which give a separation of the sensible and latent heat losses from the body which should be itemized separately in all calculations. . The heat emission from various appliances should be calculated ac cording the to information and data given in Chapter 8, with, special consideration being given to the division of latent and sensible heat requirements of the apparatus. Complete details may also be found in 382 CHAPTER 21. CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING Chapter 8 for determining the heat gain resulting from electric lights and motors within the enclosure. . , . The heat gain from infiltration air'and ventilation air is determined by the method shown in Chapter 6. Separate sensible and latent heat. (See Chapter 40 for heat gain in ducts.) .. Air Distribution System for Heating The total heating load to be.supplied by the central system is de termined from the several components of the load listed under Item 2. The quantity, air motion, and temperature of the treated air and the method of introducing it to the. conditioned space should be designed so as to limit the variation in dry-bulb temperature to 3 F or less at a 5 ft level throughout that portion of the enclosure which is normally fre quented by persons. It is desirable to avoid air velocities exceeding 50 linear feet per minute in the occupied zone between the floor and the 5 ft level. When architectural or other construction requirements necessitate the location of a supply or return grille below the 5 ft level in an occupied space, special consideration should be given to the air velocities in that region to avoid uncomfortable drafts. .' It is desirable to use reasonably low temperature differences between the entering air and room conditions where possible. Air temperatures from 80 to 90 F will generally be satisfactory, although where the quantity of air to be circulated is kept at a minimum and where the arrangement of air inlets permits adequate mixing with the room air before reaching the breathing zone, higher temperatures from 100 to 120 F can be used. Having selected the desired temperature of the entering air, the quantity of air is determined as follows: _________ H________ Q ~ Wd X 0.24 (i* - A) where Q = volume of air to be introduced, cubic feet per minute. H = sensible heat loss of space to be conditioned, Btu per hour. - ' d = density of air, pounds per cubic foot. h = outlet temperature at the grille, degrees Fahrenheit. ' <i = design room temperature, degrees Fahrenheit. , ' If the air quantity calculated is excessive, it may be decreased by using a higher entering temperature. If the quantity is too small to provide adequate distribution and ventilation, it may be increased by using a lower entering temperature. Air motion has a cooling effect on the individual, and ordinarily the air quantity circulated should provide an overall air change in the conditioned space in not less than 5 min or more than .12 min. Best results are secured when the entering air temperature and method of distribution permit uniform mixture of air without excessive motion in the occupied zone. After air temperatures are established, the heat loss from ducts may be approximated (see Chapter 40). The resulting temperature drop can be calculated by solving';Equation 2. , ______ Hd______ . a 1 = 60 d X 0.24 X Q . (of ' 383 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 where A < = temperature drop, degrees Fahrenheit. ffd = heat loss in duct, Btu per hour. Unless the duct passes through an unheated portion of the building', heat loss from ducts can frequently be neglected. Final decision rests on careful analysis of local conditions. The duct distribution system is designed using velocities as recom mended in Chapter 30, and grille locations as discussed in Chapter 29. In most installations it is advisable in order to permit economical heating prior to occupancy to design the return duct system of sufficient area to convey 100 per cent of the air handled by the fan. Also in mild weather certain economies of operation may be affected by designing the outside air duct of sufficient area to convey approximately the total quantity of air handled by the fan and means should be provided for the escape of this air quantity. In every case, however, the outside air duct must be of sufficient area to pass minimum ventilation air. Air Distribution System for Cooling The total cooling and dehumidifying load to be supplied by the central system is determined from the several components of the design load listed under Item 8. The entering air temperature is determined by selecting the proper relationship between the quantity of air to be handled, the heat gain in the conditioned space, and the location of the air inlets. In cooling applications it is desirable that the difference between the temperature of air currents in the space frequented by occupants and the average temperature in such space, be not greater than 2 F for air veloc ities of 40 linear feet per minute and over and not greater than 3 F for velocities of less than 40 linear feet per minute. There is a fairly wide range of permissible entering air temperatures. With high velocity jets or diffusing nozzles, located at some distance from the occupied space, entering .air temperatures may be as much as 30 F below room temperature. Where the air is introduced through supply inlets fairly close to the occupied zone the entering air should be within 10 to 15 F of a desired room temperature. The problem of preventing drafts in summer air conditioning is important as air, cooler than room air, tends to fall without diffusing and proper design must consider the relationship between temperature and diffusion to secure satisfactory results. The relation between heat gain, air quantity, and air temperatures is given by Equation 1. For cooling, A and A are reversed. At this stage-in the design, the only known quantities are H and A- The maximum and minimum limits for Q are the same as given for heating, and A may be from 10 to 30 F below tu depending on room size and shape and type and location of supply grilles. Moisture added within the conditioned space does not increase the dry-bulb temperature in the space, and therefore only the total sensible heat gain to the space is used for H in Equation 1. Any reasonable value may be assigned to A and a trial calculation made. The value of Q obtained should lie within the proper limits; and if coils are to be used, the 384 CHAPTER 21. CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING air quantity should be investigated to determine the most economical coil size. To absorb the moisture load, the supply air must enter the space with a lower dew-point than that desired in the conditioned space. A method for determining this dew-point reduction follows: Total all the latent heat gains in the room and convert them to equivalent grains of moisture. Divide the total grains of moisture by the number of pounds of air delivered to the room which will give the difference in weight of moisture between the entering air and room air conditions. Subtract this amount from the grains of moisture corresponding to the dew-point temperature in the room and refer to psychrometric charts or tables to establish the required dew-point temperature of the entering air. The intersection of this new dew-point condition with the dry-bulb temperature line of the entering air at the supply inlet to the room will establish the entering wet-bulb temperature condition. When the supply duct passes through an unconditioned space, the dry-bulb temperature rise in the duct should be estimated (see Chapter 40). This temperature rise usually ranges from 1 to 3 deg and is deducted from A to establish dry-bulb temperature leaving conditioner. Ducts intended for low temperature air must frequently be insulated to prevent condensation on outer surfaces, even though heat saving is not large enough to justify the cost of covering. It is seldom that standard equipment will produce exactly the com bination of dry-bulb and dew-point temperatures indicated by preceding calculations, and it becomes necessary to revise assumptions regarding grille temperature, air quantity, refrigerant temperature, and air velocity through conditioner until the proper balance is obtained. When such alterations fail to produce desired results, reheating is indicated. Re heating methods have been previously mentioned in this chapter. The design of a duct distribution system for cooling is accomplished in the same manner as that previously described for heating installations. For cooling spaces prior to occupancy, it is also desirable to design the return air ducts of sufficient area to convey 100 per cent of the air handled by the fan and the same recommendations with regard to the outside air duct as referred to in the heating design would be applicable for summer air conditioning. CORRELATION OF SUMMER AND WINTER DESICN Frequently the quantity of air required for the central system in summer conditioning is considerably greater than the quantity required for winter conditioning. In practice, volume control should be provided using a speed regulator on the fan, or dampers, so that the air quantity may be changed for the cooling and heating cycles. Sometimes a recalcu lation using different entering air temperatures will permit using the same quantity of air all year round. There is no fixed rule or method for determining the most practical design for air quantity and the engineer should use discretion to a large extent in working out a balanced system. If the system is to be used for heating only, good results will be obtained with supply grilles located in the baseboard. For cooling systems, it is better to locate them in sidewalls above heads of occupants or in the ceiling. This same location will be satisfactory for year-round systems, "ffcially if the supply temperature in winter does not exceed 100 to 110 F. Air distribution is discussed in more detail in Chapter 29. 385 HEATING VENTILATING; AIR CONDITIONING GUIDE 1940 SELECTION OF EQUIPMENT The type of system to be used is controlled by the existing load con ditions, the degree of perfection expected frorn the system, and the designer's'knowledge of the operating characteristics of the various types of equipment. Information about equipment is available in other chapters and. in the Catalog Data Section.= It is considered good practice to provide for total recirculation in order to reduce operating costs during unoccupied periods. , And. it is also less expensive to use all outdoor air for cooling when the outdoor wet-bulb temperature is lower than that of the return air. ; The . process of evaporative cooling may, in some localities, provide interior conditions which are adequate for certain occupancies. Outdoor air is drawn through a spray of recirculated water which is not mechani cally cooled. The equilibrium temperature for heat exchange is the wetbulb temperature of the entering air. In actual washers (see Chapter 26), the dry-bulb temperature does not fall to the wet-bulb temperature but only approaches it. To get much cooling effect, it is necessary to have a large differential between dry- and wet-bulb temperatures of outdoor air. Hence, this method is only feasible in those sections where the air temperature is high and the relative humidity is low. Also because the wet-bulb temperature of the air does not change in passing through the spray, this method is not recommended for cooling loads, with a high proportion of latent heat. In making the selection between spray and surface; dehumidifiers, certain characteristics of each should be considered. A spray dehumidi fier, (i.e., dehumidifying air washer) will deliver practically saturated air, the temperature of which is determined by the temperature of the air washer water. The control in.this case is the control of the water tempera ture and cooling effect can be accomplished by an external water cooler, a natural cold water supply, or , coils installed directly in the washer. The washer system is used in the winter time for humidifying in the same way; that is, by controlling the water temperature, water can be evapo rated into the air. This may require preheating the air before entering the washer, or the use of an external water heater, or steam coils directly in the washer. Air washers also have the ability to eliminate certain kinds of dirt and dissolved gases and some odors. ... In common practice, the air leaving a cooling coil is not saturated. But as most comfort-conditioning systems require some differential between delivery dry-bulb and dew-point temperatures, it frequently happens that by careful selection the right combination can be produced by the coil, eliminating the need of reheating. Strictly speaking, the desired performances will be obtained only at full load, there being some fluctuation in room relative humidity at light loads. Such variation is usually within the allowable limits for comfort work. It is essential that a good filter be placed ahead of a cooling coil, otherwise sufficient dust will soon adhere to the wet coil to completely block the air passage. The relation between sensible and latent heat is of great importance in the performance of cooling coils. Unfortunately, no uniformity exists at present in stating this ratio; and the several possible methods are given in Table 1 together with typical values for various occupancies. It must be 386 CHAPTER 21. CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING remembered that these values are typical and should in no case be arbitrarily assumed to be correct for any given problem. The procedure for selecting both heating and cooling coils is given in Chapter 25, and coil performance tables may be.found in the manufac turers' catalogs. Some manufacturers have standardized on 4-tow cooling coils and offer them at lower prices per square foot of surface than for other depths. By changing face velocity within permissible limits, 4-row coils can be adapted to many cooling jobs. '" The characteristics of washers are discussed in Chapter 26; Dimensions will be found in manufacturers' catalogs. Table 1. Room Heat Load Ratios for Typical Summer Comfort Conditioning Room Heat Load Ratios* Sensible Heat Total Heat ' Typical Classes or'Room Sebticb ob Load No. Occupants or Sources .of Vapor Private Office or Residence Restaurant . or Crowded ' Office 1.00 0.90 0.80 Auditorium at Capacity or Crowded Restaurant. ' Ballroom at . Capacity 0-70 0.60 Total Heat Sensible Heat 1.00 1.11 1.25. 143 1.67 Latent Heat Total Heat 0 0.10 0.20 0.30 0.40 Total Heat Latent Heat 10.00 5.00 3.33 2.50 Sensible Heat Latent Heat -- 9.00 4.00 2.33. 1.50 Latent Heat Sensible Heat 0 0.11 0.25 0.43 0.67 Tv"lil.e overall hL-atlo:id ratio for the dehumidifier will be different from the heat load ratio for the room. c difference will depend on the quantity and condition of the outside air used, upon the magnitude of the duct losses, and upon whether or not reheat or by-pas3 are used. If coils are used, humidification may be accomplished in winter by use of a separate humidifier. On small installations, the simplest method is to use a warm water spray through atomizing nozzles, using a pressure of 15 to 25 lb and sufficient nozzles to atomize about twice the amount of water needed for humidifying. The grains of moisture to be added to the incoming air at outside design temperature to bring it up to the required room dew-point are calculated. This is converted to total pounds of water per hour for the system and sprays designed for twice this amount. Cold water will not vaporize as completely as warm water, and water temperatures from 120 to. 150 F are commonly used. Another method is to install a water tank in the air stream with a steam coil subjnerged in the tank, the humidification being accomplished by the steam boiling the water into vapor, which in turn will be absorbed by the passing air. In both of these systems there is a tendency to deposit lime and other impurities on any surface the water touches, and this scale should be 387 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 cleaned regularly before it becomes excessive. Water spray should not touch the steam heating coils as they will quickly become coated with scale. The preferred practice is to install sprays between coils and eliminator plates. Filters, Fans and Motors For a discussion of air cleaning devices and for the selection of all types of air filtering equipment refer to Chapter 27. The selection of fans, motors and their control may be based on data available in Chapters 28 and 39. Sound Control Problems of sound control should be jointly considered by the acous tical and air conditioning engineer for satisfactory results. Many instal lations require noise levels which are relatively low and for that reason equipment must be selected having a very low noise rating. In central systems consideration should also be given to the lining of ducts for the reduction of noise levels within an enclosure. Often reduced speeds of equipment and low air velocities are helpful in eliminating undesirable noise conditions. Information is given in Chapter 31 with regard to acceptable noise levels for various types of rooms and methods are out lined for computing length of duct lining materials. Automatic Control The control of an air conditioning system is very important. A simple comfort cooling or heating installation requires a minimum of control, whereas a more complex installation justifies a more complete control. In this connection, there are many patents allowed and pending on air conditioning equipment including control, and the designer should con sider these factors in selecting equipment. Refer to Chapter 38. Static Pressure The static pressure against which the fan must operate is the sum of all pressure losses through all parts of the complete system. Resistances of equipment such as coils, washers, filters, and grilles is obtained from data given in the manufacturers' catalogs. Pressure drop in the duct is calcu lated as shown in Chapter 30. 1 . SPECIAL CONSIDERATIONS In designing a central system for air conditioning there are a number of special considerations not referred to previously which must be considered. Certain features of building constructions are important. The building must be suitable in construction so that the desired conditions can be maintained economically. - For instance, excessive sun load on roofs or glass windows may not only cause excessive heat gain to be absorbed by refrigeration, but direct sun radiation heating converts a surface into a panel heater. This radiant heat is not absorbed until it strikes another mass such as a building wall, or a person. It is therefore possible to have comfortable air conditions surrounding a person, and yet have him uncomfortably warm from radiant heat from a hot wall, window, or ceiling near him. As another example, it is much better to provide hoods over steam tables, coffee urns, etc., than to try to remove this heat by mechanical refrigeration. ' 388 CHAPTER 21. CENTRAL SYSTEMS FOR COMFORT AIR CONDITIONING Another problem is presented with winter conditioning for maintaining satisfactory relative humidity. If 30 to 40 per cent is desired at all times, no matter how cold it is outside, excessive condensation may collect on single glass windows, or on hardware which connects to the outside such as latches and hinges. Condensation on windows can sometimes be pre vented by applying a small amount of local heat under the window. In other cases double glass or storm window construction is used. Refer to Chapters 5 and 7 for condensation temperatures. In many cases, different zones of a building will require entirely different treatment. In some buildings where offices are exposed on all four sides to sun and wind effect, cooling is required on the sunny side and heating is required on the shady side simultaneously, in spring and fall seasons. The central system must be carefully zoned to apply cooling or heating as they may be needed for each zone, independent of other zones. In many existing buildings, the central system will be added to a radiation system of heating. The designer should take full avantage of this radiation for heating the outside walls and windows. At the same time, it must be controlled to prevent overheating the whole system. A few uncontrolled radiators will often change the heat balance and cause excessive overheating of the whole zone, without occupants near the radiators realizing the source of the trouble. All radiation used locally in connection with the control system should be equipped with automatic control to prevent overheating. The apparatus should be placed for . minimum piping and duct work but it must be accessible for maintenance, repair, and cleaning. The air conditioning unit should be designed to provide access for cleaning coils, drip pans, eliminators and for very easy maintenance on filters. This equipment will be in operation for many years, probably for the life of the building, and a little thought spent in the plan will simplify maintenance and assure successful results. Example 1. With the assumed values as indicated perform the essential calculations to determine the design loads for heating and cooling and the necessary factors for de signing the distribution system. Solution: Design Conditions from Item 1. Outside air dry-bulb, winter................ ...................................................... 0 F Outside air dry-bulb, summer........................ ............ ...............................95 F Outside air wet-bulb, summer.________________ _____ ___ ___________ 75 F . Inside air dry-bulb, winter............... ...........................................................72 F Inside air wet-bulb, winter...... ................................................................. :.56 F Inside air relative humidity, winter............. ........................................... 35 per cent Inside air dry-bulb, summer.......... .......... ^.............................................. ,.80 F Inside ajr wet-bulb, summer......... ........ ............................. ...................... 66.7 F Inside air relative humidity, summer.... ...... ............................................50 per cent 200 people---4 kw light load. > Design Load for Heating from Item S. Sensible heat loss through walls, etc200,000 Btu per hour Outside air--2000 cfm X 0.075 X 60 X 0.24 X(72 - 0) = 155,500 Btu per hour Humidification- .200p_X0-QW XJO XjjO-5) X1040 = 46>900 Btu per hour . 7\aJ0 . Heat loss through ducts.______________ ____________ ___ _____ 33,200 Btu per hour Heat gain from lights, etc......... ........ .......................... Disregard Total heating load......................................................... ;..................435,600 Btu per hour 389 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Design Load for Cooling and Dehumidifying from Item 3. ' . . Sensible. Heat gain through walls, etc...................... .----128,160 Heat gain from occupants (200)........................ -- 44,000 Heat emission from appliances.....................................2,000 Heat gain from lights (4 kw)--............................. 13,840 Heat gain from solar radiation...,__ __________ 12,000 Latent 36,000 .- Totals.:....................................... ...... --............-200,000 Outside air: 2000 X 0 075 X 60 X 0.24 X (95 - 80) = 32,350 2000 X 0.075 X 60 X (96 - 77.2) X 1060 7000 .. Heat gain through ducts____________________ -- 22,200 36,000 Btu per hour 25.600 : Totals.. Total Cooling Load Tons Cooling Effect Ratio S.H. to T.H. ..254,550 = 316,150 Btu per hour = 26.4 . 200,000 = 0.85 (Room) 236,000 61.600 Btu per hour 254,550 =, .805 (Con- 316,150 . ditioner) Design Distribution System for Heating a. Total heat loss in space ' Assume grille temperature. : 200,000 . Q 60 X 0.075 X 0.24 X (90 - 72) - 200,000 Btu per hour 90 F 10,300 cfm b. Total heat loss in ducts between unit and grilles 33.200 Btu per hour a , 33,200 60 X 0.075 X 0.24 X 10,300 c. 90 F plus 3 F 3F . 93: F temperature leaving coil Design Distribution System for Cooling a. Total sensible heat gain in space 200,000 Btu per hour Assume grille^temperature 200,000 _ = 10,300 cfm = 60 X 0.075 X 0.24 X (80 - 62) .. 62 F- r 770 lb per minute' b. Latent heat gain in space 36,000 Btu per hour 600 X 7000 1060 600 Btu ,per minute 3970 gr per minute 3970 -5- 770 = 5.2 gr per pound air supplied Room condition = 80 F DB, 50% RH, 60 F DP Gain in conditioned space 77.2 gr per pound 5.2 gr per pound Specific humidity leaving conditioner . i 72.0. gr per pound Grille temperature = 62 F DB and 58 F DP c. Duct gain A t =- 22,200 60 X 0.075 X 0.24 X 10,300 . ' Leaving coil = 60 F DB, 58.7 F WB, 58 F DP 22.200 Btu per hour 2 F temperature rise These calculations are based on maximum load conditions as set forth in the design. For intermediate loads the calculations may show entirely different relationship. For example, the entering air temperature will approach the space temperature as the sensible heat gain or loss decreases, due to outside temperature change, entrance or exit of people, use of artificial lighting, direction and intensity of sun's rays. The entering dew-point will remain much more uniform as it is affected by changes in room moisture 390 CHAPTER 21. CENTRAL SYSTEMS EOR COMFORT AIR CONDITIONING in oiily and this does not fluctuate greatly. If intermediate load conditions are im portant the calculations should be repeated for those loads. Example 2. . Determine the cooling load for a theater if the following design con ditions are assumed. A dehumidifying air washer is to be used with and without the by-pass. : Outside air dry-bulb.......................... ,-- ............ ........................ 94 F Outside air wet-bulb.------ ---------------- -------------------------- ----- -------- 75 F Inside air dry-bulb--------------------------------------------------------------- - 80 F Inside air wet-bulb............................ ..............................--............... 67 F Minimum outdoor air........ ............ .................................................... 6300 cfm People. --............ -..... ................................. --:-- ......... ............. ' 600 Lights................. ............ ....................... ...... .......... ........... ................... 4 kw Transmission gain--..................... .......... ......... ........................ ......... 110,000 Btu per hour Solution. Without By-Pass. where ' <i = dry-bulb temperature, room or return air, degrees Fahrenheit, ft = dry-bulb temperature at supply grille, degrees Fahrenheit, ft = saturation temperature leaving washer, degrees Fahrenheit, f" = dew-point in room, degrees Fahrenheit, -.. f" = dew-point at supply grille, degrees Fahrenheit. hi = enthalpy of room air, Btu per pound. he = enthalpy of outside air, Btu per pound. hi = enthalpy of air leaving washer, Btu per pound. Design Load for Cooling from Item S. Sensible Transmission........... ............................... 110,000 People (600)........ 132,000 Lights (4 kw).......................................... 13,800 , ' Latent 720,000 Totals____________ ____ _______ .255,800 Btu per hour 720,000- gr. per hour Determine Air Quantity Sensible heat gain in space Assume grille temperature ,, _ 255,800 y 60 X 0.24 (80 - 68) : = 255,800 Btu per hour = 68 F = 1,480 lb per min = 19,700 cfm ' Minimum outdoor air .= . 470 lb per min = 6,300cfm Return air = 1,010 lb per min Moisture gain in space = 720,000 gr per hour 12,000 4- 1,480 = 8.11 gr per pound air supplied Room conditions = 80 F DB, 67 F WB, 60 F DP Gain in conditioned space = 13,400cfm = 12,000 gr per min = 77.21 gr per lb =.. . 8.11 gr per lb Specific humidity leaving conditioner Grille conditions = 68 F DB and 57 F DP 391 = 69.1 gr per lb HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Determine Cooling Load on Air Washer Heat removed, outside air = 470 {ho -- hj) = 470 (38.46 24.4) = 6600 Btu per min Heat removed, return air = 1010 {hi -- hi) = 1010 (31.51 -- 24.4) 7180 Btu per min Total Refrigerating effect = 13,780 -e 200 -- 68.9 tons. 13,780 Btu per min Determine Reheating Required H = Wcp {to - h) = 1480 X 0.24 (68 -- 57) = 3910 Btu per minute = 234,600 Btu per hour. Solution. With By-Pass where x = air to be by-passed, pound per pound total air. y = air passed through washer, pound per pound total air. (< = dry-bulb temperature after mixing with by-passed air, degrees Fahrenheit. <4 = to if no temperature rise in duct is assumed. Determine Amount of By-Pass Air and Saturation Temperature Leaving Washer* hx + hy = /j t\x + hy = t 80* + hy = 68 60* + hy = 57 20* = 11 * = 0.55 y = 1 - 0.55 = 0.45 80 X 0.55 + 0.45/, = 68 h = 53.3 F Determining Cooling Load on Washer Air through washer = 0.45 X 1480 Outside air ' _ = 665 lb per min = 470 lb per min Return air through washer . = 196 lb per min Heat removed, outside air = 470 {ho -- hi) = 470 (38.46 -- 22.13) = ._ 7680 Btu per mm Heat removed, return air = 195 {hi -- hi) = 195 (31.51 -- 22.13) = 1830 Btu per min T0ta[ 9510 Btu per min Refrigerating effect 9510 -f- 200 47.55 tons Reheating--None. - Note: The Revised Biilkeley Psychrometric Chart and Table 6, Chapter 1 were used in the solution of these problems. . 4For derivation of these simultaneous equations see page 190 of The Guide 1937. 392 Chapter 22 UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS Unit Heaters, Ratings, Unit Ventilators, Applications, Window Ventilators, Unit Humidifiers, Types of Units IN other chapters, descriptions are given of heating, cooling, ventilating, humidifying, and dehumidifying systems. The success of such systems has led to the production of factory-assembled equipment employing a majority of the principles of these complete systems. As a result, present day practice involves the use of unitary equipment in the majority of installations where capacity and application demands are within the limits of such units. Thus unit heaters, unit ventilators, and unit humidi fiers described in this chapter, and cooling units, unit air conditioners, and attic fans described in Chapter 23 have come to occupy a place of their own in the industry. Unitary Equipment Unitary equipment was first applied in units of small capacity but increased experience in this field has led to an ever widening range of capacities and applications. In general a unit may be defined as a factory- made encased assembly of the functional elements indicated by its name, such as unit heater, unit ventilator, etc. These units are shipped sub stantially complete or built and shipped in sections so that the only field work necessary is the assembling together of the sections, without resorting to any field fabrication. . A unit may be complete in itself, employing its own direct means of air distribution and source of heating, in which case it thus represents a complete self-contained unit. Or it may be coupled with separate means of air distribution such as duct work and outlets, in which case it will still be considered as a unit system, as contrasted with the generally accepted term of a field fabricated central station system. The manu facturer of the unit is responsible for the output and performance of the unit under rated conditions, whereas the contractor installing the com plete unitary system is normally held responsible for the performance of the complete system. . Unit equipment justifies its existence due to the following features: Lower cost per unit capacity. Standardized design and volume production makes possible low cost factory assembly thereby eliminating individual design and handling of every part for each installation. . 393 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 2. Flexibility and mobility of equipment. Unitary equipment can be readily located in existing buildings without the necessity of running large ducts through floors and many partitions. Such equipment can be shifted to meet changing requirements. Tenants may obtain the advantages of conditioning when the entire building is not equipped with a conditioning system. In industrial process work, the flexibility of unitary equipment is also advantageous. 3. Lower installation costs. The fact that the equipment arrives on the job in an assembled condition, coupled with the lesser problems of duct work and connecting piping, materially reduces installation costs. 4. Small capacities. The small capacities available in unitary equipment have brought the advantages of controlled air conditions to a number of small offices, stores, shops, and individual rooms where specially designed and built central system equipment would have been uneconomic. Definitions With the growth of the unit equipment industry, it becomes increas ingly evident that there is no sharp line of demarcation, on the basis of capacity, between a unit and a central plant system. The definitions contained in a code, Standard Method of Rating and Testing Air Con ditioning Equipment1, have helped to clarify and identify the various types of equipment since the definitions are given on a purely functional basis. The following definitions are. taken from the code: 1. A Heating Unit is a specific air treating combination consisting of means for air circulation and heating within prescribed temperature limits. 2. A Heating Air Conditioning Unit is a specific air treating combination consisting of means for ventilation, air circulation, air cleaning and heat transfer with control means for heating and maintaining humidity within prescribed limits. 3. A Humidifying Unit adds water vapor to and circulates air in a space to be hu midified. . 4. A Free Delivery Type Unit takes in air and discharges it directly to the space to be treated without external elements which impose air resistance. 5. A Pressure Type Unit is for use with one or more external elements which impose air resistance. UNIT HEATERS A unit heater consists of the combination of a'heating element and fan or blower having a common enclosure and placed within or adjacent to the space to be heated. Generally no ducts are attached to inlets or outlets, although it is common practice with many unit heater appli cations to equip the heaters with directional outlets or adjustable louvers. While unit heaters are designed primarily to handle all recirculated air, they may be installed to handle either partial or total outdoor air. Features A wide variety of structural designs is available. All employ some form of heat transfer surface, supplied with steam, hot water, gai or electric heat. Air is always forced over or drawn through the heat transfer surface by a.fan of either the propeller or centrifugal type. Heat ing surfaces may be in the form of non-ferrous or steel pipe coils, nonferrous or steel pipe with extended surfaces, cast-iron, or pressed or built-up sections of the cartridge or automotive type. 'Prepared by a Joint Committee of the American Society of Refrigerating Engineers, American Society of Heating and Ventilating Engineers, Refrigerating Machinery Association, National Electrical Manu facturers' Association and Air Conditioning Manufacturers' Association, ' 394 CHAPTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS . Compared with the older method of heating by radiation, properly designed and applied unit heaters should: 1. Circulate air in the building at a rapid rate but without objectionable draft. 2. Reduce the temperature differential between the floor and ceiling. 3. Direct the heated air so that uniform temperature distribution will be obtained throughout the heated space. 4. Prevent or remove the cold stratum of air commonly found at the floor level. 5. Reduce the number of heating elements required and thereby decrease the cost and extent of the piping necessary. 6. Maintain a closer control of room temperature either manually or by means of simple thermostats. 7. Produce an economy in heating costs resulting from the sum total of the above advantages. 8. Provide a means of saving floor area orYoom space due to the compactness of the equipment and flexibility of application. " Fig. 1. Floor Mounted UNtr Heater, Housed Type Fan . Types of Units : There are two major tyjbes of unit heaters, centrifugal housed fan type and propeller fan type. - The housed fan high velocity (1500 to 2500 fpm) discharge units with outlets adjustable to deliver air in several directions, are able to project their heating effect over distances of from 30 ft to as much as 200 ft from the unit. This makes possible the location of these units at considerable distances from each other, thus reducing greatly the piping and loss of floor space due to the heating equipment. Figs. 1 and 3 illustrate the housed fan type of unit. . Propeller fan type of unit heaters are used extensively to heat the small commercial establishment, although this type of unit is also available in very large sizes. Fig. 2 illustrates a propeller fan type of heater. A code2 governing the number of sizes of propeller fan type units as well as . Standards lor Propeller Type Unit Heaters prepared and adopted by the Industrial Unit Heater A <so- ruuton, June, 1938. . 395 HEATING VENTILATING AIR CONDITIONING GUIDE '940 Standardization of fan motor types and the method of specifying outlet . velocities has been adopted. RaStintagns dard practice is to rate unit heaters in Btu per hour at a given temperature of air entering the heater and at a given steam pressure maintained in the coil. Steam at 2 lb pressure and air entering at 60 F are used as the standard basis of rating3.. The capacity of a heater increases as the steam pressure increases, and decreases as the entering air temperature increases. The heating capacity for any condition of steam pressure and entering air temperature may be calculated approxi mately from any given rating by the use of factors in Tables 1 and 2. Table 1 is used for the blow-through type and Table 2 for the drawthrough type of unit. The formulae given'under unit ventilators for calculating capacities also apply to unit heaters. The temperature to be maintained4 in the room, for recirculating heaters with intakes at the floor level, should be considered as the tem perature of the air entering the heater. Where outside air is introduced, the temperature of the mixture must be calculated and used as the entering air temperature to the heater. Unit heaters taking in recircu lated air at the floor level should maintain temperature differentials of less than 0.5 deg per foot of elevation when the maximum capacity of the heaters is required. This temperature difference per foot of elevation is less than the corresponding variations for spaces heated by direct radi atiTonh.e temperature variation from floor to c. eiling with suspended unit heaters taking air at some distance above the floor, may reach as much as 1 deg per foot of elevation during the periods when the maximum capacity of the heaters is required. Thus this allowance should be made in calcu- *A,S.H.V.. Standard Code for Testing and Rating Steam Unit Heaters (A.S.H.V.E. Transactions Vbyo^Ol A3-.6SL. ..H1L9.a3V0r.sE, op.n.R.1eD6s5.e)Wa. r.cNheRlseopno,ratnNd oO. .9C58.--CTroemmepre(rAat.uSr.eHG.Vr.aEd.ieTnrtaOnbssaecrtviaotniosn.sVionl.a3L9a.rg1e93H3.eapt.e2d4S3p).ace. A.S.H.V.E. Research ReportNo. 1011--Teats of Three Heating Systems in an Industrial Type of Build ing. by G- L. Larson. D. W. Nelson, and John James (A.S.H.V.E. Transactions. Vol. 41. 1935. p. 185). 396 CHAPTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS lating the capacity of suspended heaters. High velocity discharge units (blower type illustrated in Fig. 3) will maintain slightly lower temperature differences than will low velocity units (propeller fan type illustrated in Fig- 2). Unit heaters are customarily rated as free delivery type units. If outside air intakes, filters, or ducts on the discharge side are used with the heater, proper consideration should be given to the reduction in air and heating capacity that will result because of this added resistance. The percentage of this reduction in capacity will depend upon the characteristics of the heater and on the type, design and speed of the fans so that no specific percentage reduction can be assigned for all heaters at a given added resistance. In general, however, disc or propeller fan type units will experience a larger reduction in capacity than housed centrifugal fan units for a given added resistance and a given heater will have a larger reduction in capacity as the fan speed is lowered. When confronted with this problem the ratings under the conditions expected should be secured from the manufacturer. Boiler Capacity The capacity of the boiler should be based on the rated capacity of the heaters at the lowest entering air temperature that will occur, plus an allowance for line losses. Ordinarily for recirculating heaters the lowest entering temperature will occur at the beginning of the heating period and is usually taken as 40 F, while for ventilators taking air from outdoors the lowest entering temperature will be the extreme outdoor temperature expected in the district. No greater allowance in boiler capacity beyond the calculated heat demand need be added in order to supply unit heaters than for any other type of system. It is unwise to install a single unit heater as the sole load on any boiler, particularly if the unit heater motor is started and stopped by thermo static control. The wide and sudden fluctuations of load that occur under such conditions would require closer attendance to the boiler than is usually possible in a small installation. Where oil or gas is used to fire the boiler, it is possible by means of a pressurestat to control the boiler, in response to this rapid fluctuation. In most cases, however, and particularly where the boiler is coal-fired, it is advisable to use two or more smaller heating uqits instead of one large unit. Steam pressures below 5 lb can be used with safety for recirculating unit heaters when their coils are designed for the purpose and when proper provision is made for returning the condensate. If ventilators are to take in air that may be at a temperature below freezing, however, a steam pressure of not less than 5 lb should be maintained on the convector or a corresponding differential in pressure between the supply and returns be maintained by means of a vacuum. Piping Connections Piping connections for unit heaters are similar to those for other types of fan blast heaters. The piping around the unit heaters must strictly conform to the system requirements while at the same time permitting the heaters themselves to function as intended. The basic piping princi ples for steam systems are discussed in Chapter 16. . 397 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 398 CHAPTER 22. UNIT. HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS --I O ^^ g2 59 8 - Oco 932 OO 00 00 CN 3. C-4 CN a, ce sS s 399 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Rapid condensation of steam, especially during heating-up periods, is characteristic of this type of equipment. The piping must be planned to accommodate this rapid condensation, must keep the surfaces free of water; while on the supply side the piping must be ample to carry a full supply of steam to the surfaces to take the place of that condensed. Adequate size of pipe is thus essential to all heating surfaces over which there is a forced flow of air. Especially is this true where the fan is operated under start-and-stop control and where the air handled may be made up either wholly or partly of cold air from outside the building. In such installations the condensation rate may vary rapidly and the necessity for ample pipe capacity is especially acute. A method of connecting a unit heater to a one-pipe gravity system is illustrated in Fig. 4. In those cases where the unit heater is to be con- CHAPTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS , Since unit heaters are often constructed with sufficient strength to resist high pressures, use of high pressure steam in them is a common practice. In Fig. 7 the condensate and air reach the return overhead through traps, and check valves are located in the return piping. For two-pipe closed gravity return systems, the return from each unit should be fitted with a heavy duty or blast trap, and an automatic air valve should be connected into the return header of each unit. Pressure drop must be compensated for by elevation of the heater above the water line of the boiler or of the receiver. In pump and receiver systems the air may be eliminated by individual air valves on the heaters, or it may be carried into the returns the same as for vacuum systems and the entire return system be free-vented to the atmosphere, provided all units, drip points, and radiation are properly trapped to prevent steam entering the returns. FigO.n4e. -pUipneitGrHaevaitteyrScteoanmneScytsitoenm . Gravity..S.__y__s__t__e_m____w___i_t__h___Wet, and Dry Returns nected to a dry return instead of a wet return it is necessary to provide a water pocket or loop about 5 ft in depth to prevent steam passing into the return and thus into other equipment. A method of connection is shown in Fig. 5, where there is a wet return and a dry return. In this case the condensate from'the heater and the drip from the supply main drop to the wet return by gravity, while the air passes upward through the traps to the dry return and is vented from the system at any suitable location. A sketch of an arrangement where there is a dry return line through which both air and condensate pass to be handled by some suitable means, such as a condensate pump and receiver is given in Fig. 6. The return line is not subjected to vacuum, and consequently all arrangements must facilitate gravity flow of the condensate toward the receiver. Trap's must pass air and condensate rapidly to keep the return piping only partially full of water. 400 Vacuum _o__r___V_ a_p__o__r____S__y_ stem Dischargrinugk Condensation into Dry Return t. riHGe. atermteothHoigdhoPfrCeossnunreectRinegtuUrnnit On vacuum or open vented systems the return from each unit should be fitted with a large capacity trap to discharge the water of condensation and with a thermostatic air valve for eliminating the air, or with a heavyduty trap for handling both the condensation and the air, provided the air finally can be eliminated at some other point in the return system. For high pressure systems the same kind of traps may be used as with vacuum systems, except that they must be constructed for the pressure used. If the air is to be eliminated at the return header of the unit, a high pressure air valve can be used; otherwise the air may be passed with the condensate through the high-pressure return trap, with some danger of return pipe corrosion and the problem of its elimination at some other point in the system. Application Unit heaters are used principally for commercial and industrial appli cations such as display rooms, garages, factories, factory offices and to 401 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 some extent for office applications where appearance is not a major factor. Unit heaters may be adapted to a number of industrial processes, such as drying and curing, with which the use of heated air in rapid circulation with uniform distribution is of particular advantage. They may be used for moisture absorption, such as fog removal in dye houses, or for the prevention of condensation on ceilings or other cold surfaces of buildings in which process moisture is given off. When such conditions are severe, it is necessary that the heaters draw air from outside in enough volume to provide a rapid air change and that they operate in conjunction with ventilators or fans for exhausting the moisture-laden air. (See discussion of condensation in Chapter 5.) There are three major factors to consider in the application of unit heaters, as follows: 1. location of Unit. ' 2. Air Distribution. 3. Heating Medium. . Heaters may be distributed through the central portions of a room discharging toward exposed surfaces, or may be spaced around the walls, discharging along the walls and inward as well, especially when there are considerable roof losses. Suspended type units are located in an elevated position withdrawing air from this higher level and discharging the heated air down into the working zone. This type of installation is illustrated in Figs. 2 and 3. Suspended type of units provide excellent temperature distribution. In closely occupied spaces where direct air drafts into the working zone are not permitted, the floor mounted unit will give more uniform tem perature distribution. These units draw the cold air from the floqr and discharge the heated air above the working zone. In general, it is better to direct the discharge from the unit heaters in such fashion that rotational circulation of the entire room content is set up by the system rather than to have the heaters discharge at random and in counter-directions. Various types and makes of unit heaters are illustrated in the Catalog Data Section of this edition. Usually hot blasts of air in working zones are objectionable, so heaters mounted on the floor should have their discharge outlets above the head line and suspended heaters should be placed in such manner and turned in such direction that the heated air stream will not be objectionable.in the working zone. In the interest of economy, however, the elevation of the heater outlet and the direction of discharge should be so arranged that the heated air shall be brought as close to the head line as possible, yet not into the working zone. In general, the higher the elevation of the unit, the greater the volume and velocity required to bring the warm air down to the working zone, and consequently, the lower the required temperature of the air leaving the unit. . ' Low or high pressure steam as well as hot water are generally used in unit heaters. Direct fired units are also available. Superheated steam can be satisfactorily used in unit heaters provided the capacity is based on saturated steam temperature and not on the total temperature. If 402 CHAPTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS unusually high superheat is used, trouble may be experienced from the excessive expansion and contraction of the heating elements. Electric, Direct-Fired, and Turbine-Driven Units The foregoing discussion relates generally to units in which steam or hot water is used as the heating medium. Electric unit heaters are applied where electric power is abundant and cheap and where other forms of fuel are scarce and expensive. The low first cost, easy control, and inexpensive installation of this type of heating have also accounted for many other installations in which electricity has conveniently provided heat for short periods of time. (See Chapter 41.) A recent development in gas burning equipment is the direct-fired industrial unit heater. These heaters are of the warm-air type and are equipped with fans which cause the air to pass over the heating surfaces at a fairly high velocity and then direct the warm air into the space to be heated. As is the case with the steam-fed unit heaters, the gas-fired appliances may be used for heating stores, shops, and warehouses. They usually are suspended in the space to be heated and in most instances leave the entire floor and wall area free for commercial use. Partial or complete automatic control also may be secured on appliances of this type. This type of heater is often used for temporary heat during building construction or where the installation of a steam or hot water plant is for some reason not justified. For permanent installations, it is usually advisable to provide an exhaust duct from the gas-fired unit heaters to remove products of combustion from the occupied space. While this is not necessary in large open industrial plants, in smaller closed rooms, it becomes essential. Where high pressure steam is available it is sometimes used to drive a steam turbine direct-connected to the unit heater. The exhaust from this turbine, reduced in pressure, is then passed into the heating coil where it is condensed and returned to the boiler. UNIT VENTILATORS5 Unit ventilators are similar in principle to unit heaters since ventilators incorporate ah encased heating surface through which outside air is forced by means of a blower or fan and may or may not have provision for' recirculation of air. While unit heaters are largely used for commercial and industrial applications, unit ventilators are intended primarily for schools, offices, and semi-commercial establishments. A typical unit ventilator is illustrated in Fig. 8. Specifications Unit ventilators usually consist of a semi-decorative cabinet containing the following necessary or optional parts: ' l. Outside air inlet. .: . 2. Inlet damper for closing the opening to the outside air inlet when the unit is not in use. / ? Chapt(537.Ventilator is 8011161111163 termed a unit ventilator. For information on roof ventilators,-see 403 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 3. Adhesive or dry type filters for cleaning the air (optional). 4. A heating element usually of special design and intended for low pressure steam. 5. Motor and fan assembly. 6. Mixing chamber where warm and cold air streams are brought together. 7. Outdoor air inlet and recirculating air mixing damper (optional). 8. Discharge grille or diffuser. 9. Temperature control arrangement. Functions and Features The primary functions and features of a unit ventilator are: 1. To supply a given quantity of outdoor air for ventilation or to mix indoor and outdoor air. (See A.S.H.V.E. Ventilation Standards, Chapter 46.) 2. To warm the air to approximately the room temperature if the unit is intended for ventilation only, or to a higher temperature if it is intended to take care of all or a part of the heat transmission losses from the room. Fig. 8. Typical Unit Ventilator Showing One of Many Arrangements of Dampers and Heating Coils 3. To control the temperature of the air delivered so as to prevent both cold drafts and4.oTveorhdeealitvinegr.air(Steoe tCheharpotoemr 3i8n.)such a manner tha, t proper distribution is. obtained without drafts. 5. To recirculate room air for the purpose of heating or promoting comfort when venti lation is unnecessary. (Ordinances should be consulted.) . 6. To perform all its functions without objectionable noise. ' 7. To clean the air properly. In general the features of this type of unit are quite similar to those given for unit heaters. Ratings . ( Unit ventilators are customarily furnished with two ratings, one established by anemometer readings and the other by condensation. The latter is for standard air. For the former, capacities vary from 750 to 10,000 cfm. Each size may be equipped with radiators for various rates 404 CHAPTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS Table 3. Typical Capacities of Unit Ventilators for an Entering Air Temperature of Zero Cubic Fhht of Am Peh Minute Anemometer Rating Condensate Hating Total Capacity in Square Feet, Equiv alent Direct Radiation Capacity Available fob Heat- ino TUB Rook, Sooabb Febt Equivalent Direct Radiation Temperature (Deo Fahb) 750 1000 1260 1560 500 750 1000 1250 214 320 427 534 ' 56 $4 112 141 95 95 95 95 of condensation, to give different final temperatures for a given air capac ity and entering temperature, thus enabling the engineer to select the unit best adapted to the heating and ventilating load. Relatively low final temperatures are conducive to the smallest temperature variation throughout a room. Table 36 shows the air handling capacities by the two methods of rating and also approximate heating data. If no direct heating surface (radiation) is installed, the combined heat ing and ventilating requirements must be taken care of by the unit ventilators, and the total heat to be supplied is obtained by means of the following formulae: When all of the air handled by the unit is taken from the outside, fft = 0.24 W y -- <o) W = d60 Q (1) (2) where *Y = n0.2o4a iIiFr "F * (3) d = density of air, pounds per cubic foot. H = heat loss of room, Btu per hour. Hv = heat required to warm air for ventilation, Btu per hour. Ht,= total heat requirements for both heating and ventilation, Btu per hour = H -f- Hv. Q = volume of air handled by the ventilating equipment, cubic feet per minute. I = temperature to be maintained in the room. to -- outside temperature. . ty = temperature of the air leaving the unit, W = weight of air circulated, pounds per hour. 0.24 ~ specific heat of air at constant pressure. From Equations 1, 2 and 3: fft = H + 0.24 d 60 Q (t - to). (4) Example l. The heat loss of a certain room is 24,000 Btu per hour, and the ventilating requirements are 100Q cfm. If the room temperature is to be 70 F and all air is taken from the outside at zero, what will be the total heat demand on the unit if it is required to provide for both the heating and ventilating requirements (combined system)? Solution. H = 24,000; d = 0.075; Q = 1000 cfm; t = 70 F; fo = 0 F. A.S.H.V.E. Standard Code for Testing and Rating Steam Unit Ventilators (A.S.H.V.E. Transactions, Vol. 38. 1932, p. 25). 405 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Substituting in Equation 4: Ht <= 24,000 + 0.24 X 0.075 X 60 X 1000 (70 -0) = 99,600 Btu per hour , = 24,0004-7(1 ss 09 o F y 0.24 X 0.075 X 60 X 1000 + When part of the air handled by the unit is taken from the room and the remainder from the outside. Ht = 0.24 W0 (/y -- A>) + 0.24 Wi (b ~ 0 where Wo = weight oi air, pounds per hour taken from out-of-doors. Wi = weight of air, pounds per hour taken from the room. Wo = do 60 Qo Wi = di 60 Qi where' do = density of air, pounds per cubic foot at temperature L>. di = density of air, pounds per cubic foot at temperature t. Qa = volume of air taken in from the outside, cubic feet per minute. Qi = volume of air taken in from the room, cubic feet per minute. ff ' h = 0.24 (W0 + Wi) + 1 (5) (6) (7) (8) Ht = H + 0.24 do 60 Q,, (t - lo) (9) Equations 5, 6, 7, 8, and 9 may be used in the same manner as is illustrated above for Equations 1, 2, 3, and 4. It may be noted in Equa tion 9, representing the total heat requirements, that as the quantity Qa is diminished the heat requirements for the unit diminish very materially. , In Example 1, if the quantity of air taken in from the outside is reduced to zero, or all of the air handled by the unit is recirculated, the total heat requirements Ht reduce from 99,600 to 24,000 Btu per hour, or to about one fourth. Such a unit handling one third of its air volume from the outside and two thirds from the room would show a total heat require ment of 24,000 -f- _--24,000 _ 59200 Btu per hour. Units designed and operated on this principle show an average heat requirement and, therefore, a boiler capacity requirement of less than 50 per cent of that required for units taking all their air from the outside. If all of the air is recirculated, the total heat required is the same as the heat loss of the room, or . - Ht = H = 0.24 W (fy - 1) (10) If the heat loss of the room is to be taken care of by the direct heating surface, the unit ventilators will be required to warm the air introduced for the ventilating requirements. Therefore: ff, = 0.24 W (ly - A.) . (11) In this case ty should be equal to or slightly higher than t. If the unit ventilator were of such capacity as to exactly provide for the ventilating 406 CHAPTER 22, UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS requirements, the direct radiation would be selected on the usual basis. However, it is necessary to employ a unit which may not exactly meet the ventilating requirements, since standard units are usually rated in terms of the volume of air that will be delivered at a certain temperature ty for an initial temperature of tQ. Therefore a certain amount of heat (Ht) may be available from the unit ventilator for heating purposes, as pre viously stated, and the amount of equivalent direct heating surface may, if desired, be deducted from the amount required for heating the room. Applications Items to be considered in the application of unit ventilators include the following: 1. Combination with other means of heating. 2. Location of units. 3. Method of venting. . In a split system the unit is used primarily for ventilation. Air is delivered to the room at very near the room temperature, and enough separate direct heaters are placed in the room to warm it to the desired temperature, independently of the unit. Their principal advantage lies in offsetting the cooling effect of window and wall surfaces long before these can be heated to room temperature and in retaining heat for this purpose after the ventilation is shut down. Where the unit ventilator selected has a capacity more than sufficient to warm the air needed to meet the ventilating requirements, a corre sponding reduction may be made in the amount of direct heating surface installed. The greater the amount of excess capacity of the unit, the more efficient will be the temperature regulation of the room. The split system permits the heating of the room during failure of electric current, since the direct radiators will furnish heat, but it permits a careless oper ator to avoid operating the ventilating equipment. A combined system employs the unit ventilator alone, its capacity being sufficient both for ventilation and for supplying the heat loss. Direct heating surface is omitted altogether. It becomes necessary then that the fan be running whenever the room is to be heated but this also gives assurance of ventilation, especially if automatic dampers are used in the air intake from out-of-doors and in the recirculating intake arranged so as to give a certain quantity of air from the outside (commensurate, with weather conditions) whenever the unit is operating and after the room is heated. The cost of installation of a combined system is usually less than that of a split system and there is less danger of overheating, but if the electric energy fails there will be practically no heating. The location of the unit ventilator in a room is important. Wherever possible it should be placed against an outside wall. It is difficult to obtain proper air distribution if the unit is erected either on an inside wall or in a corner of the room. Standard units discharge the air stream upward, but . for special cases units may be installed to .discharge air horizontally. Units may be set away from the wall or partially recessed into the wall to save space without materially affecting the results. The air inlet may enter the cabinet at the back at any point from top to bottom. 407 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The size and location of the vent7 outlet is important. In many cases the sizes for public buildings are regulated by law, but the location of the vents generally is left to the discretion of the engineer. Best results have been obtained with a velocity through the vent openings nearly equal to that at which the air is introduced into the room, thus maintaining a slight pressure in the room. Calculated velocities at the vent openings of from 600 to 800 fpm produce the best diffusion results from this system. . The cross-sectional area of the vent flue itself may be figured on the basis of 15 sq in. of flue for each 100 cfm. Thus the vent flue area of a flue for a room equipped with one 1200 cfm unit ventilating machine would be 180 sq in. The area of vent flue opening from the room may be figured on the basis of 25 sq in. per 100 cfm. In school buildings provided with wardrobes or cloakrooms the vents may be so located that the air shall pass through these spaces, heating and ventilating them with air which otherwise would be passed to the outside CHARTER 22. UNIT HEATERS, UNIT VENTILATORS, UNIT HUMIDIFIERS UNIT HUMIDIFIERS A unit humidifier consists essentially of some type of equipment for adding moisture to the air, usually a fan to draw the air through the humidifier, and. in some cases tempering coils and filters, all encased in a single cabinet. These units are generally used in conjunction with heating systems which do not provide the necessary humidification during winter operation. In any type of unit humidifier, the process of adding moisture to the air requires heat from a heating coil, water, or air itself. Fig. 9. Typical Window Ventilator without being used to the best advantage. Many state codes for venti lation of public buildings make this arrangement mandatory. . There has been much controversy over the use of corridor ventilation in school building practice, one group holding the view that when each classroom has a separate vent flue there is a minimum fire risk and less likelihood of cross-contamination, while others emphasize the economy features of the corridor discharge and minimize the fire contamination, and other hazards. WINDOW VENTILATORS A window ventilator consists of filters arid motor driven fans enclosed in a cabinet to be mounted on the window sill of homes or offices. These units accomplish ventilation, air cleaning, and air circulation. The direction of air discharge is manually adjustable for seasonal operation. Fig. 9 illustrates a unit of this type. .. fA.S.H.V.E. Research Report No. 936--Investigation of Air Outlets in Class Room Ventilation, by G. L. Larson, D. W. Nelson, and R. W. Kubasta (A.S.H.V.E. Transactions, Vol. 38, 1932, p. 463). A.S.H.V.E. Research Report No. 1017--Air Supply to Classrooms in Relation to Vent Flue Openings, by F. C. Houghten, Carl Gutberlet. and M. F. Lichtenfels (A.S.H.V.E. Transactions. Vol. 41.1935, p. 279). 408 Fig. 10. Typical Unit Humidifier of the Spray Type for Use in the Room being Humidified Fig. 11. Typical Unit Humidifier of the Spray Type with Steam Coil to Preheat the Air for Residences Types of Units Small unit humidifiers in decorative casings are made for applications where it is desired to place the unit directly in the room to be humidified. These units are usually of the atomizing type and are completely selfcontained. The humidifier water is supplied by a reservoir which must be refilled at intervals. In most units the fine spray of water is mixed with some room air and the mixture is discharged directly into the room. The heat required for humidification in this method is obtained by trans forming some of the sensible heat of the air to latent heat. A unit of this type is illustrated in Fig. 10. Another type of small unit humidifier employs the principle of vapor izing the water by the direct application of heat. One method commonly used is to immerse an electric heating element in a reservoir of water 409 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 to heat it until some of the water is vaporized into the air stream. This type of unit is usually used in the same range of capacities as the spray type described above. A third type of unit humidifier used extensively is the larger spray type of unit to deliver enough humidifying capacity for a residence. In this type of unit either the water or air is heated. Fig. 11 illustrates a typical unit of this type. These units usually include air filters and in some cases provide ventilation air by means of an outside air duct connec tion to the unit. The units are available for either floor or ceiling mounting and are usually placed in a central location in the basement with short supply and return duct connections from the first floor. Room air is brought into the unit through the return duct connection and first passes over a tempering coil heated by steam or hot water, then is humidified by passing through some type of spray humidifier. Surplus moisture is removed by an eliminator and the humidified air is delivered to the room through a duct connection. Since a large percentage of the tempering coil capacity is transformed into latent heat during the humidifying process, the unit does not generally eliminate any existing steam radiation but does tend to improve comfort conditions by supplying heating during the off-period of furnace operation. For a complete discussion of the principles of the various methods of humidification, refer to Chapter 26. < 410 Chapter 23 UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS Unit Air Conditioners, Functions, Types, Application, Cooling Units, Attic Fans AUNIT is an assembly of the functional elements indicated by its name, such as air conditioning unit, room cooling unit, etc. A unit of this type may be complete in itself employing its own direct means of air distribution and source of refrigeration or heating, in which case it represents a complete self-containea unit. Or it may be coupled with separate means of refrigeration and air distribution, in which case it will still be considered a unit system in comparison with customary field fabricated central station systems. The code, Standard Method of Rating and Testing Air Conditioning Equipment1, defines the various types of unitary equipment: 1. A Cooling Unit is a specific air treating combination consisting of means for air circulation and cooling within prescribed temperature limits. 2. An Air Conditioning Unit is a specific air treating combination consisting of means for ventilation, air circulation, air cleaning and heat transfer with control means for maintaining temperature and humidity within prescribed limits. 3. A Cooling Air Conditioning Unit is a specific air treating combination consisting of means for ventilation, air circulation, air cleaning and heat transfer with control means for cooling and maintaining humidity within prescribed limits. 4. A Self-Contained Air Conditioning or Cooling Unit is one in which a condensing unit is combined in the same cabinet with the other functional elements. Self-contained air conditioning units are classified* according to the method of rejecting condenser heat (water cooled, air cooled, and evaporatively cooled), method of introducing ventilation air (no ventilation, ventilation by drawing air from outside, ventilation by exhausting room air to the outside, or ventilation by a combination of the last two methods), and method of discharging air to the room (free delivery or pressure type). 5. A Free Delivery Type Unit takes in air and discharges it directly to the space to be treated without external elements which impose air resistance. 6. A Pressure Type Unit is for use with one or more external elements which impose air resistance. UNIT AIR CONDITIONERS This equipment takes the form of an encased assembly including the apparatus necessary to perform either some or all of the functions of Prepared by a Joint Committee of the American Society of Refrigerating Engineers, American Society or Heating and Ventilating Engineers, Refrigerating Machinery Association, National Electrical Manu facturers' Association and Air Conditioning Manufacturers' Association. Standard Method of Rating and Testing Self-Contained Air Conditioning Units for Comfort Cooling prepared by a Joint Committee of the American Society of Refrigerating Engineers, American Society Ok Heating and Ventilating Engineers, Refrigerating Machinery Association, National Electrical Manu facturers' Association, and Air Conditioning Manufacturers' Association. 411 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 cooling, dehumidifying, filtering, ventilation, air circulation, heating, and humidifying. Control of the air conditions is provided by manual switches, automatic devices or a combination of the two. The controls are usually mounted on the units. The various elements required to produce the effects on the conditioned air are discussed herewith under separate headings. Heating Heating in the air conditioning unit is ordinarily accomplished by a heating coil of the non-ferrous finned tube type supplied with either steam or hot water. The steam or hot water is supplied from an external source. In some cases the heating element may be an electric heater. Where electric power is low in cost, air conditioning units may provide heat from encased or open strip heaters (see Chapter 41). Radiant electric heaters are seldom used except as their radiant heat is absorbed by some receiving wall and then transmitted to the air in the form of convected heat. Humidifying Humidifying the air requires a source of heat which may be supplied by applying heat directly to the humidifier water, by applying heat to the air to be humidified, or by picking up heat directly from the air. The oldest and best known method of humidifying air is by means of a spray. The simplest system is that in which the spray water is furnished from a constant water source, and the excess is permitted to run to waste. The spray effect may be accomplished either by a direct atomizing type which breaks the water down into fine particles by passing it through . nozzles, or the water may be directed in a fine jet to a flat surface or target. In these methods some of the sensible heat of the air is trans formed into latent heat. These methods are normally inefficient in the use of water. In some cases, the spray is impinged against a heated surface, thereby evaporating some of the water to increase the humidi fying capacity. While this is practical in some instances, there is always the danger of scale formation where hard water is employed. A direct steam spray is used in industrial applications but is seldom used in air conditioning units for comfort work due to the resulting odors. ' A popular method is to use a drip humidifier. In this type, the water flow is controlled by a solenoid valve and the water is poured into a pan. The pan contains a series of small holes through which the water passes and drips over a built-up section of galvanized screening. The air passes through the screens and picks up moisture. Another method of humidifying is the evaporative pan type. This is used in comfort conditioning units and consists of a container offering as . much water surface as possible and equipped with means of heating the water. The heat may be applied either electrically, by steam, hot water, or by circulation of the water from a heated space through the evaporating pan. Since the humidification is accomplished by surface evaporation only, if low pressure steam or hot water is used, it is essential that the air stream be directed across the surface and that the evaporating surface be large. The evaporative pan type of humidification limits the water wastage and is usually supplied with water through a float valve. 412 CHAPTER 23. UNIT AIR CONDITIONERS, COOLINC UNITS, ATTIC FANS Due to the collection of salts in this evaporating pan such humidifying systems require occasional drainage and cleaning. Other methods of humidification attempted in air conditioning units are through the use of wetted fabrics, porous earthenware plates, or other capillary surfaces. These methods rely upon the.capillary absorption of the moisture up from the liquid level into the portion exposed to the air. They have a tendency to lose their effectiveness due to the resulting deposit of mineral salts at the evaporating surfaces thereby clogging the pores and reducing the contact of the air with the water. Also they frequently become foul and often support bacterial growth. Cooling and Dehumidifying The cooling and dehumidifying effects on air are produced either simultaneously as in the case of a direct expansion cooling coil, or sepa rately as in the case of an adsorption process and separate cooling coil. In conditioning units, the use of surface cooling is probably the most common method of producing reduction in dry-bulb temperature of the. air and dehumidification simultaneously. The type of surface employed may be cast or fabricated from tubes. In present day practices finned tubes or plate fins through which tubes are passed form the most generally used cooling surface. The detailed fabrication of this surface and the arrangement of the tubes will depend largely upon the type of refrigerant for which it is intended. ' The simplest construction is that in which chilled water or brine is used as the refrigerating medium. With direct expansion refrigerant it is usually necessary to provide a special arrangement of headers so that proper distribution of refrigerant through all the surface is obtained. In some cases, ordinary brine coils can be used when operated as a flooded refrigerant system. In some units a combination of a direct spray and a refrigerant surface is used, the spray being directed against the surface. Such systems claim the advantage of air washing together with the maintenance of a clean and effective cooling coil. When suface coolers are used, adequate protection in the form of filters or at least lint screens are necessary to prevent fouling of the surface from the air borne dirt. Surfaces not so protected frequently becomes completely matted'with lint,, grease, and similar dirt. The sources of refrigeration used with these surface type conditioning units are discussed in Chapter 24. However, they may be divided into the following groups: 1. Direct expansion refrigerant in which the liquid refrigerant is evaporated within the coils of the unit. The vapor from these coils may be recompressed in centrifugal, rotary, or reciprocating type compressors, and the refrigerant again returned to the evaporator coil. 2. Indirect refrigeration by means of: a. Cold well water. b. Cold city water. c. Artificial refrigerated water provided by direct expansion of refrigerant in a water cooler, direct steam jet refrigeration, or by the melting of ice. Another direct means of cooling and dehumidification is through the use of ice. In such units the ice is brought into as intimate contact as 413 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 possible with the air handled. Provision is made for the removal of the moisture as rapidly as it is formed from the melting of the ice. Ice is also used to cool water which is circulated through the sprays. Other methods of dehumidification accomplished by direct contact with the transfer medium are by means of the so-called adsorption and absorption systems. (See Chapters 2 and 24.) It must be recognized . that these methods of dehumidification do not in themselves provide . cooling. The substance removes the water vapor from the air thereby heating it. This highly dehumidified air may then be cooled either by partial rehumidification or by direct contact with a cooling medium of cold water or direct expansion refrigerant. Filtering The filtering or air cleaning function of an air conditioning unit is accomplished in a variety of ways depending upon the amount of filtering required. In unit systems where filtering alone is considered satisfactory, WINDOW ADAPTER CONDITIONING FAN ROOM-AIR FILTER .CONDENSER SURFACE CONDENSER-AIR FAN Fig. 1. Self-Contained Room Type Air ConditRining Unit for Cooling the degree of filtering varies widely and in proportion to the actual needs. If the air is chiefly recirculated with but little outside air used for venti lation, filtering requirements are largely limited to keeping the coils in a clean and operable condition. Thus such units are frequently furnished with simple lint screens of low resistance and formed of moderately close meshed wire. Where outside air is used for ventilation, more complete filtering of dust particles is necessary and for this purpose, there are a large number of filters available on the market. Some of these filters are of the so-called throw-away type, constructed of inexpensive material so that when they become dirty or clogged they may be thrown away and replaced with new ones. All of these filtering methods are described in detail in Chapter 27. Ventilating The ventilating function or introduction of outdoor air is an important consideration in air conditioning units for comfort cooling. While a unit that recirculates all its air capacity is still considered an air conditioning 414 CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS unit, the better type system provides for the introduction of a certain proportion of outdoor air. In some instances one of several units may operate entirely on outside air, while in other cases only a portion of the air handled by the unit is drawn from out-of-doors. In such cases a damper is provided either in the unit or in the duct connections for con trolling the proportion of outdoor air. Types of Units Several types and designs of air conditioning units are available for selection. New designs are constantly appearing, with new improve ments, greater capacities, wider range of application, and superior construction. Air conditioning units may be classified into the fol lowing types: L. Self-contained air conditioning units. a. Room air conditioners for mounting either on the floor or window sill. The condensers are either air, water, or evaporatively cooled, b. Store air conditioners for mounting either inside the conditioned space and discharging air directly from the unit, or located outside the conditioned space with ducts connected to the unit. The condensers in this type of unit are water cooled. . 2. Remote air conditioning units. These may be either the suspended type or floor type. Design of the floor type of unit varies depending upon the type of application. Units for multiple installation in office buildings or hotels, units for individual offices, and commercial refrigeration units are some of the varieties manufactured. The self-contained room air conditioning units are finished in deco rative cabinets to harmonize with the interiors of residences or offices. For the operation of this unit it is only necessary that it be located adjacent to a window or shaft to which air connections can be made and to plug in the motors to a convenient light socket. A unit of this type is illustrated in Fig. 1. In this particular unit, the conditioned air enters on the side, passing through a grille, filter, and cooling coil, and is de livered vertically to the room through a special motor and fan assembly. Refrigeration is furnished by a reciprocating compressor driven from a motor located in the base. This compressor utilizes an air cooled con denser. Air is drawn into the base by a fan mounted on the compressor motor, so arranged that the air passes through the refrigeration condenser and is again discharged out through the window connection. A novel feature of this design is that the condensate from the cooling coil is sprayed over the condenser surface and there vaporized, thus eliminating the need for drain connections. . One advantage of this type of con ditioning unit is that it may be removed from the occupied space during the winter season when cooling is not needed. . Other self-contained room air conditioners are available with water cooled or evaporatively cooled condensers. In the water cooled unit, a water connection and drain must be made to the unit, thus reducing the mobility of the unit. The evaporative cooled condenser model also requires a small water connection to supply the necessary water to evaporatively cool the condenser. Self-contained room air conditioners have been made in sizes from % to i-Vl hp. The K and hp sizes are usually window type units with air. cooled condensers. 415 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Self-contained air conditioning units for stores and other commercial establishments have achieved prominence in the last few years. These units range in capacity from 1 to 15 hp. The equipment is enclosed in steel casings and in sizes up to 10 hp is finished to harmonize with the interior of commercial establishments. The units use water cooled condensers and are designed for floor mounting. Units in sizes up to and including 5 hp usually include, air distributors to discharge the air directly into the conditioned space, thus eliminating the cost of duct work. The air distributors are adjustable to direct the air flow in such a manner to provide even air distribution in the space being conditioned. These units may use 100 per cent recirculated air or may supply quantities of ventila tion air by means of a duct connected from outdoors to the inlet of the unit. CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS conditioned space is to pass some of the recirculated air through the condensing unit compartment then up into the air conditioner section. This method reduces the net cooling effect of the unit since some of.the cooled air is used to remove heat from the condensing unit enclosure. Store units usually provide for the inclusion of heating coils and humidi fying equipment as optional equipment where winter ventilation and circulation are desired. . A typical self-contained store air conditioning unit is illustrated in Fig. 2. In this particular unit the air enters a grille located at the front of the unit, passes through a filter, and is discharged by a blower through a cooling and heating coil to an adjustable discharge distributor. The air is delivered in a manner to insure good distribution without being directed at the occupants. In some designs the air may be discharged Fig. 2. Self-Contained Store Type Air Conditioning Unit Self-contained store units above 5 hp are usually'located adjacent to the conditioned space and ducts connected from the unit to outlets in the conditioned space. This is necessary because it is not usually possible to evenly distribute the large volumes of air handled by these units from a single air distributor. The larger units are therefore not as decoratively finished since they are placed outside the conditioned space. Another problem in the design of these units is to provide a means of removing the heat of compression and the heat of the motor from the unit. This may be done by a small water cooled cooling coil placed inside the condensing unit compartment. The same water is passed through the water cooled condenser. In the larger sizes, the enclosure around the condensing unit is perforated or screened so that the ambient air removes the condensing unit heat. This is possible since the units are placed outside the conditioned space and appearance of the unit is not a major factor. A third method used with units located in the 416 Fig. 3. Vertical Remote Type Air Conditioning Unit, Year 'round from the sides of the unit as well as from the front. The refrigerating effect is furnished by a reciprocating compressor belt connected to a motor, all mounted on a resilient base to reduce vibration. The heat dissipated by the condensing unit is generally removed by water cooling. Panels are removable for servicing and replacement of filters. The motor starter and other controls are mounted inside the enclosure and the unit may be operated either as a cooling unit or circulating unit by using the manual switches mounted on the side panel, or it may be automatically controlled by means of a thermostat. Remotely located air conditioning units vary widely in details of construction and. are different from the self-contained type of unit in that the sources of refrigeration or heating are not enclosed in the unit. The vertical floor type remote unit shown in Fig. 3 consists of a fan section, housing one or more fans, mounted on a coil section in which are located a heating coil and a cooling coil, which may be built for 417 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 either direct expansion refrigerant, chilled water, or brine. These two sections are supported on a third or drip pan section. The distributing duct system is attached to the fan outlets and return and outside air con nections are made to the drip pan. A filter box is illustrated attached to the drip pan section. A horizontal remote type of air conditioning unit is illustrated in Fig. 4. This unit is similar in construction and operation to the vertical type explained previously. In the smaller sizes this type is installed in the Fig. 4. Horizontal Remote Type Air Conditioning Unit, Year 'round as -*r. ;' CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS ' ventilation through short full-size ducts. Similar units are available with twin housed fans of the same general construction, although usually such fans draw the air instead of blowing it through the coils. A spray type remote conditioning unit is illustrated in Fig. 6. This spray type unit, which is similar to the arrangement given in Fig. 3, provides for the complete washing of the air and the cooling coil. For winter operation the spray provides means for humidification. The units may be obtained with by-pass dampers as shown in Fig. 6, to provide control of cooling in summer and humidification in winter. The spray type unit without the cooling coil may be used for humidification and heat control. This type of air conditioning unit is used in industrial process air conditioning as well as for comfort air conditioning. All of these, types of remote air conditioning units are usually located DtS^KARQE iI ^^coHKOeUcCnToH Fig. 5. Suspended Propeller Fan Type Cooling Air Conditioning Unit ' conditioned space discharging the air directly from an air distributor. A common type of suspended unit for exposed location utilizing a propeller type fan and suitable for summer conditioning only is illustrated in Fig. 5. Such units are equipped with either a direct expansion coil or one for chilled water or brine circulation. The outer cabinet is made of wood-grained steel or baked enamel and is insulated from the cool air chamber to prevent external condensation. The drip from the coil is collected in an insulated drip pan and carried to a drain. The inlet to the unit is provided with a lint screen to protect the cooling surface. Such units are normally used for recirculation only but may be connected for 418 Fig. 6. Spray Type Remote Air Conditioning Unit outside the conditioned space with duct work from the unit to the con ditioned space and are used mostly in commercial application. Another type of remote room air conditioner is the type used for multiple installations in office buildings or hotels. An all-year-round floor type remote heating and cooling unit for an exposed location and with direct expansion coil supplied with refrigerant from a remotely located compressor is shown in Fig. 7. A cooling coil for use with chilled water may be substituted for the direct expansion coil indicated. The fans below the separate cooling and heating elements deliver the air against deflectors thereby obtaining distribution across the face of the element and preventing condensate from dripping down into the fans. The plate upon which the fans are mounted serves as the drip pan from which the water is conducted to the drain. Separate elements are used for heating and cooling without manual control. When the unit is used for summer conditioning only, the heating coil may be omitted. The illustration indicates an evaporative type humidifier and drain pan. 419 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Other units are available in which a target spray humidifier is substituted for the evaporative type thereby supplying humidification in winter for application in rooms with other existing heat sources. However, this spray will not provide a great deal of humidification unless the water or air passing through the unit is heated. Still another remote type of unit is available in which the fans are mounted at the top of the unit delivering directly through a grille and drawing their air supply through the cooling and heating coils. Other variations in proportion and details of construction of this general arrangement are common: With this type of unit, ventilation is usually provided by means of a separate duct connected to the inlet of the unit. An entirely different arrangement of the remote air conditioner for multiple installation is shown in Fig. 8. This places both the air inlet and the discharge at the top of the unit. The fan at one side discharges the air downward to the bottom where it turns and passes horizontally CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS In locating air conditioning units, the characteristics of the con ditioned space, the building construction, the type of system employed, the duct connections, the accessibility of the unit for servicing, as well as the sources of power, water, refrigeration, heating, and drain connec tions should be considered. Locating units in the conditioned space demands serious attention to insure proper air distribution. If ventilation air is required, or if the condenser of a self-contained unit is of the air cooled type, the proximity to a source of outdoor air should be considered when locating the units. Self-contained units with water cooled condensers should be placed close to the water supply and drain, and care must be exercised that the ambient temperature is never below 32 F to prevent freezing the water in the condenser. It is, of course, important to locate the unit so that panels may be easily removed so that parts are easily accessible in case of trouble. Fig. 7. Floor Type Remote Room Air Conditioning Unit for Heating and Cooling through an atomizing spray air washer. The path then continues upward through eliminators, a cooling surface and a heating surface before it leaves the unit. With steam or hot water connected to the heating element, this unit gives controlled temperature, humidity, air cleaning, and air movement in both summer and winter. Excess water is run to waste. Acoustical treatment of the housing and outlet baffles permits installation where noise requirements are exacting. Application In the application of unit air conditioners it is important to consider the following points: 1. Location of the unit. 2. Air distribution. 3. Use of multiple units in lieu of a central plant system. 4. Self-contained units vs. remote air conditioners. 5. Water usage of self-contained units and methods of water conservation. 420 Fig. 8. Remote Type Room Air Conditioning Unit with Top Inlet and Outlet Location of the remote type of unit also requires consideration of the source of refrigeration or heating. In the smaller sizes these units are placed in the conditioned space. The larger sizes are frequently located externally to the occupied and conditioned space and are connected thereto by means of delivery and return ducts. Such an arrangement permits the location of the conditioning unit convenient to either the source of refrigeration or outside air or both. It frequently permits the use of the basement or of space less valuable than that on the level or floor of the occupied zone. The design then approaches that of a Central System, (see Chapter 21). Oftentimes the same type of unit may find application in an exposed position for one job and in a concealed location for another. Frequently conditioning units are built into the structure or into the architectural design of a room so that they are entirely concealed except for the discharge and return grilles which are designed so as to correspond to the decorative scheme of the room. 421 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Air distribution with self-contained room air conditioner or remote room air conditioner exposed in the conditioned space is usually through grilles or louvers built into the equipment. The grilles or louvers, are adjustable to assist in directing the air properly. The discharge of the air from this type of unit is directed upward at some angle with respect to the horizontal so that the cool air is not directed at the occupants, but at the same time is carried to the most remote part of the room. In general, the air discharge should be designed to distribute cool air over the entire zone, dropping slowly and returning to the unit below the breathing line and along the floor. The location of doorways, air vents and heat-exposed walls should be carefully observed as they have a marked effect on the direction of air flow and on its uniformity of temperature. . .. Air distribution with the suspended remote air conditioner in the conditioned space requires attention to outlet air velocity. Sufficient air velocity should be provided to give adequate induction and mixing with room air thereby preventing the immediate dropping of the air stream and resulting objectionable cold drafts. Air distribution with units, either self-contained or of the remote type, located outside the conditioned space is provided by ducts and outlet grilles. The location of these outlets is quite critical and is influenced both by the building construction, economies of connections, and by the distribution of load. There are a wide variety of outlet types used, and most of these have fixed delivery characteristics, thus requiring careful consideration in their location. Some types of outlets are now available with adjustable vanes thereby permitting some alteration in the delivery of the air stream after installation. This frequently eliminates objection able down drafts resulting from the impingement of the air stream against posts, pillars, lighting fixtures, and beams. Refer to Chapter 29 for a complete discussion of this type of air distribution. Multiple remote units are sometimes used in lieu of a central plant system in installations for large office buildings or hotels. These units, with a centrally located refrigeration or heating source provide the advantages o'f individual room control by the occupants, use. of less floor space since only piping lines need be run and no large ducts are required from floor to floor, and provide better fire protection since the absence of ducts prevents smoke or fire from being transmitted from one room or floor to another. . Self-contained units sometimes provide distinct advantages over remote units. Where the units are located in the conditioned space, the selfcontained unit does not'have any refrigerant or heating connections from an outside source and hence is more easily installed, makes a better appearance and is more easily removed if the owner wishes to relocate the equipment. When the units are located adjacent to the conditioned space, the self-contained units will use less total floor space than the remote type of system besides requiring less installation expense, due to the absence of refrigerant or steam piping. The amount of water used in water cooled condenser types of self- contained units is sometimes an acute factor in application. Self-con tained store units are almost universally water cooled. There are two types of water conserving equipment that can be used with a condensing unit; (1) a cooling tower, and (2) an evaporative condenser. 422 . CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS ;^wuug -- -----------------j -- w uuc store conditioning unit in the same manner as they are applied to other condensing units. When the condensing unit enclosure is cooled by a water coil, the cooling tower must have enough capacity to supply both the water cooled condenser and water cooling coil. The condenser and water coil are placed in parallel to reduce the pressure drop. . Evaporative condensers can be applied to store units if the heat of the condensing unit is removed by recirculated air or a refrigerant coil, and if the.water cooled condenser can be omitted and deducted from the price of . the store cooler. In the case of a unit employing a water cooling coil to remove the heat from the condensing unit enclosure, the use of an evapo rative condenser is uneconomical because a separate supply of water Table 1. Standard Rating Basis for Self-Contained Air Conditioning Units Functions All Cooling Ttpes o? Units Rahko Condition All Water-Cooled, Air-Cooled and Evapora tively Cooled Condensers Water-Cooled Condensers Air-Cooled and Evapora tively Cooled Condensers Item Description a Barometric Pressure b Unit Ambient and Air Entering Room--Air Inlet (1) Dry-Bulb (2) Wet-Bulb c Ventilation Air d Water Temperature Entering Unit e Water Temperature Leaving Unit ,f Air Entering Outside Air Inlet (1) Dry-Bulb (2) Wet-Bulb Value 29.92 in. Hg. 80 F 67 F See Note 75 F 95 F 95 F 75 F Heating g Unit Ambient and Total Air Enter ing Unit 70 F All Types Provided h Heating Medium, Pressure or with Heating 1 emperature Function (1) Dry Saturated Steam 16.7 lb per (2) Water In (3) Water Out sq in. abs 180 F 160 F A 11 T.y p e s Humidifying Humidifying Function i j Air Circulation All k Unit Ambient Total Air Entering Unit (1) Dry-Bulb (2) Wet-Bulb Filters 70 F 70 F 53 F New and Clean """ r wei-ouiD temperature. (The material not pertinent to this chapter.) Hi i - wuc 423 ueen wuucusea in oraer to remove HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 must be supplied to the condensing unit enclosure cooling coil, thus defeating the purpose of the evaporative condenser to conserve water. Ratings . There are two codes governing the rating and testing of air con ditioning units. The first code, Standard Method of Rating and Testing Air Conditioning Equipment3, covers all types of air conditioning units except the self-contained type. The latter is covered by the Standard Method of Rating and Testing Self-Contained Air Conditioning JJnits for Comfort Cooling4. The two codes are necessary because of the basic difference caused by the heat given up by the self-contained units. Self-contained air conditioning unit ratings are expressed in the code in terms of the effect produced on air such as: ' 1. The net total room cooling effect in Btu per hour. This is the actual fieat removed from the room and is equal to the gross cooling effect less the heat given back to the room by the unit. 2. The net room dehumidifying effect in Btu per hour. 3. The net room sensible cooling effect in Btu per hour. 4. The sensible heating effect in Btu per hour. 5. The humidifying effect in pounds per hour. 6. The total air capacity in cubic feet per minute of standard air. The standard rating basis as given in the code for self-contained units is tabulated in Table 1. The standard rating basis for air conditioning units is similar to that given above for self-contained units except the relative humidity of the entering air is specified as 50 per cent (66.7 F wet-bulb) instead of speci fying the wet-bulb temperature as 67 F and the suction saturated re frigerant temperature is specified as 40 F for comfort cooling since an air conditioning unit does not include a condensing unit. The suction saturated refrigerant temperature of a self-contained air conditioning unit is not given in Table 1 as a basis of rating since this temperature is the temperature obtained when the self-contained unit operates as a system at the conditions given in Table 1. It is expected that the entering air conditions for the standard rating will agree when the code, Standard Method of Rating and Testing Air Conditioning Equipment, is revised. COOLING UNITS Cooling units may be used either in comfort cooling or commercial applications. As applied to industrial product conditioning and pro cessing they are similar in construction to unit heaters described in Chapter 22 except that the heat transfer surface is supplied with refriger ation instead of heat. They are normally installed within the space to be served, or at least closely adjacent thereto. Product cooling was originally accomplished by means of stationary pipe coils. This was later supplemented with the forced fan bunker systems in which air was passed over banks .of coils. Today the coils* *Loc. Cit. Note 1. <Lo<\ Cit. Note 2. 424 CHAPTER 23. UNIT AIR CONDITIONERS, COOLING UNITS, ATTIC FANS . and fan are encased in an enclosure and controls are provided to maintain an average coil surface temperature. Thus, for any installation, the depth of coil, air flow, and face area determine the relation between dry-bulb temperature reduction and wet-bulb temperature reduction. Occasionally they are provided to receive outside air in which case this air is invariably filtered or washed to prevent any possible contamination of the product. Features of Units The principal field for cooling units is in cold storage plants, fur storage, fruit packing houses, provision stores, brewery fermentation and stock rooms, candy plants, and other industrial process work. In replacing bunker and wall coils in meat storage plants, cooling units give distinct advantages in compactness, lower first cost and maintenance expense, ease of defrosting, freedom from drip and the maintenance of sanitary conditions, as well as uniform temperature and humidity under variable load conditions.. Cooling units by means of their positive air circulation prevent dead-air spots, frequently objectionable in this industry. Types of Units Cooling units are provided in two major types similar to unit heaters, either floor mounted with housed fan, or suspended with propeller type fans. Normally, air outlet velocities are lower than for heating, due largely to the effect of high velocities on the product, Cooling units are normally of the. free delivery type although they occasionally are supple mented with duct work to. provide more careful air distribution. Typical cooling units are shown in Figs. 9, 10, and 11., Fig. 9 indicates a suspended type cooling unit which may be designed with or without a moisture eliminator. If high air velocities are maintained, an eliminator will be necessary to prevent the drops of moisture from being carried through with the air. The condensation that occurs is collected in a drip pan and removed from the system through a drain pipe'. Fig. 10 indicates a typical floor-mounted unit of the housed fan type. The illustration shows a common form of distributing outlet designed to give low outlet velocities together with a controlled distribution. In process work, it is 425 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 23. UNIT AIR CONDITIONERS. COOLING UNITS, ATTIC FANS often important that direct air distribution does not impinge on the product. Cooling units are normally constructed of galvanized steel or non-ferrous material in order the reduce the corrosive effect of their constant wetted condition. i1; Ratings Since cooling units are mostly used in low temperature applications, the standard basis of rating is different than for air conditioning units. The Standard for Rating and Testing Air Conditioning Equipment state that the standard rating shall be based on air entering the cooling unit at 45 F dry-bulb and 85 per cent relative humidity, and the suction saturated refrigeration temperature shall be 30 F for commercial cooling. 1. When the room is above freezing the source of refrigeration is cut off and the fan allowed to operate until the unit has defrosted. 2. A reversal of the refrigeration system may be provided and the so-called hot gas defrosting method used. This is accomplished by reversing the flow of the hot gas so that it is delivered directly from the compressor to the evaporator cooling unit. As soon as the ice and frost has been melted, the system is again returned to its normal cycle. 3. Where brine is used as a refrigerant, heated brine may be sent through the cooler to remove the ice, 4. When the room is at very low temperatures, warm air defrosting is sometimes used by providing for the admission and removal of warm air from outside the cooled space. 5. The surface may be sprayed with a strong brine solution. In order to prevent the collection of frost in low temperature rooms where high latent heat loads are present, unit coolers equipped with a constant brine spray are frequently used. These are normally of the housed fan type similar to Fig. 10, but equipped with a pump for recircu lating brine at intervals to maintain a non-freezing mixture as shown in Fig. 11- COSTS The following factors influence the cost of unit air conditioning in stallations: 1. Since the cost of the total job involves material cost plus installation labor and since through the use of unitary equipment, material costs can be kept to a minimum, every effort should be made to simplify installation. 2. Self-contained units in the small sizes now available, probably represent the lowest cost individual installations. They have, however, their limitations. 3. The floor type all-year-round air conditioning units for the occupied space with a remotely controlled compressor, heating sources being either the existing heat system or steam connections to the unit, probably afford the lowest cost all-year-round service for most individual rooms. 4. For multiple rooms or offices, the remotely located air conditioning unit with remote source of refrigeration probably represents the most economical installation. The larger self-contained air conditioners are particularly adaptable to stores, residences and small commercial installations. Fig. 10. Surface Type Cooling Unit Fig. 11. Brine Spray Type Cooling Unit Ratings of cooling units may be expressed in Btu.per hour, or in tons of refrigeration. When ratings at other than standard conditions are given, the quantity, temperature, and relative humidity of the entering air should be specified, together with the refrigerant temperature within the coil. When chilled water or brine is used, the rate of circulation of the cooling media as well as its entering temperature should be given. Defrosting Cooling units are often called upon to operate in rooms where a tem perature below freezing is maintained and low refrigerant temperatures are required. This results in the collection of frost on the heat transfer surface which in turn leads to a rapid loss in capacity and requires eventual defrosting. Such defrosting is accomplished by the following methods: 426 Costs of operation vary widely depending upon the cost of power and water. Water costs in the larger installations are being materially reduced through the use of cooling towers and special types of condensers. It is difficult to make any comparison of operating costs of cooling as contrasted with heating equipment because the relative operating expense depends upon many factors including climatic conditions; i.e., in the South the cost of operating cooling equipment greatly exceeds the operating cost of heating equipment, whereas in colder climates where cooling equipment is used about two months per year, the heating costs are probably higher than those for cooling. ATTIC FANS Attic fans, used during the warm months of the year to draw large volumes of outside air through a house, offer a means of using the com parative coolness of outside evening and night air to bring down the inside temperature. 427 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Because the low static pressures involved are usually less than x/% in. of water, disc or propeller fans are generally used instead of the blower or housed types. The fans should have quiet operating characteristics, and they should be capable of giving about 20 to 30 air changes per hour in northern areas. In the South the usual specification requires one air change per minute which provides appreciable air movement in addition to the cooling effect. Types Open attic fans are units in which the fan is installed in a gable or dormer and one or more grilles are provided in the ceilings of the rooms below. Outdoor air, which enters the house through open windows, is drawn into the attic through the grilles, and is discharged out-of-doors by the fan. An attic stairway may be used in place of the grilles. It is essential that the roof and the attic walls be free from air leaks. Boxed-in fans are units in which the fan is installed within the attic in a box or housing directly over a central ceiling grille, or in a bulkhead enclosing an attic stair. The fan may be connected by a duct' system to the grilles in individual rooms. Outdoor air entering through the win dows of the rooms below is discharged into the attic space and escapes to the outside through louvers, dormer windows, or screened openings under the eaves. Location The locations of the fan, the outlet openings, and the grilles should be selected after consideration of the room and attic arrangement in order to give uniform air distribution in the individual rooms served. If the outlet for the air is not on the side away from the direction of the pre vailing wind, openings should be provided on all sides. Kitchens should be separately ventilated because of the fire hazard, and to prevent the spread of cooking odors. Costs The capacity of attic fans is from 3,000 to 30,000 cfm with the trend toward units in the range of capacity from 7,000 to 15,000 cfm. Some typical data on an attic fan installation in an average six room house of frame construction containing 14,000 cu ft and located in the southern part of this country are: Installed cost-............ .......... $100 to $400, average $200 Fan data.................................. 12,000 cfm average, 500 watts input Operating period.--............. April 15 to October 15, intermittently as weather con ditions demand Power consumption.............. 500 kwhr per year for 8 months1 operation - In northern climates the figures would be considerably reduced. A smaller capacity fan can be effectively used and the cost of an installation ranges from $60.00 upwards. 428 Chapter 24 COOLING AND DEHUMIDIFICATION METHODS Air Cooling Processes, Dehumidification Processes, Practical Combination Methods, Compression Systems, Mechanical Refrigeration, Steam Jet System, Condensers, Evaporators, Refrigerant Pipe Sixes, Operating Methods, Adsorption System, Absorption System, Evaporative Cooling, Reverse Cycle, Ice Systems COOLING and dehumidifying are closely related in most air condi tioning work. Usually a reduction in both temperature and humidi ty is necessary to produce comfort. It should be borne in mind that: (1) there is a reduction in moisture content whenever air is cooled below its dew-point, and (2) there is a rise in temperature whenever moisture is removed from air by either adsorption or absorption. Although each can be accomplished separately, cooling and dehumidification must in most cases be considered together, not as two separate problems. AIR COOLING PROCESSES In air conditioning either of two arrangements, or a combination of them, is used to accomplish air cooling. The two arrangements are: (a) surface cooling, where the air is passed across a cold metal surface; and (b) spray cooling,, where the air is .passed through a cold liquid spray, usually water. In either case the surface or the spray liquid must be at a temperature sufficiently low so that heat may be removed from the air. Suitable temperatures for the purpose are obtained by the proper use of: 1. Refrigeration; or 2. Water from a cold natural source such as a well, from melting ice, or from applica tion of refrigeration; or . . 3. Evaporative cooling. The choice of most suitable source of cooling in any specific case will depend on the accompanying circumstances and can be determined only by a thorough analysis made by a competent engineer. . 429 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 DEHUMIDIFICATION PROCESSES Dehumidification may be accomplished in any of three ways, or by a suitable combination of them: 1. By cooling the air below its dew-point temperature thus causing a part of the moisture contained to condense and precipitate. 2. By extracting moisture by adsorption. 3. By extracting moisture by absorption. As in the case of air cooling, the best dehumidification method can be determined only by a complete analysis taking into account all the circum stances of the particular case being considered. In Chapter 2 the nature of the adsorption and absorption processes are explained and the principal properties of the materials used are presented. PRACTICAL COMBINATION METHODS As applied in actual practice these several processes frequently have to be combined in order to produce the desired results. Any or all of the three processes of air cooling listed may be combined with any or all of the three dehumidifying processes to produce both air cooling and de humidification. One form of combination consists of a multi-stage ' method whereby moisture is removed from the air and then the resulting mixture is cooled. Stage methods are common where dehumidification is accomplished by the use of adsorbent or absorbent substances. Another method, and one in common use, is to combine the air cooling and de humidification processes into one step. This is made possible by keeping the temperature of the surface or liquid spray used for cqoling below the dew-point temperature of the air to be conditioned. It is the method most commonly associated with comfort air conditioning in current practice. Still another general method consists of what may be called a parallel-flow method wherein the cooling or dehumidification, or both, may be performed by splitting the air stream, performing the process on part of it and then bringing the two parts back together again. Obviously with so many possible combinations much leeway is left to the designer to determine what shall be done in a practical case. The remainder of this chapter is devoted to a discussion of some of these possible practical methods and the equipment used in applying them. Space does not permit discussing all the great variety possible and only those in reasonably frequent use are included here. Others will occur readily and can be analyzed in a fashion similar to those here treated. COMPRESSION SYSTEMS Comfort air conditioning imposes requirements on refrigeration equipment not usually found in general cooling applications so that specially designed apparatus is often required to replace that normally used for industrial cooling. Standard equipment can be adapted to meet air conditioning requirements but extreme care must be taken to deter mine, the limits of its applicability. In industrial or process cooling systems the load is fairly constant, 9 430 IB] CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS noise in. operation is not of paramount importance, space is available or relatively cheap, and the cooling system is to a great extent separate or independent of other mechanical equipment. By contrast, air condition ing in office buildings, theaters and places of public assemblage requires ' special consideration of all these factors. Space in public buildings is limited, noise interferes with the occupants and the cooling equipment must be adaptable to the other air handling apparatus. Most important, the load fluctuates tremendously and is seasonal. Types of Compressors There are many different types of compressors, a number of refrig erants, different types of evaporators, condensers and arrangements of cycle, and each type has its particular place in usage. Compressors generally used are of the following types: 1. Reciprocating compressors using a volatile refrigerant, 2. Centrifugal compressors. a. Using a volatile refrigerant. b. Using water as a refrigerant. 3. Rotary compressors using a volatile refrigerant. 4. Steam jet or vacuum systems using water as a refrigerant. , Reciprocating compressors are generally used with any low pressure refrigerantsuch as dichlorodifluoromethane, monofluorotrichloromethane, methyl chloride, ammonia and sulphur dioxide. These compressors have been developed to a.point where their efficiency is high and their operation very satisfactory. Relatively low speed operation makes them desirable for general use in large installations. Reciprocating compressors may be vertical or horizontal and either single or double acting. The horizontal double-acting compressor is not generally used in air conditioning, except when carbon dioxide is used' as a refrigerant in the larger industrial systems. Vertical, single acting, encased crank, reciprocating compressors of the uniflow type with valves in the pistons have proven reliable and are used in capacities from 1 hp to more than 100 hp. At present recipro cating compressors are used with more refrigerants than any other type of compression unit. When carbon dioxide is used as a refrigerant, a reciprocating compressor is required because of the extremely high pressures and the relatively high ratio of compression. Centrifugal compressors using monofluorotrichloromethane, methylene chloride or water vapor can theoretically be used with any of the other refrigerants, but the resulting loss in efficiency with the higher pressure gases limits the centrifugal compressor to the refrigerants cited. At the present time centrifugal compressors are limited to air conditioning systems of a minimum of about 50 tons. Centrifugal com pressors are usually built in two or more stages where the compression ratio is high and their design follows closely that of any other centrifugal equipment such as is found in general service pumps and fans. Rotary compressors are expanding in use due to the development of new refrigerants. These units are of four common designs, consisting of rotating elements generally referred to as centrifugal, eccentric, gear and blade types. The rotation of the shafts and blades traps the refrig- 431 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 erant vapor between the moving elements and the case and delivers it to the condenser at the required pressure. The rolling together of. the impellers as in the case of the gear compressor prevents the return of the refrigerant vapor to the low side of the system. Steam jet compressors which are particularly adapted to large tonnage installations are simple, compact, have no moving parts and produce practically no vibration. However, they are not economical for water temperatures much below 40 F or where the cost of generating steam is higher than the cost of operation with other prime movers. MECHANICAL REFRIGERATION While the mechanical refrigeration systems differ in the methods used for compression of the refrigerant vapor, they are fundamentally similar. Heat of Compression Added to Gas CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS Theoretical Mechanical Refrigeration Cycle The complete mechanical refrigeration cycle may be illustrated on the temperature-entropy diagram, and also on the pressure-volume diagram, both of which are shown in Fig. 2. In the theoretical cycle, saturated vapor is drawn into the com pressor at. a and compressed at constant entropy (adiabatically), and is then delivered to the condenser at b. Condensation occurs at constant temperature Tt from b to c with a contraction from the vapor to the liquid volume. The line cd represents cooling from the temperature of the condenser to that of the evaporator by an external cooling means. At the same time, the pressure is lowered to Pi. Evaporation then occurs from d to a at temperature Tu completing the work cycle abcda. Since no external means of cooling the refrigerant liquid is normally available, the Refrigerant vapor usually saturated or slightly superheated, is drawn into the compressor as diagrammed in Fig. 1. It is then compressed and dis charged at a higher pressure to a condenser. The vapor is condensed as it contacts a heat transfer surface over which is flowing a cooling medium such as water, air or a combination of the two. The liquid refrigerant flows to the evaporator through an expansion valve which reduces its pressure and regulates its flow. In the evaporator the refrig erant absorbs heat from the medium which is to be cooled. When this medium is water or brine, the evaporator is known as a water or brine cooler and the refrigeration system, if used for air cooling, is known as an indirect system. When the medium cooled is air, the evaporator is known as a direct expansion cooler and the system is known as a direct expansion system. Fundamentally, the function of the system is to absorb heat at one temperature and pump it to a higher temperature, where it may be re moved by an available cooling medium. In order to conserve refrigerant, virtually all refrigeration systems are completely closed and the same refrigerant is recirculated. 432 Fig. 2. Theoretical Dichlorodifluoromethane (Fi,) Cycles cooling is generally accomplished by evaporation of a portion of the refrigerant. Since the work of expansion is usually used up as friction in the expansion valve, this process is assumed to be carried on at constant total heat, as represented by the line ce on the temperature-entropy diagram. Thus the refrigerating effect is represented by an area eagfe. While the normal theoretical cycle starts with saturated vapor, operation is common at a condition of superheated vapor (as at aj. Moreover, expansion may start either with a mixture of liquid and vapor or with a sub-cooled liquid, as at clt with expansion to et. It is obvious that this latter is desirable as it increases the refrigerating effect. Area aibicdaat represents the work of such a superheated cycle, while the area eiOigi/iei represents the refrigerating effect of the cycle with superheated vapor and sub-cooled refrigerant liquid. ' It will be noted on the pressure-volume diagram the volume of the saturated liquid is indicated by a dotted line close to and parallel to the ordinate. _ In the discussions in this chapter a slight error is introduced by not including all of the work of pumping the liquid from the low to the high 433 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 pressure. This occurs because the liquid line is not a line of equal pressure but of saturation pressures. The error in work per pound of refrigerant figured from total heats, which should be added to the indicated figures is roughly the specific volume of the liquid at the lower pressure and tem perature multiplied by the pressure difference in appropriate units. This error may become of some importance in calculations involving carbon dioxide or in problems involving the liquid of any of the refrigerants, as in figuring expansion valve orifices. Theoretical Work per Pound The temperature-entropy and pressure-volume diagrams are based on one pound of the refrigerant. Likewise, the theoretical work and the refrigerating effects are conveniently based on a pound of refrigerant. The compression work per pound may be found by several methods. The temperature-entropy method starts with state point a. Since the quality of a is known, the heat content of the vapor is known, and also the entropy 5a. Since point b lies near the saturation curve it is customary to assume 5a = 5b and with Ti given, Hb can be determined. If W = work in foot-pounds per pound of refrigerant, then W = (tfb - Ha) X 778 (1) The pressure-volume method starts with state point a, whose pressure and specific volume are known. The work of compression is the adiabatic work of compression from Pi to Pt, plus the work of expelling the vapor at constant pressure Ps minus the external work of evaporation of the vapor to volume Vi at pressure Pi. ^ = ^-xxp1vi[(|i)!L^-i] (2) It is frequently helpful to think of the compression, of the vapor in terms of head. The head may be likened to a vertical column of vapor in which is located the vapor to be compressed. The compression occurs when the vapor is moved down from a level corresponding to Pi to a new . level corresponding to Pi, in equilibrium with the surrounding vapor. If this process is carried on isentropically, the result will be the same as indicated previously. Then if h is the head'in feet, . W=h (3) This relationship may easily be seen from the fact that a small difference of head dh divided by the specific volume of the vapor V is equal to the increment of pressure difference dP. Head is very useful in considering the performance of centrifugal com pressors, which merely substitute a centrifugal for the gravity head. It is also useful in considering problems of fluid flow. In these problems, the head per degree can be obtained either by direct calculation or approximately by dividing the total head by the temperature difference Tt--Ti. The velocity head loss can then be calculated in degrees, using the customary formula V2 = 2gh. 434 CHAPTER 24. COOUNC AND DEHUMIDIFICATION METHODS Refrigerating Effect per Pound The refrigerating effect per pound is computed by the same method, regardless of the type of refrigeration system. The solution is indicated on the temperature-entropy diagram of Fig. 2. Assuming that the vapor leaving the evaporator is saturated, the refrigerating effect in Btu per pound is obtained by subtracting from the heat content of the vapor at temperature X\, the heat content of the liquid at Ti, or if the liquid is sub-cooled, the liquid temperature. Thus, the refrigerating effect in Btu per pound is equal to H* - flc = - He (4) If the vapor entering the compressor is superheated or supersaturated, a correction in the heat of the vapor is made accordingly. The unit of refrigeration is the ion, based on the latent heat of fusion of one ton of- ice in 24 hr. Thus one ton = 200 Btu per minute = 12,000 Btu per hour. Coefficient of Performance The coefficient of performance of a refrigeration system is the ratio of the refrigerating effect to the work of compression, both expressed in the same units. The ideal or Carnot coefficient of performance depends upon the tem peratures Ti and Tt in much the same way as the ideal efficiency of a steam engine depends upon its working temperature, with an inverse relationship. Ideal C. of P. = it -- i 1 (5) Evidently the smaller the compression range, the less power will be required to produce a given refrigerating effect. The theoretical coefficient of performance of actual refrigerants is always less than the ideal due to the tendency of most refrigerants to superheat when compressed, and due to the heat of the liquid which must be removed. The cycle efficiency is the theoretical C. of P. divided by the ideal for the same temperatures. The cycle efficiency usually changes as the compression temperatures change. Practical Cycle Fig. 3 illustrates the pressure-volume and temperature-entropy dia grams for an actual cycle. These diagrams are based upon the com pressor receiving vapor superheated and upon sub-cooling of the liquid going to the evaporator. The theoretical cycle is aibiccieiOj. However, the vapor during compression actually follows line aj)t due to superheating as a result of the inefficient work of compression. The theoretical work of compression is aibicdai. Added to this is the area bibigihibi on the tem perature-entropy diagram which represents the inefficient work of com pression (assuming no compressor heat losses). The sum of these areas represents the total work of the compressor per pound of refrigerant, and the ratio of theoretical cycle work to the actual work represents the over all efficiency. It should be noted that area aibibiai is considered as part 435 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 of the inefficient work and is commonly termed the superheat loss. The refrigerating effect per pound is the same for the practical as for the theoretical cycle, working with the same sub-cooling of liquid and super heSaotiunrgceosf ovfalpoossr, wthhaicthisa,raereuasually recognized as reflected by the overall efficiency referring particularly to reciprocating and rotary systems, are as follows: 1. The superheat loss. 2. A pressure loss to and from the cylinder of the compressor. (The line pressure drop between the compressor and the evaporator and condenser, respectively, is usually taken into account separately in the design of the refrigeration system.) 3. Leakage loss through valves and past pistons is quite small in most compressors. 4. With an oil soluble refrigerant, there may be an absorption loss due to absorption and re-evaporation of refrigerant in the oil of the cylinder. 5. Mechanical losses are always present and are usually a large part of the total. Fig. 3. Practical Dichlorodifluoromethanb (F) Cycles Reciprocating and rotary compressors always take in less-vapor than that which corresponds to the displacement. The overall volumetric efficiency is the ratio of the suction vapor volume to the piston displace ment. On reciprocating compressors part of the loss is the re-expanded volume, at suction pressure, of the vapor which was in the clearance volume. This is expressed by the following equation: , Volumetric Efficiency = X -- --- X " -- 1J (6) where ' ty = clearance volume. ) fd = cylinder displacement volume. The balance of the overall volumetric efficiency is known as the super heat volumetric efficiency even though it includes some other sources of capacity loss. 436 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS The mechanical efficiency of a reciprocating and rotary compressor must be multiplied by the superheat volumetric efficiency to give the overall efficiency of the compressor. . Eff.overall = VoL Eff^zp~ X Mch- Eff. = Super. Vol. Eff. X Mech. Eff. (7) Normally, the volumetric efficiency of a compressor varies with the ratio of compression, while the mechanical efficiency remains virtually fixed. Good standard practices for dichlorodifluoromethane compressors are: Vol. EfT.reeip* Vol. Eff.super* Vol. Eff.overall Mech. Eff. Low comp, ratio = 2.5 to 1 94 to 96 per cent 75 to 85 per cent 70 to 81 per cent 75 to 85 per cent High comp, ratio = 5 to 1 88 to 92 per cent 73 to 77 per cent 64 to 71 per cent 75 to 85 per cent These values are for one ton or larger compressors. Part of the dif ference expresses the change with capacity. With other refrigerants and other types of compressors there will be some further variation. STEAM JET SYSTEM The steam jet type of compressor, under certain circumstances, is desirable for use in air conditioning. The power used for compressing the refrigerant is steam, taken directly from the boiler, thus eliminating the mechanical losses of manufacturing electric current. As the com pression ratio between the evaporator and condenser under normal circumstances is large, the mechanical efficiencies of the equipment are somewhat lower than those of the positive mechanical type of compressor; also the condensing water requirements are considerably greater, as both the refrigerant and the impelling steam must be condensed. The steam jet system functions on the principle that water under high vacuum will vaporize at low temperatures, and steam ejectors of the type commonly used in power plants for various processes will produce the necessary low absolute pressure to cause evaporation of the water. A diagrammatic representation of a typical steam ejector water cooling system is shown in Fig. 4. The water to be cooled enters the evaporator and is cooled to a temperature corresponding to the vacuum maintained. Because of the high vacuum, a small amount of the water introduced in the evaporator is flashed into steam, and as this requires heat and the only source of heat is the rest of the water in the evaporator tank, this other water is almost instantly cooled to a temperature corresponding to the boiling point, determined by the vacuum maintained. The amount of water flashed into steam is a small percentage of the total water circulated through the evaporator, amounting to approximately 11 lb per hour per ton of refrigeration developed. The remainder of the water at the desired low temperature is pumped out of the evaporator and used at the (joint where it is required. The ejector compresses the vapor which has been flashed in the evaporator, plus any entrained air taken out of the water circulated, to a somewhat higher absolute pressure, and the vapor and air mix with the impelling steam on the discharge side of the jet. The total mixture of 437 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 entrained air, evaporated water, and impelling steam is discharged into a surface condenser at a pressure which permits the available condensing medium to condense it. The resulting condensate is removed from the condenser by a small pump, from which it can be discharged to the sewer * % or returned to the system in the form of make-up water, or part of it may be returned to the boiler feed pump. The slight amount of air which may be entrained in the cooled water is removed by a small secondary ejector which raises the pressure sufficiently so that the air can be discharged to the atmosphere. A small secondary condenser, of course, is necessary to condense the steam used in the secTohnedapreyrjfeortm. ance of the steam ejector may be studied theoretically by the use of the temperature-entropy diagram, Fig. 5. Unlike its usual 438 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS application, however, the amount of working fluid is different for one portion of the cycle than for the other. Dry saturated steam under high pressure, for example 100 lb per square inch gage, at a, is expanded through the nozzle of the steam ejector. With 100 per cent efficiency, the , expansion would occur along isentropic line ob. Actually, however, most nozzles are only about 90 per cent efficient, the real expansion being along the line obi. Since the exact path of the line abt is not known, the work area is normally assumed by using the isentropic giving a work area abgea. The velocity at the mouth of the nozzle may be determined in the usual manner using this area and the velocity coefficient of the nozzle. At the evaporator pressure or slightly below, the vapor from the nozzle mixes with virtually dry saturated vapor from the evaporator. An impact loss also occurs at this point due to the mixture of vapors at different velocities. This results in bringing the state point of the mixture to c. Compression then occurs along the line cd, the work of compression per pound being cdfgc. In computing the work area, however, the point c is not actually known. Therefore, the work area cxdfgc\ is used in express ing the efficiency of the ejector, the line C\d being an isentropic. The losses are expressed by nozzle efficiency, impact loss and diffuser efficiency. The work of compression, however, is performed on the mass of the mixture. Thus, the available work is reduced in proportion to: - M primary mixture The impact loss is commonly determined from the formula: At ^primary 4" M ^secondary -- H ^mixture (8) Common efficiencies for commercial ejectors are: nozzle efficiency 90 per cent, diffuser efficiency 60 to 70 per cent. Customary steam rates in pounds per ton are approximately as follows: Evaporator temp, 50 F Steam press.100 lb per square inch Condenser temp. 105 F Steam rate30 lb per hour per ton Evaporator temp. 40 F Steam press.100 lb per square inch Condenser temp. 105 F Steam rate40 lb per hour per ton Steam .press. 12 lb per square inch Steam rate 45 lb per hour per ton Steam press. 12 lb per square inch Steam rate 70 lb per hour per ton CENTRIFUGAL VAPOR VACUUM SYSTEMS The centrifugal vapor vacuum system functions on the same general principle as the steam jet system, except that a centrifugal evacuator is used to produce the low absolute pressure instead of the velocity of the steam through a jet. Less condenser water is required and a vacuum pump is employed instead of a steam jet purge. CHARACTERISTICS OF COMPRESSION SYSTEMS The different types of compression systems have quite different characteristics of capacity and power with varying evaporator tempera ture and with varying condenser temperature, as will be seen from curves in Figs. 6 and 7. ,. The capacity of the reciprocating and rotary compressor varies slowly with a change of evaporator temperature, and the variance of power 439 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 requirements, in the air conditioning range of operation, is small for. a change of evaporator temperature. On the other hand, the capacity and power of the centrifugal machine vary rapidly, and the capacity of the steam ejector also varies considerably. Thus, both these latter types tend to be more nearly self-regulating than the reciprocating and rotary com pression type. On the other hand, the operating range of the latter near standard capacity is superior. Although the capacity of the reciprocating and rotary compressor is little affected by the condenser temperature, the power of the compressor is greatly affected, while the reverse is true CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS densing water is rather high in temperature. From Fig. 6 it is evident that steam jet refrigeration is better suited for use with evaporator temperatures above rather than below 40 F. CONDENSERS Condensers used in connection with refrigerating equipment for ab sorbing the work of compression are of three general designs: (1) air, (2) water, and (3) evaporative. Air Cooled Air cooled condensers are seldom used for capacities above 3 tons of refrigeration, unless an adequate water supply is extremely difficult to ' Fig. 6. Performance Characteristics of Compression Refrigeration Machines at Constant Speed for the centrifugal compressor. As previously indicated, the condenser temperature has no effect on the capacity of the steam ejector type of compressor until a certain point is reached, beyond which the capacity is zero. The steam consumption for the performance characteristic curves shown in Figs. 6 and 7 remains constant for all evaporator and condenser temperatures. Steam jet refrigeration requires from 3 to 10 times as much condenser water- as-other types of mechanical refrigeration, but its capacity is not effected by condensing water temperature as long as the water does not greatly exceed 100 F. Consequently, steam jet systems are well suited to-those applications where condensing water is cheap, or where con 440 Fig. 7. Performance Characteristics of Compression Refrigeration Machines at Constant Speed obtain, as for instance in railway air conditioning. Even on fractional tonnage installations, air is used as the condensing medium only where, water is expensive or where simplicity of-installation warrants the higher condensing pressure, and consequent higher power costs than can be obtained using water as the condensing medium. The conventional air cooled condenser consists of an extended surface coil across which air is blown by a fan. The hot refrigerant gas enters the- coil at the top and as it is condensed flows to a receiver located below the condenser. Air cooled condensers should always be located in a well ventilated space so that the heated air may escape and be replaced by cooler air. ` 441 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 The principal disadvantages of air cooled condensers are the power required to move the air and the reduction of capacity on hot days. This loss of capacity due to high condensing pressures on warm days requires that equipment of increased capacity be selected to meet the peak load. Thus, at normal loads the equipment is oversized. Water Cooled ^ Water cooled condensers are usually of the double pipe type or the shell and tube type. Double pipe condensers are arranged so that water passes through the inner of two concentric pipes, and refrigeration circulates through the annular space in the outer pipe. Where possible, there should be counter-flow of the refrigerant and the condensing water to maintain , maximum temperature differences. The amount and temperature of the condensing water determine the condensing temperature and pressure, and indirectly the power required for compression. It is, therefore, necessary to determine a balance so that the quantity of water insures economical compressor operation. Because there is a decided tendency to conserve the water in city mains and because most large cities are restricting the use of water for air conditioning and refrigeration equipment, it is often necessary to install cooling towers or evaporative condensers. Cooling towers, unfortunately, produce the warmest condensing water at the time when the load on the system is greatest, so that the refrigeration equipment must be designed to meet not only the maximum load at normal conditions, but also the maximum load at abnormal condensing water temperatures. If properly designed, this makes little difference in the efficiency of operation through out the year except at those times when the condensing water temperature is highest. As this occurs only for 5 per cent of the entire cooling period it can be disregarded as a factor in establishing yearly operating costs. The cooling tower has a certain advantage over the use of water from the city mains in that the temperature of the condensing water varies directly with the outdoor temperature and, as pointed out, the refrigera tion load also varies with this temperature. Certain economies are pos sible when a cooling tower is used which cannot be achieved by the use of condensing water from city mains, even where the city water temperature is extremely low. Normally, the lowest city water temperature met during the summer months is from 65 to 70 F. This temperature range takes place for the entire cooling period, regardless of the outdoor tempera tures. With the cooling tower, the temperature of the condensing water may rise to 80 or 85 F under maximum conditions, but under less than maximum conditions the temperature of the water leaving the cooling tower drops considerably, and it has been established that 50 per cent of the time the outdoor wet-bulb temperature varies from 60 to 70 F and the cooling tower water, for the same periods, varies from 65 to 75 F. When the outdoor wet-bulb temperature drops below 60 F, which occurs approximately 30 per cent of the time, the condensing water temperature is still lower. The cost of water used for condensing is negligible, as the only water required is that used to make up the loss by evaporation in the cooling tower itself. Refer to the section on cooling towers in Chapter 26. 442 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS Evaporative Due to the high cost of city water for condenser purposes and due to ordinances in some localities prohibiting the discharge of large quantities of such water into the sewage systems, there has been developed a con denser which uses a minimum amount of water on a finned surface, cooling it to approximately the wet-bulb temperature of the surrounding atmosphere. A diagram of a typical small evaporative condenser is shown in Fig. 8 which includes a fan that forces the air over a finned tube condenser coil to the outside atmosphere through a connecting duct. A fine spray of water keeps the coil surface wetted. The hot refrigerant gases enter the top of the condenser coil and the liquid collects in the receiver below Fig. 8. Diagram of Evaporative Condenser the condenser unit. A thermostatic control valve and pressure regulator are arranged on the condenser water supply for regulating and adjusting the water flow to the nozzle. It is desirable that a condenser of this type be located near the compressor. Units of this design are available in sizes ranging from 2 tons of re frigeration up t:o about 6 tons. About 10 per cent as much water is required for this unit as is normally used in a shell and tube type con denser. For larger capacities evaporative condensers are usually equip ped with a pump for recirculating the water. Such units are available in capacities ranging from 5 to 40 tons of refrigeration. They require no more water than a cooling tower, i.e., from 3 to 5 per cent as much water as required where all water is taken from the city main. EVAPORATORS AND COOLERS The types of coolers used in connection with air conditioning work fall into three general groups. The first, is the direct cooling of water; the second, direct cooling of air; and the third, cooling of brine for circulation in a closed system, which can cool either water or air. One method of the direct cooling of water is to install direct expansion coils in the spray chamber so that the water sprayed into the air comes in direct contact 443 < HEATING VENTILATING AIR CONDITIONING GUIDE 1940 with the cooling coils. Another common and efficient method of cooling spray water is to use a Baudelot type of heat absorber where the water flows over direct expansion coils at a rate sufficiently high to give efficient heat transfer from water to refrigerant. Another type of spray water cooler is the shell and tube heat exchanger in which the refrigerant is expanded into a shell enclosing the tubes through which the water flows. The velocity of the water in the tubes affects the rate of heat transfer, and as the refrigerant is in the shell com pletely surrounding the tubes at all times, good contact and a high rate of heat transfer are insured. The disadvantage of such a system is that with the falling off of load on the compressor the suction temperature or the temperature in the evaporator drops and there is a possibility of freezing the water in the tubes, which, of course, might split the tubes and allow the refrigerant to escape into the water passage. This danger can be eliminated by automatic safety devices. Another system of cooling spray water is to submerge coils in the spray collecting tank, or in a separate tank used for storage. The heat trans mission through the walls of the coils, however, is low and a great deal more surface is required than for any other type of cooler. However, with large storage tanks this type of cooling can be utilized to advantage. When direct cooling of air is employed, the refrigerant is inside the coil and the air passes over it. Cooling depends upon convection and con duction for removing the heat from the air. The type of coil used can be either smooth or finned, the finned coil being more economical in space requirement than the smooth coil. The fins, however, must be far enough apart so as not to retain the moisture which condenses out of the air. The indirect cooler, where brine is cooled by the refrigerant and the resulting cold brine is used to cool either air or water, introduces several other considerations. It is not the most economical from a power con sumption-standpoint, as it is necessary to cool the brine to a temperature sufficiently low so that there is an appreciable difference between the average brine temperature and that of the substance being cooled. This requires that the temperature of the refrigerant must be still lower, and consequently the amount of power required to produce a given amount of refrigeration increases due to the higher compression ratio. There are other considerations which make such a system desirable. In the first place, where a toxic refrigerant is undesirable or cannot be used because of fire or other risks, especially in densely populated areas, the brine can be cooled in an isolated room or building and can then be circulated through the air conditioning equipment. This arrangement eliminates any possibility of direct contact between the air and refrigerant. , REFRIGERANT PIPE SIZES The selection of proper pipe sizes and frictional pressure losses varies with the installation and the capacity of the system. Generally the suction piping should be selected so that the pressure loss is between 2 and 3 lb per square inch. The pressure drop in liquid lines should be maintained so as to permit no vaporization in the pipes with. limiting pressure drops not to exceed 5 lb per square inch. Hot or discharge gas 444 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS lines should be limited to approximately 4 lb per square inch pressure drop. All pressure drops mentioned are total system losses and include not only the piping losses, but also the pressure losses in the valves, fittings and coils. Pressure drops for discharge or hot gas lines may be determined from Table 1. Pressure losses in liquid refrigerant lines of various sizes and capacities are given in Table 2. Pressure drops of suction refrigerant pipe lines at varying capacities and refrigerant temperatures are given in Table 3. All tables are for 100 ft of pipe, including an average number of fittings, and for other lengths the losses are proportionate. Losses through control and regulating valves must be added to the other pipe losses to determine the total drop. All copper pipe referred to in these tables are of type L wall thickness and are designated by outside diameter. OPERATING METHODS There are various methods of designing and operating air condition ing systems to obtain economical . results. Peak outside conditions seldom exist for periods of greater than 3 hr. On many installations there is a peak internal load which may or may not coincide with the peak outside conditions. Thus, each application must be carefully analyzed by the engineer, and the proper equipment installed to satisfy the requirements. Adequate automatic controls should be installed for any system selected. Where there are a number of small rooms to be conditioned, as for example, a group of hotel bedrooms where the load varies with occupancy and exposure, it may be best to employ individual room units, each with its own control. These individual units may be of the self-contained type (condensing unit, evaporator, fan and controls all in one cabinet) or of the remote type with the condensing units located outside of the room. In some cases it is good practice to use one large condensing unit to serve a group of room evaporator units. Where this is done, the condensing unit must have some type of control which will prevent freezing evaporator temperatures when only a portion of the evaporators are in use. This can be accomplished by means of a back pressure regu lating valve which maintains the evaporator pressure at-a safe limit, but allows the crank case pressure to fall. Other methods of accomplish ing the same result are the use of a variable speed compressor or the use of a partial by-pass from the high side to the low side of the compressor. Any of these three methods of lowering the condensing unit capacity drop the operating cost at the reduced loads, but the operating cost per ton is higher. . Central Distribution Systems On air conditioning systems using duct distribution, the same general types of control are employed to meet the varying load conditions, i.e. (1) the system may consist of several condensing units and evaporators which are cut in or out, depending upon the demand, or (2) condensing unit capacity may be reduced by using back pressure regulating valves, by-pass valves, or variable speed compressors. 445 < HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Table 1. Pressure Losses in Dichlorodifluoromethane Discharge or Hot Gas Lines3 Capacity BTU per Hour 10,000 15,000 20,000 25,000 30,000 40,000 50,000 60,000 70,000 ' 80,000 90,000 100,000 125,000 150,000 175,000 200,000 250,000 . 300,000 400,000 500,000 600,000 800,000 1,000,000 1,250,000 1,500,000 2,000,000 Pressure Drop in Pounds per Square Inch per 100 Fib Line Sizes, Inches K K K m m IK 2K 2H 3H m 2.3 1.0 0.6 4.9 2.0 1.0 8.5 3.4 1.7 0.6 5.3 2.6 7.5 3.6 6.4 0.9 1.2 0.5 2.1 0.7 9.8 3.1 1.0 0.5 4.4 1.3 0.7 6.0 1.9 0.9 8.0 2.5 1.1 10.2 3.1 1.4 3.8 1.7 0.5 6.0 2.6 0.7 8.5 3.8 1.0 11.6 5.1 1.3 6.7 10.4 1.7 0.6 2.6 0.9 3.7 1.2 0.5 6.7 2.2 0.9 10.5 3.5 1.5 5.0 2.1 0.7 1.0 9.0 '" -- 3.8 5.8 9.5 1.8 2.9 4.4 6.4 11.3 aSoft annealed copper tubing up to and including outside diameter and larger. in. outside diameter. Hard copper pipe J4 in. bLength of tubing includes the average number of fittings. Another method of providing for economy of operation is to have storage capacity which can be utilized during the peak period. The refrigerating system can be operated for a longer period at maximum efficiency with tanks to store cold water or brine for supplementing the actual output of the refrigerating equipment. However, storage tanks require space and extra apparatus, which increase the cost of the entire system, and further, it is difficult to determine the exact size of the compressor because of the other variables which enter the problem. Depending upon the availability of storage space, the compressor may be designed for any reasonable percentage of the maximum load. On this basis of selection, the smaller the compressor, the larger the .storage space, and vice versa. 446 ii | f*7 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS " "' Table 2. Pressure Losses in Dichlorodifluoromethane Liquid Refrigerant Lines Capacitt BTU per Hour 100,000 125", 000 . 150,000 175,000 200,000 225,000 250,000 275,000 300,000 325,000 350,000 375,000 400,000 450,000 500,000 550,000 600,000 700,000 800,000 900,000 1,000,000 1,200,000 1,400,000 . 1,600,000 1,800,000 2,000,000 2,200,000 Pressure Drop in Pounds per Square Inch per 100 Ft* Pipe Rura, Inches K m IK iK 0.6 0.9 1.3 1.8 2.3 0.6 2.9 0.8 3.6 1.0 4.3 1.2 5.1 1.4 5.9 1.6 6.9 1.8 7.9 2.1 9.0 2.3 0.8 2.9 1.0 3.5 1.3 4.3 1.5 0.7 5.0 1.8 0.8 6.7 2.4 1.1 8.7 3.1 1.4 3.9 1.7 4.7 2.1 6.7 3.0 9.0 4.0 5.1 6.3 7.9 9.2 *Length of tubing includes the average number of fittings. s There is a further method of controlling the compressor output which is particularly adaptable to the centrifugal type of machine. This is accomplished by varying the amount of condensing water used with the fluctuation in load demand. Because of the characteristics of the cen trifugal type of apparatus, as the condensing water quantity is reduced and the condensing temperature consequently raised, the discharge pressure of the centrifugal machine rises correspondingly and the horse power input to the machine drops proportionately. While this reduces the total power input to the machine, it does not necessarily reduce the power input per ton of refrigeration developed, as the power input does not drop with a rising discharge pressure as fast as the refrigerating effect is reduced. 447 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 ( Table 3. Pressure Losses in Dichlorodifluoromethane Suction Refrigerant Lines ' " ' 100 Pressure Drop in Pounds per Square Inch per Ft Copper Pipe . .Actual O D Inches . Capacity BTU pee Hour -10 Refrigerant Temperature Deg F 0 10 ; 20 ' 3Q 40 50 2,000 4,000 6,000 0.3 0.3 0.2 0.2 0.2 0.1. 0.1 1.3 1.0 0.8 0.7 . 0.6 0.5 0.4 2.8 2.2 1.8: 1.5 1.2 1.0 0.9 8,000 4.8 3.8 3.1 2.6 2.1 1.8 1.5 10,000 7.4 5.8 4.8 3.9 3.3 2.8 2.3 y* 12,000 10.5 8.4 6.8 5.6 4.7 4.0 3.3 14,000 14.0 11.0 9.1 7.6 6.4 5.4 4.5 16,000 14.5 12.0 9.8 8.3 7.0 5.8 18,000 15.0 12.3 10.4 8.7 7.2 20,000 ! 15.0 12.7 10.7 8.9 7,000 10,000 15,000 0.4 0.3 0.3 0.2 0.2 0.2 0.1 1.0 0.7- 0.5 0.5 0.4 0.3 0.3 1.9 1.5 1.2 1.0 0.8 0.7 0.6 20,000 .25,000 35,000 3.3 2.6 2.1 1.7 1.4 1.2 . . 1.0 5.0 4.0 3.2 2.7 2.2 1.9 1.6 9.7 7.7 6.2 5.1 4.3 3.6 3.0 45,000 60,000 70,000 15.8 12.6 10.0 8.4 14.8 7.0 12.2 5.9 10.2 14.0 4.9 8.6 11.7 10,000 15,000 20,000 0.3 0.2 0.2 0.2 0.1 0.1 0.1 0.7 0.5 0.4 0.3 0.3 0.2 0.2 1.2 0.9 0.7 0.6 0.5 0.4 0.4 30,000 40,000 50,000 2.6 2.1 1.6 1.3 l.i 0.9 - 0.8 4.6 3.6 2.8 2.3 1.9 1.6 1.4 7.0 5.5 4.4 3.5 2.9 2.5 2.1 60,000 10.0 7.8 6.2 5.0 4.2 3.5 3.0 80,000 14.0 11.0 8.7 7.3 6.2 5.2 100,000 13.5 11.3 9.5 8.2 30,000 40,000 50,000 1.6 1.3 1.0 0.8 0.7 0.6 0.5 2.7 2.1 1.7 1.4 1.1 0.9 0.8 4.2 3.2 2.5 2.1 1.7 1.4 1.2 60,000 6.1 4.5 3.6 2.9 2.4 2.0 1.7 m 70,000. 8.7 6.3 4.8 3.8 3.1 2.6 2.2 80,000 8.4 6.3 4.9 4.0 3.3 2.8 90,000 100,000 120,000 8.0 6.2 4.9 4.1 3.5 10.0 7.6 6.1 5.0 4.2 8.6 7.0 5.9 140,000 9.5 7.9 Length of tubing includes the average number of fittings. 448 CHAPTER 24. COOLING AND DEHUMIDIFICATION METHODS Table 3. Pressure Losses in Dichlorodifluoromethane Suction Refrigerant Lines (Continued) Copper Pipe Actual O.D. Inches Capacity BTU per Hour Pressure Drop in Pounds per Square Inch PER 100 Ft Refrigerant Temperature Deg F -10 0 10 20 30 40 50 50,000 100,000 150,000 0.7 0.5 0.4 0.3 0.3 0.2 0.2 2.6 1.8 1.4 1.1 0.9 0.8 0.7 5.6 3.9 3.0 2.4 2.0 1.6 1.4 200,000 9.8 6.7 5.2 4.1 3.4 2.8 2.4 2 'A 250,000 14.8 10.3 8.0 6.3 5.1 4.2 3.6 300,000 14.5 11.3 9.0 7.2 6.0 5.0 350,000 400,000 19.5 15.3 19.6 12.0 15.3 9:7 1215 7.8 10.0 6.7 8.5 50,000 0.2 0.2 0.1 0.1 0.1 0.1 0.1 100,000 0.7 0.6 0.5 0.4 0.3 0.2 0.2 150,000 : 1.6 1.2 1.0 0.8 0.6: 0.5 0.4 200,000 250,000 300,000 2.8 2.1 1.7 1.4 1.1 0.9 0.7 4.3 3.4 2.6 2.1 1.7 1.3 1.1 6.1 4.5 3.7 3.0 2.4 1.9 1.5 m 350,000 8.2 6.0 5.0 4.0 3.2 2.5 2.0 400,000 7.8 6.5 5.1 4.2 3.3 2.7 450,000 - 7.7 6.4 5.3 4.0 :3.5 . 500,000 550,000 600,000 7.8 6.4 5:0 4,2 7.7 6.2 5.1 7.4 6.2 200,000 300,000 400,000 1.2 1.0 0.8 0.6 0.5 0.4 0.4 2.6 2.0 1.6 1.3 1.0 0.8 0.7 .4,5 3.4 2.6 . 2.1 1.7 1.4 1.3 500,000 7.3 5.4 4.1 3.3 2.7 2.2 .1.9 iVa 600,000 8.1 6.0 4.7 3.8 . 3.1 2.7 ' 700,000 8.4 6.5 5.2 4.2 3.5 800,000 900,000 1,000,000 8.6 6.8 8.7 5.5 4.6 7.0 ,. ... 5.9 8.9 7.3 300,000 400,000 500,000 1.2 0.9 0.7 0.6 i 0.5 i 0.4 0.3 2.0 1.6 1.3 1.0 .0.8 . : 0.7 0.6 3.2 2.5 1.9 1.6 1.3 1.0 0.9 600,000 4.6 3.6 2.8 2.2 1.8 1.5: 1.3 700,000 6.4 4.9 3.8 3.0 2.5 : 2.0 1.7 3Va 800,000 8.7 6.4 4.9 3.9 3.2 2.5;1 2.2 900,000 8.2 6.2 4.9 3.9 3.2 ' 2.7 1,000,000 7.7 6.1 4.9 4,0 3.3 1,100,000 9.4 7.3 5.8 4.8 ! 4.0 1,200.000 1,300,000 1,400,000 8.7 6.9 5.6 4.8 8.0 6.6 5.6 9.3 7.6 6.4 Length of tubing includes the average number of fittings.:. 449 HEATINC VENTILATING AIR CONDITIONING GUIDE .1940 Table 3. Pressure Losses in Dichlorodifluoromethane crT<~rTr>N Refrigerant Lines (Concluded) Copper Pip &.CTUAL 0.0. Inches Capacity BTU per Hour 400.000 600.000 800,000 1,000,000 1,200,000 4ys 1,400,000 1,600,000 1,800,000 2,000,000 2,200,000 Pressure Drop if Pounds per Square Inch per 100 Fr> -10. 1.0 2.4 4.1 6.6 10.0 Refrigerant Temperature Deg V 0 0.8 1.8 3.1 4.8 7.1 10.0 10 0.6 1.4 2.4 3.7 5.4 7.5 10.0 20 0.4 1.1 2.0 3.0 4.4 5.9 7.7 10.0 30 0.4 0.9 1.6 2.5 3.5 4.8 6.2 7.9 9.7 40 0.3 0.7 1.3 2.0 2.9 3.9 5.1 6.4 7.9 9.5 50 0.3 0.6 1.1 1.6 2.4 3.3 4.2 5.3 6.6 7.9 Length Of tubing includes the average number of fittings. ADSORPTION SYSTEMS A diagrammatic representation of an open solid material adsorption system is shown in Fig. 9. Two or more beds of the adsorbent are used so that one bed may be used as an adsorber while another is being re activated. Most adsorption systems use some internal means of heating the adsorbent bed before activation, and cooling it after activation. Thus, the use of relatively high room temperatures and comparatively large amounts of outside air are desirable in connection with' these systems. In order to offset the effect of high air temperature, some effort is made to keep the humidity lower than usual. ' 450 W"3> CHAPTER 24. COOLING AND DEHUMIDIEICATION METHODS Silica Cel ' Either of two arrangements may be used in systems employing silica gel in place of refrigeration. In the one principally used, the air from which moisture is to be extracted is taken through silica gel beds by suction or pressure fans. The moisture is adsorbed by the silica gel and the air leaves at a lower dew-point and a higher dry-bulb temperature than those at which it entered. If this air is passed over surface coolers in which tap water or another cooling medium is flowing through tubes, a certain amount of sensible heat will be removed. The air leaves the surface cooler or interchanger with the same dew-point with which it emerged from the silica gel beds, but with a lower dry-bulb temperature, although the dry-bulb temperature may be higher than the temperature of the air entering the silica gel beds. In the other arrangement, the first two of the steps outlined are dupli cated, and in addition the air is carried through a spray type washer. Because the air enters the washer with a low wet-bulb, and because adiabatic saturation will take place at a temperature close to the entering wet-bulb considerable cooling of the air can be accomplished; but this can be done only with a consequent increase of the dew-point. It is necessary to reactivate the silica gel after it has adsorbed about 25 per cent of its own weight in the form of moisture. As reactivation requires a high temperature and since silica gel is only active at low tem peratures, cooling of the beds must also be completed before they can be used again. This necessitates three stages in the silica gel containers and requires either three beds of silica gel or one bed divided and automatically put in- position. The reactivation is usually done by means of gas or oil fires and the cooling of the beds by means of indirect water cooling or by means of small quantities of dehydrated air taken from the system beyond the interchanger. Activated Alumina The application is quite similar to that employed for silica gel; that is, the material is exposed to the air flow and after reaching about 75 per cent saturation is reactivated by removing the moisture adsorbed by means of applied heat. The actual' scheme generally followed in the use of this material for continuous service varies somewhat from silica gel inasmuch as the material is placed in three units which are used consecutively for the different steps. These steps permit each unit to operate as follows: (1) in series with the preceding unit, (2) alone, and (3)in series with the following unit. This plan allows for adsorption, reactivation, and cooling, in a manner similar to that used with silica gel. The alumina in a single unit, when it is in the first step and operating with the preceding unit, adsorbs approximately 25 per cent of the moisture removed from the air and takes up about 1.3 per cent of its weight of water. During the second step when it is operating alone, it ' takes up 100 per cent of the moisture removed from the air until the weight of the water adsorbed is brought up to about 6.7 per cent. During the third step when the unit is operating with the succeeding unit, it extracts about 75 per cent of the moisture removed from the air until the water weight adsorbed comes up to about 10 per cent of the weight of the 451 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 adsorber. The time allowable for reactivating is equal to the time occu pied by the second unit adsorbing alone, plus the time when the second and third units are adsorbing in series, plus the time when the third unit is adsorbing alone, at the expiration of which time the first unit will be again required. The temperature of air used for alumina reactivation is usually between 300 and 700 F and the air flow rate will have to be higher with the low temperature air than it will be with reactivating air of higher temperature. For example, air at 400 F for reactivating will, at 10 cu ft per hour per pound of alumina, require about 6 hr for reactivation. In the three unit system, after reactivation the cooling of the activated alumina may be carried out with considerable rapidity by using dry air from the adsorp tion unit for circulation through the unit which has just completed reacti- Conditioned air Dry bulb dependent upon cooling medium ` 58D. P. Fig. 10. Diagram of Lithium. Chloride Absorption System vation. The final temperature of the unit before it goes back into service should be not over 200 F. As a basis for computing the amount of cooling air required for reactivation, each cubic foot of cooling air has been found capable of removing 2.2 Btu when heated from 85 to 200 F and of provid ing a sufficient margin of safety in operation. . .. OPEN ABSORPTION SYSTEMS The cycle of liquid absorbents are fundamentally the same. A diagram of a lithium chloride absorption system is shown in Fig. 10. The liquid absorbent is brought in contact with air having a certain vapor pressure due to its contained water vapor. The absorbent, having a lower vapor pressure,- absorbs moisture in the form of water from the water vapor that is in the contacting air. A change of state takes place because there is a rise in temperature in the liquid absorbing the moisture, which is a function of the amount of water vapor condensed from the air stream. 452 CHAPTER 24. COOUNC AND DEHUMIDIFICATION METHODS Absorption of moisture by the liquid weakens the: concentration of the liquid so that its absorbing capacity is reduced and regeneration, or the driving off of the excess moisture in the liquid, must be performed. A constant density can be maintained by continuously withdrawing a small portion of the total liquid for intensive concentration without varying the vapor pressure of the total mass. ' There are two methods of regeneration. One is to boil off the excess moisture by raising the temperature of the solution above the boiling point of the particular concentration. As the salt in the solution does not vaporize, it is not carried off in the boiling process: In the small amounts of liquid diverted to the regenerator for concentration, care should be taken that too much moisture is not driven off, which may cause freezing or solidification of the salts. The second method of regeneration is to raise the temperature of the solution with ordinary steam coil interchangers to about 225 F, and then passing the solution at this temperature over various types of scrubbers, through which untreated air is circulated. The increase in temperature of the liquid raises its vapor pressure to such an extent that there is an exchange of vapor between the liquid and the air, as well as an equali- . zation of temperature between the air and the liquid absorbent. The air is then capable of taking up part of the moisture from the liquid and carries this excess moisture into the atmosphere with the leaving air. After this vaporization has taken place, the highly concentrated, hot brine is circulated through an interchanger through which the water used in cooling the main solution can be re-used to reduce the temperature of the concentrated solution to a point where it may be introduced into the main solution tank at only a slightly higher temperature than the main body of the solution.' There are two places in the operation where there is a tendency to raise the temperature of the liquid. One is the absorption of vapor from the air, which changes the latent heat of the vapor absorbed to sensible heat, thus raising the temperature of the liquid and consequently, the temperature of the air. The other is the heat added to the regenerator liquid in order to re-evaporate and carry off the excess moisture which has been condensed in the first stage. This type of system is not limited to lithium chloride, as calcium, zinc or barium chloride and various combinations of halogen salts may also be used.. . CLOSED ABSORPTION SYSTEMS The fundamental rule governing the absorption (in a. closed system) of a gas by a liquid is Raoult's Law, which states that at.any given temp erature the ratio of the partial pressure of a volatile component in a solution to the vapor pressure of the pure component at the same temp-.' erature is equal to its mol fraction in the solution. The mol fraction, in turn, is equal to the number of mols of substance divided by the total number of mols present. The number of mols in a given weight of a compound is equal to the weight divided by the molecular weight. This law applies strictly, only to what is known as an ideal solution, that is, one in which the intermolecular forces between the substances 453 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 present in the solution are equal. Actually, no such solutions exist, so that deviations from Raoult's Law are always found in practice. The deviation is called positive when the observed pressure is greater than that calculated from Raoult's Law, while the term negative deviation refers to the opposite case. Negative deviations are found wherever chemical attraction exists between the solvent and the solute. Positive deviation occurs when there is a difference in the internal pressure of the com ponents, chemical attraction between them being absent. In order to make an effective absorption machine, large negative deviations from Raoult's Law must be shown by solutions of the refrig erant in the liquid absorbent, because, the larger the negative devia tion, the greater is the amount of refrigerant that can be cycled, using a given weight of absorbent. Cycling a large amount of refrigerant for a given weight of absorbent is important because of the heat required to raise the temperature of the mixture and disassociate the refrigerant Fig. 11. Closed Absorption System and the absorbent. Only the latent heat of the refrigerant can be recovered for useful work. . Many refrigerant-absorbent combinations have been proposed and quite a number have been tested. Fig. 11 is a diagrammatic representation of a typical closed -absorption system. In this system a mixture of refrigerant and absorbent is evaporated in the generator, passes to an analyzer and rectifier where it is purified, and then to a condenser where the refrigerant and remaining absorbent is condensed. It then- passes through an expansion valve to an evaporator, where heat is absorbed from a cooling load. From the evaporator the vapor and residual ab sorbent passes to. an absorber where it meets absorbent which is ini tially low (weak) in refrigerant concentration. The absorbent absorbs the vapor, and the strong absorbent liquor is transferred to the generator through an interchanger with the weak liquor returning- from, the generator. . .' A cooling medium, ordinarily water, is used in the absorber to remove 454 .' CHAPTER 24. COOLING AND DEHUMIDIFICATION. METHODS the heat of absorption and maintain the absorptive power of the absorber at a maximum. Like the steam ejector system, the absorption system compares most favorably when a cheap source of cooling water and steam or other heat source is available. Unlike the ejector system, the comparative performance is usually best with a wide range of temperature between the evaporator and absorber, since with a good refrigerant-absorbent combination, the amount of heat and water required for a given refrig erating effect increases slowly with an increase of evaporator-condenser temperature range. At the present time the most used refrigerant-absorbent combinations are: (1) water and ammonia and' (2) monofluorodichloromethane and dimethyl ether of tetraethylene glycol. With the latter combination the boiling points of the refrigerant and absorbent are sufficiently wide apart that almost pure refrigerant is obtained without the use of a rectifier. EVAPORATIVE COOLING Evaporative cooling is accomplished by passing air through a water spray in which the water is being continually recirculated. The air, entering in an unsaturated condition, evaporates a part of the water at the. expense of the sensible heat. As this is an adiabatic transfer, the total heat content of the air remains constant, while the dew-point rises and the dry-bulb falls until the air is saturated. The reduction, in dry-bulb temperature is a direct function of the wet-bulb depression of the air entering the spray chamber and the re sulting air temperature is governed entirely by the entering wet-bulb temperature of the outside air and the efficiency of the spray. Evaporative cooling is being used advantageously in many parts of the country. By using all outside air in sufficient.volume to increase the air motion in an occupied space and to limit the temperature rise of the air to approximately 8 F an entering wet-bulb temperature as high as 70 F will result in effective evaporative cooling. THE REVERSE CYCLE The idea of heating by the reverse refrigeration cycle has captured the imagination of many people and has been much discussed. In principle, heat is absorbed in an evaporator from some available source of heat, pumped to a higher temperature and delivered to a condenser. The heat from the condenser is used for heating purposes. The compressor acts as a heat pump whose fundamental function is to raise the potential of the heat. The'theoretical work of compression in relation to the heat delivered is: ' , Ti - T, where ' Ti = absolute temperature of evaporator. . Tt -- absolute'temperature of condenser. .. W Thus, with a small spread of temperature between the evaporator and the condenser, 6 or 8 times as much heat may be obtained theoretically r HEATING VENTILATING AIR CONDITIONING CUIDE 1940 and 4 or 5 times practically, as the work put in. There are a number of limitations, however, the most serious of which is the lack of ready availability of a practical source of heat. 1. Well water is the most desirable since its temperature is high even in the winter and thus a large amount of heat may be removed in relation to the weight of water handled. 2. Air may be used but its specific heat is low and its temperature-uncertain. When the most heat is needed, the temperature of the air is lowest, thus resulting in the least favorable temperature combination. ' 3. It has been proposed to obtain heat by freezing water, but this is still in the theoretical stage. .. Some of the other factors which act as limitations are the large tem perature spread when using air as a source of heat and when attempting to cool with even moderately low outside temperatures, the. frequent disr parity between the size of the cooling load and heating load requiring extra equipment for a complete heating load, and the relatively high initial cost of equipment at present available for the reverse cycle in comparison with that available for heating by conventional means. . Because of these limitations, the present application of the system, is largely limited to temperate climates, such as Florida and Southern California, or to heating only for intermediate seasons, or to other locali ties which have peculiar advantages as, for instance', the ready availa bility of well water. In these locations it is frequently possible to do all of the heating necessary with the refrigeration equipment so that the extra cost is only that of reversing the functions of the condenser and evaporator. ICE SYSTEMS The use of ice for air conditioning is becoming more adaptable particu larly for the smaller commercial installations where first cost is paramount and where the operating period is limited to only a few hours per'day. Restaurants serving only one or two meals per day, tea rooms, meeting halls and other comparable installations have found ice to be advan tageous in comparison with other methods. Local ice manufacturers will furnish complete data for this type of system. Example 1. Electrically driven dichlorodifluoromethane condensing units are to be used in an air conditioning system, requiring 20 tons refrigerating capacity for conditions of maximum load. An overall analysis of the seasons operating conditions shows an average load factor of 62.5 per cent, and allowing for variable time intervals of operation of refrigeration units installed, three-quarters of the operating season, or 750 hr, would require operation of the equipment at one-half load, and one-quarter of the operating season or 250 hr full load capacity of the refrigeration equipment would be required. The increased first cost of 2-10 hp, 10 ton condensing units over 1-20 hp, 20 ton con densing unit is, $830.00 installed price;, to the customer. The increased first cost of a 2-speed compressor motor of 20 hp size over a constant speed of 20 hp size motor including increased starter cost is $210.00. The efficiency of the 2-speed motor above is 83 per cent at full load speed, and 79 per cent for full load at 14 speed. At \4 speed, full load is 14 total bhp of full load speed. Discuss the consideration involved in making, a decision as to whether a single unit with a 20 hp motor of the 2 speed type would be used in preference to 2-10 hp constant speed units. ' Solution. The cost of 2-10 hp 10 ton units in excess of 1-20 hp, 20 ton unit with 2-speed motor, is $830.00--$210.00 or $620.00, increased first cost. At 15 per cent fixed charges, 456 CHAPTER 24. COOLINC AND DEHUMIDIFICATION METHODS this represents an increased annual cost of $93.00 for 2 compressors over one compressor. The advantage of 2 compressors instead of one compressor on an installation of this type, is in the breakdown service provided in the event one compressor is shut down for repairs the system could be operated at one-half capacity utilizing the duplicate machine. The motor efficiency of the constant speed unit would be higher at full load than would be the efficiency of the 2-speed motor at low speed. Offsetting this latter advantage however, is the fact that the condenser on the condensing unit would provide a lower refrigerant condensing temperature for load operation with the same final condensing water temperature than would be the case with duplicate units each furnished with its own compressor and condenser. Operation, at a lower condensing temperature would provide for a power saving compensating for the lowerefficiency of the 2-speed motor when operated at slow speeds. It is, in a case" of this kind, purely a question as to whether or not the purchaser would deem an investment of $620.00 more and an increased fixed charge of $93.00 a year, advisable to get breakdown service through the installation of duplicate units. In most cases, this increased first cost would not be warranted because of the fact that satisfactory indoor conditions could not be obtained at full load if only one-half the refrigeration capacity were available. Example 8. For condensing purposes, an air conditioning system uses city water which has an average 70 F supply temperature. The following table lists the number of hours _per year during which definite wet-bulb temperatures and corresponding refrigeration rates pertain. Wet-Bulb FTemperature 80 79 - 75 74 - 70 69-65 64 - 60 59 - 55 54-50 No. or Hours per Year 6 100 277 330 277 158 52 Total 1200 hours ' ' Refrigeration Required Tons 284 233 183 157 144 79 37 If the power requirements of a dichlorodifluoromethane refrigeration system are in accordance with the following data on partial load operation, determine the seasonal power cost at 2 cents per kwhr: Tons of Refrigeration Kw per ton 284 233 183 157 144 79 37 0.89 0.89 0.87 0.86 0.86 0.93 0.97 Solution. Seasonal power cost: . . Wet Bulb FTemperature Ton-Hours - Kwhr 80 79 - 75 74 - 70 69 - 65 64 - 60 59 - 55 54 - 50 Totals 6 X 284 = 1,704 100 X 233 = 23,300 277 X 183 = 50,700 330 X 157 = 51,800 277 X 144 = 39,900 158 X 79 = 12,500 52 X 37 = 1,920 1,704 X 0.89 = 1,517 23,300 X 0.89 = 20,750 50,700 X 0.87 = 44,100 51,800 X 0.86 = 44,500 39,900 X 0.86 = 34,300 12,500 X 0.93 = 11,600 1,920 X 0.97 = 1,860 181,824 ton-hours 158,627 kwhr The 158,627 kwhr at 2 cents per kwhr will cost $3,173. The average consumption will be Jgj^lPtLn'hours = 0 873 kw per ton- 457 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Example S. Using the data from Example 2, if city water costs 20 cents per thousand gallons, and if 1.25 gal are used per minute per ton, estimate the annual water cost. Solution. 60 X 1.25 = 75 gal per ton-hour. 181,824 ton-hours X 75 = 13,620,000 gal per year. 13,62y ^20 => $2,724 the yearly cooling water cost. Example 4- Using the data of Example 2, if a cooling tower were installed for refusing the condensing water, estimate the annual compressor power cost of a dichlorodifluoromethane refrigeration system if the final temperatures of the water leaving the cooling tower and the kilowatt input per ton are the following:* 53 Tons Temperature of water leaving tower, F Kw input per ton 284 233 183 157 144 79 37 86.7 81.8 76.5 72.1 66.4 61.3 55.6 1.10 0.94 0.85 0.80 0.74 0.59 0.62 Solution. Wet-Bum FTemperature 80 79 - 75 74 70 69 - 65 64-60 59 - 55 54-50 Totals Kw per Ton 1,704 23,300 50,700 51,800 39,900 12,500 1,920 X X X X X X X 181,824 ton-hours 1.10 0.94 0.85 0.80 0.74 0.59 0.62 Kwhs = 1,875 =S 21,900 -- 43,300 -- 41,400 = 29,500 = 7,370 = 1,200 146,545 The 146,545 kwhr at 2 cents per kwhr will cost $2,931. 545 kwhr The.average consumption will be jgj 324 ton-hours = 0.805 kw per ton. Example 5. If a steam ejector system were used to secure the refrigeration for the air conditioning system of Example 2, compute the annual steam cost if steam is sold for 53 cents per thousand pounds and if there is an average steam consumption of 20 lb of steam per hour per ton when used with a cooling tower system. Solution. 181,824 tons X 20 lb of steam per ton = 3,636,480 lb of steam. The 3,636,480 lb at 53 cents per thousand pounds will cost $1,929. 458 Chapter 25 HEAT TRANSFER SURFACE COILS Coil Applications, Construction and Arrangement, Steam Coils, Water' Coils, Direct-Expansion Coils, Flow Arrange ments. Applications, Calculation of Heat Transfer, Air Flow Resistance, Coil Performance, Selection THE coils described in this chapter are used in air conditioning sys tems for heating or cooling an air stream under forced convection. The surface coil equipment may be made up of a number of banks assembled in the field, or the entire assembly may be factory constructed. The applications of each type of coil are limited to the field within which it is rated. Other limitations are imposed by code regulations, by proper choice of materials for the refrigerants used and the condition of the air handled, or by an economic analysis of the possible alternates on each installation. > For heating service, these coils are used as preheaters, reheaters or booster heaters, (see Chapters 21 and 22). The function of the coils is air heating only, but the apparatus assembly may include means for humidi fication and air cleaning. Steam or hot water are the usual heating media, although others are used in special cases, such as reheating by means of discharge gas from a refrigerating system. Coils are used for air cooling with or without accompanying dehumidi fication. Examples of cooling applications without dehumidification are precooling coils using well water or other relatively high temperature water to reduce the load on the refrigerating machinery, or water cooled coils to remove sensible heat in connection with chemical moistureabsorption apparatus. By proper coil selection it is possible to handle both sensible cooling and dehumidification together as further explained later. The apparatus assembly usually includes an air cleaning means to protect the coil from accumulation of dirt and to keep dust and foreign matter out of the conditioned space. Although cooling and dehumidi fication are the usual functions, there are cases of cooling coils purposely wetted as an aid to air cleaning and odor absorption. The usual cooling media used in surface coils are cold water and volatile refrigerants such as dichlorodifluoromethane and methyl chloride, but others are used in special cases. Brines are seldom required for the range of applications covered by this chapter, although there are cases where low entering air temperatures with large latent heat loads require a refrigerant temperature so low that water becomes impractical. Some- 459 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 times, also, brine from an industrial system already installed, is the only convenient source of refrigeration. For combined cooling and dehumidifying, surface coils present an alter nate to spray dehumidifiers. For many applications it is possible, by proper selection of apparatus, choice of air velocities, refrigerant tempera tures, etc., to perform the same duty with either. In a few cases both sprays and coils are used. The coils may then be installed within the spray chamber, either in series with the sprays or below them. In making the selection between spray and surface dehumidifiers, certain advantages of each should be considered. The fact that a spray dehumidifier is usually designed to deliver nearly saturated air, tends to simplify the control' problem. In this case the dry-bulb temperature is also the dew-point, and hence a dew-point control can be arranged by using a simple duct thermo stat. Spray dehumidifiers have the advantage over unwetted coils of a certain degree of air cleaning and odor absorption. On the other hand, coils make possible a closed and balanced cooling water circuit, obviating. the unbalanced pumping head, the complication of water level control, and danger from possible floods incidental to multiple-spray dehumidi fiers, especially if located on.different levels. The use of coils often makes it possible for the same surface to serve for summer cooling and winter heating by circulating cold water in the one season and hot water in- the other, with consequent saving in apparatus and piping. Surface-coil dehumidifiers seldom deliver saturated air, and wet-bulb depression of 0.5 to 4 F (or more) is usual. Another advantage is that where the surface coil system can be used with direct expansion of refrigerant, it is com paratively low in initial and operating costs. Of course the safety of the occupant must be kept in mind in comfort conditioning applications. Some localities have refrigeration codes which restrict the use of direct-ex pansion coils in the air stream, and hence local codes should be consulted by the engineer before a system employing direct expansion methods is designed. The choice between spray dehumidifiers and coils depends upon the necessities and the economic aspects of each case and no general rule can be given. There are many installations in which either can be used. COIL CONSTRUCTION AND ARRANGEMENT Coils are basically of two types, those consisting of bare tubes or pipe and those of extended surface construction. The former are little used for the applications covered by this chapter, but are often employed where conditions cause frost accumulation, and for cooling surface within spray dehumidifiers. The heat transmission from air passing over a tube to a refrigerant flowing within it, is impeded by three resistances. The same is true when the air is being heated by steam or hot water in the tube. The first resistance is from the air to the surface of the tube, usually called the outside surface resistance or air-film resistance. Second is the resistance to the flow of heat by conduction through the metal itself. Finally there is another surface or film resistance to the flow of heat between the inside surface of the metal and the fluid in the tube. For the applications under consideration both the resistance of the metal wall to heat conduction, and the inside surface or film resistance are usually low as compared with the air-side surface resistance. This is especially the case where sensible 460 CHAPTER 25. HEAT TRANSFER SURFACE COILS heating or cooling only is accomplished. Where dehumidification accom panies sensible cooling, or where the external surface of the tube is sprayed with large quantities of water, the resistance to heat flow between the tube and the air flowing over it is much decreased. In the case of the water spray, the surface resistance, depends on the amount and the method of application of the watfer. Economy in space, weight and cost make it advantageous to decrease the external surface resistance, where it is proportionately large, to approach that of the tube wall,-and that from tube to refrigerant. This is accomplished by increasing the external surface by means of fins. With water spray the external resistance is already low, and the fins are less useful for increasing the overall heat transfer. Sometimes water spray is applied to the same type surface as would have been used without it. The overall heat transfer is not neces sarily increased much by such an arrangement, but the water spray may serve other purposes than, to increase the flow of heat, such as air and coil cleaning. . In fin or extended surface coils the external surface of the tubes is known as primary and the fin surface is called secondary. The primary Spiral fins Flat corrugated fins 3' O O OO Flat continuous fins mmmm O O Flat square fins O O Fig. 1. Types of Fin Coil Arrangement surface consists generally of round tubes or pipes. In some cases these are staggered and in others in line with' respect to the air flow. The staggered arrangement gives a somewhat higher heat transfer value but also a higher resistance to air flow and in some cases makes the header and return bend arrangement more complicated. A number of types of fin arrangement are used, the most common of which are spiral, flat and flat-crinkled or corrugated, all as shown in Fig. 1. While the spiral fin surrounds each tube individually in all cases, the flat types may be con tinuous (including several rows of tubes), or they may be round or square, with individual fins for each tube.' All of these, as well as other less common types are in use, the selection for a particular installation being based on economic'considerations, space-requirements and resistances of individual designs of coils. A most important factor in the performance of extended surface coils is the bond between the fin. and the tube. An intimate contact is assured in a number of ways. The assembled coil may be coated with tin, zinc, etc., after fabrication. The spiral type fin may be knurled into a shallow groove .on the exterior of the tube. The tube may be expanded after the fins are assembled, or the tube hole flanges of a flat or corrugated: fin may be made to override those in. the preceding 461 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 fin and so compress them upon the tube. There are also types of con struction where the fin is formed out of the material of the tube itself. In any case the successful performance of a fin surface depends upon the bond between fin and tube being secure and remaining so in service. For heating coils the materials most generally used are copper, steel and aluminum. Sometimes aluminum or brass fins are used on copper tubes. Steel is uncommon except in special cases. Some types of heating coils are made of cast-iron. There are sufficient practical installations of each of these to demonstrate that they can all give good service. However for equal performances brass and aluminum fins must be of greater thickness than copper fins on account of their lower coefficients of conduction. The copper coils are frequently tin-dipped and steel coils galvanized to protect them from corrosion and to assure a bond between fin and tube. Cooling coils for water or for volatile refrigerants are most frequently of copper, both fin and tube. Aluminum fins on copper tubes are also used. For brines such as sodium or calcium chloride and for ammonia,., steel fins and tubes are common. - Although there are many variations for special cases, tube and fin sizes and spacings for air conditioning coils, both heating and cooling, fall within fairly narrow limits. The tubes are usually or 34 in. OD, and the fins spaced from 4 to 8 per inch, 6 per inch being a common design. The tube spacing generally varies from about to 2 in. on centers. Small tube size and close fin spacing give large capacity with small space demand, but the resistance, both over the surface and through the tubes, is higher than with larger tubes and more widely spaced fins. Moreover, too close a fin spacing may result in trouble from dirt accumu lation, especially on dehumidifying coils, and may also cause trouble from water hold-up between the fins, particularly with air flow vertically upward. This condition increases the air resistance and de creases the capacity;of the coil. Water hold-up sometimes causes flooding trouble in vertical air flow units by accumulating too much water for the drain to handle all at once when the fan is stopped. Steam Coils For proper performance of steam heating coils, condensate and air must be continually eliminated and the steam must be evenly distributed to the individual tubes. This distribution is usually accomplished by individual orifices in the tubes, by distributing plates and orifice in the steam header, or by perforated internal steam-distributing pipes extending into the individual tubes. The latter arrangement has the advantage of distributing the steam throughout the length of each tube,, and is con ducive to uniform delivered air temperatures. The tendency for freezing of condensate at the bottom of the coil with cold entering air and light heating loads is also minimized. This is especially valuable for outside air preheaters. Methods of air and condensate elimination are discussed in detail in Chapters 15, 16 and 22. Water Coils The performance of water coils, for heating or cooling, depends on the elimination of air from the system and proper distribution of water. Air elimination is taken care of in the system piping as described in Chapter 462 . CHAPTER 25. HEAT TRANSFER SURFACE COILS 17. To assure a pressure drop sufficient for adequate distribution but at the same time to provide against excessive pumping head where large water quantities are handled, water coils are provided with various water circuit arrangements. For instance, a typical coil 18 tubes high and 6 tubes deep in the direction of air flow can be arranged for 6, 9, 18 or 36 parallel water circuits as conditions may require. Orifices in individual tubes are occasionally employed but are usually unnecessary as the resistance of individual water circuits is generally sufficient to effect a satisfactory distribution. In cases such as well water precooling coils, where there may be considerable sand and other foreign matter in the water, provision for cleaning of individual tubes is of advantage. It is important to arrange water coils for drainage if located where they will be Fig. 2. Various Water Circuit Arrangements exposed to freezing. For this reason the circuits should be so laid out that there are no pockets to hold water. Fig. 2 shows such construction. The drains may be provided in the water piping although they are often arranged in the coil headers. ' Direct-Expansion Coils Coils for volatile refrigerants present more complex problems of fluid distribution than do water, brine or steam. It is desirable that the coil be effectively and uniformly cooled throughout, and necessary that the compressor be protected from entrained, unevaporated refrigerant, There are two types; namely, flooded systems, and thermal expansion valve systems, as shown in Figs. 3 and 4. With flooded control the coils are supplied with liquid by the same type of circulation that exists in a water tube boiler, while the level in the surge drum is maintained by the action 463 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 of the float regulator, or by properly charging the plant in the case of the high pressure float drainer. The thermal expansion valve system depends upon-the thermal valve automatically feeding just as much liquid to the coils as is required to maintain the superheat at the coil suction outlet within predetermined limits which vary from about 6 to 10 F. The Fig. 3. Direct-Expansion Coil with Flooded System Fig. 4 Direct-Expansion Coil with Thermal Valve System thermal valve arrangement is in common use for the type of coils covered by this chapter, while the flooded system is comparatively rare. With the flooded system the refrigerant distribution through the tubes depends on properly selecting the length of the feeds and the head of liquid imposed upon the liquid inlets. No auxiliary distributing devices CHAPTER 25. HEAT TRANSFER SURFACE COILS coil must be so arranged that the required suction superheat can be attained with a minimum sacrifice in the performance of the coil as a whole. It is general practice to attain this superheat within the coil . itself and not by the use of external heat exchangers or other auxiliary devices. : With thermal- expansion valves it is advantageous to keep the pressure drop through the refrigerant feeds as low as possible. The feeds are laid out to expose each to the same mean temperature difference so that it handles the same refrigerating load. A distributing means is imposed between valve and coil liquid inlets to divide the refrigerant equally among the feeds. Such a distr.butor shall be effective for distributing both liquid and vapor, since the entering refrigerant is a mixture of the Fig. 5. Types of Refrigerant Feed Distributing Heads are required, With the thermal valve system there are two factors to consider.; There must be, generally, more than one refrigerant, feed through the coil per thermal valve to keep the pressure drop through the refrigerant circuit within practical limits and to reduce the corresponding penalty in increased evaporating temperature. At the same time the 464 two. Fig. 5 shows three typical types of distributors. In distributor A the liquid and gas mixture from the thermal valve is led tangentially into a chamber. The coil feed connections extend outward radially at the top of this chamber. In distributor B the refrigerant is discharged at a high velocity through a central jet against the end plate, forming a uniform mixture of gas and liquid within the distributor, from which individual connections are led as shown. Iri type C the refrigerant enters at high velocity from the thermal valve and is discharged against the end plug in which the individual liquid feeds are closely arranged. These distribu tors can be used in either vertical or horizontal position-. Although there are other forms of distributors the above are typical examples. The individual liquid connections from the distributor to the coil inlet are commonly made of small diameter tubing and are all of the same length 465 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 and diameter in order to impose the same friction between the distributor and the coil. Since the thermal valves act in response to the superheat at the coil outlet, this superheat should be produced with the least pos sible sacrifice of active evaporating surface. Sometimes a single thermal valve is used per coil. In other cases multiple valves are used, with the coil divided across the air flow or parallel to the air flow as shown in Fig. 6. The arrangement of Fig. 7 should be avoided since it offers the disad vantage of unequal load on the two parallel circuits. Flow Arrangement The relative direction of flow of the air outside the tubes and the medium within them influences the performance of the surface. There are three types of relative flow in common use. Fig. 8A shows parallelflow in which the air and the medium in the tubes proceed through the coil in the same direction. Fig. 8B shows counter-flow in which the CHAPTER 25. HEAT TRANSFER SURFACE COILS Applications Heating coils in field assembled banks are used for a number of pur poses as described in Chapter 21. They may be arranged with the air flow vertical or. horizontal, although the latter is more common. For steam heating the coils may be set with the tubes vertical or horizontal. In the latter case the coil should be sloped to provide for condensate drainage. Because of the multi-circuit feed arrangement and the neces sity for avoiding air and water pockets, water heating coils are generally arranged with the tubes horizontal. Certain precautions must be taken against freezing. Where steam coils are used with entering air below freezing temperature, throttling the steam supply may result in freezing the condensate in the bottom of the coil if the tubes are of the variety not provided with internal distributing pipes, or an equivalent arrangement. Fig. 8. Flow of Media in Tubes in Relation to Air Flow medium in the tubes proceeds in a direction opposite to the flow of air. Fig. 8C shows cross-flow in which the air and the medium in the tubes pass at right angles to each other. Parallel flow is seldom used for the reason that a lesser mean temperature difference results than with counter flow. The counter-flow arrangement is almost universally used in brine or water coils to take advantage of the highest possible mean temperature difference for given entering water and air temperatures. It is also invariably used in coils fed with volatile refrigerant to take advantage of the higher air temperature for superheating the leaving gas. This arrangement assists complete evaporation and superheating of the re frigerant which is essential to proper operation of the thermal expansion valve. Cross-flow is common in steam heating coils, the temperature within the tubes being substantially uniform and the mean temperature difference the same whatever the direction of flow, relative to the air. Cross-flow is to be avoided in coils with volatile refrigerants on account of unequal loading of parallel circuits and danger of short circuiting of liquid refrigerant which will disturb proper functioning of the thermal expansion valve. 466 . If these are used, there is little danger of freezing the condensate as long as the leaving air temperature is not allowed to fall below about 40 F. As an added precaution with both steam and water coils the outside air inlet dampers are often closed automatically when the fan is stopped to avoid trouble caused by very cold outside air drifting in during off periods. A typical arrangement of water cooling coils is shown in Fig. 9. Some means should be provided to filter all the entering air to keep dirt and foreign matter from accumulating on the coils. The assembly is provided with a drip-pan to catch the condensate during summer dehumidifying duty and to collect the non-evaporated water from the humidifying sprays in winter. The drip connection should be made ample in size and liberally provided with plugged tees and crosses for cleaning. It should not be exposed to freezing temperatures in winter if the apparatus is used on winter humidifying duty. Access doors should be provided for servicing filters, humidifying nozzles, and fan bearings and for cleaning the coils. With certain designs of coils when used for dehumidifying, eliminators must 467 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 be used beyond the coil to catch any water which may be blown into the air stream. It is customary to include these eliminators when the air velocity exceeds about 450 fpm with the individual fins and about 600 fpm for the continuous flat fin type. Where a number of coil sections are stacked one upon another, and where the velocities are low, so that eliminators need not be used, occasional trouble results when water splashes down from one coil to the next and blows out into the air stream. In such cases drip troughs as shown in Fig. 10 are used to collect this water and conduct it to the condensate pan. ' . Sometimes finned surface coils on summer cooling and dehumidifying duty are provided with water sprays. These sprays are of two types. In the first type a set of spray nozzles is arranged for intermittent cleaning. The operator can wash the coils off as frequently as necessary. These By-pass dampers Fig. 10. Coil-Arranged with Drip Trough Fig. 11. Recirculating Spray System for Cleaning Coils sprays are not operative when the system is in use and no recirculating pump, is provided. The second arrangement requires a collecting tank and a recirculating pump. The water is in circulation whenever the apparatus is in operation, and assists in keeping the coil clean and in absorbing odors. Fig. 11 illustrates such an arrangement. Wherever air by-passes are used around a coil on summer duty for control purposes, it is of advantage to direct only return air through the by-pass rather than a mixture of return and outside air. The casing should be arranged accordingly. To maintain the air quantity handled by the fan reasonably constant, and to assure the required design quantity of by-passed air when the by-pass damper is open, cooling coil banks are frequently furnished with both face and by-pass dampers as shown in Fig. 9. Although both heating and cooling coils are made of sufficient strength to take up expansion and contraction arising within themselves, care should be taken to avoid imposing strains from the piping on to the coil connections. (See Chapters 16 and 17). 468 CHAPTER 25. HEAT TRANSFER SURFACE COILS HEAT TRANSFER AND AIR FLOW RESISTANCE The transfer of heat between the heating or cooling medium and the air stream is influenced by several variables: 1. The magnitude of the driving force, i.e., the temperature difference. 2. The design and surface arrangement of the coil. 3. The velocity and character of the air stream. 4. The velocity and character of the medium in the tubes. The driving force is usually taken as the logarithmic mean temperature difference for heating or cooling without dehumidification. For combined cooling and dehumidification, a special measure of the propelling force is used as described later. Logarithmic differences are generally employed in practice although there are special flow relationships used, such as cross-flow, where they do not strictly apply. With volatile refrigerants there is often an appreciable pressure drop and corresponding change in evaporating temperature through the refrigerant circuit. The problem is further complicated by the fact that the refrigerant is evaporating in part of the circuit arid superheating in the remainder. In spite of this, heat transfers and ratings for coils using volatile refrigerants are usually based in practice on a refrigerant temperature corresponding to the average pressure in the coil. . . The design and surface arrangement of the coil includes such items as materials, type, thickness,: height and spacing of the fins, and the ratio of this surface to that of the tube, the use of the staggered or in-line tube arrangement,' and provisions to increase the air turbulence such as the use of corrugated as.against flat fins. Staggered tubes increase the total heat transfer as against the in-line arrangement and corrugated fins are more effective than flat. Of especial importance is the bond between fin and tube. . The velocity of the air usually considered is the coil face velocity. This bears a varied relation to the actual velocity over the surface, de pending upon the individual coil design. As long as a fixed design of coil is under consideration face velocities may be used, but they may be unsatisfactory in comparing different designs, as it is the actual surface velocity that is significant. The air volume is often based on standard air at 70 F and a barometric pressure of 29.92 in. Hg. The use of air volume in coil rating information may be misleading. The significant value is mass velocity in pounds per minute and not cubic feet pier minute, because for a fixed volume the corresponding weight may vary widely, depending upon the air density, temperature and barometric pressure under consideration. At the same mass air velocity, varying performance can be obtained depending upon the turbulence of the air flow into the coil and upon the uniformity of distribution of air over the coil face. The latter is very im portant in obtaining reliable test ratings and in realizing rated performance in practical installations. The resistance through the coils will assist in properly distributing the air, but where the inlet duct connections are brought in at sharp angles to the coil face, the effect is frequently bad and there may even be reverse air currents through the coils. This 469 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 reduces the capacity, but can be largely avoided by proper layout or by the use of directing baffles. ' The heat transfer depends also upon the velocity of the medium in the tubes and upon its character, whether flowing water, condensing steam or evaporating volatile refrigerant. Heat transfer rates expressed as Btu per square foot of internal surface per degree logarithmic mean effective temperature difference between the fluid and tube wall are, for example, about 150 to 300 for evaporating dichlorodifluoromethane, about 350 to 1200 for water at 2 and 6 fps and about 1200 for condensing steam. The influence of the medium in the tubes on the overall heat transfer rate is, therefore, apparent. Because of these variables, reliable rating and performance information for any design of coil must be based on actual tests on that coil under the expected conditions of operation. A comparison between the perfor mance of two designs, unless based on such tests on each, may lead to entirely erroneous conclusions. ^ PERFORMANCE OF HEATING AND COOLING COILS Heating and cooling coils are essentially heat exchangers and as such their performance depends in general upon: 1. The overall coefficient of heat transfer from the fluid within the coil to the air it heats or cools. 2. The mean temperature difference between the fluid within the coil and the air flowing over the coil. 3. The physical dimensions of the coil. Thus, for any one definite operating condition, the heating or cooling capacity of a given coil is expressed by the following basic formula: where Q u MTD A Q = U X MTD X A (1) total heat transferred by the coil, Btu per hour. overall coefficient of heat transfer, Btu per hour per square foot of external coil surface per degree Fahrenheit temperature difference between the fluid within the coil and the air flowing over the coil, mean temperature difference, degrees Fahrenheit between the fluid within the coil and the air passing over it. (This is commonly taken as the logarithmic mean temperature difference), external surface area of the given coil, square feet. The performances of heating and cooling coils are influenced by the same factors in all but one very important exception, that is, when cooling coils operate wet or act as dehumidifying coils. For this reason, in the discussion which follows, heating and dry cooling coils are treated as one group and dehumidifying coils as another. OVERALL COEFFICIENT OF HEAT TRANSFER Of all factors affecting the performance of heating or cooling coils, the overall coefficient of heat transfer is the most difficult to determine as it in itself is influenced by several factors depending upon coil design and conditions of operation. 470 CHAPTER 25. HEAT TRANSFER SURFACE COILS Considering any coil, whether of bare pipe or of finned type, the overall heat transfer coefficient for a given size and design of coil can always be considered as a combined effect of three individual heat transfer coef ficients, namely: . 1. The film coefficient of heat transfer between air and the external surface of the coil, usually given in Btu per hour per square foot external surface per degree Fahrenheit mean temperature difference. 2. The coefficient of heat transfer through the coil material--tube wall, fins, ribs, etc. 3. The film coefficient of heat transfer between the internal surface of the coil and the fluid flowing within the coil, usually given in Btu per hour per square foot internal surface per degree Fahrenheit mean temperature difference. These three individual coefficients acting in series result in an overall coefficient of heat transfer in accordance with the basic laws. For a bare pipe coil the overall coefficient of heat transfer, whether for heating or for cooling (dry), can be expressed by a simplified basic formula as follows: where V= -A + Jl + _L Af ^ k ^ Aa (2) U = overall coefficient of heat transfer, Btu per hour per square foot external surface per degree Fahrenheit mean temperature difference between air and fluid within the coil. hi -- film coefficient of heat transfer between the internal surface of the coil and the fluid flowing within the coil, Btu per hour per square foot internal surface per degree Fahrenheit mean temperature difference between that surface and the average fluid temperature. ha = film coefficient of heat transfer between air and the external surface of the coil, Btu per hour per square foot external surface per degree Fahrenheit mean temperature difference between the mass of air and the external surface. k = conductivity of material from which the bare pipe is constructed, Btu per hour per square foot per degree Fahrenheit per inch thickness. L = thickness of tube wall, inches. R = ratio between external and internal surface of the bare tube, usually varying from 1.03 to 1.15 for the tube used in typical heating or cooling coils. This ratio R is inserted in the formula in order to place internal fluid coefficient of heat transfer on the basis of external surface. Frequently, when pipe or tube walls are thin and of material having high conductivity (as is the case in construction of typical heating and cooling coils) the term L in Equation 2 becomes negligible and is generally disregarded. (The effect of the term L in typical bare pipe heating or cooling coils seldom exceeds 1 to 2 per cent of the overall coefficient). Thus, in its simplest form, for bare pipe: V =-------- --------R_ , _1_ hi + Aa (3) r or nnnea cons tne iormuia1 tor tne overall coefficient of heat transfer can be conveniently written: U= Af xAa (4) "Rational Development and Rating of Extended Air Cooling Surface, by H. B. Pownall (Refrigerating Engineering, October, 1935, p. 211). 471 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 25. HEAT TRANSFER SURFACE COILS in which the term x, called the fin efficiency is introduced to allow for the resistance to heat flow encountered in the fins. The term R, in this case, is the ratio of total external surface to internal surface. For typical designs of finned coils for heating or cooling, this ratio varies from 10 to 30. The use of this term R is again introduced to place the internal fluid film coefficient of heat transfer on a basis of ex ternal surface. Whereas the Equation 4 appears to be comparatively simple, it is actually extremely difficult to use in practice due to lack of handbook data relating to its component terms fi, x and lb.. . The difficulty of obtaining the values of terms hi, x and lb is due to the fact that they in themselves depend upon several factors. hi,The internal fluid film coefficient, depends upon: (1) nature of the fluid--i.e., its chemical composition, (2) velocity of the fluid within the tubes or pipes, (3) temperature of the fluid,' (4) whether fluid is boiling or not, e.g., it may be boiling refrigerant or cold water, (5) the rate of boiling or the heat load upon unit area, and (6) whether the fluid is condensing, evaporating or liquid without changing state. The air film coefficient of heat transfer, ha, in turn depends upon: (1) air velocity over the tubes and the fins, (2) tube diameter, (3) tube spacing, (4) tube arrangement (staggered or parallel), (5) fin spacing, (6) fin design (flat or corrugated), and (7) air temperature and density. The fin efficiency term x is even more difficult to obtain by computation because it involves very complicated differential equations. Practically, however, it is known that the fin efficiency term * is affected by: (1) external fin diameter or length, (2) internal fin diameter, actual or effective, (3) fin thickness, (4) material of construction, (5) fin cross-section area in radial direction, and (6) bond between fins and pipe or tubes. From the foregoing, it is obvious that rating or selection of cooling or heating coils requires careful consideration of all factors involved and that hasty application of the involved theory is apt to produce unsatis factory results. Fortunately, for all practical purposes, many of the complex relation ships given above can be combined into one and the effect be measured by laboratory tests with a comparative simplicity for any one given coil under fixed conditions of operation. Thus, for a given coil design, either for heating or for dry cooling, its overall coefficient of heat transfer can be expressed by a simple empirical formula: where U = CWn . (5) U = overall coefficient of heat transfer, Btu per hour per square foot external surface per degree Fahrenheit mean temperature difference between air and internal fluid. W = air mass velocity, pounds per hour per square foot of coil face area. n = exponent depending upon air turbulence which is affected by: (1) tube diame ter, (2) tube spacing and arrangement, (3) fin design and spacing, and (4) coil depth. For values of n for typical cooling coils see Table 1. C = constant which is dependent upon all other factors affecting U as explained in the previous discussion. GRAPHICAL SOLUTION OF A COIL CAPACITY PROBLEM After the value of the overall coefficient of heat transfer for any given cooling or heating coil has been determined, it remains to compute the 473 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 coil capacity in relation to the total air flow over the coil as well as in relation to the overall coefficient of heat transfer. The capacity of any heating or dry cooling coil can be expressed by either one of the two following equations: ft = W X 0.24 X ft - h) (6) where and ft = total coil capacity, Btu per hour. . W -- total weight of air passing over the coil, pounds per hour. 0.24 = specific heat of air, Btu per pound per degree Fahrenheit. . <i -- h = difference in temperature of air entering and leaving coil, degrees Fahrenheit. ' ' ft = U X MTD X A (7) where ' ft = total coil capacity, Btu per hour. U -- overall coefficient of heat transfer between the air and the fluid within the coil, Btu per hour per square foot per degree Fahrenheit. MTD = logarithmic mean temperature difference, degrees Fahrenheit. A = total external coil surface, square feet. Obviously, the closer thedeaving air temperature approaches the tem perature of the fluid within the coil, the greater will become the value of the total capacity, Qlt as determined by Equation 6, because h -- t2 increases; and on the other hand, the smaller will become the total capacity, as computed by Equation 7, because MTD decreases. Since the Equations 6 and 7 are independent of each other, the graphical balance between them is the simplest method of solution. A typical graphical approach to solution of the coil capacity is shown in Fig. 12. Obviously, the heat loss or gain in the heating or cooling medium must equal the heat gain or loss of the air. Therefore, the actual coil capacity must lie at the intersection of the straight line curve .representing Equa tions 6 and 7. COIL PERFORMANCE OPERATING WITH DEHUMIDIFICATION The foregoing theory pertaining to heating and cooling coils (operating dry) applies equally to the performance of cooling coils .operating with dehumidification. However, there are also other factors which affect the performance of cooling coils operating wet which have no influence on either heating coils or cooling coils operating without dehumidification. Since the force which causes condensation of moisture from the air upon the external surface of the cooling coil has its origin in the vapor pressure difference between the mass of air passing over the coil and that corresponding to temperature of the wetted coil surface, it is obvious that the latent coefficient of heat transfer depends upon several factors: 1. The average dew-point temperature of the air passing over the cooling coil. 2. The average temperature of the external coil surface (fins and tubes) exposed to the air stream. 3. Other factors applicable to dry cooling coils, as discussed, also affect the coefficient of latent heat transfer. 474 CHAPTER 25. HEAT TRANSFER SURFACE COILS Furthermore, the coil may be wet throughout or wet at the cooler points and dry elsewhere. In the latter case the action is partly as a dry, and partly as a dehumidifying surface. As it is difficult to determine the proportions, approximations must be used. Since the dew-point tem perature of the air passing over the coil is dependent upon the inside and outside atmospheric design conditions, it is not subject to control at will and must be accepted as found. Consequently, regulation of the average temperature of the external coil surface is the primary means for con trolling the moisture removal from the air passing over the coil. Total Capacity of Coil Operating With Dehumidification While a coil operating dry transfers heat to or from the air by merely changing the temperature of the air, the cooling coil operating wet also TEMPERATURE OF AIR LEAVING COIL. DEG FAHR Fig. 12. Capacity Balance Chart for Dry Cooling Coil transfers heat from the air by condensing some of the moisture carried by it. Because of this, the dry coils are said to transfer sensible heat only, while the wet cooling coils are said to transfer latent as well as sensible heat. The sum of sensible and latent heat transferred by a dehumidifying. cooling coil is the total heat. For practical reasons, the latent heat removal capacity of cooling coils is usually given as a percentage of the total heat removal, and this percentage is called the heat load ratio. Although much research has been already conducted and more is in progress, there is no general agreement as to the most satisfactory and . convenient manner in which to rate dehumidifying coils. A large number of methods are now in use, most of them combinations of theory and empirical presentations of test data. Information, is given, usually in the form of tables or curves to determine the total cooling: capacity, with supplementary devices to ascertain the proportions of sensible and latent. 475 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Some of the methods now used require trial and error solutions and others are of very questionable accuracy, although the error may be small when applied within narrow limits of the several variables. In rating dehumidifying coils, there are two requirements. The total capacity must be determined and the proportion of sensible and latent heat transfer ascertained. These determinations often involve an average coil surface temperature. This may be determined experimentally by the use of thermocouples or calculated theoretically from other test data. Sometimes, a fictitious effective temperature is used, determined by the point of intersection between the saturation curve on the psychrometric chart and a straight line drawn through points representing the entering and leaving air conditions. The total cooling capacity is determined in a variety of ways, of which the following are the most usual: 1. The use of surface or overall heat transfer coefficients in conjunction with dry-bulb mean temperature differences. The result is corrected for dehumidification by means of functions for: (1) the temperature differences, (2) the expected total to sensible load ratio, and (3) empirical factors determined from test. 2. The use of surface or overall coefficients for combined sensible and latent heat removal with a wet coil, using as the driving force the difference between enthalpy of the entering air and that of saturated air at either the surface or the refrigerant temperature. 3. The calculation of sensible and latent capacities separately. The sensible is based on dry-bulb mean temperature difference ana heat transfer coefficient while the latent is determined using a dew-point mean difference and a corresponding latent heat transfer coefficient. 4. The use of a contact factor or ratio of heat removed to heat removable. This factor is a function of coil depth and air velocity, is experimentally determined for each design and used in conjunction with a so-called surface temperature. Average Effective Coil Temperature The relationship between the average external coil surface temperature and the dehumidifying capacity of cooling coils has been studied by several investigators and their studies have established an empirical but practically accurate rule: If air at given conditions of dry- and wet-bulb temperature is passed over a cooling coil of constant external surface temperature, then the latent heat removed by the coil is always a definite percentage of the total heat removed--this is practically so regardless of the air velocity over the coil, the coil design, the kind of cooling medium within the coil or its flow characteristics. It is obvious that coil designs and the common cooling mediums em ployed do not result in a uniform external coil surface temperature; however this uniform condition is not necessary for the rule to be usefully applied. All that is needed is that a method be found for determining the average integrated effective external overface temperature. The . actual temperatures of the various parts of fins or tubes have relatively little effect upon the ratio of latent to total heat transfer. This rule is of importance in the testing, rating and selection of cooling and dehumidi fying coils, when the straight line method is used for finding the average effective coil surface temperature. If a psychrometric chart is constructed so that equal increment^ along the horizontal axis represent equal changes in sensible heat content and equal increments along the vertical axis represent equal changes in latent 476 CHAPTER 25. HEAT TRANSFER SURFACE COILS heat content of air, then on such a chart the performance of a dehumidi fying cooling coil may be conveniently represented by a straight line, as shown, in Fig. 13. Point A represents the condition of return or recircu lated air, point B that of outside air, point C the mixture of % recirculated air with outside air, point D.represents the condition of air leaving the cooling coil, and point E represents the average effective temperature of the external cooling coil surface. On Fig. 13 the horizontal distance between points C and D represents the sensible heat removed from the air, while the vertical distance represents the .weight of moisture or the latent heat removed from the air. Another important practical feature is that a line drawn anywhere else within the body of the chart parallel to the line C-E represents the same ratio of latent to total heat removal To enhance the practical usefulness of the psychrometric chart illus trated in Fig. 13, a set of marked master slope lines are included. The value of this arrangement is easily illustrated by the graphical example shown. . Example 1. To determine the required average effective external coil surface tem perature. Given: (1) Air entering cooling coil at temperature of 83 F dry-bulb and 69 F wet-bulb. (2) Ratio of latent to totai heat that must be removed from air is 35 per cent. Required: To find the average external coil surface temperature. ____ _ VA/. uian tuiuugii pimn it, di uic origin oi cne neat load ratio tines, a line N-0 with a slope of 35 per cent in accordance with scale S. (2) Mark in the body of the chart, point P representing the condition of air entering the cooling coil at 83 F dry-bulb and 69 F wet-bulb. (3) Through point P draw a line P-Q parallel to line N-O. (4) The line P-Q intersects the saturation curve at 51 F, which means that the effective external coil surface temperature must be maintained at 51 F in order to obtain the desired 35 per cent latent to total ratio of heat removal from the air passing over the given cooling coil. 477 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Overall Coefficient of Heat Transfer ! The overall coefficient of heat transfer for cooling coils operating with dehumidification is actually a sum of two overall coefficients: (1) the sensible overall coefficient due to flow of sensible heat under the pressure of temperature difference between the air and the cooling medium and (2) the latent overall coefficient due to flow of the latent heat of con densation from the moisture condensed due to difference in temperature between air dew-point and the external coil surface. . The relationship of the sensible and latent overall coefficients to the average external coil surface temperature and the temperature of the cooling medium within the coil is very complicated and, therefore, not. subject to practical computations. Fortunately, an empirical relation ship has been established by experimental data which afford a practical means of determining heat transfer in cooling coils operating with dehu midification. On the basis of experimental data, it has been established that the total heat (sensible plus latent) transferred to a dehumidifying cooling coil by the air passing over it is for all practical purposes a function of the difference between the wet-bulb temperature of the air and the external coil surface temperature: The general formula for total (cooling and dehumidification) capacity of any given wet cooling coil operating at. a definite fixed set of conditions can be expressed by the equation: Q = U X MTD x A (8) where Q = total (sensible and latent) heat transferred by the coil, Btu per hour. V = overall total (sensible plus latent) coefficient of heat transfer, Btu per hour per square foot of external coil surface per degree Fahrenheit difference between the wet-bulb temperature of the air passing over the coil and the temperature of the cooling medium within the coil. MTD = mean temperature difference, degrees Fahrenheit between the wet-bulb temperature of the air passing over the coil and the temperature of the cooling medium within the coil. - A = external surface area of the given coil (fins and tubes), square feet. . The primary difficulty which accompanies the use of Equation 8 is that further computations are necessary to obtain the average (effective) external coil surface temperature before the latent to total heat removal ratio can be ascertained. A practical means of determining effective coil surface temperature has been determined2. For all practical purposes the performance of a given cooling coil (operating wet or dry) can be presented in a graphical form without sacrifice of accuracy within the limits of most air conditioning practice. A typical graphical presentation of a cooling coil performance (operating with dehumidification) is shown in Fig. 14. An analysis of this chart indicates how a given coil's performance may be affected by a change in any of the variables enumerated herewith. 1. Wet-bulb temperature of air entering the coil, degrees Fahrenheit. 2. The average (effective) external coil surface temperature, degrees Fahrenheit. Graphical Method of Determining Finned Coil Capacities Described, by E. P. Wells (Heating, Piping, and Air Conditioning, December, 1936. p. 665). ........................ :- . 478 CHAPTER 25. HEAT TRANSFER SURFACE COILS 3. Mass air velocity through the cooling coil, pounds per hour per square foot coil face area. (This mass velocity includes linear velocity as fpm and air density as pounds per cubic foot). Construction of a coil capacity chart such as shown in Fig. 14 is accom plished as outlined herewith: 1. A series of tests are run to determine the sensible, latent and total coil capacity, changing one at a time such variables as: air velocity, inlet air dry-bulb, inlet air wetbulb, average refrigerant temperature within the coil, and total load upon the coil. 2. From test data obtained in (1) the ratio of latent to total heat removal is computed for various test runs and tabulated against the wet-bulb temperature of air at coil, inlet and total coil capacity: 3. The three axes of the nomogram on the left side of the chart are drawn in such a mariner that the C axis represents the differences in total heat content between the air at wetrbulb .temperature along B axis and air at wet-bulb temperature along A axis. Thus, the C axis represents the total heat (Btu per pound of air, sensible and latent) which could be removed from the air at some iniet wet-bulb temperature on B axis if the coil heat transfer efficiency Were 100 per cent and the wet-bulb temperature of the air could be reduced to some average (effective) external coil temperature on A axis. For example if a straight line is drawn through 72 F wet-bulb temperature of entering air on axis B and the 55 F average effective coil (external surface) temperature on axis B, then this straight line will intersect the C axis at 12.6, which figure represents the difference in total heat content of air between 72 and 55 F wet-bulb temperature. 4. Next scale Q is drawn to cover the range of the likely practical loading for the given coil in Btu per hour per square foot coil face area. . 5. Lastly, the diagonal mass air velocity lines are drawn in at the intersection of various values on C axis and the corresponding values on the Q scale. The values on the Q scale corresponding to various values on C axis are obtained by multiplying the 479 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 values on C axis by mass air velocity and by heat transfer efficiency of the given coil which depends upon coil design and refrigerant used. ^' 6. Parallel to the Q scale is also shown what is commonly referred to as the At scale. This scale gives the difference between the average effective coil (external surface) temperature and the average temperature of refrigerant within the coil. As shown in Fig. 14, the At scale applies only to a direct expansion coil of one definite physical design. Any change in coil design usually results in change of At values. Coifs with Water as the Cooling Medium All that has been brought out in discussion of the coil capacity chart in Fig. 14, with the exception of the At scale, holds equally well for coijs employing either vapor refrigerant or water as the cooling medium. CHAPTER 25. HEAT TRANSFER SURFACE COILS 2. Water velocity in tubes, usually in fpm. (This depends on internal tube diameter as well as the number of water circuits). 3. Coil design factor which represents the ratio of external fin and tube surface to internal tube surface. 4. The water temperature rise through the coil, degrees Fahrenheit. Performance of Coils and Refrigeration Compressor Practically all data published by various makers of direct expansion cooling coils are based upon maintaining a predetermined refrigerant temperature within the coils. While it is often possible to maintain a definite refrigerant temperature within a given cooling coil, for the greater part it is either impossible or impractical. This is due to the fact that the capacity of standard refrigeration compressors is usually fixed and in However, the At scale as shown is applicable only to direct expansion coils, i.e. coils employing some volatile refrigerant as the cooling medium. Determination of the difference between the average effective coil (external surface) temperature and the average water temperature within the coil, necessary to transfer the heat from the coil surface to the water, calls for a graphical solution similar to that shown on Fig. 15.' When .this chart is used in conjunction with Fig. 14 a simple and rapid means is provided for determining the cooling and dehumidification capacity of coils employing water (or brine) as the cooling medium. Factors affecting the performance of coils employing water as the cooling medium besides those shown on Fig. 14 are: , 1. Quantity of water flow through the coil, usually in gpm or lb per hour. 480 Fig. 16. Graphical Analysis of Coil-Compressor Performance -- . . ... . . matching a given cooling coil with a standard, compressor the capacity of the latter is often somewhat smaller or greater than that of the former. Consequently, very often the refrigerant temperature resulting within, a cooling coil and correspondingly the capacity of the coil-compressor com bination are not what they were originally calculated to be. .. In order to determine the actual performance of a given coil-compressor combination under varying conditions of operation, a graphical solution of the balance or "break-even" point is highly desirable. A typical method of graphical analysis of. a coil-compressor combination per formance is shown in Fig. 16, which is constructed in a manner described herewith: ... 1. On a piece of graph paper (with a uniform scale), the equipment capacity scale, total Btu per hour, is laid out along the vertical axis while the refrigerant suction tem perature scale is laid out along the horizontal axis. - 481 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 2. The performance curve of a given compressor with a definite condenser (com bination usually called a condensing unit) is plotted as a function of suction temperature corresponding to the saturation suction pressure at the compressor suction service valve for a given inlet water temperature and quantity supplied to the condenser. 3. The performance curve of the given cooling coil is next plotted as a function of mean suction temperature within the coil, the mass air velocity over the coil and the wet-bulb temperature of air entering the coil. . 4. The refrigerant pressure drop between the center of the cooling coil and the com pressor suction service valve is computed and converted into the terms of temperaturedifference. This temperature difference is then fitted in horizontally between the performance curves of the cooling coil and the compressor, as shown, and the total capacity of the coil-compressor combination is read along the horizontal line upon which the above mentioned temperature-difference segment falls. COIL SELECTION In the selection of a coil it is necessary to consider several factors: 1. The duty required--heating, cooling, dehumidifying. 2. Temperature of entering air--dry-bulb only if there is no dehumidification, dry- and wet-bulb if moisture is to be removed. 3. Available heating and cooling media. 4. Space and dimensional limitations. 5. Air quantity limitations. 6. Allowable resistances in air circuit and through tubes. 7. Peculiarities of individual designs of coils. . 8. Individual installation requirements; such, for example, as type of automatic con trol to be used. The duties required may be determined from information in Chapters 5, 6, 7 and 8. There may or may not be a choice of cooling and heating media, as well as temperatures available, depending upon whether the installation is new or is in combination with present sources of heating or cooling. Space limitations are dictated by the requirements of individual cases. The air quantity is influenced by a number of considerations. The air quantity through heating coils is often made the same as that necessary to handle the summer cooling load.. The air handled may be fixed by the use of old ventilating ducts as an aiir distribution system for new air conditioning apparatus, or may be dictated by requirements of satisfac tory air distribution or ventilation. The resistance through the air circuit influences the fan horsepower and speed. This resistance may be limited to allow the use of a given size of fan motor, or to keep the opera ting, expense low, or it may be limited by the maximum fan peripheral velocity which requirements of. quietness may permit. The ..friction through the water or brine circuit may be dictated by the .head available from a given size of pump and pump motor. As the fan and pump motor inputs represent a refrigerating load on cooling installations, it is eco nomical to keep them low. . Proper performance of a surface heating or cooling coil depends upon correct choice of the original equipment and upon certain other factors. The usual coil ratings are based on a uniform face velocity or air. If the air is brought in at odd angles or if the fan is located so as to block part of the air flow, the performance as given in the manufacturer's ratings cannot usually be obtained. To obtain this performance it is necessary, also that the air quantity be adjusted on the job to that used in deter CHAPTER 25. HEAT TRANSFER SURFACE COILS mining the coil selection, and must also be kept at this value. The most common causes for a reduction of air quantity are the fouling of the filters and collection of dirt in the coils. These difficulties can be avoided ,by proper design and proper servicing. There are a number of ways in which coils may be cleaned. A common method is to wash them off with water. They can sometimes be brushed and cleaned with a vacuum cleaner.. In bad cases of neglect, especially on restaurant jobs where grease and dirt have accumulated, it is sometimes necessary to remove the coils and wash off the accumulation with steam, compressed air and water, or hot water. The most satisfactory solution, however, is to keep the filters serviced, and thus make the cleaning of the coils unnecessary. The proper selection of coils requires an understanding of, the necessities of each case and should be based on an economic analysis of the plant design as a whole. No general rule can, therefore, be laid down for the selection of heating or cooling coils. It is possible, however, to point out. the limits of usual, practice and to indicate the influence of the variables involved in the coil selection. Heating Coils - Steam and hot water heating,coils are usually rated within these limits: Air Face Velocity--200 to 1200 fpm, sometimes up to 1500 fpm. Steam Pressure--2 to 200 lb, sometimes up to 350 lb per square inch. Hot Water Temperature--150 to 225 F. Water Velocity--2 to 6 fps. ' Individual cases may deviate widely, but the tabulation given herewith will serve as a guide to usual heating practice: Delivered Air Temperature varies from about 72 F for ventilation only to about 150 F for complete heating. Steam Pressure--2 to 10 lb, 5 lb being common. Hot Water Temperature--150 to 225 F. Water Velocity--2 to 6 fps. . Water Quantity---Based on about 20 F temperature drop through a hot-water coil. Air Resistance--The total resistance through heating coils is usually limited to from % to % in. of water gage for public buildings, to about 1 in. for factories. ; The selection of heating coils is relatively simple as it involves dry-bulb temperatures and sensible heat only, without the complication of simul taneous latent heat loads, as in cooling coils. For a given duty, entering air temperature, and steam pressure it is possible to select several arrange- Table 2. Several Heating Coil Arrangements . Selection Steam pressure. Ib Der sq in. Temperature of air entering coil, deg F. Temperature of air leaving coil, deg F. Air quantity, cfm............. Coil face area, sq ft... Coil rows deep......... Face velocity, fom..... Air friction, in. water. 1 5 40 ' 129 10,000 33.3 2 300 0.044 2 5 40 129 10,000 12.5 3 800 0.396 3. 5. 40 129 . 10,000 . 7.50 ; 4 - 1330 1.077 HEATING VENTILATING AIR CONDITIONING GUIDE. 1940 merits of the same design of coil depending upon the relative importance of space, cross-sectional area, and air resistance. Table 2 shows an example. ... Cooling Coils The usual range of ratings for cooling and dehumidifying coils are enumerated herewith: r , ' Entering Air Dry-Bulb--60 tp 100 F. .Entering Air Wet-Bulb--50 to 80 F. ! Air Face Velocities--300 to 800 fpm, (sometimes as low as 200 and as high as 1200). Volatile Refrigerant Temperatures--25 to 55 F, at coil suction outlet. Water Temperatures--40 to 65 F. Water Quantities--2 to 6 gpm per ton, or equivalent to a water temperature range of from 4 to 12 F. Water Velocity--2 to 6 fps. . The ratio of total to sensible heat removed varies in practice from 1.00 to about 1.65, i.e., sensible heat is from 60 to 100 per cent of total, depending on the application. (See Chapter 21, Table 1). Required ratios may demand wide variations in air velocities, refrigerant tempera tures, and coil depth, so that general rules as to these values may be misleading. On usual comfort installations air face velocities between 400 and 600 fpm are frequent, 500 being a common value. Refrigerant temperatures will ordinarily vary between 40 and 50 F where cooling is accompanied with dehumidification. Water velocities will range from 2 to about 6 fps. When no dehumidification is desired, for which condition the dew-point of the entering air will be equal to or lower than the cooling coil tempera ture, the coil selection is made on the basis of dry-bulb temperatures and sensible heat transfers only, the same as with heating coils. It is possible also to choose various arrangements of face area, depth, air velocity, etc., for the same duty, as illustrated in Table 2 for a steam coil. Dehumidifying Coils The selection of coils for combined cooling and dehumidifying duty is more involved than for heating or sensible cooling and requires con sideration of both dry- and wet-bulb air temperatures. It is further complicated by the fact that the proportional amount of dehumidification required is also highly variable. The methods outlined previously under Heat Transfer and Resistance may be used to determine whether it is possible for a coil to perform the duty required. If entering and leaving air conditions are arbitrarily specified, the corresponding duty sometimes cannot be obtained at all without the use of reheat. As with heating and sensible cooling coils, there are combinations of face areas, depth, air velocity and refrigerant temperatures which will give the required per formance.- This is illustrated in Table 3. J It is possible as shown in Table 3 to perform approximately the same duty at a given, refrigerant temperature with small face area and large thickness or vice versa. The large face area coil will give low air velocity and resistance but high air quantities per ton. The coil of smal.l face area and great depth will require small air quantities per ton of refrigeration, 484 CHAPTER 25. HEAT TRANSFER SURFACE COILS Table 3. Various Cooling Coil Arrangements Selection 1 Total cooling capacity, tons 100 Sensible cooling capacity, tons... 69 Latent cooling capacity, tons. 31 Ratio total to sensible heat. 1.45 Air quantity, cfm______ __ 47,800 Clm per total ton. 478 Face velocity, fom- .... 325 Resistance, in. water......... 0.11 Coil face area, sq ft... .... j 147 Coil rows deep................... 4 Coil evaporator temp, deg F | ! 45 2 100 69 31 1.45 41,700 0.27 99.0 6 45 3 100 69 31 1.45 37,100 371 500 0.51 74.2 8 45 4 100 69 31 1.45 46,800 468 600 0.37 78.1 4 38 mgn resistance ana nigh air velocities. As shown also in Table 3 the same sensible, latent and total cooling capacity may be obtained with various r_ efrigoe__r_a_n_t__te__m_ ,p--e--r-a--t-u--r-e-s by ppr.uoppeur uchiuoiiucee ooif ccooiill,. Ti hniiss mmaakkeess iitt ppoossssiibbllee to keep the evaporating tempoerattuiire hhiiog-hh enough -t-o---c--a---r-r-y- I-tLh-e' load' w'ith' a chosen size of condensing unit. High evaporating temperatures with correspondingly, small compressor operating expense can be attained but at the expense of coil surface, air quantity or both. The choice will be determined by the necessities of individual installations. ~---- ----- ` -- --- . ui vuiume control is used. It is necessary that not only the total capacity but also the sensible and latent cooling requirements both be met. The installation of an excess of coil will result in an increase in. total capacity, but not a proportional gain in latent heat capacity. On installations controlled from dry-bulb tem perature the operating time will be shortened because of the added sen sible cooling capacity. The result will be less moisture pick-up than calculated, and higher relative humidity. If an oversize condensing unit Table 4. Capacity Balances for Maximum and Minimum Load Conditions Conditions Capacity in Tons Required at peak load conditions........ ............. Required at minimum load conditions............ Peak load equipment balance........... ........ .......... Same equipment balanced at minimum load conditions..... ,....................................................... Same equipment balanced at maximum load conditions with 40 per cent by-pass Same equipment balanced at minimum load conditions with 38,800 Btu per hour reheat Total 10.90 6.62 10.90 9.85 8.38 6.62 Sensible 7.90 3.36 7.90 6.58 5.05 3.36 Latent 3.00 3.26 3.00 3.26 3.33 . 3.26 485 . Total Sensible 1.38 1.98 1.38 1.50 1.66 1.98 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 is installed the opposite situation will take place. The relative humidity will be lower than estimated. This is not generally a disadvantage except that it results in a greater load from outside air than calculated, as well as in increased power; consumption. If oversize equipment is furnished, a balance should be made to assure that the ratio of total to sensible capa city is the same as in the estimated load. Sometimes arbitrary air quantities are specified for ventilation or other reasons independent of the selection of the cooling coil. As shown in Table 3, the coil selection can be altered to take care of various air quantities for the same duty. Where coil and condensing unit are selected for the peak load condition, and the sensible load partially disappears due to fall of outside tempera ture or other cause, the condensing unit and coil rebalance. This may result in more sensible capacity than required at the light load condition and less latent in proportion, with an increased relative humidity in the conditioned space. Such a condition, for a typical installation, is shown in Table 4. If approximately 40 per cent of the total air is by-passed, the condition will be improved as indicated. The situation could be entirely avoided by using reheat. With sufficient reheat, it is possible to handle any ratio of sensible and latent loads and maintain the design temperature and humidity. Care should be taken to avoid freezing at light loads. In general, freezing occurs when the coil surface temperature falls to 32 F. With usual coils for comfort installations, this will not occur unless the evapo rating temperature at the coil outlet is about 20 to 25 F. The exact value depends on the design of coil and the amount of loading. Although it is* hot customary to choose coil and condensing units to balance at low tem peratures at peak loads, there is danger of this occurring when the load decreases. This is further aggravated if a by-pass is used so that less air is passed through the coil at light loads. It may be even worse if the control is arranged for decrease of inside temperature with fall of that outside. Freezing can be avoided by making the full.load balance a high evaporating temperature and checking the balance at the minimum load condition. . REFERENCES A.S.H.V.E. Research Report No. 997--Heat Transfer from Direct and Extended Surfaces with Forced Air Circulation, by G. L. Tuve and C. A. McKeeman (A.S.H.V.E. Transactions, Vol. 40, 1934, p. 427). A.S.H.V.E. Research Report No. 1029--Performance of Fin-Tube Units for Air Heating, Cooling and Dehumidifying, by G. L. Tuve (A.S.H.V.E. Transactions, Vol. 42, 1936, p. 99). , A.S.H.V.E. Research Report No. 1066--Performance of Fin-Tube Units for Air Cooling and Dehumidifying, by G. L. Tuve and C. A. McKeeman (A.S.H.V.E. Trans actions, Vol. 43, 1937, p. 367). A.S.H.V.E. Research Report No. 1099--Performance of Surface Coil Dehumidifiers for Comfort Air Conditioning, by G. L. Tuve and L..J. Seigel (A.S.H.V.E. Transactions, Vol. 44, 1938, p. 523). - Heat Transmission in Cooling Air with Extended Surfaces, by W. L. Knaus (Refriger ating Engineering, January, 1935, p. 23, February, 1935, p. 82). , Dehumidification of Air with Coils, by William Goodman (Refrigerating Engineering, October, 1936, p. 225). Extended Surface Cooling Units, by R. H. Swart (Refrigerating Engineering, February, 1938, p. 107). , s Chapter 26 SPRAY EQUIPMENT Air Washers, Apparatus for Direct Humidification, Spray Generation and Distribution, Air Dehumidification with . Washers, Water Main Temperatures, Atmospheric Water Cooling Equipment, Design Wet-bulb Temperaturesfor Water Cooling, Cooling Ponds, Winter Freezing AIR humidification is effected by the vaporization of water and always requires heat from some source. This heat may be added to the water prior to the time vaporization occurs or it may be secured by a transformation of sensible heat of the air being humidified to latent heat as the vapor is added to the air. The thermodynamics of the process are discussed in Chapter 1. Dehumidification consists of the removal of moisture from air and may or may not involve the removal of heat from the air-vapor mixture. With spray equipment dehumidification of air necessitates the removal of heat. AIR WASHERS Air washers may be used as either humidifiers or dehumidifiers de pending upon the method of operation and the temperature of the spray water. The functions of an' air washer are to regulate the moisture and heat content of air passing through it and to remove dust and dirt from the air. Air washers are not as effective as air filters in the removal of dust and dirt. The construction of commercial air washers is indicated in Figs. 1 and 2. Any air washer consists essentially of a chamber through which the air passes in intimate contact with water. The lower portion of the washer chamber serves as a sump for the spray water. Contact between the air and the washer water is secured: (1) by breaking the water into a very fine mist, (2) by passing the air over surfaces which are continuously wetted by water, or (3) by a combination of water sprays and wetted plates. Scrubber-plate types of washers are used largely to wash heavy reclaimable products from the air, and are generally composed of one to three eliminator-type baffle scrubber plates across the air stream. Water is supplied at the tops of the scrubber plates by flooding nozzles placed across the top of the washer. Spray washers have one or more banks of water atomizing nozzles placed in the air stream above the level of the water in the sump. The direction-of the water sprays may be against the air stream, with the air stream, or with one bank- spraying with the air stream and one against it. The number of 487 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 nozzles required depends upon their design, the quantity of air handled, and the arrangement of the nozzles. Scrubbers generally consist of eliminator-type baffle plates placed in the air stream to cause several reversals of the direction of air flow. The scrubber plates are more effective as air cleaners than as humidifiers. All washer chambers should have inlet diffuser plates to aid in producing more uniform air flow through the washer spray chamber. These inlet vanes also aid in preventing spray water from being thrown into the air duct ahead of the washer. At the outlet end of the washer suitable flooded eliminator plates, which will cause from 4 to 6 reversals of the direction of air flow, should be installed for the purpose of removing drops of unvaporized water from the leaving air. When the air carries Fig. 1. Typical Single Bank Air Washer Fig. 2. Typical Two Bank Air Washer certain substances mixed with it, the spray water may become acidulated and special consideration must be given to the materials used, to reduce the corrosive action. Essential items in air washer operation are: uniform distribution of the air across the chamber section above the level of the water in the sump; moderate velocities of air flow, 300 to 600 fpm in the spray cham ber; an adequate amount of spray water broken up into a fine mist throughout the air stream; sufficient length of air travel through the water spray and over thoroughly wetted surfaces; and the elimination of free moisture from the air as it leaves the unit. Washers are sometimes.arranged in two or more stages to cool through long ranges or to increase the overall efficiency of heat transfer between the air and the heating or cooling medium. A multi-stage washer is 488 ' CHAPTER 26. SPRAY EQUIPMENT equivalent to a number of washers in a series arrangement. Each stage is in effect a separate washer. Usually the catalog capacity of a washer is expressed in cubic feet of air per minute and is based upon an air velocity of 500 fpm through the gross cross-sectional area of the unit above the tank. At this rating spray type washers handle about 2Y2 gpm of water per bank per square foot of area, that is, about 5 gpm per bank per 1000 cfm. These propor tions of air, water, area, and velocity may be departed from to meet the needs of. some particular job, but certain limiting relationships should be observed. For a single stage air washer, a 15 F drop in dry-bulb temperature of the air passing through the washer is about the maximum that should be anticipated. For greater decrease in dry-bulb temperature, multi-stage washers should be utilized. A rise of 6 F should be.the calculated rhaximum for the spray water. The area of a washer may be dictated by space limitations outside the washer, such as headroom, or by the inside space requirements, such as face area needed by a bank of cooling coils. The length of a washer is determined by the number of spray banks, or scrubber plates, and if cooling coils are installed in the unit, by the number of banks of coils. Roughly, a spray space of about 2 ft 6 in. in length is required for each bank of sprays, (the leaving eliminators require about 1 ft 6 in., entering eliminators about 1 ft). . The resistance to air flow through an air washer varies with the type of eliminators, number of banks of sprays, direction of spray, air velocity, type of scrubber plates, size and type of cooling coils if located in the washer. Manufacturers should be consulted to obtain the resistance for a particular installation. HUMIDIFICATION WITH AIR WASHER Air humidification , can be accomplished in three ways with an air washer. These are: (1) use of recirculated spray water without prior treatment of the air, (2) preheating the air and washing it with recircu lated spray water, and (3) using heated spray water. In any problem of air washing the air should not enter the washer with a dry-bulb tempera ture less than 35 F so that there will be no danger of freezing the spray water. When method 1 is used the principles of adiabatic saturation described in Chapter 1 are involved. The process is one of evaporative cooling as the dry-bulb temperature of the air is reduced and the total heat of the air and water-vapor mixture is unchanged. Moisture is added to the air and a part of the sensible heat of the initial mixture is transformed to latent heat as evaporation of some of the spray water takes place. Theo retically the spray water and the dry- and wet-bulb temperatures of the air should come to the wet-bulb temperature of the air. entering the washer, and the air should leave the washer adiabatically saturated at the entering wet-bulb temperature. Due to limitations of air washer construction and operation, air is not completely adiabatically saturated. This introduces an item into the-calculations which is known as humidi fying or saturating efficiency. This efficiency is the ratio of the actual 489 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 reduction of dry-bulb temperature to the reduction of dry-bulb tem perature theoretically possible. Expressed as a percentage humidifying efficienc.y is: . *. " "(h 7-- t,) /100" (,,l)N where . h = humidifying efficiency, per cent. (v = initial dry-bulb temperature, degrees Fahrenheit. - A = final dry-bulb temperature, degrees Fahrenheit. - l' = initial wet-bulb temperature of the entering air, degrees Fahrenheit. The humidifying or saturating efficiency of a washer is dependent upon the number of spray banks and nozzles, the effectiveness of the nozzles " in breaking an adequate quantity of water into a fine spray, the velocity of air flow through the water sprays, and the time of the contact of the air with the spray water. Other conditions being the same, low velocities F Aig 3. ir Washer with Spray Water Heating Arrangement of air flow are more conducive to higher humidifying efficiencies. The following may be taken as representative humidifying or saturating efficiencies of air washers for the conditions stated: . 1 bank--downstream........................................a--:.L;.CU.:'............60-70finpe-7r0ceonetr cent ' .. 1 bank--upstream.......................................--............,......... -..............: 65-75 per cent . 2 banks--downstream............................................................ ................ 85-90 per cent 2 banks--1 upstream and 1 downstream............ :........................... 90-95 per cent 2 banks--upstream........... .............-...... ---........... ............................... 90-95 per cent The air leaving the washer may require reheating to produce the required dry-bulb temperature and relative humidity. When air of a given specific humidity has a low initial dry-bulb tem perature it may be preheated before it enters a washer using recirculated spray water. The preheating of the air increases both the dry- and wet-bulb temperatures and lowers the relative humidity, but not the specific humidity of the air. With an increased wet-bulb temperature, the air is capable of accumulating more moisture by the process of adiabatic saturation and the final specific humidity and the final dry-bulb temperature of the air as it leaves the washer will be higher. An addition of sensible heat by the preheater takes place prior to the air entry into the washer. In the case of method 2 the process of humidification within the washer is similar to method 1. The final desired conditions are 490 CHAPTER 26. SPRAY EQUIPMENT secured by adjusting the wet-bulb temperature of the entering air and reheating when necessary. Method 3 involves heating the spray water to a temperature higher than the leaving air temperature. In passing through the heated spray, both the temperature and humidity of the air is increased. By properly controlling the spray water temperature, the air may be made to leave the washer in a completely saturated condition. Reheating the air will give the necessary final dry-bulb temperature and relative humidity. The water heater may be located in the washer sump, or external to it as in Fig. 3. APPARATUS FOR DIRECT HUMIDIFICATION Humidifiers may be divided into the following general types, according to the method of operation: (1) indirect, such as the air washer, which introduces moistened air; and (2) direct, which sprays moisture into the room. As in the cases of humidification by use of an air washer, the heat necessary for the vaporization of the moisture added to the air by direct humidification is secured either from heat stored in the spray water or by a transformation of sensible to latent heat in the air humidified. In the latter case the total heat of the air remains constant but the dry-bulb temperature of the air humidified is reduced. Direct humidification is usually preferable where high relative humidi ties must be maintained, but where there is little cooling or ventilation required. In comfort air conditioning, where both humidification and ventilation are required, the indirect humidifier is preferable. In indus trial applications, where the cooling or ventilation load is large and where very high relative humidities must be maintained, a combined system employing both direct and indirect humidifiers is sometimes used. Spray Generation Spray generation is obtained by (1) atomization, (2) impact, - (3) hydraulic separation, and (4) mechanical separation. . Atomization involves the use of a compressed air jet to reduce the water particles to a fine spray. With the impact method, a jet of water under pressure impinges directly on the end of a small round wire.: Where hydraulic separation is employed, a jet of water: enters a .cylindrical chamber and escapes through an axial port with a rapid rotation which causes it immediately to separate in a fine cone-shaped spray.- In the mechanical separation process, water is thrown by centrifugal force from the surface of a rapidly revolving disc and separates into particles suf ficiently small to be utilized in certain types of mechanical humidifiers. Spray Distribution Spray distribution is obtained by (1) air jet, (2) induction, and (3) fan propulsion. The air jet which generates the spray in atomizers also carries the spray through a space sufficient for its distribution and evaporation, and this method of distribution is termed air jet. Where distribution is obtained by induction, the aspirating effect of an impact or centrifugal spray jet is 491 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 utilized to induce a current of air to flow through a duct or casing, and this,air current distributes the spray. Fan propulsion obviously consists of the utilization of fans to entrain and distribute the spray. Industrial type direct humidifiers are commonly classified as (1) atomizing, (2) high-duty, (3) spray and (4) self-contained or centrifugal. . Atomizing Humidifiers There are several types of atomizing humidifiers, all of which rely upon compressed air as the atomizing and distributing agency, similar to the familiar method used in ordinary nasal atomizers. Compressed air (ordinarily about 30 lb per square inch) is supplied from a centrallylocated air compressor through pipe lines to the atomizing units. The air lines are usually horizontal and parallel to water lines which supply' water by gravity from a float tank. The water in the tank is maintained at a constant level slightly lower than the outlets of the atomizers them selves and is drawn constantly to the atomizer by aspiration when com pressed air is supplied. This aspiration ceases and the flow of water stops when the air supply is cut off. The water should not be supplied under pressure to atomizers because of the possibility of leakage, drip, or coarse spray which cannot be permitted when water is supplied by aspiration. High-Duty Humidifiers Water is supplied to high-duty humidifiers under high pressure (usually about 150 lb per square inch) through pipe lines from a centrally-located pumping unit. The spray-generating nozzle which is of the impact type is located in a cylindrical casing. A drainage pan provides for the collec tion and return of unevaporated water which flows through a return pipe to a filter tank, from which it is recirculated. A powerful air current is forced through the humidifier by means of a fan mounted above the unit. The air enters from above, is drawn' through the head, charged with moisture, and cooled to the wet-bulb temperature. It then escapes from the opening below at a high velocity in a complete and nearly horizontal circle. The spray is evaporated and the resulting vapor diffused. This distribution of fine spray over the maximum possible area promotes complete and rapid vaporization even at high humidities. . Spray Humidifiers ' This type of humidifier consists of an impact spray nozzle in a cylin drical casing with a drainage pan below it. The aspirating effect of the spray nozzle induces a moderate air current through the casing which distributes the entrained spray. The general method of circulating and returning the water is similar to that employed for high-duty humidifiers. A suitable pump and centrally-located filter tank are required. . Self-Contained Humidifiers The self-contained or centrifugal humidifier has the ability to generate and distribute spray without the use of air compressors, pumps, or other auxiliaries. These may be used either singly or in groups. In large installations, where suitable connections are provided to permit the cleaning and servicing of individual units without affecting the room as a whole, group control of the water and power may be employed. 492 CHAPTER 26. SPRAY EQUIPMENT AIR DEHUMIDIFICATION WITH WASHERS Moisture removal from an air-vapor mixture can be accomplished by use of an air washer so long as the temperature of the spray medium is lower than the dew-point of the air passing through the unit. The final dry-bulb temperature and the relative humidity of the air leaving a dehumidifier washer are dependent upon: the air velocity, the length of air travel through the sprays, the dry- and wet-bulb temperatures of the entering air, the spray temperature, the number of spray banks and nozzles, the quantity of spray medium handled, and the effectiveness of the nozzles in breaking the spray into a fine mist. Both-sensible and latent heat are removed in the process of dehumidi fication by cooling. Abstraction of sensible heat occurs during the entire time that the air is in contact with the spray medium. Latent heat removal takes place as condensation occurs. Therefore, the lower the spray temperature the greater the amount of moisture removal per pound of dry air, all other conditions remaining the same. Washers with two or more banks of sprays are usually selected for comfort air conditioning installations. Such washers will cool the air to within 1 or 2 F of the leaving spray water temperature. Where a limited supjply of cold water is available multiple stage washers may be used to an advantage. The cool water is pumped through the multiple spray systems in series. By this arrangement the entering air is cooled first by the warmer water and finally by the cooler water which gives the maximum amount of cooling with the minimum amount of water. The approximate temperatures of water from wells at depths of 30 to 60 ft are given in Fig 4l. Frequently the temperature of the city water main supply is low enough during the summer to permit an ap preciable cooling effect. Table 1 lists the maximum city water main temperatures for various localities in the United States and Canada. Air washers using refrigerated spray generally have their own recircu lating pumps. These pumps deliver to the sprays a mixture of water from the washer sump, which has not been re-cooled, and refrigerated water. The quantities of each are controlled by a three-way or mixing valve actuated by a dew-point thermostat located in the washer air outlet. ATMOSPHERIC WATER COOLING EQUIPMENT In the operation of a refrigerating plant or a condensing turbine, one of the main problems is the removal and dissipation of heat from the compressed refrigerant or the discharged steam. This is accomplished ordinarily by first transferring the heat of the gas to water in a heat exchanger, from which water it may then be dissipated in a number of ways. If the plant is situated on the banks of a river or lake, an intake may be taken up-stream or at a considerable distance from the discharge, to prevent mixing of the heated discharged water with the inlet water. If the source of cooling water is a city supply or a well, the discharge . water may be run into the nearest sewer or open waterway. Lacking an unlimited water supply, or in cases where city water is too expensive `Temperature of Water Available for Industrial Use in the United States, by W D Collins (U S Geological Surrey. Water Supply Paper No. 520 F). y' 'u- HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 1. Average Maximum Water Main Temperatures3 State ClTT Temp. State Cm Temp. Ala............. Birmingham________ Mobile......................... Ariz_______ Phoenix. -....... -....... rnlif Tucson........................ Berkeley..................... Fresno.- .................... Fullerton.. ........ . Glendale..................... Los Angeles............... Oakland...................... Ontario....................... Pasadena.................... Pomona...................... Riverside.................... Sacramento............... San Bernardino........ San Diego.... .............. San Francisco!.......... Whittier..................... Colo---------- Denver........................ Conn.____ Bridgeport................. Hartford--.................. New Haven............... Waterbury.~.l........... D. C--------- Washington............... t>pi Fla________ Jacksonville............... Miami......................... Tampa....................... . Ga________ Atlanta....................... Macon....... ...... .......... III._....... ..... Chicago.-- ................ Evanston...... ............ Peoria......................... Rockford........... !...!... Springfield.......--..... Ind....A.-- Evansville.----- ------Gary............................ Indianapolis. ........... South Bend.............. : Terre Haute. ........... Iowa.-........ Cedar Rapids. .--. Des Moines............ . Sioux City.................. Kans.._....... Concordia................... Kansas City.............. Topeka..................... Wichita.... .................. 84 73 81 80 60 69 72 75 68 75 69 70 82 75 78 72 65 82 62 75 75 66 73 76 72 84 83 80 80 77 87 80 76 76 . 73 67 59 82 86 75 80 61 82 78 77 62 .57 86 88 72 Ky. ........ 85 La--........... Baton Rouge............ New Orleans...... ...... 85 85 Me.............. 60 Mri 75 Cambridge............. Fall River. ............ Lowell. ...................... Lynn!.......................... New Bedtord............ Salem.......................... Worcester.-------------- Flint........................ Grand Rapids........... Highland Park.____ Jackson--................ -- Kalamazoo........... _... Lansing--......... ..... ..... Saginaw...!................. Minn-------- Duluth........... .......... Minneapolis.............. St. Paul-- ------------- Mo........... :. Jefferson City......... Kansas City......... St. Joseph--------------- St. Louis.--............... Springfield ,,__ Nebr.--.--: Lincoln....................... Omaha_____________ Nev... ......... Reno......... ................ N. H..-.:..... Manchester............... J.L..... Newark..... ................. Paterson..................... Trenton........ .............. N. Y--...... Albany----- -------------- Buffalo-..................... Jamaica___ '___ ___ ;.. Mt. Vernon............... New Rochelle._-.l_l.. New York. ...__ ; Rochester________ .... Schenectady--........... Syracuse......... ........... Utica----- ----....... Yonkers...................... N. C..-i... Asheville. ................ Charlotte.-:.--.____ Winston-Salem........ N. M......:.. Albuquerque..... '.___ Canton______ _____ _ Cincinnati. ______ Cleveland.................. Columbus.................. Dayton....................... Lakewood.................. Springfield____ _____ Toledo. _ ............ 80 70 76 50 68 70 68 76 77 70 84 77 56 53 64 82 55 80 77 82 84 84 85 70 87 87 61 76 63 74 78 79 68 75 56 74 75 72 70 60 74 69 70 74 85 82 65 76 50 84 74 82 60 82 72 83 These averages taken from various city water main locations, with some actual values slightly higher. and some lower than values shown. . 494 CHAPTER 26. SPRAY EQUIPMENT Table 1. Average Maximum Water Main Temperature3 (Concluded) State ClTT . FTemp. State ClTT FTemp. Pa ..... Erie McKeesport.............. Philadelphia:_______ Pittsburgh..... ;.l........ R. I. --.TM. Providence................ s! c........... SpartanburgTM........... S Dak.:.... Knoxville............... Nashville................. Austin-.... .............. Beaumont. ........... . Wichita Falla..____ 82 85 60 64 74 75 74 82 83 67 68 80 81 78 55 84 89 70 90: 65 90 86 86 84 90 84 83 76 '85 Utah......... Va............... r Wash......... a. Tacoma. W. Va.. ... Wis............ 44 60 **------- 75 73 80 58 62 51 ................ 57 85 78 78 54 58 70 68 Province Alta........... B. C.......... Ont............ P. E. I...... Que------- ... Quebec........................ 64 60 50 63 48 78 68 These averages taken from various'dty water main locations, with some actual values slightly higher and some lower than values shown. . ' or where the water available contains dissolved salts which would form scale on the heat-exchanging apparatus, it is necessary to recirculate the water, and to cool it after each passage through the heat-exchanger by exposure to air in an atmospheric water cooling apparatus. Air has a capacity for absorbing heat from water when the wet-bulb temperature of the air is lower than the temperature of the water with which it is in contact. The rapidity with which this transfer of heat occurs depends upon (1) the area of water in contact with the air, (2) the relative velocity of the air and water, and (3) the difference between the wet-bulb temperature of the air and the temperature of the water. Because the changes in rate do not occur in direct proportion to changes in the govern ing factors, data on the performance of atmospheric water cooling equip ment are largely empirical. As the heat content of the air increases, its wet-bulb temperature rises. (See Chapter 1.) Because it is impractical to leave the air in contact with water for a long enough time to permit the wet-bulb temperature of the air and the temperature of the water to reach equilibrium, atmos pheric water cooling equipment aims to circulate only enough air to cool the water to the desired temperature with the least possible expenditure of power. . In an air washer, humidifier or dehumidifier, the air is first conditioned 495 r HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 496 F ig . 4. A p p r o x im a t e W e l l W a t e r e m p e r a t u r e s a t D e p t h s o f 30 toT CHAPTER 26. SPRAY EQUIPMENT by water to change its moisture and temperature, and it is then sent to the place where it is to be used. In water cooling equipment the tem perature of the water is reduced by air, and the cooled water is carried to its point of usage. In the air washer, an excess of water is used to con dition a fixed quantity of air, while in water cooling equipment, an excess quantity of air is used to cool a fixed quantity of water. Both types of equipment have a common basis of design, however, in that the size of the equipment is determined by the quantity of air that must be handled. With the air washer, the size of the equipment is fixed by the quantity of air to be conditioned, and the amount of conditioning is controlled by the quantity and temperature of the water supplied and its method of application. With water cooling apparatus, its size and the quantity of air required bear no direct relation to the quantity of water being cooled, but vary through a wide range for different services and conditions. Sizes of Equipment Assuming a definite quantity of water to be cooled, the size and design of atmospheric cooling equipment are affected by the following factors: 1. Temperature range through which the water must be cooled. 2. Number of degrees above the wet-bulb temperature of the entering air to which the water temperature must be reduced. 3. Temperature of the atmospheric wet-bulb at which the required cooling must be performed. 4. Time of contact of the air with the water. (This involves height or length of the apparatus and velocity of air.) . 5. Surface of water exposed to each unit quantity of air. 6. Relative velocity of air and water. Items 1, 2, and 3 are established by the type of service and geographical location, while items 4, 5, and 6 depend upon the design of the equipment. The establishment of a proper cooling range depends upon: 1. Type of service (refrigerating, internal combustion engine and steam condensing). 2. Wet-bulb temperature at which the equipment must operate satisfactorily. 3. Type of condenser or heat-exchanger used. Because the design of an entire plant is usually affected by the quantity and temperature of the cooling water supply, plants should be designed for cooling water conditions which can be most efficiently attained. The first consideration is usually the limiting temperature of the plant. For. example, if an ammonia compressor refrigerating plant is to be designed for 185 lb head pressure as a normal maximum, the limiting temperature of the ammonia in the condenser is 96 F. Should the ammonia tempera ture go above this figure the head pressure will exceed 185 lb and power, consumption increases. To obtain this head pressure, the temperature of the circulating water leaving the condenser must always be less than 96 F by an amount depending upon the size and design of the condenser, the quantity of water being circulated, and the refrigerating tonnage being produced. A condenser having a large surface per ton of refrigeration may be designed to operate satisfactorily with the leaving hot water temperature within 3 or 4 F of the ammonia temperature corresponding 497 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Table 2. Condenser Design Data Gas Maximum Pressure Desired in Condenser Gas Temperature in Condenser Deg F DoF Best Condenser Design Average Condenser Design Ammonia........... 185 lb gage head pressure...... Carbon dioxide.. 1030 lb gage head pressure...... Methyl 102 lb gage Dichlorodi- 117 lb gage fluoromethane head pressure...... 101.2 115.1 125.9 96.0 86.0 100.0 100.0 97 110 120 92 83 96 96 93 105 114 88 81 . 92 93 to the head pressure, while a small condenser might require a 10 F difference. Table 2 lists several gases with data as to the temperatures and pres sures for which commercial condensers are designed/ Internal combustion engines have limiting hot water temperatures of 125 F to 140 F. The cooling of such fluids as milk or wort has variable requirements and is usually done in counter-flow heat-exchangers in which the leaving circu-. lating water is at a much higher temperature than is the leaving fluid. The temperature range, once the hot water temperature is approxi mately known, depends upon: 1. Maximum wet-bulb temperature at which the full quantity of heat must be dissipated. 2. Efficiency of the atmospheric cooling equipment considered. Design Wet-Bulb Temperatures . The maximum wet-bulb temperature at which the full quantity of water must be cooled through the entire range is never, in commercial design, the maximum wet-bulb temperature ever known to exist at the location nor the average wet-bulb temperature over any period. The former basis would require atmospheric cooling equipment several times greater than normal size, and the latter would-result during a large part of the time, in higher condenser water temperatures than those for which the plant was designed. For instance, the maximum wet-bulb temperature recorded in New York City is 88 F, and the July noon average for 64 years is close to 68 F. Yet in the years 1925 to 1934, inclusive, there were but 8 hours per year when the wet-bulb temperature reached 80 F or more, and there were 975 hours in the average summer (June to September inclusive) when the wet-bulb temperature was 68 F or above. As these 975 hours represent a third of the summer period, cooling equipment based upon the noon average J uly wet-bulb of 68 F would be inadequate. Commercial practice is to choose a wet-bulb temperature for refrigeration design purposes which is not exceeded during more than 5 to 8 per cent of the summer hours (75 F for New York City), with somewhat lower requirements for steam turbines and internal combustion engines. This 498 CHAPTER 26. SPRAY EQUIPMENT difference is made because the heaviest load on a refrigerating plant is coincident with high wet-bulb temperatures, whereas the heaviest electric power demand occurs either in the winter or after nightfall in summer, when the wet-bulb temperature is low. Table 1, Chapter 8, shows design wet-bulb temperatures which will not be exceeded more than 8 per cent of the time in an average summer. Knowing the hot water temperature and the wet-bulb temperature for which the equipment must be designed, the cold water temperature must be chosen to place the requirement within the efficiency range of the type of atmospheric water cooling apparatus to be used. Efficiency of atmos pheric water cooling apparatus is expressed as the percentage ratio of the actual cooling range to the possible cooling range. Since the wet-bulb temperature of the entering air is the lowest temperature to which the water could possibly be cooled this is: Percentage cooling efficiency of atmospheric water cooling equipment = (hot water temperature -- cold water temperature ) X 100 hot water temperature -- wet-bulb temperature of entering air Efficiencies of various types of atmospheric water cooling apparatus vary through wide limits, depending upon air velocity, concentration of water per square foot of area, and the type of equipment. The commercial range of efficiencies is given in Table 3 although unusual designs may operate outside these ranges. . From consideration of the factors which include the cooling range and design wet-bulb temperature, the quantity of water required can be calculated from the amount of heat to be dissipated. The normal amounts of heat to be removed from various processes of the cooling equipment are: Compressor refrigeration 220 to 270 Btu per minute per ton. Condenser turbine.^........... .......................... 950 to 980 Btu per pound of steam. Steam jet refrigerating apparatus1030 to 1150 Btu per pound of steam. Diesel engine...... ........... ............. ............ .....2800 to 4500 Btu per horsepower. Cooling Ponds A natural pond is often used as a source of condensing water. The hot water should be discharged close to the surface at the shore line. Natural air movement over the surface of the water will cause evaporation and carry away heat. Because increased density due to the loss of heat causes the cooled water to sink to the bottom of the pond, the suction Table 3. Efficiency of Atmospheric Water Cooling Equipment Equipment Natural Draft Deck or Atmospheric Cooling Eppicienct--Per Cent Minimum Usual Maximum 30 45 to 55 40 60 60 35 50 to 70 90 35 55 to 75 90 499 r HEATING VENTILATING AIR CONDITIONING GUIDE 1940 connection for intake water should be placed as far below the surface as possible, and at as great a distance from the discharge as practicable. Spray Cooling Ponds The spray pond consists of a basin, above which nozzles are located to spray water up into the air. Properly designed spray nozzles break up the water into small drops, but not into a mist because the individual drops must be heavy enough to fall back into the basin and not drift away with the air movement. The water surface exposed to the air for cooling is the combined area of all the small drops. Since the rate of heat removal by atmospheric water cooling is a function of the area of water exposed to the air, the difference in temperature between the water and the wet- bulb temperature of the air, the relative velocity of air and water, and the duration of contact of the air with the water, a much larger quantity of heat may be dissipated in a given area with the spray pond than with the cooling pond, because of (1) the speed with which the drops travel as they are propelled into the air and fall back into the water basin, (2) the increased wind velocity at a point above the surrounding structures or terrain, (3) the increased volume of air used, and (4) the vastly increased area of contact between air and water. Spray pond efficiencies are increased by (1) elevating the nozzles to a higher point above the surface of the water in the basin, (2) increasing the spacing between nozzles of any one capacity, (3) using smaller capacity nozzles to decrease the concentration of water per unit area, and (4) using smaller nozzles and increasing the pressure to maintain the same concentration of water per unit area. Usual practice is to locate the nozzles from 3 to 7 ft above the edge of the basin, to supply from 5 to 12 lb pressure at the nozzles, using nozzles spraying from 20 gpm to 60 gpm each and spacing them so the average water delivered to the surface of the pond is from 0.1 gpm per square foot in a small pond to 0.8 gpm per square foot in a large pond. Increasing the pressure, spacing the nozzles farther apart, or increasing the elevation of the nozzles will increase the cross-section of spray cloud exposed to the air, and therefore increase the quantity of air coming in contact with the water. Best results are obtained by placing the nozzles in a long relatively narrow area located broadside to the wind. . Spray ponds may be located on the ground, or they may be placed on roofs. To prevent excessive drift loss, or the carrying of entrained water beyond the edge of the pond by the air on the leeward side, louver fences are required for roof locations and for those ground locations where space is so restricted that the outer nozzlesr.cannot be located at least 20 ft to 25 ft from the edge of the basin. Such fences usually are con structed of horizontal louvers overlapping so the air is forced to turn a comer in passing through the fence, and the heavier drops of water are. thrown back, owing to their inertia. The louvers also restrict the flow of air, particularly at the higher wind velocities, and thus further reduce the possibility of water being carried off. The height of an effective fence should be equal to the height of the spray cloud. Louver boards are preferably of red gulf cypress or California redwood supported on cast- iron, steel or wood posts. Where building ordinances forbid the use of combustible materials, sheet metal is customarily used. " . 500 CHAPTER 26. SPRAY EQUIPMENT Algae growths, during warm weather, in cooling towers and spray ponds may be eliminated while the plant is in operation by the use of potassium permanganate. This chemical can be dissolved at the rate of 1 lb in 1J4 to lH gal of hot water. About 10 parts of permanganate should be used per million parts of cooling water. The permanganate attacks the algae, forms a brown covering over it, and causes it to settle. Enough of the permanganate solution should be added periodically to cause the water to have a pink color for a period of from 15 to 20 min. Small additions of the permanganate daily do not give concentrations which are effective. The best results are obtained when sufficient quantities are added periodically at intervals of several weeks,-the time intervals being dependent upon local operating conditions. The chemical is non-poisonous and is non-corrosive when used as directed. Spray Cooling Towers Where not more than 30,000 Btu per minute are to be dissipated, the spray cooling tower is a satisfactory apparatus. The word lower in this connection is somewhat of a misnomer as the apparatus is essentially a narrow spray pond with a high louver fence. As usually built, the nozzles spray down from the top of the structure and the distance from the center of the nozzle system to the fence on either side is not more than half the distance that the nozzles are elevated above the water basin. Heights range from 6 ft to 15 ft and the total width of a structure is not usually greater than its height. Spray, cooling towers occupy less space on small jobs than spray ponds of equivalent capacities because the towers have a capacity of from 0.6 gpm to 1.5'gpm per square foot of tower area. The louvers are continually wet, and so add to the surface of water exposed to the cooling air. . Natural Draft Deck Type Towers In past years most of the atmospheric water cooling on refrigeration work has been done with natural draft deck type towers, which are also referred to as wind or atmospheric towers. These towers consist of heavy wooden or steel framework from 15 to 80 ft high and from 6 to 30 ft wide, having open horizontal lattice-work platforms or decks at regular intervals from top to bottom, and a catch basin at the foot. The hot water is distributed over the upper part of the'structure by means of troughs, splash heads, or nozzles, and it drips from deck to deck down to the basin. The object of the decks is to arrest the fall of the water so as to present efficient cooling surfaces to the air, which passes through the tower parallel to the decks. The decks also add to the area of water surface exposed to the air, but since they furnish a resistance to air flow, too many decks are a detriment. To prevent the loss of water on the leeward side of the tower, wide splash boards are attached at regular intervals from top to bottom. These boards or louvers extend outward and upward, and in most designs the top edge of each louver extends above the bottom edge of the one above it. Efficiency of a deck tower is improved, within limits, by increased height, increased length, or increased width. The first two increase the area of water exposed to the wind, and the latter increases the time of contact of the air with the water. 501 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Wind Velocities on Natural Draft Equipment Since natural air movement is the prime requirement for a deck type tower, spray cooling tower, or spray pond, the apparatus must be de signed to produce the desired cooling on days when the wind velocity is below average when the wet-bulb temperature is at the maximum chosen for design, and when the plant is operating at full load. The apparatus must also, for best results, be located with its longest axis at right angles to the direction of the prevailing hot weather breeze. Table 1, Chapter 8, gives the average summer wind velocities and directions in representative cities. Natural draft cooling equipment should be designed to operate properly with not more than one-half of the average wind velocity, and in no case for a wind velocity of more than 5 mph. It is obvious that natural draft towers and other natural draft equipment must be so located that they are not obstructed by trees, buildings, or other wind deflectors. , V Mechanical Draft Towers Mechanical draft towers usually consist of vertical shells, constructed of wood, metal, or masonry, in which water is distributed uniformly at the top and falls to a collecting basin at the bottom. The inside of the tower may be filled with wood checker-work over which the water drips, or the water surface may be presented to the air by filling the entire inside of the structure with spray from nozzles. Air is circulated through the tower from bottom to top by forced or induced draft fans. Since the air flows counter to the water, the air is in contact with the hottest of the water just before leaving the top of the tower, and each unit of air picks up more heat than a similar unit would on natural draft equipment, so the me chanical draft tower cools water by using less air than the other types of equipment need. As movement of the air through the towers is obtained by power-consuming fans, it is essential that the air used be reduced to a minimum so as to secure the lowest possible operating cost. The efficiency of a mechanical draft tower is increased by increasing height, area, or air quantity. Increasing the height increases the length of time the air is in contact with the water without affecting seriously the fan power required, but it increases the pumping power needed. In creasing the area while maintaining constant fan power increases the air quantity somewhat and because of lowered velocities it increases the time this air is in contact with the water. The surface area of water in contact with the air is increased in both cases. Increasing the air quantity decreases the time the air is in contact with the water, but, since a greater quantity is passing through, the average differential between the water temperature and the wet-bulb temperature of the air is increased, and this speeds up the heat transfer rate. Increased air quantities are obtained only at the expense of increased fan power, which increases approximately as the cube of the air quantity. Air velocities through mechanical draft towers vary from 250 to 600 fpm over the gross area of the structure. Mechanical draft water cooling equipment may be set up inside build ings, where it usually draws its air supply from the general space in which it is installed, and discharges its exhaust air through a duct to the outside. Indoor cooling towers may be either of the wood-filled or the spray-filled type. In many cases where little height but considerable area is available, 502 CHAPTER 26. SPRAY EQUIPMENT water is cooled in a spray-filled structure similar to an air washer, with the air passing horizontally through the apparatus and being discharged through a duct to the outside. Such apparatus does not have the counter flow advantage of the vertical mechanical draft water cooling equipment, and therefore requires a much larger excess of air for proper operation. Air velocities and operating powers are considerably above those required by vertical mechanical draft water cooling equipment. Make-Up Water Since the atmospheric water cooling equipment performs its functions chiefly by evaporating a portion of the water in order to cool the re mainder, there is a continual drain on the quantity of water in the system, and this loss must be replaced. Approximately 1 gal of water is lost for every 1000 gal of water cooled per degree of cooling range; so if 1000 gpm of water are cooled through a 10 F range, 10 gpm of water will be re quired to replace evaporated water. Replacement supply is usually Table 4. Comparison of Various Types of Atmospheric Water Cooling Equipment Figures indicate order of desirability Coouna Sprat Pond Pond Cost.... .................................................................. Area.- .............................................................. Height. ............................................................ Weight per square foot... ............................. Independence of wind velocity..................... Drift nuisance....... -........................................... Make-up water required. ............................. Pumping head..... ......................................... Maintenance................ ................ ..................... Suitability for congested districts................ Water quantity required for definite result.. ......................... ................................ X 5 1 X 6 1 1 1 2 X 6 2 4 2 X 3 6 6 2 1 5 5 Sprat Decs Mechanical Indoor Tower Tower Draft Tower i 3, 4 3 2, 1 3 4-5. 4-5 1 3. 4 45 1-2 54 2-3 54 2-3 3 4-5 4-5 34 5 43 1 5 X X 2 1-2 2-3 2-3 6 6 2 4 1-2 1-2 3 *Not comparable. regulated by a float control valve. Because the evaporation of the water leaves behind the salts which the water contained, high concentration of salts may make chemical treatment of the make-up water necessary to avoid excessive deposits in the condensers. An additional amount of make-up water must be added to replace windage, or drift loss. This additional amount of water varies from 0.1 to 3 per cent of the quantity of water being circulated, this percentage depending upon the type of equipment and the wind velocity. Winter Freezing If atmospheric water cooling equipment is operated in freezing weather, the water may be cooled below freezing temperature so ice forms and collects until its weight causes damage. To obviate freezing during con tinued operation, the efficiency of the apparatus may be lowered. This is done on the spray pond and the spray cooling tower by reducing the quantity of water fed to the apparatus, thereby lowering the pressure at the nozzles and increasing the size of the drops produced. On the deck tower the upper system may be shut off and a secondary distribution 503 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 system put in service midway down the height of the tower. The water will be kept above freezing because it will have shorter contact with the air. The mechanical draft tower can be protected by reducing the air flow through the tower, by stopping or reducing the speed of the fans, or by partially closing dampers. If the system is operated intermittently in freezing weather, water in the basin may freeze and the expansion of the ice may do harm. Freezing during intermittent operation can be prevented only by draining the water basin when it is out of service. On small roof installations, a tank large enough to hold all the water in the system is often installed inside the building and the basin is drained into this by gravity, the pump suc tion being taken from this inside tank. A comparison of various types of water cooling equipment is given in Table 4. ' Chapter 27 AIR CLEANING DEVICES Damage Caused by Dust, Classification of Air Cleaning Devices, Viscous-Impingement Filters, Dry Air Filters, Air Washers, Electrical Precipitators, Cleaning of Cases from Exhaust Systems IN. this chapter the term cleaning is assumed to mean the removal of particulate matter from the air. The removal of foreign gases and vapors requires entirely different methods and is discussed in Chapter 35. The cleaning of air involves the removal of many kinds of materials having a wide range of particle sizes and concentrations. The degree of air purification required varies widely, consequently, many types of devices having radically different design characteristics are available. The various materials that pollute the air are discussed in Chapter 4, Fig. 1, which shows characteristics of particles ranging in size from 8000 to 0:001 microns. The importance of particles in the range from 0.1 to 0.001 microns is open to argument. Particles below 0.1 micron can be seen in some microscopes as specks of reflected light, and a few micro scopes using ultra-violet light have a resolving power of 0.1 micron, but the smallest particle which is really resolved in microscopes using ordinary light is about 0.25 micron. The performance of particles below 0.1 micron is, therefore, controversial because no means have been developed for reliably counting or measuring the sizes of the particles. . Even if the discussion is limited to the range from 0.1 micron to 50 microns, from the smallest particle observable in the microscope to the smallest particle distinguishable to the naked eye, this range is so far outside the usual experience that it is difficult to visualize. If particles could be examined through a super microscope having a magnification of 250,000 diameters, a tobacco smoke particle of 0.1 micron would appear to be 1 in. in diameter, or approximately the size of a golf ball; a soft coal smoke particle 0.3 micron in diameter would appear like a baseball; a ragweed pollen grain 20 microns in diameter would appear 16J^ ft in diameter, while the 50 micron particle, just visible to the naked eye and able to pass through a 270 mesh screen, would appear to be 50 ft. in diameter. Picturing this range in particle size from a golf ball to a sphere 50 ft in diameter may aid in appreciating the problem of cleaning air and the difficulty of devising any single test to adequately measure the performance of air cleaning devices under all conditions of service. 505 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 DAMAGE CAUSED BY DUST Dust may cause damage in many ways, but usually. it must first lodge on a surface. Larger particles settle rapidly out onto surfaces. The rate of fall of particles is given in Chapter 4, Fig. 1. Those visible to the unaided eye (50 microns or over) fall so rapidly that few:remain in the air. However, any large ones which are carried into a room are almost certain to settle and are so noticeable when they have settled as to be very objectionable. Any air movement, particularly over fabrics or unpolished surfaces, tends to deposit dust on the surface. The smallest particles observable in the microscope are deposited in this way. A phenomenon of great importance in air conditioning and one not yet generally appreciated is thermal precipitation of dust. This is the tendency for dust to be deposited on any surface which is cooler than the adjacent aii\ It is largely responsible for outside walls becoming dirtier than partitions. In the case of plaster on wood lath, the dark streaks following the spaces between laths are very noticeable and frequently beams and other structural members can be traced by the difference in blackness of the wall or ceiling. Thermal precipitation deposits particles of all sizes apparently with very little differentiation as to size. By keeping the surface temperature higher and more uniform, modern thermal insulation decreases the deposit of dust and makes it more uni form and less noticeable. REQUIREMENTS The removal of larger particles is always important because they quickly settle out of the air and become noticeable on surfaces as visible dustiness. In many applications the removal of these larger particles will constitute satisfactory performance, and a relatively simple device can be used. _ In cities where large quantities of soft coal are burned, the air becomes contaminated with fine black smoke particles. These are deposited on walls, draperies, and other interior surfaces by air movement and by thermal precipitation. Their removal is much more difficult than that of the large particles. Hay fever is usually due to pollen in the air, and many people, once this trouble has started, are sensitive to minute amounts of pollen, so that almost perfect cleaning may be required. Asthma many be caused by many things, including pollens and fine dusts. Many afflicted with either disease, who have not obtained relief from usual remedies, have found it in a room where the air is efficiently cleaned from small as wel| as large particles. In air conditioning systems the maintenance of constant air flow is essential. In summer cooling, a decrease in air flow may cause a reduction in temperature of discharged air. This, combined with reduced velocity, may completely upset the air distribution objective resulting in drafts. The air cleaning equipment must function so that reduction in air flow due to. the normal accumulation of dust will not cause faulty operation of the system. 506 CHAPTER 27. AIR CLEANING DEVICES In addition to requirements which are specified the following features are desirable: 1. Low resistance to air flow. 2. Ease of cleaning and maintenance. 3. Efficiency over a wide range of velocities. 4. Binding liquid to catch particles must not contaminate the air. TESTING The wide variety of materials and particle sizes which may be present in the air makes the testing of air cleaning devices difficult. Probably no standardized test can cover all of the conditions which may be en countered in service. Tests have been devised which compare the ability of air cleaners to remove a certain artificial dust under specified conditions. This seems to be the most practical way of comparing various devices, but it may lead to misleading results if the dust is not representative of the dust to be removed in service. The most common test is that specified by the A.S.H.V.E. Standard Code for Testing and Rating Air Cleaning Devices Used in General Ventilation Work1. This Code specifies an artificial dust consisting of a mixture of dusts, which has passed through a 200 mesh screen. The efficiency is measured in terms of the ratio of the weight of dust removed to the weight of dust injected into the air. This is a well-worked-out method for testing the ability of a device to remove the coarser particles, but it is not a satisfactory measure of the ability of a device to remove extremely fine particles. In general, any weight method tends to measure the efficiency of removal of the larger particles present in the test dust. The largest particle specified in this Code is one just passing a 200 mesh screen or one 70 microns in diameter. Assuming a dust containing one such particle to 1,000,000 particles having a diameter of 0.1 micron, the 70 micron particle will have 3.43 x 108 times the weight of one of the 0.1 micron particles, all particles having the same density. If the cleaning device removes the one large particle but removes none of the 0.1 micron particles, the weight efficiency will be the ratio of the weight removed to the weight of dust injected or 99.71 per cent by weight even though only one particle out of 1,000,000 has been removed. This is obviously an exaggerated case, but illustrates the weakness of a weight test in meas uring efficiency of removal of fine particles. . In testing air filters at the National Bureau of Standards, a much finer dust is used and the efficiency is measured by determining the relative blackness of pieces of filter paper through which air is passed2. The test dust used is a sample of dust collected by a precipitator in a local power plant, which of is course not as fine as atmospheric dust. However, this method of measuring efficiency can be used with atmospheric dust to test an air cleaning device under actual operating conditions. The efficiency is determined by drawing samples of filtered and unfiltered air through pieces of filter paper, the volumes of air being adjusted until ... Standard Code for Testing and Rating Air Cleaning-Devices Used in General Ventilation Work (A.S.H.V.E. Transactions, Voi. 39. 1933. p. 225). . =A Test Method for Air Filters, by Richard S. Dill (A.S.H.V.E. Transactions, Vbl. 44, 1938, p. 379). 507 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 equal blackness is obtained. If, for example, one unit of volume of unfiltered air gives the same blackness as four units of volume of filtered air, the efficiency is said to be 75 per cent. This method gives a much better measure of the tendency to blacken walls than the weight ef ficiency. # CLASSIFICATION OF AIR CLEANING DEVICES Considering the wide variety of materials and particle sizes to be removed, and the variety of requirements it is natural that many kinds of devices are used which cannot be shown satisfactorily in' a single simple classification. The following outline gives classifications on three different bases: ' 1. Methods of cleaning. a. Automatic. b. Non-automatic. (1) Throw-away, replaceable elements. (2) Manually cleaned in place. (3) Removable for cleaning. . 2. Principle of air cleaning. a. Viscous-impingement filters. b. Dry filters. c. Washers; . d. Centrifugal devices. e. Electrical precipitators. 3. Classification according to application. a. General air conditioning. (1) Central cleaning system. (2) Unit ventilator. (3) Window installation. (4) Warm air furnace. b. Removabof smoke and fumes from stack gases. c. Collection of dusts from exhaust systems. '' VISCOUS IMPINGEMENT TYPE FILTERS . The principle of air cleaning used, in viscous filters is that of adhesive impingement. Dust and dirt in the air, especially soot and carbons, are trapped and retained by successive impingements on coated surfaces. The arrangements of filtering mediums and the kind of materials used are almost unlimited. Since this type of device depends on impingement, it is more effective in catching large particles than small ones. To secure maximum cleaning efficiency, it is necessary to divide the air into in numerable fine streams, to obtain intimate contact between the air and the viscous-coated mediums. The following are desirable characteristics of a binding liquid: 1. Its surface tension should be such as to produce a homogeneous film-like coating on the filter medium. 2. The viscosity should vary only slightly with normal changes of temperature. 3. It should prevent the development of mold spores and bacteria on the filter mediums. 508 CHAPTER 27. AIR CLEANING DEVICES 4. The liquid should have high capillarity, or ability to wet and retain the dust at all operating temperatures. 5. Evaporation should be low. 6. It should be fire resistant. 7. It should be odorless. Viscous Type Unit Filters In the unit type viscous filter, the filtering mediums are arranged in units of convenient size to facilitate installation, maintenance, and cleaning. Each unit consists of an interchangeable cell or replaceable filter pad and a substantial frame which may be bolted to the frames of other like units to form a partition between the so.urce of dusty air and the fan inlet. To secure the maximum dust-holding capacity, the filter medium is usually arranged with large pores or air passages on the entering air side, . the filter density increasing gradually toward the leaving air side. This arrangement provides relatively large spaces for the collection of dirt in QUANTITY OF OUST. OUNCES . Fig. 1. Chart Showing Change in Resistance Due to Dust Accumulation the front of the filter where the bulk of the dust is taken out without undue increase in resistance, while in the back of the filter the openings are smaller to secure high efficiency in the removal of the finer dust particles. The. resistance of a well-designed unit filter of the adhesive impinge ment type usually depends upon the velocity at which the air is. handled and upon whether the unit is clean or dirty. The cleaning efficiency is usually highest after it has accumulated a certain portion of its maximum load of dirt because some dust collected in the cell acts as an efficient medium for the further seizing of solids from the air. By periodically cleaning a predetermined number of cells, the resistance and capacity of a built-up filter may be held at any desired figure. The frequency of cleaning any installation depends upon the dust concentration of air being cleaned, and on the amount of dirt which can be accumulated in the medium without causing excessive resistance. (Figs. 1, 2 and 3.) The dust-holding capacity of a given filter is dependent on the type of dust. Lint is particularly difficult to collect because it tends to build up a layer over the face of the filter. In this way a small quantity of dust may cause a serious increase in the pressure drop of a filter. A chart showing the increase in resistance of a unit filter of the viscous impingement type, when tested with the standard test dust described in 509 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 the Code, is given in Fig. 1. The resistance to air flow of three typical clean viscous impingement type filters having different densities of mediums is shown in Fig. 2. Type A is a dense pack used in bacterium control; Type B is a medium pack used for general ventilation work, and Type C is a low resistance unit for use where low resistance is the important factor and maximum cleaning efficiencies are not essential. The operating characteristics which might be expected under various dust concentrations with air filters having different dust-holding capacities are illustrated in Fig. 3. Filters consisting of inexpensive frames of cardboard or similar material filled with viscous-coated glass wool, steel wool or the like are available. Because of their construction these units may be discarded when dirty' and replaced with new units at relatively little expense. They are used in general ventilation work and with warm-air furnaces and other instal- CHAPTER 27. AIR CLEANINC DEVICES The washing and renewing process in automatic filters of the second and third types is usually intermittent. It is accomplished by an electric motor or by other motive power and is controlled by manual or by auto matic timing devices. The operating cycle is of a predetermined frequency and should be so timed as to insure a constant static pressure drop across the filter. The customary resistance to air flow is j^-in. water gage at an air velocity of 500 fpm, measured at the filter entrance. Automatic . viscous filters are made up in units which are delivered either fully as sembled or in parts to be assembled at the point of installation. DRY AIR FILTERS Dry air filters, in. which dust is impinged upon or trapped in screens made of felt, cloth, cellulose, or other fabrics, are available in various types. These filters require no adhesive liquid, but depend on the strain- Ftc. 2. Resistance to Air Flow of Tvpical Unit Air Filters lations where low first cost and low resistance to air flow are essential. The operating characteristics of these units conform in general with those of the rigid frame type. - -. Viscous Automatic Filters In this type of filter, the removal of the accumulated dust is done automatically instead of by hand. The automatic cleaning and recoating of these filters is based on the principle that the viscous fluid itself will perform the cleaning function, thereby eliminating a separate washing agent. The dust collected by the filter is deposited finally in the bottom of the viscous fluid reservoir from which it may be removed by different methods, depending on the design of the filter. . There are three general types of automatic filters. They are differ entiated from each other according to the process of self-cleaning and renewing of the viscous coating used as follows: 1. The filter medium has the form of an endless curtain suspended vertically, with its lower portion submerged in a viscous fluid reservoir. The curtain moves slowly through this bath, thus performing the cleaning and recoating of the filter medium. 2. The filter screen is arranged in the form of shelves or cylinders, and the viscous fluid is flushed through all parts of the medium in a direction opposite to the air flow. 3. The filter medium is arranged vertically and is stationary. The viscous fluid is flushed from above over the medium, while the air flow is stopped. 510 , Fig. 3. Maintenance Chart for Unit Type Viscous Filters ing or screening action of the filtering medium. Because of the close texture of the materials used in most of the dry filters, the surface velocity, or velocity of the entering air, ranges between 10 and 50 fpm, depending on the nature and texture of the fabric. This necessitates a relatively large screen surface, which is usually arranged in the form of pockets to bring the frontal area within customary space requirements. As with viscous unit filters, an average constant resistance and air volume may be obtained by periodic reconditioning or renewal of the filter screens. Since some materials suitable for dry filtering. mediums are affected considerably by moisture which tends to cause a rapid increase in resistance, they should be treated or processed to minimize the effect of changes in humidity. Filters using felt and similar materials usually depend upon vacuum cleaning for reconditioning. A special nozzle, operated from a portable or stationary vacuum cleaner, is shaped to reach all parts of the filter pockets. Permanent filter mediums should be capable of withstanding repeated vacuum cleanings without loss in dust removal efficiency. While 511 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 most dry filters are cleaned by replacing an inexpensive filter sheet, the useful life of these sheets often may be lengthened by vibrating or vacuum cleaning. . AIR WASHERS Air washers, originally designed as the name implies to wash air, are now used, for humidification (see Chapter 26). Their ability to cleanse air depends upon the nature of the dust; fine particles,' especially those having no affinity for water, are not efficiently removed. ELECTRICAL PRECIPITATORS Electrostatic precipitation has long been used for the precipitation of' smokes and fumes from smoke stacks, but until recently such equipment was unsuited to air conditioning and ventilation applications. 'The , operating principles are as follows: A discharge takes place from a small wire to grounded electrodes and as the air passes through this discharge the dust particles receive an electrical charge. The air then passes between parallel plates with a high potential difference between plates. The resulting electric field attracts the dust particles to one set of plates. The electric force is effective in depositing the particle on the plate, but does not hold it there. Some dusts stick to the plates, but in general there should be a coating of adhesive. The dust is removed by washing. As this device is sensitive to air velocities, care should be taken to avoid any local currents that exceed rated velocity. An advantage of electro static precipitation is the ability to remove fine particles at high efficiency and with a low pressure drop, and thus with little change in the volume of air delivered. This feature must be balanced against the greater first cost. CLEANING OF GASES FROM EXHAUST SYSTEMS The gases from exhaust systems vary widely, but in general contain heavy, concentrations of dust as compared to ventilation practice. A dust loading of one grain per cubic foot of air is not unusual, which is about 1000 times the dirt usually found in ventilating air. For this reason even though the cleaning efficiency is high it is still usually desir able to discharge the exhaust out of doors. The purpose of the cleaning is then to prevent a nuisance in the neighborhood or to collect valuable material. Gravitational Settling Chambers Settling chambers are simple but effective only in removing large particles. The rate of fall of various particles is given in Fig. 1 of Chapter 4. Even though the vertical height is kept small to reduce the time of fall, limitations of space and volume of air to be handled usually allow time for only the larger particles to settle, even if the flow is perfectly streamline. Actually, eddies retard the settling of particles so that the full velocity of fall is not realized. Cyclones or Centrifugal Separators. The force causing settling can be increased many times that of gravi tation by giving the air a whirling motion and introducing centrifugal 512 CHAPTER 27. AIR CLEANING DEVICES force. The settling rate then becomes dependent upon the peripheral air velocity and the radius of curvature as well as upon the other factors. In cyclone separators, air is introduced tangentially into a vertical cylinder and passes out from the center of the top. The gas velocity and curvature of the cylinder cause whirling which throws the particles to the surface. The particles slide down this surface and are removed through a hopper in the cone bottom, or are thrown through slits in the periphery. '. Assumptions regarding streamline flow and turbulence make general calculations of centrifugal settling rate quite involved and rough. Cen trifugal separators have wide application in connection with industrial operations such as grinding, screening and combustion, but have little or no effect upon the finer particles. . When a high collection efficiency is desired, or the material is unusually fine, multicyclones may be used. These are merely small cyclones arranged in parallel which utilize the principle of high centrifugal velocity to attain separation. Cloth Filters Filters are used when the material collected by an exhaust system is valuable or cannot be separated efficiently from the air with an ordinary cyclone: They are also employed when it is desirable to recirculate the air drawn from a room by the exhaust system, which otherwise might entail considerable loss in heat. Bag filters which are properly housed may be operated under suction. Bag houses used in manufacture of zinc-oxide and other chemical products are operated on the positive side of the fan. Wool, , cotton and asbestos cloths are commonly used as filtering mediums. When woolen cloths are employed, the filtering capacities vary from x/l to 10 cfm per square foot of filtering surface, depending on the character of the material collected. The rates for cotton and asbestos cloths are. lower. The type of filter cloth and the rates of filtration depend, of course, oh the material to be collected and the fan capacity. The collected dust particles themselves aid in agglomerating and retaining others. Periodic shaking with the fans off or reversed, at intervals of a few hours drops the excess dust into a lower header or hopper for removal. Readily removed filters built in small sections in which filter mediums can be replaced are of distinct advantage where deterioration is rapid. Various styles of construction are available which combine quick inter changeability and large filtering area per square foot cross-sectional area. Use of several independent units in parallel is important for the recon-. ditioning of each unit separately. Both continuous and intermittent shaking and sweeping devices remove excess dust and maintain a low resistance. . Such filters should be frequently inspected for leaks and the bags or screens should be in readily replaceable units. General practice in this field is to use a low flow per square foot of cloth and a high pressure drop, giving a relatively high efficiency as compared to general ventilation practice. However, because of the high dust loading, the discharged air may still carry excessive dust for ventilating purposes. 513 F HEATING VENTILATING AIR CONDITIONING GUIDE 1940 SMOKE STACKS Gases discharged from smoke stacks may contain relatively large particles of cinders and carbon as well as the fine smoke which remains in relatively permanent suspension. Large particles settle quickly and are likely to constitute a serious nuisance in the immediate neighborhood. Smoke tends to spread over a large area, but in cities the large number of stacks may pollute the atmosphere over the entire city. A variety of cinder catchers are available for catching the large cinders. Devices of the cyclone type remove much finer particles, but for anything approaching complete cleaning, electrostatic precipitators are usually required. For this purpose they usually consist of wires (at. potential of 30,000 to 100,000 volts negative) suspended between vertical plates or hanging in the center of vertical cylinders. The dust collects on the plates or cylinders which are periodically vibrated for rapped to . cause the dust to fall down into hoppers. . REFERENCES Design and Application of Oil-Coated Air Filters, by H. C. Murphy (A.S.H.V.E. Transactions, Vol. 33, 1927, p. 73). Operation and Maintenance of Air Filters, by W. G. Frank {Heating, Piping and Air Conditioning, May, 1931, p. 378). Size and Characteristics of Air-Borne Impurities, by W. G. Frank {Heating, Piping and Air Conditioning, January, 1932, p. 35). Fundamental Principles in the Design of Dry Air Filters, by Otto Wechsberg (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, April, 1933, P- 217). Operation, Maintenance of Cloth-Screened Dust Collectors, by W. F. Terry (Heating,. Piping and Air Conditioning, May, p. 259, June, p. 304, 1933). Testing and Rating of Air Cleaning Devices Used in General Ventilation Work, by Samuel R. Lewis (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 277). Air Filter Performance as Affected by Kind of Dust, Rate of Dust Feed, and Air Velocity Through Filter, by F. B. Rowley and R. C. Jordan (A.S.H.V.E. Transactions, Vol. 44, 1938, p. 415). ` The Dust-Free Space Surrounding Hot Bodies, by H. H. Watson {Transactions of the Faraday Society, Vol. 32, 1936, Pt. 2, p. 1073). . A New Electrostatic Precipitator, by G. W. Penney {Electrical Engineering, January, 1937, p. 159). . 514 Chapter 28 FANS Classification, Performance, Fan Efficiency, Characteristic .Curves, System Characteristics, Selection of Fans, Volume Control, Fan Designations, Motive Power IN heating and ventilating practice, fans are used to produce air flow except where positive displacement is required, in which case com pressors or rotary blowers are used. Fans are classified according to the direction of air flow as (1) axial flow or propeller type if the flow is parallel with the axis, and (2) radial flow or centrifugal type if the flow is parallel with the radius of rotation. Axial flow fans are made with various numbers of blades of a variety of forms. The blades may be of uniform thickness (sheet metal), either flat or cambered, or may be of varying thickness of so-called aerofoil section (airplane propeller type). Where an axial flow fan is intended for operation at comparatively high pressures the hub sometimes is enlarged in the form of a disc and the fan is known as a disc fan. Radialflow or centrifugalfans include steel plate fans, pressure blowers, cone fans, and the so-called multiblade fans. All the foregoing types have variations which may be obtained by modification of the proportions or change, in the curvature and angularity of the blades. The angularity of the blades determines the operating characteristics of a fan; a forward curved blade is found in a fan having slow speed operating characteristics, while a backward curved blade is found in a fan having high speed operating characteristics. A wide variation exists in the demands which have to be met by fan installations. A fan may be required to move large quantities of air against little or no resistance or it may be required to move small quanti ties against high resistances. Between these two extremes innumerable specific requirements must be met. In general, fans of all types in each general class can be made to perform the same duty, although mechanical difficulties, noise or lack of efficiency may limit the .use to one or another type. The most common field of service for fans of the propeller type is in moving air against moderate resistances, especially where no long ducts or heavy friction must be overcome and where noise is not objectionable, whereas centrifugal fans are commonly employed for operation at the comparatively higher pressures and where extreme quietness is necessary. FAN PERFORMANCE Fans of all types follow certain laws of performance which are useful in determining the effect of changes in the conditions of operation. These 515 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 laws apply to installations comprising any type of fan, any given piping system and constant air density, and are as follows: 1. The air capacity varies directly as the fan speed. 2. The pressure (static, velocity, and total) varies as the square of the fan speed. 3. The power demand varies as the cube of the fan speed. Example 1. A certain fan delivers 12,000 cfm at a static pressure of 1 in. of water when operating at a speed of 400 rpm and requires an input of 4 hp. If in the same installation 15,000 cfm are desired, what will be the speed, static pressure, and power? Speed = 400 X = 500 rpm Static pressure = 1 X = 1.56 in. Power = 4X (^5)* = 7-81 hP When the density of the air varies the following laws apply: 4. At constant speed and capacity the pressure and power vary directly as the density. Example S. A certain fan delivers 12,000 cfm at 70 F and normal barometric pressure (density 0.07492 lb per cubic foot) at a static pressure of 1 in. of water when operating at 400 rpm, and requires 4 hp. If the air temperature is increased to 200 F (density 0.06015 lb) and the speed of the fan remains the same, what will be the static pressure and power? . Static pressure = 1 X ~q = 0-80 " Power = 4 X 0,06015 0.07492 = 3.20 hp 5. At constant pressure the speed, capacity and power vary inversely as the square root of the density. . Example S. If the speed of the fan of Example 2 is increased so as to produce a static pressure of 1 in. of water at the 200 F temperature, what will be the speed, capacity, and power? - Speed = 400 X = 446 rpm Capacity = 12,000 X J _-07jgg_ = 13,392 cfm (measured at 200 F) : y 0.06015 . Power = 4 X - 4.46 hp . 6. For a constant weight of air: . . (a). The speed, capacity, and pressure vary inversely as the density. (6) The horsepower varies inversely as the square of the density. Example 4- If the speed of the fan of the previous examples is increased so as to deliver the same weight of air at 200 F as at 70 F, what will be the speed, capacity, static pressure, and power? Speed = 400 X = 498 rpm Capacity = 12,000 X O q601^ = 14,945 cfm (measured at 200 F) CHAPTER 28. FANS ' .. , ,, 0.07492 , . Static pressure = 1 X 0 06015 = 1-25 ,n' Power = 4 X (S)2 = 6 20 hp FAN EFFICIENCY The efficiency of a fan may be defined as the ratio of the horsepower output to the horsepower input. The horsepower output is expressed by the formula: Air Horsepower1 cfm X total pressure in inches of water 6356 (1) When the static pressure is used in the computation it is assumed that this represents the useful pressure and that the velocity pressure is lost in the piping system and in the air which leaves the system. Since in most installations a higher velocity exists at the fan outlet than at the point of delivery into the atmosphere, some of the velocity pressure at the fan outlet may be utilized by conversion to static pressure within the system, but owing to the uncertainty of friction losses which occur at tlje places where changes in velocity take place, the amount of velocity pressure which is actually utilized is seldom known, and the static pressure alone may best represent the useful pressure. The efficiency based upon static pressure is known as the static efficiency and may be expressed as follows: ` Static efficiency1 = cfm X static pressure in inches of water 6356 X Horsepower input (2) Different fans may develop the same capacity against the same static pressure and with the same power input, and therefore operate at the same static efficiency, while maintaining different outlet velocities. Where a high outlet velocity is desirable or can be utilized effectively, the static efficiency fails to be a satisfactory measurement of the performance. In many applications of propeller fans, air is circulated without encountering resistance and no static pressure is developed. The static efficiency is zero and its calculation is meaningless. Because of such situations where the static efficiency fails to indicate the true performance, many engineers prefer to base the calculation of efficiency upon the total or dynamic . pressure. This efficiency is variously known as the total, dynamic7, or mechanical efficiency, and may be expressed as follows: Mechanical or Total efficiency1 cfm X total pressure in inches of water 6356 X Horsepower input (3) CHARACTERISTIC CURVES In the operation of a fap at a fixed speed the static and: total efficiencies vary with any change in the resistance which is imposed. With different designs the peak of efficiency occurs when the fans deliver different per- 'See Standard Test Code for Centrifugal and Axial Fans, Third Edition of 1938. 517 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 centages of their wide-open capacity. Variations in efficiency accompany variations in pressures and power consumption which are characteristic of the individual designs and which are influenced particularly by the shape and angularity of the blades. Such variations in pressure, power, and efficiency are shown by characteristic curves. Characteristic curves of fans are determined by tests performed in accordance with the Standard Test Code for Centrifugal and Axial Fans2 prepared jointly by the American Society of Heating and Venti lating Engineers and the National Association of Fan Manufacturers. The results of tests are plotted in different ways: the abscissae may be the CHAPTER 28. FANS Axial flow fan characteristics are indicated by Figs. 1 and 2. These fans, when properly designed, have a satisfactory efficiency at low resistance, comparing favorably in this respect with centrifugal fans. They are low in cost and economical in operation and occupy relatively little space. Although this type of fan can operate against considerable resistance, the noise often becomes objectionable, so that it does not always compare favorably with centrifugal fans for such service. With most of the designs which employ blades of uniform thickness the power increases rapidly with an increase in resistance. The curves (Fig. 1) show the rapid reduction in capacity and increase in power as the resistance increases. The low efficiency when overcoming Fig. 1. Operating Characteristics of an Axial Flow Fan ratio of delivery, assuming full open discharge,.as 100 per cent, and the ordinates may be static pressure, dynamic pressure, horsepower and efficiency. Pressures may be expressed in per cent of the maximum pres sure in the manner shown in the illustrations in this chapter, but in engineering calculations they are sometimes expressed in proportion to the pressures due to the peripheral velocity. It should be noted that characteristic curves of fan performance are plotted for a constant speed. Some variation in values of efficiency may occur at different speeds but such variation is usually slight within a wide range of speeds. Fans of similar design but of different size will also show some difference in efficiency. Figs. 1 to 4 show characteristic curves for different types of fans using blades of various shapes, but without reference to the design of housing employed. The efficiency curves are therefore not serviceable for making rigid comparisons of efficiencies obtainable with blades of the various shapes but are intended merely to show reason able values and more particularly to show the manner in which variations occur with changes in fan capacity. A.S.H.V.E. Transactions. Vol. 29. 1923. p. 407. Amended in A.S.H.V.E. Transactions. Vol. 37, 1931. p. 363. Third Edition of 1938. 518 heavy resistance is due to the low speed of the blades near the hub as compared to the relatively high peripheral or tip speed. The air driven by the blade area near the rim can pass back through the less effective blade area at the hub more easily than it can overcome the duct resistance. Fig. 2 shows the performance of the airplane propeller fan in which the blades are similar in shape to those of an airplane propeller but of varying number according to the pressure to be developed. This fan usually operates at a higher speed than does the former type of propeller fan, and with a different power characteristic, the power remaining fairly constant throughout the range of pressures, being somewhat less at the higher than at the lower pressures. The flatness of the horsepower curve indicates the advantage of this type of fan in preventing overloading of motors where fluctuations in pressure occur. Variations in the diameter, width, pitch, camber, and the thickness of the blades provide a considerable degree of flexibility in design, so that the peak of total efficiency may be made to occur at wide-open volume or at various percentages of that volume. Another advantage of this type of axial flow fan is its low resistance to air passage when standing still. There are some installations in which such a characteristic is desirable. 519 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 The straight blade (paddle-wheel) or partially backward curved blade type of fan is practically obsolete for ventilation. Its use is largely con fined to such applications as conveyors for material, or for gases con taining foreign material, fumes and vapors. The open construction and the few large flat blades of these wheels render them resistant to corrosion and tend to prevent material from collecting on the blades. This type of , fan has a good efficiency, but the power steadily increases as the static pressure falls off, which requires that the motor be selected with a moder ate reserve in power to take care of possible error in calculation of duct resistance. CHAPTER 28. FANS makes it adaptable for direct connected electric motor drives." The high speed may necessitate somewhat heavier construction and more operating attention or service. The dimensional bulk for a given duty often is 150 per cent of that of a forward curve multiblade type fan. Between the extremes of the forward and the full backward curve blade type centrifugal fans a number of modified designs exist, differing in the angularity or in the shape of the blades. Common among these designs are the straight radial blade type, the radial tip type, and the double curve blade type with a forward angle at the heel and a slight backward angle at the tip of the blade. Characteristic curves of these types show Fig. 3. Operating Characteristics of a Fan with Blades Curved Forward The forward curved multiblade fan is the type most commonly used in heating and ventilating work, as it has a low peripheral speed, a large capacity, and is quiet in operations The point of maximum efficiency for this fan occurs near the point of maximum static pressure. The static pressure drops consistently from the point of maximum efficiency to full open operation. The power curve rises continually from low to peak capacity, but if reasonable care is exercised in figuring resistance there is no danger of overloading the motor; The outstanding characteristics of the full backward curve multiblade type fan are the steep pressure curves* the non-overloading power curve, and the high speed. (See Fig. 4.) -This fan operates at a peripheral speed of approximately 250 per cent of the forward curve multiblade type for like results. The pressure curves begin to drop at very low capacity and continue to fall rapidly to fufl outlet' opfening. The steep pressure curves tend to produce constant capacity under changing pressures. Where wide fluctuations in'demand occur, this type of fan is desirable to prevent overloading of motors. The maximum power requirement occurs at about the maximum efficiency. Consequently a motor selected to carry the load at this.point will be of sufficient capacity to drive the fan over its full range of capacities at a given speed-. The. high speed of this type 520 varying degrees of resemblance to the curves of Figs. 3 and 4, according to the degree of similarity to one or the other of the.two designs of fan considered. SYSTEM CHARACTERISTICS A given fan performs as determined by the real characteristic of the system tp which it is attached. When-a different performance of a fan is desired, it is necessary to either change the speed of the fan (as A to B or C to D in Fig. 5), or to change the system (as by moving a damper from A to C in Fig. 5). If the speed of the fan is changed, the new point of opera tion is the intersection of the constant speed static pressure--cubic feet per minute curve for the new speed with the system characteristic. If the system is changed, the new point of operation is the intersection of the constant speed static pressure, cubic feet per minute curve with the hew system characteristic. Heating and ventilating systems follow the simple parabolic law quite closely but other types of systems follow some other more or less complex relation. The more complex systems can be separated into their com ponent parts whose individual characteristics are known and the sum mation of the characteristics of the several parts of a system will give the composite characteristic of the system. ' 521 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 SELECTION OF FANS The following information is required to select the proper type of fan: 1. Cubic feet of air per minute to be moved. 2. Static pressure required to move the air through the system. 3. Type of motive power available. 4. Whether fans are to operate singly or in parallel on any one duct. 5. What degree of noise is permissible. 6. Nature of the load, such as variable air quantities or pressures. Knowing the requirements of the system, the main points to be con sidered for fan selection are (1) efficiency, (2) speed, (3) noise, (4) size and weight, and (5) cost. In order to facilitate the choice of apparatus, the various fan manu facturers supply fan tables or curves which usually show the following factors for each size of fan operating against a wide range of static pressures: ., 1. Volume of air in cubic feet per minute (68 F, 50 per cent relative humidity, 0.07488 lb per cubic foot). 2. Outlet velocity. 3. Revolutions per minute. 4. Brake power. ' 5. Tip or peripheral speed. 6. Static pressure. 522 CHAPTER 28. FANS The most efficient operating point of the fan is usually shown by either bold-face or italicized figures in the capacity tables. Fans for Ventilating and Air Conditioning Systems Two important factors in selecting fans for ventilating systems are efficiency (which affects the cost of operation) and noise. First cost and space available are secondary. The fans should be selected to operate at maximum efficiency without noise. Because noise in a ventilating system Is irritating and a cause for complaint, fans must be selected of proper size in order to reduce it to a minimum. Noise may be caused byother factors than the fan, namely, high velocity in the duct work, unsatisfactory location of the fan room, improper construction of floors and walls, and poor installation. Where noise is chargeable directly to the fan, it is caused either by excessive peripheral speeds, or the fan is of insufficient size. It should be remembered, however, that the tip speed Table 1, Good Operating Velocities and Tip Speeds for Forward Curved Multiblade Ventilating Fans 1Static *assauna Inches or Water x % M % Vi % 1 IK m 2 2K 2K 3 * Outlet Vblocitt Feet per Minute 1000-1100 1000-1100 1000-1200 1100-1300 1200-1400 1300-1600. 1500-1800 1600-1900 1800-2100 1900-2200 2000-2400 2200-2600 2300-2600 2500-2800 Tip Speed Feet pbb Minute 1520-1700 1760-1900 1970-2150 2225-2450 2480-2700 2660-2910 2820-3120 3162-3450 3480-3810 3760--4205 4000--4500 4250-4740 4475-4970 4900-5365 required for a specified capacity and pressure varies with the type of blade, and that a tip speed which may be excessive for the forward curved type is not necessarily so for the backward or slightly backward type. A noisy fan usually is one which is operated at a point considerably beyond maximum efficiency. For a given static pressure there is a corresponding outlet velocity and peripheral speed wherein maximum efficiency is obtained. If a fan is selected to operate at this point, the cost of operation and the noise can be held within control. To aid in selecting fans as near as possible to the point of maximum efficiency, there are listed in Tables 1 and 2 for each static pressure cor responding outlet velocities and tip speeds which will give satisfactory results. The proper tip speed for a given static pressure varies with the design of wheel and with the number of blades or vanes in the wheel. ' Lower outlet velocities than those listed in Table 1 may be employed, but care must be exercised to avoid selecting a fan for operation below its useful range. The useful range of the fans of Table 2 extends over the full length of the performance curve. 523 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 In exhaust ventilating systems where the air column moves toward the fan, noise due to the higher tip speeds and outlet velocities will not be so readily transmitted back through the air column to the building as when the air column is moving toward the rooms. Therefore higher outlet velocities may be used, but this will be at the expense of increased horsepower. Amply large fans should always be used for both exhaust and supply systems, as there may be and usually is leakage despite the most careful workmanship, necessitating the delivery of more air at the fans than is exhausted from or supplied through the openings in the Various rooms. Long runs of distributing ducts, heaters, and air washers require definite increments of the total pressure which a supply fan in a venti lating system must overcome. These static pressures should be con sidered when selecting the fan characteristics, speed, and power. Table 2. Good Operating Velocities and Tip Speeds for Multiblade Ventilating Fans with Backward Tipped and Double Curved Blades Static Pbessdrb Inches of Water K. H K H K Ys l IK IK IK 2 2K 2K 3 Outlet Velocity Feet psb Minute 800-1100 800-1150 900-1300 1000-1500 1100-1650 1200-1750 1200-1900 1300-2100 1400-2300 1500-2500 1600-2700 1700-2800 1800-2950 2000-3200 Tip Speed Feet peb Minute 2600-3100 3000-3500 3400-4000 3800-4500 4200-5000 4500-5300 4800-5750 5300-6350 5750r-6950 6200-7550 6650-8050 7050-8550. 7450-9000 8200-9850 . Fans picked within the limits of Table 1 will operate close, to the point of maximum efficiency. No attempt has been made to select these limits for quiet operation,,since this is a relative term and varies with the type and location of the installation. The connection of a fan to a metallic duct system should be made by canvas or a similar flexible material so as to prevent, the transmission of fan vibration or noises. Where noise prevention is a factor the fan and its driver should have floating foundations. 'j Fans for Drying ` . Both axial flow and centrifugal types of fans are used for drying work. Propeller fans are well adapted to the removal of moisture-laden air when operating against low resistance and when handling air at low tempera tures. Motors on these fans usually are of the fully-enclosed moistureproof types so that saturated air or air containing foreign material will not injure the motors. Unit heaters employing axial flow fans are widely used in the drying 524 CHAPTER 28. FANS field. In drying, these fans may be used with unit heaters where not too much duct work is required and where air is to be delivered against pressure, since the noise developed from the high peripheral speed of these fans is not ordinarily objectionable in process work. Centrifugal fans of the multiblade type generally are selected to supply air for drying, as they are capable of delivering large volumes of air against all pressures likely to be encountered. Belt-driven fans usually are to be preferred to direct-connected fans since efficient motor speeds do not usually coincide with efficient fan speeds. . Replacement of a standard motor is quick and easy if it is belted. Wherever drying is done throughout the year and where air require ments change as the drying conditions change, the drying can be speeded up or reduced through control of the fan capacity. This may be done by changing the fan speed or by varying the outlet area with dampers. A throttled outlet reduces the volume and reduces the power. Due to the low speeds of forward curved multiblade or paddle-wheel type fans, these can be direct-connected to reciprocating steam engines, and the exhaust steam from the engines may be used in the heating apparatus. In selecting engine-driven fans for drying processes, where a large quantity of exhaust steam is used in the heaters, a smaller fan and greater power consumption may be used, because power economy is not essential under this condition. Where static pressure in a drier varies, and where several fans must operate in parallel, fans are to be preferred which have a continuously rising pressure characteristic, such as is given by backward-curved or double-curved blades. This type of fan is well adapted for direct-con nected motors of the higher speeds. (See Chapter 36 on Drying Systems). Fans for Dust Collecting and Conveying . The application of fans for handling refuse, dust, and fumes generated by machine equipment is covered in Chapter .35. Information is given regarding the methods for determining air quantities, the velocity required for carrying various materials and the method of determining maintained resistance or total static pressure at which the fan is to operate. The selection of a proper size fan is at times governed by the future require ments, of the plant. In many instances, additional future capacity is anticipated and should be provided for. Having determined the necessary volume of air and the maintained resistance or static pressure required, the proper size fan may be selected from the fan manufacturers' performance charts or capacity tables. The fan chosen should be the size that will provide the required ultimate quantities with the minimum power consumption. FAN VOLUME CONTROL Some method of volume control of fans usually is desirable. This may be done by varying the peripheral velocity or by interposing resistance, as by throttling-dampers. Both methods, since they reduce the volume of . air, reduce the power required. In many installations adjustments of volume are desirable during varying hours of the day. In others an 525 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 !l CHAPTER 28. FANS 'increased supply of air in summer over that needed for winter is demanded. Experience is required in deciding whether speed-control or dampercontrol shall be used for specific cases. Where noise is a factor, it may be exceedingly desirable to reduce the speed at times, while on the other hand, any fan which has its normal speed reduced as much as 50 per cent without change in resistance will move only 50 per cent of the air. FAN DESIGNATIONS Facing the driving side of the fan, blower, or blast wheel, if the proper direction of rotation is-clockwise, the fan, blower, or blast wheel will- be designated as clockwise. If the proper direction of rotation is counter-clockwise, the designation will be counter clockwise. (The driving side of a single inlet fan is considered to be the side opposite the inlet regardless of the actual location of the drive.)* This method of designation will apply to all centrifugal fans, single or double width, and single or double inlet. Do not use the word "hand," but specify "clockwise" or "counter-clockwise." The discharge of a fan will be determined by the direction of the line of air discharge and its relation to the fan shaft, as follows: Bottom horizontal: If the line of air discharge is horizontal and below the shaft. Top horizontal: If the line of air discharge is horizontal and above the shaft. Up blast: It the line of air discharge is vertically up. Doom blast: If the line of air discharge is vertically down. All intermediate discharges will be indicated as angular discharge as follows: ` Either top or bottom angular up discharge or top or bottom angular down discharge, the smallest angle made by the line of air discharge with the horizontal being specified. In order to prevent misunderstandings, which cause delays and losses, the arrangements of fan drives adopted by the National Association of Fan Manufacturers and indicated in Fig. 6 are suggested. If double width, double inlet fans are selected, care must be taken that both inlets have the same free area. If one inlet of a fan is obstructed more than the other, the fan will not operate properly, as one half of the wheel will deliver more air than the other half. The backward curved and double curved types with backward tip operate satisfactorily in double or in parallel operation. MOTIVE POWER It is no easy matter to predetermine the exact resistance to be encoun tered by a fan or, having determined this resistance, to insure that no changes in construction or operation shall ensue which may increase air resistance, thus requiring more fan speed and power to deliver the required volume, or which may reduce air resistance, thus causing delivery of more air and a consequent increase of power even at constant speed. It is recommended, therefore, for centrifugal type fans that the rated power to be supplied shall exceed the rated fan power by a liberal margin , when forward curved types are used. When backward, or double curved blade types are used, motors with ratings very close to that of the fan horsepower demand can be employed, provided the fan has a limiting horsepower characteristic. 526 'Recommendations adopted by the Notional Association of Fan Manufacturers. 527 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Justification for liberal power provision exists also in the possibility of varying demand due to changes in ventilation requirements, intensity of occupation, and weather conditions. The motive power of fans should be determined in accordance with the Standard Test Code for Disc and Propeller Fans, Centrifugal Fans and Blowers, as adopted by the American Society of Heating and Venti lating Engineers and the National Association of Fan Manufacturers. Fans may be driven by electric motors, steam engines (either horizontal or vertical), gasoline or oil engines, and turbines, but as previously stated the drive commonly used is the electric motor. REFERENCES Mine Ventilation, by J. J. Walsh (A.S.H.V.E. Transactions, Vol. 23, 19170p. 659). Fan Blower Design, by H. F. Hagen (A.S.H.V.E. Transactions,Vol. 23, 1922, p. 175). The Specific Characteristics of Fans, by M. C. Stuart and J. B. Lusk (A.S.H.V.E Journal Section, Heating, Piping and Air Conditioning, September, 1936, p. 507). Non-Dimensional Fan Characteristics, by H. Carlton Moore (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, September, 1937, p. 580). Section X, A.S.H.V.E. Code of Minimum Requirements for the Heating and Venti lation of Buildings (Edition of 1929). Coal Miners Pocket Book. Constructive Mechanism and the Centrifugal Fan, by George D. Beals. Fans, by Theodore Baumeister, Jr. Fan Engineering, Buffalo Forge Company. Heating, Ventilating and Air Conditioning, by .Harding and Willard; Revised Edition, 1932. . . Mechanical Engineers' Handbook, by Kent. Mechanical Engineers' Handbook, by Lionel S. Marks. The Centrifugal Fan, by Frank L. Busey. The Fan, by Charles H. Innes. The Theory and Performance of Axial-Flow Fans, by L^S Marks and J. R. Weske. Theories and Practices of Centrifugal Ventilating Machines, by D. Murgue, trans lated by A. L. Stevenson. \ 528 Chapter 29 AIR DISTRIBUTION Definitions, Grille Locations, Standards for Satisfactory Con ditions, Factors Affecting Distribution for Cooling and Heat ing, Air Outlet Noises, Selection of Supply Outlets, Balancing System CORRECT air distribution contributes as much or more to the success of a forced air heating, ventilating, cooling or air conditioning system as does any other single factor. Supplying the proper amount of air is one problem; properly distributing it from the point where it.leaves the fan is another. The distribution problem may be further divided into: (a) distribution to the various spaces served by the system, (6) distribution in these spaces. This discussion is primarily limited to division (6), reference being made to the duct system only insofar as it affects the performance of the air distribution outlets. Definitions 1. Supply Opening: Any opening through which air is delivered into a space which is being heated, or cooled, or humidified, or dehumidified, or ventilated. 2. Exhaust Opening: Any opening through which air is removed from a space which is being heated, or cooled, or humidified, or dehumidified, or ventilated. 3. Outside Air Opening: Any opening used as an entry for air from outdoors. 4. Grille: A covering for any opening and through which air passes. 5. Daniper: A device used to vary the volume of air passing through a confined cross-section by varying the cross-sectional area. 6. Multiple Louver Damper: A damper having a number of adjustable blades. 7. Single Louver Damper: A damper having one adjustable blade. 8. Face: A grille with provision for attaching a damper. 9. Register: A face with a damper attached. 10. Flange: The portion (either integral or separate) of a grille, face, or register extending into the duct opening for the purpose of mounting. 11. Frame: The portion (either integral or separate) of a grille, face, or register extending around the duct opening for the purpose of mounting. 12. Margin: The margin of a grille, face, or register is one-half of the difference between the duct dimension and over-all dimension measured either horizontally or vertically. 13. Fret: The member separating the openings of a grille, face, or register. 14. Free Area: The total minimum area of the openings in the grille, face, or register through which air can pass. 15. Core Area: The total plane area of the portion of a grille, face, or register bounded by a line tangent to the outer edges of the outer openings through which air can pass. . 16. Mean Area: The total of the core and free areas divided by two. 17. Duct Area: The area of a cross-section of the duct based on the inside dimensions at the point where the grille, face or register is mounted. 529 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 18. Percentage Free Area: The ratio of the free area to the core area expressed in percentage. 19. Dimensional Ratio: The ratio of length of the core of a grille, face or register to the width. 20. Throw: The distance air will carry measured along the axis of an air stream from the supply opening to the position in the stream at which air motion reduces to 50 fpm. 21. Envelope: The outer boundary of an air stream. GRILLE LOCATIONS The location of supply and exhaust outlets is extremely important if a satisfactory installation is to be secured. Very frequently, however, the room or building is planned and constructed with practically no con sideration of this problem. The engineer of today is more likely than not to have as his problem a building that was constructed long before any consideration whatever was given to air conditioning it. Consequently, the room shapes, the location of columns and beams, and other details of architecture frequently make it difficult to properly locate the supply openings. In general, for a cooling installation, the grilles should be located high enough from the. floor to prevent the discharge of air directly upon the occupants of the room, and far enough down from the ceiling to CHAPTER 29. AIR DISTRIBUTION The location of supply openings should, if possible, be such as to take advantage of the maximum velocity permissible from a noise standpoint. For instance, the spaces illustrated in Figs. 1 and 2 may be satisfactorily ' served by either arrangement. However, by taking advantage of the long throw, to which the arrangement in Fig. 1 lends itself, fewer supply openings are required and additional savings are effected in the sheet metal work. In solving the problem of properly conditioning a room of irregular shape, where multiple wall supply grilles are objectionable, a ceiling sup ply opening of the type illustrated in Figs. 3 and 4 may very often be the best solution. In choosing the most desirable location for the return air grille, con sideration should be given to its effect on circulation of the air through the room. It is generally true that the return air grille should be placed on the same wall as the supply and near the floor level. This results in a U-shaped air path (Fig. 5) which covers the room thoroughly. The arrangement shown in Fig. 6 should be avoided, because it tends to create Fig. 1. Plan View Long Throw Supply Opening Fig. 2. Plan View Short Throw Supply Openings minimize the possibility of streaking, and to permit induction of air from all sides of the stream. If the stream actually strikes the ceiling, but at a small angle, the throw will be increased somewhat if the ceiling is smooth. If the angle at which the stream hits the ceiling-is .20 deg or more, or . if the flow along the ceiling is obstructed by panel mouldings or beams, air velocity may be rapidly lost and a decreased throw result. The air stream also should be so directed that it will not strike nearby columns or beams in such a way as to cause misdirection of the air stream or drafts. Where the room is of irregular shape, as an ell, or where it has an alcove in one side, consideration should be given to obtaining satisfactory circulation in these corners. Frequently this cannot be done except by the use of multiple supply openings. In using multiple supply openings, care must be taken that the several air streams do not interfere with each other, until their velocities have been reduced to values which will not cause high turbulence and a drafty condition. Beams and offsets in the ceiling will cause little difficulty when substantially parallel to the direction of flow, unless they are of considerable depth, but when po sitioned across the air stream, may cause drafts and failure to secure satisfactory circulation in that portion of the room farthest from the supply opening. In the case of a heating installation, down-drafts pro duced by such obstructions may not be serious, because the air will rapidly lose its downward motion, but the possibility of failure to obtain satisfactory circulation still exists. 530 Fig. 3. Elevation View Ceiling Supply Outlet with Return Wall Outlet Fig. 4. Elevation View Ceiling Supply and Return Outlet a stagnant section below the supply grille. What would otherwise be an unsatisfactory dead spot in a room may in some instances be taken care of by location of the return air grille near that area (Fig. 7). STANDARDS FOR SATISFACTORY CONDITIONS The most satisfactory air condition cannot be definitely stated for any particular individual without conducting a series of tests with that individual as subject; some persons are less sensitive than others to variations in temperature, humidity, air velocity and noise. The best that can be done is to attempt to set limiting conditions leaning toward the values of these variables which produce a condition of comfort for the greatest number of individuals. On a cooling installation, the allowable deviation from average room temperature, that is, the temperature of puffs of air which may strike a person momentarily, is a function of the room temperature as well as the velocity of the air. For instance, in a room controlled at 72 F, a puff of air at 70 F might be uncomfortable to an individual, even at relatively low velocities, whereas if the average room temperature were 80 F, air at 78 F, even at moderate velocities, might be/very satisfactory. However, air at 78 F in an average room 531 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 temperature of 83 F would be cold. In general, other conditions being equal, for the range of temperatures normally encountered in living quarters on cooling installations, the permissible deviation from average room temperature varies from approximately 1 F at the low end of the range to about 3 F at the high end of the range. In this matter, it is important to consider the particular problem in the light of the type of occupancy. For instance, greater deviations from room temperature arid higher velocities may be permitted in a garage or a hotel hallway than would be permissible in an office or living room. The velocity which may be considered the permissible maximum differs with the temperature deviation for a given installation, but an absolute maximum under any conditions might be considered that which would produce a mechanical CHAPTER 29. AIR DISTRIBUTION perature is counteracted to a certain extent so that an individual may be subjected to higher velocities of warm air without the feeling of dis comfort occasioned by the same velocities of cool air. In every case, it should be the purpose of the designirig engineer to keep the conditions within the zone of occupancy as nearly uniform as possible, securing minimum temperature deviations and low velocities. The air velocity at all points in the room should be at least 25 fpm for good results. It is impractical to measure momentary temperature differences with any degree of accuracy in the field, but in checking a given installation it will generally be found satisfactory to measure velocity only, since on cooling installations high velocities normally occur with low temperatures, and on heating installations high velocities occur with high temperatures. That is, in the former case, the chilled supply air loses its velocity and undergoes an increase in temperature as it settles into the occupancy zone, whereas in the latter case the heated supply air loses its velocity arid undergoes a decrease in temperature during this process. Therefore, if the Fig. 5. Elevation View Correctly Located Return Outlet Fig. 6. Elevation View of Improperly Located Return Outlet disturbance, such as the movement of a person's hair or disturbance of papers on a desk. Humidity is an important consideration in the deter mination of one's feeling of comfort; however, if the room generally is assumed to be at a satisfactory value of relative humidity, the designer is justified in neglecting this factor when considering permissible fluctuations in temperature and velocity in the occupancy zone. This is true beeause the maximum allowable temperature fluctuation results in an unnoticeable humidity change. The standards that might be set up for maximum allowable room temperature deviation and air velocity would not be the same for both heating and cooling installations. In the former case, any appreciable temperature deviation is likely to be above rather than below the average room temperature, whereas the reverse is most likely to be true on a cooling installation. Further, because air movement has a cooling effect in itself, the feeling of warmth due to temperatures above room tern- 632 Fig. 7. Plan View Correctly Located Return Outlet Eliminating Stagnant Space average velocities within the occupancy zone are not excessive, one is fairly safe in assuming that the temperature difference is also within permissible limits. The subject of sound control is covered in Chapter 31 and it is recom mended for detailed review before consideration of the problem of air supply opening noise. An understanding of the relation between sound intensity and loudness level in decibels, as well as the effect of the presence of sound absorbent materials in the room, is particularly necessary. A more detailed discussion of the nature of this problem appears later; whereas the following comments refer to what constitutes a satisfactory noise condition. . Obviously, the-nature of the conditioned space is important when con sidering the allowable supply opening noise. In factories, press rooms, and similar spaces where the noise level is 65 db or higher, no complaints of grille noise are likely to be made. On the other hand, some homes, offices, hospitals, and, most of all, radio broadcasting and movie sound studios, present a real problem which must be intelligently attacked if a satisfactory installation is to be made. In this chapter the noise of the air supply openings (and returns) only is considered, it being assumed that the noise or sound level of the room without the supply opening noise 533 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 includes that which may be contributed by fans, motors, duct work, and other items of conditioning equipment. The control of noise from these sources is another problem (see Chapter 31). Where sound control is important, the actual room sound level without conditioning equipment should be known. If feasible, the contribution of the conditioning equipment, less supply openings, should be estimated to secure the working sound level. If this correction is not made, the use of the first value errs in the direction of safety. It is evident that the point within the room which should concern the designer in this problem is that at which the supply opening noise is greatest. A tentative standard listening point relative to the supply opening is suggested later in this discussion, and it is assumed that the supply opening noise data are taken with reference to this point. If it is desired that the supply opening noise result in an inaudible addition to the existing noise level, it is safe to assume the total supply opening noise to be 5 db below room level. This results in an increase in total noise of slightly over l .db, which is unnoticeable. If an increase of 3 db is per missible, the supply opening noise level may be equal to the room noise level alone. All supply openings in the room must be considered, as will appear later, and the returns may be ignored only if they are so sized that the velocity of air through them is much less than through the supply opening. DISTRIBUTION FACTORS IN ROOM COOLINC In attempting to design a satisfactory air distributing system, it is first necessary to properly locate the grilles in accordance with the recom mendations already stated. Assuming that the best locations have been selected, it then becomes necessary to choose the proper grille for that location. The considerations involved are the amount of air to be handled, the velocity permissible from the standpoint of noise, and the distance the air should carry. The distance it will carry, assuming no obstructions, is affected by a number of factors which-are listed below: 1. The temperature difference between incoming and room air. 2. Height of grille above floor. 3. Face velocity. . 4. Core area. 5. Design of grille. The manner in which the above factors affect throw may be generally stated. All other things being constant any one of these will produce a longer throw; a higher temperature of incoming air; a greater height above the floor; a higher velocity; a greater area. The design character istics of the grille will, of course, vary the throw. Dimensional ratios up to four have no appreciable effect, but greater ratios will decrease throw. The variation in throw with type of supply opening will, of course, depend upon the design characteristics of the supply opening. In consideration of what constitutes the possible throw of a supply opening under a given set of conditions, it is important to remember that the throw may be unsatisfactory for any one of several reasons: 534 CHAPTER 29. AIR DISTRIBUTION 1. It may be so long that it will strike the far side of the room and come down the wall with velocities higher than are permissible, 2. It may be so short that it will fail to carry the full length of the room, and shortcircuit to the return air supply opening, or 3. It may spill into the center of the room. In the first case, the system fails for lack of uniform distribution and the presence of cold areas. In the second case, the standards as to velocity and temperature difference in the zone of occupancy may be satisfactorily met, but air distribution and circulation throughout the entire room is not accomplished, with the result that the end of the room away from the outlet would not be satisfactorily conditioned. In the third case, the shortcomings of both case one and case two are present. It is evident, therefore, that for a given supply opening discharging air at a given velocity, there is a maximum and a minimum length of room which can be satisfactorily handled. In the latter, the velocity of the air down the far wall is just within the maximum permissible, while in the former, satisfactory circulation is barely accomplished. In general, the higher the supply opening is above the floor, the greater may be the difference between room air and incoming air temperatures. Assuming that proper supply openings for a given installation have been selected, unsatisfactory performance may still result due to the con struction of the duct work immediately back of the supply openings. Performance data on the grilles and registers of various manufacturers are based upon results obtained with the air approaching the grille perpen dicularly and at uniform velocity over the entire duct cross-section. Where this condition does not exist in practice, performance predictions based on published data cannot be expected to be realized. Every precaution should be taken to secure as nearly ideal conditions in the approaching air stream as are possible. In addition to disturbances due to the construction of the duct work itself are those which may be created by dampers immediately behind the grille. Where either multiple louver or single blade dampers are used, considerable deflection of the air stream may result, if it is throttled appreciably by these means. This is particularly true when the fins of the register core are perpendicular to the damper blades. If the core has sufficient depth and the fins are parallel to the blades, there is a marked tendency to straighten the air stream, although some deflection may still result. Any attempt to secure a low face velocity and high duct velocity by the construction of any expanding chamber immediately behind the grille is likely to be unsuccessful. In order to expand from a small duct to a larger one, and have the air stream fill the duct at the end of the diverg ing section without turbulence, angle A in Fig. 8 should be about 3 deg for four-sided expansion and about 5 deg for two-sided expansion. From this it is apparent that an attempt to secure equivalent results with a short connection would be futile. What actually happens when this is attempted is illustrated by the arrows in Fig. 8. When localized high velocities through the supply opening exist from this cause or any other, the noise produced will, naturally exceed that which the supply opening area and average face velocity would lead one to expect. This fact should 535 ' HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 be remembered in considering the use of register dampers, particularly in those cases where there must be considerable throttling with the damper to balance a poorly designed system. Where reduction, of noise is im portant, it is recommended that balancing dampers be placed in the duct ahead of the acoustic duct lining. . Similar unequal face velocities, aggravated by a deflection of the air ' stream, are obtained with the arrangement shown in Fig. 9. The latter may be corrected by inserting a turning member in the elbow back of the outlet face as shown in Fig. 10. The importance of straightening the air stream and affecting uniform distribution over the entire face of the supply opening cannot be over-emphasized. DISTRIBUTION FACTORS IN ROOM HEATING The problem in the case of a heating installation is substantially the same as in cooling, with a few exceptions. Because the temperature of the incoming air is above that of the room, there is no tendency for it to drop and consequently the throw is not particularly affected by tem- Fig. 8. Effects of Expanding Duct Fig. 9. Unequal Face Velocities . Fig. 10. Effect of Turning Member perature difference in a low ceiling room. In general, the air should be deflected downward where the grille is above the occupancy zone, and this is particularly desirable where the ceiling is high. For the same reason, that is, to keep the heat in the occupancy zone and to avoid excessive temperature at the ceiling, it is desirable to have the grille comparatively low on the wall, and just slightly above the occupancy zone. If the grille is lower than this, it may create an unsatisfactory condition of very warm air at quite high velocities where it can possibly strike the occupants of the room. Where the velocities are very low, the grilles may even be satisfactorily located below the 6-ft level, although the immediate vicinity of the supply openings will probably be useless for occupancy because of high temperature. Essentially, the problem is to keep the incoming air up for cooling, and down for heating, until it is thoroughly mixed with the room air. Grilles and registers which are adjustable for deflection upward and downward, either by moving the fins or inverting the grille, are in general use. AIR SUPPLY OPENING NOISES When air is introduced into a room through a grille or register at a constant velocity, sound energy is being introduced into the enclosure at 536 CHAPTER 29. AIR DISTRIBUTION a constant rate. Due to partial reflection at the boundaries of the en closure, the intensity of sound at any point in the space builds up to some maximum value. In a large room at a point remote from the source of sound (the supply opening) the intensity can be shown to be substantially proportional to the rate at which sound energy is generated and inversely proportional to the number of sound absorption units (sabins) in the room. It would thus appear that doubling the sound absorption of the room would halve the intensity and result in a noise level decrease of 3 db. However, it is not satisfactory to consider the grille noise on this basis (wherein the sound power received directly from the source is small compared with that received by reflection) since in practice the occupants of the room may be quite close to the grille. The nearer the listener is to the sound source, the greater the proportion of the sound intensity which is due to direct transmission. In the absence of generally accepted standards at this time it is sug. gested that the loudness level 5 ft from the lower edge of the supply opening, measured downward at 45 deg in a plane perpendicular to the supply opening at its center, represents about the maximum within the zone of occupancy. The cases where persons are nearer to the supply opening than this are rare and are ignored in the consideration of this problem. Although the effect of sound absorbent material on the in tensity at the 5-ft station is not nearly so great as at more remote points in the room, it should not be ignored without consideration of the error involved. An average living room may contain 100 sabins (absorption units). If this be decreased to 50 sabins, the diffuse or reflected sound level would be increased 3 db. However, at the 5-ft station the increase would be less than 2 db. If the absorption of the room be increased to 200 sabins, one might expect a reduction in diffuse noise of 3 db; but at the 5-ft station the reduction would be less than 1)4 db. Furthermore, even though the absorption be increased without limit (as in free space) the reduction would still be less than 2 db because of proximity to the source. In comparing sound ratings of various grilles, the following must be known if the information is to be intelligently applied: 1. The threshold intensity on which the decibel ratings are based. 2. The distance from the grille at which data were taken. 3. If .stated as loudness level versus velocity for a given grille, the core area (not nominal area) must be known. 4. The sound absorbing characteristics of the test room. 5. Whether or not corrected for test room loudness level; if not, the room level (without grille noise) must be known. 6. Methods used for recording data. Data mentioned in this chapter are assumed to have been referred to' the following: 1. Threshold intensity = 10-u watts per square centimeter1. 2. Microphone location 5 ft from lower edge of supply opening on a line downward at 45 deg and in a plane bisecting the supply opening perpendicularly. 3. Where data are given as loudness level versus velocity, the rating is per square foot of core area. 4. The room is assumed to have 100 sabins absorption. American/Tentative Standards for Noise Measurement, American Standards Association. 537 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 5. Plotted data are loudness levels of supply openings only, correction having been made for test room level. 6. Data taken with a direct reading sound-level meter with frequency weighing network intended to approximate the response of the human ear. If the published ratings are in terms of decibels per square foot, cor rection must be made for area to secure to total sound level of supply openings of more or less than one square foot area. This can be done by use of the following formula: Decibel Addition = 10 logu>4 (1) where A -- core area, square feet. CHAPTER 29. AIR DISTRIBUTION 35 db, a velocity (Fig. 11) of about 725 fpm may be used. From this velocity and the rate of flow, the core area can be computed. This determination was on the basis of a room absorption of 100 sabins. If the absorption is greater, the 725 fpm velocity is safe, since the loudness level will go down. However, correction can be made if desired by the use of the chart of Fig. 12. Thus, if the absorption is 200 sabins, a cor In practice the allowable total sound and the required air flow are usually known, and it is desired to determine the maximum allowable velocity. Since total loudness and air flow are both functions of velocity and area, the solution of the problem by use of the previous analysis implies a trial and error method. It has been found possible to present these data with sufficient practical accuracy as a family of uniform curves as illustrated in Fig. 11. With this chart it is .possible to find directly the velocity in feet per minute which will give a predetermined total loudness at a predetermined rate of flow expressed in cubic feet per minute. The values used are arbitrarily chosen for the purpose of discussion and do not necessarily represent data referring to any particular make of grille, register or air supply opening. It is assumed that Fig. 11 is based on a room having 100 sabins of sound absorption. In such a room the sound level due to other sources may be 40 db. As previously stated a supply opening having a noise level of 35 db would be substantially inaudible in such a room. If 2400 cfm are required with a total noise due to supply opening of 638 rection of +1.3 db may be made and the permissible velocity becomes that corresponding to a total loudness level of 36.3 decibels or approxi mately 800 fpm. If the room is highly reflecting and has an absorption of less than 100; correction is much more important. For instance, for 35 sabins a correction of --3 db must be made and the maximum velocity corresponding to 32 db total loudness chosen; that is, approximately 600 fpm; 539 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 .Where more than one supply opening must be considered, the problem is more complicated. If a similar supply opening is added in a far corner of a highly absorbent room, the change in noise level at the 5-ft station at the first supply opening is small; however,.if the room is small, or highly reverberant or both, the intensity at the 5-ft station may be almost doubled and the noise level increased nearly 3 db thereby. The simplest method of handling this problem, and one which errs in the direction of safety, is to treat the room as though all the air were being supplied by one supply opening. Thus, if two outlets, each supplying 1000 cfm are used, the value 2000 cfm should be used with Fig. 11. Although this method may place an unwarranted limit on velocity when used in a large room, it is seldom that such a room has a noise level low enough to make this penalty serious or to justify a more complicated though more exact procedure. ; In general, return grilles are selected for velocities about half the supply velocity, and when this is done, they may be neglected in sound computa tions. However, if supply and return grilles are the same size, resulting in the same face velocity, they must be treated as two supply openings. That is, if 1000 cfm is supplied and exhausted through grilles of the same area, 2000 cfm must be used in the solution with Fig. 11. SELECTION OF SUPPLY OPENINGS After the heating and cooling load calculations have been made (Chapters 7 and 8), and a suitable supply air temperature selected, the volume of air required for each space can be determined. The next step is to determine the velocity at which the air may be introduced into the space quietly and without creating objectionable drafts. Present day grille design coupled with the introduction of effective acoustical treatment for minimizing fan and duct noises have made grille face velocities in excess of 1500 fpm feasible, and 600 to 1200 fpm is now used in practice. This range of velocities is. approximately three times higher than common practice values of a few years ago. Since high velocities make for smaller ducts and supply openings, and therefore savings in space as well as greater flexibility in locating the duct work to the best advantage, selection of design velocities is a very important step. , ' The selection of proper velocity requires that the designer have reliable data applicable to the particular make of supply opening proposed for usage. Even under these circumstances, the problem is one of cut and try because permissible velocity may be limited by either noise or throw. A method for selecting supply openings is outlined below in the form of a sample cooling problem, using numerical values which have no reference to any. particular make of supply opening. X. The load calculations have been made; a suitable temperature differential has been selected (it is to be understood that the data referred to from this point on are based oh this temperature differential), and the volume of air required determined. Assume that Fig. 13 represents a small general office having a noise level of 40 db and that 2400 cfm must be supplied for proper conditioning. 2. Select a tentative location for the supply opening or openings, having in mind 540 CHAPTER 29. AIR DISTRIBUTION the type of grille.most likely to effect proper distribution. In this particular case, two supply openings haying a wide spread appears to be a logical choice. 3. Data from which to determine velocity which corresponds to 2400 cfm and a noise rating at least 5 db below the noise level of the office may be presented in a number of forms, one of which is shown in Fig. 11. (Fig. 11 represents assumed values only. In practice similar data should be obtained from the manufacturer whose supply openings are being'considered. Several similar charts or tables may be necessary to cover any one manufacturer's complete line.) From Fig. 11 it will be noted that for 2400 cfm the type of grille selected may be used at velocities up to 725 fpm without exceeding 35 db; that is, 5 db below the noise level of office. 4. Having determined the velocity, the core area becomes fixed at 3.31 sq ft or 397 sq in. per supply opening. In this problem, the two grilles in question are so close together that consideration of their combined area in determining the permissible velocity from the standpoint of noise introduces little error. 5. The type grille selected has thus far been found satisfactory from a noise stand point, provided the face velocity does not exceed 725 fpm. ' The next consideration is throw, which may be assumed to be 16 ft, and by reference to a manufacturer's catalogue the proper correlative test data may be checked with the throw assumed. It is of course evident that one or more types of grilles may satisfy the requirements, and that in any one type there will be a choice of supply opening proportions. It will also be evident that the tentative selection of a supply opening having a wide spread may be unsatis factory from the standpoint of throw, in which event a second choice should be made and the procedure repeated. In the case of a heating problem, the method of solution is the same, but the manufacturer's data must, of course, be based on tests with air above room temperature. TYPES OF SUPPLY OPENINGS Grille, register or supply opening design for attaining uniform distri bution and minimum air resistance consists of various fixed and adjustable arrangements. Some types are designed with directing air blades, fins, bars, louvers, or thin metal strips shaped into a series of grooves or tubes, all of which may be set into a suitable round, square or rectangular frame. In order to attain desired long or short air throws, the emergence of air from the supply opening may be directed to straight, deflecting, con verging or jet air streams depending upon the supply opening design. Designs which direct the air stream to produce an ejector effect within the enclosed space tend to mix the room air with the conditioned air to provide uniform distribution. 541 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Centrally located ceiling or wall type supply openings arranged for completely diffusing the air consist of several round, hollow, cone-shaped flaring members placed in the proper relationship to each other. The velocity of emergence of the air from the unit can be made practically uniform over the entire surface of the supply opening, and the velocity- in any direction may be varied to any desired value by adjusting the position of the cones. One or more of the smaller flaring members act as ejectors and injectors which draw a small proportion of the room air into the air spreader where it mixes with the conditioned air before it is dis charged. An idea for producing even distribution of air consists of a perforated ceiling made of a suitable architectural surface and installed a small distance below the normal ceiling level'of the room. In the space provided by this suspended ceiling a plenum chamber is formed into which the conditioned air is introduced. From the plenum space the air is permitted to diffuse through the large number of small ceiling openings into the room. . BALANCING SYSTEM In designing an air conditioning system, it should be the aim of the engineer to so proportion the duct system that proper distribution of air to every supply opening will be obtained. Since this is almost impossible to accomplish in practice, it becomes necessary to have means of balancing the system to secure the desired amount of air in each space. There are a number of ways in which this may be accomplished, some of which are: 1. Dampers on the supply and return grilles. 2. Dampers in the supply and return ducts. 3. Reducing the effective area of some supply openings by blank-offs. 4. Combinations of dampers in both supply and return air. . Dampers on the supply grilles themselves are objectionable because of their effect on the air stream. Dampers on the return grilles are frequently helpful in building up a static pressure in the room to prevent infiltration of outside air, and at the same time reduce the volume of incoming air. However, it is frequently impossible to sufficiently reduce the incoming air by this method alone. A damper in the supply duct some distance back of the supply opening forms a very satisfactory means of regulating the flow without disturbing distribution across the supply opening face. A damper in the return air duct has the advantage over one immediately behind the grille in that it does not tend to create high localized velocities through the grille as the latter might do if nearly closed. Blank-offs consisting of pieces of sheet metal covering a portion of the supply opening face can frequently be used satisfactorily, although determination of just what is required is a matter of experiment, and the balancing of the system is not nearly so conveniently accomplished as with dampers. Dampers in both supply and return air form the most flexible means of controlling the supply to the room and the static pressure within the room. When feasible, these dampers, particularly those in the supply ducts, should be a substantial distance from the supply opening, and ahead of the acoustic duct lining if used. Due consideration should also be given to the use of the several volume control and uniform distribution devices now available. See Catalog Data Section. 542 Chapter 30 AIR DUCT DESIGN Pressure Lasses, Friction Losses, Friction Loss Chart, Propor tioning the Losses, Sizes of Ducts, General Rules, Procedure for Duct Design, Air Velocities, Proportioning the Size for Friction, Main Trunk Ducts, Velocity Method, Equal Friction Method, Duct Construction Details THE flow of air due to large pressure differences is most accurately stated by thermodynamic formulae for air discharge under condi tions of adiabatic flow, but such formulae are complicated, and the error occasioned by the assumption that the gas density remains constant throughout the flow may be considered negligible when only such pressure differences are involved as occur in ordinary heating and ventilating practice. In the development of the formulae, diagrams, and tables for the flow of air, use is made of the following basic equation for the flow of fluids: If Hy be the velocity head in feet of a fluid, and the velocity, V, be expressed in feet per minute, the fundamental equation is . V = 60 ^2g Hy The factor g is the acceleration due to gravity, or 32.16 ft per second per second. It is usual to express the head in inches of water for ventilating work and, since the heads are inversely proportional to the densities of the fluids, hy d or 12 therefore, . Hy = 5.2 ' a . V = 1096.5 ^-^-r (1) where V = velocity in feet per minute. hy = velocity head or pressure in inches of water. d = weight of air in pounds per cubic foot. : For standard air (70 F and 29.921 in. barometer) tf = 0.07492 lb per cubic foot. Sub stituting this value in Equation 1: . F = !096.5 y^ = 4005 (2) 543 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Fig. 1. Curve Showing Loss of Pressure in Round Elbows The drop in pressure in air distributing systems is due to the dynamic losses and the friction losses. The friction losses for turbulent flow (which occur in all practical air flow problems) are due to the friction of air against the sides of the duct and to internal friction between air molecules. The dynamic losses are those due to the change in the direction or in the velocity of air flow. Dynamic losses occur principally at the entrance to the piping, in the elbows, and wherever a change in velocity occurs. The entrance loss is the difference between the actual pressure required to produce flow and the pressure corresponding to the flow produced; it may vary from 0.1 to 0.5 times the velocity head. The pressure loss in elbows must also be allowed for in the design. It is customary to express dynamic losses in Cturez-iwe Radius in Pczccnt or Pipe Width Fig. 2. Curve Showing Loss of Pressure in Square Elbows 544 CHAPTER 30. AIR DUCT DESIGN terms of the percentage of the velocity head; in other words, the per centage of that pressure corresponding to the average velocity in the duct which is expressed in terms of inches of water gage. Figs. 1 and 2 show the effect of changing the radius of 90 deg elbows of round' and square section1. These charts are based on tests of pipe elbows of ordinary good sheet metal construction. For .example, a fiye-piece round pipe elbow having a centerline radius of one diameter has a loss of about 25 per cent of the velocity head. At a velocity of 2000 fpm the corresponding head is 0.25 in. water gage, and at this velocity the elbow just referred to would cause a pressure drop of 0.063 in. water gage. The pressure loss through an elbow, may be assumed to be directly proportional to the angle through which the turn is made. This is approximately true for 90 deg elbows or less but varies considerably for higher degrees of turn. Experience has shown that good results may be obtained when the radius to the center of the elbow is 1% times the pipe diameter. The pressure drop will then be approximately 17 per cent of the velocity head for round ducts, and 9 per cent, for square ducts. Very little advantage is gained in making elbows with a centerline radius of more than two diameters2. Friction Losses Theoretically friction losses vary directly as the length of the duct, directly as the square of. the velocity, and inversely as the diameter. Since length is a fixed quantity for any system, the factors subject to modification are the area and the velocity, which determine the relation between the first cost of the duct system and the cost of the power for overcoming friction. ' ' The friction between the moving air and pipe surface and internal friction between air molecules cause a loss of head which is numerically equal to the pressure required to maintain a given velocity, and is ex pressed in the following modification of Fanning's formula: . : , For round pipe and standard air (70 F and 29.921 in. barometer) . For rectangular ducts " '/ where .. ' ht, ~ loss of head, inches of water. V \2 (4QQg 1 = velocity head, inches of water. V = velocity of air, feet per minute. L = length of pipe D = diameter of pipe all in feet, n. b = sides of rectangular duct / = coefficient of friction, or friction factor. . . C =y- = length of pipe in diameters for one head loss. (3) (4) 'Loss of Pressure Due to Elbows in the Transmission of Air Through Pipes or Ducts, by F. L. fiusev (A.S.H.V.E. Transactions, Voi. 19, 1913, p. 366). 'y 'Pressure Losses in Rectangular Elbows, by R. D. Madison and J. R. Parker (Healing, Piping and Air Conditioning, July, p. 365, August, p. 427, September, p. 483, 1936). 545 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 546 CHAPTER 30. AIR DUCT DES1CN For all practical purposes C varies only with the nature of the pipe surface: C = 60 for perfectly smooth pipe; = 55 for pipe as used in planning mill exhaust systems; = 50 for heating and ventilating ducts; = 45 for smooth and 40 for rough conduits of tile, brick or concrete. However, Fritzsche states (and numerous tests check very closely) that f varies inversely as the 2/7 power of the pipe diameter, and inversely as the 1/7 power of the velocity, or inversely as the 1/7 power of capacity, which is the same thing. Thus Formula 3 may be revised as follows, based upon a loss of one velocity head (at 2000 fpm) in a length equal to 50 diameters of 24 in. galvanized swedged pipe: hL = c511 ~ f7r~ (4^5 )W7 (5) The preceding formulae are based on standard air, and for other con ditions the friction varies directly as the air density or inversely (approxi mately) as the absolute temperature. The increase of friction due to increase of air viscosity with increased temperature is small arid is generally neglected. Friction Loss Chart Fig. 3 is a convenient chart for determining the friction loss for various air quantities in ducts of different sizes. The general form of this chart is familiar, but it should be noted that it is corrected for changes in the coefficient of friction based on the rule that the coefficient of friction varies inversely as the 2/7 power of the diameter, and inversely as the 1/7 power of the velocity. Fig. 3 is based on a loss of one velocity head (at a velocity of 2000 fpm) in a length equal to 50 diameters of 24 in. round galvanized iron duct of the usual construction. Although this chart is laid out for a value of C equivalent to 50, it may be used for other values of C by varying the friction inversely as this constant. For ex ample, if a rougher pipe is used with 40 as the value of C, the friction loss as read from the chart should be multiplied by --50. Example 1. Assume that it is desired to pass 10,000 cfm of air through 75 ft of 24 ini diameter pipe. Find 10,000 cfm on the right scale of Fig. 3 and move horizontally left to the diagonal line marked 24 in. The other intersecting diagonal shows that the velocity in the pipe is 3200 fpm. Directly below the intersection it is found that the friction per 100 ft is 0.59 in.; then for 75 ft the friction will be 0.75 X 0.59 = 0.44 in. In a like marir ner any two variables may be determined by the intersection of the lines representing the other two variables. . Proportioning the Losses Other losses of pressure occur at the entrance to the duct, through the heating units, at the air washer and at air filters. In ordinary practice in ventilation work it is usual to keep the sum of the duct losses }/ to ^ and the loss through the heating units at less than Yi of the static pressure. The remainder is then available for producing velocity. In the design of an ideal duct system, all factors should be taken into consideration and the air velocities proportioned so that the resistance will be practically equal in all ducts regardless of length. '. 547 HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 SIZES OF DUCTS ' The sizes of ducts and flues for gravity or mechanical circulation of air are usually based on the losses due to friction, and these losses must be kept within the available pressure difference. This pressure difference in mechanical ventilation is that derived from the fan, while in gravity ventilation the aspirating effect due to the temperature and height of the. column of heated air causes the pressure difference. Ceneral Rules The general rules to be followed in the design of a duct system are: 1. The air should be conveyed as directly as possible at reasonable velocities to obtain the results desired with greatest economy of power, material and space. 2. Sharp elbows, bends and transformation pieces should be avoided. 3. The sides of all ducts or flues should be as nearly equal as possible. (In no case should the ratio between long and short sides be greater than 10 to 1.) Procedure for Duct Design The general procedure for designing a duct system is as follows: 1. Study the plan of the building and draw in roughly the most convenient system of ducts, taking cognizance of the building construction, avoiding all obstructions in steel work and equipment, and at the same time maintaining a simple design. . 2. Arrange the positions of duct outlets to insure,the proper distribution of heat. 3. Divide the building into zones and proportion the volume of air necessary to supply the heat for each zone. 4. Determine the size of each outlet, based on the volume as obtained in the preceding paragraph, for the proper outlet velocity. . 5. Calculate the sizes of all main and branch ducts by either of the following two methods: a. Velocity Method. Arbitrarily fix the velocity in the various sections, reducing the velocity from the point of leaving the fan to the point of discharge to the room. In this case the pressure loss of each section of the duct is calculated separately and the total loss found by adding together the losses of the various sections. b. Friction Pressure Loss Method. Proportion the duct for equal friction pressure loss per foot of length. 6. Calculate the friction for the duct offering the greatest resistance to the flow of air, which resistance represents the static pressure which must be maintained in the fan outlet or in the plenum space to insure distribution of air in the duct system. The duct having the' greatest resistance will usually be that having the longest run, although not necessarily so. . Air Velocities The following velocities of air are considered standard for public buildings: 1. Through the outside air intakes, 1000 fpm. 2. Through connections to and from heating unit, 1000 to 1200 fpm. 3. Through the main discharge duct, from 1200 to 1600 fpm. 4. In branch ducts, 600 to 1000, and in vertical flues, 400 to 800 fpm. 5. In registers or grilles, 200 to 400 fpm depending upon the size and location. diffusers of proper design are used, 25 per cent higher air velocities are permissible. If These duct velocities may safely be increased 20 per cent if first class construction is used to prevent any breathing, buckling, or vibration. High velocities at one point in the system neutralize the effect of proper . , 548 CHAPTER 30. AIR DUCT DESIGN design at all other points; hence the importance of splitters in elbows and similar precautions. For industrial buildings noise is seldom considered, and main duct velocities as high as 2800 or 3000 fpm may be used where conditions will permit. For department stores and similar buildings, maximum velocities with good construction and design may be as high as 2000 or 2200 fpm in main ducts, with suitable reduction in branches and outlets. With these velocities first class duct construction is essential. One recent trend in grille design, for.all types of buildings is toward the use of much higher grille and'branch duct velocities. With proper design and installation, 1600 fpm may be entirely satisfactory. Proportioning the Size for Friction By means of Fig. 3 the diameter of branch pipes necessary to carry a given percentage of the total air in the main pipe and to maintain equal friction per foot of the length through the entire system may be deter mined. s. --I-*------------ ---------... imi.ii vv,uwuiiidu iiuwis tooeusw,an(i ltis desired to know the size of branch pipe required to carry 50 per cent of the total air in the main. Find 50,000 cfm at the right scale of Fig. 3 and move horizontally left to the diagonal line marked 60 in. Directly below this intersection it is found that the friction per 100 ft is 0.13 in. At this same friction, intersect 50 per cent capacity (25,000 cfm) and it is found that the branch pipe will be 46.5 in. in diameter. Where rectangular ducts are used it is frequently desirable to know the equivalent diameter of round pipe to carry the same capacity and have the same friction per foot of length. Table 1 gives directly the circular equivalents of rectangular ducts for equal friction and capacity, which are based on values determined from Formula 6: ' d- 1-265 ^~Tb (6) where a =* one side of rectangular pipe, feet or inches. b = other side of rectangular pipe, feet or inches. d = equivalent diameter of round pipe for equal friction per foot of length to carry the same capacity, feet or inches. To'obtain the size of rectangular ducts for different capacities, but of the same friction per foot of length, first obtain the equivalent round pipe for equal friction. Thus, if a branch of sufficient size to carry 30 per cent of a 12 x 36-in. pipe is desired, it is found from Table 1 that the main is Table 1. Circular Equivalents of Rectangular Ducts for Equal Friction 8idb ftECTANGULAB Duct 8 8.5 9 9.5 10 10.5 11 11.5 12 12.5 13 13.5 14 14.5 15 15.5 16 3 3.5 :4 ; 4.5 5 5.5 5.2 5.4 5.5 5.7 5.8 5.9 6.0 6.2 6.3 5.7 5.9 6.0 6.2 6.3 6.5 6.6 6.7 6.9 6.1 6.3 6.5 6.7 6.8 7.0 7.1 7.2 7.4 6.5 6.7 6.9 7.1 7.2 7.4 7.6 7.7 7.9 6.9 7.1 7.3 7.5 7.7 7.8 8.0 8.2 8.3 7.3 7.5 7.7 7.8 8.1 8.3 8.5 8.6 8.8 6.4 6.5 7.0 7.1 7.5 7.7 8.0 8.2 8.5 8.7 9.0 9.2 6.6 6.7 7.3 7.4 7.8 7.9 8.4 '8.5 8.8 8.9 9.4 9.5 6.8 7.5 8.1 8.6 9.1 9.6 6.9 7.0 7.6 7.7 8.2 8.3 8.7 8.9 9.2 9.4 9.8 9.9 7.8 8.4 9.5 10.1 549 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 T a b l e 1. C ir c u l a r E q u iv a l e n t s o f R e c t a n g u l a r D u c t s f o r E q u a l F r ic t io n 8-- ( C ontinued) ^(4* 1 I MN 26.4 27.5 3SSS 04 -4 040 04 40 >*"*-- o SO o^ 0< o 04 go 8533 <"4 -- 0 2288 OO O-SOOJOS --4 04 ^ 04 ^* 5?t*5S -- SO 04 00 Os Os Q^ Q^ 04 gO o O so -- 4-- 04 00 (4 <4N4 2288 -< 04 04 2; - -- -- O40O>IO oao^1 -- o -- t-- o ^ 14 4f4f4C4 <04O0<4O0rC4 f0l04 O0'4o-- 04 04 40 ^ <o t-- r-- oo oo Os 04 o- IA04 9.0 04 -4 CO^OsT -- SO-SO Os O NNC4C4 w04)s0D4 0r4T04* 8888 2233 odoo 2 7 .7 2 8 .4 29.1 , 2 9 .8 1 3 0 .3 3 1 .0 3 1 .6 3 2 .2 00^ c* O' OO 00 <004 0s o^o Os-Os^< 00 28 8283 04io0<4 0o4<0e4 04 SO a <o ' 4* t>NCO cOOl Os OC4--t4N04T4 00 4<C4 04 0^4 04 s0O4 04 --4 so i0d4r0^4c0o4c0o4 0o4s -- OO W - C4 04 00 00 *** U 2T * Mf-N traded Os P><OV)T) OMs(4(--4(o44 M9>A 04 04 04 04 04--O* 04 04 o04. o0--4 --', r.NO.04 04 04 0^4 NNNM 04 JO 25.1 2 5 .8 26.4 , 2 6 .9 1 27.5 28.1 2 8 .6 2 9 .2 A O O' OO o -- CO so tl>ODOO 2282 04 CA 40 04 04 04 04 -000-4 04 sO --sOO -04 04 to sO u>O^J os 04 W OO O > *0 04 -- 04 04 04 04 04 04 oceosoos 04 S <N 04 o*oo NNNN O O o04o04o0o4 o Os *0 0-4-4 TO Os spsplO eorosoes* s s *-- OMCOO 2228 O>*<*0 0-4 04 04 04 04 04 04 04 00 ^ os 400>^OS PA -4* TP ' <o SO 04 04 04 04 04 04 04 04 O 00 o r- t-- 00 OO 04 04 04 04 8888 C4NN)(* (4h-"IO go so 04 -4 04 go aO o 04 o-- C4'004< cer40 4 TO ^*2 MV><0<0. o.r-oOO' -4d0404*04 04 04 04 04 04 3 O U)<0 04 04 04 O '4-4 04 04 04 S04C0490H4 0A4 a (4 o -- <0 -- (422 J O'* OO MOOT) N0 Omo Os Os O -4 -4 04 04 T4 0.04 0 -- > -- *A ^. ^. 04 04 04 04040404 O o --* O04IQ04<004<004 O' 4 0s4 s04 40--4 40--4 o 0*0 OnA* (4(4(4J ec4o O -- 00 TO moot' -4 -- O -- ^ OO 04 ee-4 04 04 04 04 04 04 04 04 04 04 '0 0-0 0. -4" fl" 04 04 04 04 -- O' 04 04 04 04 S0O4 Os Os -4P OS OS O O O 0O *"J MMC4(4 hM1 0(40 4< 4Kom<o o o ooeo O *> oo * --Os 2228-8222 04 <OS 04 04 04 04 04 04 " 8222 o seOtOiO NMIOA ------ O NT4N1W sc 04 CO ^ fT4"^VS O' O' 4^ 4-- OI< OCOCOOs o-o O' Os CO ---i SO C 04 --04 --04 --04 -*>*- 04 04 es Nt'M'O 0^*00 -- ^4 d -- OO CO O' OO -- 4-- 04 00 04 -4 gOOlsO OsTC^O WOON ONON 04 4p 4l o O K C-- O Os O' CN o 8822 . o O 4*00 t-oo eo ao (4<0 0>N Os Os Os O 0^2 -- < -- I4C4A > * 40 *0 <0 <'01*1* SO O' 04 i--ao eo f- 04 00 OS Os os u) Ost-- |4N00 I^NOPJ 00 00 CO O* flO Os Os O O - 00 --- 04 04 04 04 04 sOO*A cc-oo ^-r ^ Os -- o <c <o goo >0 0-4--0- .- 4>A ot> ad oo o >)|s.04> Os Os O ------ Os04t- SA r~ -- 04 ol O* Os -- <c o -- * a ill "g OS oo< T4s<"0 tQT' U O' ON> 004^ 04 ^o0h^ 2^SSST2S"T 04^" "CO ssss <mO 550 T a b l e 1. C ir c u l a r E q u iv a l e n t s o f R e c t a n g u l a r D u c ts fo r E q u a l F r ic t io n -- (Concluded) CHAPTER 30. AIR DUCT DESIGN 551 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 F ig : 4. T y p ic a l L a y o u t o f A ir D is t r ib u t io n System CHAPTER 30. AIR DUCT, DESIGN equivalent to a 22.2 in. diameter round pipe. From Fig. 3, 30 per cent of this is a pipe 14.3 in. in diameter, and referring again to Table 1, the rectangular equivalent branch is 12 x 14 in., 10 x 17J4 in., or any other desirable combination. Since the friction chart, Fig. 3, and Table 1 were prepared, further research on duct friction under the direction of the A.S.H.V.E. Research Technical Advisory Committee on Air Distribution and Air Frictiori indicates lower pressure loss values than given in Fig. 3. Included in the work by this Committee is a revision of Fig. 3 and Table 1 to bring them into conformity with recent tests. Pending acceptance by the Society of the Committee's report, the friction chart and the table on circular equivalents of rectangular ducts for equal friction presented in earlier editions of The Guide have been retained. Multiplying or dividing the length of each'side of a pipe by a constant is the same as multiplying of dividing the equivalent round size by the same constant. Thus, if the circular equivalent of an 80 x 24-in. duct is required, it will be twice that of a 40 x 12-in. duct, or 2 X 23.3 = 46.6 in. MAIN TRUNK DUCTS J A main duct with branches is generally used to convey tempered aif for ventilation purposes only. In place of individual ducts, a compara tively large main duct supplies air by branches to the room or rooms. The velocities vary according to the nature of the installation and the degree of quietness required. At the start of the run a velocity as high as 2000 fpm may be used, but this is considered the maximum for public building work, and is reduced to from 400 to-800 fpm in the risers. This duct system may be designed so that the loss of pressure in the branches is equalized in a manner similar to that previously described. ' Velocity Method The velocity method of designing a duct'system involves arbitrarily selecting velocities at various sections of the duct system with the highest velocities generally chosen at the fan and progressive'lower velocities toward the duct openings to the room. To find the total static pressure against which the fan must operate, the static pressure loss of each section must be calculated separately and the total loss found by adding the indi vidual losses of the various sections. This method requires judgment and experience in choosing the proper velocities to approach equal friction for all lengths of run but many engineers believe that the velocity method is handier to use than other methods and will give satisfactory results for most practical applications. The air velocities given earlier in this chapter are helpful in choosing proper velocities. Adjustable dampers or splitters are used to regulate air quantities delivered. In designing a system for a given pressure loss, the equal friction method is often pre ferred over the velocity method. , Equal Friction Method Example 3. Fig. 4 shows a typical layout of an air distribution system which is applicable lor ventilation of hotel dining rooms and offices. 553 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The volume of air in cubic feet per minute for the room is determined on the basis of the number of air changes per hour required. In the example shown, the room ventilated is a hotel dining room 135 ft x 85 ft x 15 ft. A 7J^-minute air change (8 air changes per hour) is assumed for proper ventilation, giving 22,935 cfm as the air required. . 22 935 The clear area of the fresh air inlet is based on a velocity of 1000 fpm or = 22.94 sq ft. If the air washer is provided with automatic humidity control, the tempering coil should raise the temperature of the entering air to 32 F. The washer with its auto matic control will then raise the temperature from 32 F to 42 F. If the washer is not provided with automatic humidity control, the tempering coil must raise the temperature of the entering air to at least 55 F to allow for some temperature drop in the washer due to evaporation. The reheating coil is selected to raise the temperature of the air from that leaving the air washer to 70 F. The air washer should have a maximum velocity of 500 fpm through the clear area, which, in this case, is 46 sq ft. For more detailed infor mation on tempering coil and air washer control, see Chapter 38. Since the plan shows a moderately short run of main duct with no risers near the fan outlet, a fan should be selected which will have the required capacity of 22,935 cfm with a maximum velocity through the fan outlet of 1400 fpm. The outlet area, therefore, should be 16H sq ft. ' The main pipe size should be selected to give a velocity-equal to or less than the velocity at the fan outlet. Choosing a 56-in. pipe with a cross-sectional area of 17.1 sq ft, the velocity in the main pipe will be 1340 fpm. Using the friction pressure loss method this 56-in. main pipe will be taken as the basisx)f calculation. Fig. 4 shows the amount of air to be handled by each section of pipe. Using the chart. Fig. 3, the pipe sizes are as shown in Table 2. The pressure at the outlets nearest the fan will be greater than at the pipes farther along the run so that the former will tend to deliver more than the calculated amount of air. To remedy this condition, volume regulating dampers should be located at the base of each riser, or in each branch duct, and adjusted for proper distribution. At points where branches leave the main it may be advisable, depending upon the nature of the installation, to install adjustable splitters similar to that shown in Fig. 4 where the main duct divides into the 58 in. X 30 in. and 50 in. X 30 in. branches. The rectangular equivalents are selected from Table 1; the width to depth proportion will be determined by construction requirements and ease of fabrication. The calcu lation of the friction is as follows: The longest run from the fan outlet to diffuser is 150 ft 0 in.; 150 ft of 56-in., pipe is equivalent to - ^ ^ ...... ..................................................................................... 32.2 diam Two 45-in., 90-deg elbows (2 X j4g5 X 8.5)._............................................................. 13.7 diam (At 1.5 centerline radius, pressure loss is 17 per cent of velocity head, Fig. 1, = 0.17 X 50 = 8.5 diame ters of duct.) Two 23-in., 90-deg elbows (2 X 2jg3 X 8.5),.............................................................. 7.0 diam Volume or Ara (era) 22,935 12,510 10,425 8,340 6,255 4,170 2,085 Table 2. Pipe Sizes for Example 3a Diameter or Pipe (Inches) 56 45 42 39 35 29K 23 Equivalent Size or Rbo- TiNomxB Ducr (Inches) 60 x 44 58x30 SOx 30 42 x 30 42 x 24 30 x 24 30 x 15 Velocity through diffusers (not shown) to be approximately 300 fpm. 554 CHAPTER 30. AIR DUCT DESIGN Two 23-in., 90-deg elbows in riser (2 X X 30)---------------------- --------------------24.7 diam (Two bad elbows in riser, each equivalent to 30 diameters of duct.) Total diameter of 56-in. pipe.77.6 1340\2 (4Q0jrJ = 0.112 in. Taking 50 diameters as one head loss, then 77 6 X 0.112 = 0.174 in. static loss in duct. Where the connection pieces are made with long easy slopes and the general work manship is good, a regain in static pressure may be deducted from the foregoing pressure loss. This can be taken as approximately two-thirds the difference in velocity pressures at the fan outlet and the last run of pipe. The velocity in the riser is 667 fpm with a corresponding velocity pressure of 0.027 in. The fan outlet velocity is 1400 fpm with a corresponding velocity pressure of 0.122 in. The regain equals % (0.122 -- 0.027) = 0.063 in. / The net static pressure loss in the duct is: 0.174 in. -- 0.063 in--------------------------------------------------------------------------------------- .0.111 in. Other friction losses are as follows: (1) Fresh air intake 1000-fpm velocity (1% heads X 0.0625)0.094 in. (2) Tempering coil loss (from manufacturer's tables)__ 0.100 in. (3) Air washer loss (from manufacturer's tables)---------------- -------------------------------0.250 in. (4) Reheating coil loss (from manufacturer's tables) 0.100 in. (5) Allowance for regulating dampers and diffusers- ________________________ 0.100 in. Static pressure loss of system0.755 in. The fan should be selected from the manufacturer's ratings which according to the Standard Test Code for Centrifugal and Axial Fans*, will deliver 22,935 cfm at a static pressure of 0.755 in. and which has an outlet area of 16J sq ft. Example 4- Fig. 5 shows an exhaust system layout for exhausting from buildings of the same type as in Example 3. Assume the air requirements based on the number of air changes per hour to be 16,800 cfm. Using a velocity of 1400 fpm in the main duct at the fan inlet, which is an average velocity for this type of system, the area of the main is 12 sq ft, which corresponds to a 47-in. pipe. Referring to Example 3, and using the chart, Fig. 3, the pipe sizes are as indicated in Table 3 for both round and rectangular ducts. Table 3. Pipe Sizes for Example 4 .Volume or Air (era) 16,800 11,550 9,450 5,250 4,200 3,150 2,100 ; Diameter or Pips (Inches) 47 41 38 ( 31 28.5 25.3 21.6 ' Equivalent Size or Reo tangular Duct (Inches) 38 x48 30x46 30 x 40 . 24 x 34 24 X 28 16x34 16x24 . Velocity through intake grilles (not shown) to be approximately 400 fpm. *See Chapters 28 and 46. 555 . HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Fig. 5. Exhaust System Layout All risers will require dampering as in Example 3. The calculation of the friction is as follows: The longest run from the intake grille to fan inlet is 100 ft. (1) Duct friction 100 ft of 47-in. pipe ~) ------------------------------ ------" 25 6 dlam Two 2834-in,, 90-deg elbows in riser ^ 2 x X 30 ^------------------------------- 36.4 diam (Two bad elbows in riser each equivalent to 30 diameters of duct.) One 28J4-in., 90-deg elbow in horizontal run /28 5X8 5j\............ ............. ........ 5.2 diam Total diameter of 47-in. pipe.------ :-------------------------------- .-------~---------- 67-2 dlara 1400\2 4005/ = 0-122'n` (67 2 X 0 122 Taking 50 diameters as one head loss, then --1----- -.------------------------- 0164 ln- (2) Intake loss from grille (1 J4 heads at a 400 fpra velocity 134 x 0.01)------------ 0.015 in. (3) Loss occasioned by step-up of velocity (0.20 X 0.122)--------------------------- :... 0.024 in. (This loss varies from 0.05 to 0.40 velocity head depending upon the nature of the change. For average systems 0.20 velocity head is a close approximation.) (4) Square elbow turned into fan (1.0 head at 1400 fpm velocity)...... .......... -- 0122 m- Static pressure loss on inlet side------------------------------------------------------ -------- 0.325 in. To this must be added the resistance on the discharge side of the fan. A fan outlet velocity of approximately 1500 to 1600 fpm may be used. Assuming the fan outlet to be equivalent in area to a 45-in. pipe, the velocity is 1525 fpm. 556 CHAPTER 30. AIR DUCT DESIGN Loss on discharge (15 ft from fan outlet to discharge): 15 X 12 45 4 diam of 45-in. pipe. The velocity head corresponding to a velocity of 1525 fpm is 0.145 and the discharge . 0.145 X 4 . side loss is --------- -- 0.012 in. The total static pressure loss of the system is then: 0.012 + 0.325 = 0.337 in. The fan will be selected to handle 16,800 cfm at a static pressure of 0.337 in. and to have an outlet velocity of 1525 fpm. Outlet area 11 sq ft. The method of design used in Examples 3 and 4 is the equal friction method described under the heading Procedure for Duct Design. After the friction for the longest run of duct is determined, the size of the sub-branches may then be calculated based on the friction for the longest length of run to approach equal friction for all lengths of run. After the total air quantity and the size of fan are ascertained, the main duct is usually fixed as being at least equal in area to the fan outlet, or perhaps 10 per cent greater. From this main pipe all others are propor tioned. For example, if the main duct is 30 in. in diameter, a branch to carry 10 per cent of the total capacity should be 12.7 in. in diameter (see Fig. 3) in order to have the same friction per foot of length, while one carrying one-half the total capacity of a 30-in. main with the same friction loss per foot would be 23.4 in. in diameter. By this method of equalizing friction it is unnecessary to consider the resistance of each section of pipe independently, but only to know the distance from the fan outlet to the . end of the longest run of pipe, the number and size of elbows, and the diameter and velocity in the largest pipe. Frequently the problem of sound prevention in a heating, ventilating or air conditioning system imposes more severe restrictions than the pre vention of excessive pressure drop. Tendencies toward higher duct velocities have produced noise control problems which require con sideration of enumerable factors in air duct design. Naturally some types of occupancy and application permit relatively higher sound levels to be maintained than others, but the design trend is progressively directed towards noise reduction wherever possible. Sound absorbent materials have been successfully applied to duct construction to reduce noise. The basis used for the selection of the proper amounts of absorbent materials will be found in Chapter 31. DUCT CONSTRUCTION DETAILS If panel construction is used with standing seams or similar reinforce ment, and the panels are cross-broken to give rigidity, there is less likelihood of vibration due to air flow, or deflection due to air pressure. Elbows made without splitters, and improperly shaped transformation sections produce high local velocities which are the cause of noise in duct work. The use of first class duct construction with well designed trans formation sections and splitters in elbows tends to maintain relatively uniform velocities with decrease in turbulence and in the noise produced. 557 HEATING' VENTILATING AIR CONDITIONING GUIDE 1940 sheet Fig. 7. Details op Seams Heating Unit Fig. 9. Installation of Easement ' in Duct Around Obstruction 558 CHAPTER 30. AIR DUCT DESIGN Table 4. Sheet Metal Gages for Rectangular Duct Construction Gash Width or Duct Seah Rimroaczo Scam 26 24 . 22 22 20 Up to 12 in. 13 in. to 30 in. 31 in. to 48 in. 49 in. to 60 in. 61 in. to 90 in, . .. i i H in. x 1% in. 1H H in. X 1% in. If panels are not cross-broken two gages heavier material should be used. Table 5. Weights of Sheet Metal Used for Duct Construction U. S. Std. Gaob 30 28 26 24 22 20 . 18 16 14 12 10 Approximate Thicxnsbs In. 0.0120 0.0149 0.0179 0.0239 0.0299 0.0359 0.0478 0.0598 0.0749 0.1046 0.1345 Sheet Steel Weight per Square Foot Ounces 8 10 12 16 20 24 32 40 50 70 90 Pounds 0.5000 0.6250 0.7500 1.0000 1.2500 1.5000 2.0000 2.5000 3.1250 4.3750 5.6250 Galvanized Iron Wright per Square Foot Ounces 10.5 12.5 14.5 18.5 22.5 26.5 34.5 42.5 52.5 72.5 92.5 Pounds 0.656 0.781 0.906 1.156 1.406 1.656 2.156 2.656 3.281 4.531 5.781 Table 6. Weights and Thicknesses of Standard Copper Sheets Rolled to Weight Weight per Square Foot Ounces Pounds Thickness, Inches Decimal Equivalent Nearest Fraction 10 12 14 16 18 20 24 28 32 36 40 . 44 48 56 64 0.625 0.750 0.875 1.000 1.125 1.250 1.500 1.750 2.000 2.250 2.500 2.750 3.000 3.500 4.000 0.0135 0.0162 0.0189 0.0216 0.0243 0.0270 0.0324 0.0378 0.0432 0.0486 0.0540 0.0594 0.0648 0.0756 0.0864 Hi H4 Hi H2 H2 Hi H2 H2 Hi Hi Hi He He Hi Hi Variations from these weights must be expected in practice. 559 Nearest Gage No. B. & s. Stubs 27 29 26 27 25 26 23 24 22 23 21 22 20 21 19 20 17 19 16 18 15 17 15 17 14 16 13 15 11 14 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Acceptable construction details for rectangular ducts, elbows and transformation pieces are shown in Figs. 6 to 10. Other methods are also acceptable, such as the use of angle iron stiffeners for large ducts. Good ' duct construction is essential to the elimination of duct noises and for the purpose of insuring a sturdy and properly braced installation. An isometric view of a duct showing the location of the stiffening seams on the top and side panels is shown in Fig. 6. The cross seams should not occur at the same place but should be staggered as indicated. In Fig. 7 will be found a number of typical duct seams. Standing seams are used in joining the longitudinal sheets of ventilation and air conditioning ducts where they are so large that longitudinal seams are necessary. A hammered lock seam is used in ventilation work, for example, in joining rectangular elbows of offsets to their heels and throats. Countersunk grooved seams have application in duct construction where it is desired to have the outside surface smooth and flush. Heating units should be installed as shown in Fig. 8 with the duct connections making an angle of not less than 45 deg, but preferably 60 deg. Whenever a pipe or other obstruction passes through a duct an easement should be placed around the pipe as indicated in Fig. 9. Fan discharge connections should have a maximum slope of 1 in 7, as indicated in Fig. 10. -jjj The recommended gages for rectangular sheet metal duct construction are given in Table 4. Weights qf sheet metal per square foot of surface for different gages are given in Table 5. . In calculating the weights of duct, it is considered good practice to allow 20 per cent additional for weights of joints and bracings. Various weights and thicknesses of standard copper sheets will be found in.Table 6. REFERENCES Fan Engineering, Buffalo Forge Co. Heat Power Engineering, by Barnard, Ellenwooil, and Hirshfeld, Part III. Mechanical Engineers' Handbook, by Lionel S. Marks,_McGraw-Hill Book Co. The Flow, of Liquids, by W. H. McAdams (Refrigerating Engineering, February, 1925, P. 279). ` '. ............................ A Study of the Data on the Flow of Fluids in Pipes, by Emory Kemler (A.S.M.E. Transactions, Hydraulics Section, August 31, 1933, p. 7).. ' 560 Chapter 31 SOUND CONTROL Decibel Defined, Apparatus for Measuring Noise, Problem of Sound Control, Acceptable Noise Levels, Controlling Vibration from Machine Mountings, Controlling Noise through Room Wall Surfaces, Noise Transmitted Through Ducts, Duct Lining . Factor IN ventilating and air conditioning a building or a room, the effect of the mechanical system employed must be considered on the acoustics of the space conditioned. It is important to consider also that the use of air conditioning often permits keeping the windows closed, thus giving relief from certain external noises, but at the same time increasing the necessity of providing adequate sound control. It is not assumed that the ventilating and air conditioning engineer will attempt to improve the acoustics of the space that is being con ditioned, but the designer should have at least enough fundamental knowledge of the acoustical effects of the system which is being designed to be sure that no damaging effects occur to the existing acoustical properties. It is assumed that in a given space the architect and acoustical engineer have produced a room or rooms which are satisfactory for speech, music, or other uses. The ventilating engineer's sole function is to ventilate and air condition these rooms properly so that they will be physically comfortable without adding any acoustical hazards. UNIT OF NOISE MEASUREMENT By a recently adopted international standard, two terms are used for noise measurement. The decibel (db) is the physical unit for expressing intensity or pressure levels. The phon is applied to what was formerly called loudness level; that is, the equivalent level in decibels of the equally loud thousand cycle tone. The decibel is defined by the relation N = 10 logio "v", where N is the number of decibels by which the intensity i ^ flux Ii exceeds the intensity flux 70. The intensity flux is the measure of the energy contained in a sound wave and is defined in terms of micro watts per square centimeter of wave front in a freely traveling plane wave. It is usually more convenient to select an arbitrary reference intensity for Ia and express all other intensities in terms of decibels above that level. For this purpose the threshold of audibility for the average human ear at a frequency of 1000 cycles per second has been selected. This reference threshold is 10-16 watts, per square centimeter or 10"10 microwatts per square centimeter. This reference level also corresponds to a pressure of 0.0002 dynes per square centimeter. A stated sound level in decibels, unless otherwise defined, will thus be related to a threshold of 10~16 watts. For example, a level of 60 db above 561 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 this reference threshold is 10'10 watts. In a similar manner, when sound measurements are given in actual intensity or energy units, they can be converted to decibels by this relation. Since the decibel is a ratio, it can only be employed when related to a reference threshold level as given. Noise levels, which vary with fre quency as well as intensity, must not only be related to this reference threshold level, but also to a reference frequency, which is taken as 1000 cycles. These terms and procedures may be found in Tentative Standards1 published by the American Standards Association. APPARATUS FOR MEASURING NOISE Since the relative loudness to the ear, rather than the actual physical intensity, is the quantity in which engineers are usually interested, it has been found necessary to allow for the varying sensitivity of the ear at different frequencies in designing noise measuring equipment. The most satisfactory method of measuring noise is by means of a sound level meter which usually consists of a microphone, a high gain audio-amplifier, and a rectifying milliammeter which will read directly in decibels. This meter is calibrated to give readings above the threshold of audibility and usually contains a weighing network to make it less sensitive at those frequencies where the ear is less sensitive. For complete specifications relative to the approved type of sound level meters refer to the information* published by the American Standards Association. GENERAL PROBLEM OF SOUND CONTROL As previously stated, the function of the ventilating and air con ditioning engineer is to add no acoustical hazard to the conditions already present in the room or building and the problem can be stated as: a. To determine the noise level existing without the equipment. b. To ascertain the noise level which would exist if the equipment were installed without sound control. . c. To provide as a part of the installation sufficient sound control appliances to reduce the noise level substantially to that found in (a). To accomplish this the engineer should have information of three kinds: 1. A knowledge of the noise levels currently considered acceptable in various rooms in order that he may have a basis on which to proceed. 2. A knowledge of the nature and intensity of the noise created by the various parts of the equipment. 3. A knowledge of how, when necessary, to vary and control the noise level between the equipment and the conditioned space. In addition, the engineer should have information available to deal with noises which may enter the room due to openings made into it to accom modate the equipment, such as cross talk between rooms connected with common ducts and noise transmitted to portions of duct system outside the conditioned space and through to its interior. While the general problem may be logically outlined and the items of American Tentative Standards for Noise Measurement, American Standards Association. 'American Tentative Standards for Sound Level Meters for Measurement of Noise and Other Sounds, American Standards Association. 562 CHAPTER 31. SOUND CONTROL knowledge necessary to its solution can be listed, the available infor mation at present is lacking in certain respects. However, attention may be directed to that information which is currently available, and to furthermore outline a solution of the noise problem based on these data. ACCEPTABLE NOISE LEVELS Measurements of noise levels have been observed by several investi gators in various rooms and locations. The information compiled in Table 1 is based on these data, which represent the best opinion on the Table 1. Typical Noise Levels Roous Noi no Level in Decu1EL8 ro be Anticipated Min. Representative Max. Sound Film Studios.................... .......................................... 10 14 20 10 14 20 Planetarium., ................................. :..................................... 15 20 25 Residence, Apartments, etc..... - ..................................... 25 35 40 Theatres, Legitimate, ........ .. .-..................................... 25 30 35 Theatres, Motion Picture..,............................................... 30 35 40 Auditoriums, Concert Halls, etc___ ___________ _______ 25 30 40 Churches,...... .......... ...................... .. ............................. 25 30 35 Executive Offices, Acoustically Treated Private Offices 25 33 40 Private Offices, Acoustically Untreated., _ _____ 35 45 50 General Offices.... .................... ......... .................... 45 55 60 25 40 56 Class Rooms,......... .. . . . , ___ 30 35 45 Libraries, Museums, Art Galleries 30 40 45 Public Buildings, Court Houses, Post Offices, etc------- 45 55 60 Small Stores. ,, , ............................................. 40 50 60 Upper Floors Department Stores.__________ ._________ 40 50 55 Stores, General, Including Main Floor Dept. Stores.,., 50 60 70 Hotel Dining Rooms........ .... .......... ............. 40 50 60 Restaurants and Cafeterias. ......................................... 50 60 70 Banking Rooms.,,,............................................................... 50 55 60 60 70 80 Office Machine Rooms. ,, _______________ _________ 60 70 80 VEHICLES Railroad Coach................................. .................................. 60* 70 80 Pullman Car...... ......... .......... .................. ........................... 55* 65 75 Automobile.................................................................. ........... 50 65 80 Vehicular Tunnel................................................................... 75 85 95 Airplane.......... ....................... ......................................... . 80. 85 100 &For train standing in station a level of about 45 db is the maximum which can ordinarily be tolerated. subject now available. All levels are given in decibels above a reference threshold of 10"16 watts (corresponding to a pressure of 0.0002--dynes per square centimeter). Minimum, representative, and maximum levels are given for each application. These values are intended to indicate the variation which may be expected in different locations of the same type, but not the time variation which may be expected in each location. The values shown in Table 1 are typical of those found currently in 563 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 existing spaces. They are, however, the noise levels of the room and not the noise levels of the ventilating or air conditioning equipment. . If the' noise level at the room of the equipment is kept at the levels shown in the table.the equipment will not add to the acoustical hazard existing without it, provided the equipment noise is heard alone, but if both are heard together the total noise level in the room will be increased about 3 db. This is usually considered an acceptable result. In some cases it is desirable to keep the equipment noise level at the room at such a value that it actually will not increase the noise level in the room to any measureable degree. This can usually be accomplished if the equipment noise at the room can be kept 10 db below the noise level shown in the table. NOISE CREATED BY EQUIPMENT Information concerning the noise levels created by ventilating and air conditioning equipment such as fans, motors, air washers, and similar items is not yet on a basis which permits tabular presentation although certain manufacturers are prepared to offer such data and do state the noise producing properties of their products. Absence of this information makes it necessary to resort to indirect means in solving certain problems and also prevents a direct logical solution. '1 KINDS OF NOISE To solve a sound problem of this type it is desirable to consider sepa rately the several means by which noise reaches the room. This avoids to some extent the necessity of knowing the noise'level at the source and places the emphasis on ascertaining the level at the point where the sound enters the room rather than on its point of origin. The noise introduced into a room or building by ventilating or air conditioning equipment may be divided into- two-kinds depending on how it reaches the room as: 1. Noise transmitted through the building construction. 2. Noise transmitted through the ducts. It is convenient to further sub-divide these two methods of delivery as: 1. Noise transmitted through the building construction. a. From machine mountings as vibration. b. From equipment through room wall surfaces. - 2. Noise transmitted through the ducts. a. From equipment such as sprays, fans, etc. b. From outside, and transmitted through duct walls into air stream. c. From air current, including eddying noises. d. Cross talk and cross noises between rooms connected by the same duct system. The next step in the solution of this problem is to present data and discuss methods whereby solutions to the noise problem can be obtained when the allowable room noise level and the path through which the noise reaches the room are known. 564 CHAPTER 31. SOUND CONTROL NOISE THROUGH BUILDING CONSTRUCTION It is impossible to select ventilating equipment which will operate without producing some mechanical noise, and since the equipment must be mounted in a building, it is probable that a part of this noise will be transmitted to the building itself to such a degree as to make noisy con ditions in the rooms which are to be air conditioned. Much of this noise may be transmitted by the duct if it is rigidly connected to the fan outlet. It is common practice to make the connection between the fan and the duct with a canvas sleeve which effectively restricts noise at this point. Noise may also enter the building through the mounting of the motor and the fan. Flexible mountings should be provided in all installations but these mountings must be carefully designed so that they will actually reduce the contact between the machinery and the supporting floor. If a flexible material is used, it is desirable to investigate the installation so that it is not short-circuited by through bolts which are improperly insulated and by electrical conduit which is not properly broken arid is, attached both to the equipment and to. the building. The flexible mounts ing, if it is improperly engineered, may actually increase the contact between the equipment and the floor upon which it is supported. In general, the flexible. material should be loaded as heavily as possible without impairing its load-carrying capacity. Controlling Vibration From Machine Mountings The theory of the insulation of vibration was first worked out by Soderbergh If a machine of mass m be supported by an elastic pad the amount of vibratory force communicated by the machine to the floor or foundation upon which it rests will be determined by the elastic and viscous properties of the pad. The ratio of the vibratory force communi cated to the floor or foundation with the machine resting upon the pad, and with the machine resting directly upon the floor, is given by the following equation: where + 4ic*nc (? 1 \2 2xnm -- ----- ) 2xnc/ u) x' = the so-called transmissibility of the support. c = the compliance (that is, the reciprocal of the force constant), r = the mechanical resistance owing to the viscous forces within the support, n = the frequency of vibration generated by the machine which is to be insulated, such as the commutation frequency of a motor or the blade frequency of a fan. m = the mass of the machine to be insulated. It should be noted that not only must vibrations within the audible range of fre quencies be considered, but those in the sub-audible range as well, since these may cause objectionable vibrations. All the possible frequencies should be considered in the calcu lation. Sometimes beat effects are introduced by slight irregularities of belts or pulleys that have much lower frequencies than those of the rotating elements. *C. R. Soderberg, (The Electric Journal, January, 1924), and succeeding articles. See also V. O. Knudsen, (Physical Review, Vol. 32, 1928. p. 324), and A. L. Kimball, (Journal of the Acoustical Society of America, Vol. 2, 1930, p. 297). 565 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 If r, the mechanical resistance, is very small, Formula 1 may be written 1 where o is the natural frequency of the machine upon the elastic pad, (2) In most cases of design of resilient machine mounting the effect of frictional resistance is small, and Equation 2 may be used. In such cases it is only necessary to know the natural frequency of the elastic pad or platform used under the desired loading and the transmissibility for any vibrational frequency of the machine may be obtained. However, this formula gives the theoretical maximum insulation which may be obtained and should be used with a liberal factor of safety. (A factor of 2 is common practice when the ratio is converted to decibels.) If the pad is to be of any value in the prevention of solid-borne vibra tions, the value of t' must be considerably smaller than unity. If the fundamental frequency of vibration generated by the machine happens to coincide with the natural frequency of the mass of the machine resting on the elastic pad, a condition of resonance will be established, and the machine will exert a greater force upon the foundation than it would if the pad were completely removed. It is necessary, therefore, that the elastic support be sufficiently compliant, and the mass of the machine Table 2. Compliance and Resistance Data for Typical Specimens of Flexible Materials2 The compliances and resistances given in the table are for specimens 1 in. thick and 1 sq cm in cross-section Material Description or Matebial Approximate Upper Safe Loading in Pounds per Squabs Inch Compliance c in Centdcxtebb peb Dtnb Rebibtancb- r in Absolute Units Corkboard Corkboard Fiber Board Fiber Board Fiber Board Fiber Board Fiber Board Anti-Vibro-Block Sponge Rubber Soft India Rubber 1.10 lb per board foot 0.70 lb per board foot 1.35 lb per board foot Carpet lining Insulating board Insulating board Insulating board . ... 25 lb per cubic foot 55 lb per cubic foot 12 8 4 to 6 10 12 15 15 5 1 to 3 3 to 6 0.25 x 10"* 0.50 x 10~* 0.60x10-* 0.40 x 10-* 0.18 x 10-* 0.16 x10-* 0.12 x 10-* 0.60 x 10-* 3.0 xl0-` 1.2 xlO-* 0.15x10* 0.25 x 10* 0.50 x 10* --------------- - 1.5x10* From Architectural Acoustics, by V. O. Knndsen, p. 278. 566 CHAPTER 31. SOUND CONTROL sufficiently heavy, that the natural frequency of the mass m upon its elastic support will be low in comparison with the frequencies which are generated by the machine. Thus, if the principal vibrations in the machine be of the order of 100 vibrations per second, the natural frequency of the machine mounted on its elastic support should not exceed about 50 vibrations per second, and for best results preferably 20. When the forced frequency is low, it is frequently impossible to insulate for the fundamental forced frequency due to connecting pipe work and other relevant factors. In cases of this kind an effective installation of sound insulation may be obtained with a mounting which functions far above the fundamental forced frequency. For example, a compressor operating at 500 rpm has a forced frequency of 8.3 vibrations per second. By designing a mounting having a natural frequency of 20 to 25 vibrations per second, it is possible to isolate practically all of the noise. The elastic support under the machine acts as a low-pass filter which passes all frequencies below about two times the natural frequency of the machine mounted on its elastic support, but prevents all frequencies V-above about mc from reaching the solid structure of the building. The principal influence of the internal mechanical resistance r is to limit the vibration at the resonant frequency. If the values of c and r for a flexible material be known, it is possible to calculate, by means of Equation 1, the amount of insulation that will be obtained from the use of this material as a flexible support for a piece of equipment having a mass m. For the routine calculations in practice, r may be neglected with only a slight sacrifice of accuracy. Table 2 gives the values of c and r for a number of commonly used flexible materials. Example 1. A machine weighing 1000 lb has a base area of 20 sq ft. Assume that the principal vibration of the machine has a frequency of 100 cycles per second (most machinery vibrations are less than 150 vibrations per second, and the assumed frequency of 100 is quite representative of typical machines). Suppose that a 1-in. slab of corkboard weighing 1.10 lb per board foot be placed between the machine and the floor. The loading on the cork will then be only 50 lb per square foot, or slightly more than lb per square inch. (It is assumed that the compliance c in centimeters per dyne for a specimen 1 in. thick and 1 sq cm in cross-section is 0.25 X 10"` and the resistance r in mechanical ohms is 0.15 X 10*.) The transmissibility is calculated in the following manner: Mass of machine in grams = 1000 X 454 = 4.54 X 10*. Area of base in square centimeters = 20 X 144 X 2.54 X 2.54 = 1.86 X 10*. Therefore, the compliance of the entire support, 1 in. thick and 20 sq ft in cross section, is 0.25 X 10-* X ^ gg ^ i(jT = 0.134 X 10~w cm per dyne. no by Equation 2: 2* ]f 4., 1 54 X 10s X 0.134 X 10-`" 64.5 cps 100* -1 64.5* 1.41 = 0.71. Consequently it will be seen that the transmissibility is not far below unity and that the support is not satisfactory for insulating 100 or fewer vibrations per second. 567 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 . If the amount of cork be reduced so that it is loaded to 10 lb per square inch, the total area of the supporting cork wilj be only 100 sq in. or 645 sq cm. The compliance of the entire support will now be 0.25 X 10-' X srr = 0.39 X 10-8 cm per dyne. 2* y 4.i 1 = 11.98 cps .54 X 10s X 0.39 X 10-8 by Equation 2: 1 100' -1 11.98* 1 69 = 0.0145. In the first case the decibel reduction produced by the mounting, as compared with the vibration transmitted with the machine mounted directly on the floor is: 10 login = 10 logio -- - 3 db. Dividing by 2 to allow a suitable factor of safety, the gain is 1.5 db which is negligible. In the second case, the decibel reduction is: 10 login t* = 10 logic = 36.8 db. Dividing by 2, the probable isolation is of the order of 18.4 db, which is an acceptable figure. . These two numerical examples will serve to show not only the manner of making the calculations, but also the importance of selecting the proper type and design of flexible supports for insulating the vibrations of a machine from the rigid structure of a building. Controlling Noise Through Room Wall Surfaces The ventilating equipment is usually housed in a separate room where the noise produced by the mechanical operation of the equipment can be isolated from the rest of the building. If the vibration of the machinery is absorbed by flexible mounting and is not transmitted to the building, the only noise to be eliminated by the walls of the room will be the air borne mechanical noise. Acoustical measurements on average brick, tile, lath, and plaster walls indicate that the usual wall of these types is sufficient to satisfactorily attenuate this air-borne mechanical noise4. Attention should be given to the equipment room door, since this door may leak badly and allow sound to escape into parts of the building which should be quiet. Where the equipment noise is particularly severe, double doors should be used and in all cases, the doors of the equipment room should be fitted with tight thresholds and weather-stripping. The door itself may transmit considerable sound if it is thin but it will not transmit a tenth as much as will be transmitted by a )4-in. crack between the door and the threshold. In cases where the equipment noise is extraordinarily high, it may be necessary to treat acoustically the walls and 'ceiling of the equipment room. If the equipment room is not entirely closed, partition walls may be necessary. 4Acoustical Problems in the Heating and Ventilating of Buildings, by V. O. Knudsen (A.S.H.V.E. Transactions, Vol. 37. 1932, p. 211). 568 CHAPTER 31. SOUND CONTROL NOISE TRANSMITTED THROUGH THE DUCTS After noise reaches the air stream in the ducts it can be controlled by lining the ducts on the inside with a sufficient quantity of sound absorbing material. Lagging material of similar characteristics placed on the out side of ducts serves to prevent noise originating outside the ducts being carried inside the ducts and into the air stream. - -. A case where outside lagging is desirable occurs when ducts originate at the fan in the equipment room and pass through this room on the way to the room being conditioned or ventilated. Unless the ducts are lined some of the mechanical noise from the equipment room air may be trans mitted through the wall of the duct, thus reaching the air stream and be carried into the room. In such cases, that portion of the duct which is exposed to the sounds in the equipment room should be lagged with material such as cork, pipe covering or other sound damping material to prevent the sound from entering the duct at this point. Numerical data are not available to permit a simple and practical calculating procedure to determine thickness of covering which should be used for this purpose. Measurements in one laboratory have shown that the loss through a sheet of No. 22 gage metal is 24 db. When a sheet of rock wool insu lation 1 in. thick and weighing 1.4 lb per square foot is added to this, the insulation value is increased to 29 db. In general, however, adding a layer of insulation or pipe covering does not materially increase the sound insulation value unless the material is dense, or unless it is surfaced with another sound impervious layer such as metal or board. Inside lining material used in the case previously mentioned would serve as an absorber of the sound transmitted through the duct walls, and thus act as a means of preventing the transfer of noise into the air stream. Inside lining may also be used in ducts to absorb noise which reaches the air stream from equipment such as fans, sprays and coils; noise due to eddying currents set up by elbows, dampers and similar obstructions; and noise trans mitted from room to room where there is a common duct system. To use the lining effectively it must be properly located, well installed and be applied in sufficient quantity to reduce the noise level of the air stream to the level desired. At present there are no wholly national or generally recognized methods of calculating the amount of duct lining necessary to accomplish a given reduction of noise level in the air traveling in a duct system; consequently some empirical method has been used. Perhaps the commonest rule of thumb is that a length of duct should be lined which is equivalent to 10 to 15 diameters. If the duct is not square, this may be interpreted to mean 10 times the average dimension. Tests have shown that this amount of lining will usually suffice to eliminate the majority of the, high frequency noise which is prevalent. Since this is the more objectionable component of the noise, and since much of the low frequency noise is usually eliminated in passing through any extended supply system, this procedure is usually satisfactory except, in severe conditions.' 'It should be noted that the lining should be installed at or near the outlet, in order to effectively reduce all sounds which may be generated in the system up to this point. A more complete method of determining the necessary length Of lining material has been described 569 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 and is available for detailed reference6. Another empirical method uses a duct lining factor evaluated by experience. Attention is specifically called to its empirical nature and to the necessity of exercising judgment in applying it. Use of Duct Lining Factor - A duct lining factor (/) giving numerical values for use at various equipment noise levels is shown in Fig. 1. When properly used with Table 1 this chart (Fig. 1) provides a solution which may be both useful Duct lining factor f Noisy Equipment Average Quiet 0 75 65 55 5 65 55 45 10 55 45 35 15 45 35 25 20 35 25 15 25 25 15 5' 30 15 5 -5 Fig. 1. Chart for Determining Noise Reduction in Decibels from Duct Lining Factor Valuesfor equipment noise are only general. Wherever possible substitute actual values as supplied by equipment manufacturer or as measured. and simple. It is important to understand that the levels referred to in this chart are the average noise levels set up in the room by, the ventilating or air conditioning equipment. In the case of a piece of equipment which generates a noise level of 95 db, when the noise is measured immediately next to the machine, there might be a reduction of 15 db in passing through the duct, and a further difference of 15 db6 between the noise at the outlet supply grille and the average level in the room, leaving an effective `The Prediction of Noise Levels from Mechanical Equipment, by J. S. Parkinson {Heating and Venti~ toting, March 1939, pp. 23-26). . . `The drop between the level at the grille and the average level in the room will'be governed by the absorbing power of the room. This is expressed in sabines and is equal toSfli where a is the absorption coefficient of the-surface and s the area of that surface. The total absorbing power of the room is thus the summation of the absorbing power of the various room surfaces. For a discussion of the effect of the room absorption see Loc. Cit. Note 5. ` 570 CHAPTER 31. SOUND CONTROL level of 65 db in the room. Reductions of noise level ranging from 5 to 25 db through duct systems have been encountered without the use of sound absorbing linings and the drop from supply opening to average room level may vary from 5 to 20 db. To determine whether to use column 1, 2, or 3 in Fig. 1, in forming an estimate of the relative amount of noise generated by the system, the length of the untreated duct system and the number of bends or elbows or splitters should be considered, since the longer and the more complex the system, the more reduction of noise level will occur before the sound reaches the room grilles. Also the sound absorbing power of the room should be taken into account, since in rooms where there is a gifeat deal of absorptive material, such as rugs, draperies, curtains and furniture, there will be a higher loss between the outlet grille noise and the average room level. The ventilating engineer will have to judge whether the conditions deviate from the typical. Manufacturers' ratings on equipment should be considered in con nection with the foregoing discussion. The quantity determined involves Fig. 2. Diagram of Branch Duct Treatment Where Length is Insufficient for Adequate Absorption the noise level which will be produced in the room and the manufacturer's method of rating must be considered before allowances previously mentioned are accepted. To use Fig. 1, proceed by consulting Table 1 and determine the probable noise level already existing in the room, and, as suggested, assume that this level is satisfactory for current practice. This gives a noise level in decibels and with this enter the chart of Fig. 1. Read across the chart and determine the value of the duct lining factor (/) in the column at the left. Then multiply the smallest cross sectional dimension (inches) of the duct by this factor. The result will be the length of duct in inches to be lined to attenuate an average fan noise. If circular ducts are used, the length to be lined will be / X diameter of duct. Example g. A 7 x 30 in. duct is connected to a private office space in a quiet location. Determine the length of lining necessary to attenuate a fan noise satisfactorily. From Table 1 the noise level in this office will be 35 db. Length to be lined for noisy equipment is 22 X 7 = 154 in. Length to be lined for average equipment is 17 X 7 =: 119 in. . Length to be lined for quiet equipment is 12 X 7 = 84 in. The sound absorbent properties of duct lining are extremely important and materials which have coefficients as high as possible should be used. 571 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 This is particularly;true Qf'thecoefficients at the.lqw frequencies. ' Fig. l is based-on materials'having a noise quieting coefficient of 0.60 or more. For materials-which are less efficient a factor of safety should be added1.. Only certain sound absorbent materials among those listed in various1 publications will be found to be suitable for duct lining. In addition to a high sound absorbent coefficient a duct lining material should have a lowsurface coefficient of friction, high resistance to moisture absorption, and should be fireproof and vermin .proof. A number of building codes now specify that any sound absorbent material used.fpr duct lining shallhave no fire hazard. There are .no existing specifications on moisture resistance-hut- .the manufacturer should be required, to show that the material will not absorb sufficient moisture to cause deterioration or to. decrease the sound absorbing efficiency. .. .. . If, as is often the case, the length of duct from the main duct to a grille is shorter than the length of lining indicated by using the factor found, this duct may be sub-divided8 into smaller ducts, so that the value found may be.used as shown;in-Fig. 2. 1 . -. Example S. Assume a branch duct, as shown in Fig. 2, is 24 in. wide by 12 in. high and 42 in. long. Use a duct lining factor of 10. Case I. (No splitters). Length of lining = / X minimum dimension =* 10 X 12 = 120 in. In this case the duct should be lined for 120 in. which is obviously impossible. Cose II. (Two splitters). ' Results in 3 ducts 24 in. wide and 4 in. high. . Length of lining = / X minimum dimension = 10 X 4 = 40 in. This length of lining fulfills the space limitations of the branch duct which is 42 in. long. General Suggestions In some instances where high velocity air is used, a considerable amount of whistle is generated at the grille. This noise is obviously produced after the air leaves the duct and there is no treatment which can be installed in the-duct that will reduce this noise. The engineer must take into con sideration the type of grille which he intends to use and provide sufficient grille area so that the velocity through the.grille is reduced to a point where the grille is not too noisy. .. : Ducts serving more than one room permit-cross talk between the rooms and should be lined with acoustical material. Where the rooms are close together and the ducts short, the ducts should be sub-divided to provide ample acoustical treatment. Very often in ventilating duct work' the engineer feels that it will not be necessary to line ducts if the sound is traveling against the' airflow. This, however, is untrue since sound travels so much more rapidly than does the air in '.even high velocity systems; that it will travel as easily against-the airflow as it does with it. Sounds which are low in pitch are much harder to eliminate from a duct system than sound which is high in pitch, consequently equipment which produces low pitched sounds should be avoided as much as possible. TFor coefficients of commercial sound absorbent materials see Bulletin Acoustical Manufacturers* As sociation, 919 No, Michigan AVe., Chicago. HI. 'Patents exist covering the sub-dividing of ducts for installing sound absorbent materials. 572 Chapter 32 AIR CONDITIONING IN THE TREATMENT OF DISEASE Operating Rooms, Reducing Explosion Hazards, Nurseries for Premature Infants, Fever Therapy, High Temperature Hazards, Control of Allergic Disorders, Oxygen Therapy, - General Hospital Air Conditioning ' IN the past few years air conditioning has made considerable progress as an adjunct in the treatment of various diseases. Among the important applications are those in operating rooms, nurseries for premature infants, maternity and delivery rooms, children's wards, clinics for arthritic patients, heat therapy, oxygen therapy, X-ray rooms, the control of allergic disorders, and for the physiological effects in industry. ' ' :. OPERATING ROOMS The widest application of air conditioning in hospitals is in operating rooms. Complete air conditioning of operating wards is important because winter humidification is needed to reduce the danger of anesthetic gases, summer cooling with some dehumidification to eliminate excessive fatigue and to protect the patient and operating personnel, and finally filtering for the removal of allergens from the operating room air. Reducing Explosion Hazard .- Explosion hazards in operating rooms began with, the introduction of modern anesthetic gases and apparatus. Ether administered by the old drop method is still regarded as comparatively safe; but when mixed with pure oxygen or with nitrous oxide in certain concentrations the explosion hazard may be as great with ethylene-oxygen, or cyclopropane- oxygen mixtures1. (See Table 1.) ' During the course of ethylene anesthesia the mixture, usually 80 per cent ethylene and 20 per cent oxygen, is so rich that the danger of explosion is slight in the immediate vicinity of the face mask, but leakage of ethylene into the air may accumulate to any lower concentration, and thus introduce a serious hazard. The most dangerous period is at the end of the operation when the patients' lungs and the anesthesia apparatus, are customarily washed out with oxygen with or without the addition of ApriUnd Mari936)OPerating Room Again9` 573 by victor B. Phillips ModernHospital, 46. HEATING VENTILATING AIR CONDITIONING CUIDE 1940 carbon dioxide. Even when this procedure is omitted, it is difficult in practice to avoid dilution of the anesthetic gas with air during the normal course of breathing following the administration. In either case the mixture would pass through the explosion range and extraordinary precaution is necessary for the safety of the patient and operating personnel. Copious ventilation, from 6 to 12 air changes per hour, which is neces sary to preclude accumulation of explosive mixtures also reduces the concentration of anesthetics to below the physiologic threshold so that the surgeon and his personnel will not be affected. . The most important cause of accidents is probably static sparks which may result from accumulation of frictional charges on the rubber surfaces of the anesthesia apparatus, on woolen blankets, and on the bodies of the operators as they walk on insulated floors, when the humidity is low. Grounding the various parts of the anesthesia apparatus is not entirely Table 1. Explosive Properties of Anesthetics3 Anesthetic FoBiTCLA Densxtt Am = l Ethylene-............... -......... Propylene..................-....... Cyclopropane................... Nitrous Oxide................... Ethyl Chloride................. Ether-divinyl........ ............ Ether-diethyl................... Chloroform...................... CJU Cell, Cell, N,0 C,H,Cl (CMhO (C,IhhO CHCh 0.97 1.45 1.45 1.52 2.23 2.42 2.56 4.12 Lorn'S op Inplawmabilitt In Am tower Upper 2.75 2.00 2.40 28.6 11.1 10.3 4.00 1.70 1.85 l"i.8 27.0 36.5 In Oxygen Lower Upper 2.90 79.9 2.10 52.8 2.45 63.1 Not In ft immable 1.85 85.5 2.10 82.0 Not Infl immable Explosion and Fire Hazards of Combustible Anesthetics. Report of Investigations, V. S. Bureau of Mines. R.l. 3443, April, 1939- . effective, so long as rubber remains in use in the conventional equipment. Some form of protective grounding within the apparatus may be a partial solution. A comprehensive study of the explosion problem and of the general causes and prevention of operating room hazards, is being conducted by the University of Pittsburgh, the A.S.H.V.E. Research Laboratory, and the U. S. Bureau of Mines. In the absence of more understanding, no single safeguard can be given, but desirable precautions may be classed as follows: (1) to limit the region of the explosive gas mixtures; (2) to make all electric contacts explosion-proof; (3) to avoid building up static charges; (4) to ground those surfaces where charges may be built up; and (5) to discourage accumulation of static electrical charges by hu midity control. Operating Room Conditions Little is known about optimum air conditions for maintaining normal ' body temperatures during anesthesia and the immediate post-operative period. An anesthetized patient displays dilatation of blood vessels in the skin resulting in profuse sweating and (it has been believed) inability to regulate body temperature. From this it was concluded that all 574 CHAPTER 32. AIR CONDITIONING IN THE TREATMENT OF DISEASE anesthetized patients suffered considerable heat loss. In spite of this a recent paper2 reports little more than 0.8 F variation in the rectal tem perature during the course of the operation. The severe physiological effects, such as excessive sweating and rapid pulse, of high operating room temperatures on attendants and patients during the hot months signify the need for proper cooling. A comparison of surgeons' state ments who operate in both air conditioned and non air conditioned rooms strongly indicates lesser fatigue; and the greater recuperative power of the patient is confirmed by the previously referred to study3. Although the comfortable air conditions for the operatives are not identical with those for the patient a compromise is as a rule not difficult; with a relative humidity of 55 to 60 per cent, temperatures from 72 to 80 F are used. The work just cited, reported that 68 to 70 deg effective temperature not only furnished comfort for the operating room workers but apparently prevented exhaustion of the patient as evidenced by rapid convalescence in the recovery ward. Additional heat may be furnished to the patient locally or by suitable covering according to body tem perature in individual cases. The increasing incidence of allergies or of their recognition is becoming a factor in the operating room. Operations may be postponed on allergic patients during asthmatic manifestations through fear of complications. The removal of the allergens, therefore, is in some cases an important function of the air conditioning system. Central system air conditioning plants and unit air conditioners prove satisfactory in operating rooms when producing between 8 and 15 air changes per hour of filtered and properly conditioned air without recircu lation during the course of anesthesia. A separate exhaust fan system is as a rule necessary to confine and remove the gases and odors. Double windows are desirable and often necessary to prevent condensation and frosting on the glass in cold weather and to minimize drafts. The high air flow of 8 to 15 air changes in operating rooms is desirable for three reasons: (1) to reduce the concentration of the anesthetic to well below the physiologic threshold in the vicinity of the operating personnel, (2) to remove the great amounts of heat and sometimes moisture, from sterilizing equipment if inside the operating room, from the powerful surgical lights, from solar heat, and from the bodies of the operatives, and (3) to provide extra capacity for quickly preparing the room for emergency operations. Much can be gained by careful insulation of sterlizing equipment and by thorough exhaust ventilation of sterilizing rooms adjoining the operating rooms. A very common complication presumably traceable to operations is pneumonia. The difference in conditions between the operating room and the final hospital destination of the patient, including corridors and elevators, is conducive to post-operative pneumonia. A suggested remedy is a recovery ward where conditions closely approximate those of the operating room and in which the patients remain from one to four* * *A.S.H.V.E. Research Paper--Air Conditioning Requirements of an Operating Room and Recovery Ward, by F. C. Houghten and W. Leigh Cook. Jr. (A.S.H.V.E. Journal Section, Heating. Piptng and Air Conditioning, June. 1939, p. 3S1). *Loc. Cit. Hote 2. ` 575 p HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 days. Satisfactory conditions in the recovery ward not only hasten convalescence, but dispel the fear frequently found in patients who must undergo operations during the hot seasons*. , [.Sterilization of Air in Operating Room Of considerable significance to operating rooms and contagious wards is the use of ultra-violet radiation for sterilizing the air4. Results reported4 would indicate that the post-operative temperature rise of patients during the.first few days is in most instances caused more by bacterial contamination of the operative wound, than by the absorption of blood and; traumatized tissues.' Operating room infections, which were quite frequent; [before the installation of special ultra-violet lamps, are ap parently, being reduced,, . ' NURSERIES FOR PREMATURE INFANTS One of' the most important requirements in the care of premature infants is the stabilization of body temperature. This is because their heat regulating systems are not fully developed, the metabolism is low arid the irifants generally exhibit marked inability to maintain norinal .body, temperatures. The resistance to infection is low and mortality .rate high, . . 'Air Conditioning Requirements ' , . ,> The optimum air conditions for the growth and development of these infants were determined by extensive research7 at the Infants Hospital, Boston, Mass., .using four valid criteria, namely, stability of body temperature, gain in weight, incidence of digestive syndromes, and mor tality. Individual temperature requirements varied widely (from 72 to 100 F) according to the constitutional state of the infants and body weights. The optirnum relative humidity was about 65 per'cent, and the air movement less than 20 fpm. ' A single nursery conditioned to 77 F and 65 per cent.relative humidity was found to fulfill satisfactorily the requirements of the rnajority of premature'infants. Additional heat for weak (or debilitated) infants may be furnished in the cribs or by means of electric incubators placed . inside the conditioned nursery, and the temperature' adjusted according ! to individual requirements. In this way multiplicity of chambers arid - of air conditioning apparatus is obviated; the infants in the heated beds derive the benefit of breathing cool humid air, and the'nurses and doctors r need not expose themselves to extreme conditions. Importance of Humidity: Although external heat is an important factor in the maintenance of normal body temperature, humidity appears to be of equal or greater importance. Wien the premature nurseries at the Infants Hospital were kept at relative humidity between 25 and 50 4Report of the Committee on Air Conditioning (The American Hospital Association, 1937, p. 2). 5Air-Borne Infection and Sanitary Air Control, by W. F. Wells (Journal Industrial Hygiene, 17:253, 1925S).terilization of the Air in the Operating Room by Special Bactericidal Radiant Energy, by Deryl Hart (Journal Thoracic Surgery, 6:45, 1936). . nThe Premature Infant: A Study of the Effects of Atmospheric Conditions on Growth and on Develop ment, by K. D. Blackfan, C. P. Yaglou and K. McKenzie (American Journal Diseases of Children, 46: 1175, 1933). ., ; 576 CHAPTER 3Z AlR CONDITIONING IN THE TREATMENT OF DISEASE per cent for two weeks or longer, the body temperature became unstable, gain in weight diminished, the incidence of gastro-intestinal disturbances increased, and the mortality rose. On the other hand, continuous: exposure to air conditions with 55 to 65 per cent relative humidity gave satisfactory results over a period of years. The effect of humidity on mortality is shown in Table 2. The initial physiologic loss of body weight (loss occurring within first four days of life) was found to vary inversely with the humidity. In the old nurseries with natural humidity it aver aged 12.4 per cent of the birth weight; in the conditioned nurseries it was 8.9 per cent with 25 to 49 per cent relative humidity, and 6.0 per cent with 50 to 75 per cent relative humidity. The number of days required to regain the birth weight was correspondingly maximum in the old nursery and minimum in the conditioned nurseries under high humidity.- Maximum gains in body weight occurred in the conditioned nurseries under high humidity (55 to 65 per cent) in infants weighing less than ur i KtMAlUKE INFANTS ACCORDING TO HUMIDITY3 Infants Hospital, Boston, Mass. Unconditioned Nurseries (1923-1925) Conditioned Nurseries (1926-1929) . Cause or Death Acute and chronic infections.Congenital deformities............ Unclassified................................. All causes... Natural Humiditt Per Cent Mortality 26.5 1.2 1.2 Relative Huwditt 25-49 Per Cent 50-75 Per Cent Per Cent Mortality 9.7 0.0 4.8 Per Cent Mortality 0.0 0.7 0.0 28.9 14.5 0.7 incom'aUb>e Me. and also deaths 5 lb. '' The gains were less, under low humidity (25 to 50 per cent) in the' same nurseries, and in the' old nurseries prior to the installation of air conditioning apparatus. ' .! ' ' The incidence and severity of digestive syndromes, with diarrhea, persistent vomiting, diminishing'gain or loss of body weight, and other symptoms, were generally from, two to three times as high under low than under high humidity. . '' Summarizing, the best chances for life, in premature infants are created by maintaining a relative humidity of. 65 per cent in the nursery and by providing a uniform environmental temperature just sufficiently high to keep the body temperature within normal limits. Medical and nursing care are, of course, factors of equal and sometimes of greater importance. .' Air Conditioning Equipment .. ' Most of the installations now in use are of the central system type: providing, for filtration, for humidification and heating in cold weather,, 57?: HEATING VENTILATING AIR CONDITIONING GUIDE 1940 and for cooling and dehumidification in hot weather. A high ventilation rate, between 15 and 25 air changes, is desirable to remove odors and maintain uniformity of temperatures in extremes of weather. Recircu lation is not used extensively in these wards owing to odors and the possibility of infection. FEVER THERAPY Artificial production of fever in man is an imitation of nature's way of overcoming invading pathogenic organisms. The action may be direct and specific by destruction of the invading organism within the safe limit of human temperatures, or indirect in the case of heat resistant organisms, by general mobilization of the defensive mechanisms of the body, which retard or neutralize the activity of pathogenic bacteria and their toxins. The limits of induced systemic fever are usually between 104 and 107 F (rectal), and the duration from 3 to 8 hours at a time. The total period of fever treatment varies with the type of the organism involved from a few hours to 50 or more. The diseases which respond favorably to. artificial fever therapy are gonorrhea and its complications, (which include arthritis, pelvic in fections in women, and involvement of the eye), syphilis, chorea, infec tious arthritis (non-gonorrheal), encephalitis, and some forms of asthma. There are other conditions which show promise under this treatment; but the most striking results are seen in gonorrhea and syphilis, since the causative organisms can be destroyed at temperatures compatible with human life8. Equipment for Production of Fever Various means have been tried for producing artificial fever, including injections of various crystalloid or colloid substances, bacterial products of typhoid and malarial organisms; a number of physical methods, such as hot baths, radiant heat, diatherm, radiothermy, and in the last few years, air conditioned chambers. The relative advantages and dis advantages of various methods have been discussed, in a recent paper". The results by the use of air conditioned cabinets have not been fully explored, and it is therefore difficult to determine all the advantages and disadvantages of the value of air conditioning at this time. In the earlier studies of the Society10, temperatures were elevated more easily using saturated atmospheres. A fever therapy apparatus11 using these same principles has proved efficient as a means of inducing and maintaining fever in a body with small likelihood of burns because of the comparatively low dry-bulb temperatures. This saturation factor is in great use today where fever is created by induction currents by placing the body in an electrical field. When the optimum body tern- 'Report of the First Year of Fever Therapy Research by the Department of Industrial Hygiene. ScIkkjI of MFeedviceirnTe,heUrnaipvyerbsyityPohfysPicitatsl bMuerganhs, ,1b9y38F. rank H. Krusen and E. C. Elkins (Journal American Medical Asslo0Aci.aSti.oHn.,V1.1E2,: 1689-1696, Research AReppriol r2t9,N19o3. 96)5. 4--So. me Physiological Reactions of High Temp. eratures and Humidities, by W. J. McConnell and F. C. Houghten (A.S.H.V.E. Transactions, Vol. 29, 1923, p. 129). UA.S.H.V.E. Research Report No. 1054--Fever Therapy Induced by Conditioned Air, by F. C. Houghten, M. B. Ferderber and Carl Gutberlet (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 131). 578 CHAPTER 32. AIR CONDITIONING IN THE TREATMENT OF DISEASE perature has been reached by electrical induction, the atmosphere of the enclosure is kept at saturation to prevent heat loss, thus maintaining the patient's temperature at the desired point. Other apparatus18 which use electric heaters, centrifugal fans, and a water container for humidification have been used in the past, but the more recent trend is toward saturation with a lower dry-bulb temperature. When heat is necessary in treating legs or arms, such medium as short or long wave diathermy, infra-red, water baths, etc. have been used extensively. A recent development, a saturated atmosphere heating unit, similar to one previously described15 has proven satisfactory, because heat may be administered over longer periods which render deep heating possible without fear of burns or shocks14. Local heating has been somewhat satisfactory in relieving the painful symptoms of peripheral vascular disease. The final criteria for the use of fever therapy may be changed because of the introduction of certain drugs which appear prominent in the experimental treatment of some diseases for which fever therapy has been efficacious. High Temperature Hazards Heat disease is now classified as heat exhaustion, heat cramps, and heat stroke15. The last was formerly thought to be the result of high temperatures, but in the light of present knowledge, is considered a neuro logic defect. This inability to control temperature is most frequently seen in diseases of the nervous system, and heat stroke, therefore, is not so much a result of environmental temperatures as it is some intrinsic defect in the mechanism itself. The hazards of. high temperatures are not easily understood. It is difficult to say whether a repeated rise of 1 or 2 deg of body temperature is dangerous or whether short exposures at high temperatures are more harmful than longer exposures at lower temperatures. A new concept is evident in finding an increase in leuco cytes (white cells) of the blood in workers subjected to high temperatures. These leucocytes are defensive factors which are increased when infection . invades a body. A rise in temperature and leucocyte count indicates body defense in the presence of disease. Since a recent study16 showed that both temperature and cell count were increased, the question arises whether long exposures to very high temperatures might not cause exhaustion of these defense mechanisms. ALLERCIC DISORDERS Although there is some division of opinion over the ultimate cause of allergy, the prevailing belief is that it is due to an inherited or acquired hypersensitiveness to pollen or other foreign proteins in certain indivi- ,2Artificial Fever Therapy of Syphilis, by W. M. Simpson {Journal American. Medical Association, 105: 2132, 1935). ,3Loc. Cit. Note 11. 14Saturated Atmospheres in the Treatment of Injuries, by M. B. Ferderber {Industrial Medicine, 8: 256-259, June, 1939). l5Heat Disease: Clinical and Laboratory Studies, by M. W. Heilman and E. S. Montgomery. (Journal of Industrial Hygiene and Toxicology, 18: 651-666, November, 1936). "Air Conditioning in Industry, by W. L. Fleisher, A. E. Stacey, Jr., F. C. Houghten and M. B. Ferder ber (A.S.H.V.E. Journal Section, Hearing, Piping and Air Conditioning, February, 1939. p. 107)........... 579 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 duals who react abnormally to' the offending substance. The reaction may be induced by inhalation, eating, or absorption (through the skin) of the allergens. Some of the clinical manifestations are hay fever, asthma, eczema, and contact dermatitis. Symptoms of Hay Fever and Asthma . The respiratory tract is the site of probably the most usual allergic manifestations, the so-called hay fevers and asthma. In hay fevers, the nose and eyes are red and itchy, and there is considerable discharge. Nasal obstruction is the most common and most distressing symptom. The severity of the symptoms varies widely from day to day depending chiefly on the amount of pollen in the air. Seasonal asthma comes in attacks. The most popular theory concern ing the mechanism of action is that the offending substance irritates the nerve endings in mucous membranes of the respiratory tract, causing spasmodic contraction of the small bronchioles of the lungs, which interferes with breathing, particularly with expiration. Non-seasonal allergic disturbances are sometimes attributed tp house or street dusts, fungi, odors, animal dander, irritating gases, and heat or cold, particu larly sudden temperature changes. It is often stated in the literature that heat regulation in asthmatic individuals is likely unstable, with a tendency toward the subnormal. Many allergic cases who are ap parently well, develop their attacks when cold weather appears, or upon changing from warm to cool outdoor air. Air Conditioning Apparatus In recent years considerable effort has been directed toward the elimi nation of the principal cause of allergy from the air of enclosures by filtration or other air conditioning processes capable of removing pollens, in the hope of providing relief to individuals who fail to respond to medical treatment (desensitization or immunization). . . Paper or cloth filters, mounted in inexpensive window or floor units, prove quite satisfactory, but since dust and smoke "frequently cause asthmatic attacks, it is necessary that ;an air filter, to be of full value in the treatment of asthma, must remove all dusts and pollens regardless of size or amount. An electrostatic cleaner has proved extremely efficient in removing particles of 15 to 20 microns and smaller, besides dusts and smoke17. .. Although the chief remedial factor in the treatment by conditioned air is the filtration of pollen, a certain amount.of cooling and dehumidification appears to be desirable. A comfortable temperature between 70 and 75 F and a relative humidity well below 50. per cent proved satisfactory18. Direct drafts, overcooling or overheating are apt to initiate or aggrevate the symptoms. Limitations of Air Conditioning Methods The results obtained with air filtration or other air conditioning pro- uAir Cleaning as an Aid in the Treatment of Hay Fever and Bronchial Asthma, by Leo H. Criep and M. A. Green (journal of Allergy, 7: 120, January. 1936). ,i*The Effect of Low Relative Humidity and Constant Temperature on Pollen Asthma, by B. Z. Rappaport, T. Nelson and W. H. Welker (Journal of-Allergy, 6: 111. 1935). :580 CHAPTER 3Z AIR CONDITIONING IN THE TREATMENT OF DISEASE cesses in the control of allergic conditions are fairly comparable to those ' obtained by desensitization treatment so long as the patients remain in the pollen free atmosphere. But while specific desensitizatiori is preven. tive and in a few instances curative for all practical purposes, filtration gives only temporary relief. With rare exceptions, the' symptoms recur on exposure to pollen laden air. Moreover the usefulness of air condi tioning methods is limited because all cases are not caused by air-borne substances. Cases of bacterial asthma do not respond at all to the treat ment with filtered air. .' Despite these limitations air conditioning methods possess definite advantages in the simplicity of treatment, convenience, and under certain conditions almost immediate relief. Pollen cases are. usually relieved of most of their symptoms within 1. to 3 hours after, exposure to properly filtered air. ' ... .' , A pollen-free atmosphere is especially valuable in cases where desensiti zation has given little or no relief, and where desensitization is not advis able owing to intercurrent illness. On the whole, conditioning methods are considered to be a valuable adjunct in medical diagnosis and treat ment of allergic disorders. OXYGEN THERAPY Oxygen therapy is the principal measure employed for preventing and relieving the distressing symptoms of anoxemia, which is a deficiency in the oxygen content of the blood. Some of the more important conditions in which oxygen treatment is believed to be beneficial are pneumonias, anemia, heart affections, post-operative pulmonary disturbances, certain mental disturbances, asphyxia, asthma and atelectasis in new-born infants. . The ncessity of air conditioning in oxygen therapy arises from the fact that oxygen is too expensive a gas to waste in-the ventilation of oxygen tents and oxygen chambers. The oxygen rich atmosphere in these enclo sures is therefore reconditioned in a closed circuit by. removal of excess heat, moisture, and carbon dioxide given off, from the occupants being treated. Oxygen Tents " In oxygen tents the air enriched with oxygen is. usually circulated'by jne$ns of a small motor blower which sends the air over soda lime to' remove carbon dioxide and then over ice to remove excess heat and moisture. The concentration of oxygen in the tent is regulated by means of a pressure reducing valve and flow meter. In an inadequately copied tent, high temperatures and humidities are inevitable, increasing the discomfort of the patient and imposing an added strain on an already overburdened heart. Oxygen therapy under such conditions may do more harm than good. An ice melting rate of approximately lO lb per .hour gives" satisfactory results in patients with fever in a medium size oxygen tent. ' Oxygen tents are somewhat confining to the patient; the restless type of person.is difficult to control, and the delirious, impossible tp control. 581 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Medical and nursing care is complicated, as the tent must be opened or removed with attendant loss of oxygen. Oxygen concentrations of 50 per cent or more are difficult to maintain, and it is a problem to keep the temperature and humidity low enough in hot weather. The direct advantages are portability and low cost. . Oxygen Chambers . . The conventional oxygen chamber is an air-tight sheet metal enclosure of fire-proof construction, large enough to accommodate one or two patients. Trap doors or curtains are provided for the personnel, food and service, to avoid loss of oxygen. Glass windows in the ceiling and walls admit light from outside the chamber. The air conditioning system may be of the gravity type, or of the fan type using mechanical refrigeration or air drying agents. The gravity system includes a bank of cooling coils controlled thermostatically, which dehumidify and cool the air. The cool air falls over trays of soda lime at the bottom of the coils, to remove the carbon dioxide given off by the occupants. A heater at the base of the opposite wall warms the air to the desired temperature. Ordinary industrial oxygen is introduced from storage tanks outside the chamber and the concentration is regulated according to the prescription of the physician. The only change of air in the chamber is that taking place by air leakage through the trap doors. The chief objections to the gravity circulation system are stratification of cold air near the floor and accumulation of odors, which may require the use of activated charcoal, or an excess of oxygen fo'r dilution of the air in the chamber. The. fan circulation systems include compact extended surface coolers, heaters, and sometimes air-drying beds installed outside the chamber for the removal of moisture. The temperature and humidity requirement in oxygen therapy depend primarily upon the physical condition of the patient, and secondarily upon the type of disease.. In pneumonias, according to Bullowa19, prescribed conditions should be an effective temperature of 66-68 F, humidity of 50 per cent, air movement of not less than 50 linear feet per minute, oxygen concentration of 50 per cent, and carbon dioxide of less than I per cent. . Oxygen chambers are more comfortable than oxygen tents. The patients receive unhampered medical and nursing care, and the oxygen concentration, the temperature and humidity can be adequately con trolled at any desired level. The chief disadvantages are high initial and operating costs in comparison with oxygen tents or with the nasal catheter method of oxygen administration. The nasal catheter method is the simplest and most inexpensive of all but it may cause considerable discomfort to the patient and it is not satisfactory for continuous admini stration nor for restless or delirious patients. Moreover, oxygen con centrations greater than 40 per cent in the inspired air are difficult to maintain, although concentrations as high as 48 per cent have been obtained. 1*The Management of Pneumonias, by J. G. M. Bullowa, 1937, p. 260, 582 CHAPTER 3Z AIR CONDITIONING IN THE TREATMENT OF DISEASE GENERAL HOSPITAL AIR CONDITIONING Complete conditioning of a large hospital involves a capital investment and running expense which may not be justified. In clean and quiet districts, the requirements of almost all general and private wards during the cool season of the year can be satisfactorily fulfilled by the use of usual heating in conjunction with window air supply and gravity or mechanical exhaust. Insulation against heat and sound is much more important than humidification in winter; it will also help considerably in keeping the building cool in warm weather. Excessive outside noise and dust may require the use of silencers and air filters in the window openings. Cooling and dehumidification in warm weather are important. In new hospitals particularly, the desirability of cooling certain sections of the building should be given serious consideration. Financial reasons may preclude the cooling of the entire building, but the needs of the average hospital can be met by the use of built-in room coolers and a few portable units which can be wheeled from ward to ward when needed. Objection able noise is an important drawback to the use of self-contained units,, but the difficulty is gradually being overcome by improvements in design. In the North and certain sections of the Pacific Coast, cooling is needed but a few days during summer, while in the South, it can be used to advantage from May to October, and in tropical climates almost con tinuously throughout the year. Aside from comfort and recuperative power of the patients, cooling is of great assistance in the treatment of fevers in the new-born and in post-operative cases, in enteric disorders, fevers, heat stroke, heart failure, and in a variety of other ailments which often accompany summer heat waves. Considerable research is in progress on the influence of air conditioning upon a wide variety of diseases such as pneumonia, upper respiratory diseases, tuberculosis, arthritis, nervous instability, hyper-thyroidism, essential hypertension, skin diseases, and vascular disorders. REFERENCES Engineering in the Hospital of Tomorrow, by Charles F. Neergaard (A.S.H.V.E. Transactions, Vol. 40, 1934, p. 303). Hospitals Benefit in Five Ways from Air Conditioning, by Howard E. Bishop (Hospital Management, July, 1934). Air Conditioning for Hospitals, by John Paul Jones and Victor B. Phillips (Modern Hospital, November, 1936). Committee on Air Conditioning (American Medical Association, A.M.A. Journal, 1937: Vol. 108, p. 1531, 1708, 2209: Vol. 109, p. 945, 1802. 1938: Vol. 110, p. 1479, 155, 2603: Vol. Ill, p. 44, 1647). The Economical Hospital Plant as a Fundamental Factor in Economical Hospital Service, by James Govan (Hospitals, January, 1937). Bactericidal Radiant Energy for the Operating Room, by Deryl Hart (Archives Surgery, May, 1937, 34:874). The Extent of Air Conditioning Requirements from the Standpoint of Hospital Administration, by James Goven (Hospitals, January, 1938). 583 HEATING VENTILATING AIR CONDITIONING, GUIDE 1940 The.Sanitary Aspects of Air Conditioning, by C. P. Yaglou (American Journal of Public Health, February, \9iS). ' ............................... Comfort of Surgeons and Operating Room Personnel, by James Govan {The Canadian Hospital, April, 1938). . . , Cost Data on Air Conditioning,-by William E. Malm (Joint Committee on Air Conditioning, Skyscraper Management, July, 1938)- . Air Conditioning and the Surgical Patient, by W. McK. Craig {The Southern Surgeon, October, 1938, p. 462-4). . - Some Practical Aspects of Air Conditioning in Hospitals, by Ancel Keys {Hospitals,' April, 1939). ..... A Trustee Considers Air Conditioning, by Charles F. Neergaard {Modern Hospital, July, 1939). Infection of Air, by W. F. Wells, M. W. Wells and Stuart Mudd {American Journal of Public Health, August, 1939), 584 Chapter 33 RAILWAY AIR CONDITIONING ' Passenger Car Ventilation, Quantity of Outside Air, Method of Air Distribution, Air Cleaning, Steam or Vapor Heating . Equipment, Cooling Equipment, Humidity and Temperature Control, Power Supply, Installation and Operating Costs HE general principles of air conditioning as applied to buildings also Tapply to railway passenger cars, but due to space and weight limi tations and the severity of the service, equipment designed for stationary work is seldom suitable for car installations. Equipment for railway use must be safe, reliable, compact, light in weight, accessible for inspection and repairs, automatic in operation and in addition, have low initial, operating, and maintenance costs. To air condition a passenger car properly, ventilating, filtering, heating, cooling, humidifying, and control equipment must be provided together with an adequate power supply. Air from the interior of the car is mixed with air from the outside and passed through the air conditioning unit where it is heated or cooled, humidified or dehumidified and delivered to the interior of the car through suitable ducts and grilles. PASSENGER CAR VENTILATION In non air-conditioned cars, ventilation is accomplished by exhaust fans, roof ventilators,and open doors: and windows. This practice provides an ample supply of outside air;biit'does not prevent the entrance of smoke, cinders/and dirt. .. Quantity of Outside Air . ` An average passenger car contains approximately 5000 cu ft of air and may seat as many as 80 passengers. The occupants are continually liberating heat, carbon dioxide, moisture, odors, and some organic matter from their breath, skin and clothing. The heat and moisture can be removed by cooling and dehumidification, but the other constituents can be successfully handled only by proper ventilation and air cleansing. In the average car from 2000 to 2500 cfm should be circulated by the air conditioning unit. Some of this air may be recirculated, but a portion of it should always be brought in from the outside. The amount of outside air required depends upon the type of car, number of passengers, air temperature, humidity, odors, and whether or not occupants are smoking, and will vary from 15 to 90 per cent of the total air circulated. The per centage of outside air should be kept as low as possible to maintain the air in the proper condition in order to minimize the heat or cooling load. 585, HEATING VENTILATING AIR CONDITIONING GUIDE 1940 For normal conditions, 10 cfm of outside air per passenger is sufficient. When smoking is permitted, 12 to 15 cfm per passenger should be ad mitted. Under exacting demands and adverse condition, it may be necessary to increase the quantity to 20 cfm per passenger. Method of Air Distribution Various methods may be used to distribute the air delivered to the interior of the car by the circulating fan or blower. The methods commonly used are: 1. A duct lengthwise along the center of the car. 2. One or two side ducts built on the outside of monitor-roofed cars, or on the inside of turtle-backed or arched-roofed cars. 3. Free discharge at the end bulkheads, or by free discharge from a unit placed overhead in the center of the car, discharging toward the ends. For details of air distribution and duct design, see Chapters 29 and 30. Smoking rooms present a special problem. The cloud of smoke' that usually hangs near the ceiling can be broken up by having the incoming air directed along the ceiling in all directions at a velocity somewhathigher than that used for the rest of the car. The air should be exhausted from the room by a fan or through a grille to the washroom or lavatory, and then outside by a fan in a ventilator. For compartments an adjustable supply duct outlet grille of suitable size and design should be provided and provisions made in the door or partition for the removal of the air to be recirculated. . Lower berths in sleeping cars and office cars should be provided with an adjustable air outlet which will discharge the amount of air desired at low velocity in any direction so that the occupant can regulate the ventilation to meet his own requirements. In cars containing but one or two rooms or compartments, satisfactory results may be obtained by discharging the air directly from the con ditioning unit into the upper part of the car. Care must be taken to have a proper discharge velocity. If the velocity is too low, the air will drop before reaching the end of the car and if too high it will discharge against the end bulkhead and be reflected back. Care must be exercised to secure proper circulation, otherwise objectionable drafts will be experienced. The recirculating air grilles are usually of the straight flow type, and should be located so that objectionable drafts will not be created by the return air. The outside air intakes, located in the car vestibule, on the side of the car, or on the roof of the car, depending upon the location of the cooling coils, should be of ample size to permit the entrance of suf ficient outside air. On many of the recently air-conditioned cars, there are no dampers or shutters at the outside air intakes, the percentage of outside air being controlled by blocking the flow through the recircu lating grille. Air Cleaning All of the air circulated by the blower is filtered before passing over the cooling coils. In some cars the outside and recirculated air are filtered separately before mixing, while on others the air from the two sources is 588 CHAPTER 33. RAILWAY AIR CONDITIONING mixed before passing through a common filter. Filters in use are made of metal, wool, cloth, spun glass, hemp, paper, hair, and wire screen. Most filters have a viscous coating of oil for greater cleaning efficiency. Some types may be cleaned, retreated, and returned to service while other types are discarded when dirty. STEAM OR VAPOR HEATING EQUIPMENT The majority of cars in service are heated by circulating low pressure steam or vapor through pipes located along the side walls near the floor. When an air conditioning unit, using air from the outside, is installed it is necessary to provide a heating coil to warm the air during cold weather. Usually from 30 to 40 per cent of the heat required is supplied from the air conditioning unit and the balance from the floor heating system. It is necessary to have sufficient floor radiation to keep water lines in the car from freezing while standing in the yard with the air conditioning unit shut off. In new and some rebuilt cars, finned pipes are used for the floor heat to provide greater radiation surface. A few cars have the heating pipes enclosed in a duct, through which air is forced by a fan, the warmed air discharging through numerous openings along the floor. The amount of heat required depends upon the type and construction of the car, especially the amount and kind of insulation, outside temperature, wind velocity, train speed, number of passengers, and inside temperature de sired. In severe weather, with temperatures from --10 to --20 F, an average of approximately 200 lb of steam per car per hour is required. Pullmans require approximately 250 lb per hour, coaches 150 to 175 lb per hour and baggage cars 150 lb per hour. COOLING EQUIPMENT Three general types of cooling or refrigerating equipment are being used with satisfactory results. These are the ice-activated, the steam-ejector and the mechanical compression systems. These systems when arranged for car use, function the same as in stationary service, but must be more compact and lighter in weight. See Chapter 24 for description of the general principles of the various systems. ' The mechanical compression systems are divided into three general classes depending upon the type of drive for the compressor, namely, the electro mechanical, the direct mechanical, and the internal combustion engine mechanical. The compressor of an electro mechanical compression system is driven by an electric motor, the power for which is supplied by a generator and a storage battery. The generator is driven from the car axle by a gear, belt, or other type of mechanical drive. The compressor of a direct mechanical compression system is driven directly from the car axle by means of a mechanical drive, the speed of the compressor being regulated by an electric speed control which permits slippage at high train speeds. The compressor of the third type of mechanical compression system is driven by an internal combustion engine operating on propane. Sufficient fuel for several days' operation is carried in drums mounted in a rack under the car. The refrigerant frequently used in the-mechanical compression systems is dichlorodifluoromethane. The condensers are cooled by blowing a 587 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 large quantity of outside air over the dry condenser coils, or over the coils wet by a spray of water to .obtain the benefits of evaporative cooling. The latter method gives lower discharge pressures which is a distinct advantage when operating, at high outside temperatures. A device gaining in popularity is a liquid subcooler by means of which the liquid refrigerant is subcooled by evaporative cooling, producing more available refrigeration at the air conditioning unit. . . The capacity required in the refrigerating system depends upon a number of factors such as size and type of construction of car, thickness and kind of insulation used, the amount of heat produced within the car by motors, lights, and other appliances, the amount of outside air, the intensity of solar radiation, the number of occupants, and the inside temperature desired. The sun load on a bright day is about 1.2 tons. For average cars on sunny days, with high outside temperatures and humidities, from 65,000 to 80,000 Btu per hour will have to be removed from the interior of the car to maintain an inside effective temperature within the comfort zone. This means that a refrigerating rapacity of from 5.5 to 7.0 tons will be required. ' HUMIDITY CONTROL The temperature to be maintained in a car depends upon the outside temperature and the humidity desired inside the car. With a low hu midity it is necessary to maintain a higher temperature to establish a desirable comfort condition. Little humidity control has been attempted on cars up to the present time.' A certain degree of automatic humidity control is secured with cooling, but the relative humidity obtained depends largely on the temperature of the evaporator, which should be below the dew-point temperature of the air. With certain outside atmospheric conditions it may not be possible to operate the conventional equipment with a sufficiently low evaporator temperature to reduce the. humidity without dropping the temperature too low. One method has been developed whereby the evaporator temperature is carried below the dew point a sufficient amount to insure dehumidification and then the cold air is heated to the proper temperature by passing it over coils through which part of the high temperature liquid from the condenser is by-passed. Such a system is costly and has not been generally applied. . During the heating season humidification is desirable from a comfort standpoint, but unless properly, controlled, condensation will appear on the windows. A steam or water spray controlled by a humidistat will .provide the necessary moisture for humidification. There are several .cars with this fea'ture now in use. . TEMPERATURE CONTROL , The control of the air conditioning equipment should be simple and automatic in; order to eliminate the human element for the selection of the control point. The use of a centralized panel for all switches, fuses, relay, etc., will simplify the installation and operation. Generally, separate thermostats are used for heating and cooling control. The best location for the thermostats depends upon the car layout and method of air distribution and can best be determined for any particular type of car 588 . CHAPTER 33. RAILWAY AIR CONDITIONING . and equipment by careful consideration of the several factors involved. . The floor heat thermostats are usually located near the floor. The over head heat and cooling thermostats are placed in the upper part of the car, Sometimes in the air ducts or at the recirculating grille. All thermostats should be located so that the air can circulate freely around them. Maintenance of uniform comfort conditions for. cooling, floor and over head heating, has been satisfactory with provisions for a high, a medium, and a low thermostat setting and in some cases two settings have been satisfactory for cooling. In many cars the following points have been found to be satisfactory: 72, 74, and 76 F for cooling, and 60, 71 and 74 F for floor and overhead heating. A few cars are in operation in which the inside temperature is varied dependent upon the outside temperature in order to prevent too high a differential between inside and outside temperatures. The maximum inside dry-bulb temperature permitted by these controls is usually 80 F. The heating and refrigerating equipment should be interlocked so that they cannot both operate at the same time. While heating, the control should be so arranged that in rase of a steam failure the blower fan will stop or the outside air intake should be closed to prevent cold outside air from being introduced into the conditioned space. POWER SUPPLY One of the most important problems to be solved in connection with railway car air conditioning is that of power supply. The majority of non air-conditioned cars now in service are electrically lighted and equipped with fans. Power is furnished by storage batteries and axle generators of from 2 to 5 kw capacity. Electric Power Requirements When air conditioning is installed the electrical load is increased, according to the type of system as indicated in Table 1. To furnish this additional electric power, the rapacity of the axle generators must be increased to 4 to 20 kw, and the storage battery rapacity increased, in addition to that required by the car lighting system by 400 to 700 amp-hr for the electro mechanical system, by 150 to 300 amp-hr for the steam ejector and direct drive mechanical systems, and by 50 to 200 amp-hr for the ice-activated and internal combustion engine' mechanical.-systems. Total Power Requirements , ; : In addition to the electric power requirements, for continuous operation at average temperatures, the direct drive mechanical system requires Table 1. Electric Power Required to Operate System ' - Stbtbm . Electro-Mechanical________________ _____ _________ Direct Drive Mechanical Internal Combustion Engine Mechanical Steam Ejector.......... Ice-Activated... 589 .................... - -- .................7 Kilowatts 10.50 1.00 1.25 3.35 1.20 . HEATING VENTILATING AIR CONDITIONING GUIDE 1940 10.24 hp from the car axle and the steam ejector system requires 230 lb steam per hour from the locomotive boiler for a 6-ton unit. The iceactivated system requires 463 lb of ice per hour and the internal com bustion engine drive mechanical requires 7.3 lb propane per hour. This power, with the exception of the ice and propane, as well as the power required to move the extra weight of the equipment and the power required to overcome the axle bearing friction, must be supplied by the locomotive en route, and if a number of cars in the train are air condi tioned, the effect on train performance should not be overlooked. The demand for power for cooling comes, however, at the time of the year when steam for heating is not required, and the demand for lighting is at a minimum. _ The total power required by the air conditioning systems will vary With the speed of train operation because of the effect of speed upon the drive efficiency and upon the resistance due to the added weight of the equip ment. Fig. 1 shows the effect of speed upon the efficiency of the direct drive used with the direct mechanical system, and upon the average efficiency of four mechanical drives and generators used for electric power generation. The total increase in weight of passenger cars because of air conditioning is approximately 9,600 lb for the electro mechanical, 8,600 lb for the direct mechanical, 8,600 lb for the internal combustion engine drive mechanical, 11,300 lb for the steam, and 8,500 lb for the ice-activated system. The average refrigeration load has been found to be 3.3 tons, and the average capacity of air conditioning systems is about 5.92 tons. The relation of load to capacity, 3.3 5.92 = 0.56 or 56 per cent, is that percentage of the time during the cooling season that the cooling equip ment will be in operation. The average drawbar horsepower demand upon a locomotive, accordingly, consists of 56 per cent of the horsepower required for continuous operation and 44 per cent of the horsepower required for non-operation. Table 2 shows the drawbar horsepower that must be supplied by the locomotive for each air conditioned car for continuous operation of the air conditioning system, for non-operation of the equipment, and for an average condition when the air conditioning equipment is operating continuously 56 per cent of the time and is not operating. 44 per cent of the time. It is important not to overlook the horsepower demand on the locomotive when the air conditioning equip ment is not operating, which includes the horsepower required to operate the blower fan, to haul the weight of the equipment, to overcome drive and generator friction, and to replace the losses occasioned by the re moval of current from the storage battery. Fig. 2 shows the tractive resistance of a 75-ton passenger car with six wheel trucks without an axle generator, with a 4 kw generator load, and, for the same car with an increase in weight of 5 tons and a 20 kw axle generator load. The curve with the 4 kw generator is representative of a car before air conditioning, and the curve with the 20 kw generator and 5 tons added weight is representative of a car after air conditioning. At 50 mph, the tractive resistances of these two cars are 520 lb and 745 lb. respectively, or a difference of 225 lb. Then: ^ = 29.7 hp is required due to a 16 kw load and 5 tons added weight. Ten cars with a 590 CHAPTER 33. RAILWAY AIR CONDITIONING similar load would require 297 horsepower or roughly 10 per cent of the capacity of a 3,000 hp passenger locomotive. Consideration must also be given to the power requirements for refrigeration while the car is standing or running at slow speeds. The electrical energy required for the ice-activated, steam, and internal combustion engine drive mechanical systems is easily supplied from the Fig.'I. Efficiencies of Drive Mechanisms for Railway Air Conditioning Systems Fig. 2. Tractive Resistance of 75 Ton Passenger Car with Six Wheel Trucks storage battery. Steam for the steam system can be supplied from the locomotive or from a stationary plant. The majority of the electro mechanical systems are equipped with A. C.--D. C. motors. While standing in the yards and stations the A. C. motor is connected to a 220-volt, 3-phase circuit. The majority of these equipments are so ar ranged that, while operating on A. C. power, the D. C. motor may be used as a generator for battery charging. If an auxiliary circuit is not available the D. C. compressor motor may be operated from the storage battery for short periods of time. The direct drive mechanical compres- 591 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 sion systems are, also, equipped with A. C. motors for operation from auxiliary circuits. As these equipments can only be operated when con nected to the auxiliary circuit or while the train is running above the cut in speed of the drive, many cars are equipped with an auxiliary hold-over system by which reserve cooling is available. Due to the characteristics of the direct drive, the air conditioning system operates at reduced capac ity when the car is moving at speeds below 42 mph. Table 2. Locomotive Power Demands for Different Air Conditioning Systems System Drawbar Horsepower per Car Required at Train Speeds - 30 MPH 50 MPH | 70 MPH 90 MPH For Continuous Operation Electro Mechanical...... .......................................... Direct Mechanical.................................................. Internal Combustion Engine Mechanical. -- Steam Ejector3........................................................ Ice-Activated.-......................................................... 20.9 16.8 3.4 7.6 3.2 , 22.2 19.5 4.6 9.3, 4.5 25.4 29.5 7.0 12.5 6.8 31.6 42.6 11.9 19.0 11.6 For Non-Operation Electro Mechanical.- .......................................... 5.0 6.4 9.0 14.4 Direct Mechanical................ ................................. 5.2 6.3 8.7 13.5 Internal Combustion Engine Mechanical------ 2.2 3.5 5.8 10.6 Steam Ejector.......................................................... 3.7 5.4 8.4 14.8 Ice-Activated.... ......... ............................................. 1.9 3.2 5.5 10.2 For Average Condition of 66 Per Cent Continuous Operation and 44 Per Cent Non-Operation Electro Mechanical--..........................i................. Direct Mechanical:.................. :...................... ...... Internal Combustion Engine Mechanical------- Steam Ejector3.................... :.............. :--~-- Ice-Activated.--........1-- , 13.9 11.7 ;2.8 5.9 ;2.6 15.2 18.2 24.0 13.7 20.3 29.6 , 4.1. , 7.6 3.9 6.5: 10. T 6.2 ! 11.4 : 17.5 ' 11.0 i___ !__ In addition, steam is required from the locomotive to the extent of 230 lb per hour during the time the * equipment is in operation. : : . COST OF RAILWAY AIR CONDITIONING The cost of railway air conditioning is usually expressed in terms of 1000 car-miles. The actual costs for the different systems, however, are dependent upon a number of variables. Based upon a survey of the most prominent railroads in air conditioning, arid upon extensive tests, the values given in Table 3 are indicative of the present costs of air con ditioning to the railroads. . Gross Installation Cost The gross installation cost, from which the fixed- charges are derived, may be amortized on this basis: - 592 CHAPTER 33. RAILWAY AIR CONDITIONING Table 3. Air Conditioning Costs for Railway Air Conditioning System Gross Installation Cost Electro Mechanical............ ..... Direct Mechanical__________ Internal Combustion Engine Mechanical_____ Steam Ejector........................... Ice-Activated...... ...................... $6,484.00 8,515.00 5,750.00 8,475.00 3,982.00 Fixed Charges $ 8.65 11.35 7.67 11.30 5.31 Costs per 1000 car-miles* Maintenance Cost Operation Cost $3.33 2.33 $0.99 0.93 3.30 2.15 0.97 1.99 1.02 5.29 Total $12.97 14.61 12.96 14.47 11.57 "For an average cooling season of 5 months, an average train speed of 50 mph and an average car mileage of 150.000 miles per year. 1. Depreciation, at the rate of 12.5 per cent. . 2. Interest, at the rate of 6 per cent. 3. Taxes and insurance, at the rate of 1.5 per cent. The fixed charges per 1000 car-miles for any type of system are: FC = -- (0.20A) . (i) where FC = fixed charges, dollars per 1000 car-miles. A -- gross installation cost, dollars. m = total number of car-miles traveled in one year. ' Maintenance Cost : The average maintenance cost is based upon the experience of the railroads in maintaining several hundred air conditioning units. The maintenance cost per 1000 car-miles is: where m MC = maintenance cost, dollars per 1000 car-miles. B = total annual maintenance cost, dollars. m = total number of car-miles traveled in one year. (2) Operation Cost The cost of operation is influenced by: . 1. Speed of train operation. 2. Average drawbar horsepower required to operate air conditioning system. 3. Length of the cooling season. . .. . 4. Cost of power produced by the locomotive at 30.00493 per horsepower-hour. 5. Proportion of time the cooling equipment is operated during the cooling season considered as 56 per cent. . . 6- Cost of additional necessities as: a. Ice in bunker, at $4.42 per ton, 6. Propane on the car, at $0,039 per pound, c. Steam at $0,021 per 100 pound. The operation cost in dollars per 1000 car-miles is: 'OC=^(CX + 0.56fXG)+MM(ffX) 125 125 593 (3) HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 where OC operation cost, dollars per 1000 car-miles. D = average drawbar horsepower demand on a locomotive at speed S. E = cost per horsepower-hour, dollars. F = additional necessities such as ice, steam or propane, pounds per hour G = cost of additional necessities, dollars per pound. H = drawbar horsepower required when system is not operating. ' S -- speed of train operation, miles per hour. K = length of cooling season, months. 0.66 Proportion of operation time to total time during the cooling season. Fig. 3. Comparative Total Costs for Railway Passenger Cars Total Cost of Air Conditioning When the. fixed charges, maintenance cost, and operation cost are each expressed in terms of 1000 car-miles, addition of the three elements will give the total cost of stir conditioning on that basis. Comparisons of the total cost per 1000 car-miles for the five methods of air conditioning are shown in Fig. 3, representing costs for an. average condition, namely, a cooling season of five months and an average speed of 50 mph. REFERENCES Summary Report on Air Conditioning of Railroad Passenger Cars, by Division of Equipment Research, Association oj American Railroads, November 24, 1936. Engineering Report on Air Conditioning of Railroad Passenger Cars, by Division of . Equipment Research, Association of American Railroads, April IS, 1937.. Report on Performance and Cost of Operation of 1937 Internal Combustion Engine Mechanical Compression Equipment for Air Conditioning Railroad Passenger Cars, by Division of Equipment Research, Association of American Railroads, May 1, 1937. . 694 Chapter 34 INDUSTRIAL AIR CONDITIONING Atmospheric Conditions Required, General Requirements, Classification of Problems, Control of Regain, Moisture Con tent and Regain Conditioning and Drying, Control of Rate of Chemical Reaction, Control of Rate of Biochemical Re actions, Control Rate of Crystallisation . N the application of air conditioning to industrial processes, too much I stress cannot be laid upon a thorough understanding by the air con ditioning engineer of the problems involved. A complete knowledge of these problems is necessary before a satisfactory design can be made. Individual processes and machines are changing rapidly and air con ditions must be constantly revised to meet the new conditions. ATMOSPHERIC CONDITIONS REQUIRED The most desirable relative humidity during processing depends upon the product and the nature of the process. As far as the behavior of the material itself and its desired final condition are concerned, each material and process presents a different problem. The best relative humidity may range up to 100 per cent. Similarly the most desirable temperature may range between wide limits for different materials and treatments. Ex tremes in either relative humidity or temperature require relatively expensive equipment for maintaining these conditions automatically. In departments where people are working, their health, comfort, and productive efficiency must be considered and often a compromise between the optimum conditions for processing and those required for the comfort of the worker is desirable. .` It is generally considered that relative humidities below 40 per cent are on the dry side, conducive to low regains, a brittle condition of fibrous materials, prevalence of static electricity, and a tendency toward dryness of the skin and membranes of human beings. At the other end of the scale, humidities above 80 per cent are relatively damp, conducive to high regains, extreme softness, and pliability. Table 1 lists desirable temperatures and humidities for industrial pro cessing. In using this table, care must be taken in qualifying the process. In preparing many materials, conditions are not maintained constantly, but different temperatures and humidities are held for varying lengths of time. ' 595 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 1. Desirable Temperatures and Humidities for Industrial Processing Ikdostbi Process Automobile--------- Assembly line... Baking............... -- Cake icing___________ __________ ________ Cake mixing Dough fermentation room.......................... Loaf cooling:.................... .............................. Make-up room.................... ...................... .... Mixing room...... ............................................ Paraffin paper wrapping-.................... ...... Proof boxes..______________ ______--............ Storage of flour...... ....................................... Storage of yeast--......................................... Biological Vaccines--------- Products---------- Antitoxins------ Brewing. Fermentation in vat room--.................... Storage of grains............................ .............. Ceramic.--....... Drying of auger machine brick. Drying of refractory, shapes___ Molding room........ ................... .... Storage of clay.............................. Chemical--------Confectionery- General storage------ Chewing gum rolling................................... Chewing gum wrapping............... Chocolate covering........................ Hard candy making..................... Packing................ ...................... .... Starch room................................... Storage................ ........ ................... General manufacture........ .......... Distillery--....... Storage of grains____________ -- Drug...----- ----------Electrical....... -- Storage of powders and tablets. Insulation winding._________________ __ Manufacture of cotton covered wire-- Manufacture of electrical windings___ Storage of electrical goods_____________ Food__________ Butter making--------------- -----Dairy chill room_______ ____ Preparation of cereals._____ Preparation of macaroni----Ripening of meats------Slicing of bacon Storage of apples--................ Storage of citrus fruit______ Storage of eggs in shell_____ Storage of meats----------------Storage of sugar.l---------------- Fur. Drying of furs-----------Storage of furs------------ Temperature Degrees Fahrenheit 65 Relative Humidrrr Per Cent 40 70 75 80 70 75 to 80 75 to 80 80 80 to 90 70 to 80 28 to 40 50 65 76 to 80 60 to 70 55 to 70 55 to 70 55 80 to 95 60 60 to 75 below 32 38 to 42 ; 44 to 50 60 50 30 to 45 180 to 200 110 to 150 80 60 50 to 60 60 . . 35 60 to 80. 75 70 62 to 65 70 to 80 65 75 to 85 60 to 68 - ----- 60 60 35 to. 50 50 . 45 50 to 55 30 to. 50 50 50 50 to 65 45 30 to-45 70 to 80 104 60 to 80 60 to 80 60 to 80 60 40 60 to 70 70 to 80 40 60 31 to 34 32 . 30 Oto 10 80 30 to 35 5 60 to 70 35 to 50 35 to 50 60 60 38 38 80 45 75 to 85 80 80 . 50 35 110 28 to 40 25 to 40 596 CHAPTER 34. INDUSTRIAL AIR CONDITIONING Table 1. Desirable Temperatures and Humidities for Industrial Processing (Concluded) . IhDUSTBT Process Incubators-- Chicken------------------- ...................... Laboratory. General analytical and physical-- Storage of materials..:----.--..._ Leather.------------... |:: Drying of hides____ :__--_______ ____ __ ! Temperatubs Degrees Fahrenheit Relative Humiditt Per Cent 99 to 102; 55 to 75 . 60 to 70 60 to 70 60 to 70 35 to 50 90 Library.--______ Book'storage (see discussion in this chapter) Linoleum_________ Printing--........ 65 to 70 80 38 to 50 40 Matches Manufacturing_____________ 1________ 72 to 74 Storage of matches............:__ _____ _______ 60 50 Munitions._______ Fuse loading.__ 70 55 Paint. Air drying lacquers.---------....------------------- 70 to 90 Baking lacquers-------- .---------------------------- 180 to 300 Air drying of oil paints--........ :--------------- 60 to 90 25 to 50 25 to 50 Paper.______ I__ :___ Binding, cutting, drying, folding, gluing., Storage of paper;________________--...____ 60 to 80 60 to 80 25 to 50 35 to 45 Photographic__ Development of film_______ :--------- ---------Drying_____________________________ Printing-__ _____ ____________ _____ Cutting-------r.____________ __ ____ ------------- 70 to 75 75 to 80 70 72 60 50 70 65 Printing _ Rubber. Soap--. Binding......................... ......... l.-- ----------- --. Folding------ --------------------------------- ---....... Press room (general)------------------------------Press room (lithographic)...... ......... ......... -- Storage of rollers_________________________ Manufacturing.----------- ----------- .------Dipping of surgical rubber articles. Standard laboratory tests.--_____... Drying- 70 77 ' 75 60 to 75 60 to 80 90 75 to 80 80 to 84 110 45 65 60 to 78 20 to 60 35 to 45 25 to 30 42 to 48 70 Textile. Cotton-- carding--J J____ :------- ---- - combing._____________ _______ _ roving________ _____ ____ -- spinning...... .......................... weaving;_______ --........ ;'.-- Rayon-- spinning.___________________ ___ twisting_____________--___ i------ Silk-- dressing spinning--_____--_________ :------- throwing;........................................ weaving._______________________ Wool-- carding............................................ spinning--_: weaving. 75 to 80 75 to 80 75 to 80 60 to 80 68 to 75 70 70 75 to 80 75 to 80 75 to 80 75 to 80 75 to 80 75 to 80 75 to 80 50 60 to 65 50 to 60 60 to 70 70 to 80 85 . 65 60 to 65 65 to 70 65 to 70 60 to 70 65 to 70 55 to 60 50 to 55 Tobacco.-,:__ Cigar and cigarette making.......... .......... Softening_________________________ Stemming or stripping------------------------ 70 to 75 90 75 to 85 55 to 65 85 70 597 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 CENERAL REQUIREMENTS In general, air conditioning apparatus for industrial purposes must be capable of absorbing heat from various sources such as machinery power, electric lights, people, sunlight and chemical reaction; of warming or cooling to any desired temperature, and of providing ample air supply at all times. Refrigeration may or may not be required, depending upon natural conditions, the required relative humidity and the maximum permissible temperature. Washing, purifying and recirculating of the air may be desirable. Good distribution is essential for the control of air motion and for the prevention of uneven conditions. Accurate, sensitive and reliable automatic control of humidity or temperature, or both, is vital in most cases. Ordinarily, outside weather conditions and the ventilation required for workers are. of secondary importance in relation to the total work to be done by the air conditioning system. In extreme cases of high concentra tion of industrial heat from machinery and ovens the error of entirely omitting the heat gain through the building structure would not be serious. At the other extreme, where low temperatures must be produced with refrigeration and where comparatively little power is used for driving the machinery, the heat gain through the building structure will become the major factor in determining the size of equipment and in this case the ventilation requirement assumes a normal degree of .importance. Buildings which are to be air conditioned should therefore be designed with careful consideration of over-all cost and efficiency. Condensation resulting from high humidities must be prevented by suitable materials and construction, or else collected and drained to prevent loss of product or quick deterioration of the structure. Air leakage or filtration may add greatly to operating costs or make the maintenance of low humidities (relative or absolute) wholly impossible. Low temperatures require good insulation. It is apparent that the subject of air conditioning for industrial processes is extensive and greatly involved, and that a detailed treatment is there fore beyond the scope of this book. A few of the salient points of the general subject are covered in this chapter. CLASSIFICATION OF PROBLEMS In general, any industrial air conditioning problem may be listed under one or more of the following four classes: 1. Control of Regain. 2. Control of Rate of Chemical Reactions. 3. Control of Rate of Biochemical Reactions. 4. Control of Rate of Crystallization. CONTROL OF REGAIN In the manufacture or processing of hygroscopic materials such as textiles, paper, wood, leather, tobacco and foodstuffs, the temperature and relative humidity of the air have a marked influence upon the rate of production and upon the weight, strength, appearance and general 598 . CHAPTER 34. INDUSTRIAL AIR CONDITIONING quality of the product. This influence is due to the fact that the moisture content of materials having a vegetable or animal origin, and to a lesser extent minerals in certain forms, come to equilibrium with the moisture of the surrounding air. : In industries where the physical properties of a product affect its value, the percentage of moisture is of special importance. With increase in moisture content, hygroscopic materials ordinarily become softer and more pliable. Standards of regain are firmly fixed in trade with fair penalties for excesses. Deficiencies result in loss of revenue to seller'and loss of desirable quality to buyer. Manufacturing economy therefore requires that the moisture content be maintained at a percentage favorable to rapid and satisfactory manipu lation and to a minimum loss of material through breakage. A uniform condition is desirable in order that high speed machinery may be adjusted permanently for the desired production with a minimum loss from delays, wastage of raw material and defective product. In the processing of hygroscopic materials, it is usually necessary to secure a final moisture content suitable for the goods as shipped. Where the goods are sold by weight, it is proper that they contain a normal or standard moisture content. MOISTURE CONTENT AND REGAIN The terms moisture content and regain refer to the amount of moisture in hygroscopic materials. Moisture content is the more general term and refers either to free moisture (as in a sponge) or to hygroscopic moisture (which varies with atmospheric conditions). It is usually expressed as a percentage of the total weight of material. Regain is more specific and refers only to hygroscopic moisture. It is expressed as a percentage of the bone-dry weight of material. For example, if a sample of cloth weighing 100.0 grains is dried to a constant weight of 93.0 grains, the loss in weight, or 7.0 grains, represents the weight of moisture originally contained. This expressed as a percentage of the total weight (100.0 grains) gives the moisture content or 7 per cent. The regain, which is expressed as a per- centage of the bone-dry weight, is 7 0 or 7.5 per cent. The use of the term regain does not imply that the material as a whole has been completely dried out and has re-absorbed moisture. During the processing of certain textiles, for instance, complete drying during manu facturing is avoided as it might appreciably reduce the ability of the material to re-absorb moisture. A basis for calculating the regain of textiles is obtained by drying under standard conditions a sample from the lot and the dry weight thus obtained is used as a basis in the calcu lations to determine the regain. ,' The moisture content of an hygroscopic material at any time depends upon the nature of the material and upon the temperature and especially the relative humidity of the air to which it has been exposed. Not only do different materials acquire different percentages of moisture after prolonged exposure to a given atmosphere, but the rate of absorption or drying out varies with the nature of the material, its thickness and density. 599 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Regain of Hygroscopic Materials Moisture Content Expressed in Per Cent of Dry Weight of the Substance at Moisture content r.xv Humidities-Temperature. 75 F . CHAPTER 34. INDUSTRIAL AIR CONDITIONING Table 2 shows the regain or hygroscopic .moisture content of several organic and inorganic materials when in equilibrium at a dry-bulb tem perature of 75 F and various relative humidities. The effect of relative humidity on regain of hygroscopic substances is clearly indicated.' The effect of temperature is comparatively unimportant: ' In the case of cotton, for instance, an increase in temperature of 10 deg has the same effect on regain as a decrease in relative humidity of one per cent. Changes in temperature do, however, affect the rate of absorption or drying. Sudden changes in temperature cause temporary fluctuations in regain even when the relative humidity remains stationary". . . ; ; .'. The regain or moisture content affects the physical properties of textiles to a marked degree', changing the strength, pliability and elasticity. The fact that the regain of textiles will come into equilibrium with the conditions of the surrounding air and vary with its temperature and relative humidity is the fundamental basis for the control of physical qualities during manufacture. During the preparation processes in a cotton mill, the cotton fibers should be in a condition to be easily carded: These preliminary processes are carried out best in a relative humidity of 50 to 55 per cent. As the cotton fiber comes to the spinning operation, more flexibility is needed and the relative humidity is increased in. this department. For many years, 65 per cent relative humidity was con sidered the optimum. To offset the extra work performed on the fiber as the spindle speed is increased, many cotton mills now carry 70 per cent relative humidity in the spinning rooms.1 Winding, warping and weaving are all processes calling for great flexibility and a consequent need for higher humidity. Other textile fibers, due to their different natural characteristics, are processed under relative humidities and temperatures applicable to each. Rayons, on account of great loss of strength with the higher regains, should be processed in a relative humidity of 57 per cent. Acetate silk, another chemical fiber, with approximately 50 pier cent of the regain of. rayon, may be processed between 60 and 65 per cent relative humidity. All hygroscopic materials release sensible heat equivalent to the latent" heat of the moisture absorbed by the material, all of which may account for a large percentage of the total heat load. , .. CONDITIONING AND DRYING In general, the exposure of materials to desirable conditions for, treat-" ment may be coincidental with the manufacture or processing of the materials, or they may be treated separately in special enclosures. This latter treatment may be classified as conditioning or drying. The purpose of conditioning or drying is usually to establish a desired coridition of: moisture content and to regulate the physical properties of the material. When the final moisture content is lower than the initial one, the term . drying is applied. If the final moisture content is to be higher, the process' is termed conditioning. In the case of some textile products and tobacco, `The Present.Status of Textile Regain Data, by A. E. Stacey, Jr. {Notional Association of Cotton- Manufacturers. 1927). !. ' . ., 601 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 for example, drying and conditioning may be combined in one process for the dual purpose of removing undesirable moisture and accurately regu lating' the final moisture content. . Either conditioning or drying are frequently made continuous processes in which the material is conveyed through an elongated compartment by suitable means and subjected to controlled atmospheric conditions. CONTROL OF RATE OF CHEMICAL REACTIONS A typical example of the second general classification, that is, the control of the rate of chemical reactions, occurs in the manufacture of rayon. The pulp sheets are conditioned, cut to size, and passed through a mercerizing process. It is essential that during this process close con trol of both temperature and relative humidity should be maintained. Temperature controls the rate of reaction directly, while the relative humidity maintains a constant rate of evaporation from the surface of the solution and gives a solution of known strength throughout the mercerizing period. Another well-known example of this class is the drying of varnish which is an oxidizing process dependent upon temperature. High relative humidities have a retarding action on the rate of oxidization at the surface and allow the gases to escape as the chemical oxidizers cure the varnish film from the bottom. This produces a surface free from bubbles and a film homogeneous throughout. Desirable temperatures for drying varnish vary with the quality. A relative humidity of 65 per cent is beneficial for obtaining the best processing results. -, CONTROL OF RATE OF BIOCHEMICAL REACTIONS In the field of biochemical control, industrial air conditioning has been applied to many different and well-known products.- All problems involving fermentation are classed under this heading. As biochemistry is a subdivision of chemistry, subject to the same laws, the rate of reaction may be controlled by temperature. An example of this is the dough room of the modern bakery. Yeast develops best at a temperature of 80 F. A relative humidity of 65 per cent is maintained so as to hold the surface of the dough open to allow the C02 gases formed by the fermentation to pass through and produce a loaf of bread, when baked, of even, fine texture without large voids. ' Another example of a similar process is found in the curing of maca roni. The flour and water mixture is fermented and dried. As it is necessary to have a definite amount of water present to carry on a fer mentation process, the moisture must be removed in a relatively short period to stop fermentation and prevent souring and in such a manner as to avoid setting up internal strains in the mixture. Best results are obtained with the correct cycles of both, temperature and humidity. The curing of fruits, such as bananas and lemons, also come under this classification. Bananas are treated somewhat differently and to accom plish the required results, a cycle of temperatures and relative humidities is used. The starches in the pulp of the fruit must be changed and the 602 CHAPTER 34. INDUSTRIAL AIR CONDITIONING skin cured and colored, after which the fruit is cooled to maintain as slow a rate of metabolism as possible. Ideal conditions range between 55 to 57 F and in no case should the temperature go below 49 F, as the starches then become fixed and are indigestible. The curing of lemons is an entirely different problem. Bananas are cured for a quick market, while lemons are held for a future market. The process, therefore, varies in the temperature used. Temperatures from 54 to 59 F have been found to be best suited for this process. A high relative humidity of 88 to 90 per cent is necessary to hold shrinkage to a minimum and, at the same time, develop the rind so it will be sufficiently tough to permit handling. Tobacco from the field to the finished cigar, cigarette, plug or pipe tobacco, offers another interesting example of what may be done by industrial air conditioning in the control of color, texture and flavor. In the processing of tobacco, the first three classifications of air con ditioning are involved, and only through close atmospheric control can the best quality of the leaf be developed. CONTROL RATE OF CRYSTALLIZATION The rate of cooling of a saturated solution determines the size of the crystals formed. Both temperature and relative humidity are of im portance, as the one controls the rate of cooling, while the other, through evaporation, changes the density of the solution. In the coating pans for pills, gum and nuts, a heavy.sugar solution is added to the tumbling mass. As the water evaporates, each separate piece is covered with crystals of sugar. A smooth, opaque coating is only accomplished by blowing into the kettle the proper amount of air at the right temperature and relative humidity. If the cooling and drying is too slow, the coating will be rough and semi-translucent, and the ap pearance unsightly; if too fast, the. coating will chip through to the interior. Only by balancing temperature, relative humidity, and volume of air to the sugar solution, can the proper rate be obtained and a perfect coating assured. The foregoing is presented as typical of a few of the problems met with in applying air conditioning to various industrial processes. They are far from complete but with the help of a few natural laws may assist in solving others where similar basic principles are involved. CALCULATIONS The methods for determining the proper heating and cooling loads for the various industrial processes are similar to those outlined in Chapters 7 and 8. Because of the large number of motors and heat processing units usually prevalent in an industrial application, it is particularly important that operating allowances for the latent and sensible heat loads be definitely ascertained and used in the calculations to determine the total equivalent design load. HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 REFERENCES .. Effect of Air Conditioning upon Munitions, by J. I. Lyle (A.S.H.V.E. Transactions, Vol. 23, 1917, p. 383). Air Conditioning for Sausage Manufacturing Plants, by M. G. Harbula (A.S.H.V.E. Transactions, Vol. 28, 1922, p. 343). '. Air Conditioning and Refrigerating Large Bakeries, by W. L. FleisKer (Heating, Piping and Air Conditionings December, 1929, p. 621; January, 1930, p. 24). Air Conditioning for Textile Plants Making and Using Synthetic Yarns, by L. L. Lewis (Rayon Textile Monthly, July, August, September, 1930). Air Conditioning in the Bakery, by W. L. Fleisher (Heating, Piping and Air Con ditioning, February, 1931, p. 158). Air Conditioning in Industrial Processes (Match Factory), by W. L. Fleisher (Healing, Piping and Air Conditioning, March, 1931, p. 196). Air Conditioning of Press Rooms, by I. C. Baker (Heating, Piping and Air Con ditioning, July, 1931, p. 553). Pre-Cooling Fruits and Vegetables with Circulating Air, by C. E. Baker (Heating, Piping and Air Conditioning, January,1932, p. 42). ' Air Conditioning Maintains Quality of Fruits and Vegetables, by C. E. Baker (Heat ing, Piping and Air Conditioning, August, 1935, p. 369). Air Condition the Bakery Throughout, by W. W. Reece (Heating, Piping and Air Conditioning, August, 1936, p. 149). '. Air Conditioning as Applied in Theatres and Film Laboratories, by D. C. Lindsay {Transactions Society of Motion Picture Engineers, April, 1927, Vol. XI, No. 30, p. 335 365). Air Conditioning Requirements of Multicolor Offset Printing, by C. G. Weber. {Refrigerating Engineering, December, 1936, p. 6). Banana Ripening Manual, Circular No. 14, Equipment Department, Fruit Dispatch Co., New York, N. Y. The Commercial Storage of Fruits, Vegetables and Florists' Stocks, by D. H. Rose, R. C. Wright and T. M. Whiteman ( U. S. Department of Agriculture, Circular No. 278). Reactions of Lithographic Papers to Variations in Humidity and Temperature, by C. G. Weber and L. W. Snyder {U- S. Bureau Standards Journal Research, January; 1934). : Relation of Air Conditions to Tobacco Curing, by J. Johnson and W. B. Ogden (Wisconsin Agricultural Research Bureau 110: 1-48, 1931). Temperature Studies of Some Tomato Pathogens, by Alice A. Nightingale and G. W. Ramsey {V. S. Department of Agriculture -Technical Bulletin No. 520, August, 1936). The Treatment of Offset Papers for Optimum Register, by C. G. Weber and M. N. V. ..Geib ( U. S. Bureau Standards Journal Research, February, 1936). Summary Report of National Bureau of Standards- Research on Preservation of Records, by A. E. Kimberly and B., W. Scribner {U. S. Bureau of Standards Miscel laneous Publication, 154, March 16, 1937). ' 604 Chapter 35 INDUSTRIAL EXHAUST SYSTEMS Classification of Systems, Design Procedure, Requirements for Suction and Velocity, Hoods, Design of Duct Systems, Col lectors, Resistance of Systems, Efficiency of Exhaust Systems, Selection of Fans and Motors, Corrosion. IN almost every industry some type of exhaust or collecting system is essential to achieve efficient and economical control of dusts and fumes. General design information is included in this chapter which is intended to relate primarily to factory exhaust systems. CLASSIFICATION OF SYSTEMS There are two general arrangements, the central and the group systems. In the central system a single or double fan is located near the center of the shop with a piping system radiating to the various machines to be served. In the group system, which is sometimes employed where the machines to be served are widely scattered) small individual exhaust fans are located at the center of the machine groups. The group arrangement has the advantage of flexibility. Exhaust systems are also classified by the means employed to collect dust or other material handled. The dust or refuse may be collected and controlled by enclosing hoods, open hoods, inward air leakage, or by exhausting the general air of the room. . With some classes of machinery it is not feasible to closely hood the machines and in these cases open hoods over or adjacent to the machines are provided to collect as much as possible of the dust and fumes. This class includes such machines as rubber mills, package filling, machinery, sand blast, crushers, forges, pickling tanks, melting furnaces, and the unloading points of various types of conveyors. The open hoods should be placed as close to the source of dust or fumes as possible, with due regard to the movements of the operator. When,the hood must be placed at some distance above the machine it should be large enough to encompass an area of considerable extent as diffusion is usually quite rapid. Consideration must also be given to the natural movement of the fumes. For those that are lighter than air the hood should be over or above the machine and where a heavy vapor or dust-laden air at ordinary temperature is to be removed, horizontal or floor connections are required. If it is attempted to remove heavy dust such as lead oxides by an over head hood the conditions may be worse than if no exhaust were used at all, owing to. the rising air current carrying the dust up through the ;605 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 breathing zones. The objective to keep in mind in all cases is to take advantage of the natural tendency of the material to move upward or downward. . In another class of operation the main objective is to prevent the escape of dust into the surrounding atmosphere, the removal of some dust from the machine or enclosure being merely incidental. The dust-creating apparatus is enclosed within a housing which is made as tight as prac ticable, and sufficient suction is applied to the enclosure to maintain an inward air leakage, thus preventing escape of the dust. While the exhaust system is required to handle only the air which leaks in through the crevices and openings in the enclosure, yet in many installations leakages are very high and great care is required to obtain satisfactory results with a system of this kind. The inward-leakage principle is utilized for controlling dust in the operating of tumbling barrels, grinding, screening, elevating, and similar processes. Certain dust and fume producing operations are best carried on by isolating the process in a separate compartment or room and then apply ing general ventilation to this space. The compartment or room in which the work is performed should be as small as is consistent with convenience in handling the work. The ventilating system should be designed so that a strong current of clean air is drawn across the operator, and away from him toward the work, where the dust is picked up and carried from the room. . DESIGN PROCEDURE The first step in the design of an exhaust system is to determine the number and size of the hoods and their connections. No general rules, however, can be given since hood and duct dimensions are determined by the characteristics of the operations to which they are applied. When a tentative decision regarding the set-up has been made, it is then necessary to obtain the suction and air velocities required to effect control. At this point the designer must rely upon the prevailing practice and on such physical data relating to hoods, duct systems and collectors as are avail able. Finally, in choosing the fan, the area of the intake should be equal to or greater than the sum of the areas of the branch ducts. The speed, of course, must be sufficient to maintain the estimated suction and air velocities in the system. In general, the most important requirements of an efficient exhaust and collecting system are as follows1: 1. Hoods, ducts, fans and collectors should be of adequate size. 2. The air velocities should be sufficient to control and convey the materials collected. 3. The hoods and ducts should not interfere with the operation of a machine or any working part. 4. The system should do the required work with a minimum power consumption. 5. When inflammable dusts and fumes are conveyed, the piping should be provided with an automatic damper in passing through a fire-wall. 6. Ducts and all metal parts should be grounded to reduce the danger of dust ex plosions by static electricity. 7. The design of an exhaust system should afford easy access to parts for inspection and care! For more detailed requirements see Safe Practice Pamphlets Nos. 32 and 37, published by the National Safety Council, Chicago. * 606 CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS REQUIREMENTS FOR SUCTION AND VELOCITY The removal of dust or waste by means of an exhaust hood requires a movement of air at the point of origin sufficient to carry it to a col lecting system. The air velocities necessary to accomplish this depend upon the physical properties of the material to be eliminated and the Table 1. Size of Connections foe Wood-Working Machinery ' Type of Machine Diameter of Connections in - Inches Circular saws, 12-in. diam__________________________________ Circular saws, 12-24-in. diam1--.-.---------------------------------------- --------------- - Circular saws, 24-40-in. diam....------------------------------i------------------------------ Band saws, blade under 2 in. wide--------------------------------------------------------- Band saws, blade 2-3 in, wide.------- -------------- ----------------------------------------- Band saws, blade 3-4 in. wide.----------------------------------------.------ ------------ -- Band saws, blade 4-5 in. wide.---.---------------------------------- ...---------------------- Band saws, blade 5-6 in. wide_______________ Small mortisers---------------------------------------------- ---- ---------------------------------- Single end tenoners____:------------------------- .:----------------------------------------------- Double end tenoners...... .......... --:---------- ------ -...------------------- ----------- ------ Double end, double head tenoners------_...--------------------------------------------- Planers, matchers; moulders, stickers, jointers, etc.-- With knives, 6-10 in----------------------------------------------- --------- :--'--... With knives, 10-20 in______________________________ - With knives, 20-30 in--------------------------------- -------------------------------- Shapers, light work_______________________________________________ Shapers, heavy work------------.--- ------------------------------------ ---------------- ------- Belt sander, belt less than 6 in. wide._------- :------ a------------------------- ------ ... Belt sander, belt 6-10 in. wide.--------------------- ---------------- 1.-- ----- :----- Belt sander, belt 10-14 in. wide_____ -------------------------------------------- ------- Drum sander, 24 in______________________________ _______________ Drum sander, 30 ini------------------------------------------ Drum sander, 36 in_________ ,---------------------------------.--------------- .-------------- Drum sander, 48 in. . --.------------------------------------------------------------------.... Drum sander, over 48 in__________ i-------------------- ------------------------------- Disc sander, 24 in. diam------------- ------------------------------------- ;----------- i------- Disc sander, 26-36 in. diam------------ ---------------j------------------------------------- Disc sander, 36-48 in. diam------.----------- .------------------------------------------------ Arm sander.:----------------------------------------------------- ------------------------------ ------- 4 5 6 4 5 6 7 8 6 6 7 10 5-6 6- 8 6-10 4-5 ,8 5 6 7 5 6 7 ,8 10 5 6 7 4 direction and speed with which it is thrown off. If the dust to be removed is already in motion, as is the case with high-speed grinding wheels, the hood should be installed in the path of the particles so that a minimum air volume may be used effectively. It is always desirable to design and locate a hood so that the volume of air necessary to produce results is as small as possible. The static suction at the throat of a hood is frequently used in practice as a measure of the effectiveness of control. This is of considerable value where exhaust systems adapted to particular operations have been standardized by practice. Tables 1 and 2 present the duct sizes usually employed, for standard wood-working machinery and for grinding "and buffing wheels. Static pressures which in practice have been found necessary to control and convey various materials, are given in Table 3. It must be remembered, however, that the suction is merely a rough 607 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 2. Size of Connections foe Grinding and Boffino Wheels Diameter of Wheels Grinding-- 6 in. or less, not over 1 in. thick.. 7 in. to 9 in., inclusive, not over 10 in. to 16 in., " * .' 2 17 in. to 19 in., " " "3 20 in. to 24 in., " " "4 25 in. to 30 in., ""* Buffings-- 6 in, or less, not over 1 in. thick.______ 7 in. to 12 in., inclusive, not over 1% in. thick- 13 in. to 16 in., " " 2 in. "... 17 in. to 20 in., " " " 3 in. " 21 in. to 27 in., " " " 4 in. 27 in. to 33 in., " " " 5 in. measure of the air volume handled and consequently of the air velocity at the opening of the hood. The elimination of any dusty condition requires added information concerning the shape, size and location of the hood used with regard to the operation in question. In some states grinding, polishing and buffing wheels are subject to regulation by codes. The static suction requirements, which range from lYi to 5 in. water displacement in a U-tube, should be followed although in several instances they may appear to be excessive. Frequently, in these operations, a large part of the wheel must be exposed and the dust laden air within the hood is thrown outward by the centrifugal action of the wheel, thus counteracting useful inward draft. This tendency may be diminished by locating the connecting duct so as to create ah air flow of not less than 200 fpm about the lower rim of the wjieel. Exact determinations of hood control velocities are not available, but it is safe to assume that for most dusty operations they should not be less Table 3. Suction Pressures Required at Hoods Ttp* of Iusta Static Suction if Inches or - Wateb Exhausting from grinding and buffing wheels. Exhausting ifrom tuimuubulinug& b..a..i.T. elr--.--------Exhausting from wood-working machinery--light duty---------Exhausting from wood-working machinery--heavy duty......... Shoe machinery exhaust.................... ........... ...... ...........-.................. Exhausting from rubber manufacturing processes___ ^...... ........ Flint grinding exhaust.................................................. I......... ......... ... Exhausting from pottery processes.................................................. Lead dust and fume-exhaust............................................................ Fur and felt machinery exhaust___________________ ____________ Exhausting from textile machinery................................................. Exhausting from elevating and crushing machinery.--.;........... Conveying bulky and heavy materials........................................... 608 1M-5 2 2 2-4 2-3 2 2 2 2-4 2-3 2-3 2 3-5 . CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS than 200 fpm at the {joint of origin. For granite dust generated by pneumatic devices, Hatch et a1* give velocities from 150 to 200 fpm; depending on the type of hood used, as sufficient for safe control. Con sidering the character of the industry, air velocities of this order may be extended to similar dusty operations. The method for approximately determining these velocities in terms of the velocity at the hood opening is given below. . HOODS No set rule can be given regarding the shape of a hood for a particular operation, but it is well to remember that its essential function is to create an adequate velocity distribution. The fact that the zone of greatest effectiveness does not extend laterally from the edges of the opening may frequently be utilized in estimating the size of hood required. Where complete enclosure of a dusty operation is contemplated, it is desirable to leave enough free space to equal the area of the connecting duct. Hoods for grinding, polishing and buffing should fit closely, but at the same time should provide an easy means for changing the wheels. It is advisable to design these hoods with a removable hopper at the base to capture the heavy dusts and articles dropped by the operator. Such provisions are of assistance in keeping the ducts clear. Air volumes used to control many dust discharges may often be reduced by effective baffling or partial enclosure of an operation. This procedure is strongly urged where dusts are directed beyond the zone of influence of the hood. : Axial Velocity Formula for Hoods When the normal flow of air into a hood is unobstructed, the following formula may be used to determine the air velocity, at any point along the axis': y- 01 Q *'.+ 0.1 A (1) where V = velocity at point, feet per minute. \ /\ A = area of opening, square feet. x = distance along axis, feet. . . - Q = volume ol air handled, cubic feet per minute. : ..... . . . Velocity Contours It is possible by use of a specially constructed pitot-tube4 ,to map contours of equal velocity in any axial plane located in the field of in fluence. It has been found that the positions of these contours for any hood can be expressed as percentages of the velocity at the hood, opening and are purely functions of the. shape of the hood5. Control of the Silicosis Hazard in the Hard Rock Industries. I. A Laboratory Study of the Design of Dust Control Systems for Use with Pneumatic Granite Cutting Tools, by Theodore Hatch. Philip Drinker and Sarah P. Choate. (Journal of Industrial Hygiene. Vol. XII, No. 3, March. 1930). - The Control of Industrial Dust, by J. M. DallaValle (Mechanical Engineering, VoL 55, No. 10, October 1933). /" : ' `Studies in the Design of Local Exhaust Hoods, by J. M. DallaValle and Theodore Hatch; (.4.5.3/.E. Transactions, Vol. 54, 1932). .. Velocity Characteristics of Hoods under Suction, by J. M. DallaValle (A.S.H.V.E.- Transactions, Vol. 38, 1932. p. 387). .. 609 ! heating ventilating air conditioning GUIDE 1940 Further, the velocity contours are identical for similar hood shapes when the hoods are reduced to the same basis of comparison. These facts are applicable to all hood problems so that when the velocity contour distribution is known, the air flow required can be determined. Fig. 1 shows the contour distribution in two axial planes perpendicular to the sides of a rectangular hood with a side ratio of one-half. The distribu tion shown is identical for all openings with a similar side ratio provided the mapping is as shown in the figure. The contours, of course, are expressed as percentages of the velocity at the opening. UN Velocity at the Opening Air Flow from Static Readings The volume of air flow through any hood may be determined from the following equation: , Q - 4005/4 VlT (2) where . ................. Q = Volume of air flow, cubic feet per minute. 4 = area of connecting duct, square feet. . . fct, =' static suction at throat of hood, inches of water. / = orifice or restriction coefficient which varies from 0.6 to 0.9 depending on the shape of the hood. 610 CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS An average value of/is 0.71, although for a well-shaped opening a value of 0.8 may be used. The factor/is determined from the equation: ' Vt > where kv is the velocity head in the connecting duct. The term static suction is not a good measure of the effectiveness of a hood unless the area of the opening and the location of the operation with respect to the hood are known. This is clearly indicated by Equation 1 which shows that the velocity at any point along the axis varies inversely as the area of the opening and the square of the distance. However, this formula coupled with Equation 2 should serve to indicate the velocity conditions to be expected when operations are conducted external to the hood opening. Large Open Hoods . Large hoods, such as are used for electroplating and pickling tanks, should be sub-divided so the area of the connecting duct is not less than one-fifteenth of the open area of the hood. Frequently, it will be found necessary to branch the main duct in order to obtain a uniform distri bution of flow. Canopy hoods should extend 6 in. laterally from the tank for every 12-in. elevation, and wherever possible they should have side and rear aprons so as to prevent short circuiting of air from spaces not directly over the vats or tanks. In most cases, hoods of this type take advantage of the natural tendency of the vapors to rise, and air velocities may be kept low. Cross drafts from open doors or windows disturb the rise of the vapors and therefore provision must be made for them. The air velocities required also depend, upon the character of the vapors given off, cyanide fumes, for example, requiring an air velocity of approxi mately 75 fpm on the surface of the tank and acid and steam vapors requiring velocities as low as 25 to 50 fpm. The total volume of air flow necessary to obtain these velocities may be approximately determined from the following simple formula: where Q = 1.4PDV (4) Q = total volume of air handled by hood, cubic feet per minute. P -- perimeter of the tank, feet. . D -- distance between tank and hood opening, feet. V = air velocity desired along edges and surface of tank, feet per minute. Lateral Exhaust Systems The lateral exhaust method, as developed for chromium plating6, is applicable in many instances in preference to the canopy type hoods. The method makes use of drawing air and fumes laterally across the top of vats or tanks into slotted ducts at the top and extending fully along one or more sides of the tanks. The slots are 2 in. wide and for effective lUport, Vol. 43, No. 26, September 7, 1928). 611 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 ventilation a 2000 fpm exhaust air velocity at the slot face is advisable. In addition, the duct should not be required to draw the air laterally for a distance of more than 18 in. and the level of the solution should be kept 6 to 8 in. below the top of the tanks. Flexible Exhaust Systems The flexible exhaust tube method may be advantageously used for removing dust or fumes. Flexible tubes having one end connected to an exhaust system and a slotted hood attached to the other end may be shaped at will to fit in with industrial processes without affecting the ease of operation. Efficient dust or fume removal may be had with use of relatively small exhaust volumes. This type of system may be used on swing grinders, portable grinding wheels, soldering operations, stone cutting, rock drilling, etc. ' Spray Booths In the design of an efficient spray booth, it is essential to maintain an even distribution of air flow through the opening and about the object being sprayed. While in many instances spraying operations can be performed mechanically in wholly enclosed booths, the volatile vapors rrtay reach injurious or explosive concentrations. At all times the con centrations of these vapors, and particularly those containing benzol, should be kept below 100 parts per million. Spray booth vapors are dangerous to the health of the worker and care should be taken to mini mize exposure to them. ' It is recommended in the design of spray booths that the exhaust duct be located in a horizontal position slightly below the object sprayed.. Stagnant regions within the booth should be carefully avoided or should be provided with exhaust. The air volume should be sufficient to main tain a velocity of 150 to 200 fpm over the open area of the booth, and the vapors may be discharged through a suitable stack to permit dilution, but it is better practice to pass the fumes or vapors through baffle type washers or scrubbers designed for efficient spray fume removal7. Hoods for Chemical Laboratories ' Hoods used in chemical laboratories are generally provided with sliding windows which permit positive control of the fumes and vapors evolved by the apparatus. Their design should offer easy access for the installation of chemical equipment and should be well lighted. Air velocities should exceed 50 fpm when the window is opened to its maxi mum height. ' DUCT SYSTEM DESIGN The duct system should be large enough to transport the fumes or material without causing serious obstruction to the air flow. It is good practice to proportion the ducts to obtain the desired velocities and suction pressures at the hoods, although in many cases only an approxi mation to an ideal design is possible. Many exhaust hoods, and par- rpora discussion o,,f spray booths, see Special RBullllwlet;inn m0 in ift, Spprayy Painting in Pennsylvania, , Depart- of Labor and Industry, 1926, Harrisburg, Pa- 612 CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS ticularly those used in buffing and polishing, are connected by short branch pipes to the main duct which renders proportioning impractical. Construction . .. . The ducts leading from the hoods to the exhaust fan should be con structed of sheet metal not lighter than is shown in Table 4. The piping should be free from dents, fins and projections on which refuse might catch. All permanent circular joints should be lap-jointed, riveted and sol dered, and all longitudinal joints either grooved, and locked or riveted and soldered. Circular laps should be in the direction of the flow, and piping installed out-of-doors should not have the longitudinal laps at the bottom. Every change in pipe size should be made with an eccentric taper flat on the bottom, the taper to be at least 5 in. long for each inch change in diameter. All pipes passing through roofs should be equipped with collars so arranged as to prevent water leaking into the building. The main trunks and branch pipes should be as short and straight as possible, strongly supported, and with the dead ends capped to permit inspection and cleaning. All branch pipes should join the main at an Table 4. Gage of Sheet Metal to be Used for Various Duct Diameters 8 in. or less.___ 9 to 18 in_____ 19 to 25 in_____ 26 in. or more... Diamittof Duct Gaqb or Mvtal 24 22 20 18 acute angle, the junction being at the side or top and never at the bottom of the main. Branch pipes should not join the main pipes at points where the material from one branch would tend to enter the branch on the opposite side of the main. Cleanout openings having suitable covers should be placed in the main and branch pipes so that every part of the system can be easily reached in case the system clogs. Either a large cleanout door should be placed in the main suction pipe near the fan inlet, or a detachable section of pipe, held in place by lug bands, may be provided. Elbows should be made at least two gages heavier than straight pipe of the same diameter, the better to enable them to withstand the addi tional wear caused by changing the direction of flow. They should pref erably have a throat radius of at least one and one-half times the diameter of the pipe. Every pipe should be kept open and unobstructed throughout its entire length, and no fixed screen should be placed in it, although the use of a trap at the junction of the hood and branch pipe is permissible, provided it is not allowed to fill up completely. The passing of pipes through fire-walls should be avoided wherever possible, and sweep-up connections should be so arranged that foreign material cannot be easily introduced into them. 613 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Table S. Air Speeds in Ducts Necessary to Convey Various Materials Material Fine coal--------------- --------------------------- ------------------------------------------------------ Am Velocities (ppm) 2000 3000 2000 2000 2000 1500 2200 5000 4000' 4000 At the point of entrance of a branch pipe with the main duct, there should be an increase in the latter equal to their sum. Some state codes specify that the combined area be increased by 25 per cent. While this is not always necessary and is frequently done at the expense of a reduced air velocity, it is none the less advisable where future expansion of the exhaust system is contemplated. . Air Velocities in Ducts When the static suction has been fixed for a given hood, the air velocity in the duct may be determined from Equation 2. Air velocities for conveying a material should be moderate. Table 5 gives the velocities generally employed for conveying various substances. Equations 5 and 5a may be used as tests to determine the conveying efficiency of a system8. Velocities determined from these formulae should be increased by at least 25 per cent since they represent the minimum at which a stated size and density of material can be transported. For vertical ducts: V -- 13,300 --7--=- d"-B s+1 --- (5) For horizontal ducts: 6000 d. *+1 (5a) where V = air velocity in duct, feet per minute. s = specific gravity of particles. d = average diameter of largest particles conveyed, inches. Example 1. Granular material, the largest size of which is approximately 0.37 in. in diameter, with a specific gravity of 1.40 is to be conveyed in a vertical pipe the velocity of the air in which is 4100 fpm; find whether the material can be transported at this velocity. Substitute data in Equation 5a and multiply by 1.25: V = 1.25 X 13,300 X^X 0.37-" Antilog (0.57 X log 0.37) = 0.568; the required velocity is, therefore, 5500 fpm. Determining Minimum Air Velocities for Exhaust Systems, by J. M. DallaValle (A.S.H.V.E. Journal Section. Heating. Piping and Air Conditioning, September, 1932, p. 639). 614 CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS Table 6. Loss Through 90-Deg Elbows Elbow Center Line Radius in Per Cent or Pipe Diameter ' 50 100 150 200 to 300 Loss in Per Cent or Velocrt 75 26 17 14 Hence, the duct velocity must be increased either by speeding up the fan or decreasing the diameter of the duct, or both. Duct Resistance The resistance to flow in any galvanized duct riveted and soldered at the joints may be obtained from Fig. 3, Chapter 30. The pressure drop through elbows depends upon the radius of the bend. For elbows whose centerline radii vary from 50 to 300 per cent of pipe diameter, the loss may be estimated from Table 6. It is sometimes convenient to express the resistance of an elbow in terms of an equivalent length of duct of the same diameter. Thus with a throat radius equal to the pipe diameter the resistance is equivalent to a section of straight pipe approximately 10 diameters long, while with a throat diameter radius lJ^j times the dia meter, the resistance is about the same as that of seven diameters of straight pipe. COLLECTORS The most common method of separating the dust and other materials from the air is to pass the mixture through a centrifugal or cyclone collector. In this type of collector the mixture of the air and material is introduced on a tangent, near the cylindrical top of the collector, and the whirling motion sets up a centrifugal action causing the compara tively heavy materials suspended in the air to be thrown against the side of the separator, from which position they spiral down to the tail piece, while the air escapes through the stack at the center of the collector. The diameter of the cyclone should be at least 3J4 times the diameter of the fan discharge duct. When two or more separate ducts enter a cyclone, gates should be provided to prevent any back draft through a system which may not be operating. Cyclones working in conjunction with two or more fans should be designed to operate efficiently at twothirds capacity rating. The following formula is useful in computing the loss through a cyclone when the velocity of the air in the fan discharge duct is known: *< =013 (t56o)2 (6) where he = the pressure drop through the cyclone, inches of wate' r. V = the air velocity in the fan discharge duct, feet per minute. . If a cyclone is used to collect light dusts such as buffing wheel dusts, 615 ; I |^ I | HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 feathers and lint, the exhaust vent should be large enough to permit an air velocity of 200 to 500 fpm. This will, of course, require a cyclone of larger dimensions than given for the foregoing general case. When a high collection efficiency is desired, or the material is very fine, multicyclones may be used. These are merely small cyclones arranged in parallel which utilize the principle of high centrifugal velocity to attain separation. The capacities and characteristics of this type of separator should be obtained from the manufacturers. Cloth Filters _, Filters are used when the material collected by an exhaust system is valuable or cannot be separated efficiently from the air with an ordinary. cyclone. They are also employed when it is desirable to recirculate the air drawn from a room by the exhaust system, which otherwise might entail considerable loss in heat. Bag filters which are properly housed may be operated under suction. Bag houses used in the manufacture of zinc oxide and other chemical products are operated on the positive side of the fan. Wool, cotton and asbestos cloths are commonly used as filtering mediums. When woolen cloths are employed, the filtering capacities vary from }/2 to 10 cfm per square foot of filtering surface, depending on the character of the material collected. The rates for cotton and asbestos cloths are lower. The type of filter cloth and the rates of filtration depend, of course, on the material to be collected and the fan capacity.- The time increase of resistance varies with the amount of material per mitted to build up on the surface of the filter and can be determined only by experiment. The limits of the increase may be regulated by adjust ment of the shaking or cleaning mechanism. These limits may be regulated further according to the capacity of the fan and the effective performance of the hoods and the duct system. For additional information on Dust and Cinders, see Chapter 27, Air Cleaning Devices. "- . RESISTANCE OF SYSTEM The maintained resistance of the exhaust system is composed of three factors: (1) loss through the hoods, (2) collector drop, and (3) friction drop in the pipes. The loss through the hoods is usually assumed to be equal to the suction maintained at the hoods. The collector drop in inches of water is given approximately by Equation 6, but where possible' the resistance of the particular collector to be used should be ascertained from the manu facturer. Friction drop in the pipes must be computed for each section where there is a change in area or in velocity. Find the velocities in each section of pipe starting with the branch most remote from the fan. The friction drop for these sections can be determined by reference to Table 6. Total friction loss in the piping system is the friction drop in the most remote branch plus the drop in the various sections of the main, plus the drop in the discharge pipe. 616 : , CHAPTER 35. INDUSTRIAL EXHAUST SYSTEMS EFFICIENCY OF EXHAUST SYSTEMS - The efficiency of an exhaust system depends upon its effectiveness in . reducing the concentration of dusts, fumes, vapors and gases below the safe or threshold limits'. Too much emphasis cannot be placed on the necessity of testing exhaust systems frequently by determining the concentration of atmospheric con tamination at the worker's breathing level. Commonly accepted values of threshold limits for the usual gases and vapors are given in Table 7. SELECTION OF FANS AND MOTORS Manufacturers generally provide special fans for the collection of various industrial wastes. These are available for the collection of coal dust, wood shavings, wool, cotton and many other substances. For Table 7. Threshold Limits of Common Vapors and Gases3 Substance Hydrogen chloride............. Sulphur dioxide Carbon monoxide Hydrogen sulphide Methanol.. Carbon tetrachloride........ Spec. Gbat. of Gas ob Vapor (Ajb 1) 2.486 5.5 1.2678 2.2638 0.9671 1.190 2.73 1.1 5.3 INFLAMMABLE Loots (%) non-in flamm. do do do 12.5-74 4.3-46 1.4-7.0 7.5-26.5 non-inflamm. Physiological Action irritant do do do asphyxiant do anesthetic do do Maximum Allowaslb Concentration (ppm) 0.35 0.80 10.0 10.0 100.0 85-130 100.0 100.0 100.0 n5jrI^eVo)e'57ntNo. 4 ASriTurafif1 Disease8, by R' R` Sayera and h M- DallaValle {.Mechanical Enti- particular features concerning special fans, consult the Catalog Data Section of The Guide and manufacturers' data. When substances having an abrasive character are conveyed, the fan blades and housing should be protected from wear. This may be accomplished by placing a collector on the negative side of the fan or by lining the housing and blades with rubber. If no future expansion of an exhaust system is contemplated, the fan motor should be chosen to provide the calculated air volume. Should, however, the exhaust system be required to handle more air in the future, the motor should be adequate for the maximum load anticipated. Further information regarding the choice of fans and motors is given in Chapters 28 and 39. PROTECTION AGAINST CORROSION The removal of gases and fumes in many chemical plants requires that metals used in the construction of the exhaust system be resistant to l9S4Cljit<'as3;)f0r Industrial Exhaust Systems. by J- J- Bloomfield (A.S.H.V.E. Transactions, Vol. 40. 617 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 8. Materials to be Used for the Protection of Exhaust Systems Against Corrosion Ttpb of Fume Convbted Protective Material to bb Used Hydrogen sulphide----------Hydrochloric acid------------- Rubber lining or chrome-nickel alloys Aluminum coated iron, aluminum, high chrome-mckel alloys Iron or steel High chrome-nickel alloys Rubber lining, chrome-nickel alloys - Nickel-chrome alloys .Condensed from data given by Chilton and Hney (Industrial and Engineering Chemistry. Vol. 24. 1932). chemical corrosion. A list of the materials which may be used to resist the action of certain fumes is given in Table 8. Hoods and ducts when short, may frequently be constructed of wood and be. quite effective. Rubberized paints are available and may be applied as protective coatings in handling such gases and fumes as chlorine and hydrochloric acid. 618 Chapter 36 DRYING SYSTEMS Drying Methods, Driers, Mechanism, of Drying, Moisture, General Rules for Drying, Equipment, Humidity Chart, Com- bastion. Design, Estimating Methods RYING, in its broader sense, refers to the removal of water, or other D volatile liquid from either a gaseous, liquid, or solid material. In practice, the process of direct drying gaseous material is referred to generally as dehumidifying, or condensing, and in some cases chemicals are used in the adsorption or absorption of moisture. Drying a liquid is called evaporation or distillation. The common usage of the word drying refers to the removal of water or other liquid, such as a solvent, by evapo ration from a solid material. When the solid to be dried contains large amounts of free water, the actual drying process is frequently preceded by the removal of part of the water by some mechanical means, such as filtration, settling, pressing or centrifuging. Removal of as much water as possible by such methods is usually advisable, as the cost of these operations, per pound of water removed, is generally much less than by evaporation. DRYING METHODS Drying may be accomplished in any one or combination of the following methods: 1. Radiation. 2. Conduction, or direct contact. 3. Convection. Radiation The source of heat for radiation may be either the sun, or heated surfaces. Sun drying is practiced where danger from rain is slight, and where sufficient time can be allowed. Where a strict adherence to a schedule is necessary, or where dusty atmosphere is present, this method i is not in favor. Fruits are often dried in the sun. t i I1 Radiation from hot surfaces (heated by steam, electricity, or other means) furnishes generally, from one-third to one-half the total heat required for evaporation. Convection currents set up by these hot surfaces' and the cooler materials carry the balance of the heat. 619 T a b l e 1. D r ier s fo r E v a p o r a tio n of W a te r HEATING VENTILATING AIR CONDITIONING GUIDE 1940 oO'4CJ si 33 *S*S cO js e JbSO4O-* 3Ou *Oaj; Us m'O.d .2 fr E-r. gS S 3w .S-DC 3to 3 2 bo 8.-|1 to3 .2 gS Eu OC w 4) ^ 9- <4 g.* goU --~.'-cCcl rt SJ! ecd 2a oa 6i s o Vc*3c rt rt a eg3 a>.5 bo *> *E > JZ Xi y G_>, *og^ 2bCJ3 Sp ^- 5 5C *.5 Jc!} C3 *W> E 03 -4-> 4> ~ o * u jo- 4c_d> &3 5=8 4> C 3 cd t: bo 2 .E.S c0d) JZ 4-> So sit <2e *i si`o Uo ES 75S 2 -o 75*0 c l. *4i) Cg 4-> p^4 j i liil SE >.2 +D*7W<83y uoo g .2 m "1-Sf iP <0-U cd 3 28 E> o g^ CSO (9 Co W O S00 i!o S" yOO oITS .s S E2 SQ 3-2 U 2m E s .2. c9d <75 c8 .hi <w <u 8 3 |'(N cat3Dnh>(*Q*- 9 c .Ecu <D C >5 82 in a J4 Q 1CQu"= ><ua*g3 5 SS HH HHco (4 u 3u _ Q cd -gic o2 UU*=S5 'Q", > >.scd u,Qco 2CQ4J 2 -G U UcoW*uc >. -bCfi*SS cn Oc Ae> Sul 3 "O " OVO 4o> ^'" PB| f . g S2 uoiS :3iS Ucd-O<- 72a5-0crt Socub2 *Uooo- 4) 4) JJ u tn 8.6 a<>< 2. So ifr j=1.2o uos CjCa9U-) *2o3uO > a>$Uoe cl ^5.2 4r>; Ort UH O^7_ J*Uo 3 t.-S '3 4>0u <dxC>^-5_ a> 3 8 UJli CQ y *5fc .? 3 JCO ,S`S 8=5 E ax y fctd-HcJ U^ Ccdu-U3 .S-o 23 V, 8 Sii g d U a. c Oc 3 H o c< E 3 Q >> CJ oo u. C 4) 5 Ho O5o *3co 1fei I o O 620 CHAPTER 36. DRYING SYSTEMS induction or Direct Contact Drying This method of drying is advantageous where the material can be flowed on to the'drying surface and the dried material scraped off, or where the material to be dried can be handled in a sheet, and where there is no danger of subjecting the product to the full temperature of the heating medium. The source of heat for this method may be steam, electricity, hot oil or hot water. Convection The circulation of heated air or other gases about the material to be dried is generally termed convection drying. The convection may be either natural or forced.. With forced circulation, the temperature of the Am n4et cwve end etpie wen tempentm represents useful heeL Area between oven end rcem temperature represents beet in rented air Eumpfe When tk fe supplied ta oven at temperature CO IMut heat souris area Vented heat equals ana scoe e7 GH BGHJ ABJK Lb as drodated Fig. 1. Relation Between Useful and Total Heat Supplied Fig. 2. Rate of Drying of Whiting Slab drier is more uniform and the rate of drying is much higher than with natural circulation. Where humidity is used, the control is much easier, and more accurate. The source of heat for a convection drier may be steam,, electricity, hot water, oil-fired heater, gas-fired heater, or coal furnace. Where either oil, gas or coal is used, the type of heater may be direct or indirect; i.e., the products of combustion may be used (direct), or the circulated air may be heated through an interchanger (indirect). . Where the direct type is used, there is naturally a higher thermal efficiency, but it can only be used where the odor, soot, or the chemical elements of the products of combustion do not affect the material being dried. When heat economy is an important consideration this method (Fig. 1) may be used, permitting a small amount of air to be circulated, if a sacrifice of accurate control of temperature and humidity can be justified. DRIERS The term adiabatic drier is applied to a drier in which all the heat is supplied by air externally heated. The temperature of the air in the 621 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 drier decreases as a transfer of heat to the material being dried takes place. Where part or all of the heat is supplied by steam coils or other means, within the drier itself, the drier is known as a constant temperature drier. Driers using little air for heating medium with a high temperature drop,. are difficult to hold at uniform temperatures; the more air used, the easier it is to secure accurate control of temperature and humidity. Driers may be classified as shown in Table 1.' MECHANISM OF DRYING The modern theory of drying may be summed up as follows: Assuming uniform velocity and distribution of air at a constant temperature and humidity over die surface to be dried, the drying cycle will be divided into two distinct stages: 1. Constant rate period. 2. Falling rate period. The constant rate period occurs while the material being dried is still very wet, and continues as long as the water in the material comes, to the surface so rapidly that the surface remains thoroughly wet, and evapora tion proceeds at a constant rate, precisely as from a free water surface. The material assumes a temperature corresponding to the wet-bulb temperature of the surrounding air, or slightly higher, due to radiation and conduction from dry surfaces adjoining the material. The constant rate period continues until a time when the moisture no longer comes to the surface as fast as it is evaporated. This point is called the critical moisture content. As the drying proceeds, a period of uniform falling rate is entered. During this period, the surface of the material is gradually drying out, and the rate of drying falls as the remaining wet surface decreases in area. This period is also known as unsaturated surface drying. As drying continues, the surface is completely dry and the water from the interior evaporates and comes through the surface as Vapor. As the plane of water recedes, the diffusion of the vapor becomes more difficult and hence the period is known as varying falling rate period, or sub-surface drying. As drying progresses another point called equilibrium moisture content is reached, where the vapor pressure of the moisture in the air and the vapor pressure of the moisture in the material are equal, and drying ceases. The drying of a slab of whiting is shown in Fig. 2 and illustrates the principles pointed out above. The factors affecting the variations of drying rates during the above periods are pointed out in Table 2. Omissions in the Cycle Many solids, such as lumber, are so dry at the beginning of the drying operation that the constant rate period of free surface evaporation does not occur. Frequently the surface of the material is dry enough so that no surface drying can take place, in which case only the final stage of sub surface drying is involved. In other instances, the critical moisture con tent of a wet solid is sufficiently low that sub-surface drying starts almost immediately after the conclusion of the constant rate period. Thus the 622 CHAPTER 36. DRYING SYSTEMS intermediate state of unsaturated surface drying does not occur and the drying is of the sub-surface type during practically the whole of the falling rate period. With other kinds of material, particularly thin sheets, such as newsprint paper, sub-surface drying may occur at such a low moisture content that it is not encountered in commercial work, the Table 2. Factors Influencing Drying Factor Temperature Humidity Air Velocity Air direction Thickness of Material Drting Period Constant Rate, TJnsaturated Surface Sab-Surface Increase in temperature increases drying rate Increase in. temperature in creases drying rate, because with decreased viscosity, dif fusion increases Drying rate increases as humidity No effect until equilibrium con is decreased tent is reached; drying then ceases Drying rate varies approximately as the 0.6 power of the velocity No effect Drying rate increases the more nearly the air blows perpendicular to surface; for dead air film becomes thinner No effect Drying rate is not affected by the Drying rate varies inversely as thickness the square of the thickness falling rate period being confined solely in practice, to unsaturated surface drying. MOISTURE Moisture in the solid may be in either of two forms: . 1. Capillary or free. 2. Hygroscopic or chemically combined. Free moisture is contained in the capillary spaces between the particles or fibers of the materials. The loss of this moisture changes only the weight of the material. Chemically combined or hygroscopic moisture is intimately associated with the physical nature of the material and its removal changes both the physical characteristics as well as the chemical properties. The amount of hygroscopic moisture a material can contain is limited. This limit is called the fiber saturation point. When material is dried below this point, care must be exercised to avoid physical changes in the material, such as shrinkage, hardening, etc. All hygroscopic materials have definite equilibrium moisture contents dependent on temperature and humidity. Materials are frequently dried to a lower moisture content ^han those of equilibrium conditions in use, and allowed to regain the necessary moisture after leaving the drier to equalize the moisture in the material. Fig. 31 shows the equilibrium moisture content of wood. lU. S. Department of Agriculture Bulletin, No. 1136. 623 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Temperature GENERAL RULES FOR DRYING , The highest temperature possible should be used because of faster drying and smaller requirements for ventilation. The amount of moisture that can be carried by a pound of air increases rapidly with rise in tem perature as shown in. the humidity chart of Fig. 4. Too high a tempera ture may cause spoilage of materials; many materials calcine or change their chemical properties if heated too hot; gypsum and glauber salts lose some of the chemically combined water, fall apart, and change their chemical properties. Too high or rapid rise in temperatures in drying lumber or ceramics may create a liquid vapor tension within the material so high that the cells explode, causing permanent injury to the fiber. If too high a temperature is used on some chemicals, they begin to react , RELATIVE HUMIDITY IN ATMOSPHERE, PER CENT Fig. 3. Relation of Equilibrium Moisture Content in Wood to the Relative Humidity-of Surrounding Air : exothermally; a temperature rise and chemical action from within will burn the materials, e.g./bakelite products, gunpowder, etc. During the constant rate period of drying, the material heats only -to-the wet-bulb temperature of the surrounding air, consequently, high temperatures will not injure the material in this stage. ' Humidity .. Moisture in the drying air may be very important. Many materials tend to case-harden, dry on the outside, forming a skin which retards the moisture flow from the inside to the surface, or stops it completely, and so increases the drying time very much or causes a change of the physical properties of the material. It is often necessary to add humidity to the air in the initial stage of drying. Lumber case-hardens, cracks, and warps if the outside is dried too fast. Ceramics crack if not heated through before drying commences. Elastic materials warp while others crack if hot evenly dried. Many paints case-harden if not dried under high humidity. ,' ' . On the other hand, in the case of those materials whose physical or chemical properties require that they be dried at relatively lbw tem peratures high humidity tends to retard drying in the first stage and may even stop it altogether in the final stage. Where drying temperatures 624 CHAPTER 36. DRYING SYSTEMS below 120 to 140 F are used-the drying rate may be highly dependent on atmospheric humidity conditions. In such instances it is often desirable to dehumidify the air entering the drier during periods of high atmosT pheric humidity; where a high degree of uniformity is required it is often ' possible to secure complete independence of atmospheric conditions by recirculating the air in a closed system which includes a suitable dehu midifier. For this purpose absorptive dehumidifying systems have the advantage of accomplishing the desired reduction of humidity without appreciably elevating or lowering the dry-bulb temperature of the air; for this reason after-cooling is not required, and reheating is reduced to a minimum. Complete descriptions of such dehumidifying systems are given in Chapter 24 on Cooling and Dehumidification Methods. Air Circulation As noted under Mechanism of Drying, air velocity is more important in the first two stages of drying than in the last, and for this reason zone drying in continuous driers is frequently considered. It permits accurate regulation of temperature, humidity, and velocity in the different zones. High velocity results in more rapid drying, more even distribution of temperature and consequently more even drying in the first period. Too high a velocity may be detrimental because of excessive power needed for creating it, or because the material may blow away if it is light and fluffy. In the drying of paints, varnishes, and enamels, high velocity or improper distribution of the air even with the use of filters, may cause dust already in the drier, to be blown against the material, ruining the finish. Table 3 presents data on drying of various materials. EQUIPMENT FOR DRYING Equipment for drying may be divided into the following classes: 1. Heat and humidity supply. 2. Methods of handling. 3. Ovens. The heat and humidity supply for low temperature work up to 250 F is often steam; steam coils either in the oven or outside, heat the air used for drying. Circulation of heated oil, is used to a limited extent, but the danger of lealp is serious, for if the oil is hotter than the flash point, a fire may start if the oil is released to the atmosphere. In many cases where steam is not available, direct or indirect fired heaters are used with gas or oil as fuel. Indirect heaters should be carefully selected from a standpoint of long life and efficiency. The heat exchange surface should be adequate in area and easily accessible for cleaning and removal. For extremely high temperatures, alloy surface may be used. With direct-fired equip ment care must be used in the selection of burners and sufficient com bustion space allowed to insure complete combustion of fuel. Humidity can be obtained in driers by the use of steam spray, humidifiers, or recirculation. . Methods of handling of material have been indicated in Table 1. For low temperature work up to 200 F ovens and driers are commonly built of two thicknesses of insulating board (fireproof preferred), with air space between. As the temperature increases materials better able to 625 HUMID KtW rBtu PER DEG F PER DRY AIRg TEMPERATURE, DEG F F ig . 4. H u m id it y C hart HEATING VENTILATING AIR CONDITIONING GUIDE 1940 626 CHAPTER 36. DRYING SYSTEMS withstand the heat must be used. Metal lined ovens are easy to keep clean, and many high temperature driers up to 1000 F are made of metal panels with insulation between. Care should be taken to avoid through metal (metal extending through the oven from inside to out). Batch type ovens are entirely closed while in use and control of air leakage is easily taken care of. In the continuous drier where the ends are open, heat and air leakage becomes important. Warm air leaking out of the ends of ovens means a heat loss, and often the temperature and humidity outside the oven becomes unbearable. For this reason, inclined or bottom entry ovens are used, as the warm air leakage can be more easily controlled. See Figs. 5 and 6. HUMIDITY CHART FOR DRYING WORK In drying problems the chemical engineer uses different psychrometric values than those used by the heating, ventilating and air conditioning engineer. The humidity chart illustrated in Fig. 4 is based upon values determined from the following explanations: . - . . Humidity (H) is the number of pounds of water vapor carried by one pound of dry air. Percentage Humidity (%H) is the number of pounds of water vapor carried by one pound of dry air at a definite temperature, divided by the number of pounds of vapor that one pound of dry air would carry if it were completely saturated at the same temperature. Per Cent Relative Humidity (<f>) is the ratio of weight of water vapor contained in any given volume of air, to the weight of water vapor present in the same volume of saturated air, all values referring to the same temperature. . To convert from one relation to the other, where %H = 29.92 29.92 p ui p3 = vapor pressure of water, inches mercury; at dry-bulb temperature, degrees Fahrenheit. . P - *P ..................... COMBUSTION Where products of combustion are used directly in the oven, a know ledge of their formation and heat values is important. The properties of HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Table 3. Drying Time and Conditions for Representative Materials3 Material Temperature Deo F Peb Cent Relative Humidrrr Dbting . Time Apples............................................ Armatures Varnish....... ............. Banana Food Vi in. Thick.--- 140-180 200 140 6 Hrs 2.5 Hrs 4-^6 Hrs Barrels......... ................................. Beans................. ........................... Bedding.____ ... Blankets.. Brake Lining.................. Brick continuous.-........ Briquets........................... Cabbage Raw................ Candied Peel.................. Casein............................ .. 300 140 150-190 120 325 350 to 90 1100 150 165 180 15 Min 18 Hrs 40 Min 12 Min . 24 Hrs 108 Min 4.5 Hrs 2 Hrs 5 Hrs . Cereals............................. Ceramics before firing.. 110-150 150 70 to 20 24 Hrs Chicle.. Coco-fiber mats................................;........................... Cocoanut........................... ..... -...................................... Coffee.............................................................................. Conduit (Enamel)______ --..................... ..... .......... ; Cores, Oil sand for molding.---------- M--1 jn- thick 95-100 170-210 150-200 160-180 400 Max 300 10 Hrs 4-6 Hrs 24 Hrs 2 Hrs 30 Min Black sand with goulic binder/ ? j"` about 0.6 of time.....---------------|i6 In! thick 480 480 700 2.5 Hrs 4.5 Hrs . 10 Hrs Cores, Crank case (in continuous ovens)............ 525-600 2-3 Hrs Cores, Radiator (in continuous ovens)................. 275-450 1.5 Hrs Cornstalk Board......... _...... ...................................... Cotton Linters._.......................................................... 150 180 2 Hrs Enamels synthetic.... ...... ........................................... Finish coat on autos................................. ........... 225 2 Hrs + Air Dry Ice boxes all metal (white).............. Ice boxes wood inside (white)---- 290-425 225 1 Hr 3 Hrs Enamel not synthetic--..................... Fence posts green............................... Golf balls (white)............................... Small parts (auto) black.................. Steel furniture....... .............................. License plates...................................... Feathers..................................................... Films, Photographic.............................. 200 90-95 450 225-300 250 150-180 85-110 __ 40-50 1 Hr 18-36 Hrs 1 Hr 30-350 Min 1.5 Hrs :20-30 Min Fruits and Vegetables............................ 140 2-6 Hrs Furs.___________1....................................... Gelatin.......... ......... j.~.............. Glue bone, thin sheets on wire trays. Glue skin.............. ....... ............................. Glue size on furniture.--................'..... Gut............... .............................................. Gypsum board % in. thick................. Start Wet Finish 110 110 70-90 70-90 130 150 350 275 6-9 Days 2 Days 4 Hrs 60 Min Gypsum block.......................................... 350-190 8-16 Hrs Hair felt___ --.............u-- .................... Hair goods................................................ Hanks on poles........................................ Hats felt.................................................... . Hides thin leather................................ Hides heavy............................................. 180-200 150-190 120 140-180 90 70-90 1 Hr 2 Hrs 2-4 Hrs 4c-6 Days See references at end of chapter. .628 . . CHAPTER 36. DRYING SYSTEMS Table 3. Drying Time and Conditions for Representative Materials3--Con. Material Teupebatubb Deo V Per Cekt Relative Huumirr Dhtilo True Hops...... ................ ........................................................... . 120-180 Ink printing......................................................... ......,..... 70-300 Japan beds........................................................................ Japan cash register............................... ;........................ Japan metal shelving..................................................... Knitted fabrics................................................................. 300 300-450 200 140-180 1.5-2 Hrs 1.5 Hrs 30 Min Leather mulling.... ........................................................... 78-95 85 Leather thick sole......................................................... . 90 Leather uppers.............. .................................................. 80 Linoleum varnish............................................................ 110-145 70 10-30 4 Days 2-3 Days 6-10 Hrs Lithographing on tin color work...... .................... ...... 250-270 Lithographing on tin Japan........................................ ` 350 18-25 Min Lumber green hardwood..................... ......................... Lumber green soft wood................................................ Macaroni............................................................................ Matches..... ........................................................................ Matrix.............................................. ................................. Milk and other liquid foods spray dried................... Millboard sheets........ ..... :__________________ Moulds green sand C.I. flasks (one/ 8 in. thick 100-180 160-220 90-110 140-180 350 135-300 95 600 3--180 Days 2-14 Days 7.5-8 Hrs 15 Min Instantaneous 10 Hrs . 6 Hrs surface only exposed)-_____\ 13 in. thick Motors, field coils........... ............. .................................. Motors, stators:................................................................ Noodles--........................................L......... Nuts............... ...I............................................. ........................... Oil cloth............................................................................. 700 180 250 90-95 75-140 150 13 Hrs' 6 Hrs 6.5 Hrs 24 Hrs Paint, wood wheels......................................................... Paint, on sheet metal..................................................... Paper, machine dried...... .............................................. Paper, air dried............................................................... 150 350-140 180 90-200 35 8-24 Hrs 22-30 2.5 Hrs Paper wall, ground coat.................................... .......... 140 3 Min i Paper wall, varnished........ .................. ;....................... 140-160 Paper cardboard, spirit varnish................................... 150 45 15 Min 1-2 Min Peaches-............................................................................ 135 26 Hrs Pears................................................................................... 140 24 Hrs Peas.... ................................................................................ 150 6 Hrs Potatoes sliced.... ............................................................. 85 4 Hrs Potatoes steamed............................................................ Prunes.-.............................................................................. Rags............................................................................ Ramie fiber....................................................................... Rice--.................................................................................. 170 140 180 140 150 6.5 Hrs 10 Hrs Rock wool insulation...................................................... Rubber......... ...................................................................... Rubber reclaimed............................................................ Rugs................................... :.......................................... Salt...................................................................................... 300 85-90 140-200 190 350 8 Hrs 6-12 Hrs 1-2 Hrs 4-8 Hrs Rotary Drier Sand loose 1 in. deep.....................................'................. Sausage casings................................................................ Shade cloth....................................................................... Shirts--..............................................................;........ " Soap........ ............................................................................ Starch.......................... ,...................................................... Stock feed mixed.-.........;................................................ Storage battery plates.................................................... 300 110 240 120 100-125 180-200 180-220 100-110 90 for 10-15 Min 5 Hrs 1-2 Hrs 20 Min 12-72 Hrs 1-4 Hrs 20-30 Min 24 Hrs 250 Low for 6 Hrs Sugar--................................................................................ 150-200 20-30 Min 'See references at end of chapter. 629 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 3. Drying Time and Conditions for Representative Materials3--Con. ' Material Temperature DegF Pkb Cent Relative Humidmr Drying Time Tanin and other chemicals (spray dried)............._ 250-300 150-200 85-130 180-200 110 110-140 120-130 120-130 120-130 Wallboard pasted plywood------- ------ ----------- Wallboard fiber Insulating, truck type drier Wool.......... --......... ...................... ..................... -- 170 300 300-385 300-385 100 180 200 105 35 25-35 35-40 35-40 35-40 Instantaneous 12-96 Hrs 12 Hrs 12 Hrs 5-7 Hrs > Overnight 6-8 Hrs + 2 Hrs acclima tion 16-18 Hrs + 4 Hrs acclima tion 20-24 Hrs + 4 Hrs acclima tion . 15-20 Min 2H-3 Hrs 24-48 Hrs 24 Hrs 20 Min aSee references at end of chapter. the common constituents of fuel are shown in Table 4. The heating values of oils are shown in Fig. 7. The sensible heat in Btu contained in. the products of combustion of an average fuel oil and various gases is given in Fig. 8. The problem of securing complete combustion in a heater is important, in order to secure efficiency and the absence of soot formation, but unlike the ordinary power or heating boiler, excess air need not be maintained at a minimum in most cases. Excess air is generally admitted either in the heater or before the products go into the drier. ,< DESIGN In all drying problems, data regarding temperatures, time, and hu midity must be obtained by'experiment or previous experience. Experi ments are best performed at the temperatures, humidities, and velocities to be actually used in the full sized drier, and with full size samples. The following nomenclature and explanation of terms will be used iii the discussion of drying calculations: H = humidity of air, pounds of water vapor per pound of dry air. C = pounds of dry air supplied to the drier per unit of time. 5 = pounds of stock dried per unit of time in a continuous drier. S' = pounds of stock charged per batch to a discontinuous drier. 0 = time. Q = total heat supplied to the drier. 630 l CHAPTER 36. DRYING SYSTEMS = air temperature, = stock temperature. = average stock temperature over short time interval, in a batch drier, wet-bulb temperature, specific heat of the stock. = total radiation and conduction losses per unit time. pounds of water per pound of dry stock. = heat of evaporation of water. = humid heat of air, i.e., heat necessary to raise 1 lb of dry air + H lb of steam t' . <" tw s' B w r s Subscript (1) designates conditions at the point where the material in question (air or stock) enters and (2T) awbhleere4.it lGeaavseCs othmebudsriteiro. n Constants3 edth vroyAasipGneiraogsirdnaertqieweudrhissSapifcmhairmoheamnpyl3OetasetgSibhrttseeeodpslCrfkito.bvaoFLilcdtbl keIondlGfeCrBaaotoiHtshnvmunskeebtpayusoetsrmottcLiphNtobowoneentiosdtitrnucielRura0eerossqusauiisressesdlvc,yfoaoNtrLonhpsCbdopoosmesrernbebirusnasALeititnibordtinnhowpfgerCohoedCmimOcfrbfsihuleuFsttlrhueiabeeonllHPelstfrao>mdatihuricoretsi,insfNatiusrtnhsrdeet type the relation between moisture content of the stock and quantity of aCairrbroen quiredc for. 1t2h.0e00 drying o14p,1e40rat1i4o.1n40is 2g.6iv67en b8.8y73the11.e54q0ua3t.6io67n :-- 8.S73 Hydrogen Hj 2.015 187.72C3 6(J1?,1j00-- 5H1,i6)43 - S7.9(w39i --26t.o4,1)4 34.353 8.939 26.41(42) Oxygen 0, 32.000 11.819 Nitrogen IV, 28.016 13.443 Carbon Monoxide CO 28.000 13.506 4,369 4,369 0.571 Carbon Dioxide COs 44.000 S.54S 1.900 2.471 1.571 -- 1.900 Methane Ethane CHt 16.031 23.565 23.912 21.533 3.992 13.282 17.274 2.745 C,H 30.046 12.455 22.215 20,312 3.728 12.404 16.132 2.929 2.248 13.282 1.799 12.404 Propane Sulphur Dioxide C,H 44.062 8.365 21,564 19,834 3.631 12.081 15.712 2.996 1.635 12.081 sot 64.060 5.770 Water Vapor HtO 18.015 21.017 -- Air ' 28.900 13.063 All gas volumes corrected to 60 F and 30 in. mercury barometric pressure dry. 631 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 In discontinuous driers, e.g., compartment driers, the drying operation is given by the equation: ;- ' G (Hi - Hi) = S'%| (2a) In the continuous drier, the heat consumption per unit time is: = Gsi(ti - h) + G(r, + h- t',) (Hi - Hi) + S(l>, - ft) (s' + v>t) + B (3) Equation 3 assumes continuity of operation. For charge or batch operations; the total time of the drying cycle may be broken up into a number of periods, sufficiently short so that over each period average CHAPTER 36. DRYING SYSTEMS into contact with the stock with sufficient intimacy so that the air leaving the drier is saturated, or nearly so. Counter-current as against parallel flow of air and stock gives rise to optimum operating conditions, resulting in a minimum quantity of air required (G), and a corresponding minimum loss, as sensible heat, in the exit air. Similarly, continuous operation is superior to intermittent operation. . Despite the fact that the sensible heat loss increases with the rise in temperature of the air, the percentage of heat lost from this source decreases, provided the increase in moisture carrying capacity of the air, TEMPERATURE. DEG FAHR values of t, t' and H may be employed provided the third term of the right hand member of the equation is modified to read: ' . S' (t"i - P,) (s' - to,) and in the second term ' be replaced by ft + 2 ' ; Theoretically these periods should be very short and the equation integrated. Practically the error introduced by using a small number of long periods and employing average values of the variables over each, rarely introduces serious error. The evaluation of Equation 2a may be approximated in a similar manner. ................ The first term of the right hand member of Equation 3 represents heat lost as sensible heat in the effluent air. In many drying operations this becomes excessive. Each pound of air supplied should remove the maxi mum amount of.moisture. This is best accomplished by bringing the air 632 due to high temperature; is actually utilized. To secure maximum thermal efficiency in drying, a high drying temperature and high satura tion of the outlet air is imperative. Ventilation Phase The technique of attack of the ventilation phase of a drying problem is best made clear by an illustration. Assume that a material containing 40 per cent moisture is to be dried until this quantity of moisture is reduced to 5 per cent by weight. The material will stand an air tempera ture of 150 F and it is possible to provide sufficiently good contact between the material and the drying air so that the effluent air can be 633 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 brought up to 50 per cent humidity at 150 F. The drier is to use room air, the temperature and humidity of which may be assumed to average 70 F and 50 per cent, A counter-current drier will be employed and the air in this drier will be kept at a substantially constant temperature, of 150 F by heaters thermostatically controlled. The stock enters at 70 F, rises quickly to the wet-bulb temperature of the air, with which it is in Fig. 9. Temperature Humidity Relations in a Drier Vent 33J Pe n< * 422 F / Recirculation 66 per cent j rt422F-YIP_____ 15 iu product of perfect -if l combustion per pound fuel ,, -D- . Fig. 11. Excess sit tor combustion X lb at 70 F Core Drying Diagram of Combustion Products and Air contact, and is found experimentally to maintain wet-bulb temperature until the moisture content has fallen to 20 per cent. From this point its temperature rises progressively as it dries. In this range the difference in temperature between stock and air, divided by the wet-bulb depression, may be assumed proportional to the moisture content. The moisture content of the entering stock, in the units here employed, is: IOl ,, .. 40 percent water _ <,.6667: 60 per cent dry stock 634 5 per cent water = 3H 0.0527 CHAPTER 36. DRYTNC SYSTEMS tvi -- tos = A w = 0.614 lb water evaporated per pound of dry stock. Since the air leaving the drier is 50 per cent saturated at 150 F from Fig. 4, Ht -- 0.105. Similarly, Hi -- 0.008, corresponding to 50 per cent humidity at 70 F. Consequently Hi -- Hi = A H *= 0.097 lb water evaporated per pound dry air. Inspection' of Equation 2 shows that (77) is linear in w. Hence, one can construct on Fig. 9, the line marked (H) being drawn connecting the initial and final points just computed. Since the air leaving the drier has a temperature of 150 F and a humidity of 0.105, Fig. 4 shows that its wet-bulb temperature is 129 F. This is plotted at the right hand side of Fig. 9. Since the stock maintains a wet-bulb temperature down to 20 per cent moisture, where w = 0.25, the corresponding humidity can be computed by the use of Equation 2 or by reading directly from the diagram, the value being 0.0392. Fig. 4 shows that the corresponding wet-bulb temperature is 105 F. Any intermediate point on the wet-bulb temperature curve can be calculated similarly. The points for w = 0.5 are shown in Fig. 9. ' Below the point, w = 0.25, the temperature of the stock begins to rise appreciably above the wet-bulb temperature. Its temperature at any given point in this range, for example at w = 0.15, may be computed as follows: At this point, H = 0.0234 (from Equation 2) and from Fig. 4, t, = 95 F. Hence the wet-bulb depression, i -- tw = 150 -- 95 = 55 F. The assumption made regarding the relation between stock temperature and moisture content in this range may be formulated: Af w t - tw ~ 0.25 At the point w = 0.15, At' = 33 F, /' = 117 F. The temperature of the stock leaving the drier, similarly computed, is 136 F. Fig. 9 thus computed gives in graphical form the information as to the temperature humidity relationships in the drier. The air requirements can be computed by Equation 2. Thus, per 100 lb of dry stock, it is necessary to supply 633 lb of dry air. Furthermore, since from Fig. 4 it is seen that the volume of 50 per cent saturated air at 70 F, is 13.55 cu ft pier pound; 8580 cu ft of room air must be supplied per 100 lb dry stock. Similarly, since the volume of 50 per cent saturated air at 150 F is 18.0 cu ft per pound, the volume of hot wet air discharged from the drier is 11,400 cu ft per 100 lb of dry stock. Finally, the heat necessary to supply to the drier, as a whole, or to any section of it, may be computed from Equation 3. : High Temperature Drier In the design of a high temperature drier unit a method of approach to the necessary calculations involved are outlined as follows: Example 1. Cores 4 and 5 in. thick are to be dried by heating to a temperature at 400 F. An intermittent type box oven is to be used, sire 12 x 14 x 10 ft with 856 sq ft surface having an average heat transfer of 0.3 Btu per square foot per degree per hour. Drying time as determined by test is 2 hr (Fig. 10). Cores weighing 6 tons, and 15-ton steel plates, trucks etc. are delivered to the drier at 70 F. The oven is heated, by an external heater; the products of combustion and 66% per cent recirculated air will be delivered to the oven at 825 F. Fuel oil of 19,980 Btu gross and 18,830 Btu per pound net heating value, weighing 6.75 lb per gallon and having 15 lb product per pound fuel 635 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 for perfect combustion. Cores consist of 91 per cent sand, 3 per cent oil binder, and 6 per cent water. Solution. Heat required per ton of cores: Lb Material X Temp. Rise X Sp. Ht. = Btu 0.91 X 2.000 X (400 - 70) X 0,2 = 120,120 Binder.________________............... 0.03 X 2,000 X (400 - 70) X 0.4 Water heating--.......... 0.06 X 2,000 X (212 - 70) X 1.0 Water evaporation...... 0 06 X 2.000 X 970 (Fig. 4) = = .= 7,920 17,040 116,520 Water superheating (approx. 50 per cent reaches 575 F) = 0.5 X 0.06 X 2,000 X (575 - 212) X 0.45 = 9,800 Heating Load First Hour Heated to 212 F 212 F 212 F 66.7% 66.7% If X 120,120 || X 7,920 0.667 X 116,520 0.667 X 9,800 4 Btu = 51,688 = 3;408 = 17,040 = 77,680 = 6,53U 390 F 422 F Avg. 6 X 156,346 320 X 30,000 X 0.12 352 X 856 X 0.30 = 938,076 -- 1,162,000 = 90,394 2,180,470 Heating Load Second Hour 400 F 400 F 33.3% 33.3% gx 120,120 ! X 7,920 0.333 X 116,520 0.333 X 9,800 -- = 68,432 = 4,512 = 38,840 = . 3,270 ` 6 X 115,054 = 690,324 460 70 X 30,000 X 0.12 = jp2,000 575 505 X 856 X 0.30 = 129,684 Total.................................................................................................................................... 1-072-008 oBinder oxidizes and liberates heat, which is neglected in this calculation. bAverage value of coefficient is less than 0.3 because oven is not up to 575 F. This is neglected. 422 F is arrived at by taking area under curve as compared to area under 575 F ordinate. 636 CHAPTER 36. DRYING SYSTEMS Heat in 1 lb fuel oil = Heater Loss (10 per cent) = 1883 . Duct Loss (5 per cent) = 942 18,830 Btu 2,825 Btu . 16,005 Btu available to heat oven. Heat content of gases in 1 lb fueloil at 825 F is 205 Btu (Fig. 8) 15 lb X 205 = 3,075 Btu sensible heat in products of perfect combustion. 12,930 Btu to heat air X and Y , (Fig. 11). Y (Ses - Stn) 4- X (Ss - Sn) = 12930 (4) Y = 2 (X + 15) for 66.7 per cent recirculation where S = heat content of air at temperature noted taken from Fig. 8. (Recirculation and exhaust contains water vapor, products of combustion, and a greater portion of air. Heat capacities of all vary so little that they have all been assumed to be air). ' 5ms - 5c = 190 - 91 =99 5kj - Sn = 190 - 8.6 = 181.4 Substituting values of Y, H, etc. in Equation 4, (2 X- + 30) 99 4- 181.4 X = 12,930 X = 26.3 lb excess air. Y = 82.6 lb recirculating air. Total = 26.3 + 82.6 4- 15 = 123.9 lb air and products of combustion circulated per pound fuel burned. Heat in air exhausted from oven at 422 F per pound fuel burned = 0.333 X 123.9 X (5m - 5,,,) = 41.3 (91 - 8.6) = 3,400 Btu. Btu available for heating material = 16,005 -- 3,400 = 12,605 Btu per pound fuel Fuel used in first hour = 2,180,470 -5- 12,605 = 173 lb = 25.6 gal. During the second hour the heater capacity will be much greater than required. If an automatic oven temperature control operates on the oil supply, the delivery tem perature of the air entering the oven and the quantity of oil burned will decrease, the air supply being constant. Heat in air exhausted = 41.3 (Sen -- Sjo) = 41.3 (127 -- 8.6) = 4,880 Btu per pound fuel. . Heat available for heating material = 16,005 -- 4,880 =.11,125 Btu. Fuel used in second hour = 1,072,008 -s- 11,125 = 96.5 lb oil = 14.3 gal Total oil used per load = 25.6 4- 14.3 = 39.9 gal. ESTIMATING METHODS Values based on practical experience are available for rough estimating of drying problems. The temperature will drop approximately 8.5 F per grain of water evaporated per cubic foot of air (measured at 70 F) or approximately 0.62 F per pound of air at any temperature. Air will drop 55 F per cubic foot for each Btu extracted. Generally air will absorb from 2 grains to 5 grains per cubic foot of air in one passage through an air drier, depending on the temperature and the degree of contact with the material. The amount of steam required to evaporate a pound of water will vary from 1.5 lb to a more usual figure of from 2.5 to 3 lb of steam per pound of water evaporated. 637 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 REFERENCES Commercial Drying Apparatus, by L. P. Dwyer (A.S.H.V.E. Transactions, Vol. 22 1916, p. 479). ' Artificial Drying with Special Reference to the Use of Gas, by G. C. Shadwell (A.S.H. V.E. Transactions, Vol. 23, 1917, p. 231). . Drying by Evaporation, by F. R. Still (A.S.H.V.E. Transactions, Vol. 23, 1917 p. 255). ." High Temperature Drying, by Burt S. Harrison (A.S.H.V.E. Transactions, Vol. 24 1918, p. 7). . The Temperature of Evaporation, by W. H. Carrier (A.S.H.V.E. Transactions, Vol. 24, 1918, p. 25). Commercial Dehydration, by J. E. Whitley (A.S.H.V.E. Transactions, Vol. 26, 1920, p. 551). - Drying as an Air Conditioning Problem, by A. W. Lissauer (A.S.H.V.E. Trans actions, Vol. 27, 1921, p. 251). A Chronological Survey of Drying and Driers, by J. E. Bolling (A.S.H.V.E.- Journal Section, Heating, Piping and Air Conditioning, October, 1921, p. 715). Calculations tor Drying Design, by Grosvenor (Transactions, American Institute Chemical Engineering, 1908, p. 184). The Rate of Drying Solid Materials, by J. Lewis (Industrial Engineering Chemistry, 1921, p. 427). Adiabatic Drying of Hygroscopic Solids, by A. M. McCready, and W. L. McCale (Transactions, American Institute Chemical Engineers, 1933). Lignite Drier, by Lavine & Sutherland (Chemical and Metallurgical Engineering, July, 1929). Enameling Oven Economy, by B. S. Harrison (Fuels &* Furnaces, February, 1931). Powdered Yeast Prepared by Spray Drying, by A. W. Farrell (Food Industry, December, 1931). Factors that Influence Drier Performance, by A. Weisselberg (Chemical and Metallur gical Engineering, August, 1932). : Principles of Drying Lumber and Humidity Diagram, by H. D. Tiemann (Forest Service Bulletin 104, 1912). Symposium on Drying. Articles by W. K. Lewis, W. H. Carrier, A. E. Stacey and R. S. Fleming, R. G. Metz, G. B. Ridley, C. O. Lavett, D. J. Van Marie (Journal Industrial Engineering Chemistry, May, 1921). . ____ The Drying of Solids, by T. K. Sherwood (Bulletin Massachusetts Institute Technology, Nos. 237, 247 and 258). . Air Conditioning and Engineering, American Blower Co. Combustion (American Gas Association, 3rd edition, 1932). Die Trockentechnik, by M. Hirsch (Julius Springer, Berlin, 1932). . Drying (Kent's, Mechanical Engineers Handbook, 10th edition, 1923; 11th edition, 1936). Drying, by W. H. Carrier (Marks', Mechanical Engineers Handbook, 3rd edition, 1930). Drying, by Perry (Chemical Engineers Handbook, 1934). Drying by Means of Air and Steam, by E. Hausbrand (D. Van Nostrahd &Co., 1901). Drying in Industrial Plants, by J. O. Ross. Elements of Chemical Engineering, by Badger and McCabe (McGraw Hill Co., 1931). Fan Engineering, Buffalo Forge Co. ' . Fuels and Their Combustion, by Haslam and Russell (McGraw Hill Co., 1926). Heat Transmission, by W. H. McAdams (McGraw Hill Co., 1933). Modern Drying Machinery, by H. B. Grenshaw, London, 1926. Principles of Chemical Engineering, by Walker, Lewis. McAdams (Chapters on Evaporation, Humidity, and Drying, 2nd edition, McGraw Hill Co.). - The Kiln Drying of Lumber, by A. Koehler aiid R. Thelen, New York, 1926. The Kiln Drying of Lumber, by H. D. Tiemann (Lippincott, 1920). 638 Chapter 37 NATURAL VENTILATION (Find Forces, Stack Effect, Openings, Windows, Doors, Sky- lights. Roof Ventilators, Stacks, Principles of Control, General . . Rules, Measurements, Dairy Barn Ventilation, Oarage Ven- - ' tilation . ENTILATION by natural forces, supplemented in certain cases by Vwind-actuated devices finds application in industrial plants, public buildings, schools, dwellings, garages, and in farm buildings. The natural forces available for the displacement of air in buildings are, (a) wind forces, and (b) the difference in temperature between the air inside and outside the building, or a combination of the two. The results that are obtained by natural ventilating systems are variable, as they depend on wind action and temperature difference. The arrangement and control of ventilating openings should be such that the two forces act cooperatively and not in opposition. WIND FORCES In considering the use of natural wind forces for the operation of a ventilating system, account must be taken of (1) average and minimum wind velocities, (2) wind direction, (3) seasonal, daily and hourly varia tions in wind velocity and direction, and (4) local wind interference by buildings, trees, etc. Table 1, Chapter 8, gives values for the average summer wind velocities and the prevailing wind directions in various localities throughout the United States, while Table 2, Chapter 7, lists similar values for the winter. In almost all localities the summer wind velocities are lower than those in the winter, and in about two-thirds of the localities the prevailing direc tion is different during the summer and winter. While average wind velocities are seldom below 5 mph, there are many hours in each month during which the wind velocity is from 3 to 5 mph, even in localities where the seasonal average is considerably above 5 mph. There are relatively few places where the hourly wind velocity falls much below 3 mph for more than 10 daylight hours per month. Usually a natural ventilating system should be designed to operate satisfactorily with a wind velocity of 3 to 6' mph, depending on locality. 039 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 The following formula may be used for calculating the quantity of air forced through ventilation openings by the wind, or for determining the proper size of such openings: Q = EA V (1) where Q = air flow, cubic feet per minute. A = free area of inlet (or outlet) openings, square feet. V = wind velocity, feet per minute, = miles per hour X 88. E = effectiveness of openings. (E should be taken at from 50 to GO per cent if the inlet openings face the wind and from 25 to 34 per cent if the inlet openings receive the wind at an angle.} If outlet openings, where air leaves a building, are smaller than inlet openings, where air enters a building, the air will be less effective than indicated by the constant E. The accuracy of the results obtained by the use of Formula 1 depends upon the placing of the openings, as the formula assumes that ventilating openings have a.flow coefficient slightly greater than that of a square-edge orifice. If the openings are not advantageously placed with respect to the wind, the flow per unit area of the openings will be less, and if unusually well placed, the flow will be slightly more than that given by the formula. Inlets should be placed to face directly into the prevailing wind, while outlets should be placed in one of the following four places: 1. On the side of the building directly opposite the direction of the prevailing wind. 2. On the roof in the low pressure area caused by the jump of the wind (see Fig. 1). 3. In a monitor on the side opposite from the wind. ' 4. In roof ventilators or stacks exposed to the full force of the wind1. Forces Due to Stack Effect2 . The stack effect produced within a building when the outdoor tempera ture is lower is due to the difference in weight of the_warm column of air within the building and the cooler air outside. The flow due to stack effect is proportional to the square root of the draft head, or approximately: where Q = 9.4 A V H (( - to) . ' (2) : Q = air flow, cubic feet per minute. A = free area of inlets or outlets (assumed equal), square feet. . H = height from inlets to outlets, feet. f = average temperature of indoor air in height ff, degrees Fahrenheit. t0 = temperature of outdoor air, degrees Fahrenheit. . ` 9.4 = constant of proportionality, including a value of 65 per cent for effectiveness of openings. This should be reduced to 50 per cent (constant = 7.2) if conditions are not favorable. The height between inlets and outlets should be. the maximum which the building construction will allow. JAiration of Industrial Buildings, by W. C. Randall {A.S.H.V.E. Transactions, Vol. 34,1928, p. 159). Neutral Zone in Ventilation, by J. E. Emswiler (A.S.H.V.E. Transactions, Vol. 32, 1926, p. 59). Predetermining Airatton of Industrial Buildings, by W. C. Randall and E. W. Conover (A.S.H.V.E. Transactions, Vol. 37, 1931, p. 605). 640 CHAPTER 37. NATURAL VENTILATION TYPES OF OPENINGS Types of openings may be classified as: (1) windows, doors, monitor openings and skylights, (2) roof ventilators, (3) stacks connecting to registersj and (4) specially designed inlet or outlet openings. Windows, Doors and Skylights Windows have the advantage of transmitting light, as well as providing ventilating area when open. Their movable parts are arranged to open in Fig. 1. The Jump of Wind from Windward Face of Building. (A--Length of Suction Area; B--Point of Maximum Intensity of Suction: C-- Point of Maximum Pressure) various ways; they may open by sliding as in the ordinary double-hung windows, by tilting on horizontal pivots at or near the center, or by swinging on pivots at the top, bottom or side. , The proper distribution of the air in spaces to be ventilated is as im portant as that of sufficient air quantity. Advantageous pivoting of sash is very useful for securing good air distribution. Deflectors are sometimes used for the same purpose, and these devices should be considered a part of the ventilation System. Roof Ventilators The function of a roof ventilator is to provide a storm and weather proof air outlet. If it is of a type which is sensitive to wind action addi- GA 1 heating ventilating air conditioning guide 1940 Types of Stationary Ventilators Oscillating Ventilators Fig. 8 piiequiJOlS^ CHAPTER 37. NATURAL VENTILATION tional flow capacity will be produced. The capacity of a ventilator at a constant wind velocity and temperature difference, depends upon four things:. (1) its location on the roof, (2) the resistance it and the duct work offers to air flow, (3) the height of draft, and (4) the efficiency of the ventilator in utilizing the kinetic energy of the wind for inducing flow by centrifugal or ejector action. . For maximum flow induction, a ventilator should be located on that part of the roof which receives the full wind without interference. (See Fig. 1.) This does not mean that any ventilators are to be installed within the suction region created by the wind jumping over the building, or in a light court, or on a low building between two high buildings. Ventilators are highly effective in such low-pressure areas, but their ejector action, caused by wind velocity, is of little value in these locations, and hence their size should be increased proportionally. The base of the ventilator should always be provided with a taper-cone inlet in order to produce the effect of a bell-mouth nozzle (flow coefficient 0.97) rather than that of a square-entrance orifice (flow coefficient 0.60). If a grille is provided at the base of a ventilator it should be oversized as compared with the ventilator size. Air inlet openings located at lower levels in the building should be at least equal to, and preferably larger than the combined throat areas of all roof ventilators. The air discharged by a roof ventilator depends on wind velocity and temperature difference, but due to the four capacity factors already mentioned, no simple formula can be'devised for expressing venti lator capacity. Several types of roof ventilators are shown in Figs. 2 to 9. These may be classified as stationary, Figs. 2 to 4, pivoted or oscillating, Figs. 5 to 7, or rotating. Figs. 8 and 9. When selecting roof ventilators, some attention should be paid to ruggedness of construction, storm-proofing features, dampers and damper operating mechanisms, possibilities of noise from dampers or other moving parts, and possible maintenance costs. Natural ventilation units may be used to supplement power-driven supply fans, and under favorable weather conditions it may be possible to shut down the power-driven units. Where low operating costs are very important, such a combination has great advantages. Controls Gravity ventilators may have dampers controlled by (1) hand, (2) thermostatic, and (3) wind velocity, in combination with a fan. The thermostat station may be located anywhere in the building, or it may be located within the ventilator itself. The purpose of wind velocity control is to obtain a definite volume of exhaust regardless of the natural forces, the fan motor being energized when the natural exhaust capacity falls below a certain minimum, and again shut off when the wind velocity .rises to the point where this minimum volume can be supplied , by natural forces. ., Stacks Stacks or vertical flues are really chimneys and utilize both the inductive effect of the wind and the force of temperature difference (the so-called 643 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 gravity action). Like the roof ventilator, the stack outlet should be located, so that the wind may act upon it from any direction. With little or no wind, chimney effect depending on temperature differ ence and lower outdoor temperature will produce a removal of air from the rooms where the inlet openings are located. HEAT REMOVAL In problems of heat removal, knowing the amount of heat to be removed and having selected a desirable temperature difference, the amount of air to be passed through the building per minute to maintain this temperature difference can be determined by means of the following equation : VH Q = c 60 (I - to) (3) where c = 0.24 = specific heat of air. V = specific volume of the air, cubic feet per pound, about 13.5. (See Chapter 1.) H = heat to be carried off, in Btu per hour. Q = air flow in cubic feet per minute. 1 = inside temperature, degrees Fahrenheit. to = outside temperature, degrees Fahrenheit. , For disposing of odors or other air impurities, the amount of outside air to be introduced must be of such quantity to dilute the impurities to a degree that they are no longer objectionable. See Chapter 3 for the minimum of outside air necessary for ventilation. For garage ventilation, sufficient air must be admitted to dilute the carbon monoxide content of the-indoor air to 1 in 10,000 (see Garage Ventilation in this Chapter). Suggested methods for estimating the air flow due to temperature difference alone and to wind alone have already been given. It must be remembered that when both forces are acting together, even without interference, the resulting air flow is not equal to the sum of the two estimated quantities. The same openings have been assumed in both cases, and since the resistance to flow through the openings varies ap proximately with the square of the velocity*, this resistance becomes a limiting factor as the flow through the openings is increased. Recent investigations*4 show that the total flow is only 10 per cent above.the flow caused by the greater force when the two forces are nearly equal, and this percentage decreases rapidly as one force increases above the other. Tests on roof ventilators indicate that this is too conservative in the direction of low total flow quantities, but there is in any case a large judgment factor involved. The wind velocity and direction, the outdoor temperature, or the indoor activities cannot be predicted with certainty, and great refinement in calculations is therefore not justified. When designing for winter conditions, an added variable is the heat lost by direct flow through walls and windows and by infiltration. . *Loc. 4This iCs ittr.uNeofoterstu1rbaunlden2t. flow only. It would be more correct to state that the resistance varies approxi mately with V} for high to moderate velocities, with V1-* for moderate to low velocities, and with the first power of the velocity for very low velocities through small openings. 644 CHAPTER 37. NATURAL VENTILATION Example 1. Assume a drop forge shop, 200 ft long, 100 ft wide, and 30 ft high. The cubical content is 600,000 cu ft, and the height of the air outlet over that of the inlet is 30 ft. Oil fuel of 18,000 Btu per lb is used in this shop at the rate of 15 gal per hour (7.75 lb per gal). Temperature differences are 10 F in summer and 30 F in winter, and the wind velocity is 5 mph in summer and 8 mph in winter. What is the necessary area for the inlets and outlets, and what is the rate of air flow through the building? Solution. The system must be designed for the summer conditions as these are the more severe. The heat to be removed per hour is: H = 15 X 7.75 X 18,000 = 2,092,500 Btu. By Equation 3, the air flow required to remove this heat with a temperature difference of 10 deg is: n0 - c 60 (Vt H- to) _ 103..254 XX 26,009X2,51000 _ 11906R,117_2,, c,fm0.24 X 60 X 10 This is equal to 19.6 air changes per hour. The assumption is made that the average temperature difference between indoors and outdoors is the same as the temperature rise of the air from the inlet opening to the outlet opening. Actually, the latter difference is larger and 60 the value of 19.6 air changes per hour is conservative as it allows for more cooling than is necessary for an overage temperature difference of 10 deg. If 196,172 cfm are to be circulated by theforce of the temperature difference alone, the area of opening would be, by Equation 2: ,Q 196,172 " 9.4 V H(t - to) ~ 9.4 V 30 X 10 ,_ c ' . If this area of openings were provided, a wind velocity of 5 mph, acting alone, would produce a flow according to Equation 1, of: Q =. EA V = 0.50 X 1,205 X 5 X 88 = 265,100 cfm. If the inlet openings do not face the wind, but are at an angle with it, about half this amount may be considered to flow. , A factor of judgment must now be exercised in making the selection of the area of openings to be specified. Apparently 1205 sq ft are a very generous allowance because either a direct wind of 5 mph or an average temperature difference of 10 deg acting alone will more than suffice to carry away the heat, and when the two forces are acting together, the system may have an excess capacity of 25 per cent to 50 per cent, especially if the outlets are made up partially of roof ventilators which employ the force of the wind for producing a suction effect. On the other hand, the wind may at times come from an unfavorable direction/ or its velocity may fall below 5 mph or the building construction may not permit a full 2400 sq ft of inlet window area and an equal amount of monitor or roof ventilator outlet area. In case the two sets of openings are not equal, their effectiveness is reduced. . From this example, it must be apparent that while formulas may furnish a reliable guide, the final solution of a problem of natural venti lation requires a common sense analysis of local conditions to supplement and to modify the dictates of the formulas. GENERAL RULES A few of the important requirements in addition to those already outlined are: . 1. Inlet openings in the building should be well distributed, and should be located on the windward side near the bottom, while outlet openings are located on the leeward side near the top. Outside air will then be supplied to the zone to be ventilated. 645 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 2. Direct short circuits between openings on two sides at a high level may clear the air at that level without producing any appreciable ventilation at the level of occupancy. 3. Roof ventilators should be located 20 to 40 ft apart each way and preferably on the ridge of the roof. The closer spacings are used when ventilating rooms with low ceilings. 4. Greatest flow per square foot of total opening is obtained by using inlet and outlet openings of nearly equal areas. 5. In an industrial building where furnaces, that give off heat and fumes, are to be installed, it is better to locate them in the end of the building exposed to the prevailing wind. The strong suction effect of the wind at the roof near the windward end will then cooperate with temperature difference, to provide for the most active and satisfactory removal of the heat and gas laden air. , 6. In case it is impossible to locate furnaces in the windward end, that part of the building in which they are to be located should be built higher than the rest, so that the wind, in flashing therefrom will create a suction. The additional height also increases the effect of temperature difference to cooperate with the wind. - 7. In the use of monitors, windows on the windward side should usually be kept closed, since, if they are open, the inflow tendency of the wind counteracts the outflow tendency of temperature difference. Openings on the leeward side of the monitor result in cooperation of wind and temperature difference. 8. In order that the force of temperature difference may operate to maximum advan tage, the vertical distance between inlet and outlet openings should be as great as possible. Openings in the vicinity of the neutral zone are less effective for ventilation. 9. In order that temperature difference may produce a motive force, there must be vertical distance between openings. That is, if there are a number of openings available in a building, but all are at the same level, there will be no motive head produced by temperature difference, no matter how great that difference might be. 10. In the design of window ventilated buildings, where the direction of the wind is quite constant and dependable, the orientation of the building together with amount and grouping of ventilation openings can be readily arranged to take full advantage of the force of the wind. On the other hand, where the direction of the wind is quite variable, it may be stated as a general principle that windows should be arranged in sidewalls and monitors so that there will be approximately equal area on all sides. Thus, no matter what the wind's direction, there will always be some openings directly exposed to the pressure force of the wind, and others opposed to a suction force, and effective movement through the building will be assured. ' 11. The intensity of suction or the vacuum produced by the jump of the wind is greatest just back of the building face. The area.of suction does not vary with the wind velocity, but the flow due to suction is directly proportional to wind velocity. . 12. Openings much larger than the calculated areas are sometimes desirable, especially when changes in occupancy are possible, or to provide for extremely hot days. In the former case, free openings should be located at the level of occupancy for psychological reasons. 13. Special consideration should be given to the possibility of sidewall or monitor windows being closed on account of weather conditions. Such possibilities favor roof ventilators and specially designed stormproof inlets. MEASUREMENT OF NATURAL AIR FLOW The determination of the performance of any ventilating system involves measurements which are not easy to make. The difficulties are increased in the case of natural ventilation, since the motive forces and the air velocities are very small. The measurements necessary for giving the capacity of a system are (1) velocity of the wind, (2) velocity of the air through inlet and outlet openings, (3) outdoor air temperature, and (4) average indoor air temperature. (See Chapter 45.) 646 CHAPTER 37. NATURAL VENTILATION DAIRY BARN VENTILATION 6 A successful barn ventilating system is one which continuously supplies the proper amount of air required by the stock, with proper distribution and without drafts, and one which removes the excessive heat, moisture, and odors, and maintains the air at a proper temperature, relative humidity, and degree of cleanliness. Barn temperatures below freezing and above 80 F affect milk produc tion. . Milk producing stock should be kept in a bam temperature be tween 45 and 50 F. Dry stock, at reduced feeding, may be kept in a barn 5 to 10 deg higher. Calf barns are generally kept at 60 F, while hospital and maternity barns usually have a temperature of 60 F or somewhat higher. The heat produced by a cow of an average weight of 1000 lb may be taken as 3000 Btu per hour. The average rate of moisture production by a cow giving 20 lb of milk per day is 15 lb of water per day, or 4375 grains per hour. To set a standard of permissible relative humidity for cow. barns is difficult. For 45 F an average relative humidity of 80 per cent is satisfactory, with 85 per cent as a limit. Where the barn volume is within the limit that can be heated by the stabled animals, the air supply need not be heated. The air should be supplied through or near the ceiling. It is better to have the exhaust openings near the floor as larger volumes of warm air are then held in the barn and there is better temperature control with less likelihood of sudden change in barn temperature. If a cow weighs 1000 lb and produces 3000 Btu of heat per hour, and if a bam for the cow has 600 cu ft of air space with 130 sq ft of building exposure, one cow will require 2600 to 3550 cfh of ventilation, depending on the temperature zone in which the barn is located. The permissible heat losses through the structure, based on one cow and depending on the temperature zone, vary between 0.043 and 0.066 Btu per hour per cubic foot of barn space, and 0.197 to 0.305 Btu per hour per square foot of bam exposure. CARAGE VENTILATION On account of the hazards resulting from carbon monoxide and other physiologically harmful or combustible gases or vapors in garages, the importance of proper ventilation of these buildings cannot be over emphasized. During the warm months of the year, garages are usually ventilated adequately because the doors and windows are kept open. As cold weather sets in, more and more of the ventilation openings are closed < and consequently on extremely, cold days the carbon monoxide concentra tion runs high. Many garages can be satisfactorily ventilated by natural means par ticularly during the mild weather when doors and windows can be kept `Dairy Barn Ventilation, by F. L. Fairbanks (A.S.H.V.E. Transactions, Vol. 34, 1928, p. 181). Cow Barn Ventilation, by Alfred J. Offner (A.S.H.V.E. Transactions, Vol. 39, 1933; p. 149). For additional information on this subject refer to Technical Bulletin, U. S. Department of Agriculture (1930), by M. A. R. Kelley. 647 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 open. However, the A.S.H.V.E. Code for Heating and Ventilating Garages, adopted in 1929 and revised in 1935, states that natural venti lation may be employed for the ventilation of storage sections where it is practical to maintain open windows or other openings at all times. The code specifies that such openings shall be distributed as uniformly as pos sible in at least two outside walls, and that the total area of such openings shall be equivalent to at least 5 per cent of the floor area. The code further states that where it is impractical to operate such a system of natural ventilation, a mechanical system shall be used which shall provide for either the supply of 1 cu ft of air per minute from out-of-doors for each square foot of floor area, or for removing the same amount and discharging it to the outside as a means of flushing the garage.6 Research ' Research on garage ventilation undertaken by the A.S.H.V.E. Com mittee on Research at Washington University, St. Louis, Mo., and at the University of Kansas, Lawrence, Kans., in cooperation with the A.S.H. V.E. Research Laboratory, and at the A.S.H.V.E. Research Laboratory has resulted in authoritative papers on the subject. Some of the conclusions from work at the Laboratory are listed in the following statements: 1. Upward ventilation results in a lower concentration of carbon monoxide at the breathing line and a lower temperature above the breathing line than does downward ventilation, for the same rate of carbon monoxide production, air change and the same temperature at the 30-in. level. 2. A lower rate of air change and a smaller heating load are required with upward than with downwardJventilation. 3. fn the average case upward ventilation results in a lower concentration of carbon monoxide in the occupied portion of a garage than is had with complete mixing of the exhaust gases and the air supplied. However, the variations in concentration from point to point, together with the possible failure of the advantages of upward.ventilation to accrue, suggest the basing of garage ventilation on completejnijdng and an air change sufficient to dilute the exhaust gases to the allowable concentration of carbon monoxide. 4. The rate of carbon monoxide production by an idling car is shown to vary from 25 to 50 cfh, with an average fate of 35 cfh. 5. An air change of 350,000 cfh per idling car is required to keep the carbon monoxide concentration down to one part in 10,000 parts of air. Code for Heating and Ventilating Garages (A.S.H.V.E. Transactions, Vol. 35, 1929, p. 355), (A.S. H.V.E. Reprint, January, 1935). Airation Study of Garages by W. C. Randall and L. W. Leonhard (A.S.H.V.E. Transactions, Vol. 36, 1930. D. 233). A.S.H.V.E. Research Report No. 874---Carbon Monoxide Concentration in Garages, by A.S. Langs* dorf and R. R. Tucker (A.S.H.V.E. Transactions, Vol. 30, 1930, p. 511). A-S.H.V.E. Research Report No. 935--Carbon Monoxide Distribution in Relation to the Ventilation of an Underground Ramp Garage, by F. C. Hougbten and Paul McDermott (A.S.H.V.E. Transactions, Vol. 38, 1932. p. 439). . ` , A.S.H.V.E. Research Report No. 934--Carbon Monoxide Distribution in Relation to the Ventilation of a One-Floor Garage, by F. C- Houghten and Paul McDermott (A.S.H.V.E. Transactions. Vol. 38,1932, p. 424). A.S.H.V.E. Research Report No. 967--Carbon Monoxide Distribution in Relation to the Heating and Ventilation of a One-Floor Garage, by F. C.' Houghten and Paul McDermott (A.S.H.V.E. Trans actions, Vol. 39, 1933, p. 395). ., Carbon Monoxide Surveys of Two Garages, by A. H. Sluss, E. K. Campbell and, Louis M. Farber (A.S.H.V.E. Transactions. Vol. 40. 1934, p. 263). 648 Chapter 38 AUTOMATIC CONTROL Purpose of Automatic Control, Definitions of Control Units and Terms, Types of Control, Central Fan Systems, Unit Systems, Control of Automatic Fuel Appliances, Residential Control Systems, Control of Refrigeration Equipment, Indus- trial Processes HIS chapter is prepared with the purpose of acquainting the engi Tneer with the principles underlying the use of automatic control, the general types and varieties of control equipment available and their application. Automatic control, properly applied to heating, ventilating and air conditioning systems, makes possible the maintenance of desired con ditions with maximum operating economy. A properly designed and complete control system has the ability to interlock and coordinate the various functions of heating, ventilating and air conditioning in a manner impossible to accomplish with manual regulation. Automatic control is an integral and essential part of a heating, venti lating or air conditioning installation and cannot be regarded as an acces sory. In order to insure satisfactory results, the control should be designed with and incorporated in the heating, ventilating or air conditioning system. The control equipment should be given careful consideration in the planning of any installation in order that the entire system may operate together with satisfactory results. ,. In order that proper selection and application of controlling devices may be made it is important that a broad understanding' exist as to the types of control available and their principles of operation. Improper selection and application of control equipment will result in unsatis factory and inefficient operation. Specific control devices and systems are described in the Catalog Data Section. ' PURPOSE OF AUTOMATIC CONTROL Automatic control is normally applied to heating, ventilating or air conditioning systems: 1. To insure the maintenance of certain desired or required conditions of temperature, pressure, humidity, air motion or air distribution. 2. To serve a safety function, limiting pressures or temperatures within predetermined points, or preventing the operation of mechanical equipment unless it may function without hazard. 3. To produce economical results and thereby insure operation of the system at a minimum' of expense. . 649 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 DEFINITIONS OF CONTROL UNITS AND TERMS Controlling devices and terms commonly used in the automatic control of heating, ventilating and air conditioning systems are: Thermostats: Thermostats are defined as temperature sensitive devices reacting to temperature changes. There are four major types of thermostats. A Room. Thermostat is normally installed on the wall of the room whose temperature it is to control, and in reacting to rising or falling tem peratures, the thermostat causes the operation of heating or cooling equipment so that desired temperatures will be maintained. , The temperature sensitive element will usually consist of a bi-metal strip or coil, or a vapor-filled bellows as illustrated in Fig. 1. Bi-Metallic straight strip type Fig. 1. Typical Thermostatic Elements Immersion Thermostats are used for controlling liquid temperatures. The sensitive element will normally be encased in a protective well which is inserted in the liquid, the temperature of which is being controlled. ' The temperature sensitive element will usually consist of a bi-metal coil, thermal expansion rod, or a vapor-filled system. If the latter is used the temperature sensitive bulb may be connected to the case of the instrument by either a flexible or rigid tube. Insertion Thermostats are similar to immersion thermostats except that they are for use in controlling the temperature of a gas such as air. The sensitive element will often be encased in a protective well which prevents mechanical damage but which permits the gas to come in direct contact witShurtfhaeceeleTmheernmt.ostats include those devices which measure surface temperatures. These surface temperatures will often be an indirect measure of the temperature of a gas or fluid as in the case of a pipe within which water is flowing. The sensitive element will usually be placed in direct contact with the surface of the object whose temperature it is to measure and may consist of a bi-metal spiral or vapor-filled bellows. 650 CHAPTER 38. AUTOMATIC CONTROL Humidity Controls: Humidity controls are defined as automatic * devices reacting to changes in relative humidity. Within this group, the devices which operate in controlling humidity supplying equipment are regulating devices and when operating only to prevent relative humidity from exceeding a predetermined maximum are a form of limit control. The humidity sensitive element may consist of hair, paper, wood, skin or. any other material which changes its dimensions with changes in humidity. Controls are available provided with both temperature and humidity sensitive elements, which operate to maintain definite relations between dry-bulb temperature and relative humidity. Pressure Controllers: Pressure controllers are defined as devices reacting to pressure and pressure changes. Examples of such devices are the pressure controls governing the operation of refrigeration equipment from either head or suction pressure, devices reacting to steam or water pressure or the pressure of air in the distribution systems. Damper Motors: Damper motors are defined as specialized power units, the purpose of which is to position outdoor air, face, by-pass or distribution dampers, regulating the flow of air through the system. Connected by suitable linkages, these damper motors react at the com mand of thermostats, humidity controllers and pressure controllers to adjust the air flow to the needs of the system. Control Valves: Control valves are defined as steam valves, water valves or air valves which may be adjusted at the command of con trollers to regulate the flow of the medium.passing through them to the needs of the system. Such control valves are usually constructed with an electric or pneumatic power unit connected to the valve stem so that the movement of the power unit will react to position the valve as con ditions demand. Self-contained valves are also included under this classification. Their application is principally limited to the regulation of the steam supply to individual radiators in two-pipe low pressure steam heating systems, and the temperature of hot water supply tanks. Solenoid Valves: Solenoid valves are, as their name implies, valves actuated by the magnetic effect of an electric solenoid built within them. While normally these valves are opened when the solenoid is energized, they are sometimes built in a reverse acting manner and closed when energized. In heating, ventilating and air conditioning systems, they are normally adapted to the control of oil or gas burners as fuel valves, as Water valves on humidifiers, or as refrigerant valves in refrigeration systems. Relays: A relay is defined as a unit installed between a controller and the device under control, for purposes of amplifying the capacity of the controller or performing an auxiliary control function. For example, a thermostat, in order to preserve its sensitivity may be constructed so that it is not capable of handling the power required of a motor. A relay is, therefore, installed between the two. The thermostat actuates the relay and the relay, in turn, actuates the motor. Motor-driven switching devices are also often used as relays. 651 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 TYPES OF AUTOMATIC CONTROL Operating Media or Source of Power Supply Automatic control systems may be classified in three broad groups based upon their primary operating media or source of power, as follows: 1. Electric Control Systems. In such control systems the primary medium utilized to provide for the operation is electricity, and the basic function of these controls consists of switching or otherwise adjusting electric circuits to govern electric motors, relays or solenoids. The individual units of this type of system are interconnected by line voltage or low voltage wiring, and this wiring serves to complete the circuits carrying the commands of the controllers to the controlled valves or damper motors. 2. Pneumatic Control Systems. In the pneumatic control systems, the primary source of operation is obtained through a medium of compressed air, the pressure of which is varied by the controlling devices. In these systems one or more centrally located air compressors furnish a supply of compressed air which is distributed in special piping to the various con trolling and controlled devices. By means of leak ports or orifices, the pressure of the air is varied in the branch lines and the changing pressures are utilized in air operated damper motors or valves to obtain the move ment necessary to the operation of valves and dampers. 3. Self-Contained Control Systems. In self-contained control systems, the primary source of operation is the vapor pressure of a volatile liquid in the closed thermal system of the controller, which is increased or decreased in direct proportion to variation of the temperature in the controlled medium. These pressure changes are transmitted directly to the control valve or damper motor. Applications consist of valves or dampers to regulate the flow of heating or cooling media to coils, radiators, or liquid tanks, as determined by the controller element. . Motion of Controlled Equipment ____ Automatic control equipment can also be classified into two general types with respect to the characteristics of the motion imparted by the controls to the controlled equipment, such as two position or positive acting control and modulating or graduated-action control. . In any control system it is necessary to choose the type of equipment whose characteristics permit the type of control operation desired and in many cases both types of control are used in the same system to best meet various requirements. 1. Two Position or Positive-acting Control. This type of control operates positively between two positions such as on and off or open and closed with no intermediate positions or degrees of motion between the two extremes of operation. A simple thermostat which starts and stops an oil burner or a unit heater motor is an example of this type. As applied to a valve or a damper, the action of the controlling device would serve to fully open or fully close the valve or damper. ' In some applications of this type of control, artificial heat is applied to the sensitive element of the room thermostat at the same time that heat is being added to the space under the control of the thermostat in order to 652 CHAPTER 38. AUTOMATIC CONTROL increase its sensitivity. This usually results in more accurate control and more frequent operation of the heat source. 2.Modulating or Graduated-acting Control. This type of control causes motion in the controlled device in proportion to motion caused in the controller by fractional degree variations in the medium to which the controller is responsive. After a fractional change has been measured at the controller and has effected a new position of the valve or damper in proportion to the amount of such change, the system stands by awaiting further change at the controller before any additional motion occurs. The extent of the motion is limited only by the limits of the controller and by the intensity of the change of conditions as measured. With this type of control, the damper or control valve may be operated in intermediate positions between its extreme limits in order to properly modulate or proportion the flow of air, steam or water, reacting with changes of con ditions at the controller. Various modifications of this type of control are available, designed to meet special requirements and conditions, all based on operation of the controlled equipment in intermediate positions. This type of control motion cannot be used on valves of one-pipe steam systems as the partial opening of the valves will not permit the condensate to escape against the flow of incoming steam. Where this type of control is used to control the flow of steam to a heater coil of a fan system which is in the direct path of untempered outdoor air at temperatures below freezing, care should be taken that the control point and operating char acteristics of the regulator are such that the valve is fully open at temper atures below freezing, to avoid the possibility of freezing condensate in the bottom of the coil; Division of Space Under Control Control systems vary considerably with the type and size of the building, occupancy of the building, and with the heating or cooling system, humidity supplying equipment and ventilating means available for control. In the following paragraphs the general requirements of various phases of these different buildings will be discussed. 1. Individual Room Control. The most accurate and flexible form of control for any structure is that calling for the regulation of each indi vidual room by control equipment reacting to conditions in that room only. Such control necessitates a thermostat in each room, located to properly measure the conditions of the room, controlling the radiator, unit heater, unit ventilator or other heating source supplying heat to that room only in which the thermostat is located. This arrangement permits the maintenance of any desired conditions in any room, entirely inde pendent of any other room. In the case of large rooms, where one ther mostat location will not serve to properly measure the conditions through out the room, and where two or more sources of heat supply are provided in the room, additional thermostats may be used, each controlling its respective section of the heating source. This form of control, due primarily to the number of control, devices required over the entire building, normally is the most expensive type of control system. How ever, where maximum flexibility and the most accurate control is desired, individual room control can be depended on to furnish the desired results. 2. Single Thermostat Control. Probably more widely used than any 653 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 other form of control is the type of automatic system regulated entirely from a single room thermostat. The wide use of this particular means of control is primarily due to the fact that it is the form of regulation best adapted to residences and small buildings, which far out-number the larger structures. In larger buildings, this form of control has definite short comings. In the small buildings and average size residences it is possible to select a location and install a thermostat of suitable characteristics which, in controlling from the surrounding air temperature, will hold the temperature of the entire building within entirely satisfactory limits; It must be recognized that the thermostat reacts to and controls from the temperatures to which it is subjected and that, therefore, the position ' selected for the thermostat must be representative of general conditions throughout the structure. It must further be recognized that if certain areas or rooms of a structure are not properly balanced as regards heating or cooling capacity and distribution, the control as dictated by the ther mostat will not produce satisfactory results in these unbalanced areas. 3. Zone Control. As the size of buildings increases, it becomes in creasingly difficult to provide proper regulation for the entire structure from a single thermostat control. In such instances, where the advantages of individual room control are not obtainable by reason of its cost, an intermediate form of control system is available, commonly described as zone control. In this form of control system a building is divided into areas or zones such that the general requirements and the general con ditions through the areas are relatively constant as to exposure and occupancy, and then each zone is provided with control equipment which functions to regulate the conditions in that particular zone. As in the case of individual room control, each zone may be regulated to its own needs which may vary from the needs of other zones within the same structure. Variations of the usual zone control methods by the use of recently developed special devices have been quite successful in obtaining greater economy from heating systems. Frequently these use an outside ther mostat or group of thermostats which adjust the operation of the controls to conform to variations in weather conditions. CENTRAL FAN SYSTEMS A central fan system includes any conditioning system by which either outdoor air, return air, or combinations of outdoor and return air, are conditioned at a central point and then distributed through duct work to the various sections of the space being conditioned. Heating Cycle Central fan ventilating systems may be sub-divided, first into split systems, by which air is supplied for ventilating purposes only and heat is supplied in winter from another source such as direct radiationand second, into combined systems, in which the functions of ventilation and heating are both performed by the central fan system. A control system for a central fan ventilating system using all outdoor air and discharging air at a predetermined temperature is illustrated in Fig. 2. Thermostat Ti located in the outdoor air intake is set just above 654 CHAPTER 38. AUTOMATIC CONTROL . freezing, and controls valve Vt on the first heating coil. This valve must * be "completely open or completely closed to avoid danger of freezing. The by-pass damper around the heaters and the other two valves Vt and Vs are controlled by thermostat T2 located in the discharge duct from the fan. If the temperature of the discharge air increases, through the action of Tt the damper is moved automatically to admit more cold air. Should this not reduce the temperature sufficiently, the valves V2 and Vs on the heating coils will be closed gradually and in sequence until the correct temperature is reached. The control of the damper and valves Vs and V3 must be gradual or there will be a wide fluctuation in temperature. In ventilating systems it is customary to supply air to the ventilated spaces at an inlet temperature approximately equal to the temperature maintained in the rooms. The radiators therefore are designed to take care of all the heat losses from the room and in order to maintain con trolled room temperatures it is necessary to control the radiators in dependently of the ventilation control. . Fig. 2. Control of a Central System for Ventilation In some installations, such as theatres and auditoriums, it is difficult to install sufficient direct heating surface to offset the heat losses from the room. There are also installations where a short heating-up period is allowed before occupancy of the room, and in these cases it is necessary to use the entire heating capacity of the ventilating system for this purpose. An additional thermostat may be installed in the room which will take the control away from the fan discharge thermostat (Tt in Fig, 2) and utilize the full heating capacity when the room is below normal temperature. . In central fan systems, air washers are often used and in such cases, due to the effect of temperatures on' humidity, additional control is required. Ah arrangement with control of the second tempering heating coil from the air washer temperature and with the usual control of the first tempering heating coil from the outside temperature is shown in Fig. 3. This permits the air to be kept cool while passing through the washer so that too much moisture will not be absorbed. Control of . the reheating units and by-pass damper by an insertion thermostat in the fan discharge, and the application of a pilot thermostat to a system of this sort is illustrated in Fig. 3. ;. 655 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Where a number of rooms are to be heated and ventilated through one central fan system it is customary to provide tempering heating units, automatically controlled to provide a minimum temperature for venti lation only and additional heating units to supply the heating require ments. These reheating units may be located in the various branch ducts to the different rooms, each under control of its individual room ther mostat, or individual ducts may be run to the various rooms from the ' central unit. In this case reheater coils are provided to maintain a predetermined temperature in a warm air chamber. Each room.duct is connected to this warm air chamber and to the tempered air supply, and through the action of a room thermostat on a gradual-acting doubler mixing damper the proper proportions of warm and tempered air are secured to maintain desired conditions in the room. In all types of central fan systems, the outdoor air damper is usually opened and closed by a damper motor controlled from a manual switch Pitot room n thermostat'"'^ I Fig. 3. Control of Ventilating System with Air Washer Using Pilot Thermostat or by. a relay in the fan motor circuit, so arranged that when the fan motor is started, the relay causes the damper motor to open the outdoor air damper. . :. Recirculating and vent dampers may also be opened and closed by means of damper motors controlled from remote locations. Generally these damper motors are positive acting and are either completely open or closed. However, in some cases, where part outdoor air and part recirculated air is desired, it is advantageous to control the dampers so that definite proportions of damper opening area exist. In some instal lations the control of outdoor air and recirculating dampers is under the command of a thermostat at the intake to the conditioner, in which case the proportions of outdoor and recirculated air are fixed by the resultant temperature of their mixture. This arrangement tends to reduce the amount of outdoor air used as the outside temperature is lowered. The operation of. a central fan system during the heating cycle often results in unfavorably low relative humidity and the provision and control of humidity becomes an important factor of the system. If water spray humidification is used, control may be effected by a humidity con- 656 CHAPTER 38. AUTOMATIC CONTROL ,, .trailer actuating a control valve in the water supply to the sprays. If steam humidification is used, either of the steam jet type or of the steam heated evaporating type, the flow of steam may be controlled from the humidity controller in the ventilated space. Where an air washer is used, approximate control of humidity may be obtained by maintaining the air temperature in the air washer at a predetermined desired dew-ppint temperature. For example, the dew-point temperature at 70 F and 40 per cent relative humidity is 45 F. Therefore, if the air temperature is maintained at 45 F as it leaves an air washer (assuming it is fully saturated) and then is heated to 70 F, it will have a relative humidity of 40 per cent. If it is desired to maintain these conditions in a given space, the air temperature can be raised to any necessary point, say 120 F (at which the relative humidity will be only 9 per cent). When the heat in the air has been dissipated, the space temperature being maintained at 70 F, the relative humidity will be 40 per cent. Whenever moisture is being added to the air during the heating cycle by the use of a spray or any other means, a considerable amount of care must be used in order to prevent frost from collecting on the windows due to the air being reduced below its dew-point at the inside surface of the windows. _ Cooling Cycle Central fan cooling systems are divided into two general groups based upon the methods employed to control the temperature and humidity of the treated space. Cooling normally involves the removal of moisture from the air, and to accomplish this end the temperature of the air must be lowered below the dew-point. The air at this low temperature must then be treated or introduced into the room in such manner as to avoid uncomfortable cold drafts. In the first group the air is supplied from the conditioner after being cooled and dehumidified to a fixed temperature and humidity and then before entering the treated space is reheated. This is accomplished either by passing the air through coils heated with steam; hot water,, or other heating medium, or the air from the conditioner is mixed with recirculated air before entering the conditioned space. In the second group are those systems which use the treated space as a mixing chamber, the air being supplied to it at the temperature and humidity leaving the conditioner and depending upon diffusion in the conditioned space to give ultimately, the correct conditions. In these systems the temperature and humidity of the treated space are measured and govern, through control of the cooling means, the temperature and the humidity of the air leaving the conditioner. In Fig. 4 is represented one of the most simple central fan types of cooling system. Thermostat T measures the temperature within the treated space and operates to start and stop the refrigeration compressor or to control the supply of refrigerant to the cooling unit as required to maintain a fixed temperature in the space. There are three general methods for the control of relative humidity in central fan cooling systems, which are: 657 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 1. By provision for limiting the relative humidity in addition to the temperature at a definite point. When this method is used, either temperature or humidity may demand operation of the cooling source regardless of whether or not the other factor has been exceeded. The use of a high limit humidity control in this manner is desirable during conditions of high relative humidity but its operation may cause excessive cooling unless some method of reheating is employed. 2. By the maintenance of a fixed effective temperature. By this method, a definite relation is maintained between temperature and humidity, and sensible cooling is done whenever possible instead of the removal of latent heat in the form of moisture. 3. By the maintenance of a fixed dew-point in the air discharge. This method usually provides for the control of relative humidity within the space being conditioned between reasonable limits, but does not take into consideration any change in the latent heat , load, as compared to the sensible heat load. The necessity for varying inside temperature conditions in accordance with changes in outdoor conditions on many types of installations is important. A control system is shown in Fig. 5 where the temperature of the treated space is adjusted according to the outdoor temperature. Thermostat 7\ measures the outdoor temperature and thereby auto matically determines the inside dry-bulb temperature control point. Thermostat Tt in the conditioned space measures the temperature of that space and controls the refrigerant to the cooling coil so as to maintain the temperature in the space being conditioned at the point which has been set up by thermostat 7\. . It is usually found desirable to adjust the indoor temperature between available limits with the outdoor temperature all of which is fully described in Chapter 3. Various combinations of control may be applied to cooling systems to secure desired relationship between outdoor temperature and resultant indoor temperature and humidity. All Year Systems An all year central fan conditioning system consists of the combination of a ventilating system and a cooling system. During certain seasons of the year, it is sometimes possible to control 658 CHAPTER 38. AUTOMATIC CONTROL ,, the dew-point of the air discharged from an air washer by regulating the relative quantities of outdoor and return air. The use of this method for controlling the outdoor and return air dampers may also provide for automatic change-over from the heating to cooling cycles, providing thereby for the maintenance of a fixed dew-point temperature in the airdischarge during both cycles. . Complete automatic control of all year systems incorporates an auto matic change-over between the cooling and heating cycles. If the instal lation necessitates operation of manual switch or other device to change over, between the heating and cooling cycles, then the control system is semi-automatic. The full automatic change-over between cycles becomes particularly desirable in the early and late portions of the cooling and heating seasons when heating is required during the early and late portion of the day and cooling may be required during the middle of the day. A system for the control of an all year conditioning system providing for automatic change-over from the cooling to heating cycles is illustrated in Fig^ 6. I l.Room thermostat Insertion j-- thermostat ^ j ; | Outdoor air I I $ I--------- 1^ 1 1 \\___ i X 1 Cooling 1 coil Fan 1 1 /_________________ SCH' Control valve f -Refrigerant supply Fig. 5. Diagram of Compensated Cooling System Control During the heating cycle, thermostat Ti in the return air or room measures the temperature of the conditioned space and modulates control valve Vi which, in turn, modulates the flow of steam to the heating coil so as to maintain a fixed temperature in the space. Humidity control Hi measures the relative humidity in the space being conditioned and opens control valve Fs so as to admit water to the sprays whenever moisture is required in the air. During the cooling cycle, thermostat Ts in the return air measures the temperature in the space being conditioned and modulates control valve Fj which, in turn, modulates the flow of water to the cooling coil so as to maintain a fixed temperature in the space. Humidity control H% measures the relative humidity in the space being conditioned and then assumes command of control valve Fs whenever the relative humidity exceeds a predetermined amount. During the heating cycle thermostat Tt acts as a low limit. It assumes command of control valve Fi whenever it is necessary to prevent the air 659 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 discharge temperature from falling below a minimum point. Thermostat Tt may also be arranged to act as a low limit during the cooling cycle if the conditions of the installation make it desirable. Thermostat Tt installed in the inlet to the conditioner controls damper motor Mi which in turn regulates the relative quantity of outdoor and return air admitted to the system. This damper action may be provided with a minimum setting of the outdoor air damper so that a minimum fixed requirement of outdoor air will be insured for ventilating purposes. Humidity control Iii measures the outdoor air relative humidity arid prevents the outdoor air damper from opening beyond its minimum Fig 6 ' Diagram op Complete Automatic Control All Year Air Conditioning System position whenever the outdoor air relative humidity exceeds a pre determined point. When the fan is stopped, relay R positions damper motor Mi so as to close the outdoor air damper. Thermostat 7\ must be set at a lower temperature than thermostat Tt in order that each may assume command upon the fall or rise respectively of the temperature of the return air. As an example, Ti might be set at 72 F and Ti at 76 F. When the temperature of the return air approaches 72 F, it would indicate that a change had taken place from the cooling to the heating cycle and when the return air approaches 76 F, it would indica'te that a change has taken place from the heating to the cooling cycle. . UNIT SYSTEMS A unit system provides for the same functions as a central fan system except that the actual conditioning is usually done within the space being conditioned instead of at some central location outside of the space. The 660 CHAPTER 38. AUTOMATIC CONTROL automatic control problems, therefore, become exactly the same as for central fan conditioning systems except that compactness, ease of instal lation and control cost often assume somewhat more importance. Because of the usual segregated location of unit equipment throughout a building and its consequent lack of competent supervision, complete automatic control is essential to its satisfactory operation. Unit Heaters In its simplest form, unit heater control consists of a room thermostat the function of which is to start the unit heater motor when heat is required and shut it off when the demand is satisfied. With this limited control, it is possible in some instances that, with no steam available at the heater, the operation of the fan at the command of the thermostat would cause objectionable drafts. To prevent this occurrence, limit controls are available which will prevent the operation of the fan at the command of the room thermostat except when steam is available, as determined by the temperature of the steam or return pipe or the pressure of the steam supply. In some cases it is desirable to operate the unit heaters continuously for circulation of air where, due to the type of installation, cold drafts will not result therefrom. In such instances the room thermostat regulates the supply of steam to the unit through a control valve in the steam supply line and the unit heater motor operation is manually controlled. Where several unit heaters serve a limited area, they may be grouped for purposes of automatic control, and several heaters placed in operation at the command of one thermostat. By properly grouping the units which will operate together, the benefit of zone control can often be obtained with a minimum of control equipment. Where such group operation is utilized, the thermostat and limit control usually function through a relay, as the combined load of the several motors may exceed the current capacity of the thermostatic control device. Cooling Units The recommended form of temperature control for the-cooling unit contemplates the continuous operation of the cooling unit fan with auto matic two position regulation of the compressor or cooling coil as deter mined by a room thermostat or by a temperature controller measuring the temperature of the return air as it is taken into the cooling unit. Such operation insures continuous circulation of the air in the room served by the cooling unit, and in addition to providing the cooling effect due to the moving air, this circulation overcomes the tendency of air to stratify. Thus, as this temperature tends to rise, the temperature controller will open the valve supplying either refrigerant or cold water to the cooling unit coil or start the compressor. . Cooling units may also be controlled by arranging the room thermostat to start and stop the fan motor or by a combination of motor and refrig erant control. A humidity controller may be used in conjunction with the thermostat as a high limit control to permit the cooling and dehumidifying of the air 661 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 whenever the relative humidity rises above some predetermined point such as 60 per cent even though the thermostat is satisfied. This control is desirable on damp days or in conditions where the humidity load may become excessive, but its operation will result in excessive cooling unless some means of reheating is provided. Unit Ventilators There are various types of unit ventilators available but in general all types are designed to draw air from the outside or to mix outside and recirculated air, heat it and introduce it into the room under control of a thermostat. In the application of control to unit ventilators the essential require ment is that the action be graduated to prevent sudden changes in the temperature of the discharged air and where direct radiation is used in conjunction with the unit that the cycle of control be so arranged that steam will be admitted to the direct radiation only when the unit is unable to carry the heating load. This arrangement prevents the unit from delivering air at low temperatures to offset the overheating effect of the direct radiation and results in the delivery of a higher percentage of tempered air. There are two general types of control applied to unit ventilators as follows: 1. The mixing or by-pass damper type of unit is provided with a damper, equipped with a damper motor, which, under control of the thermostat, passes air through and around the heating element in such proportion as to maintain a uniform room tempera ture, the two streams of cold and tempered air being mixed and diffused at the ceiling. A control valve may also be used on the steam supply to the heating element of the unit and should be arranged to throttle the steam supply when the damper approaches a position to by-pass all of the air. . The outside air damper of this type of unit is usually provided with a damper motor and controlled by a remote manual switch to assume either a fully open or fully closed position. 2. The recirculating type of unit ventilator is equipped with a control valve on the steam supply to the heating element of the unit and with a damper motor on the outside air-recirculating air damper, both under the control of the room thermostat. Some units are so arranged that a mixture of outside air and recirculated air passes through the heating element and others so that only the recirculated air is heated. The fundamental requirements of control as applied to this type of unit is that the steam supply to the direct radiation, the steam supply to the unit ventilator and the mixing of outside and recirculated air be accomplished in a definite cycle or sequence to meet the requirements of the particular unit used and differs from the mixing damper tyj>e of unit in that the percentage of outside air and recirculated air delivered by the unit is determined by room temperature. The damper motor is sometimes arranged so that a fixed minimum quantity of outside air is delivered continuously as soon as the room has reached a predetermined temperature. A limit thermostat, either in the mixing chamber or in the discharge of the unit, is sometimes used in conjunction with the room ther mostat, so arranged that the action on either the control valve or the dampers, or both, is stopped when a predetermined minimum temperature has been reached in the unit discharge, to prevent delivery of air at a lower temperature. For additional information on the control of unit ventilators when installed and operated under various types of applications refer to Chapter 22. 662 CHAPTER 38. AUTOMATIC CONTROL . All Year Conditioning Units It is desirable to provide for automatic change-over between the cooling and heating cycles in the control system for all year conditioning units because of the probable necessity of changing over a large number of units if done manually. A control system for an all year conditioning unit providing for the automatic change-over is shown in Fig. 7. Operation of the control equipment is as follows: 1. During the Heating Cycle. Combination controller Ti measures the temperature in the space being conditioned and opens control valve V% so as to admit steam to the heating coil whenever heat is required so as to maintain a fixed temperature in the space. Combination controller T, also measures the relative humidity in the conditioned space and opens . Combination thermostat Fig. 7. All Year Air Conditioning Unit with Complete Automatic Control control valve Vi so as to admit water to the sprays whenever moisture is required in the space. 2. During the Cooling Cycle. Combination controller T* measures the temperature and humidity in the conditioned space and opens refrigerant control valve Vs, thereby admitting; refrigerant to the cooling coil when ever cooling is required to maintain the temperature or relative humidity within predetermined maximum limits. The temperature control point of controller Ti must be set at a lower {Joint than that of controller Tt in order to provide for the automatic change-over between the cooling and heating cycles. As an example, controller r, might be set at 72 F and controller at 76 F. As the temperature in the space approaches 72 F, it would indicate a change from the cooling to the heating cycle and when the temperature in the space approaches 76 F, it would indicate a change from the heating to- the cooling cycle, and the corresponding controllers would assume command. In the same way, the relative humidity control point of controller Ti would be set at a lower point than that of controller T2. As an example, Ti might be set at 35 per cent and Tj at 60 per cent. 663 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CONTROL OF AUTOMATIC FUEL APPLIANCES It is essential that automatic controls be used with oil burners, gas burners, and stokers in order to maintain even temperatures and provide safe and economical operation of the heating plant. There are many types of burners and many types of automatic control, and it is essential that the proper type of control equipment be selected to fulfill the require ments of the burner equipment and its application. Combustion regulation equipment should be used on the larger com mercial and industrial applications to control the secondary air supply and thereby provide for economical operation. This type of control wil,l usually consist of a pressure regulator which measures and controls the pressure over the fire and which thereby indirectly regulates the carbon dioxide percentage in the flue gas. On all automatically-fired steam boilers it is advisable to provide control equipment which will stop the burner operation in case the boiler water line falls below a predetermined level of safety. . Thermostats used to control automatic fuel appliances may be provided with clock mechanisms which will operate to maintain lower temperatures during night hours for economy of fuel. Oil Burner Controls In the normal oil burner installation as encountered in residential and small commercial installations, the burner operation is frequently regu lated by electric controls and primarily governed by a room thermostat. It is essential that a limiting control be incorporated in the control system to prevent the temperature of the heating medium from exceeding any predetermined safe maximum. The type of limit control selected will depend on the type of the heating system. In a warm air furnace instal lation, a limit control would be used, reacting to the temperature of the heated air in the bonnet of the furnace; in a hot water system a control reacting to the temperature of the water in the boiler; and in a steam system a Control reacting to the pressure of the steam in the boiler. In addition to the normal control of the burner from the room ther mostat and limit control, it is necessary that a combustion safety device be used to prevent operation of the burner under hazardous conditions. The oil fire is automatically ignited by means of gas, electric spark or incandescent element and the combustion safety control acting through a sequence device permits the burner operation only when the fire is prop erly established as the burner starts up. A further function of the com bustion safety control is to react to any major disturbance in the flame during the running operation, shutting down the burner and preventing the discharge of unburned fuel if for any reason the flame is extinguished. Gas Burner Controls In the case of the domestic burner, full automatic operation is the normal requirement and the burner is started and stopped at the com mand of a room thermostat which, in turn, opens and closes a control valve in the gas supply line. Modulating controls and controls providing a high and low fire are also available for gas burners. For purposes of preventing abnormally high temperatures in the bonnet of gas-fired 664 CHAPTER 38. AUTOMATIC CONTROL furnaces or in the temperature of the water in gas-fired hot water heating boilers or excessive pressures in gas-fired steam boilers, temperature and pressure limit controls are used. Ignition is normally secured through the use of a gas pilot flame and a safety device is provided, utilizing the heat of the pilot flame in such a manner that if the pilot light is extinguished for any reason, the main gas valve cannot be opened. For satisfactory and economical operation, all automatically-fired gas burners should be equipped with pressure regulators on the gas supply line. Stoker Controls Domestic stokers are normally placed under command of a room thermostat for primary operation subject also to the command of a limit control to prevent their operation when conditions in the boiler or furnace exceed predetermined safe maximums. Utilizing coal as fuel, automatic ignition is not provided and the stokers, once ignited, maintain their fire, merely changing the rate of combustion by changing the draft and the rate at which the coal is fed. Thus, at the command of the room ther mostat the stoker motor is started, driving a forced draft fan and fuel feeding mechanism. The rate of combustion is thus increased and this operation continues until the thermostat has been satisfied when the motor is stopped and the fuel in the combustion chamber continues to burn at a slow rate with reduced draft. At certain seasons of the year, the operation of the stoker under the requirements of the thermostat may be so infrequent that there is a possibility of the fuel in the combustion chamber burning out or the fire going out between operations. To prevent this occurrence, automatic controls may be utilized to operate the stoker independently of ther mostat requirements, sufficiently to sustain the fire either through a timing device functioning for short periods at predetermined intervals or through a temperature control device reacting to minimum stack or boiler temperatures. Control may also be utilized to prevent stoker operation and the delivery of coal into the combustion chamber in the event that the fire has gone completely out. This control is governed normally by the stack temperature and shuts down the stoker after a predetermined minimum stack temperature is reached. RESIDENTIAL CONTROL SYSTEMS The control installation in a residence may vary from the simple regulation of a coal-fired heating plant to the completely automatic all year air conditioning system. Residential installations with automatic fuel burning appliances, such as oil burners, gas burners or stokers, are normally equipped with single room thermostat, limit and safety controls as outlined above under Control of Automatic Fuel Appliances. Coal-Fired Heating Plant Control in the normal coal-fired domestic heating plant consists of regulating the combustion rate in accordance with requirements. This function is accomplished by a spring or electric-driven damper motor which under the command of a room thermostat and through chain linkage, operates the draft and check dampers of a boiler or warm air 665 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 furnace. Such installation should be protected against excessive tem perature or pressure by means of a limit control serving to check the fire when temperature or pressure conditions at the boiler or furnace reach a predetermined maximum. ' Ail Year Domestic Hot Water Supply Hot water or steam heating boilers with automatic fuel burning ap pliances can be used for all year heating of domestic water supply. The fuel burning appliance in this case is controlled from the temperature of water or pressure of steam in the boiler to maintain uniform boiler con ditions and domestic hot water is heated by means of an indirect heater. The heating of the residence is normally governed by means of a ther mostat which operates a control valve in the flow line of a gravity hot water or a steam system, or controls the operation of a circulating pump in a forced circulation hot water system. Air Conditioning Systems Residential air conditioning systems are of various types normally including a heating source and a motor-driven fan for circulating air. In addition, such installations may involve spray-head equipment, the purpose of which may be only to supply humidity, or which, in some instances, are of greater capacity and serve not only to humidify but to wash the air passing through them. It is also common practice to include dry filters to aid in air cleaning. Such installations distribute suitably heated and humidified air during the heating cycle, and during the summer or cooling cycle may be used effectively as conditioners if the washer unit is supplied with water at suitable temperature or if such an installation is equipped with other refrigeration means. . During the heating cycle the regulation of temperatures is normally one or the other of the problems previously discussed in connection with the various types of heating sources described, such as the oil burner, gas burner, stoker or the coal-fired heating plant under-automatic control. Regulation of the humidity during the heating cycle is normally accom plished by opening and closing a solenoid water valve supplying water to the spray-heads, the solenoid valve being under control of a room type humidity control. In the average installation the fan is permitted to run only during such intervals as the thermostat is calling for heat or at the command of a limit control to prevent the overheating of the bonnet of a warm air furnace. The limit control should also prevent the operation of the fan at the command of the thermostat until the circulating air tem perature has increased to a predetermined point. When cooling equipment is provided in such installations, control during the cooling cycle will be an adaptation of the control principles described for central fan systems selected for the type of cooling equip ment utilized. The selection of automatic control equipment for residential air con ditioning systems is just as important as for commercial installations. Fewer controls are generally used and systems are usually less com plicated except in the case of a very large residence installation when the control system may become as complete as the commercial installation. 666 CHAPTER 38. AUTOMATIC CONTROL CONTROL OF REFRIGERATION EQUIPMENT The most common means of providing cooling for air conditioning may be divided into four general classifications as follows: Compressor Type Refrigeration Refrigeration compressors may furnish refrigerant to direct expansion cooling coils through which air is being passed, or to coils in cooling tanks through which water is passed which is then pumped to air washers or cooling coils through which the air is passed. In either case the compressor motor may be started and stopped in order to meet the demand for refrigeration or a pressure controller may be used to regulate the low side or suction pressure of the compressor. When the latter method is used, the flow of refrigerant to cooling coils may be regulated by the opening and closing of a solenoid refrigerant valve at the command of a temperature controller or thermostat. A high pressure cutout as an individual unit or in combination with either a temperature or pressure controller provides a safety feature against the development of excessive pressures on the high side of the compressor. Ice Cooling When ice is used for the cooling or dehumidification of air, it is usually placed in bunkers and water is sprayed over it. This water, after being cooled, may be used in air washers or surface cooling coils and is usually returned to the bunker for additional cooling after being used. Control of the water temperature leaving the cold water tank may be maintained by a temperature controller, which measures the temperature of the water in the tank and modulates a control valve in a by-pass which permits a portion of the return water to return directly to the tank instead of passing through the sprays. Vacuum Refrigeration A vacuum refrigerating system consists of an evaporator, compressor, condenser and auxiliaries. The refrigerant used is water, and water vapor (steam) is the power medium. Water which has been passed through an air washer or cooling coil is sprayed directly into the evaporator or water cooler where it is cooled by its own evaporation. A condenser is attached directly to the compressor discharge and its function is to recondense the water vapor drawn from the evaporator, plus the steam which supplies the energy for compression. The temperature of the cold water leaving the flash chamber should be measured by a temperature controller which will in turn operate a twoposition or positive-control valve installed in the steam line to the jet so as to permit steam to flow only when cooling is required. If city water is used in the condenser, the amount of water should be modulated according to the demand as measured at the condenser outlet by means of a tem perature controller and control valve. 667 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Refrigeration, by Well Water When well water is available in sufficient quantities at low temperatures during the cooling season, it may be pumped directly to air washers or cooling coils. Control is usually effected through control valves on the water supply to the cooling unit actuated by temperature or humidity controllers, or both, located either at the outlet of the conditioner or in the conditioned space. INDUSTRIAL PROCESSES There are many industrial processes requiring automatic temperature and humidity regulation. The control equipment operates on the same principles that have been described, but it is often especially designed for each particular process. Each installation, or the installation for each process, is likely to be a problem peculiar-to that process. 668 Chapter 39 MOTORS AND CONTROLS Direct Current Motors, Alternating. Current Motors for Single Phase and Polyphase, Special Applications, Classification of Motors, Manual Control, Automatic Control, Pilot Controls, , Direct Current Motor Control, Squirrel Cage Motor Control, Multispeed Motor Control, Slip Ring Motor Control, Single Phase Motor Control . THE electric motor, ' available in many different types suitable for various services, is now the most widely used form of prime mover. The equipment for starting, controlling and protecting these motors varies with the type and with the functions it is desired to attain. . Motors used for heating, ventilating arid air conditioning applications may be divided into two general classifications as follows: ' ' 1. For use with direct current. 2. For use with alternating current. . DIRECT CURRENT MOTORS There are three types of direct current motors available: 1. Shunt Wound. 2. Compound Wound. 3. Series Wound. . Shunt Wound motors being suitable for application to fans, centrifugal pumps, or similar equipment where the amount of starting torque required is relatively small, are used for the majority of applications in the field of heating, ventilating and air conditioning. They may be used on recipro cating pumps and compressors, if started under unloaded conditions. Compound Wound motors are required for application to compressors, stokers, reciprocating pumps when started under loaded conditions, and also when applied to similar equipment where high starting torque is required. Whenever frequent starting makes high starting and accelerat ing torque desirable, or where sudden changes of load are encountered, compound wound motors are used. . Series Wound motors find only limited application in a few special cases and are available in only a limited range of sizes. 669 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Speed Characteristics Direct current motors are available with speed characteristics of four types: 1. Constant speed. 2. Adjustable speed. 3. Adjustable varying speed. 4. Varying speed. Constant Speed motors may be shunt wound or compound wound. Shunt wound motors have a nearly flat speed-load characteristic, with' a regulation of 15 per cent for up to % hp, 12 per cent for one to 5 hp and 10 per cent for lx/i hp and larger, based on full load speed. Compound wound motors have a speed regulation over the range from full load to no load of not more than 25 per cent, based on full load speed.' Adjustable Speed motors are usually shunt wound since it is impractical to maintain the proper relation between the shunt and series fields of compound wound motors when wide variations of the field strength are required to obtain the speed adjustment. . Adjustment of the speed of shunt wound motors is obtained by field control on motors rated at M hp and larger, with the minimum or base speed at full field strength and higher speeds at reduced field strength (obtained by adding resistance in the field circuit). The speed regulation from no load to full load will not exceed 22 per cent for 2 to 5 hp; nor 15 per cent for 7)4. hp and larger. Below 2 hp, the regulation may exceed 22 per cent. If closer speed regulation is required, specifically wound motors must be obtained. Practically constant horsepower output is obtained at all speeds up to a ratio of 2 to 1. For higher speed ratios, the horsepower rating at the minimum speed is less than at the maximum speed, this difference varying with the speed ratio. High efficiency is maintained-over the entire speed range. Most listed constant speed motors are suitable for operation up to a speed ratio of 2 to 1 by the use of proper control equipment. Adjustable Varying Speed motors may be either shunt or compound wound and speed adjustment is obtained by adding resistance in series' with the armature. The speed thus obtained is always below the rated full-field speed. Any standard shunt or compound wound constant speed motor may be used in conjunction with the proper armature resistor. The usual range of speed reduction is 50 per cent. The speed obtained for any setting of the resistor depends on the load of the motor and will vary with this load. The speed regulation at high speed is comparable to a constant speed motor, but becomes poorer as the speed is decreased. ' When operating at reduced speed, an increased torque requirement which the motor could easily handle at rated speed is easily sufficient to stall the motor; for example, a motor operating at two-thirds speed would be stalled by a torque about 50 per cent in excess of the normal requirement. The efficiency of the motor is reduced as the speed is reduced, since the 670 CHAPTER 39. MOTORS AND CONTROLS loss in the resistor is greater at lower speeds. Speed reduction by armature control is usually selected where: , 1. A wide speed range is not required. 2. Close speed regulation is not necessary. 3. Operating time at reduced speed is short. 4. Operating load at reduced speed is small so that the reduced efficiency can be ignored. ,. 5. The rating is less than 1 hp. Varying Speed motors are series wound and the speed varies with the load on the motor. They should be used where: 1. The load is practically constant or increases with speed. 2. The motor can easily be controlled by hand. They should not be used where there is a possibility of operation without load or at a reduced load, as the speed of the motor may become dangerously high. For shunt wound motors with full field strength, the starting torque varies almost directly with the starting Current, which is dependent on the resistance in the armature circuit. With varying positions of the starting rheostat, it is possible to obtain a wide range of starting torque, within the limits of starting current permitted by the power company. A compound wound motor requires somewhat less current for the same starting torque. The maximum torque of shunt, series, and compound wound motors is limited by commutation. ' ALTERNATING CURRENT MOTORS Alternating current motors may be divided into two main groups, namely, (1) those operating on single phase current, and (2) those oper ating on polyphase current. 1. Single phase motors are available in four common types: a. Capacitor motors. 1. Full capacitor. 2. Capacitor start-induction run. b. Repulsion induction motors. c. Repulsion start, induction run motors. d. Split phase motors. " 2. Polyphase (2 or 3 phase) motors are available in four common types:. o. Squirrel cage induction motor. b. Automatic start induction motor. c. Slip ring, wound rotor induction motor. d. Synchronous motor. Where the public utility supplying the current determines that a particular installation should be served with polyphase current, it is generally understood that the major portion of the motors will be for polyphase current, although it is. commonly acceptable for the smaller motors to be' single phase. This will limit the use of single phase current to the smaller motor ratings and the polyphase to the larger motors. Domestic and semi-commercial installations will invariably be single phase. 671 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Single Phase Motors - Capacitor type motors are available in ratings up to 10 or 15 hp for general purposes. These motors are recommended for pumps, compressors and fan duty including housed centrifugal fans and propeller fans. The general purpose motor is commonly known as a high torque capacitor motor having approximately 300 per cent starting torque with normal, current and having a different value of capacitance for starting and running which is automatically changed over by a mechanical or electrical means. . . Capacitor motors for fan duty are usually divided into the open high torque type for belted fans and the totally inclosed non-ventilated low torque type for propeller fans mounted directly on the motor shaft. The open low torque capacitor motor may be used with small centrifugal fans mounted on the motor shaft. , Although the motors for beltedfans are called high torque, the available starting torque is somewhat less than the torque of the general purpose motor and the slip at full load is approximately 8 per cent. With this larger amount of slip, adjustable speed down to 60 or 70 per cent of rated speed may be obtained by line voltage variation. Motors for propeller fan drive may be supplied with sleeve bearings to obtain greater quietness in the smaller sizes where the fan thrust does not exceed approximately 25 lb. For larger fans, thrust ball bearing motors should be used. Low torque capacitor motors have approximately 50 per cent starting torque and do not change the value of capacitance from start to run. Capacitor motors with high slip may have taps brought out from the main winding which when connected to the line, give a second speed of from 65 to 70 per cent of the normal speed. This type of motor must be specially designed for the individual fan, otherwise the correct low speed will not be obtained. Care should be exercised in applying it to centrifugal fans where restriction to the air flow through the use of adjustable dampers changes the motor load and consequently the speed. -This.same effect is also found in transformer speed controllers, however,-a series of trans former taps allow for a selection which partially overcomes the effect of change in motor load. Capacitor start-induction run motors are usually confined to the smaller horsepower ratings and differ from the capacitor motors by having no running capacitor. The value of starting capacitance used may vary with the different types of applications involved. These motors may be used for practically any of the applications met in air conditioning. However, consideration should be given to the fact that they are not as quiet as a capacitor motor. Repulsion induction motors start as repulsion motors and operate under full speed as combined repulsion and induction motors through the in herent characteristics of the motor which has, in addition to the wire winding with commutator, a buried squirrel cage winding. No additional switching devices are required to change over from start to run. This and the repulsion motor described below may be used for constant speed drives where high starting torque is required and where commutator and brush noise is not a factor. : 672 CHAPTER 39. MOTORS AND CONTROLS The repulsion start-induction run -motor starts as a repulsion motor, has a switching means for transferring from start to run which short circuits the commutator and permits operation under full speed as a . wound induction motor. This motor is suitable for applications similar to those for which the repulsion induction motor is used. . The split phase motor has a high resistance auxiliary winding in the circuit during starting which is disconnected through the action of a centrifugal switch as the motor comes up to speed. Under running con ditions, it operates as a single phase induction motor with one winding in the circuit. These units are available for the lower horsepower ratings and when equipped with a high slip rotor may be used for adjustable varying speed through line voltage control. Polyphase Motors - Squirrel cage induction motors are available in three types and a full range of sizes: 1. The normal torque, normal starting current squirrel cage motor has close speed regulation, high efficiency, high power factor, medium starting torque, high pull-out torque, and is suitable for general purpose applications. This motor has a large current inrush and a low starting current power factor. It operates with these characteristics only when started directly across the line on full voltage. When central stations require current limiting starting equipment on such motors, the starting torque is less. Current limiting hand operated starters are standard equipment. 2. The normal torque, low starting current squirrel cage motor has approximately the same torque as the normal current motor, but the starting current is about 20 per cent less than the normal torque motor on full voltage and ordinarily within the Edison Electric Institute locked rotor current limits on sizes up to 30 hp. This motor lends itself to automatic or remote control because no current limiting starting equipment is necessary up to and including 30 hp. A magnetic starter with low voltage and thermal relay overload protection gives the most satisfactory service. 3. The high torque, low current squirrel cage motor has a starting torque approxi mately 25 to 50 per cent greater than the normal torque motor on full voltage with starting current approximately 10 per cent less than the normal torque motor started on full voltage, but within the required limits on 30 hp sizes and smaller. These motors are also started directly across the line on full voltage through a magnetic starter or other approved starting device. These three types of motors are also available in two, three, or four speed designs with variable torque, or constant torque characteristics. Two speed motors may be either single, or two winding; three speed motors are single, two, or three winding; and four speed motors are two, three, or four winding. When a motor is wound with a winding for each speed, better operating characteristics may be obtained because no sacrifice is made for the other speed and operating characteristics ap proaching single winding motors may be expected. . Frequently, multispeed motors lend flexibility to an installation that cannot be obtained in any other way. Multispeed motors are started directly across the line through magnetic starting equipment with overload and low voltage protection and com pelling relays to insure starting on low speed regardless pf the ultimate running speed. Starting on low speed limits the starting current to the starting current of the low speed winding and consequently lowers the maximum demand. 673 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Table 1. Classification of Motors CURRENT TYPE 1. Shunt Direct 2. Compound Speed TERisncs Full Voltage Starting Torque Starting Current Hp Range Constant Speed Drives *Constant Medium Medium All Constant Tigh Dr Variable Medium (Ml Ttpb OP See Footnote* - ,' a) Fans and c) Centrifugal I'umps b) (c) 00 Reciprosating Pumps and freijuentorhand starting 3. Series Variable High Medium Small (d) Fans direct connected Poly phase 4. Squirrel Cage Constant Normal High All General Purpose 6-8 Times (o) Fans and (c) Centrifugal Pumps 5. Squirrel Cage Constant Normal Medium Torque 6. Squirrel Cage. High Torque Constant High Medium Medium (a) Fans and 5-6 Times Small Centrifugal Pumps Medium Medium 5-6 Times Small (ft) Reciprocating Pumps (e) and Compressors started loaded 7. Automatic Start Constant High High Torque Low 3 Times Medium (ft) Reciprocating Pumps (e) and Compressors started loaded 8. Slip Ring Wound Rotor Constant High Low All ' ..... () and Hoists 1-3 Times () Reciprocating with sec Pumps ondary (c) and Frequent control (e) or Hand Start 9. Synchronous High Speed . Constant Medium Medium Medium 5-7 Timesi Large (a) Fans and Cen trifugal Pumps 10. Synchronous Constant Low Low Speed . Low Medium (a) Reciprocating 3-4 Time.> Large Compressors start ing unloaded Single phase 11. Capacitor Constant High Normal Medium (6) Pumps and Small Compressors " Drives having medium or low starting torque and inertia (VFRi) such as fans and centrifugal pumps or reciprocating pumps and compressors started unloaded. ,. , . b. Drives having high starting torques, such as reciprocating pumps and compressors started loaded. c. Similar to (<*) except where frequent or hand starting (large WRl) requires a higher starting and accelerating torque.' d. Fans direct connected. e. Stoker drives. 674 K^ryvrr,. CHAPTER 39. MOTORS AND CONTROLS Current Table 1. Classification of Motors--(Continued) TYPE Speed Charac teristics Full Voltage Starting Torque Starting Current Hp Range Application See Footnote* Single PHASE 12. Capacitor Fan Constant High Medium Medium (a) Fans--belted Small 13. Capacitor Fan Constant Low Medium Medium (d) Fans;--direct Small 14. Capacitor Start Constant Any Induction Run Medium Medium () Fans Small () Pumps and Compressors 15. Repulsion Induction Constant High Medium Medium (a) Fans Small (A) Pumps and Compressors 16. Repulsion Start Constant High Induction Run Medium Medium () Fans Small () Pumps and Compressors 17. Split Phase Constant Medium and Adjusttable Medium Frac tional (a) Fans (A) Pumps and Compressors Adjustable Speed Drives 18. Shunt Field Adjustment Constant Medium Medium All Direct 19. Shunt Armature Variable Medium Medium All Resistor (a) Fans and (e) Centrifugal Pumps [a) Fans and [e) Centrifugal Pumps Poly phase 20. Squirrel Cage High Slip, Variable Medium Medium Medium small (a) Fans Tapped Winding 21. Squirrel Cage 1Variable High Slip, Trans former Adjust ment Medium Medium ! Medium <Small a) Fans 5'2. Squirrel Cage l Constant ] Medium Separate Wind- ] Multi- c r High ing or Regrouped 5>peed Poles ] -x>w !w a) Fans ft) Pumps and c) Compressors 675 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Casasot Table 1. Classification of Motors--(Concluded) TYPE Speed Chaaao- TEBOnCS Full Voltage 8racting Tosqos StASTING Current Hf Kangs Ttpb OF, Seb Footnote * Poly phase Single phase 23. Wound Rotor, Variable Slip, Ring, Ex ternal Secondary Resistance High 24. Capacitor High Variable High Torque Tapped Winding . 25. Capacitor Low Variable Low Torque Tapped Winding 26. Capacitor High Torque Trans former Adjust ment ' 27. Capacitor Low . Torque Trans former Adjust ment Variable Low Variable Low 28. Split Phase Constant Normal Regrouped Poles Low * All Normal Medium Low Medium Medium Low Low Frac tional Low Frac tional Normal Frac tional (o) Fans and (4) Centrifugal Pumps ' (a) Fans, belt (d) Fans, direct (d) Fans (d) Fans (d) Fans ' Oftea where the central station requires current limiting starting equipment for the normal torque, normal starting current motor, it is advisable to use the normal torque low starting current multispeed motor. High slip polyphase motors may be used for adjustable varying speed drives in a manner similar to that described for capacitor motors, with either a transformer speed regulator or tapped motor windings. It Is apparent from these motor characteristics that a squirrel cage motor may be selected for operating any air conditioning and allied equipment. Automatic start induction motors are constructed with two windings on the rotor, one of which is a high resistance, squirrel cage winding used in starting and gives a high starting torque approximately the same as the high torque, squirrel cage. A centrifugal mechanism within the motor switches to the second low resistance winding when the motor comes up to speed, thus obtaining running characteristics equal to the normal torque, normal current squirrel cage motor. The power factor of the starting current is high. Slip ring wound rotor motors are built for two classes of service, con stant speed and adjustable variable speed. The motors are identical in each case and use the same primary control, the only difference being in the secondary control. 676 CHAPTER 39. MOTORS AND CONTROLS Slip ring motors for constant speed service are used where high starting torque with low starting current is required for bringing heavy loads up to speed. The resistance is in the secondary or rotor circuit, only when starting, and is short circuited when the motor is up to speed. For adjustable varying speed service, part or all of the secondary controller resistance is in the circuit whenever the motor, is operating below full speed. The speed obtained with a given resistance in the secondary circuit is dependent on, and changes with the load on the motor. The horsepower developed by the motor is approximately pro portional to the speed, whereas the power required by the motor is practically the same at reduced speed as at full speed, hence the efficiency at reduced speeds is much lower than at full speed. Synchronous motors are ordinarily used only where there is a need for, or advantage in, obtaining power factor correction. It is necessary to consider each application as a special case which must be individually engineered, since for satisfactory operation, the combined moment of inertia of the compressor fly wheel and motor rotor must be correctly established. The general classification of motors used for heating, ventilation and air conditioning is shown in Table 1.. ' SPECIAL APPLICATIONS UgA few applications of motors may require special constructions such as splash proof, explosion proof, fully enclosed, and self-ventilated to meet hazardous or special duty conditions. These requirements are frequently encountered in certain industrial applications, in which cases it is neces sary to select the motors from the viewpoint of service conditions, as well as the required operating characteristics to meet the demands of the machines being driven. CONTROL EQUIPMENT FOR MOTORS In selecting control for alternating and direct current motors it is necessary to determine whether the installation is to be operated by manual or automatic control. The available controls and the function of each group of apparatus may be outlined as follows: 1. Manual Control: . To establish current. (1) Snap switch. (2) Knife switch. (3) Manually operated contactor. (4) Drum switch. ' " . Establish current and add overload protective device. (1) Snap switch with overload element. (2) Knife switch with fuse or thermal cutout. . (3) Manual contactor with overload protective device; also reduced voltage starting compensator. (4) Drum switch with overload protection. c. Establish current and add overload and low voltage protective devices. (1) Not used. (2) Not used. 677 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 (3) Manual contactor or reduced voltage compensator with overload and low voltage release. ,, (4) Drum switch equipped with latch coil to give low voltage release. 2. Automatic Control: a. To start on full voltage. (1) Without overload device. (2) With overload device. (3) With combination overload device and knife switch. b. Reduced voltage starting. (1) Primary resistance type starter. (2) Auto compensator type. ' (3) Reactance type. PILOT CONTROLS In selecting pilot control devices to operate in conjunction with either/ manual or automatic motor control, it is necessary that they be classified as follows: 1. Two Wire Control. Most thermostats, float switches, and pressure regulators, provide two wire control which gives low voltage release. A three position pilot switch can be used in connection with this method and thus provide manual control. With a low voltage (12 or 20 volt) control circuit it is desirable to use a low voltage thermostat. When this type of thermostat is used it will be found that a saving in the wiring cost results. When using the low voltage thermostat on a control circuit a relay and trans former panel should be used instead of the low voltage coil on the starter. 2. Three Wire Control. Momentary contact start and stop push button stations are usually furnished as standard accessories with automatic starters, which gives low voltage protection. This control cannot be used in combination with two wire pilot devices. In selecting manual control for an alternating or a direct current motor, the common practice is to locate the control near the motor. When the control is installed at the motor, an operator must be present to start and stop or change the speed of the motor by operating the control mechanism. Frequently manual control is employed only as a device to give overload protection and another device is employed to start and stop the motor. Manual control is used particularly on small motors which operate unit heaters, small blowers, and room coolers in an air conditioning system. In other cases manual control in the form of drums, when used with multispeed motors, is only used as a speed setting device with the starting and stopping functions operated automatically through thermostats, and pressure switches. . Because of the increasing complexity of air conditioning systems, heating, ventilating and air conditioning equipment is being operated on automatic control with less dependence on manual operation and regu lation. Automatic control of motor starters may be accomplished by the use of remote push button stations, by a thermostat, float switch, pressure regu lator or other similar pilot devices. An added advantage of automatic control is that the main wiring for the starter may be installed near the motor, while the starter may be operated by a control device located else where. In the majority of air conditioning installations, requiring motors 1 hp and larger, two or three phase alternating current is usually supplied. 678 CHAPTER 39. MOTORS AND CONTROLS DIRECT CURRENT MOTOR CONTROLS Air conditioning installations using direct current power are now only used where alternating current is not available. Direct current motors are always started through starters, which are devices using a resistance to be put in series with the armature circuit during starting only, the resistance being gradually cut out as the motor comes up to speed. The starting current is held within safe limits by the use of the resistance. The speed of a direct current motor may be regulated by the following methods: . 1. Speed regulation by field control--by using a device with resistance to be put in series with the field winding. After the motor has been started to be used to increase the speed of the motor above full field speed. 2. Speed regulation by armature control--by using devices with resistance to be put in series with the armature circuit to be used to reduce the speed of the motor below full field or normal speed. 3. Combinations of field and armature control, so that the starting, field control, or armature control may be combined in a single unit. Field control is usually preferred, depending on the size of the instal lation. For example, if a direct current motor were required with speed regulation between 1200 and 600 rpm, a choice of supplying a 1200 rpm motor with armature control or a 600 rpm motor with field control, both giving the same speed variation would be possible. While the 1200 rpm motor with armature control is lower in first cost than the 600 rpm motor with field control, the cost of operating the 600 rpm motor with field control is less and will save the difference in first cost over a period of time depending on the size of installation. A wide speed variation can be easily obtained in a direct current motor by using a combination of field and armature control. . SQUIRREL CAGE MOTOR CONTROL To meet the requirements of various drives of an air conditioning system, three types of squirrel cage, two or three phase motors may be used: ' 1. Normal torque, normal starting current. 2. Normal torque, low starting current. 3. High torque, low starting current. Because of the large current inrush of the normal torque, normal starting current motor, central stations usually require current limiting starting equipment on such motors above 5 hp. To meet the starting current requirements, manual or automatic current limiting starting com pensators are used. These compensators are equipped with 50, 65 and 80 per cent voltage taps, the 65 per cent tap being regularly furnished when the compensator leaves the factory. Motors 5 hp and smaller have starting currents within the requirements of central stations and manual or magnetic, full voltage control may be used. The normal torque, low starting current motor has a starting current which is approximately 20 per cent less than the normal current motor on 679 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 full voltage and well within the required current limits on 30 hp sizes and smaller. This motor, therefore, lends itself to across-the-line control because no current limiting equipment is necessary. In selecting motors for fans, pumps, or blowers, it should be noted that while the cost of the normal starting torque, low starting current motor is higher, the cost of full voltage control is lower, so that the total cost of low starting current motors with across-the-line control is lower. A magnetic starter with low voltage and thermal overload protection gives the most satisfactory service. These switches may be controlled by remote push button stations, thermostats, or pressure switches to meet the requirements of any particular installation. > The high torque, low starting current motor has a starting current approximately 10 per cent less than the normal torque, low starting cur rent motor when started on full voltage. These motors, most commonly used on compressor drive, can be started directly across-the-line with manual or magnetic starters. Adjustable varying speed motor control by terminal voltage regulation requires a tap-changing switch manually or magnetically operated. Such a control switch operates to alter the voltage applied to the motor by contacting different auto-transformer voltage-ratio taps or by changing the amount of resistance inserted in the primary or line circuit. MULTISPEED MOTOR CONTROL To make an installation more flexible, multispeed motors are available with two, three or four speed designs, with variable torque, constant torque or constant horsepower characteristics. Multispeed may be started by means of manual or magnetic starting equipment. When using automatic magnetic control with two, three, and four speed separate winding or consequent pole motors, control is obtained from a remote point by means of a push button^ master switch. The various speeds of the motor are obtained from the'master switch by simply depressing the correct push button, which is known as selective speed control. It is commonly used in the smaller theatre installations where the fan and motor is located backstage and the speed control is located in the lobby. . Magnetic multispeed motor controllers may also be provided.with a compelling relay which makes it necessary that the operator press the first speed button before regulating the motor to the desired speed. This assures the operator that the motor is always started at low, speed before the motor is adjusted to one of the higher speeds. Starting on. low speed limits the starting current to the starting current of the low speed winding, and therefore, permits the use of motors in sizes larger than ordinarily permitted by central stations for full voltage starting. Timing relays, which provide for automatic acceleration, may be used for control. With the automatic acceleration feature, it is only.necessary to press the button for the desired speed. The motor will always start in low speed and automatically step up to the desired speed. Where the change of speeds does not occur at regular intervals, and where it is only necessary to change from one speed to another to take 680 CHAPTER 39. MOTORS AND CONTROLS care of seasonal requirements, a manual drum speed selector may be used. This drum is used to select the proper motor speed while an automatic starter is used to start and stop the motor. The smaller size speed selector drums rated 10 hp at 220 volts and smaller may also be used as a motor starter to make and break the current, as well as, serving as a speed selector device. Reversible or non-reversible drums may be supplied depending on the requirements of the installation. In the large size drums, a separate contactor must be provided to make and break the current. The contactor may be any approved starter. Overload and low voltage protection may be accomplished by using a magnetic starter. No push button station is required, the handle switch on the drum having the same characteristics as a three wire push button station. In selecting two speed motors for fan, pump, blower, or compressor drive it will be found that the two winding motors are more expensive than the single winding. The control for two speed, two winding motors is more economical and the combined price of the motor and contactor is only slightly higher. Because of the better performance of the two speed motor and the factor of safety in having two independent motor windings, the increased cost is considered worth the difference. SLIP RING MOTOR CONTROL When close speed regulation and low starting current is required slip ring onwound rotor motors are used. Slip ring motors are built for two classes of service, constant speed and adjustable varying speed. The motors for the two classes of service are identical, the only difference being in the secondary control used with the motors. Control for both primary and secondary of a slip ring motor is required. The primary control for a constant or adjustable speed is the same type as used with squirrel cage motors. Manual or magnetic starters, acrossthe-line type, may be used depending on the installation. The starting current and starting torque of a slip ring motor are almost entirely dependent on the amount of resistance in the secondary control and in the manner in which the secondary control is operated. The National Electric Manufacturers Association has adopted service classi fications which allow a selection of resistors permitting a starting current on the first contact of resistance varying from approximately 25 per cent of full load current to approximately 200 per cent of full load current or more, and permitting the resistor to remain in the secondary circuit of the motor for a period varying from not more than 15 seconds during an interval of operation from 4 minutes to continuous. Speed regulation of a slip ring motor is obtained by inserting resistance in the secondary circuit and usually provides for a 50 per cent speed reduction when the motor takes its full rated current at normal speed. As resistors are supplied for both fan duty and constant torque duty, care should be taken in selecting the proper resistors. Slip ring motors when used with centrifugal pumps and fans should have fan duty resistors. Because of the low current inrush of the fan and pump 681 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 load a starting resistor NEMA classification No. 15 may be used. For speed regulation resistor, classification No. 93 should be selected. On a compressor drive using an unloader, a constant torque resistor classi fication No. 15 should be used. If the compressor is started under load, NEMA classification No. 56 or 76 are used. For constant torque speed regulation, resistor No. 95 is used. SINGLE PHASE MOTOR CONTROL Where three phase current is not available or where single phase opera tion is preferred, then single phase repulsion induction, capacitor type or multispeed single phase motors may be used. Since the starting currents of all single phase motors are required to be within the starting-current limits established by the local power-supply company, a suitable type of starter may be chosen from the following selection: X. Enclosed two pole manually operated motor starters with thermal overload protection. 2. Enclosed two pole automatic motor starter operated by a push button, thermostat or similar device, with thermal overload relay and low voltage protection. 3. A manual or magnetic resistance type starter with low voltage protection. 4. A manual or magnetic control lor pole changing motors and for adjustable varying speed motors using an auto-transformer or resistance in the primary circuit to obtain line (or terminal) voltage drop. In selecting across-the-line control for single phase capacitor type motors it is usually very desirable to use three pole across-the-line starters. Control for multispeed, single phase capacitor motors may be selected from tables on three phase rating when consideration is given to the increased current and the necessary switching of connections. 682 Chapter 40 PIPE AND DUCT INSULATION Heat Transmission by Radiation and Convection, Heat Losses from Bare and Insulated Pipes, Heat Losses from Ducts, Love Temperature Insulation, Insulation of Pipes to Prevent Freezing, Economical Thickness of Pipe Insulation, Under ground Pipe Insulation HEAT is transmitted to or from pipes and ducts by radiation and convection. The radiant heat transfer per unit area is independent of the geometrical shape, whereas the convected heat depends to a considerable extent on the shape factor. In many cases, it is desirable to calculate the rate of heat transmission from a surface by radiation and convection, as the total rate of transfer is different, for instance, from a heating installation than from a cooling installation with an equal difference in temperature between the surface and the surrounding atmosphere. HEAT TRANSMISSION BY RADIATION AND CONVECTION The heat transmission by radiation from a surface to the surrounding surfaces can be calculated from the well-known Stefan-Boltzman formula: where Sr = 17.4 X 10-" X P (7V - TV) . (1) qr = heat transmission by radiation, Btu per square foot per hour. p -- effective emissivity of surface and surroundings. Ti = temperature of hotter surface, degrees Fahrenheit absolute. Tj = temperature of cooler surface, degrees Fahrenheit absolute. The heat transmission by free or natural convection can be determined from the formula: where (117\)w (/fTv1 .)\-ul ^ qc - heat transmission by convection, Btu per square foot per hour. C -- a constant depending upon the surface shape. , D = diameter of pipe or circular duct or height of vertical wall, inches. (effect of diameter or height becomes constant at 24 in.) T av. = average wall surface and surrounding air temperature, degrees Fahrenheit absolute. dt = temperature excess, between wall surface and surrounding air, degrees Fahrenheit. 683 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 The radiation under black-body conditions, or for an emissivity of 1.0, is given in Table 1 for cold surfaces as low as -- 39 F to warmer surfaces as high as 139 F. The emissivities of a number of surfaces ordinarily encountered in engineering practice are shown in Table 21. For horizontal cylinders, the value of C = 1.016 has been well estab lished by various investigations. For vertical plates, the value of C = Table 1. Heat Transmission by Radiation for Black-Body Conditions'1 Expressed in Btu per square foot per hour Temp. Dbg F -30 -20 -10 0 0 59.3 65.2 71.4 78.0 -1 58.7 64.7 70.8 77.4 -2 58.2 64.1 70.1 76.7 -3 57.7 63.5. 69.5 76.0 -4 -5 57.2 62.9 68.9 75.4 56.7 62.3 68.3 74.7 0 +1 +2 +3 0 78.0 78.7 10 85.0 85.7 20 92.4 93.3 30 100 101 40 109 110 50 118 119 60 127 128 70 137 138 80 148 .149 90 159 160 100 170 171 no 183 184 120 196 197 130 211 212 79.4 86.5 94.0 102 111 120 129 139 150 161 173 185 199 214 80.1 97.2 94.8 103 112 121 130 140 151 162 174 187 200 215 +4 80.8 88.0 95.6 104 112 122 131 142 152 163 175 188 201 217 +5 81.5 88.7 96.4 105 113 123 132 143 153 164 176 189 203 218 -6 56.2 61.7 67.7 74.0 +6 82.2 89.4 97.2 105 114 123 133 144 154 166 178 191 204 220 -7 55.7 61.1 67.1 73.4 -8 55.2 60.5 66.4 72.7 +7 +8 82.9 90.2 98.0 106 115 124 134 145 . 155 167 179 . 192 206 221 83.6 90.9 98.8 107 116 125 135 146 156 168 180 193 207 222 -9 54.7 59.9 65.8 72.1 +9 84.3 91.7 99.6 108 117 126 136 147 157 169 182 195 209 224 ^Example: Radiation from walls of room at 32 F to surface at -- 25 F for effective emissivity of 0.95 = (102 - 62.3) 0.95 = 37.7 Btu per square foot per hour. , Table 2. Emissivity Values for Various Surfaces Surface 100 0.14 0.53 0.07 0.43 0.06 0.28 0.79 0.90 0.87 0.76 0.88 0.88 FTemperature. Deg 200 0.15 0.53 0.07 0.44 0.06 0.28 0.79 0.90 0.89 0.76 0.89 0.88 300 0.16 0.53 0.07 0.46 0.07 0.28 0.79 0.90 0.89 400 0.17 0.53 0.11 0.48 0.79 _0._90 'Heat Insulation in Air Conditioning, by R. H. Heilman (Industrial and Engineering Chemistry, Vol. 28. July 1936. p. 782). 684 CHAPTER 40. PIPE AND DUCT INSULATION 1.394 has been fairly well established. A value of C = 1.79 for horizontal plates warmer than the surrounding air facing upward and 0.89 for horizontal plates warmer than air facing downward is indicated by recent investigations2. The heat transmission by free convection from vertical walls 24 in. or more in height is given in Table 3 as calculated from Equation 2 for ambient air temperature of 80 F. The values in Table 3 will not be changed appreciably by a considerable change in air temperature for a given temperature excess. For instance, a change in air temperature from 80 to 40 F will increase the heat transmission given in Table 3 by only 1.3 per cent. Table 3. Heat Transmission by Free Convection for Large Vertical Surfaces Expressed in Btu per square foot per hour Temp. Deg F Temprratur.e Difference between Body and Surrounding Still Air at 80 F 0 10 20 30 40 50 60 70 80 90 100 110 120 130 0 0 4.4 10.4 17.4 25.0 33.2 41.8 50.6 59.9 69.4 79.4 89.2 99.4 109.8 i 0.3 4.9 11.1 18.1 25.8 34.1 42.6 51.5 60.8 70.3 80.4 90.2 100.4 110.9 2 0.6 5.5 11.8 18.9 26.7 34.9 43.5 52.4 61.8 71.3 81.4 91.2 101.5 112.0 3 1.0 6.0 12.5 19.7 27.5 35.7 44.3 53.4 62.7 72.3 82.4 92.2 102.6 113.0 4 1.4 6.6 13.2 20.5 28.3 36.6 45.2 54.3 63.7 73.3 83.3 93.3 103.6 114.1 5 1.8 7.3 13.9 21.2 29.2 37.4 46.1 55.2 64.6 74.3 84.2 94.3 104.7 115.2 6 2.3 7.9 14.6 22.0 30.0 38.3 47.0 56.1 65.6 75.3 85.2 95.3 105.7 116.3 7 2.8 8.5 15.3 22.7 30.8 39.1 47.8 57.1 66.5 76.3 86.2 96.3 106.7 117.3 8 3.3 9.1 16.0 23.5 31.6 40.0 48.7 58.0 67.5 77.4 87.2 97.4 107.8 118.4 9 3.8 9.7 16.7 24.3 32.4 40.9 49.7 59.0 68.4 78.4 88.2 98.4 108.8 119.5 Table 4. Free Convection Factors for Various Shapes Shapes Horizontal cylinders 24 in. in diam. or over. .... Long vertical cylinders 24 in. in diam. or over. Vertical plates 24 in. in heieht or over..................... Horizontal plates warmer than air facine upward. Horizontal plates warmer than air facing downward Horizontal plates cooler than air facine upward.. Horizontal plates cooler than air facine downward. Factor 0.73 0.88 1.00 1.28 v 0.64 0.64 1.28 Table 5. Free Convection Factors for Various Diameter Pipes or Various Height Plates Actual o. d., or height, in......... 1 Factor............................................ 1.88 Actual o. d. or height, in_____ 9 Factor........................................... 1.22 2 1.64 10 1.19 3 1.52 12 1.15 4 1.43 14 1.11 5 1.37 16 1.09 6 1.32 18 1.06 7 1.28 20 1.04 8 1.25 22 1.02 Transmission of Heat by Radiation and Convection, by Griffith and Davis (.Special Report No 9 1922, Department of Scientific and Industrial Research, His Majesty's Stationery Office, London. England)! 685 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Table 3 can also be used for calculating the free convection rate of transmission for various commercial shapes such as pipes and ducts. These calculations are simplified by the use of the factors in Tables 4 and 5. Table 4 gives factors by which the values in Table 3 must be Table 6. Heat Losses from Horizontal Bare Steel Pipes ' Expressed in Btu par hour per linear foot per degree Fahrenheit difference in temperature between the pipe and surrounding still air at70F . Nominal Pipe ( )Inches 120 F Hot Water 150 F 180 F 227.1 F (5 Lb) Steam 209.7 F (50 Lb) . 337.9 F . (100 Lb) Temperature Difference Vi 1 i ij4 2 2H 3 3pi 4 5 6 8 10 12 50 F 0.455 0.555 0.684 0.847 0.958 1.180 1.400 1.680 1.900 2.118 2.580 3.036 3.880 4.760 5.590 80 F 0.495 0.605 0.743 0.919 1.041 1.281 1.532 1.825 2.064 2.302 2.804 3.294 4.215 5.180 6.070 uof 0.546 0.666 0.819 1.014 1.148 1.412 1.683 2.010 2.221 2.534 3.084 3.626 4.638 5.680 6.670 140 F 0.584 0.715 0.877 1.086 1.230 1.512 1.796 2.153 2.433 2.717 3.303 3.886 4.960 6.090 7.145 157.1 F 0.612 0.748 0.919 1.138 1.288 1.578 1.883 2.260 2.552 2.850 3.470 4.074 5.210 6.410 7.500 227.7 F 0.706 0.866 1.065 1.324 1.492 1.840 2.190 2.630 2.974 3.320 4.050, 4.765 6.100 7.490 8.800 267.9 F . 0.760 0.933 1.147 1.425 1.633 1.987 2.363 2.840 3.215 3.590 4.385 5.160 6.610 8.115 9.530 Table 7. Heat Loss from Horizontal Bare Bright Copper Pipe Expressed in Btu per hour per linear foot per degree Fahrenheit between the pipe and surrounding still air at 70 F Nominal Pipe Size ( )Inches Vt Vt i \)i 1)4 2 2)4 3 3)4 4 4)4 5 6 8 Hot Water (Type K Copper Tube) 120 F | 150 F | 180 F | . 210 F Steam (Standard Pipe Size Pipe) 227TF (5 Lb) 297.7 F 1 337.9 F , (50 Lb) 1 (100 Lb) Temperature Difference , 50 F 0.180 0.236 0.290 0.340 0.390 0.490 0.580 0.680 0.760 0.940 1.020 1.160 1.460 80 F 0.210 0.275 0.338 0.400 0.463 0.525 0.675 0.788 0.888 1.000 1.200 1.375 1.725 110 F 0.218 0.291 0.354 0.418 0.473 0.600 0.709 0.848 0.946 1.045 1.255 1.410 . 1.820 140 F 0.229 0.307 0.373 0.443 0.507 0.628 0.750 0.871 1.000 1.107 1.320 1.500 1.890 157.1 F 0.299 0.357 0.440 0.510 0.598 0.719 0.840 0.987 1.114 1.210 1.335 1.465 1.685 2.100 227.7 F 0.338 0.408 0.492 0.571 0.671 0.813 0.953 1.107 1.235 1.361 1.495 1.670 1.890 2.373 267 9 F 0.355 0.418 0.523 0.598 0.710 0.851 1.008 1.165 1.307 1.456 1.488 1.755 1.942 2.510 686 CHAPTER 40. PIPE AND DUCT INSULATION multiplied to obtain the free convective transfer from various shapes whose characteristic dimensions are 24 in. or over, and Table 5 gives the factors to be used in conjunction with the factors in Table 4 for obtaining the free convection from Table 3 for pipes and ducts whose characteristic dimensions are less than 24 in. Table 8. Heat Loss from Bright Copper Pipe Given One Thin Coat of Clear Lacquer Expressed in Btu per hour per linear foot per degree Fahrenheit between the pipe and surrounding still air at 70 F Nominal (Inches) )4 M l 1)4 1)4 2 2)4 3 2% 4 4)4 5 6 8 . Hoi Water (Type K Copper Tube) Steam (Standard Pipe Size Pipe) 120 F 150 F 180 F I 227.1 F (S Lb) 297.7 F (50 Lb) 337.9 F (100 Lb) Temperature Difference SO F 0.240 0.320 0.390 0.470 0.540 0.690 0.840 0.960 1.100 1.241 1.480 1.700 2.200 80 F 0.265 0.356 0.437 0.537 0.612 0.762 0.937 1.025 1.250 1.400 1.685 1.936 2.500 110 F 0.282 0.373 0.463 0.554 0.645 0.818 0.991 1.135 1.318 1.480 1.790 2.052 2.630 140 F 0.307 0.414 0.507 0.614 0.714 0.892 1.085 1.270 1.442 1.556 1.965 2.272 2.854 1 157.1 F 0.401 0.477 0.598 0.700 1.208 1.005 1.178 1.400 1.580 1.750 1.910 2.130 2.450 3.120 227.7 F 0.461 0.571 0.681 0.812 0.966 1.164 1.361 1.625 1.845 2.040 2.240 2.415 2.810 3.425 267.9 F 0.478 0.578 0.710 0.840 0.990 1.201 1.420 1.700 1.905 2.130 2.350 2.610 2.990 3.730 Table 9. Heat Loss from Horizontal Tarnished Copper Pipe Expressed in Btu per hour per linear foot per degree Fahrenheit between the pipe and surrounding still air at 70 F Nominal Pips Size (Inches) Hot Water (Type K Copper Tube) Steam (Standard Pipe Size Pipe) 120 F 150 F 180 F 210 F 227.1 F (5 Lb) 297.7 F (50 Lb) 337.9 F (100 Lb) Temperature Difference 50 F 80 F 110 F 140 F 157.1 F ` 227.7 F 267.9 F y-i 0.250 0.287 0.300 0.321 0.433 0.500 0.530 M 0.340 0.381 0.409 0.429 0.533 0.543 0.654 i 0.440 0.475 0.509 0.536 0.636 0.746 0.803 m 0.500 0.559 0.618 0.622 0.764 0.878 0.934 i)4 0.580 0.656 0.710 0.750 0.904 1.053 1.120 2 0.730 0.825 0.890 0.957 1.101 1.273 1.364 2)4 0.880 1.000 1.091 1.143 1.305 1.490 1.605 3 1.040 1.175 1.272 1.343 1.560 1.800 1.940 3)4 4 1.180 1.460 1.350 1.500 1.454 1.635 1.535 1.715 1.750 1.941 2.020 2.240 2.170 2.430 4)4 2.131 2.465 2.650 5 1.600 1.812 1.980 2.071 2.387 2.770 2.990 6 1.840 2.125 2.270 2.430 2.740 3.210 3.440 8 2.400 2.685 2.910 3.110 3.310 4.050 4.370 687 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 10. Radiating Surface per Linear Foot of Pipe Nominal Pipe Sict (Inches) H H l m ,,. Surface Abba (Sq Ft) R H Nominal She (Inches) 0.22 12 0.275 0.344 0.435 0.498 2A 3 1 3A j4 n. Sdotict Aeei (Sq Ft) 1 Nominal I PlpE SnB | (Inches) 0.622 0.753 0.917 1.047 1.178 S I j 5 6 8 10 12 Surtace Area (Sq Ft) 1.456 1.734 2.257 2.817 3.338 Table 1. 1 Radiating Surface per Linear Foot of Copper Tubing Outside diameter 54 in. greater than nominal size Tube Sm (Inches) a 54 1 m iA Scbta.ce Abba (Sq Ft) B j Tube Size (Inches) 0.164 0.229 0.295 0.360 0.426 2 1 2H 3 | 3A j4 Surface Area H (Sq Ft) | Tube Sum (Inches) 0.556 0.687 0.818 0.949 1.080 | | I 5 6 8 Surface Area (Sq Ft) 1.342 1.604 2.128 1 For example, the free convection transfer from a 3 in. o.d. horizontal cylinder for a temperature difference of 40 F = 25.0 X 0.73 X 1.52 = 27.7 Btu per square foot per hour. The increased rate of heat transfer due to forced convection can be calculated from the formula: 2fc = 1 + 0.225 V (3) where if = heat transfer by forced convection, Btu per square foot per hour per degree Fahrenheit temperature difference. V = velocity of air, feet per second. This formula is approximately correct for large surfaces exposed to air currents at temperatures of approximately 70 to 80 F. HEAT LOSSES FROM BARE PIPES Heat losses from horizontal bare-steel pipes, based on tests conducted at Mellon Institute and calculated from Equations 1 and 2 are given in Table 6. The monetary values of the loss of heat given in Table 6 may be obtained by means of Fig. 1 for various heating system efficiencies, temperature differences, and calorific values, and costs of coal. To solve a problem, select the proper heat loss coefficient from Table 6 and locate this value on the upper left-hand margin of the chart. Then draw lines in the order indicated by the dotted lines, the dollar value of the heat loss per 100 linear feet of pipe per 1000 hours being given on the upper right-hand scale. In using the chart, the cost of coal should also include the labor for handling it, boiler room expense, etc. Heat losses from horizontal copper tubes and pipes with bright, lacquered and tarnished surfaces are given in Tables 7, 8, and 9s. Heat Loss from Copper Piping, by R. H. Heilman (Healing, Piping and Air Conditioning, September. 1933, p. 458). 688 J| . -v-- -! > CHAPTER 40. PIPE AND DUCT INSULATION D O L L A R S VALUE-HEAT LOSS PER 1000MP5 PER 100t lN T T Fig. 1. Chart for Estimating Dollar Value of Heat Loss from Bare Iron Pipes. (See Table 6)a This chart is based on 100 linear feet per 1000 hours. For fractions or multiples of these factors, multiply by proper percentage. The area in square feet per linear foot of pipe is given in Table 10 for various standard pipe sizes, and Table 11 for copper tubing, while Table 12 gives the area in square feet of flanges and fittings for various standard pipe sizes. These tables can be used to advantage in estimating the amount of insulating cement required for various equipment. Very often, when pipes are insulated, flanges and fittings are left bare so as to allow for easy access to the fittings in case of repairs. The fact that a pair of 8-in. standard flanges having an area of 2.41 sq ft would lose, at 100 lb steam pressure, an amount of heat equivalent to more than a ton of coal per year shows the necessity for insulating such surfaces. 689 , . ; j B.T.U. PER UNEAR FOOT PER HOUR PER DEG FAHR TEMPERATURE DIFFERENCE HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Fig. 2. Heat Loss Through 1 In. Thick 85 per cent Magnesia Type Covering 690 CHAPTER 40. PIPE AND DUCT INSULATION Table 12. Areas of Flanged Fittings, Square Feet* Nominal Pips Sicb (Inches) i IX FX 2 3 4 4H .5 6 8 10 12 FLajtOED Coupling 90 Deo Ell LongRtR.i-adius Tbs Cross Standarc Extra Heavy Standan Extra Heavy Standan Extra Heavy Standard Extra Heavy Standard Extra Heavy 0.320 0.383 0.477 0.672 0.841 0.945 1.122 1.344 1.474 1.622 1.82 2.41 3.43 4.41 0.438 0.510 0.727 0.848 1.107 1.484 0.795 0.957 1.174 1.65 2.09 2.38 1.015 1.098 1.332 2.01 2.57 3.49 0.892 1.084 1.337 1.84 2.32 2.68 1.083 1.340 1.874 2.16 2.76 3.74 1.235 1.481 1.815 2.54 3.21 3.66 1.575 1.925 2.68 3.09 4.05 5.33 1.622 1.943 2.38 3.32 4.19 4.77 2.07 2.53 3.54 4.06 5 17 6 95 1.644 2.98 1.914 3.53 2.04 3.95 2.18 4.44 2.78 5.13 3.77 6.98 5.20 10.18 6.71 13.08 3.96 4.64 5.02 5.47 6.99 9.76 13.58 17.73 3.28 3.96 4.43 5.00 5.99 8.56 12.35 16.35 4.28 4.99 5.46 6.02 7.76 11.09 15.60 18.76 4.48 5.41 6.07 6.81 7.84 10.55 15.41 19.67 6.04 7.07 7.72 8.52 10.64 14.74 20.41 26.65 5.83 7.03 7.87 8.82 10.08 13.44 19.58 24.87 7.89 9 24 1007 10.97 13.75 18.97 26.26 34.11 `Including areas of accompanying Ranges bolted to the fitting. .. ------ rnwv ,,..w ixsiw* oiiuudi uc<tL auss ironi ivo it ot z m. Dare pipe in service 4000 hr per year. The pipe is carrying steam at 10 lb pressure and is exposed to an average air temperature of 70 F. Solution. The pipe temperature is taken as the steam temperature, which is 239.4 t , obtained by interpolation from Table 8 Chapter 1. The temperature difference between the pipe and air = 239.4 -- 70 = 169.4 F. By interpolation of Table 6 between tem perature differences of 157.1 and 227.7 F, the heat loss from a 2 in. pipe at a temperature difference of 169.4 F is found to be 1.624 Btu per hour per linear foot per degree tem perature difference. The total annual heat loss from the entire line = 1.624 X 169-4 X 165 (linear feet) X 4000 (hr) = 181,600 Mb. Example 2. Coal costing $11.50 per ton and having a calorific value of 13,000 Btu per pound is being burned in the furnace supplying steam to tke pipe line given in the previous example- If the system is operating at an overall efficiency of 55 per cent, determine the monetary value of the annual heat loss from the line. Solution. The cost of heat per 1000 Mb supplied to the system == 1,000,000 X 11.5 Table 13. Conductivity (k) of Various Tyres of Insulating Materials for Medium and High Temperature Pipes3 Types of insulating Materials 85 per cent Magnesia Type..... Corrugated Asbestos Type... . (4 Plies per 1 in. thick) Corrugated Asbestos Type. (8 Plies per 1 in. thick) Laminated Asbestos Type........ (30-40 Laminations per 1 in. thick) Laminated Asbestos Type (14-20 Laminations per 1 in. thick) Mineral Wool TvDe. High Temperature Tvoe. (Diatomaceous Earth and Asbestos) Brown Asbestos Tvpe (Felted Fiber) Mean Temperature. Dec F 100 0.359 0,495 0.505 0.326 0.374 0.350 0.576 0.338 200 0.403 0.618 0.598 0.380 0.445 0.410 0.614 0.396 300 0.448 0.741 0.692 0.434 0.518 0.470 0.652 0.453 400 0.493 0.864 0.786 0.488 0.589 0.530 0.689 0.510 500 0.539 ___ 0.543 0.662 0.590 0.726 0.568 From tests conducted at Mellon Institute. 691 HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 (dollars) -* 13,000 (Btu) X 2000 (lb) X 0.55 (efficiency) = 30.804. The total cost of heat lost per year = 0.804 X 181.6 (thousand Btu) = $146.00. (A closely approximate solution of such problem may be made quickly by the use of the estimating chart given in Fig. 1.) HEAT LOSSES FROM INSULATED PIPES The conductivities of various materials used for insulating steam and hot water systems are given in Table 13. They are given as functions of ' CHAPTER 40. PIPE AND DUCT INSULATION typie of insulation for temperature differences between the pipie and the surrounding atmosphere up to 280 F are shown in Figs. 2, 3, and 4. Standard thicknesses of 85 per cent Magnesia pipe covering are not exactly 1 in. However, the loss through any given thickness of insulation can be obtained by interpolation. Also, the losses through any of the insulations, given in Table 13 can be obtained by multiplying the losses obtained from Figs. 2, 3, or 4 by the factors given in Table 14. The rate of heat loss from a surface maintained at constant tempierature is greatly increased by air circulation over the surface. In the case of Fig. 3. Heat Loss Through 1)4 In- Thick 85 per cent Magnesia Type Covering the mean temperatures or the mean of the inner and outer surface tem peratures of the insulations. It should be emphasized that they are the average values obtained from a number of tests made on each type of material, also that all variables due to differences in thickness, pipe sizes, and air conditions are eliminated. Individual manufacturer's materials will, of course, vary in conductivity to some extent from these values. The heat losses through 1, 1^4, and 2-in. thick 85 pier cent Magnesia 692 _____ _____ *.ww fc-TV CPU . " TEMPERATURE DIFFERENCE FROM PIPE TO ROOM, DEG FAHR Fig. 4. Heat Loss Through 2 In. Thick 85 per cent Magnesia Type Covering well-insulated surfaces, the increases in losses due to air velocity are very small as compared with increases from bare surfaces, which is indicated by Equation 3, because of the fact that air flowing over the surface of the insulation can increase only the rate of heat transfer from surface to air, and cannot change the internal resistance to heat flow inherent in the insulation itself. The maximum increase in heat loss due to air velocity ranges from about 30 per cent in the case of 1-in. thick insulation, to about 10 per cent in the case of 3-in. thick insulation, provided that the: insu lation is thoroughly sealed so that air can flow only over the surface. 693 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 If the conditions are such that the air may circulate through cracks and crevices in the insulation, the increases may be far greater than those given. Therefore, it is essential that insulation be sealed as tightly'as possible. Pipe insulation exposed to the elements should be thoroughly waterproofed. Example 3. If the steam line given in Examples X and 2 is covered with 1 in. thick 85 per cent magnesia, determine the resulting total annual loss through the insulation. Also compute the monetary value of the annual saving and the percentage of saving over the heat loss from the bare pipe. . Solution. By referring to Fig. 2, the coefficient for 1 in. magnesia on a 2 in. pipe is found to be 0.285 Btu per hour per linear foot of pipe per degree temperature difference at a temperature difference of 169.4 F. The total hourly loss per linear foot of pipe will then be 0.285 X 169.4 = 48.3 Btu. The total annual loss through the insulation -- 48.3 X 165 (linear feet) X 4000 (hr) ** 31,900 Mb. The annual bare pipe loss as determined in the solution of Example 1 was found to be 181,600 Mb. The saving due to insulation is then 181,600 -- 31,900 ~ 149,700 Mb per year. From the solution of Example 2, it was found that the heat supplied to the system cost $0,804 per thousand Mb. Therefore, the monetary value of the saving = 0.804 (dollars) X 149.7 (thousand Mb) -- $120.36, or 82.4 per cent of the cost when using uninsulated pipe. . Table 14. Pipe Covering Factors FTemperature Difference. Pipe to Air, Dbg 100 200 300 (4 Plies per X in. thick) (8 Plies per 1 in. thick) (30-40 Laminations per 1 in. thick) (14-20 Laminations per 1 in. thick) (Diatomaceous Earth and Asbestos) (Felted Fiber) 1.050 1.425 1.435 0.969 1.103 1.023 1.560 1.003 1.024 1.465 1.437 0.960 1.104 1.028 1.489 0.997 0.997 1.505 1.438 0.951 1.105 1.033 1.418 0.990 400 0.971 1.545 1.440 0.942 1.106 1.038 1.347 0.984 500 _0._9_44 0.933 1.107 1.043 1.276 0.977 600 _0._918 0.924 1.108 1.048 1.205 0.971 HEAT LOSSES FROM DUCTS The thermal transmission coefficient U for an uninsulated metal duct can be obtained from the equation: . ___ t V= l + (4) where U = thermal transmittance, Btu per square foot per hour per degree Fahrenheit difference in temperature between the average temperature inside the duct and the air outside the duct. fi = film conductance inside the duct, Btu per hour per square foot per degree Fahrenheit. fo = film conductance outside the duct, Btu per hour per square foot per degree Fahrenheit. . 694 SW8W*-****"' CHAPTER 40. PIPE AND DUCT INSULATION Film conductance/i for air flowing in ducts apparently depends only on the velocity of the air and the diameter of the duct. A fairly reliable inside coefficient can be calculated from Schultz's modified equation: 0.32 Fo0-* . ... . f1---------/joli W where Vo -- velocity of air in duct, feet per second. D -- diameter of duct, feet. Film conductance f0 depends on a number of variables including tem perature, diameter, and emissivity of the outer surface. Conductance fQ can be readily calculated from Tables 1, 2, 3, 4, and 5. From this ex planation, it is seen that it is unwise to recommend a given value of U for all uninsulated metal ducts. The heat loss from a given length of duct can be expressed by: 0= (6) The heat given up by the air in the duct is: Q = 0.24 M (h - h) = 14.4 A Vd (h - h) (7) Equating 6 and 7 enables the determination of the temperature drop in the duct: h + h - 21, = 28.8 A Vd ti -- ti UPL y ,, 28.8 AVd, ,, , , . 7.2 DVd , , , . ,. , Let x = --IJpL-- or rectangular ducts, = ---- for round ducts, solving for h and fe: . , _ h (x + 1) - 21, ' fi-- 1) T (8) = h (*-!)+ 21, *+1 (9) For low velocities and long ducts of small cross-section, a somewhat more accurate formula may be used as follows: h = (-UPL \ + h :\14.4 AdV) (10) In these equations Q = heat loss through duct walls, Btu per hour. : V = thermal transmission coefficient, Btu per square foot per hour per degree Fahrenheit. P ** perimeter of duct, feet. L -- length of duct, feet. ' . h -- temperature of air entering duct, degree Fahrenheit. h = temperature of air leaving duct, degree Fahrenheit. ti = temperature of air surrounding duct, degree Fahrenheit. M = weight of air per hour, through the duct, pounds. ' A cross-sectional area of duct, feet. 695 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 D -- diameter of round ducts, feet. V = velocity of air in the duct, feet per minute, at specified temperature. d = density of air, pounds per cubic foot, at the specified temperature at which V is measured. e = naperian base of logarithms = 2.718. . In using formulae 8, 9, and 10, one of the duct air temperatures will be unknown and will be solved for by substitution of the other known or assumed values. The assumed values dependent upon the mean duct air temperature can be determined exactly by the.cut-and-try method. Table 15 Heat Transmission Through Duct Walls Insulated with Materials l able id. QF varying Conductivities3 Values are expressed in Btu per hour per square foot of flat surface per degree^Fahrenheit difference in temnppeerraatiuurrec bucentwuceceTnt air inside and stilll <air outside at 90 F for * cold ra,;i*r /avnrtAd F6i0n F ffoor warm aavtr tn ducts __________ Conductivity or lnSUUTIOD AT 86 F Meab Temp 0.200 0.250 0.300 0.350 0.450 0.550 Insulation (Inches) Yi 1 iH 2 Y 1 \y 2 1 1Y 2 Y l 1Y 2 Y 1 1Y 2 Ye 1 1Y 2' Cou> Ala 40 F 60 F 80 F 90F 120 F 150 F ISO F Tempebatoeb Dutfeeescb 50 F 0.319 0.175 0.121 0.092 0.382 0.214 0.149 0.114 0.440 0.252 0.176 0.135 0.494 0.286 0.202 0.156 30 F 0.323 0.177 0.122 0.093 0.387 0.217 0.151 0.115 0.445 0.255 0.178 0.137 0.499 0.289 0.204 0.158 0.596 0.356 0.254 0.198 0.682 0.417 0.302 0.236 10 F 0.328 0.180 0.124 0.095. 0.392 0.220 0.153 0.117 0.450 0.258 0.180 0.139 0.505 0.292 0.207 0.160 0.602 0.360 0.257 0.200 0.688 0.422 0.305 0.239 40 F 70 F 0.324 I 0.330 0.178 0.181 0.125 0.390 0.218 0.397 0.221 0.154 0.448 0.256 0.457 0.260 0.181 0.502 0.511 0.290 0.295 0.208 0.599 0.358 0.610 0.364 0.259 0.685 I 0.699 0.418 0.425 0.307 100 F 0.337 0.184 0.127 0.404 0.225 0.156 0.466 0.264 0.184 0.521 0.300 0.211 0.621 0.370 0.263 0.714 0.432 0.312 130 F 0.344 0.188 0.129 0.412 0.229 0.159 0.475 0.268 0.187 0.530 0.306 0.215 0.633 0.376 0.267 0.730 0.440 0.317 .For round ducts less than 30 iu. diameter, increase heat transmission values by the following oercent- ages: Thickness of Insulation (laches) ------*------ ;--~ ___ \ 12 to 21 in. Duct Diameter--,,---------------- -------------------- -------- - - 3% 1 1% 5% 1M 7$ CHAPTER 40. PIPE AND DUCT INSULATION - Heat losses for insulated ducts are given in the warm air column of . Table 15. The losses are based on a uniform series of material con ductivities at 86 F mean temperature and an air temperature of 50 F Outside of the duct. The losses may be interpolated for odd material conductivities and temperatures. The conductivities of various materials will be found in Table 2 of Chapter 5. For cases where the surrounding air temperature is other than 50 F, the losses may be selected on the basis of temperature difference. . ' Recently, a new prefabricated insulated duct built entirely of asbestos has been placed on the market. - Example 4- Determine the entering air temperature and heat loss for a duct 24 X 36 in. cross-section and 70 ft in length, insulated with % in. of a material having a con ductivity of 0.35 Btu at-86 F mean temperature, carrying air at a velocity of 1200 fpm, measured at 70 F, .to deliver air at 120 F with air surrounding the duct at 40 F. . Solution. Assume the entering air temperature to be 130 F. Thus, the mean tem perature difference will be 85 F. Referring to the warm air column of Table 15 and interpolating for .85 F temperature difference, the overall heat transmission coefficient is found to be 0.516 Btu. From Table 4 Chapter 1 the density of air at 70 F and.29.92 in. Hg. is found to be 0.07423 lb per cubic foot. Substituting these and the other given values in Formula 8: .. * 28.8 X 6 X 0.07423-X 1200 = '42.61 0.516 X 10 X 70 . ,. . . , 120 (42.61 + 1) - 80 , h = ------- 42l;r-~l--~ = 123 6 . : Based on 123.8 F entering air temperature, the new mean temperature difference will' be 81.9 F arid the new transmission coefficient will be 0.515. Resubstituting in Formula1 8, t\ becomes 123.9 F. l. . :. Substituting in formula 6: Q = 0.515 X 10 X 70 ^123'9-2+-120^ _ 40 J Q = 29.543 Btu LOW TEMPERATURE INSULATION Surfaces maintained at temperatures lower than, the surrounding air are insulated to reduce the flow of heat and to prevent condensation and frost. The insulating material should absorb a minimum amiount of moisture, for. one. reason'that the absorption of moisture substantially increases the Conductivity of the material. ; This property is particularly important in the case of surfaces to be: insulated that are below the dew point of the; surrounding air. In such cases, due to! vapor pressure difference, it ; is necessary to seal the surface of the insulating material against the penetration of water vapor which would condensef within the material, causing a serious increase in heat flow, possible breakdown of the material'and corrosion of metal surfaces. An insulating material with a high degree of moisture absorption might pick up moisture before application and then, when the seal is in place and the temperature of the insulated surface reduced, release that moisture to the cold surface. The thickness. ;of insulation required to prevent sweating. is that thickness which will raise the temperature of the outer surface of the 697 . -1I HEATINC VENTILATING AIR CONDITIONING- GUIDE 1940 insulation to a point slightly higher than the dew-point for the corre sponding air temperature and relative humidity. The difference in tem perature between the air and the dew-point for various humidities can be readily, ascertained from a psychrometric chart. The thickness of insulation required to prevent sweating for rectangular ducts will be slightly greater than the value obtained by solving the equation: `-[HMW)] (11) where . L = thickness of insulation for flat surfaces, inches. . * Ti = temperature of air in room, degrees Fahrenheit. Tt = temperature of surface of insulation, degrees Fahrenheit. T> = average temperature of cooler air in duct, degrees Fahrenheit. k = conductivity of insulation, Btu per hour per square foot per degree Fahrenheit per inch. ; g = heat loss per square foot of outer surface of insulation, Btu per hour. ' fa and f\ have the same values as given in Formula 4. In any practical case Ti and Tz will be known, and, for any assumed value of relative humidity (7\ -- Tt) can be obtained from a psychro metric chart. Values of q and/0 can be obtained from Tables 1, 2, 3, and 4; /i from Formula 5; and k from conductivity Table 2 of Chapter 5. The approximate thickness of insulation used to prevent condensation on pipes and flat metallic surfaces may be obtained from Fig. 5. The maximum permissible temperature drop is indicated at the point where the guide line passes through the horizontal scale at the left center of the Table 16. Heat Gains for Insulated Cold Pipes Rates of heat transmission given in Btu per hour per degree Fahrenheit temperature difference between fluid in pipe and surrounding still air Based on materials having conductivity, k = O.SO - Kominai. Pips 8na (Inches) a H 1 m m 2 Wl 3 3K 4 5 6 8 10 12 Ice Water Thickness Thickness of Insulation (Inches) 1.5 1.6 1.6 1.6 1.5 1.5 1.5 1.5 1.5 1.7 1.7 1.7 1.9 1.9 1.9 Btu Per Linear . Foot Btu Per Sq Ft ripe Surface 0.110 0.119 0.139 0:155 0.174 0.200 0.228 0.269 0.295 0.294 0.349 0.404 0.455 0.559 0.648 0.502 0.431 0.403 0.357 0.351 0.322 0.303 0.293 0.282 0.248 0.239 0.233 0.201 0.198 0.194 Brine Thickness Thickness of Insulation (Inches) 2.0 2.0 2.0 2.4 2.5 2.5 2.6 2.7 2.9 2.9 3.0 3.0 3.0 3.0 3.0 Btu Per linear Foot Btu Per Sq Ft Pipe Surface 0.098 0.111 0.124 0.131 0.134 0.151 0.170 0.186 0.191 0.209 0.241 0.259 0.318 0.383 0.438 0.446 0.405 0.352 0.300 0.270 0.244 0.226 0.202 0.183 0.176 0.165 0.150 0.140 0.135 0.131 Heavt Brine Thickness Thickness of ' Insulation (Inches) 2.8 2.9 3.0 3.1 3.2 3.3 3.3 3.4 3.5 3.7 3.9 4.0 4.0 4.0 4.0 Btu Per linear Foot Btu Per Sq Ft Pipe . Surface 0.087 0.394 0.094 0.340 0.104 0.294 0.113 0.260 0.118 0.238 0.134 0.214 0.147 0.197 0.162 0.176 0.176 0.167 0.182 0:154 0.202 0.138 0.228 0.130 0.263 0.116 0.309 0.110 0.364 0.108 698 CHAPTER 40. PIPE AND DUCT INSULATION chart. This temperature drop represents the difference between the drybulb temperature and the dew-point temperature for the conditions involved. (See discussion of Condensation in Chapter 5.) The surface resistances used for calculating the family of curves in Fig.. 5 are based on tests made on canvas covered pipe insulation surfaces at Mellon Institute. However, it has been found that the resistance for asphaltic and roofing Fig. 5. Thickness of Pipe Insulation to Prevent Sweating3 "Solve problems by drawing lines as indicated by dotted line, entering chart at lower left hand scale. surfaces is practically the same as for canvas surfaces, so that the curves may be followed with no alteration for surfaces commonly used. Heat gains for pipes insulated with a material having a conductivity of 0.30 Btu per square foot per hour per degree Fahrenheit difference per inch thickness are given in Table 16. Heat gains for insulated ducts are given in the cold air column of Table 15. The heat gains are based on a uniform series of conductivities at 86 F mean temperature and an air temperature of 90 F outside of the duct. The gains may be interpolated for odd material conductivities and 699 HEATING VENTILATING AIR CONDITIONING' GUIDE 1940 -temperatures. For cases where the surrounding air temperature is. other than 90 F the gain's may be selected on the basis of temperature difference. i INSULATION OF PIPES TO PREVENT FREEZING ' If the surrounding air temperature remains sufficiently low for an ample period' of time, insulation' cannot prevent the freezing of still water, or of water flowing at such a velocity that the quantity of heat carried in the water is not sufficient to take care of the heatlosses which will result and cause the temperature of the water, to be lowered to the freezing point. Insulation can materially prolong the time required for the water to give up its heat, and if the velocity of the water flowing in the pipe is main tained at a sufficiently high rate, freezing may be prevented. Table 17 may be used for making estimates of the thickness of insu lation necessary to take care of still water in pipes at various water and surrounding air temperature conditions. Because of the damage and service interruptions which may result from frozen water in pipes, it is essential that an efficient insulation be utilized. This table is based on the use of a material having a conductivity of 0.30. The initial water temperature is assumed to be 10 F above, and the surrounding air tem perature 50 F below the freezing point of water (temperature difference, 60 F). The last column of Table 17 gives the minimum quantity of water at initial temperature of 42 F which should be supplied every hour for each linear foot of pipe, in order to prevent the temperature of the water from being lowered to the freezing point. The weights given in this column should be multiplied by the total length of the exposed pipe line expressed in feet. As an additional factor of safety, and in order to provide against temporary reductions in flow occasioned by reduced'pressure, it is ad visable to double the rates of flow listed in the table. It must be empha sized that the flow rates and periods of time designated apply only for the conditions stated. To estimate for other service conditions the following method of procedure may be used. ' If water enters the pipe at 52 F instead of 42 F, the time required to cool it to the freezing point will be prolonged to twice that given in the table, or the rate of flow of water may be reduced so that the quantity required will, be one-half that shown in the last column of Table 17: However, if the water enters the pipe at 34 F it will be cooled to 32 F in one-fifth of the time given in the table. It will then be necessary to increase the rate of flow so that five times the specified quantity of water will have to be supplied in order to prevent freezing. . '. If the minimum air temperature is -- 38 F (temperature difference 80 F) instead of --18 F, the time required to cool the water to the freezing point will be 60/80 of the time given in the table, or the necessary quantity of wate'r to be supplied will be 80/60 of that given. - In making calculations to arrive at the values given in Table 17, the loss of heat stored in the insulation, the effect of a varying temperature difference due to the codling of pipe and water, and the resistance of the outer surface of the insulation to the transfer of heat to the air have all been neglected. When these factors enter into the computations it is necessary to enlarge the factor of safety. Also as stated, the time shown 700 ' CHAPTER 40. PIPE AND DUCT INSULATION ...--- --. run CLIMATING KEQUIREMENTS TO Prfvfvt Freezing of Water in Pipes with Surrounding Airat -- 18 F Nominal! : Pipe (Inches)I Number of Hours to Cool 42 F Water to Fremwq Point .- : R^omKD AT F to Prevent freezing. Pounds per Linear Foot " I ; op Pipe per Hour - ` 1 H1 1I .2.1. 3| 41 51 61 8 1. 10 I 12 .j 2' 0.42 0.83 1.40 1.94 3.25 4.55 5.92 7.35 10.05 13.00 15.80 Thickness of Insulation in. inches `(Conductmty, k 0J0) v; 3 : :4 ; - . y i . 0.50 1.02 1.74 . 2.48 4.27. 6.02 7:96 . "'9:88 13.90 ; 18.10 22.20 0.57 .0.54 ' 6.45 1.16 0.68 2.02 - 0.84 2.90 . ' 0.95 5.08 1.24 7.20 , 1-47 9.69 1.73 . 12.20 ' 1.98 17.25 1 2.46 ' i- 22.70 1 1 2.96 28.10 ' ' 1 3.43 0.55:". 0.68 . 0.75 0.94 1.11 1.29 1.46 1.78 : 2.12 2.45 4 0.40 0.48 0.58 0.64 0.79 0.93 1.06: 1.19: 1.43 1.70 1.93 ; ; : : ; : . . . -- -- ' : y ' in the table is that required to lower the water to the freezing point. A- longer period would be required to freeze the water but the danger point is reached when freezing starts: The flow, of water will stop and the entire line will be in danger as soon as the water freezes across the section of the- pipe at any point. . When water must remain stationary longer than the times.designated in Table 17, the only safe way to insure against freezing is to install a' steam or hot water line or to place an electric resistance heater along the:side of the exposed water line. The heating system and the water line-are then insulated so that the heat losses from the heating system are not excessive, and the heating effect is concentrated against the water pipe where it is needed. For this form of protection 2 in. of an efficient insu-. lation may be applied. '' . _______ _ - , .. nwVUM IVM _ The thicknesses of. insulation which ordinarily are used for various- temperature conditions are given in Table 18. Where a thorough analysis, Table 18. Thicknesses or Insulation Ordinarily used Indoors3 Steam Pressure (1* Gass) . or Conditions . '.. : Steam Temperatures / Fahrenheit 0 to 25 25 to 100 ' 100 to 200 Low Superheat Medium Superheat High Superheat 212 to 267 267 to 338 338 to 388 388 to 500 500 to 600 600 to 700 . Thickness of Insulation Pjpw Larger loan 4 Id. 1 in. in. . 2 in. 2 in. 3 in. in. Pipes 2 In. to 4 In. 1 in. 1 in. in. 2 in. in. 3 in; Pipes HIo. 1 in. 1 in. 1 in. IHin. 2 in. 2 in. : ;70I ucA-rmr. VENTILATING AIR CONDITIONING CU1DE WO Fig. 6. Chart for Determining Economical Thickness of Insolation CHAPTER 40. PIPE AND DUCT INSULATION of economic thickness is desired this may be accomplished through the the use of the chart, Fig. 6. The dotted line on the chart illustrates its use in solving a typical example. In using the chart, start with the scale at the left bottom margin representing the given number of hours of operation per year; then proceed vertically to the line representing the given value of heat; thence horizontally to the right, to the line representing the given tem perature difference; thence vertically to the line representing the con ductivity of the given material; thence horizontally, to the left, to the line representing the given discount on that material; thence vertically to the,curve representing the required per cent return on the investment; thence horizontally to the right, to the curve representing the given pipe size; thence vertically to the scale at the top right margin where the economical thickness may be read off directly. UNDERGROUND PIPE INSULATION Underground steam distribution lines are carried in protective struc tures of various types, sizes and shapes. (See Chapter 43). Detailed data on commonly used forms of tunnels and conduit systems have been published by the National District Healing Association4. Pipes in tunnels are covered with .sectional insulation to provide maximum thermal efficiency and are also finished with good mechanical protection in the form of metal or waterproofing membrane outer jackets. Conduit systems are in more general use than tunnels. Pipes carried in conduits may be insulated with sectional insulation; however, the more usual practice is to fill the entire section of the conduit around the pipes with high quality, loose insulating material. The insulation must be kept dry at all times, and for this purpose effective waterproofing mem branes enclose the insulation. A drainage system is also provided to divert water which may tend to enter the conduit. The economical thickness of insulation for underground work is difficult to determine accurately due to the many variables which have to be considered. As a result of theories6 previously developed, together with Table 19. Thickness op Loose Insulation for Use as Fill in Underground Conduit Systems Steam Pressures (Lb Gage) ob Conditions Steam Temperatures Degrees Fahrenheit Minimum Thickness op Insulation m Inches Steam Lines Return Lines Pipes Less Pipes 4 In. Pipes Larger Pipes Less Pipes 4 In. than 4 In. to 10 In. than 12 In. than 4 In. and Larger Minimum Distance Between AND Return Hot Water, or 0 to 25 212 to 267 IK 2 2K m lM i 25 to 125 267 to 352 Above 125, or 2 2H 3 IK IK IK superheat 352 to 500 2 K 3 3K IK l K IK `Handbook of the National District Heating Association, Second Edition, 1932. `Theory of Heat Losses from Pipes Buried in the Ground, by J. R. Alien (A.S.H.V.E. Transactions, Vol. 26. 1920, p. 335). 703 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 other experimental-data which have.been.presented, the usual endeavor is to secure not less than 90 per cent efficiency for. underground piping. Table 19 can be used as,a guide in arriving at the minimum thickness-of loose insulation :fills to use for laying out conduit systems. Other factors such as the nuniber.of pipes and their combination of sizes, as well as the standard conduit sizes, are primary controlling factors in the amount and thickness of insulation for use. . ; ' . .:' . ..When sectional insulation is applied to lines in tunnels or:.conduits, usual,practicejs to apply the most efficient materials in. less in thick ness than that determined by the use of Fig: 6. The data in Fig. 6 are based on conditions of insulation exposed to the air,, whereas normal ground temperature is substituted- for air temperature in determining the tem perature difference for use with the chart when applying it for under ground pipe line estimates. . - ... .. Chapter 41 ELECTRICAL HEATING Resistors, Heating Elements, Electric Heaters, Unit Heaters, Central Fan Heating, Electric Steam Heating, Electric Hot Water Heating, Heating Domestic Water Supply, Industrial Heating, Reversed Cycle Refrigeration, Auxiliary Electric Heating, Control, Calculating Capacities, Power Problems, Insulation ELECTRIC heating is steadily assuming a more important place in heating, ventilating and air conditioning installations, accelerated in many territories by the load building efforts of the utilities which usually include reduced rates to encourage such installations. Electrical heating has a logical place in the heating industry because of its features of flexibility, cleanliness, safety, convenience and ease of control. Electrical heating practice has many basic principles in common with fuel heating, but there are also important differences. When heat units are delivered to each room by wire, no combustion process is necessary, either at a central plant or at the individual room units. The maximum output of an electric heater is a fixed constant, unaffected by the temperature of the' surrounding air and it follows that the maximum total load on an electrical heating system is the total wattage of connected electric heaters, regard less of weather conditions. The real obstacle to the more general adoption of electric heating for buildings is the cost of the electricity itself. Because the heat' units produced.electrically are more costly, their conservation is of more; relative economic importance than with fueL heating, so that sponsors of electric heating give greater attention to temperature-insu-; lated building construction, and to economy by accurate controls. ; - .; -'* All heat.is a form of energy. Fuels hold stored-chemical energy which1 is released into heat by combustion. Electrical power is a form of energy which can be released into heat by passing it through a resisting material. Both fuel and electric heating have two divisions; first, the conversion .of energy into heat; second, the distribution and practical use of the heat after it is produced. ' . 1 . ; In converting the chemical'energy of fuels into heat by combustion, there is necessarily a considerable variation in thermal efficiency. This' is-not true, however, when converting electric power into heat, because 100 per cent of the energy applied in the resistor is always transformed; into heat. In electric heating practice the engineer need not be concerned; about efficiencies of heat production, but rather about efficiencies-of heat- utilization. It is the engineer's problem to distribute the. electrically produced heat units in such manner as to obtain conditions of maximum; comfort with the minimum consumption of electricity. . ; ; . ; ^ 705 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 DEFINITIONS Definitions of terms used in fuel heating are given in Chapter 46.. The following terms apply particularly to electric heating: Electric Resistor: A material used to produce heat by passing an electric current through it. Electric Heating Element: A unit assembly consisting of a resistor, insulated sup ports, and terminals for connecting the resistor to electric power. Electric Heater: A complete assembly of heating elements with their enclosure, ready for installation in service. RESISTORS AND HEATINC ELEMENTS J Solids, liquids, and gases may be used as resistors, but most com mercial electric heating elements have solid resistors, such as metal alloys, and non-metallic compounds containing carbon. In some types of electric boilers, water forms the resistor which is heated by an alternating current of electricity passing through it. One of the more common resistors is nickel-chromium wire or ribbon which, in order to avoid oxidation, contains practically no iron. Commercial electric heating elements are made in many types. Some have resistors exposed to the air being heated. The resistors may be coils of wire or metal ribbon, supported by refractory insulation, or they may be non-metallic rods, mounted on insulators. This type of element is used extensively for operation at high temperatures when radiant heat is desired, also at low temperatures for convection and fan circulation heating, especially in large installations. Some elements have metallic resistors embedded in a refractory insu lating material, encased in a protective sheath of metal. Fins or extended surfaces may be used to add heat-dissipating area. Elements are made in many forms, such as strips, rings, plates and tubes. Strip elements are used for clamping to surfaces requiring heat by conduction, and in some types of convection air heaters. Ring and plate elements are used in electric ranges, waffle irons, and in many small air heaters. Tubular elements may be immersed in liquids, cast into metal, and, when formed into coils, used in electric ranges and air heaters. Cloth fabrics woven from flexible resistor wires and asbestos thread, are used for many low temperature purposes such as heating pads and aviators' clothing. ELECTRIC HEATERS Electric heaters may be divided into three groups, conduction, radiant and convection. . Conduction electric heaters, which deliver most of their heat by actual contact with the object to be heated,, are used in such applications as aviators' clothing, hot pads, foot warmers, soil heaters, ice melters, and water heaters. Conduction heaters are useful in conserving and localizing heat delivery at definite points. They are not suitable for general air heating. Radiant electric heaters, which deliver most of their heat by radiation, have high temperature incandescent heating elements and reflectors to concentrate the heat rays in the desired directions. The immediate and 706 . CHAPTER 41. ELECTRICAL HEATINC pleasant sensation of warmth which is caused by radiant heat makes this type desirable for temporary use where the heat rays can fall directly upon the body. They are not satisfactory for general air heating, as radiant heat rays do not warm the air through which they pass. They must first be absorbed by walls, furniture, or other solid objects which then give up the heat to the air. Gravity convection electric heaters, designed to induce thermal air circu lation, deliver heat largely by convection, and should be located and used in much the same manner as steam and hot water radiators or convectors. They generally have heating elements of large area, with moderate surface temperature, enclosed to give proper stack effect to draw cold air from the .floor line. The flexibility possible with electric heating elements should discourage the use of secondary mediums for heat transfer. Water and sfeam add nothing to the efficiency of an electric heater and entail expensive construction and maintenance. UNIT HEATERS Unit electric heaters include a built-in fan unit which circulates room air over the heating elements. Heaters of this type are manufactured in many designs and sizes, and can be located in much the same manner as steam unit heaters. Electric unit heaters are used in industrial plants, sub-stations, power houses, pumping stations, etc., where the power rate for electric heating is found to be favorable. The best location for the heater depends upon local circumstances as they can be mounted either on the ceiling to direct the air downward, on the side wall about 7 ft from the floor, or near the floor line. Variations in design are necessary for different locations, but typical arrangements are indicated in Figs. 1, 2, and 3. The arrangement of the wiring circuits is very important for electric unit heaters. In principle, they are all the same and include as essential elements an automatic control panel, a thermostat, and a master hand switch. All heaters should be designed with a safety thermal trip wired in series with the magnet coil of the control panel and with the hand switch and thermostat. A typical wiring diagram is shown in Fig. 4. This applies to a single phase power supply, but for 3 phase the only difference is to have a 3-pole panel and a heater arrangement for 3-phase connection. Portable unit heaters are useful for temporary work, such as drying out damp rooms, or for warming rooms during construction. CENTRAL FAN HEATING Electric heating elements can be used for the prime source of heat in a central fan electric heating system or iri the heating phase of a complete air conditioning system. They can be used in the same manner as steam served heating units for tempering, preheating or reheating the air at the main supply fan location and as booster heaters at the delivery terminals of the duct system. In the humidification phase of air conditioning electric heating elements can be used to provide moisture by the evaporization of water, or for controlling air washer dew-point temperatures when . mounted as preheating units on the intake side of the air washer. (See Chapter 21.) 707 HEATING VENTILATING. AIR CONDITIONING: GUIDE 1940 coordinating the input of heat energy and the volume of air circuf l.ation, a basic difference between electric.heating and' steam-Keating enters into the problem. Steam is approximately a constant-temperature source of heat-for any given pressure and a'change in, air volume flowing over steam coils does not greatly affect the temperatures of the delivered air. The amount of steam condensed (heat input) varies.in proportion to the air volume, but the :surface temperature of the steam coils remains about the same. Electric heat is quite different,'.having, a constant input Fig. 1. ' Ceiling Mounted Unit heater Fig. 2. Wall Mounted Unit Heater^ Power supply ; Diffusing ^777777777^7777 Fig. 3. Floor Mounted Unit Heater r. - . Fio. 4. Wiring Diagram for Unit . . Heater .: ,, . of energy. If the volume of .air flow over electric heating elements is changed, and no change is made in the electrical power connections, there will be a corresponding-change in the temperature" of the air delivered. This occurs because the electrical energy input remains constant and thO surface temperature of the heating elements will, vary as is necessary, to force the air to accept all the heat. With, electric heat the total heat is constant unless some compensating action is performed by control. Auto matic variation of the electrical heat input synchronized properly with the air flow can be successfully accomplished by various special methods of control. . .. Electric heaters are useful in balancing the heat distribution in central 708 CHAPTER 41. ELECTRICAL HEATINC fan heating systems. Even in those instances where steam is the principal heat.source, the temperature of individual rooms can be controlled locally by separate1 electric booster heaters. These heaters can be installed: in brarich' ducts or behind the air outlet grilles in each room. With this arrangement, the central heating unit distributes air at an average temper-1 atufe, controlled from athermostat centrally located, such as in the maini return duct. The electric booster heaters may be'controlled by thermo stats mounted in each individual room which-permits -the occupant to . maintain any desired temperature independent of the rest of the building. ELECTRIC STEAM HEATING . Electric steam healing differs from fuel.heating only in the use of electric boilers to generate steam. Electric steam boilers are entirely automatic and are well adapted to intermittent operation. Small electric boilers usually have heating elements of the enclosed metal resistor type im . mersed in the water. Boilers of this construction may be used on either direct or alternating current since the heat is delivered to the water by SECTION A-A Fig. 5. Resistance Type Boiler for Steam or Hot Water contact with the hot surfaces. -To lessen the likelihood that the heating elements will burn out, they should.beof substantial construction, with a low heat density per unit of surface area. Provision should be made for cleaning off deposits of scale which restrict the heat flow. A typical resistance type of hot water or steam boiler is shown in Fig. 5. Large electric boilers are usually Of the type employing water as the resistor. Only alternating current can be used, as direct-current would cause electrolytic deterioration. Large boilers of this kind have electrodes immersed in the water where heat is generated-directly. Electric steam boilers are useful in industrial plants which require limited amounts, of steam for local processes, and for sterilizers, jacketed vessels and pressing machines which need a ready supply of steam. It sometimes is economical to shut down the main plant fuel: burning boilers.when the heating season ends, and to supply steam for summer needs with small electric steam boilers located close to the operation. In general, electric steam heating is confined to auxiliary or other limited applications. If the heating system is designed to use electricity exclusively, steam generating or distributing equipment is superfluous. A diagrammatic'arrangement of, an electrode boiler is shown in Fig. 6. . , 709 HEATINC VENTILATING AIR CONDITIONING: GUIDE 1940 ELECTRIC HOT WATER HEATINC Electric water heating, using an electric boiler in place of a fuel burning boiler, like electric steam heating, is generally confined to auxiliary or other limited applications. The use of insulated water storage tanks in which to store, heat generated by electricity during off-peak hours at extremely low rates, is a development which has some special applications. In this system of heating, the primary storage tank is simply a large, well-insulated, pressure type steel tank, equipped with electric heating elements connected to line with automatic time switches, which also have automatic limit controls for temperature and pressure. The heating system installed in the building' may be of any standard individual radiator or fan-served indirect type or with provisions for the heating and- CHAPTER 41. ELECTRICAL HEATINC hours of off-peak load, while the regular heating element is a stand-by at all times. Storage of this two-element type of water heater is larger than average to carry over the periods when the off-peak element is timed out, without too frequent demands on the regular heating element which takes the higher domestic lighting service rate. Some utilities now offer a schedule which, beyond a stipulated minimum, lowers the rate for all service if an electric water heater is installed. A comprehensive survey covering United States arid Canada shows a rapidly growing use of electric water heaters, although the per cent of saturation, based on the total number of domestic power customers, is still low. Public acceptance is effected by the cost of other competitive fuels, by the electric power rate, and by the temperature of the cold water supply. Competition with other fuels, especially gas, seems to be the major controlling factor. The first cost of electric storage heaters is also greater Fig. 6-. Diagrammatic Arrangement of an Electrode Boiler humidification phases of an air conditioning system. A system of this kind requires very careful design to avoid excessive overall radiation losses during periods of low heat demand. ..It is also important to provide for sudden changes in heat demand. A typical hot water heating boiler is illustrated in Fig. 5. HEATINC DOMESTIC WATER SUPPLY1 Electric water heaters of the automatic storage type for domestic hot water supply are simple and reliable, and in many sections of the country low electric rates have been established by the electric utilities to secure this load. In some districts, rate schedules divide the current used for water heating into two classifications, regular and off-peak. A time switch automatically limits use of the off-peak heating element to the 'Test Results of Electric Water Heaters, by C. G. Hillier (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, November, 1936, p. 632). ' . Fourth Annual Survey, by B. J. Martin {Electric Light and Power, March, 1937). 710 Fig. 7. Piping Arrangement for Connecting Electric Water Heater to Fire-Box Coil Fig. 8. Domestic Hot Water Heater for Off-Peak Service than for gas, owing to the need for larger tank storage due to-off-peak service and slower recuperating capacity. It is often desirable to connect an electric heater to a residential system having a coil in the fire-box of the furnace. In this case it is im portant to make the proper connections in order to benefit by any beat obtained from the furnace and at the same time to prevent dangerous overheating. The proper piping connections are shown in Fig. 7, and in this case the electric heater will only furnish heat when insufficient heat is supplied from the furnace. This arrangement has a further advantage in the summertime in that the bare tank through which the cold water passes on its way to the electric heater serves as a tempering tank, absorbing considerable warmth from the basement air and re quiring the use of less energy in the electric heater. A typical domestic hot water heater as shown in Fig. 8 is arranged with upper and lower heating elements for the usual type of off-peak heating service for which most utilities have especially attractive low power rates. The lower heating element is under the control of the off- 711 7" HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 peak time switch. However, the upper heating element is usually.con nected to the line so that in case the supply of hot water in the tank becomes exhausted the top thermostat can turn on the top heater and heat a small supply of water. The top heater will not heat the water in the tank below its location, but when the off-peak period arrives the lower heater is turned on and the entire tank.becomes heated. . INDUSTRIAL ELECTRICAL HEATING ,, Electric heating elements have been Successfully developed for indus trial work such as annealing, brazing* carburizing, enameling,' forging, ceramic firing, hardening, metal melting, nitriding and process heating; Industrial ovens and furnaces where precise control of temperature is necessary can be very successfully operated with electric resistance ele ments at temperatures as high as 1800 F. For higher temperatures the electric arc or high frequency induction methods are often used. Electric heaters for heating oil to high temperatures for secondary circulation in process work are used as a substitute for superheated steam. Special oil can be electrically heated as high as 700 F and pumped at a pressure just sufficient to cause flow. When used in heating coils or jacketed vessels, this gives a safe and convenient automatic system for moderate-sized installations.' Mixtures of diphenyl and diphenyloxide are used in liquid or vapor form as high temperature, low pressure, heat transfer mediums. Pitch, waxes, and many chemicals are successfully heated by electricity, but require careful design and adequate automatic control. Lacquers and similar surface films can be very effectively dried by the radiation method. Special electric lamp bulbs have been developed which give off a high precentage of infra-red and similar heat rays. These are mounted in very efficient reflectors. A large part of the heat energy is concentrated on the surface of the work, which results in quick drying with very little loss of heat energy. REVERSED CYCLE REFRIGERATION 2_ Reversed refrigeration is frequently referred to as a heat pump since the electric motor driving the refrigerating compressor furnishes the motive power to transfer heat from one temperature to a higher temperature level. Tlie compressor acts as a reversible, refrigerating unit to extract heat frohi the outdoor air in winter and deliver it indoors for heating purposes,,and, by a reversal, to extract heat from the indoor air in summer and discharge'.it outdoors. In normal use a refrigerating machine is arranged to remove heat and *Cooling Homes, A Field for Refrigeration, by A.R. Stevenson, presented at the symposium of the Refrigeration with Gas Committee oT the American Gas Association, April 20,1926. The Heat Rump, An Economical Method of Producing Low-grade Heat from Electricity, by T. G. N. Haldane {Electric Review, Vol. 105, p. 1161-1162, December 27, 1929, and 1. E. E. Journal, Vol. 68, p. 666-675. June, 1930). . . Edison Building Heated and Cooled by. Electricity, by H. L. Doolittle {Power, Vol. 74, p. 384. Septemr ber 8,1931). : .; House Heating by Pump with 5 to 1 Pick-up Ratio, by Gilbert Wilkes and R. E. Marbury {Electrical World, Vol. 100, p. 828. December 17. 1932). ; . . , An AD Electric Heating. Cooling and Air Conditioning System, by Philip Sporn and D. W. McLenegan (A.S.H.V.E. Transactions, Vol. 41,1935, p. 307). ./ Using the Reversed Cycle Refrigerating Principle for a Self-Contained Heating and Cooling Unit, by Henry L. Galson (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning, October. 1935, p. 497). .. . . 712 CHAPTER .41. ELECTRICAL HEATING the heat removed is dissipated to the condenser cooling water. The driving energy is converted into heat most of which is added to the heat removed and extracted. In so-called reversed refrigeration the heat removed together with the heat converted from the driving energy is utilized to heat the building. This conservation of the heat converted from the driving energy enables the reversed refrigeration to show a better performance in heating service than straight refrigeration can show in cooling service. For a detailed description of this cycle see Chapter 24. AUXILIARY ELECTRIC HEATING In conjunction with heating systems of other types, an auxiliary elec trical heating arrangement is a convenient means of caring for mild days in the spring and fall which require little heat to make a building com-, fortable. Likewise, such electrical heating might be used on abnormally cold days to help out the main heating system and by this means, reduce the necessary size of the system. . .. Because of the feeling of comfort that a radiant type heater gives, bathrooms may be heated electrically with this type of heater while the rest of the house is cared for by some other system. Offices and rooms which require heat at periods when the main heating plant is shut down can be conviently heated electrically. Fan type unit heaters delivering warm air at, the floor zone are very effective. CONTROL ; Because the efficiency of electric heat production is the same for large or small units, it is possible to reduce heat waste to a minimum by applying local heating, locally controlled. Radiant heaters are usually, controlled manually but new methods for automatic control are described in Chapter 42 on Radiant Heating. For all convection and fan circulation heaters thermostatic control is essential for economical operation. . For duct systems having a variable volume .of air flow the electric heater control must automatically vary the heat input in coordination; with the changes in air volume and demand for heat. ' " ' CALCULATING CAPACITIES The methods of calculating heat losses outlined in Chapters 6, 7, and 8 may be used for electric heating exactly as for fuel heating. The total heat requirements in Btu per hour may then be converted into the electrical rating of an equivalent heating system by using the equation: --------- ^ jr----------- = kw rating of required electric heating (1) For comparison with steam radiation: ------------- sq ft of steam radiation (2) While many empirical rules based on cubic contents, floor areas, etc., are used in steam heating practice, they should never be used to deter mine si2e of equipment for an electrical heating installation. 713 ' r HEATING VENTILATING AIR CONDITIONING GUIDE 1940 POWER PROBLEMS The first point to determine is the cost of the power which is available for. electric heating. Unlike fuels, there is no uniform cost for electric power because of the; unequal cost of distribution to large and small users. The fact that electricity cannot be economically stored, but must be used as fast as it is generated, makes it impossible to operate power plants at uniform loads; hence, even the time of use may affect the cost of power. Special low rates are sometimes available during certain prescribed hours of use, but wherever the use of power is unrestricted a demand charge based upon the rated connected load of each heating device must form part of the basic rate structure, so that unlike fuel heating, the cost of operating electric heating systems depends not only upon the actual energy used but also upon the demand charge for the available electrical service. Homes are almost universally supplied with lighting current of 115 volts, which can only be used economically for small heaters. Usually the service lines will not permit more than plug-in devices. The Under writers permit approved heaters of 1320 watts or less to be plugged into approved baseboard receptacles. Where homes have 230 volt service for cooking and water heating, and rates are favorable, larger heaters can be installed. For industrial purposes, heaters should be designed to use polyphase power, which is usually supplied at 220, 440 or 550 volts. All polyphase heaters should be balanced between phases. INSULATION The value of building construction which incorporates built-in insu lation to reduce the outward heat loss in winter and the inward heat gain in summer has been placed in the spotlight by the increasing adoption of complete air conditioning. With electric heating, adequate insulation is very important and will pay even better returns-on the investment than for less expensive fuels. 714 Chapter 42 RADIANT HEATING Physical and Physiological Factors, Control of Heat Losses, Rate of Heat Production, British Equivalent Temperature, Application Methods, Calculation Principles, Mean Radiant Temperature, Measurement of Radiant Heating FOR health and comfort, the rate of heat loss from the human body must be controlled, by the aggregate effect of the conditions sur rounding the body, so that the physiological reactions result in a feeling of comfort. Generally, any heating system serves not to add heat to the individual, but to reduce the net rate at which the body loses heat by radiation, convection and evaporation. In convection heating, the heating medium serves to maintain such an air temperature as will give comfort, under existing conditions of humidity and of surrounding surface temperatures. The primary object of radiant heating, on the other hand, is to maintain such an average temperature of the surrounding surfaces, as will give comfort without needlessly heating the air. The difference between convection heating and radiant heating is therefore partly physical and partly physiological. On a cool spring day while standing in the sunshine, one may feel perfectly comfortable, but when a cloud passes over the sun, one will feel much cooler. A shielded thermometer will show no immediate reduction in air temperature, so one actually feels a cooling effect which an ordinary thermometer cannot register. This is because light and heat waves travel at the same speed and are both interrupted by a cloud, or other shield. This proves that radiant heat affects the comfort of the body as definitely as does air temperature. 1: Comfort requires that heat escape from the body at the same rate as it is'generated, by the oxidation of food-stuffs in the body, and in a manner suitable to physiological requirements. Furthermore, the surrounding conditions, themselves, cause changes both in the rate of heat generation in the body, and in the operation of the several methods by which the body loses heat. The feeling of heat or cold results not only from the rate at which the body loses heat, but also from the manner in which the heat is abstracted from the body, and the ease with which the body's heat regulating mechanisms can operate. CONTROL OF HEAT LOSSES Heat is transferred from any warm dry object to cooler surroundings principally by convection and by radiation, the total loss is substantially the sum of these two.- Where the surface is moist, as with the human 715 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 body, heat is also lost through evaporation from both the body surface and the respiratory tract. The rate of heat loss by convection depends upon the average tempera ture difference between the surface of the body and the surrounding air, the shape and size of the body, and the rate of air motion over the body. The rate of heat loss by radiation depends upon the exposed surface area of the body, and upon the difference between the mean surface temperature of the body and the mean surface temperature of the sur rounding walls or other objects. This' latter temperature is called the mean radiant temperature (MRT). Because these two types of heat loss supplement each other, a required rate of total heat loss can result either from a relatively low air tem perature and 'a'relatively high MRT, or vice versa. If the air temperature is reduced, the heat loss from the body by convection is increased, which can be compensated for by raising the MRT so as to decrease the heat- loss by radiation. 7/ ' 7 ............................. : . A heating installation, should provide "comfort for those individuals doing the least physical' work, without causing undesirable changes either in the rate of heat generation, or in the body's heat regulating mechanism. ' ' Rate of Heat Production ; The normal rate of heat production in an average sized sedentary individual is about 400 Btu1 per hour. When considering radiant heating, the evaporation, radiation'and convection losses must be separately studied. The human body is of complicated shape, and radiation takes place freely, only from the exposed outer surface; there are consider able portions of the body such as the legs, arms, lower part ,of head, etc., which radiate most of their heat to other portions. It is necessary to determine the equivalent surface of the body from which heat is radiated and a similar value for convection. The total surface may be assumed as approximately 19.5 sq ft for convection arid'15.5 sq ft for radiation, for an average sized individual. - The loss by evaporation and respiration depends on the temperature and area of the moist surfaces (outside and respiratory) of the body, thq air temperature, air movement and humidity. In air at a temperature of 80 F, this loss for a sedentary individual of average, size will be.approxi- mately 180 Btu pier hour; at 70 F, about -907Btu per hour.; and at 60 F, about 60 Btu per hour. All of these values are relative, because the total will vary materially with change of. position, bodily activity, age, sex, race' etc. .' The balance of the heat generated in the average human body (approxi mately 300 Btu per hour at about.71 F room temperature) is the approxi mate amount of heat given off by radiation and convection. It is difficult to determine the exact proportions of these two; but it appears that if the body loses about 190 Btu per hour by radiation (or 12.25 Btu per hour per square foot of radiating body'surface)', the greatest comfort ' lA.S.H.V.E. Research Report No. 830--Heat and Moisture Losses from the Human Body and Their . Relation to Air Conditioning Problems, by F. C. Houghten, W..W. Teague, W. E. Miller, and W. P. Yant (A.S.HlV.E. Transactions, Vol. 35, 1939, p. 245). ............ ' 716 CHAPTER 42. RADIANT HEATING will result. This leaves about 110 Btu per hour.to be lost by convection (or 5.65 Btu per hour per square foot of converting body surface). "' The mean surface temperature of the human body, including the whoie area hot -only of exposed skin but also of clothing and hair, Has been estimated variously at frorifi 75 F (particularly in England) up to 83 F. (in America). Further research and experience will be needed to finally derive the most suitable value for the American climate. The final figures will vary with sex, age:, clothing, etc;, but will probably come between these extremes. . The rnean surface, temperature of an inert body, which will cause given rates of heat loss by radiation and by- convection in a uniform environment, having a given air temperature and a given mean wall temperature, may be calculated from fundamental equations for radiation and* natural convection; but substituting comparable cylinders for the irregular human1 body. 1 " Heilman2 gives the following equations; ; -(*)] m ... ^(f)"S(ferX(r.-T.)" ,3, where - - ' Hr = heat loss by radiation, Btu per square foot per hour. ' `Hz = heat loss by convection, Btu-per square foot per hour. T, =' absolute temperature of the body surface, degrees Fahrenheit. Tv = absolute temperature of the walls, degrees Fahrenheit, Ta = absolute temperature ol the air, degrees Fahrenheit. ,, T, + Ta . 7m - 2 1 . . . .. D = diameter of cylinder, inches. e = the ratio of actual emission to black body emission, * - : If it is assumed that an average adult.has a height of 5 ft 8 in. and a body surface of 19.5.sq ft for convection, and 15.5 sq ft for radiation, an equivalent effect can be worked out for two cylinders, 5 ft 8 in. high by 13.15 in. diameter and 10.45 in. diameter; respectively. However, while the effects on a cylinder (of a particular size and shape) may be used to estimate average similar effects on the human body, it should be remembered that the heat-loss from, the body varies greatly. Every movement alters not only its shape, but also the-velocity of the air passing over it and the surface exposed. to radiation. This fact renders the results of any such computation only approximate. : :. BRITISH EQUIVALENT TEMPERATURE The British Equivalent Temperature (BET) is the mean temperature of the entire environment which is effective in controlling the rate of sensible heat loss from a black body in still air when this body has a surface temperature equal to' that of the human body, arid a size comparable (A SM:E\ 717 suam Pr SrCian. HEATING VENTILATING AIR CONDITIONING CUIDE 1940 to the human body. The BET is, therefore, a function of both the air temperature and the mean radiant temperature of the surrounding objects. Its numerical value in a uniform environment (walls and air at the same temperature) is equal to the temperature of the walls and air. In a non-uniform environment (walls and air at different temperatures), the BET for America is at present considered to be equivalent to that of a uniform environment in which a body with an 83 F surface ternperature will lose sensible heat at the same rate as in the given non uniform environment. As originally defined (in England) the BET was based on a body surface temperature of 75 F, but 83 F has been accepted as more nearly conforming with American practice3. The most suitable temperatures depend in part on the clothes worn by. the individual, which explains why ladies in evening dress require a higher BET, for comfort, than a man having only hands and head uncovered. The higher the BET, the less the heat loss from the body, as the rate of loss in still air is approximately proportional to the difference between the BET and the mean body surface temperature. If the BET were 83 F, there could be no sensible heat loss from a surface at that temperature; so the temperature of a normal body surface would have to rise to a point where the heat generated in the tissues could be dissipated. With a BET of about 65 to 70 F, the sensible heat losses from the assumed average individual will approximate those stated on page 716. Actual experience in the United States has shown that with about half of the ceiling surface heated to about 115 F in midwinter weather, it is practical to maintain comfort with air temperatures of 65 F or less. APPLICATION METHODS There are several methods of applying radiant heating, as follows: 1. By warming the interior surfaces of the building. Pipe coils are embedded in the concrete or plaster of the walls or ceilings, the heating medium being hot water circu lating through the pipe coils. These coils are generally constructed of small pipe spaced about 6 in. apart (Fig. 1). This has the effect of warming the entire concrete or plaster surface in which the pipes are embedded. Since the temperature of the heating medium should never exceed about 140 F (due to the possibility of cracking the plaster) the area of the panel must be sufficient to supply the requisite quantity of heat at this low temperature. When carefully designed, this method produces very comfortable results and great operating economy, but offers some slight obstacles when alterations or additions to the building are desirable. Normally the hot water circulation is maintained by means of a circulating pump and facilities have to be provided to eliminate all air at the top of the system. AH.of the pipes are welded together and tested after erection to a hydraulic pressure of 300 lb per square inch. . 2. By placing hot water or steam pipes under the floor. With this arrangement the whole floor surface of a room is raised to a temperature sufficient to give comfortable conditions. This method is used for schools and hospitals where large quantities of outside air are desirable (Fig. 2). In some cases special floors are constructed in sections so that a whole floor can be lifted to examine the pipes. The floor surface may be of concrete, wood blocks, marble or any other material unaffected by heat. Pipes under the floor may be larger than those embedded in the plaster walls and ceilings. 3. By circulating warm air through shallow ducts under the floor. In this design the entire floor surface of a room is heated as in method 2. This method was used occasion- *A.S.H.V.E. Research Report No. 962--Application of the Eupatheoscope for Measuring the Per formance of Direct Radiators and Convectors in Terms of Equivalent Temperatures, by A. C. Willard. A. P. Kratz, and M. K, Fahnestock (A.S.H.V.E. Transactions, Vol. 39. 1933. p. 303). *. 718 CHAPTER 42. RADIANT HEATINC ally in the Roman Empire, and while being more expensive in construction, is effective and quite suitable for cathedrals and large public buildings (Fig. 3). To provide a uniform-floor temperature, special consideration should be given to the design of the air ducts so that equal heat distribution is obtained. . Fig. 1. Pipe Coils Located in Interior Wall Surfaces Fig. 2. Arrangement of Continuous Pipe Coil in Floor Construction 4. By attaching separate heated metal plates or panels to the interior surfaces. These plates or panels are placed either in an insulated recess so that the surface of the panel is flush with the surface of the walls or.ceilings, or they may be secured to the face of the wail. They may be covered with wood veneers and decorated to harmonize with other -parts of the room, or they can be cast into panels to imitate oak or other wood designs. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 With flat plate panels it is common practice to use a frame of plaster, wood, metal or composition to allow for expansion. These plates may be heated with either hot water or steam and connected to an ordinary radiator system. 5. By electric heated metal plates or panels. These plates or panels are either placed in insulated recesses of walls or ceilings or fastened to the construction, as found desirable. They should not have a surface temperature much above 200 F; some have a much higher surface temperature but a lower temperature gives a more comfortable condition and is more efficient. ' 6. By electrically heated tapestry mounted on screens and on the wall. For this purpose the screen is woven with an electric continuous conductor. Such screens are useful to plug in at any position for emergency local heating without taking care of a large room or office. Note. If all of a heating panel is installed at one end of a large room there may be a marked difference between the BET on the two sides of the body. It is usually desir able, therefore, that the heat be distributed at different parts of the walls and ceilings so that no uncomfortable effects will be felt from unequal heating. pun . Air ducts in floor space Fig. 3. Diagram of Air Ducts for Floor Heating CALCULATION PRINCIPLES The calculations for radiant heating are entirely different from those for convective heating. The purpose of the latter is to determine, and compensate for the rate of heat loss from the room, when maintained in the desired condition; but radiant heating involves the regulation of the rate of heat loss from the human body. The first step in the calculations for radiant heating of a given room is to ascertain the desired MRT; next, to decide at what temperature the heating surface shall operate; then, to compute the size and disposition of the heating surfaces required to produce this MRT; and last, to provide convected heat for the required number of, air; changes. Mean Radiant Temperature ' ~ ............ - If the entire interior surface of a room were at the sanie temperature, this would be the MRT. Such a condition seldom exists, however, since in different parts of a room, with some surfaces exposed to the outer air, the actual surface temperature varies greatly with the construction and exposure of different sides of the enclosure. It is therefore necessary to calculate the thermal mean of these interior surface temperatures. This is not the arithmetic average of the various actual surface tem peratures, but the radiant temperature which corresponds to the average 720 CHAPTER 42. RADIANT HEATING of the several rates of heat emission (Btu per square foot) from the several surfaces. The emission at any given surface temperature, for any stated "emissivity factor, and also the MRT corresponding to any average ` emission, can be obtained directly from Table 1. For example; if the emissivity of the surface is 0.9, l sq ft of surface at 50 F will emit 104.9 Btu per square foot per hour to surroundings at absolute zero. Table 1. Total Black Body Radiation to Surroundings at Absolute Zero3 ' Bodt- " Radiation in Bto per square foot per boor OB - Mbak Radiant Tbmpbb emitted to surroundings with a tempera ture of absolute zero by bodies at various temperatures and with emissivity. factor $ "'ATUBB Deg Fahr e 1.00 0.95 e 0.90 e 0M 1 Boor OH Mban [Radiant Temper atubb Deg Fahr Radiation in Btu per square foot per boor emitted to surroundings with a temperature of-absolute . zero by bodies at various temperatures and with emissivity factor . . 1.00 0.95 ` - 0.90 0.80 ' 30 99.3 94.3 35 103.5 98.3 40 107.6 102.4 45 112.1 106.5 ..-.46 .,112.9 107.3 ; 47 `113.9 108.2 '48 1 114.8 109.1 :49: .115.6 109.9 so 116.5. 110.6 SI 117.5 111.6 52 118.4 112.5 'S3-.. 119.4 113:4 54 120.2 114.2 55 121.1 115.1 -56 122.1. 11610 57. 123.1 117.0 . 58 124.0 117.8 59 124.9 118.6 : 60 125.8 119.5 61 126.6 120.3. - 62 127.7 121:4 63 128.6' 122.2 : ,64 129.6 123.1 65 130.5 124.0 66- 131.6 125.0 67 132.5 125.9 6S 133.5 126.8 69 134.5 127.8 .,,70 135.5 .128.8- 89.4 79.4 71 136.5 129.6 93.2 82.8 72 137.4 130.5 96.8 86:1 73 138.4 131.5 100.9. 89.7 74-f 139.6 132.6 101.6. 90.4 75 141.0 133.9 102.5' 91.1 80 146.6 139.4 103.4 91.9 85 152.3 144.6 104.1. 92.4. 90 : 157.9 149.9 104.9 105.8 93.2 100 94.0 no 169.6 181.6 161.1 172.5 106.5 94.7 120 194.8 185.0 107.4 95.5 130 210.1 199.6 108.2 96.2 140 223.2 . . 212.1 109.0 96.9 150 237.1' ' 225.2 .109.9: :97.7 160 . 251.1 :238.8 110.9. 98.5 170 270.5.. . 257.0 lli.6 99.2 180 288.0 273.8 112.4 99.9 190 306.5 291:0 133:4: 100.7 200 "325.2 309.0 114.0 101.4 210 .348.0 330.6 .114.9 102.2. 220 , 371.5 . 353.0 115.8 102.9' 250 437.8 ' 415.9 116.7 103.7 300 575.0 1 546.1 117.5 104.4 350 740.0 - . 703.0 118.4 -105.4 400 942.1 895.0 119.3 106.0 450 1176.0. . 1117.0 120.1 106.8 500 1464.0 1390.0 121.1. :107.6.1 5$0 1791.0 1701.0 .121.9 . 108.4 6h0 2405.0 2284.0 122.9 123.6 124.5. 125.6 126.9 132.0 1371 142.1 152.6 163.5 175.4 189.1 201.0 213.5 226.0 243.5 . 259.1 275.8 292.8 313.1 334.4 394.0 517.5 666.0 847.5 1059.0 1318.0 1613.0 2165.0 109.3 109.9' 110.6 111.7 112.8 117.4 121.9 126.4 135.7 145.4 155.9 .168.1 178.5 . 189.7 201.0 216.4 230.4 245.1 260.3 278.4 297.1 350.2 460.0 592.0 753.5 94i.O 1171.0 1434.0 1925.0 . "These factors are calculated from the formula where 0 e T --Q / 0.1723 X T*\ L ioo.ooo.ooo ) total black body radiation, Btu per square foot per hour.: * emissivity. . .: _ ; absolute temperature, degrees Fahrenheit. ................; ' Such a determination of the amount of radiant heating surface heeded in a room (to maintain a desired MRT), requires knowledge of the type of heating, and the surface temperatures bf the unheated surfaces, which latter can only be estimated-^--but with a considerable degree of accuracy after some experience. ---------- ---- - --....... ' --.....----- - 721. HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Detailed Computation Method The area in square feet of each type or temperature of surface, hori zontal or vertical, is multiplied by the emission value corresponding to its actual surface temperature. These products are added together to give the total radiant heat effect, inside the room from all surfaces. The difference between the actual average radiant heat effect and 142 Btu per hour per square foot (the radiation from a surface at 83 F, with an emissivity of 0.95) is the Btu per square foot per hour which would be lost by radiation from a body at 83 F. If the rate, at which it is desired that heat be lost from the body by radiation, be assumed, the mean radiant emission from the walls required to give this desired rate can be determined from Table 1; and multiplying by the total surrounding area will give the desired total radiant heat effect. The difference between the desired and the actual total radiant emission represents the additional heating effect which must be. supplied by the hot surfaces to be installed. The temperature of the proposed hot surface must then be selected, and its emission per square foot at that temperature determined from Table 1. The difference between this emission, and that of the unheated surface, is divided into the total amount of additional heat needed, and the quotient will be the area of the required heating'surfaces. ; It is evident that this method of calculation depends for its accuracy on a correct estimate of the ultimate surface temperatures naturally attained by the actual wall, window, ceiling and floor surfaces. Unless positive ventilation with tempered, air is provided, the amount of heat given off by convection from the same heating surfaces should also be determined, checked against the tempering requirements of whatever outside air can in any way enter the room, and supplemented if necessary, by additional convection heating, to maintain the desired air temperature. As this air temperature will usually, be from 6 to 8 F lower (for comfort) than with purely convective heating, the relative humidity will be appreciably higher at a given dew-point, and there will be a marked saving in fuel for tempering, humidification and conductive heat loss from the building. Example 1. The surface areas, temperatures, and emissions for a room having a volume of 5760 cu ft are given in Table 2. The figures for temperatures are fairly Table 2. Surface Areas, Temperatures and Emissions for a Room of 5760 Cu Ft Abba 8q Ft External Wall..................... Glass....................................... Inner Wall............................ Ceiling........... ..................... 297 279 480 480 480 Total............................. 2016 Assumed 8ubpacb Temperatube (Deo Fabb) 50 45 55 55 55 Heat Emission (Btu Per Sq Ft peb Hour) Total Heat Emibbion pbom Abba (Btu peb Hour) 110.6 106.5 115.1 115.1 115.1 32,850 29,710 55,250 55,250 55,250 228,310 722 CHAPTER 42. RADIANT HEATING representative of American practice with well-built walls, and the heat emission is based on an emissivity of 0.95 which approximates that of most paints and building materials. The mean radiant emission of the room is 228,310 -s- 2016 = 113.2 Btu per square ' foot per hour which, as seen from Table 1 corresponds to an MRT of 53 F for an average emissivity of 0.95. For an average individual, having a surface area of 15.5 sq ft with an average surface temperature of 83 F, the heat given off by radiation (calculated by means of Equation 1) is 217 Btu per hour, or 14 Btu per square foot per hour. This corresponds to an environ mental emission of 142 (the total radiation corrected to 83 deg) --14 = 128 Btu per square foot per hour, and (according to Table 1) to an MRT of 69.2 F, both of which are higher than the actual values available in the room. In order to determine the amount of radiating surface necessary to maintain the MRT at 69.2 F, ceiling panels are assumed with a surface temperature of 160 F, which is approximately the mean temperature for metal plates heated by hot water. The 2016 sq ft total area of the surfaces of the room, multiplied by 128 (the emission in Btu per square feet per hour, necessary to balance a body surface temperature of 83 F) gives a total desired emission of 258,048 Btu per hour. Enough radiant heating surface must be installed to increase the total radiant heat emission from 228,310 Btu per hour to 258,048 Btu per hour. The difference between these figures is 29,738 Btu per hour. From Table 1, the emission per square foot at 160 F is 238.8 Btu per square foot, or 123.7 Btu per square foot more than for the unheated ceiling surface (at 55 F). The required radiant heating surface is, therefore, 29,738 -s- 123.7 = 240.4 sq ft. This surface, suitably placed, would raise the MRT to the degree required for comfort, and maintain it at that value. Such calculations may be simplified, by preparing tables showing at the usual temperatures the area of hot surface required to bring each square foot of actual wall or other surface up to one or more desired . standard MRT's. MEASUREMENT OF RADIANT HEATING Convection heating, intended to maintain a given air temperature, is best measured by thermometric methods, which indicate the air tem perature, and not the rate of heat loss from the human body. Radiant heating, on the other hand, aims to control this rate of heat loss and can be measured only by calorimetric methods, that is, by determining directly the rate of heat loss from some object, maintained at the surface temperature of the body, irrespective of air temperature. Although a definite BET is needed, the MRT and the air temperatures may .both vary in opposite directions provided the sensible heat loss by radiation and convection from a surface at 83 F is maintained constant within reasonable limits. The apparatus for this purpose consists essentially of a hollow sphere or cylinder, maintained at the accepted mean surface temperature of the human body, together with an accurate means (usually electrical) of measuring the varying rate of heat supply required to maintain this exact temperature. This instrument, the eupatheoscope, is readily adapted to function like a thermostat so as to turn heat on or off, when the desired temperature of 83 F, or any other predetermined surface temperature of the vessel, decreases or increases as a result of changes in the BET. Another instrument, at present available only for British practice as it is designed for a surface temperature of 75 F, consists of a blackened copper sphere of 6 in. diameter, in which a cylindrical sump contains a volatile liquid. A small electric heating coil creates in the sphere a 723 tjwsp: HEATING VENTILATING AIR CONDITIONING GUIDE 1940 vapor pressure which is constant, as long as the total heat loss from the sphere is of the desired rate. If the BET becomes too high for comfort, a greater vapor pressure results from the smaller heat loss from the sphere, acts on a diaphragm, and 'turns 'down 'the supply of heat to the room. With falling. BET, the reverse action occurs. ; For testing work, the globe thermometer is a very useful instrument.. It Consists of an ordinary, mercury thermometer, with its bulb placed in the center of a sphere from 6 to 9 in. in diameter, usually made of thin copper and painted black. The temperature thus recorded is termed the radiation-convection-temperature. : '. . REFERENCES '^ Panel Warming, by L. J. Fowler (A.S.H.V.E. Transactions, Vol.-36, 1930, p. 287). ` Room Warming by Radiation, by A. H. Barker (A;S.H.V.E. Transactions, VoK 38, 1932, p. 331). What Will be the Future Development of Heating and Air Conditioning, by W. H; Carrier (Healing, Piping and Air Conditioning, January,. 1933, p. 16). , American Practice in Panel Heating, by L. L. Munier (Heating, Piping and Air Conditioning, June, 1937, p. 424). .. .. r... . ... Panel Heating in the British Embassy, by Alfred L. Jaros, -Jr. and Richard A. Wolff (Heating and Ventilating, May and June, 1930). . Calculations for Radiant Heating, by T.'Napier Adlam (Heatingand Ventilating, October, 1931). . . -..... . .; . Notes on" Electric Warming with Special Reference to Low. Temperature Panel Systems, by R. Grierson (Proceedings of The Institution of Heating and Ventilating Engineers, London, Vol. 28, 1929). ' Notes on the Theory of Radiant Heating, by C. G. Heys Hallett (Proceedings of The Institution of Heating and Ventilating Engineers, London,' Vpl. 29, 1930). Radiant Heat, by A. F. Dufton (Proceedings of The Institution of Heating and Ven tilating Engineers, London, Vol. 30,1931). ' . . ' Panel Heating, by C. M. Oates (Proceedings of The Institution of Heating and Ventila ting Engineers, London, Vol. 30, 1931). . , Principles of Calculation of Low Temperature Radiant Heating, by A. H. Barker (.Proceedings of The Institution of Heating and Ventilating Engineers, London, Vol. 30; 1931). ' i ` Radiant Heat, by A. F. Dufton (Proceedings of The Institution of Heating and Ven tilating Engineers, London, Vol. 31, 1932). : . ' -V .' - : 727 "... .Chapter 43 DISTRICT HEATING . Steam Distribution Piping, Selection of Pipe Sizes, Provision for .Expansion, Capacity of Returns with Various Grades, Conduits for Piping, Pipe Tunnels, Inside Piping, Steam Re quirements, Fluid Meters and Metering, Rates, Utilization, ' Automatic Temperature Control . .. ... THOSE phases of district heating which frequently fall within' the _ province of the heating engineer are-outlined here with data'and information for solving incidental problems in connection with institutions and factories. Some data are included to cover the' piping-peculiar to heating systems which are to be supplied with purchased steam. A com plete district heating installation should not,be attempted without a thorough study of the entire, problem by. men competent and experienced in that industry. ' ............. .... ; . STEAM DISTRIBUTION PIPING , The methods used in district heating work for the distribution of steam are applicable to any problem involving the supply of steam to a group of buildings. The first step is to establish the route of the pipes, and in this matter the local conditions so fully control the layout that little can be said regarding it. Haying established the route of the pipes, the next step is to calculate the pipe sizes. In district heating work it is common practice to design the piping system on the basis of pressure drop. The initial pressure and the minimum permissible terminal pressure are specified and the pipe sizes are so chosen that the required amount of steam, with suitable allowances for future increases, will be transmitted without exceeding this pressure drop. The steam velocity is therefore almost disregarded and may reach a very high figure. Velocities of 35,000 fpm are not con sidered high. By the use of this method the pipe sizes are kept to a minimum with consequent savings in investment. The steam flowing through any section of the piping can be computed from a study of the requirements of the several buildings served. In general a condensation rate of 0.25 lb per hour per square foot of equiva lent heating surface is a safe figure. This allows for line condensation which, however, is a small part of the total at times of maximum load. Miscellaneous steam requirements such as laundry, cooking, or process should be individually calculated. The steam requirements for water heating should be taken into account, 725 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 but in most types of buildings this load will be relatively small compared with the heating load and will seldom occur at the time of the healing peak. Unusual features such as large heaters for swimming pools should not be overlooked. The pressure at which the steam is to be distributed will depend upon (1) boiler pressure, (2) whether exhaust or live steam, (3) pressure require ments of apparatus to be served. If steam has been passed through electrical generating units, the pressure will be considerably lower than if live steam, direct from the boilers, is used. The advantages of low pressure distribution (2 to 30 lb per square inch) are (1) smaller heat loss from the pipes, (2) less trouble with traps and valves, (3) simpler problems in pressure reduction at the buildings, and (4) general reduction in maintenance costs. With distribution pressures not exceeding 40 lb per square inch there is little danger even if the full distribution pressure should build up in the radiators through the faulty operation of a reducing valve; but with pressures higher than this a second reducing valve or some form of emergency relief is usually desirable to prevent excessive pressures in the radiators. ' The advantages of high pressure distribution are (1) smaller- pipe sizes and (2) greater adaptability of the steam to various operations other than building heating. The different kinds of apparatus which frequently must be served require various minimum pressures. Kitchen equipment requires from 5 to 15 lb per square inch, the higher pressures being necessary for apparatus in which water is boiled, such as stock kettles and coffee urns. An increased amount of heating surface, which is easily obtained in some kinds of apparatus, results in quicker and more satisfactory operation at low pressures. For laundry equipment, particularly the mangle, a pres-sure of 75 lb per square inch is usually demanded although 30 lb per square inch is sufficient if the mangle is equipped with a large number of rolls and if a slow rate of operation is permissible. . Pressing machines and hospital sterilizers require about 50 lb per square inch. -- PIPE SIZES . The lengths of pipe, steam quantities, and initial and terminal pressures having been chosen, the pipe sizes can readily be calculated by means of the Unwin pressure drop formula. This is one of several formulas which may be used. Unwin's formula, which gives pressure drops slightly larger than actual test results, is as follows: ' 0.0001306 W'L (l + P= " dip : where P = pressure drop, pounds per square inch. W weight of steam flowing, pounds per minute. L -- length of pipe, feet. . D ** inside diameter of pipe, inches. d = average density of steam, pounds per cubic foot. (1) This formula is similar to the Babcock formula given in Chapter 16. 726 CHAPTER 43. DISTRICT HEATING Information on provision for expansion will be found in Chapter 18. - Where steam and return piping are installed in the same conduit, the return piping usually follows the same grade as the steam piping. In general, the condensation is pumped back under pressure. Where the condensation returns by gravity, Table 1 gives the sizes of the return piping. It is evident that at points where the grade is great, smaller pipes can be installed. ' CONDUITS FOR PIPING Conduits for steam pipes buried underground should be reasonably waterproof, able to withstand earth loads and to take care of the expan sion and contraction of the piping without strain or stress on the couplings, or without affecting the insulation or conduit. Expansion of the piping must be carefully controlled by means of anchors and expansion joints or bends so that the pipes can never come in contact with the conduit. Anchors can be anchor fittings or U-shaped steel straps which partially encircle the pipes and are firmly bolted to a short length of structural or cast steel set in concrete. In general, cast steel is preferable to struc tural steel. Table 1. Capacity of Returns for Underground Distribution Systems in Pounds of Condensate per Hour Site or Pipe In. i U4 m 2 3 4' 5 6 8 10 12 6* 448 1740 2700 4980 13900 30900 54800 90000 190000 344000 555000 V 998 2490 4190 7380 22500 44800 79800 138000 277000 498000 798000 Pitch or Pm pb 100 Ft V 1890 3990 5740 10700 30900 64800 120000 187000 404000 724000 1148000 3' 2240 4880 7480 13900 37400 79700 144800 237000 508000 900000 1499000 y 3490 6480 9480 16900 50400 105000 195000 312000 660000 1190000 1990000 10' 5490 9480 14500 24900 74800 154000 294000 449000 938000 -- 20' 7490 13500 20900 36900 105000 229000 418000 *Size of pipe should be increased if it carries any steam. . In laying out underground conduits the following points should be borne in mind: 1. The depth of the buried conduit should.be kept at a minimum. Excavation costs are a large factor in the total cost. 2. An expansion joint, offset, or bend should be placed between each two anchors. 3. If the distance between buildings is 160 ft or less and the steam line contains highpressure steam, the line may be anchored in the basement of one building and allowed to expand into the basement of the second building. If the steam line contains low-pressure steam (up to 4-lb pressure), this method may be used if buildings are 250 ft or less apart. 4. If the distance between buildings is between 150 ft and 300 ft and the steam line contains high-pressure steam, the lines should be anchored midway between the buildings and allowed to expand into the basements of both buildings. If the steam line contains low-pressure steam this method may be used if buildings are between 250 ft and 600 ft apart. No manhole is required at the anchor, and a blind pit is all that is.necessary, 5. For longer lines, manholes must be located according to experience, physical con ditions and the expansion value of the type of expansion joint or bend that is used. The 727 . HEATINC VENTILATINC AIR CONDITIONING GUIDE 1940 minimum number of manholes will be required when an expansion bend, or an anchor with double expansion joint, is placed in each manhole and the pipes are anchored mid way between manholes. ... 6. A proper hydrostatic test should be made on the assembled line before the insula tion and the top of the conduit are applied. The hydrostatic test pressure should be one and one-half times the maximum allowable pressure and it should be held for a period of at least two hours.without evidence of leakage. In'any case the pressure should be ho less than 100 lb per square inch. ". . There are many types of conduits, some of which are manufactured products and some of which are built in the field. The styles and con struction of conduits commonly used may be classified as follows. Some of the more common forms are illustrated in Fig. 1. ' Top tUe ; Fig. 1. Construction Details of Conduits Commonly Used ... Wood Casing: - The pipe is enclosed in'a cylindrical casing; usually having a wall 4 in. thick and built of segments which are bound together by a wire wrapped spirally around the casing. The casing is lined with bright tin and coated with asphaltum. The pipe is supported on rollers'carried in a bracket which fits-into the casing. The "lengths of casing are tightly fitted together with a male and female joint. This form of conduit isi illustrated in Fig. 1 at A.. The casing rests on a bed of crushed stone with tile drains laid below. The tile drains are of 4-in. field tile or vitrified sewer tile, laid with open joints. Filler Type: The pipes are supported on expansion rollers properly supported from the conduit or independent masonry base. The pipes are protected by a split-tile conduit, and the entire space between the pipes and-the tile is filled with an insulating filler. Thus the:pipes are nested and-the insulation between them and the tile effectively prevents' circulation of air. The conduit is placed on a bed of gravel or crushed rock from 4 to 6 in. thick, which is extended upward so as to come about 2 in.:above the parting lines of-the tile. A tile underdrain is placed beneath the conduit throughout,the entire length and is connected to sewers or to some other point of free discharge. At B and D in Fig. T are, shown two forms of tile conduit of the filler type. , ,. ;;; Circular Tile or Cast-Iron Conduit: The pipes are carried on expansion rollerssupported on a frame which rests entirely on the side shoulders of the base drain foundation. The pipes are protected by a sectional tile conduit, scored for splitting, or a cast-iron conduit, both being.of the bell and spigot type. The conduit has a longitudinal side joint. 728 CHAPTER 43. DISTRICT HEATING for cementing, after the upper half of conduit is in place, so shaped that the cement is keyed in place while locking the top and bottom half of the conduit together with a water-tight vertical side joint. The cast-iron conduit has special side locking clamps in addition to the vertical side joint. The entire space between the conduit and the pipes is filled with a water-proofed asbestos insulation. The conduit is supported on the base drain foundation, each section resting on two sections of the base drain, thus inter locking. The base drain is so shaped that it provides a cradle for the conduit, resting solidly on the trench bottom and providing adequate drainage area immediately under the conduit. The underdrain is connected to sewers or some other point of free discharge. For tile conduit the base drain is vitrified salt glazed tile and for cast-iron conduit it is either extra.heavy tile or cast-iron. A free internal drainage area is also provided to carry away any water that may collect on the inside of the conduit from a leaky pipe or joint in the conduit. Broken stone is filled in around the base drain and up to the vertical side joint. The broken stone is covered with an asphalted filter cloth to prevent sand from sifting through the broken stone and clogging the drainage area of the base drain. The tile conduit is made in 2-ft lengths and the cast-iron conduit in 4-ft lengths, cast in separate top and bottom halves. Special reinforcing ribs give the cast-iron conduit ample strength with minimum weight. Insulated Tile Type: The insulating material, diatomaceous earth, is molded to the inside of the sectional tile conduit. The space between the pipes and the insulating con duit lining may also be filled with insulation. The pipes are carried on expansion rollers supported on a frame which rests on the side shoulders of the base drain foundation. This type of conduit has the same mechanical features as those described under the heading Circular Tile or Cast-Iron Conduit. Sectional Insulation Type (Tile or Cast-Iron): Each pipe is insulated in the usual way with any desired type of sectional pipe insulation over which is placed a standard water proof jacket with cemented joints. The pipes are enclosed in a sectional tile or cast-iron conduit as described under the heading Circular Tile or Cast-Iron Conduit. Sectional Insulation Type (Tile or Concrete Trench): A type of construction frequently used in city streets,, where service connections are required at frequent intervals, the pipes are insulated as described in the preceding paragraph, and are enclosed in a box dr trench made either entirely of concrete, or with concrete bottom and specially con structed tile sides and tops. The pipes are supported on roller frames secured in the concrete. At C and E, Fig. 1, are shown two tile conduits using sectional insulation. In these particular designs the space surrounding the pipe is filled partially or wholly with a loose insulating material. The use of loose material in addition to the sectional insula tion is, of course, optional and is only justifiable where high pressure steam is used. The conduit shown at F is of a similar type and has the advantage of being made entirely of concrete and other common materials. Sectional Insulation Type (Bituminized Fibre Conduit): Each pipe is individually insulated and encased in a bituminized fibre conduit. The insulating material is 85 per cent carbonate of magnesia sectional pipe covering, applied in the usual manner as on overhead pipes, except that bands are omitted. After every fifth section of magnesia covering there is applied a short, hollow section of very hard asbestos material in the bottom portion of which rests a grooved-iron plate carrying ball-bearings upon which the pipe rides when expanding or contracting. This short expansion section is of the same outside diameter as the adjacent 85 per cent magnesia covering. Over the pipe covering and expansion device there are placed two layers of bituminized fibre conduit with all joints staggered, and the surface of each conduit is finished with liquid cement. Conduits are placed on a bed of crushed rock or gravel, approximately 6 in. deep, and this is extended upward to about the center line of the conduit when trench is backfilled. Underdrains leading to points of free discharge are placed in the gravel or crushed rock beds. Special Water-Tight Designs: It is occasionally necessary to install pipes in a very wet ground, which calls for special construction. The ordinary tile or concrete conduit is not absolutely water tight even when laid with the utmost care. The conduit shown at G, Fig. 1, is of cast-iron with lead-calked joints and is water-tight if properly laid. It is obviously expensive and is justified only in exceptional cases. A reasonably satisfactory construction in wet ground is the concrete or tile conduit with a water-proof jacket enclosing the pipe and its insulation, and with the interior of the conduit carefully drained to a manhole or sump having an automatic pump. It is useless to install external drain tile when the conduit is actually submerged. 729 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Fig. 2V Connections for Reducing Valves of Size Less than 4 In. PIPE TUNNELS Where steam heating lines are installed in tunnels large enough to provide walking space, the pipes are supported by means of hangers or roller frames on brackets or frame racks at the side or sides of the'tunnel. The pipes are insulated with sectional pipe insulation over which is placed a sewed-on, painted canvas jacket or a jacket of asphalt-saturated asbestos water-proofing felt. The tunnel itself is usually built of concrete or brick and water-proofed on the outside with membrane water-proofing. On account of their relatively high first cost as compared with smaller conduits, walking tunnels are sometimes not installed where provision for the heating lines is the only consideration, but only where they are required to accommodate miscellaneous other services or provide underground passage between buildings. , OVERHEAD DISTRIBUTION In ; some industrial and institutional applications, the distribution piping may be installed, entirely or in part, above ground. This method of construction has the advantage of requiring no excavation and being easily maintained. ' CHAPTER 43. DISTRICT HEATING Pressure reducing valve Customer's pressure reducing valve Fig. 4. American Standard 175 lb S. S.P. Pipe to be standard weight. Continuous-flow type float trap Steam Supply Connection when Using Two Reducing Valves INSIDE PIPING Figs. 2 and 3 show typical service connections used for low pressure steam service. As shown in Fig. 2, no by-pass is used around the reducing valve on sizes less than 4 in. Fig. 3 illustrates the use of a by-pass around reducing valves 4 in. and larger. This latter construction permits the operation of the line in case of failure in the reducing valve. In the smaller sizes, the reducing valve can be removed, a filler installed, and the house valve used to throttle the flow of steam until repairs are made. Fig. 4 shows a typical installation used for high pressure steam service. The first reducing valve, effects the initial pressure reduction. The second reducing valve reduces the steam pressure to that required. Most district heating companies enforce certain regulations regarding the consumer's installation, partly to safeguard their own interests but principally to insure satisfactory and economical service to the consumer. There are certain fundamental principles that should be followed in the design of a building heating system which is to be supplied from street mains. Although some of these apply to any building, they have been demonstrated to be especially important when steam is purchased. Return main Fig. 3. Connections for.Reducing Valves of Size 4 In. and Larger, and for Expanded Valves 730 731 CHAPTER 43. DISTRICT HEATING 1. Provision should be madefor conveniently shutting off the steam supply at night and at other times when heat is not needed. _ It has been thoroughly demonstrated that a considerable amount of heat can be saved by shutting off steam at night. Although there is, in some cases, an increased consumption of heat when steam is again turned on in the morning, there is a large net saving which may be explained by the fact that the lower inside temperature maintained during the night obviously results in lower heat loss from the building, and less heat need therefore be supplied. Steam can be entirely shut off at night in most buildings even in very cold weather without endangering plumbing. It is necessary, however, to have an ample amount of heating surface so that the building can be quickly warmed in the morning. Where the hours of occupancy differ in various parts of the building, it is good practice to install separate supply pipes to the different parts. For-example, in an office building with stores or restaurants on the first floor which are open in the evening, a separate main supplying the first floor will permit the steam to be shut off from the remainder of the building in the late afternoon. The division of the building into zones each with a separately controlled heat supply is sometimes desirable, as it permits the heat to be adjusted according to variations in sunshine and wind-. S. Residual heal in the condensate should be salvaged. This heat may be salvaged by means of a cooling coil, or as is more frequently done, by a water heating economizer (see Fig. 5) which preheats the hot water supply to the building. Fig. 6 shows a typical steam service installation for high pressure steam, complete for steam flow metering, water heating, preheating, automatic heating control, and for using steam for other purposes. The condensation from the heating system, after leaving the trap, passes through the economizer. The supply to the hot water heater passes through the economizer, ab sorbing heat from the condensate. If the hot water system in the building is of the recirculating type, the recirculating connection should be tied in between the economizer and the water heater proper, not at the economizer inlet, because the recirculated hot water is itself at a high temperature. The number of square feet of heating surface in the economizer should be approximately equal to one per cent of the equivalent square feet of heating surface in the building. Because of the lack of coincidence between the heating system load and the hot water demand, a greater amount of heat can be extracted from the condensate if storage capa city is provided for the preheated water. Frequently a type of economizer is used in which the coils are submerged in a storage tank. S. Heat supply should be graduated according to variations in the outside temperature. This may be done in several ways, as by the use of temperature controls of various types or by orifice systems. Another method which is very simple is the use of an ordi nary vacuum return line system in which the pressure in the radiators is varied between a high vacuum and a few pounds pressure, thus producing some control over the heat output of the heating system by varying the temperature of the steam in the radiators. Several proprietary systems are on the market which accomplish this automatically, either with outdoor or indoor controls or a combination of both. One form of control which appears to be well suited for controlling district steam service to a building is the weather compensating control. It regulates the steam supply automatically ac cording to the outdoor temperature, and gives frequent short intervals of intermittent steam supply, and at the same time insures delivery of steam to all the radiators. This type of control can be equipped with time clocks and thermostats to provide a warmingup period in the morning. Another form of regulation, known as the time-limit control, is sometimes employed for regulating the steam supply from the central station main to the building. Such a control provides an intermittent supply of steam to the radiators either throughout the 24 hours of the day or during the daytime hours only. The setting of a switch may provide no service, continuous service, or periodic service. For the latter, by means of several intermittent settings, steam will be supplied during each period in increments of a certain number of minutes for each successive setting of the switch, steam being shut off during the balance of the period. These settings afford from 15 to 80 per cent of the maximum heating effect required on days of zero temperature. A night switch with a variety of settings may be adjusted so as to maintain throughout the night the inter mittent supply called for by the day switch setting, or may be set to interrupt the opera- 732 733 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 tion of the day switch and entirely cut off the supply of steam to the radiation at night during certain hours which are selected by the operating engineer. The maximum in economical operation and satisfactory heating can only be obtained by the use of some automatic temperature control system. FLUID METERS The perfection of fluid meters has contributed more to the advance ment of district heating than any other one thing. These meters may be classified as follows: X. Positive Meters: The fluid passes in successive isolated quantities--either weights or volumes. These quantities are separated from the stream and isolated by alternately filling and emptying containers of known capacity. 2. Differential Meiers: In the differential meter, the quantity of flow is not determined' by simple counting, as with the positive meter, but is determined from the action of the steam on the primary element. Additional sub-divisions of these two general classifications can be made as follows: Weighing /- --Weigh ers Tilting trap ' Positive - Quantity . Volumetric / Rotary | Bellows Fluid Meters Differential Quantity - Current - Turbine Head (Kinetic) Venturi Flow nozzle Orifice Pitot tube Rate of flow Area (Geometric) f Orifice and plug , \ Cylinder and piston Head area (Weir) ( V-notch \ Special notch In selecting a meter for a particular installation, the number of different makes and types of meters suitable for the job is usually limited by one or more of the following considerations: 1. Its use in a new or an old installation. 2. Method to be used in charging for the service. 3. Location of the meter. 4. Large or small quantity to be measured. 5. Temporary or permanent installation. 6. Cleanliness of the fluid to be measured. 7. Temperature of the fluid to be measured. 8. Accuracy expected. 9. Nature of flow: turbulent, pulsating, or steady. , 10. Cost. (a) Purchase price. (b) Installation cost. (c) Calibration cost. (<) Maintenance cost. 11. Servicing facilities of the manufacturer. 12. Pressure at which fluid is to be metered. 13. Type of record desired as to indicating, recording or totalizing. . 14. Stocking of repair parts. 734 5, CHAPTER 43. DISTRICT HEATING 15. Use of open jets where steam is to be metered. 16. Metering to be done by one meter or by a combination of meters. 17. Use as a check meter. 18. Its facilities for determining or recording information other than flow. Condensation Meters The majority of the meters used by district heating companies in the sale of steam to their customers are condensation meters. The condensation meter is a popular type for use on small and medium sized installations, where all of the condensate can be brought to a com mon point for metering purposes. Its simplicity of design, ease in testing, accuracy at all loads, low cost, and adaptability to low pressure distri bution has made it standard.equipment with many heating companies. Two types of condensation meters are in general use: the tilting bucket meter and the revolving drum or rotor meter of which there are several makes on the market. Condensation meters should not be operated under Fig. 7. Gravity Installation for Condensation Meter Using Vented Receivers pressure; they are made for either gravity or vacuum installation. Con tinuous flow traps are necessary ahead of the meter if a vented receiver is not used. Where bucket traps are used, a vented receiver before the meter is essential. If desirable a receiver may be used with a continuous flow trap, but this is not necessary. Fig. 7 illustrates a gravity installation using a vented receiver ahead of the meter, while Fig. 8 shows a vacuum installation without a master trap. Flow Meters Steam flow meters are available in many types and combinations. The orifice and plug meter is one in which the steam flow varies directly as the area of the orifice. The vertical lift of the plug, which is proportional to the flow, is transmitted by means of a lever to an indicator and to a pencil arm which records the flow on a strip chart. The total flow over a given period is obtained by measuring the area by using a planimeter on the chart and applying the meter constant. Fig. 9 shows a typical orifice-type meter connection and indicates typical requirements in the installation of this type of meter. 735 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Flow meters using an orifice, Venturi tube, flow nozzle, or Pitot tube as the primary device are made by a number of manufacturers and can be obtained in either the mechanically or electrically operated type. The electric flow meter makes it possible to locate the instruments at some distance from the primary element. Flow meters employing the orifice, Venturi tube, flow nozzle or Pitot tube should be so selected as to keep the lower operating range of the load above 20 per cent of the capacity of the meter. This is desirable for accuracy as the differential pressure at light loads is too small to properly actuate the meter. A few general points to be considered in installing a meter of this type are: 1. It is desirable to place the differential medium in a horizontal pipe in preference to a vertical one, where either location is available. CHAPTER 4S. DISTRICT HEATING by using a consumption of 0.0025 lb per day per cubic foot of heated space for office buildings, and 0.0065 lb per day per cubic foot for apartment , houses. Additional data on steam requirements of various types of buildings in a number of cities may be found in the Handbook of the National District lieating Association. RATES Fundamentally, district heating rates are based upon the same princi ples as those recognized in the electric light and power industry, the main object being a reasonable return on the investment. However, there are Fig. 8. Vacuum Condensation Meter Installation without Master Trap 2. Reservoirs should always be on the same level and installed in accordance with the instructions of the meter company. 3. The meter body should be placed at a lower level than that of the pressure differ ential medium. Special instructions are furnished where the meter body is above. 4. Meter piping should be kept free from leaks. 5. Sludge should not be permitted to collect in the meter body. 6. The meter body and meter piping should be kept above freezing temperatures. 7. It is best not to connect a meter body to more than one service. 8. Special instructions are furnished for metering a turbulent or pulsating flow. STEAM REQUIREMENTS Steam requirements for heating various types of buildings are given in Chapter 12. Steam requirements for water heating can be satisfactorily estimated 736 Fig. 9. Orifice Meter Steam Supply Connection other requirements to be met; the rate for each class of service should be based upon the cost to the utility company of the service supplied and upon the value of the service to the consumer, and it must be between these two limits. District heating rates should be designed to produce a sufficient return on the investment regardless of weather conditions, although existing rate schedules do not conform with this principle. Lastly, the rate schedule must be reasonably easy for the intelligent lay man to comprehend. Depreciation should be based on a careful estimate of the life of various elements of the property. Appropriations to reserves should be made, with generosity in good years and with discretion in less favorable years. Glossary of Terms Load Factor. The ratio, in per cent, of the average hourly load to the 737 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 maximum hourly load. This is usually based on a one year period but may be applied to any specified period. Demand. Factor. The relation between the connected radiator surface or required radiator surface and the demand of the particular installation. It varies from 0.25 to 0.3 lb per hour per square foot of surface. Diversity Factor. The ratio of the sum of the individual demands of a number of buildings to the actual composite demand of the group. Types of Rates A. Flat Rates. 1. Radiator surface charge. Obsolescent. B. Meter Rates. 1. Straight-line. 2. Step. Obsolescent. 3. Block. (a) Class rates. C. Demand Rates. 1. Flat demand. 2. Wright. 3. Hopkinson. 4. Doherty (or Three charge) Straight-Line Meter Rate. The price charged per unit is constant, and the consumer pays in direct proportion to his consumption without regard to the difference in costs of supplying the individual customers. Block Meter Rate. The pounds of steam consumed by a customer are divided into blocks of thousands of pounds each, and lower rates are charged for each successive block consumed. This type of charge predominates in steam heating rate schedules for it has the advantage of proportioning the bill according to the consumption and the cost of service. It has the disadvantage of not discriminating between customers having a high load factor (relatively low demand) and those having a low load factor (relatively high demand). The utility company must maintain sufficient capacity to serve the high demand customers and the cost of the increased plant investment is divided equally among the users, so the high demand customers are benefitted at the expense of the others. Demand Rates. These refer to any method of charge based on a measured maximum load during a specified period of time. The flat demand rate is usually expressed in dollars per M lb of demand per month or per annum. It is based on the size of a customer's installation, and is seldom used except where a flow meter is not practicable. The Wright demand rate is similar in calculation to the block rate except that it is expressed in terms of hours' use of the maximum demand. It is seldom used but forms the basis for other forms of rates. The Hopkinson demand rate is divided into two elements: (a) A charge based upon the demand, either estimated or measured. (b) A charge based upon the amount of steam consumed. This rate may be modified by dividing the quantities of steam demanded and consumed into blocks charged for at different rates. The Doherty rate is divided into three elements: (a) A charge based upon demand. (b) A charge based upon steam consumed. (c) A customer charge. In the Hopkinson rate, the last two elements are combined into one element. Demand rates are comparatively new and are not yet widely used; though they are equitable and competitive they are difficult for the average layman to understand. CHAPTER 43. DISTRICT HEATING They are of benefit to utility companies and to consumers because the investment and operating costs can be divided to suit the particular circumstances into demand, cus tomer, and consumption groups through the use of some modification of the Hopkinson rate. Demand rates are an advantage to the customer in that the use of such a rate reduces the rate per thousand pounds to the long-hour user. . Fuel Price Surcharge. It is usually desirable to establish a rate upon a specified basic cost of fuel to the utility company. Where there are wide variations in the price of fuel, it is also desirable to add a definite charge per M lb of steam sold for each increment of increase in the price of fuel. This surcharge automatically compensates for the variations without necessitating frequent changing of the whole rate structure. UTILIZATION Considerable savings can be made by the proper and intelligent oper ation of heating systems. It should be borne in mind that a heating system is designed to heat a building to 70 F inside when the outside temperature is at its lowest point for that particular locality. There is a tendency to overheat the building at any time the outside temperature is above the design temperature unless some method of regulation is used, either automatic or manual. The general rules for economical operation are as follows: 1. Weatherstrip all windows, and calk all window frames. 2. Provide revolving or vestibule doors on all entrances. Separate shipping and receiving rooms by partitions so that the ever-open large doors will not ventilate the entire building. 3. Keep the radiation near the outside walls, under the windows, if possible. 4. Eliminate all unnecessary ventilation. Ventilating equipment is sized to meet extreme requirements. Do not supply ventilation to a theater or auditorium adequate for an audience of 2000 when there are only 200 present. 5. Determine the hours that heating is required during the day and see that the steam is shut off for the maximum time at night, on Sundays, and holidays. 6. Shut steam off entirely in unoccupied sections of the building, taking care to avoid freezing the water in the plumbing system. 7. Shut off steam during the day whenever possible. During the year steam can be shut off about 55 per cent of the total daytime, the saving is proportional. An automatic control will do it, but it can be done by hand with amazingly good results. 8. Determine the temperature required for the occupancy of the building. Do not heat a storage garage or a furniture warehouse to the temperature required in a hospital ward. 9. Provide some good means of temperature control. 10. In a hot water heating system keep the temperature of the water down to corre spond with existing outdoor temperatures. 11. In a vacuum system maintain a high vacuum. If this is not possible, locate and eliminate all leaks. ' 12. Install separate lines for those parts of the building that require long-hour or all-night heating. It is much cheaper than heating the entire building ail night. 13. See that the entire system responds rapidly when steam is turned on. Locate and eliminate the cause of any sluggish circulation. Balance the radiation, provide adequate air elimination, and correct any trapped run-outs to provide quick system drainage. 14. Keep the system in good repair. Worn, damaged, or defective valves and traps will not function properly. 15. Insulate all steam pipes not used as heating surface. 16. Do not obstruct radiators or prevent the free circulation of air around them; to do so seriously reduces the heating capacity of a radiator. 17. Extract the heat in the condensate for hot water or some other useful purpose. 18. Provide thermometers and recording pressure gages so that the engineer can operate the system with full knowledge of what he is accomplishing. 739 HEATING VENTHATING AIR CONDITIONING GUIDE 1940 19. Make all valves and controls convenient and accessible, either direct or through remote control. It is only human nature to delay and avoid doing that which is incon venient. 20. Keep a daily record consistently, based on weather requirements, and watch it every day. 21. Control the heat supplied to water tanks located on or above the roof. Such tanks require heat to prevent freezing. No heat is required when the temperature in the tank is above 32 F. - : 22. Investigate every complaint of no heat by tenants; find the cause and correct it. Do not overheat an entire building to correct a local condition in one room. ' AUTOMATIC TEMPERATURE CONTROL As stated in Chapter 38, Automatic Control, properly applied to heating, ventilating and air conditioning systems makes possible.the maintenance of desired conditions with maximum operating economy, ;: In addition to the large possibilities for economy, the use of adequate temperature control provides more healthful, comfortable, and efficient working conditions in the buildings because through its use the building is uniformly heated with correct temperatures and drafts, from open windows and overheating are eliminated. . There are many types of temperature control available, each adaptable to a particular,type-of building, but all require uniform distribution of steam and proper venting. Before the installation of any type of modern temperature control equipment, it is necessary to see that the heating system is put in good operating condition. In general, the heating system in a building is not given the attention that other mechanical equipment is given because it will continue to function, after a fashion, even though changes in piping,, location of radiation, settlement of piping, and the normal wear and tear, or other changes have taken place. Through all this depreciation of the. system, it becomes more and more costly to operate and parts of the building have to be greatly overheated in order tq_prevent underheating in a small section of the building. Vents, traps, vacuum :pumps, and valves should be given a careful inspection and replaced or repaired if required. The piping should be of adequate size and graded properly. The return piping should have a careful inspection, and any. pockets or lifts removed and properly vented. These, inspections and repairs are not costly and prevent a much greater outlay in future years. In most cities district heating companies will be willing to make a survey of heating systems and offer recommendations-as to operation and changes in piping ' layout. The selection of control equipment depends upon the type and size of building and the degree of saving possible. v Chapter 44 WATER SUPPLY PIPING AND WATER HEATING Maximum Possible Flow, Maximum Probable Flow, Average . . Probable Flow, Factor of Usage,. Kind of Pipe Used, Sizing of ' ' Risers, Sizing of Mains, Sizing of Systems, Hot Water Supply, Hot Water Heating, Hot Water Storage, Swimming Pool Heat, mg Requirements ' DOMESTIC water supply systems present the engineer with a design problem that requires combining the somewhat empirical rules and formulae in use with the more or less `exact hydraulic principles involved. Unlike heating and ventilating layouts, there are practically no definite data for estimating the quantity of water likely to be consumed or the probable rate of water flow at any particular moment. Metered results in one building often show two or three times the metered amount in another building of the same size and with the same type.of tenants. In hotels, one riser will often have an almost constant flow that may never be reached by another at peak load. In office buildings, the women's toilets show a far greater daily consumption than those of the men, yet at no time will they approach the hourly consump tion of the men's toilet during the first hour of the day. This condition has led to, a multiplicity of rules of practice which vary as much as the data usedKiAAll must of necessity be based on an assumed rate of con sumption and oh an assumed probability of simultaneous use, and while the formula employed may have been derived on sound technical basis the assumptions are often in error. . To arrive at a safe standard, the approximate rate of flow of each fixture to be supplied must be known and the probable number of fixtures in use at any one time must be assumed. Obviously, the maximum number of fixtures assumed to be in use must be taken at the peak of demand and the lines must be made adequate to supply such a peak regardless of the riser or branch on which the demand may occur. This means that all water piping under the usual-conditions will be over-sized. In tall buildings it is customary to divide the water supply systems, both hot and cold, into sections of 10 to 20 stories. Such zoning1 or `It Is impractical to attempt to size piping so as to produce the proper pressure on fixtures at different levels by employing friction, owing to the fact that this friction will bebuilt up to the amount desired only in times of maximum demand and at all other times the friction will.be only a fraction of the maximum friction so that the fixtures by this method are subjected to a varying pressure on the water supply line. A much more practical method is to throttle the flow at the fixture, or to use flow regulators, so that the quantity of water delivered will approximate the fixture demands and so that this is accomplished without splashing or noise. ' 741 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 sectionalizing is for the purpose of avoiding excessive pressures on the fixtures in the lower stories of each system. This limits the consideration of water pipe sizes to horizontal mains and to risers not exceeding 20 stories in height or about 200 ft. For the purpose of this chapter the following terms will be used and should be dearly distinguished from one another: . Maximum Possible Flow: The flow which would occur if the outlets on all fixtures were opened simultaneously. This condition is seldom, if ever, obtained in actual practice ex cept in cases of gang showers controlled from one common valve, and similar conditions. Maximum Probable Flow: The maximum flow which any pipe is likely to carry under the peak conditions. This is the most important amount to be considered in pipe sizing. Average Probable Flow: The flow likely to be required through the line under normal conditions. It is evident that any pipe adequate to take care of the maximum .100 .80 I- fl\ U this curve for m xe 1 systerns with ush vaIves am ordi la ry fixtures i 40 n S 20 Uset itectirv ifiX P ha\ mg no lus h va ve fixtures Fig. 1. MAXIMUM POSSIBLE FLOW GPM Chart Showing Relation Between Maximum Possible Flow and Maximum Probable Percentage of Use probable flow will also be more than able to take care of the average probable flow, and hence the latter has no bearing on the pipe size. MAXIMUM PROBABLE FLOW There are two factors to be considered in calculating the maximum probable flow, namely, (1) the quantity of water that will flow from the outlets when they are open, and (2) the number of outlets likely to be open at the same time. Table 1 shows the maximum approximate rate of flow from each fixture when it is in use, and will serve as a guide in estimating maximum probable flow demands although there is considerable variation in different fixtures and valves. Probably the flow under normal water pressures, or with the pressure properly throttled, will not differ greatly from the values stated. With the aid of this table it is possible to calculate the maximum possible flow with.all outlets open in both the hot and cold water lines. 742 T--^ CHAPTER 44. WATER SUPPLY PIPINC AND WATER HEATING To obtain the maximum probable flow it is necessary to multiply the maximum possible flow by a factor of usage, and this factor varies with the installation and the number of fixtures in the installation. It is evident ' that with two fixtures it is quite possible that both will at some time be in operation simultaneously. With 200 fixtures, it is unlikely the entire 200 would ever operate at the same time. Consequently, the factor of usage reduces as the number of fixtures becomes greater, all other things being equal. ' Table 1. Approximate Flow from Fixtures Under Normal Water Pressures Fixtures Water-closets, flush valve.............................. Water-closets, flush tank................................ Urinals, flush valve....................................i.......................... Urinals, flush tank. ......... :............................................. Urinals, automatic tank_________ _____ _______ Urinals, perforated pipe per foot____ :........... Lavatories____ __________ ______ .._______ Showers, 4 in. heads, H in- inlets............... Showers. 6 in. heads or larger...................... Needle bath___ _______i.......... ................. Shampoo spray... - ......................................... Liver spray........ .......... ............. ;...................... Manicure table..... ............ ............................... Baths, tub... ................................................ Kitchen sink................................................... Pantry sink, ordinary..............;.................... Pantry sink, large bibb................................. Slop sinks... ..................................... .. Wash trays..... ................................................. Laundry trav...................... ......... Garden hose bibb............... Cold Water (Gallons per Minute) . 45a 10 30 10 1 10 3 3 6 30 1 9 114 5 4 2 6 6 3 6 10 Hot Water (Gallons per Minute) 0 0 0 0 0 0 3 3 6 30 1 2 1 X4 5 2 6 0 Actual tests on water-closet flush valves indicate 40 gpm as the maximum rate of flow with 30 lb pres sure at the valve; this would increase to 60 gpm (about 50 per cent) at 90 lb pressure. The 45 gpm has been taken as an average flow; possibly, with very low pressures just sufficient to operate the flush valve. 30 gpm could be allowed with safety. Urinal flush valves would vary proportionately in the same manner. In practice all the elements will vary according to conditions; in the case of flush valve closets the duration of flush with the kind and condition of supply apparatus, the interval between flushes with the number of people using the system and their habits; and the length of the rush period with the type of installation and its location. The effect of each of these time elements on the results should be considered in connection with any data on which it is based before passing judgment on the selection of the factor of usage. The longer the duration of the flush the greater is the probability of overlapping flow. In selecting the factor of usage shown in Fig. 1 for systems having flush valves, 10 seconds was chosen as the maximum duration of flush, a value that represents an approximate average as water-closets are installed. While the curve has been calculated for systems composed of water: closets alone, it is possible to calculate probabilities for mixed systems of water closets and other smaller fixtures. It has; been found however that for two systems both having the same maximum possible flow, one com posed entirely of water-closets and the other a mixed system of water . 743 . T a b le 2. Schedule of Sizes for D own-F eed R iser (See F ig . 2) HEATING VENTILATING AIR CONDITIONING CUIDE 1940 closets and smaller fixtures, the probability of a- given rate of flow is greater for the system composed of water-closets than for the mixed system. The use of .this chart then would produce results which would be on the safe side for mixed systems. . For systems composed entirely of fixtures other than flush valve fixtures the curve has been extended for smaller maximum possible Bow values. 744 CHAPTER 44. WATER SUPPLY PIPING AND WATER HEATINC . This chart applies to a normal building and not to installations where the inmates may all be required, for instance to bathe on certain days of the week and at certain, hours of those days; or in schools for example where alt the showers in the gymnasium may be used simultaneously after instruction periods. In such special cases a new factor of usage must be developed based on the maximum probable usage under the conditions involved. Example 1. Assume that in a normal building, such as a residential hotel or an apart ment bouse, there are 50 flush valve water-closets, 50 lavatories, 50 sinks and 50 baths, and that it is desired to determine the maximum probable flow in a line supplying all of these fixtures with both hot and cold water. CoW Water .. 50 W. C. x 45 gpm__ ._____ 2250 gpm 50 Lavs, x 3 gpm_________ 150 gpm 50 Sinks, x 4 gpm 200 gpm 50 Baths x 5 gpm__ ______ 250 gpm . Maximum possible flow.__ 2850 gpm Fig. 1 shows a factor of usage of 9'per cent. "Maximum probable flow of cold water is 2850 X 0.09_______ 257 Hat Water .50 Lavs, x 3 gpm______ 150 gpm 1 50Sinks x 4 gpm___ ,____ 200 gpm 50 Baths x 5 gpm_______ 250 gpm Maximum possible 600 gpm Big. 1 shows a factor of - usage of 23 per cent. Maximum probable flow of hot water is 600 X 0.23138 gpm Total for main supplying cold and hot water (2850 + 600) X 0.08--____________ 276 gpm It should be noted that this is a rate offlow or an instantaneous demand. KIND OF PIPE USED Before entering into the actual sizing of pipe, it is necessary to consider the kind of pipe to be used, and to make suitable allowance for corrosion and fouling during the lifetime of the system. For example, if brass, copper or alloy pipe is contemplated, it is probable that the quantities indicated in Example 1 are ample; if galvanized pipe is to be used, then it is quite likely that after a period of say 15 years the area may be decreased as much as 25 per cent and the quantitities of water assumed should be increased by 35 per cent to allow for this reduction of area; if the water contains lime it is-possible that 50 per cent of the area may be lost and in such cases the flow should be doubled and no branch pipe connected to fixtures should be less than % in. In all of the following calculations, the assumption is made , that the .water is fairly good and that a corrosion resistant type of pipe is to be used. SIZING A DOWN-FEED RISER Down-feed systems are commonly used for tall buildings. In sizing a riser arranged for down-feed, the gravity head permits a pressure drop that is almost prohibitive in an up-feed riser. There is a gain in riser head of 0.43 X 100 or 43 lb per 100 ft of run and hence it is quite permissible to size such a riser on the basis of a pressure drop of.30 lb per 100 ft of run, as the difference between the 43 lb generated and the 30 lb drop under ` maximum probable demand is ample to take care of the friction caused by the fittings. This, method applied to the typical riser shown in Fig. 2 gives the schedule of sizes indicated in Table 2 for any flow from 5 to 250 gal. HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 SIZING AN UP-FEED RISER When the riser is an up-feed, the opposite condition occurs; that is, there is a drop in pressure as the top of the riser is approached, due to the natural reduction in the gravity pressure, and to this must be added, the pipe friction plus that introduced by the pipe fittings, all of which produce an excessive drop when compared to the conditions existing with a downfeed riser. To size an up-feed riser the minimum pressure of the street main, or other source of supply, should be ascertained and from this should be subtracted the pressure to be maintained at the highest fixture, namely, 15 lb per square inch, plus the height in feet above the source of water pressure, multiplied by 0.43 to change from feet of head to pounds of pressure. The total length of run from the source of pressure to the farthest and highest fixture should be ascertained, and this should be changed to equivalent length of run to allow for the loss occasioned by Table 3. Approximate Allowances for Fittings and Valves in Feet of Straight Pipe or Pips (Inches) h H 1 m ni 2 m 3 4 5 6 90-Deg Elbow 4 5 5 6 7 7 10 12 18 25 30 45-Deg Elbow 3 3 3 4 5 5 7 8 13 18 21 Ttfb or. Fitting oa Vaxvb Return Bend Gate Valve 82 10 3 10 3 12 3 14 4 14 4 20 5 24 6 36 9 50 13 60 15 Globe Valve 48 60 60 72 84 84 120 144 216 300 360 ' Angle Valve 8 10 10 12 14 14 20 24 36 50 60 the pipe fittings. Table 3 gives the additional lengths necessary to allow for the various fittings and valves. The drop allowable in pressure per 100 ft of run may then be obtained by multiplying the surplus pressure (over that required for the gravity head and to supply 15 lb at the fixture) by 100 and by dividing this by the equivalent length of run to the farthest or highest fixture. Where street water pressures are available the pressure drop through the meter and service pipe must be taken into consideration. Table 4 shows the pressure loss through meters. It also gives the minimum sizes of recommended service and maximum meter deliveries. Example 8. Assume a street pressure of 60 lb, the height of the highest fixture SO ft, and the length of the longest run 200 ft. Without knowing the additional length of pipe to be added for the fittings it will be assumed that this is about 100 ft. The surplus pressure which will be available for pressure drop will then be 60 lb -- (15 lb + 50 ft X 0.43 lb) = 60 lb - (15 lb + 21.5 lb) = 23.5 lb. To change this into drop per 100 ft: 200'*ft ^f^lOO^t = per ^ The pipe may then be sized from the maximum probable flow by selecting a size that does not give a drop in excess of 7.8 lb per 100 ft. 746 It will be seen from Example 2 that it is impossible to size up-feed risers without determining the drop allowable in both the horizontal feed mains and the toilet room branches. Having once ascertained this allow able drop, it is simply a matter of applying it throughout the system. 4. Loss. Table. Pressure Through Water Disc Meters4 . A. W. W. A. Standards ' 747 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 ; HORIZONTAL SUPPLY MAINS The horizontal mains supplying the risers at the top of a down-feed system must be liberally sized unless the house tank is set at a much higher elevation' than usual:' To provide a gravity head on the highest fixtures of 15 lb per square inch it is necessary for the water line in the house tank to be nearly 40 ft higher, and with the line loss considered this, becomes about 45 ft. Such heights are not often practical and as a result the pressure on the highest fixtures either is reduced to 7 lb (which is sufficient to operate a flush, valve), or flush tank water-closets are: sub stituted, or a separate cold and hot water supply is installed with a small pneumatic tank to give the increase in pressure necessary. The chief objection to' the use of a pneumatic tank is that a separate hot water heater is required and this heater must be located either sufficiently below the highest fixtures to obtain a gravity circulation, of it must be provided with a circulating pump in order to force the hot water to the top floor level. : The most common solution is to place the house tank as high as the structural and architectural conditions will permit and then to use liberally-sized lines between the house tank and the upper fixtures, say for the two top stories, below which the riser sizes may be reduced to those indicated in Fig. 2 and Table 2. Where the house tank is only One story above the top fixtures, flush tank water-closets must be used and the drop in the entire run from the house tank down to the farthest fixture should not exceed 1 lb; the less, the better. This means that if the total equivalent run to the farthest top fixtures supplied is 300 ft, the drop per 100 ft should not exceed * ^ ^ or 0.33 15 per 100 ft. The friction curves shown in Fig. 3 may be used for quickly determining the proper size of pipe to give any desired drop in pounds per 100 ft of equivalent run. OVERHEAD DISTRIBUTION MAIN Example 3. Suppose an installation has a house tank in which the water line is'20 ft above the level of the top fixtures to be supplied and that the length of run to the' farthest fixtures on this level is 400 ft with the pipe fittings adding another 200 ft, making an equivalent length of 600 ft. What would be the size of main, coming out of the tank where a maximum flow rate of 400 gpm may be expected, of the horizontal main where a maximum flow rate'of 200 gpm may be expected, and of the riser down to the fixture level where the maximum flow rate is approximately 100 gpm? Here the level of the water in the house tank is 20 ft above the faucet of the highest fixture and the gravity pressure will be 0.43 lb X 20 ft = 8.6 lb and, if a total pressure drop of 1 lb is assumed, the pressure on the farthest fixture under times of peak load will be 8.6 lb -- 1 lb = 7.6 lb while the drop per 100 ft of equivalent run will have to be 1 lb X 100 = 0.16671b. 600 Referring to Fig. 3 it will be noted that where the flow through the main is 400 gpm, an 8-in. pipe would be required; that where the flow is reduced to 200 gpm, a 6-in. pipe would be sufficient; and that where the flow is 100, gpm in the riser branch and riser, a 5-in. size would be correct. Of course these are somewhat excessive flows and the head from the tank is small so that large sizes are to be expected. It would be necessary to carry a 5-in. riser down to the branch to the top floor, then reduce to 4 in. for the branch to the floor below the top, and below this the sizes in Table 2 could be followed. In such a case, flush tank closets should doubtless be substituted. Had the tank been set 10 ft higher, the head available to be used up in friction, but 748 CHAPTER 44. WATER SUPPLY PIPlNC AND WATER HEATING DVU`l 1 TMpressure at tne top fixtures, would have been 0.43 lb X 10 ft or 4.3 lb tI|tftxra 5 m thMlb.<?r?P ""d previously, would give a total allowable drop of 1 vino- 5-3 b wb,cb'dlvlded by the 600 ft equivalent run gives a drop per 100 ft of = ^*b 749 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Fig. 4. Typical Layout for Down-Feed System House Tank-]'' House Supply Fire Reserve __ i_ ' 197 197 4* |^ 8th. 4W.C.-F.V. 2U.-F.V. 3 Lav. _ 4W.C.-F.V. 166 t 2U.-F.V. 7th. w. 3Uv- . 145 2 6th. ' 4W.C.-F.V. 2U.-F.V. 3 Lav. . 117 2 5th. 4W.C.-F.V. 2U.-F.V. 3tav- 25 T 4th. 10 Lav. 11 f 1S.S. 2nd. 8 f 1S.S. - . 4 f .1S. S. 4' 255 215 4- 6W.C.-F.V. 4 Lav. ,,,, 211 2f 2 6W.C.-F.V. 4 Lav. 196 2f 6W.C.-F.V. 4 Lav. 180 2" 6W.C.-F.V. 4 Lav. . 160 2 4W.C.-F.V. 2 U.-J\ V. 3 Lav. . 130 2 4W.C.-F.V. 2U.-F.V. 3 Lav. 2W.C.-F.V. ' 98 li 1U.-F.V. 1 Lav. 45 It 1W.C.-F.V. 5' (I) (2) 122 ri i s. s. A 12J 2 1S. S. . 120 2" 1SS. 120 2' 1 S. S. - 3 W.C.-F.V. 2" 1 Lav. , > 1 S.S. 90 2" 2 Lav. ,r 3W.C.-F.V. 2 1 Lav. 4 * 1S.S. *-9C ... (3) and, with this drop, the sizes according to the chart (Fig. 3) are 6 in., 5 in., and 4 in., respectively, while if the run is reduced to 200 ft instead of 600 ft, the allowable drop will be 5-3 100 = 2-7 pet 100 ft- This gives 5 in., 4 in., and 3 in., respectively, for the flows of 400, 200, and 100 gpm. , From Example 3 it is evident that, while the down-feed system possesses certain economies in size for the riser portion, it is quite likely to involve large distribution main sizes, especially when the tank is not elevated to a considerable degree. SIZING A PIPING SYSTEM Example 4. Fig. 4 shows a typical layout with three risers extending eight stories and with the fixtures noted on each floor. First this will be solved for a down-feed arrange ment assuming that the level of the water in.the house tank is 30 ft above the fixtures on the top floor, that the length of run from the tank to the farthest fixture is 200 ft, equiva lent length of fittings 100 ft, and the pressure required at the fixture is 7 lb. 750 CHAPTER 44. WATER SUPPLY PIPINC AND WATER HEATINC Table 5. Typical Calculation of Pipe Sizes on Down-Feed Riser with Flush Valve Water-Closets and Urinals (Riser No. 1. Fig. 4) Floor of Bldg. Fixtures on Floor 1st 1 S. S. 2nd ' 1 S. S. 3rd 1 S. S. 4th 10 Lav. 5th 4 W. C. 2 U. 3 Lav. 6th 4 W. C. 2 U. 3 Lav. 7th 4 W. C. 2 U. 3 Lav. 8th 4 W. C. 2U. 3 Lav. Gpm PER Fixture 4 4 4 3 45 30 3 45 30 3 45 30 3 45 30 3 Maximum Gpm ON Floor Maximum Gpm on Riser Probable USB (per cent) Probable Demand Riser Gpm Allowable Drop Lb per 100 Ft 4 4 100 4 30 4 S 100 8 30 4 12 92 11 30 30 42 58 25 30 180 60 9 249 291 40 117 30 180 60 9 249 540 27 145 30 180 60 9 249 789 21 166 30 180 60 9 249 1038 19 197 2 Pipe Size In. H H H 1 2 2 2 4 The 30-ft head is equal to a static pressure of 0.43 X 30 or 12.9 lb per square inch and to maintain a pressure of 7 lb at the highest fixtures the drop allowable in pressure is 12.9 -- 7.0 lb/Jr 5.9 lb. As the total equivalent run is 300 ft, this is a drop per 100 ft of 1.97 lb, or practically, 2 lb. Therefore, all risers and mains from the top floor back to the tank must be sized on the basis of a drop of 2 lb per 100 ft. Tables 5, 6, 7 and 8 show the schedule for Risers Nos. 1, 2 and 3 with the maximum possible flow taken from Table 1, the percentage of use at the peak taken from Fig. 1, and the maximum probable flow at the peak worked out for each portion of the riser, the riser sizes being taken from Table 2 as far as possible and from Fig. 3 where the amounts exceed the values given in this table; a drop of 30 lb per 100 ft is used except on the riser from the top floor back to the tank where 2 lb per 100 ft is the allowable limit. The reduction in pipe size which would occur if flush tank water-closets were used on the top floor and only 3 lb pressure used on the fixtures is given in Tables 9 and 10. This illustrates why flush tank closets so-frequently are substituted on the uppermost floor when a house tank is the source of water pressure. If it is now assumed that Riser No. 1 is to be fed from the bottom and the minimum street pressure is 75 lb with the top fixture of the riser 80 ft above the main, the problem would be solved by determining the maximum rate of flow in each portion of the riser as shown in Table 11 and then finding the allowable drop which can be used per 100 ft. The 80 ft of riser height will use up 0.43 lb X 80 = 34.4 lb and the pressure at the top of the required 15 lb will make the total reduction 49.4 lb, leaving a balance of 25.6 lb which may be used up in friction. If the distance from the street main to the bottom of the riser, which will be assumed to be the farthest one on the horizontal line, is 100 ft, and if the fittings are sufficient to add another 100 ft, as well as the 80 ft of vertical distance up the riser, the total equivalent run will be 280 ft, which will be taken as an even 300 ft. 751 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Table 6. Typical Calculation of Pipe Sizes on Down-Feed Rises with Flush Valve Water-Closets and Urinals (Riser No. 8. Fig. 4) Floor op Bldg. 1st 2nd 3rd 4th 6th 6th 7th Sth Fixtures on Floor 1 W. C. 2 W. C. 1 u. 1 Lav. 4 W. C. 2 U. 3 Lav. 4 W. C. 2 U. 3 Lav. 6 W. C. 4 Lav. 6 W. C. 4 Lav. 6 W. C. 4 Lav. 6 W. C. 4 Lav. Gpm PER Fixture 45 45 30 3 45 30 3 . 45 30 3 45 3 45 3 45 3 45 3 Maximum Gpm on Floor Maximum Gpm on Riser Probable Use (pSR CENT) Probable Demand Riser Gpm Allowable Drop Lb per 100 Ft 45 45 100 45 30 . 90 30 3 123 168 58 98 30 180 60 9 249 417 31 130 30 180 60 9 249 666 24 160 30 270 12 282 948 19 180 30 270 12 282 1230 .16 196 30 270 12 282 1512 14 211 30 270 12 282 1794 12 215 2 Pipe Size In. ia lX 2 2 2 x' ZX 2M 4 4 op / |L y 100 ' Then the allowable drop per 100 ft will be --:---------- = 8.5 lb and the sizes shown , . OvU ... . in Fig. 5 are based on this amount of drop. Of course the other risers will have the same maximum flows at the bottom as they formerly had at the top, namely 215 and 122 gal, respectively, for Risers Nos. 2 and 3. Combining these maximum flows in the same man ner as piirsued in.thedown-feed system it is seen that the maximum flow between Riser No. 2.and Riser No. 3 is 255 gpm, and between Riser No. 3 and the street main, 282 gpm which at a'drop of 8.5 lb gives the main sizes indicated. It will be noted that in determin ing the maximum flow in an up-feed riser it is necessary to begin at the top floor and work down instead of beginning at the bottom floor and working up as was done in the down-feed sizing. SIZING UP-FEED AND DOWN-FEED HOT WATER SYSTEMS Hot water supply systems, when of the circulating type, have a few differences to be considered although the same general principles of sizing apply to these lines as to the cold water lines. Owing to the fact that there are no flush valves on the hot water piping and also because many plumbing fixtures have no hot water connections, the sizes of the hot water piping in general will be considerably less than the cold water piping in the same building. On the other hand it is almost invariably 752 CHAPTER 44. WATER SUPPLY PIPING AND WATER HEATINC Table 7. Typical Calculation of Pipe. Sizes on Down-Feed Riser with Flush Valve Water-Closets and Urinals (Riser No. 8. Fig. 4) Floor , Fixtures of on Bldg. Floor 1st 1 S. S. 2nd 3 W. C. 1 Lav. 3rd 2 Lav. 4th 3 W. C. 1 Lav. 1 s. a 6th 1 S. S. 6th 1 S. S. 7th 1 S. S. 8th 1 S. S. Gpm per Fixture 4 45 3 .3 45 3 4 4 4 4 4 Maximum Gpm on Floor 4 Maximum Gpm ON Riser Probable Use (per cent) Probable Demand Riser Gpm 4 100 4 Allowable Drop Lb per 100 Ft 30 135 3 138 142 63 89 30 -6 148 61 90 30 135 3 4 142 290 41 4 294 41 4 298 40 4 302 40 4 306 40 119 120 120 121 122 30 30 30 30 2 Pipe Size In. H IX IX 2 2 2 2 3 required that a gravity circulation be kept up in such hot water lines and this often has a considerable influence on the size. There are three methods of arranging circulation lines, as follows: 1. By using the plain up-feed with a return carried back from the top of the riser and paralleling it. 2. By carrying a supply riser up in one location thus supplying fixtures on up-feed, then crossing over at the top and coming down past another collection of fixtures and supplying these by a down-feed. 3. By carding all of the water to the top of the building and dropping risers wherever needed, feeding all hot water on a down-feed system. Table 8. Size of Distribution Main for Down-Feed Systems (See Fig. 4) Riser No. 1 2 3 Maximum Gpm Riser 1038 1794 306 Maximum Gpm Main 1038 2832 3138 Probable Use (per cent) 18 9 9 Probable Gpm 187 255 282 Allowable Drop Lb per 100 Ft 2 2 2 Size of Main In. 4 4 -5 In the first instance the up-feed riser may be sized for the same pressure drop as used for the cold water riser and, from the top of the riser just below the top fixture connection, a return circulation line may be carried back to the main return line in the basement and connected through a check valve, set on a 45-deg angle, and a gate valve; these return circu lation lines should never be less than % in., and on the farther half of the risers, not less than 1 in. to favor circulation in the far end. Typical top and bottom connections for such risers are shown in Fig. 6. 753 T HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 Table 9. Typical Calculation of Pipe Sizes on Down-Feed Risers with Flush Tank Water-Closets and Urinals on Top Floor Only (See Fig. 4) Floor of Bldg. Fixtures on Floor Gpm PER Fixture Maximum Gpm on Floor Maximum Gpm ON Riser Probable Use (per cent) Probable Demand Riser Gpm Allowable Drop Lb per 100 Ft Pipe Size In. 7th and below 8th 4 W. C. 2 U. 3 Lav. 10 10 3 Riser No. 1 7S9 40 20 9 69 858 21 20 166 172 30 2 3.3 4 7th and below 8th 6 w. C. 4 Lav. 10 3 Riser No. 2 1512 60 12 72 1594 14 211 LI . 223 30 3.3 2K 4 7th and below 8th 1 S. s. 4 Riser No. S 302 4 306 40 40 121 122 30 3.3 2 3 For the second arrangement of hot water risers (Fig. 7b), circulation lines are run back from the last fixture supplied to the main return circulation line in the same manner as just described, using % in. for the near risers and 1 in. for the far risers. The sizing is much more difficult, as it is necessary to start at the bottom floor of the return riser and work back to the top of this riser and then carry the maximum flow across on to the top of the corresponding supply riser and work down on this riser from the top floor to the bottom. Naturally this gives a much greater flow in the supply riser and aids circulation by reducing pipe friction. The allowable loss per 100 ft in such lines must be made about half that used for the cold water risers which do not have the combined up- and down-travel which the hot water must make. In the third and most common arrangement (Fig. 7c) all of the water is car ried from the tank or heater directly to the top of the.building and is there distributed to the risers which are down-feed' and may be sized in the ; Table 10. Summary of Riser Sizes to Given Main Sizes with Flush Tank Water-Closets and Urinals on Top Floor Only (See Fig. 4) Riser No. 1 2 3 Maximum Gpm Riser 858 1594 306 Maximum Gpm Main 858 2452 2758 Probable Use (per cent) 20 10 9 Probable Gpm 172 245 248 Allowable Drop Lb per 100 Ft 3.3 3.3 3.3 Size of Main In. 4 4 4 754 CHAPTER 44. WATER SUPPLY PIPING AND WATER HEATINC regular down-feed manner if the total equivalent run either from the street main or house tank is taken into consideration. The return circulation lines from the bottom of each riser should be arranged in the majiner already outlined and any riser not going to the basement to supply fixtures must have these returns carried down to the basement from the termination of the supply riser at whatever level it may end. 4W.C.-F.V. | 2U.-F.V. 3 Lav. 8th. 4 W.C.-F V. 2U.-FV. ' * 3 Lav. 7th. 4W. C.-F.V. 2j 2U.-F.V. 6th. 3 Lav. 4 W. C.-F. V. 3* 2U.-F.V. ' x 3 Lav. 5th. T 10 Lav. 4th. 3" is. a 3rd. 3" 1 S. S. 2nd. 3* 1S.S. 1st f 3* Main (I) Fig. 5. Up-Feed System Fig. 6. Supply and Return -Main Connections for Hot Water Supply System All risers, both hot and cold, should be valved at the main with an extra check valve on the hot water return circulation so that the risers may be cut off and repaired when necessary without disturbing the service in the remainder of the system. HOT WATER SUPPLY Having designed the service hot water piping, the next step is to furnish some means of heating the water and in this respect it is necessary to pass from the maximum probable flow to the maximum probable hourly demand, which is quite different. If an instantaneous heater were used, it. would require adequate capacity to provide for the heating of the water as fast as it is drawn and a heater of this type should be sized on the basis of the maximum probable flow with the accompanying heavy drafts on the heating device and with intervals of no draft at all. To balance these inequalities of flow the storage-type heater is often utilized so that the 755 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Table 11. Typical Calculation of Pipe Sizes on Up-Feed Riser with Flush Valve Water-Closets and Urinals (See Fig. S) Floor op Bldg. 8th 7th 6th 5th 4th 3rd 2nd 1st Fixtures on Floor 4 W. C. 2 U. 3 Lav. 4 W. C. 2 U. 3 Lav. 4 W. C. 2 U. 3 Lav. 4 W. C. 2 U. 3 Lav. 10 Lav. 1 S. S. I S. S. 1 S. S. Gpm PER Fixture 45 30 3 45 30 3 45 30 3 45 30 3 3 4 4 4 Maximum Gpm on Floor Maximum Gpm on Riser PROBABLE Use (per cent) Probable Demand Riser Gpm Allowable Drop Lb per 100 Ft 180 60 9 249 249 44 109 8.5 180 60 9 249 498 28 139 8.5 180 60 9 249 747 22 164 8.5 180 60 9 249 996 30 1026 18 179 18 185 8.5 8.5 4 1030 18 186 8.5 4 1034 18 187 8.5 4 1038 IS 188 8.5 Pipe Size In. m 2M 3 3 3 3 3 3 Table 12. Suggested Storage Tank Sizes for Homes and Apartments All Year Service I Service Dubujct Heating Season Based on Boiler Water at 180 F | Based on Boiler Water at 215 F Tank Capacity 30 35 40 50 60 72 80 100 125 150 200 250 300 400 500 Piping Connections Boiler, In. i IK IK IK IK 2 2 2 2 2 2K 2K 3 3 Tank, In. K K K K l l l IK IK IK IK IK IK 2 2 Number o! Baths or Families Tank Capacity i i 1-2 1-2 1-2 2-3 2-3 3-4 4-5 5-6 6-7 7-9 9-11 11-15 15-18 , 30 40 52 66 82 100 120 144 160 200 250 300 400 500 600 Piping Connections Boiler, In. i i i IK IK IK IK IK 2 2 2 2 2K 2K 3 Tank, In. K K K l l l l l IK IK iK IK 2 2 2K Number o! Baths or Families i i 1 1-2 2-3 3 4 5 6 6-7 7-9 9-11 11-15 ih--18 18-21 756 CHAPTER 44. WATER SUPPLY PIPING AND WATER HEATING water demand can be heated during periods of light demand and stored up for use during the periods of heavy demand. The total water con sumption per person usually varies between 100 and 150 gal per day when laundry and culinary operations for the occupants are carried out on the same premises. The maximum hourly demand under these conditions will be found to be about one-tenth of the average daily consumption. If one-third of the total water used is hot water arid 125 gal per day is assumed as a fair average of consumption per person, it is apparent that each person uses about 40 gal of hot water per day. If one-tenth of this represents the peak hourly load', then 4 gph must be allowed per person for the heaviest demand. If the average occupancy of apartments is 3 persons, the peak hour demand per apartment will be about 12 gph. It is customary to allow 10 gph of heating capacity per apartment. Water in excess of this heating capacity drawn out during the peak hours is Vent ' J - a 19 "w c 1* . * a 2 y 1Z >> a. o. s C/5 y. iI o. Ok 9 </) -* I o. W9 * i^ J _ I^ \ i h. 1 H. \ + 1 / Jf * *s a? /of (C) Fig. 7. Methods of Arranging Hot Water Circulation Lines provided for by storage in the hot water tank where this water is heated during hours when the demand is below the average. In single homes, hot water use averages 20 gal per day pier person. Table 12 gives sug gested storage tank sizes for homes and apartments based on the number of families or baths. HOT WATER HEATERS Various types of heaters are available for supplying the hot water for domestic service in buildings. In any hot water supply system the water should be heated to a temperature between 150 and 180 F. Where the hot water requirements include supplies for kitchens, laundries or process work, the higher temperatures are used. In buildings where steam is available throughout the year, the hot water supply is usually taken from this source. In smaller domestic installations the fuel-burning device is generally automatically arranged so that hot water is supplied the entire year and not merely when the boiler is used for heating purposes. 757 ' HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 Water is heated by various methods using heat exchangers arranged so that the boiler heating medium gives up its heat to the water in the hot water circulating system. These heat exchangers may be classified as follows: 1. Submerged steam heating coil in storage tank. 2. Submerged water heating coil in storage tank. (Fig. 8). 3. Indirect water heater, mounted on side of boiler below water line. (Fig. 9). 4. Submerged indirect water heater, placed in boiler below water line. (Fig. 10). The efficiency of these heaters may be estimated as nearly 100 per cent as the heat loss from surface radiation of the heater and tank shell when covered with insulating material is generally reduced to a minimum. The capacities of these heaters are usually available from manufacturers CHAPTER 44. WATER SUPPLY PIPING AND WATER HEATINC selecting an indirect heater of the proper size to provide for loss of efficiency due to the accumulation of scaling on the coils and piping. Heat exchangers classified according to (3) and (4) may be used with or without a storage tank, but when tanks are omitted, the indirect water heaters should be increased in size so as to heat the water instantaneously as it is needed. The storage tank should be installed as high as possible. Horizontal tanks are preferable for all medium size installations and absolutely essential on larger installations. Where possible the storage tank should be installed with the bottom of the tank at or above the boiler water line. Horizontal storage tanks smaller than 18 or 20 in. diameter are not recommended because of the difficulty of preventing the hot and cold water from mixing, and especially is this an important consideration when large quantities of water are withdrawn. ) hot water to fixtures Fig. 8. Hot Water Heating Coil Submerged in Storage Tank rating tables. The area of the inside surface of a heating coil may be determined from the following equation: . __ Q X 8.33 (Ip -- tj) " . .j. ~ Xo X Im where A -- surface area of coil, square feet. Q = quantity of water heated, gallons per hour. . to = hot water outlet temperature, degrees Fahrenheit. ti = cold water inlet temperature, degrees Fahrenheit. fC0 = coefficient of heat transmission, Btu per hour per square foot surface. For copper or brass coils Ka -- 240 (steam) and 100 (hot water). For iron coils Ka = 160 (steam) and 67 (hot water). tm = logarithmic mean of the difference between the temperature of the heating medium and the average water temperature. tm is approximately = [* - : : Equation 1 may also be used for determining revised heating coil ratings under different temperature conditions as stated in the manu facturers ratings. When selecting a water heater, the conditions of operation should be carefully considered, as well as the location of the storage tank and the piping arrangement between the boiler, heater and tank. It is generally good practice to allow , a margin of safety when 758 Fig. 9. Indirect Water Heater Mounted on Side of Boiler Fig. 10. Indirect Water Heater Placed in Boiler Pipe sizes between the water heater and boiler should be full size of the heater tappings (Table 12). When a heater is connected to a horizontal sectional boiler, it is' recommended that connections be made to all sections and joined together a few inches below the water line as shown in Fig. 8, so that steaming is prevented in those sections which are not connected to the header. " When a steam coil is used for heating the water, an automatic ther mostatic valve may be installed in the steam supply to the coil. The operation of this automatic valve is controlled by a thermostat located in the storage tank which permits the proper amount of steam to enter the coil so as to maintain an even water temperature. An indirect water heater may be used on either a steam or hot water system, and generally this type of heater is provided with a temperature control device located in the boiler water circulating connection to the water heater. The setting on this thermostatic valve may be as low as 140 F or as high as 180 F and may be readily adjusted to meet particular requirements. With this type of control it is impossible to overheat the hot water supply which is an important safety consideration in some installations. This type of system may also be conveniently used during 759 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 the non-heating season with the operation of the fuel burning device controlled by the water heater thermostat. (See Chapter 38.) During the heating season the water heater temperature control functions as a low limit control. When an indirect water heater is applied to a gravity hot water system, it is necessary to provide a valve in the supply to the heating system to prevent the flow of hot water from the boiler when heat is not required in the house. This valve may be controlled from a room thermostat and the automatic fuel-burning device controlled from the water heater thermostat. To prevent circulation in a forced hot water heating system flow control valves may be installed in the flow and return lines which act merely as check valves when the circulating pump is not operating. In this arrangement the pump is controlled by the room thermostat and the automatic fuel-burning device is controlled from the water heater thermostat. STORAGE CAPACITY AND BOILER ALLOWANCES The amount of storage provided in the hot water tank or heater is somewhat a matter of choice but is usually made ample to carry over the peak shortage which is likely to occur and is based on the assumption that only 75 per cent of the storage capacity will be available, as it has been found that if more than this amount is withdrawn from storage, the tank is so cooled down as to make the balance useless. The general rule may be cited that the less the heating capacity the greater must be the storage, and the greater the storage the less may be the heating capacity down to a point where the heating capacity will fail to be sufficient to heat up the tank storage during the periods of small load. Example 5. A heater to supply 500 persons will have an average daily use of about 500 X 40 gal = 20,000 gal and this is an average of ^ = 833 gph but the peak hour will require Mo of 20,000 = 2000 gal and the shortage during the peak hour, if the heating capacity is made to suit the average hourly use of 833 gal, will be 2000 -- 833 = 1167 gal so that the storage capacity, based on 75 per cent being available from this capacity without cooling the tank excessively, will be = 1556 gal. . U.75 , Should it be desired to reduce the size of storage tanks and to use a greater heating capacity, it is only necessary to increase the heating capacity to say 1200 gph which then gives 2000 -- 1200 = 800 gal as the shortage during the peak hour, and the necessary storage will be --= 1067 gal ; or the heating capacity can be increased to 1500 gal, leaving a shortage of 2000 -- 1500 = 500 gal.. Good design requires that the heating capacity be made as small as possible without introducing undesirable amounts of storage, as the heating capacity directly determines the load on the source of heat. As indicated in Example 5, the heating load is proportional to the heating capacity and the boiler capacity must be increased for higher heating capacities and may be reduced for smaller heating capacities with greater storage. It may be assumed that a boiler capacity of about 4 sq ft of equivalent steam heating surface8- (radiation) must be provided for every gallon of water heated 100 F or from 50 F to 150 F, which is Actual requirement for 100 deg temperature difference = -1--0-0-- 2XA0~8~--33 ~ 3.48 sq ft per gallon of water heated. 760 "chapter 44. WATER SUPPLY PIPING AND WATER HEATING Ttps or BOUiDlNO Maximum Probable 13sage GPH Latatohies Private Public D-.w Showebs Slop Sinks Kitchen Pantht Sinks Foot Batbs Wash Tbats Avc. Mat. Use* 20 20 40 300 30 30 20 20 50 turn Ordinary Use Apt. housS Club Gymnasium Hospital Hotel Industrial Laundries Office building Baths Residences Schools y; m. c. a. 50 25 60 100 25 80 100 100 25 80 100 25 100 80 . 100 50 50 100 50 100 100 60 80 oi fixtures likely to be demanding maximum probable usage at any one time. Percentage 35 60 80 45 70 90 100 20 100 50 25 75 Table 14. Hot Water Consumption in Various Types of Buildings for Different Purposes Tttb op Bdodino Conditions Gauoks Hotels Public Buildings Industrial Buildings Restaurants Room with basin only Room with bath (Transient) (Men) (Mixed) (Women) Two-room suite and bath Three-room suite and bath 10 (per day) 40 (per day) 40 (per day) 60 (per day) 80 (per day) 80 (per day) 100 (per day) Public bath or lavatory Public shower Public lavatory with attendant 150 (per day per fixture) 200 (per day per fixture) 200 (per day per fixture) Per office employee Per factory employee Cleaning floors $0.50 Meals $1.00 Meals $1.50 Meals 2 (per day) 5 (per day) 3 (per 1000 sq ft per day) 0.5 (per customer with hand washing) 1.0 (per customer with machine washing) 1.0 (per customer with hand washing) 2.0 (per customer with machine washing) 1.5 (per customer with hand washing) 4.0 (per customer with machine washing) 761 HEAT1NC VENTILATING AIR CONDITIONING CUIDE 1940 the temperature rise most commonly assumed and required. On this basis it will be seen that the various conditions cited in Example 5 will require additional boiler capacity as follows: Heating Capacity (Gph) 833 1200 1500 Additional Boiler Capacity (Sq Ft EDR) 3332 4800 6000 From this it is apparent that it is less costly to provide ample storage and to reduce boiler capacity than to diminish the storage and. supply a greatly increased boiler capacity to compensate. The boiler allowance value of 4 sq ft of equivalent steam radiation for each gallon of water heated through a temperature range of 100 F is based on an hourly heating rate. When reduced heating capacities are desired for economic reasons of boiler design and selection, engineers frequently recommend that the heating rate be extended over a period of two hours in which case the boiler allowance value would be reduced to 2 sq ft of equivalent steam radiation. Similarly, any other heating rate may be established and a corresponding value of boiler allowance deter mined. Reliable information based upon the installations of several heaters in existing heating systems indicates varying arbitrary values of boiler allowances to be used. When these values are selected for usage, a careful analysis of the varying factors involved in determining these values should be considered so that the proper heating allowances may be provided. ESTIMATING HOT WATER DEMAND BY FIXTURES In buildings where the occupancy is doubtful and only the number of plumbing fixtures can serve as a basis for determining the probable hot water demand, the problem is not so simple owing to the fact that a fixture gives no information as to how heavy a service may be demanded from the fixture and this amount of service is really-the governing factor in making an estimate of the probable hot water demand. Table 13 may prove of some value in this respect as it gives the maximum assumed quantity of hot water per hour which will be demanded of any fixture and then gives a percentage of this amount which may be assumed as probable in different types of buildings. Table 14 gives approximate hot water re quirements in various types of buildings. ' Example 6. Let it be assumed that an apartment house with 20 apartments has 20 baths, 20 lavatories, 20 kitchen sinks and 20 laundry trays; what is the probable maxi mum hourly demand for hot water? 20 Baths at 40 gal and 33 per cent.---- 270 gal 20 Lavs, at 20 gal and 25 per cent----------- --------------- ----------------------------------------- ---------------100 gal 20 Sinks at 30 gal and 33 per cent-------- ----- --------------------------------------------------------------------- 200 gal 20 Tray# at 50 gal and 60 per cent:-------------------------------------- --------------------------------------------- 600 gal Total_________--__________________ .1170 gal Probable peak use at one time_________________________________________________ __________ 35 per cent Probable actual peak demand. 409 gpb If three persons are assumed to an apartment the total daily use of hot water should approximate 20 X 3 X 40 gal 2400 gal and if the peak hour is 10 per cent of this amount, the peak hour by this method shows a probable demand of one-tenth of 2400 gal, which indicates that the values in Table 13 are safer 762 Chapter 45 TEST METHODS AND INSTRUMENTS Temperature Measurement, Pressure Measurement, Measuremerit of Air Movement, Air Change Measurements, Meas urement of Relative Humidity, Dust Determination, Heat . Transfer Through Building Materials, Measurement of Heat Exchange for Comfort Conditions, Combustion Analysis, Smoke Density Measurements, Carbon Monoxide Measure- ` ments IN previous chapters, data from many tests and from much research on various divisions of heating, ventilating and air conditioning have been given. On pages 790 and 791 the test codes adopted by the Society for testing and rating of various types of apparatus are listed. This chapter presents a description of many test instruments, and discusses their use. TEMPERATURE MEASUREMENT Changes in the intensity of heat may be determined by several methods such as measuring the change in volume of a liquid, the change in internal pressure of a confined gas, the current set-up between dissimilar metals joined in a circuit, or the change in resistance of an electrical circuit. Thermometers . . The most common method used is the change in volume of a liquid such as mercury or alcohol enclosed in glass. Mercurial thermometers may be used for measuring temperatures from -- 40 F to approximately 1000 F. The lower limit is set by the freezing point of mercury. Since the boiling point of mercury is only about 675 F, the space above the mercury in thermometers designed for higher temperatures must be filled with an inert gas under pressure. Alcohol thermometers may be used for temperatures from --94 F to +248 F. . The more accurate thermometers are individually calibrated and have divisions etched on the stem. The two most common reference points are the freezing and boiling points of water. On the Fahrenheit scale, which is most commonly used in engineering work, there are 180 divisions between these points. On the Centigrade scale which is used by chemists and physicists, there are 100 divisions in this range. The temperature in degrees Fahrenheit equals 9/6 of the temperature in degrees Centi grade, plus 32. For permanent installations, glass thermometers are often protected by metal jackets and equipped with metal scales. Due to the heat 763 HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 capacity and heat conductance of the jacket, it is more difficult to obtain the true temperature at a point with these than with the exposed etched stem type. The latter is usually preferred for test purposes. Where used to measure temperatures in ad net, it may be inserted through a cork or rubber plug. Care must be taken to locate the bulb at the point where the temperature is desired and in many cases several must be used to get a correct average. Most mercury thermometers are calibrated for complete stem immer sion. When incompletely immersed, a stem correction should be made for the most accurate determination. At ordinary atmospheric tem peratures the correction is negligibly small, but it usually is important when measuring high temperatures such as those of steam and flue gas. The emergent stem correction may be calculated by the following equation: K = 0.00009 D (h -- tx) (l) where K = correction to be added, degrees Fahrenheit. D = number of degrees on the thermometer scale which are not immersed. <i = temperature indicated on the thermometer, degrees Fahrenheit. tt = temperature of the non-immersed mercury column, degrees Fahrenheit. 0.00009 = difference in the coefficient of expansion of the mercury and glass. . In some cases, thermometers are calibrated for a certain depth of immersion indicated by an etched mark on the stem. Should such a thermometer be used for full immersion, a negative stem correction would be in order. In selecting a set of thermometers for a test, it is well to compare the group by immersion in a common bath and note variations. The more accurate ones can thus be selected for the more important positions. The interchanging of thermometers at inlet and outlet tends to cancel variations and therefore may result in greater accuracy. In extreme cases of small temperature differences involving large quantities , of heat, it may be advisable to use thermometers graduated in tenths of degrees and mount magnifying glasses, on them for accurate reading. Since the bulb has considerable area, radiant energy may affect tem perature readings'. In measuring room temperatures, care must be taken to locate thermometers away from hot surfaces such as radiators or cold surfaces such as walls or windows. Where this is impractical, shields should be used to screen the bulb from the radiant energy. Thermocouple When two dissimilar metals are joined at two points and a temperature difference exists between these junctions, an electromotive force will be developed. Its magnitude depends upon the metals used and the tem perature difference of the two junctions. Often the cold junction is kept at 32 F by immersion in an ice bath. In other instances, a higher tem perature such as that of the atmosphere is used for this junction. By proper selection of metals, any temperature up to 2900 F may be meas- `Errors in the Measurement of the Temperature (A.S.H.V.E. Transactions, Vol. 35, 1929, p. 473). of Flue Gases, by P. Nicholls and W. E. Rice 764 CHAPTER 45. TEST METHODS AND INSTRUMENTS ured. Readings are obtained by means of a potentiometer or sensitive galvanometer which may be calibrated directly in degrees. A potentio meter balances the electromotive, force against a known electromotive force with no current flowing, hence this method is independent of length and variations in resistance of leads. Calibration of thermocouples for high temperatures may be made against known melting points of metals. Radiation effects may be minimized by using the smallest size of wires consistent with mechanical strength. The use of small wires also makes the thermocouple sensitive to minute fluctuations in temperature. Other advantages of thermocouples are: they are readable at remote points, they may easily and accurately be made recording, and an average temperature may be obtained readily by connecting many couples together in series. Resistance thermometers depend for their operation upon the change of resistance of wire with change in temperature. Their use largely parallels that of thermocouples. Various metals may be used and the range is about the same as for thermocouples. For measuring high temperatures, such as in furnaces, pyrometers are often used. Radiation pyrometers concentrate the radiant energy on a thermopile, and the reading is obtained on a galvanometer or potentio meter. Optical pyrometers match a narrow spectral band, usually red, emitted by the object with that from a standard electric lamp supplied with electric current. PRESSURE MEASUREMENT Barometer The most accurate barometer for determining the atmospheric pressure is the mercurial type, consisting of a tube over 30 in. long closed at the top and standing in a mercury well. The barometric pressure is expressed as the height of the mercury column above the level of the mercury in the well. Such barometers are equipped with an adjustment to compensate for change in level of mercury in the well. The reading at the tube meniscus is obtained on a vernier scale. When extreme accuracy is required, as in determining the thermodynamic properties of vapors at very low absolute pressures, corrections for the variation of density of the mercury column with temperature should be made. Standard density of mercury is taken at 32 F and the conversion factor from inches of mercury to pounds per square inch is 0.491. The following equation may be used to make corrections for tempera ture variations from 32 F for mercury columns: h = h, [1 - 0.000101 (1, - 32)] (2) where h = corrected column at 32 F, inches mercury. hi = measured height of the column, inches mercury. ti = observed temperature of the column, degrees Fahrenheit. Standard atmospheric pressure at sea level is 29.921 in. mercury. Since normal atmospheric pressure decreases about 0.01 in. mercury for each 10 ft increase in elevation, it is important to make a correction if the 765 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CHAPTER 45. TEST METHODS AND INSTRUMENTS elevation of the barometer is not that of the test apparatus. In many cases the barometric reading may be obtained from a nearby weather bureau station. Inquiry should be made as to whether the value is as observed or corrected to sea level. Atmospheric pressure may also be measured by an aneroid barometer which is easily portable. In this type, variations in atmospheric pressure bend the thin surface of a box or tube which contains a reduced pressure. The aneroid type is not as accurate as the mercurial and needs frequent calibration against one of the latter type. Most of the pressure gages used in engineering work indicate the difference between the pressure being measured and the atmospheric pressure. Pressures as measured are called gage pressures: Absolute pressure may be obtained by adding barometer pressure and gage pres sure algebraically. Pressure Cages The Bourdon type gage is a widely used device for measuring pressures. The Bourdon tube is eliptical in cross section and circular in form, and is connected by suitable linkage to a hand which moves over a dial. An increase in pressure tends to straighten the tube and a decrease has the opposite effect. When used with high temperature steam, the tube must be protected by a water seal. When used with ammonia it must be made of steel or other material not attacked by this substance. When used for sub-atmospheric pressure, the gage is known as a vacuum gage, and is usually graduated in inches of mercury. For pressures above atmospheric, it is termed a pressure gage and is graduated in pounds per square inch. Some are made to read in both directions and are termed compound gages. Calibration is usually made with a dead weight tester, consisting of a platform and weights resting on a piston floating on oil. From the area of the piston and the total weight resting on the oil, the pressure at all points in the fluid is determined. Adjustments are pro vided in the gage linkage to make necessary corrections. A correction chart may also be made and used for accurate work. . For comparatively low gage pressures above and below atmospheric, the vertical U tube is a simple and accurate gage and is often used for .test work with various fluids such as mercury, water, kerosene, or alcohol. Readings may be in inches of any of these fluids. I ' gages. The accuracy of a draft gage is very dependent on the slope which * is usually fixed by a built-in spirit level. If one side of a U gage is open to the atmosphere, the gage indicates pressure above or below atmos pheric pressure. If both sides are connected, it indicates the difference in pressure existing between the two points of connection. For measuring extremely low pressures accurately, very sensitive micromanometers of several types are available, such as the Chatelier, the Illinois or Wahlen and the Emswiler23. Calibration of these by a hook gage is impossible, and recourse must be made to fundamental calculations involving gravity of fluids and the principles involved. When proved accurate, a micromanometer is very useful for calibrating draft or slant gages. MEASUREMENT OF AIR MOVEMENT The problem of measuring air movement may be divided into three main parts: when confined in ducts, when circulating in free spaces, and when entering or leaving such space through openings such as grilles. Other gases might be measured by the same methods, but emphasis here will be on air measurements. For determining the velocity, and therefore the volume of air flowing in a duct, such as in the test of a fan or a complete ventilating system, the Pitot tube as described in the A.S.H.V.E. Code* is probably most often used. The tube is a double tube 54 in-, outside diameter with a rounded end up-stream. The inner tube is in. inside diameter at the up-stream end, and the pressure in it is the sum of the velocity pres sure and static pressure at its location in the duct. The outer tube, otherwise sealed, has 8 holes 0.04 in. in diameter and equally spaced around the circumference, and located eight diameters down-stream. A connection to this tube gives the static pressure. If both tubes are con nected to opposite ends of a U gage, the gage indicates velocity pressure. At low velocities the resulting pressure head is so low that it becomes difficult to'get accurate gage readings. The velocities used in many ducts are below the lower limit of determination with gages available. The relation between velocity and velocity pressure may .be used to determine the range of gage required. V = 1096.2 (3) For measuring pressures within a few inches of water of atmospheric pressure, U gages are often made sloping for greater magnification of scale. In commercial gages of this type, commonly termed draft gages, only one tube of small bore is used and the other leg is replaced by a reservoir. Although the scale is calibrated to read in inches of water, a fluid having the density and characteristics of kerosene is often used. It is important, of course, to use a fluid having the same gravity as that for which the gage was originally calibrated, or to use a correction chart with some other fluid. Such gages may be checked one against another to detect errors in gravity of fluid. For more accurate calibration the gage may be checked against a calibrating device working on the U gage principle which uses hook gages and a micrometer screw. It is not con- . sidered desirable to use a slope of less than 1 to 10 in the design of these where V = velocity, feet per minute. /iv = velocity pressure, inches of water. d = density of air, pounds per cubic foot. , Air flow in a round duct is seldom uniform. In general, the velocity is lowest near the edges, and maximum at or near the center. In order Illinois Micromanometer (University of Illinois, Engineering Experiment Station Bulletin No. 120, p. 91). 3The Weathertightness of Rolled Steel Windows, by J. E. Emswiler and W. C. Randall (A.S.H.V.E. Transactions, Vol. 34. 1928, p. 527). 4Standard Test Code for Centrifugal and Axial Fans, Edition of 193k. See also Standard Code for the Testing of Centrifugal and Disc Fans (A.S.H.V.E. Transactions, Vol. 29, 1923, p. 407; Vol. 37, 1931, p. 363). 766 I 767 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 to obtain higher velocities and more uniform flow across the measuring section, it is sometimes possible to reduce the duct to a smaller cross section at the Pitot station by use of a long transition piece. In any case, a large number of readings in two traverses should be taken, with 20 being quite desirable. These should be taken at the centers of equal areas for correct determination of volumes. For round pipe, these would be located from the center by multiplying the radius by the following factors: 0.316, 0.548, 0.707, 0.837 and 0.961. A fundamentally correct method of measurement is obtained with a Pitot tube and therefore it can be used without calibration. Pulsating or disturbed flow will give erroneous results and every effort should be made to remove disturbances in the Pitot tube section. Many forms of Pitot tubes other than the one described have been used and calibrated5. A double-ended tube, one end pointing down-stream, and one up-stream, is sometimes used for low velocities, but it should be carefully calibrated for accurate results. A special form of this tube design consists of two straight J4 in. tubes soldered together, closed at the end, and with a 0.04 in. hole in each tube opposite the line of contact. This tube is useful in exploring velocities on exhaust inlets, such as on hoods placed around grinding wheels. The rounded approach orifice or nozzle of the general type described in the A.S.H.V.E. Unit Heater* and Unit Ventilator7 Codes is a very accurate air measuring device. When it is well made, the coefficient closely approaches unity. The velocity at the mouth is increased over that in the duct, and the resulting increased velocity pressures may be measured more accurately. The discharge from such a nozzle is very uniform and provides a good location for calibration of air velocity instruments8. The Venturi meter is somewhat like the nozzle except for the addition of a down-stream transition section that reduces the friction drop through the measuring apparatus. However, since a good one is expensive to make, the Venturi meter is seldom used with gases, although it is often used to measure liquids. . The thin-plate square-edged orifice has a decided advantage over the rounded approach orifice in cost. Its coefficient is approximately 0.60. The exact value depends on the location of the connections, the pressure drop, the diameter ratio of orifice to pipe, and the sharpness of the edge9. Another method of air measurement uses the thermal electric principle where by means of a measured amount of current, heat is put into the air stream. The temperature rise is measured, and with the specific heat of the air mixture known, the weight of air flowing may be calculated. Heat should be applied uniformly to the mass of air passing, and the small temperature difference must be determined accurately.* 88 'Technical Notes No. 546, (National Advisory Committee for Aeronautics, November. 1935). 'Standard Code for Testing and Rating Steam Unit Heaters (A.S.H.V.E. Transactions. Vol. 36, 1930. p. 165). Standard Code for Testing and Rating Steam Unit Ventilators (A.S.H.V.E. Transactions, Vol. 88, 1932, p. 25). Discharge Coefficients of Square Edged Orifices for Measuring the Flow of Air, by H. S. Bean. E. Buckingham and P. S. Murphy (Bureau of Standards Journal Research, Vol. 2, 1929, p. 561). The Flow of Air Through Circular Orifices in Thin Plates, by J. A. Poison and .1. G. Lowther (University of Illinois, Engineering Experiment Station Bulletin No. 240). 768 CHAPTER 45. TEST METHODS AND INSTRUMENTS Air Currents in Free Spaces One of the instruments useful in determining the velocity of air cur rents in free spaces is the Kata-thermometer. It is essentially an alcohol thermometer with a latge bulb. The stem has two marks, one corre sponding to 95 F, and the other 100 F. The instrument is heated above 100 F, and the time in seconds required for it to cool from 100 to 93 when placed in the air current gives a measure of the non-directional velocity. The usual way of heating the bulb is in a water bath, and it is important to wipe the Kata-thermometer dry before taking the reading. A thermo statically controlled water bath is very convenient to use along with two instruments so one may be heating while the other is in use. For high atmospheric temperatures the high temperature Kata with a range of 130 to 135 F may be used. Usually several readings are taken in a given location and the average used. Each Kata has its own factor etched on the stem, and this factor must be used with the cooling formula or chart for obtaining the velocity. The Kata-thermometer is useful in exploring ventilated spaces to determine whether the proper air movement and distribution is being maintained. The Kata-thermometer also finds use in determining the cooling power of the atmosphere, since it loses heat by radiation and convection when dry, and by radiation, convection, and evaporation when the bulb is equipped with a wetted cloth covering19. Another instrument for measuring low velocity air currents is the heated thermometer anemometer11. This consists of an ordinary mer curial glass thermometer with a resistance winding on the bulb. Current is supplied from an external source in a measured amount. The tem perature rise shown on' this heated thermometer over that shown by an ordinary thermometer at the same location, and the current supplied, make it possible to calculate the non-directional velocity of the air stream. Since a smaller bulb is used than that on the Kata-thermometer, it is less affected by radiant heat sources. Another instrument is the hot wire anemometer which is available in several patterns. In general, a measured current is supplied to raise the temperature of a fine bare wire above the temperature of the surrounding air. With the use of a very fine wire, minute fluctuations in velocity may be measured, and the area exposed to radiant exchange with heated or cooled surfaces is at a minimum. This instrument is easily made remote reading or recording. A group.of.them may be connected together to give the average velocity in a space, or the velocity at individual points within a test space, by suitable switching arrangements12,18. Deflecting Vane Anemometer The deflecting vane anemometer consists of a pivoted vane enclosed in a case, and against which air exerts a-pressure as it passes through the instrument from an up-stream to a down-stream opening. The move- "Temperature. Humidity and Air Motion Effects in Ventilation, by O. W. Arraspadrand Margaret Ingels (A.S.H.V.E. Transactions. Vol. 28. 1922. p. 103). nThe Heated Thermometer Anemometer, by C. P. Yaglou (Journal Industrial Hygiene and Toxicology. Vol. 20. October 1938. No. 8). `Development of Testing Apparatus for Thermostats, by D. D, Wile (A.S.H.V.E. Transactions, Vol. 42, 1936. p. 349). ` `Linear Hot Wire Anemometer, Its Application to Technical Physics, by L. V. King (Journal Franklin Institute, 1916). HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 ment of the vane is resisted by a hair spring and a damping magnet. The instrument gives instantaneous readings of directional velocities on an indicating scale. When used in fluctuating velocities, it is necessary to average visually the swings of the needle to obtain average velocities. This instrument is very useful in locating and measuring peak velocities that may be objectionable in air conditioned spaces. Various attach ments are available, such as a double tube arrangement for obtaining velocities in ducts, and a device to measure static pressures. Another attachment will be mentioned later under the measuring of velocities at inlets and outlets. Each instrument and the attachments for it must receive individual calibration. Propeller or Revolving Vane Anemometer The propeller or revolving vane anemometer consists of a light re volving wheel connected through a gear train to a set of recording dials that read the linear feet of air passing in a measured length of time. It is made in various sizes, 3 in., 4 in., and 6 in. being most common. Each instrument requires individual calibration. At low velocities the friction drag of the mechanism is considerable. In order to compensate for this, a gear train that overspeeds is commonly used. For this reason the correction is often additive at the lower range and subtractive at the upper range with the least correction in the middle range of velocities. Most of these are not sensitive enough for use below 200 fpm, therefore, they are not commercially available for the low velocity range met with in air conditioned spaces. Further discussion follows under air measure- ment at inlets and outlets. Measurement of Velocities at Inlets and Outlets of Ducts In the field it is often advisable to make volume measurements at the face of the supply openings. Often it is hard to get into the duct system, or it is difficult to find sections where the flow would be sufficiently uniform. The many types of approaches and grilles used make a high ' degree of accuracy almost impossible. For the best accuracy the instru- . ment and its application should be checked on a similar approach and grille in the laboratory before use in the field. Where extreme accuracy . is not required, such as in balancing a system, various instruments may be used at the face of the grille. Tests have shown that the propeller type anemometer can be used successfully on the heavier type of supply grilles, such as square mesh of the cast, or pressed pattern14.* The core area is divided into equal squares, and the anemometer is held against the face of the grille for the same length of time in each. To get the air volume in cubic feet per minute, the average corrected velocity in feet per minute thus obtained is multi- ' plied by the average of the gross and net free area of the grille in square feet and by a correction coefficient determined as 0.97 at velocities from 150 to 600 fpm and as 1.00 at higher velocities. On exhaust grilles, the anemometer traverse is made as described previously. The air volume may be determined by multiplying the corrected velocity in feet per minute by the gross or core area of the I4A.S.H.V.E. Research Report No. 857, 911 and 966--Measurement of the Flow of Air Through Registers and Grilles, by L. E. Davies (A.S.H.V.E. Transactions, VoK 36. 1930, p. 201, Vol. 37, 1931, ;p. 619. and Vol. 39, 1933, p. 373). 770 CHAPTER 45. TEST METHODS AND INSTRUMENTS grille in square feet and by a coefficient for average conditions of 0.80. This coefficient takes care of the interference of the bars of the grille and the effect on the anemometer of the air entering an exhaust grille through 180 deg16.10 , When a propeller type anemometer is held in a stream of varying velocities, it tends to indicate higher than the true average, that is, the speed of the propeller is nearer to the top velocity in its area than it is to the minimum velocity. This is the main reason for the large difference in ratings of unit ventilators by the anemometer method and by air volume measurements in a duct approach to the inlet16. Any of the other anemometers described can be used within their range at the face of supply grilles when properly applied. In principle it is a case of finding the velocity at many points and using the average thus found with the correct discharge area at that cross section. The deflecting vane anemometer equipped with a jet on the end of a rubber tube has been found especially convenient and accurate on supply grilles17. On modern air conditioning grilles the core area is used without a cor rection coefficient when the jet is held one inch away from the face of the grille. At this distance the constriction due to the thin bars has disappeared since the small air jets have reunited, and the air stream has not yet spread beyond the core dimensions. With deflecting grilles the exploring jet should be turned to the angle giving a maximum reading. This method of using this instrument is only applicable to supply grilles and cannot be used on exhaust grilles because of static pressure differences at the location of the jet and the instrument case. While hardly a quantitative instrument, smoke is very useful in studying air streams and currents. The application of a more accurate instrument is often made more exact by a preliminary exploration with smoke. A mixture of potassium chlorate and powdered sugar in equal portions gives a very satisfactory non-irritating smoke. It is fired by a match, and since considerable heat is evolved, it should be placed in a pan away from inflammable objects. , AIR CHANCE MEASUREMENTS Atmospheric air contains a certain amount of carbon dioxide. Its concentration is increased within enclosures by the carbon dioxide given off by occupants. The air changes through all means: open windows, infiltration, and mechanical ventilation, may be measured by the carbon dioxide concentration18. The Petterson-Palmquist apparatus has been accepted as the standard device for the determination of carbon dioxide in air. The principle used is absorption by caustic potash solution of the carbon dioxide in a known volume of air, and a remeasurement of the volume in a finely graduated capillary tube. Since the concentrations are in the order of 3 to 10 parts in 10,000, extreme care must be used to 15A.S.H.V.E. Research Report No. 1092--The Flow of Air Through Exhaust Grilles, by A. M. Greene. Jr., and M. H. Dean (A.S.H.V.E. Transactions, Vol. 44, 1938, p. 387), 10A.S.H.V.E. Research Report No. 936--Investigation of Air Outlets in Class Room Ventilation, by G. L. Larson, D. W. Nelson and R. W. Kubasta (A.S.H.V.E. Transactions, Vol. 38. 1932, p. 463). . "A.S.H.V.E. Research Report No. 1076--Air Distribution From Side Wall Outlets, by D. W. Nelson and D. J. Stewart (A.S.H.V.E. Transactions, Vol. 44, 1938, p. 77). "A.S.H.V.E. Research Report No. 959--Indices of Air Changes and Air Distribution, by F. C. Houghten and J. L. Blackshaw (A.S.H.V.E. Transactions. Vnl. 3Q to" - ' HEATING VENTILATING AIR CONDITIONING GUIDE 1940 obtain accurate determinations. Since occupants also give off moisture, the increase in humidity may also be used as an index of ventilation within a space. Humidity determinations are much simpler to make, but the accuracy may be affected slightly by absorption of moisture by hygroscopic materials such as fabrics and wood within the space. Meas ured amounts of either carbon dioxide or water vapor may be added for test purposes. However, neither method is used at the present time, and more direct methods of measuring air supply and air distribution are in favor. . MEASUREMENT OF RELATIVE HUMIDITY Wet- and dry-bulb mercurial thermometers are usually used to deter mine relative humidity. The sling psychrometer is a common mounting of the thermometers to permit swinging. The wet-bulb wick and water for wetting it must be clean, and the temperature of the water should preferably be slightly above the wet-bulb temperature. An air stream velocity of 900 fpm is recommended, although velocities from 300 fpm to 1000 fpm have been found satisfactory for passage over the wet-bulb wick. The velocity may be obtained by whirling the thermometer or by aspirating air over the wet-bulb. In ducts, the air flow itself gives the proper evaporating conditions. Several observations should be made until the minimum temperature is reached. Relative humidity may be obtained from tables or psychrometric charts19. Although it is common practice to use the charts which are based on a barometric pressure of 29.92 in. mercury, a correction for barometric pressure is necessary for ' extreme accuracy. This correction is made by multiplying the relative humidity as determined from the chart by the ratio of the observed barometric pressure and the standard barometric pressure. For temperatures below 32 F, the water on the wick is allowed to freeze, during which time the temperature will drop below the true wetbulb. A thin film of ice is more desirable than a thick one, and it is satisfactory to remove the wick and freeze a thin film directly on the bulb. Care must be taken to read the temperatures accurately due to the slight wet-bulb depressions. Tables for ice conditions must be used90. The dew-point apparatus for humidity measurements consists of a polished plated container cooled by the evaporation of a volatile- liquid within. The temperature at which the first slight water vapor forms is the dew-point. If the temperature is below 32 F, the deposit will appear as frost. Another method of determining humidity is by chemical means in which the water vapor is removed by a drying, agent and weighed on a chemical balance. A thermal conductivity method 'is available for temperatures above 212 F or for extremely low humidities2!. DUST DETERMINATION . The measurement of dust is complicated by the many kinds, involved. Some of the collecting methods are impingement on viscous surfaces, ^Psychrometric Tables for Vapor Pressure. Relative,Humidity and Temperatures of the Dew-Point. 4 {U, 5- Department of Agriculture, Weather Bureau, Washington, D. C.). . A Review of Existing Psychrometric Data in Relation to Practical Engineering Problems, by W. H* Carrier and C. O. Mackey (A S.M.E. Transactions, January, 1537, p. 33; DiscU33ion, AJ5.M.E. Trans' actions, August, 1937, p. 528). . - siGas Analysis by Measurement of Thermal Conductivity, by H. A. Daynes (Cambridge Press, 1933) 772 CHAPTER 45. TEST METHODS AND INSTRUMENTS impingement at high velocity under water, collection on porous crucibles through which air passes, and electric precipitation. Determination may be by direct weighing of samples or by microscopic counting. The most commonly used methods are the modified Hill dust counter using micro scopic count, the Smith-Greenburg impinger which collects samples in water and which are counted under a microscope in a Sedgwick cell22, and the Lewis sampling tube with the analytical determination of the increase in weight of a porous crucible. All reports should state the method of sampling and counting. The A.S.H.V.E. Code for Testing and Rating Air Cleaning Devices used in General Ventilation Work specifies the porous crucible method23. HEAT TRANSFER THROUGH BUILDING MATERIALS The A.S.H.V.E. Standard Test Code for Heat Transmission Through Walls specifies the use of the guarded hot plate for tests on homogeneous materials. It further states that the mean temperature shall be at 60 F and the materials dried. - This code describes the construction and use of the guarded hot box for determining over-all heat transmission coefficients of built-up sections. The standard temperature range through the test section is specified as 80 F and the mean temperature of the wall as 40 F. The Nicholls heat meter is very useful for determining the heat flow through walls of buildings24. MEASUREMENT OF HEAT EXCHANGE FOR COMFORT CONDITIONS Several instruments have been devised to measure the effect of various factors as they relate to the comfort of the body. The principle ones are the Kata-thermometer, Dufton's eupatheoscope, Vernon's globe ther mometer, Winslow and Greenburg's thermo-integrator, and Yaglou's heated globe25,26. These instruments are attempts to stimulate and measure the heat exchanges between the human body and its environ ment. In order to stimulate conditions of hard physical labor, the entire surface of the device is covered with a wet cloth. At present special attention is being given the thermo-integrator as a means of measuring radiant effects of environmental conditions. COMBUSTION ANALYSIS The analysis of flue gases to determine completeness and efficiency of combustion is usually made chemically with the Orsat apparatus. This consists of a measuring burette, a leveling bottle, and three pipettes. Carbon dioxide is absorbed in the first pipette by potassium hydroxide, "Public Health Bulletin. No. 144, 1925, (/. S. Public Health Service). 33Testing and Rating of Air Cleaning Devices Used for General Ventilation Work, by S. R. Lewis (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 277). 34A.S.H.V.E. Research Report No. 685--Measuring Heat Transmission in Building Structures and a Heat Transmission Meter, by P. Nicholls (A.S.H.V.E. Transactions, Vol. 30, 1924. p. 65). ^Instruments and Methods for Recording Thermal Factors Affecting Human Comfort, by C. P. Yaglou, A. P. Kratz and C.-E. A. Winslow (Year Book. American Journal Public Health, 36-37). 3flThe Thermo Integrator--A New Instrument for the Observation of Thermal Interchanges, by C.-E. A. Winslow and Leonard Greenburg (A.S.H.V.E. Transactions, Vol. 41, 1935, p. 149). 773 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 oxygen in the second by potassium pyrogaliate, and carbon monoxide in the third by cuprous chloride. A known volume of gas is drawn in, and after each of the three absorptions the reduced volume is again measured in the burette. Pressure and temperature of the gas sample are kept constant while measuring. Several passes are made through each pipette which contains tubes or glass beads to increase the wetted surface. It is essential that each reaction be completed before the next reaction is started. Since the life of the reagents is limited, it is well to keep a record of the number of samples tested. Care is needed in operation to prevent the pulling of reagents out of the pipettes into the capillary tubing and burette. Many recording gas analyzers are available and are usually found in the larger plants. SMOKE DENSITY MEASUREMENTS A common method of determining the relative density of smoke issuing from chimneys is by visual comparison with the Ringelmann Smoke Charts. A sheet of four ruled charts with varying weights of black lines is used. The sheet is 12 by 26 in. over all on which are four charts, each consisting of 294 squares, 14 wide and 21 high. The width of line and spacings is given in Table 1. Table 1. Ringelmann Smoke Chart Spacings Number op Caro i 2 3 4 Thickness of LINES, MM 1.0 2.3 3.7 5.5 Distance in Clear Between Lines, mm 9.0 7.7 6.3 4.5 The charts are placed 50. ft from the observer and in line with the stack to be observed. At this distance the lines disappear, and the charts appear as varying shades of gray. At times a white chart is added as No. 0 to the left of the four charts 1 to 4, and a black chart to the right as No. 5. . Apparatus using the photo-electric cell has been devised for recording smoke densities in large plants. CARBON MONOXIDE MEASUREMENT In garages and vehicular tunnels carbon monoxide is a constant potential danger. In small amounts it causes headaches and inefficiency, and in larger concentrations it causes collapse and death in rather short periods of exposure. A method of analyzing for carbon monoxide con centrations completes the oxidation of the carbon monoxide in a known volume of sample, in the presence of a catalyst. The heat resulting is measured by a thermocouple calibrated in parts per 10,000 of carbon monoxide*7.** **A Carbon Monoxide Recorder, by S. H, Katz, D. A, Reynolds, H. W. Frevert and J. J. Bloomfield (,U. S. Bureau of Mines, Technical Paper No. 355, 1926). 774 Chapter 46 TERMINOLOGY Glossary of Physical and Heating, Ventilating and Air Conditioning Terms Used in the Text, Standard Abbreviations, Conversion Equations, Drafting Symbols, A.S.H. V.E. Codes Absolute Humidity: See Humidity. Absolute Pressure: The sum, at any particular time, of the gage pressure and the atmospheric pressure. Absolute Temperature: The temperature of a substance measured above absolute zero. ' Absolute Zero: The temperature (--459.6 F) at which the molecular motion of a substance theoretically ceases. This is the temperature at which the substance theo retically contains no heat energy. Acceleration: The rate of change of velocity. In the fps system this is expressed in units of one foot per second per second. .. V at Acceleration Due to Gravity: The rate of gain in velocity of a freely falling body, the-value of which varies with latitude and elevation. The international gravity standard has the value of 980.665 cm per second squared or 32.174 ft per second per second, which is the actual value of this acceleration at sea level and about 45 deg latitude. Adiabatic: An adjective pertaining to or designating variations in volume or pressure not accompanied by gain or loss of heat. When a substance undergoes adiabatic ex pansion, since it does not receive heat from without, the work which it does is at the expense of its internal energy, and therefore its temperature falls; similarly, when it is adiabatically compressed its temperature rises. Air Cleaner: A device designed for the purpose of removing air-borne impurities such as dusts, fumes and smokes. (Air cleaners include air washers and air filters.) Air Conditioning: A process by which simultaneously the temperature, moisture content, movement and quality of the air in enclosed spaces intended for human occu pancy may be maintained within required limits. . Air Washer: An enclosure in which air is forced through, a spray of water in order to cleanse, humidify, or dehumidify the air. * ; . . Anemometer: An instrument for measuring the velocity of moving air. Atmospheric Pressure: The pressure exerted by the atmosphere in all directions; as indicated by a barometer. Standard atmospheric pressure is considered to be 14.7 lb per square inch, which is equivalent to 29.92 in. of mercury. Baffle: A plate or wall for deflecting gases or fluids. Blast: This word was formerly used to denote forced air circulation, particularly in connection with central fan systems using steam or hot water as the heating medium. As applied in this sense; the word blast is now obsolete. : Boiler: A closed vessel in which steam is generated or in which water is heated. Boiler Heating Surface: That portion of the surface of the heat-transfer apparatus in contact with the fluid being heated on one side and the gas or refractory being cooled on the other, in which the fluid being heated forms part of the circulating system; this surface shall be measured on the side receiving heat. This includes the boiler, water walls, water screens, and water floor. (A.S.M.E. Power Test Codes, Series 1929.) 775 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Boiler Horsepower: The equivalent evaporation of 34.5 lb of water per hour from and at 212 F. This is equal to a heat output of 970.3 X 34.5 = 33,475 Btu per hour. British Thermal Unit: The mean British Thermal Unit is 7^= of the heat required to loU raise the temperature of 1 lb of water from 32 to 212 F. It is substantially equal to the quantity of heat required to raise 1 lb of water from 63 to 64 F. One Btu = ,, kwhr. By-pass: A pipe or duct, usually controlled by valve or damper, for short-circuiting fluid flow. Calorie: The mean calorie is of the heat required to raise the temperature of 1 1UU gram of water from Zero C to 100 C. It is substantially equal to the quantity of heat required to raise one gram of water from 14.5 C to 15.5 C. Central Fan System: A mechanical indirect system of heating, ventilating, or air conditioning, in which the air is treated or handled by equipment located outside the rooms served, usually at a central location, and is conveyed to and from the rooms by means of a fan and a system of distributing ducts. (See Chapter 21.) Chimney Effect: The tendency in a duct or other vertical air passage for air to rise when heated, owing to its decrease in density. Coefficient of Transmission: The amount of heat (Btu) transmitted from air to air in one hour per square foot of the wall, floor, roof or ceiling for a difference in temperature of 1 F between the air on the inside and that on the outside of the wall, floor, roof or ceiling. Comfort Line: The effective temperature at which the largest percentage of adults feel comfortable. Comfort Zone (A verage): The range of effective temperatures over which the majority (50 per cent or more) of adults feel comfortable. . Comfort Zone (Extreme): The range of effective temperatures over which one or more adults feel comfortable. (See Chapter 3.) Concealed Radiator: A heating device located within, adjacent to, or exterior to the room being heated but so covered or enclosed or concealed that the heat transfer surface of the device, which may be either a radiator or a convector, does not see the room. Such a device transfers its heat to the room largely by convection air currents. Conductance: The amount of heat (Btu) transmitted from surface to surface in one hour through one square foot of a material or construction, whatever its thickness, when the temperature difference is 1 F between the two surfaces. Conduction: The transmission of heat through and by means of matter unaccom panied by any obvious motion of the matter. . Conductivity: The amount of heat (Btu) transmitted in one hour through one square foot of a homogeneous material / in. thick for a difference in temperature of 1 F between the two surfaces of the material. , Conductor (Heat): A material capable of readily conducting heat. The opposite of an insulator or insulation. . Constant Relative Humidity Line: Any line on the psychrometric chart representing a series of conditions which may be evaluated by one percentage of relative humidity; there are also constant dry-bulb lines, wet-bulb lines, effective temperature lines, vapor pressure lines, and lines showing other physical properties of air mixed with water vapor. Convection: The transmission of heat by the circulation of a liquid or a gas such as air. Convection may be natural or forced. .- Convector: A heat transfer surface designed to transfer its heat to surrounding air largely or wholly by convection. Such a surface may or may not be enclosed or concealed. When concealed and enclosed the resulting device is sometimes referred to as a concealed radiator. (See also definition of Radiator.) (See also Chapter 14.) Decibel: A unit commonly used for expressing sound or noise intensities referred to an arbitrary reference level. It is defined by the relation db = 10 logio , where Pi is ' * o the unknown intensity, and P0 is the reference level which is commonly taken as 10-" watts per square centimeter. Degree-Day: A unit, based upon temperature difference and time, used in specifying the nominal heating load in winter. For any one day there exists as many degree-days 776 CHAPTER 46. TERMINOLOGY as there are degrees Fahrenheit difference in temperature between the average outside air temperature, taken over a 24-hour period, and a temperature of 65 F. Dehumidify: To remove water vapor from the atmosphere; to remove water vapor , or moisture from any material. 4 ]TT Density: The weight of a unit volume, expressed in pounds per cubic foot, d = --. Dew-Point Temperature: The temperature corresponding to saturation (100 per cent relative humidity) for a given moisture content. Direct-Indirect Heating Unit: A heating unit located in the room or space to be heated and partially enclosed, the enclosed portion being used to heat air which enters from outside the room. Direct Radiator: Same as Radiator. Direct-Return System (Hot Water): A hot water system in which the water, after it has passed through a heating unit, is returned to the boiler along a direct path so that the total distance traveled by the water is the shortest feasible, and so that there are considerable differences in the lengths of the several circuits composing the system. Down-Feed One-Pipe Riser (Steam): A pipe which carries steam downward to the heating units and into which the condensation from the heating units drain. Down-Feed System (Steam): A steam heating system in which the supply mains are above the level of the heating units which they serve. Draft Head (Side Outlet Enclosure): The height of a gravity convector between the bottom of the heating unit and the bottom of the air outlet opening. (Top Outlet En closure): The height of a gravity convector between the bottom of the heating unit and the top of -the enclosure. Drip: A pipe, or a steam trap and a pipe, considered as a unit, which conducts con densation from the steam side of a piping system to the water or return side of the system. Dry Air: In psychrometric work, dry air is defined as air without water vapor. This state, though not obtained practically, is used as the basis of calculations. Dry-Bulb Temperature: The temperature of the air indicated by any type of ther mometer not affected by the water vapor content or relative humidity of the air. Dry Return: A return pipe in a steam heating system which carries both water of condensation and air. The dry return is above the level of the water line in the boiler in a gravity system. (See Wet Return.) Dust: Solid material in a finely divided state, the particles of which are large and heavy enough to fall with increasing velocity, due to gravity in still air. For instance, particles of fine sand or grit, the average diameter of which is approximately 0.01 centimeter, such as are blown on a windy day, may be called dust. Dynamic Head or Pressure: Same as Total Pressure. Effective Temperature: An arbitrary index which combines into a single value , the effect of temperature, humidity, and movement of air on the degree of warmth or cold felt by the human body. The numerical value is that of the temperature of still, satu rated air which would induce an identical sensation of warmth. Enthalpy: A measure of the amount of heat to be removed at constant pressure from an air-vapor mixture to reduce the temperature of the mixture to a predetermined datum. The enthalpy includes both latent and sensible heat. In Table 6, Chapter 1, separate values for air and water vapor are given with 0 F as the datum for air and 32 F for water vapor. Entropy: A ratio, evaluated for practical purposes by dividing the heat content of a unit weight of a substance by its absolute temperature. Useful in examining changes during a heat cycle. Entropy is constant during a reversible adiabatic change of state. Equivalent Evaporation: The amount of water a boiler would evaporate, in pounds per hour, if it received feed water at 212 F and vaporized it at the same temperature and atmospheric pressure. Estimated Design Load: The sum of the heat emission of the equivalent direct radia tion to be installed plus the allowance for heat loss of the connecting piping plus the heat requirements of any auxiliary apparatus connected with the system. (A.S.H.V.E. Standard Code for Rating Steam Heating Solid Fuel Hand-Fired Boilers--edition of April, 1932.) 777 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Estimated Maximum Load: The load stated in Btu per hour or equivalent direct radiation that has been estimated to be the greatest or maximum load that the boiler will be called upon to carry. (A.S.H.V.E. Standard Code for Rating Steam Heating Solid Fuel Hand-Fired Boilers---edition of April, 1932.) Extended Heating Surface: See Heating Surface. Extended Surface Heating Unit: A heating unit having a relatively large amount of extended surface which may be integral with the core containing the heating medium or assembled over such a core, making good thermal contact by pressure or by being soldered to the core or by both pressure and soldering. An extended surface heating unit is usually placed within an enclosure and therefore functions as a convector. Fan Furnace System: See Warm Air Heating System. Force: The action on a body which tends to change its relative condition as to rest . - WV . or motion, r------. &t Fumes: Partic. les of soli.d matter resulti.ng from such chemi.cal processes as combus tion, explosion, and distillation, ranging from 0.1 to 1.0 micron in size. Furnace: That part of a boiler or warm air heating plant in which combustion-takes place. Also, a fire-pot. Furnace Volume (Total): The total furnace volume for horizontal-return tubular boilers and water-tube boilers is the cubical contents of the furnace between the grate and the first plane of entry into or between tubes. It therefore includes the volume behind the bridge wall as in ordinary horizontal-return tubular boiler settings, unless manifestly ineffective (i.e., no gas flow taking place through it), as in the case of wasteheat boilers with auxiliary coal furnaces, where one part of the furnace is out of action when the other is being used. For Scotch or other internally fired boilers it is the cubical contents of the furnace, flues and combustion chamber, up to the plane of first entry into the tubes. (A.S.M.E. Power Test Codes, Series 1929.) Gage Pressure: Pressure measured from atmospheric pressure as a base. Gage pressure may be indicated by a manometer which has one leg connected to the pressure source and the other exposed to atmospheric pressure. Grate Area: The area of the grate surface, measured in square feet, to be used in estimating the rate of burning fuel. This area is construed to mean the area measured in the plane of the top surface of the grate, except that with special furnaces, such as those having magazine feed, or special shapes, the grate area shall be the mean area of the active part of the fuel bed taken perpendicular to the path of the gases through it. For furnaces having a secondary grate, such as those in double-grate down draft boilers, the effective area shall be taken as the area of the upper grate plus one-eighth of the area of the lower grate, both areas being estimated as defined above. (A.S.H.V.E. Standard, and Short Form Heat Balance Codes for Testing Low-Pressure Steam Heating Solid Fuel Boilers.) Gravity Warm Air Heating System: See Warm Air Heating System.' Heat- A form of energy generated by the transformation of some other form of. energy, as by combustion, chemical action, or friction. According to the molecular, theory, heat consists of the kinetic and potential energy of the molecules of a substance. The addition of heat energy to a body increases the temperature or the kinetic energy of motion of its molecules (sensible heat) or increases their potential energy of position but does not increase the temperature, as when melting or boiling occurs (latent heat.) Heating Medium: A substance such as water,- steam, air, electricity or furnace gas used to convey heat from the boiler, furnace or other source of heat or energy to the heating unit from which the heat is dissipated. ... Heating Surface: The exterior surface of a heating unit. Extended heating surface, (or extended surface): Heating surface having air on both sides and heated by conduction. from the prime surface. Prime Surface: Heating surface having the heating medium on one side and air (or extended surface) on the other. (See also Boiler Heating Surface.) Heat of the Liquid: The sensible heat of a mass of liquid above an arbitrary zero. Hot Water Heating System: A heating system in which water.is used as the medium, by which heat is carried through pipes from, the boiler to the heating units. . Humidify: To add water vapor to the atmosphere; to add water vapor or moisture^ to any material. ! 778 CHAPTER 46. TERMINOLOGY Humidistat: A regulatory device, actuated by changes in humidity, used for the auto matic control of relative humidity. Humidity: The water vapor mixed with dry air in the atmosphere. Absolute humidity refers to the weight of water vapor per unit volume of space occupied, expressed in grains or pounds per cubic foot. Specific humidity refers to the weight of water vapor in pounds carried by one pound of cVy air. Relative humidity is a ratio, usually expressed in per cent, used to indicate the degree of saturation existing in any given space resulting from the water vapor present in that space. Relative humidity is either the ratio of the actual partial pressure of the water vapor in the air to the saturation pressure at the dry-bulb temperature, or the ratio of the actual density of the vapor to the density or saturated vapor at the dry-bulb temperature. The presence of air or other gases in the same space at the same time has nothing to do with the relative humidity of the space. Hygrostat: Same as Humidistat. Inch of Water: A measure of pressure which refers to the difference in the heights of the legs of a water-filled manometer. Insulation (Heat): A material having a relatively high heat-resistance per unit of thickness. Isobaric: An adjective used to indicate a change taking place at constant pressure. Isothermal: An adjective used to indicate a change taking place at constant tem perature. Latent Heat: See Heat. Laws of Thermodynamics: The first. law states that the total energy of an isolated system remains constant and cannot be increased or diminished by any physical process whatever. The second law states that no change in a system of bodies that takes place of itself can increase the available energy of a system. Manometer: An instrument for measuring pressures; essentially a U-tube partially filled with a liquid, usually water, mercury, or a light oil, so the amount of displacement of the liquid indicates the pressure being exerted on the instrument. Mass: The quantity of matter, in pounds, to which the unit of force (one pound) will give an acceleration of one foot per second per second, m = --W . g Mb, Mbh1: Symbols which represent, respectively, 1000 Btu and 1000 Btu per hour. Mechanical Equivalent of Heat: The mechanical energy necessary to produce 1 Btu of heat energy. J = 778 ft-lb. Micron: A unit of length, the thousandth part of one millimeter or the millionth of a meter. Mol: The unit of weight for gases. It is defined as m lb where m denotes the mole cular weight of a gas. For any gas the volume of 1 mol at 32 F and standard atmospheric pressure is 358.65 cu ft and the weight of a cubic foot is 0.002788 m lb. One-Pipe Supply Riser (Steam): A pipe which carries steam upward to a heating unit and which also carries the condensation from the heating unit in a direction opposite to the steam flow. . One-Pipe System (Hot Water): A hot water system in which the water flows through more than one heating unit before it returns to the boiler; consequently, the heating units farthest from the boiler are supplied with cooler water than those near the boiler in the same circuit. One-Pipe System (Steam): A steam heating system consisting of a main circuit in which the steam and condensate flow in the same pipe, usually in opposite directions. Ordinarily to each heating unit there is but one connection which must serve as both the supply and the return, although separate supply and return connections may be used. Overhead System: Any steam or hot water system in which the supply main is above the heating units. With a steam system the return must be below the heating units; with a water system, the return may be above the heating units. Panel Radiator: A heating unit placed on or flush with a flat wall surface and in tended to function essentially as a radiator. Panel Warming: A method of heating involving the installation of the heating units (pipe coils) within the wall, floor or ceiling of the room, so that the heating process takes iThese symbols ware approved by the A.S.H.V.E., June, 1933. 779 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 place mainly by radiation from the wall, floor or ceiling surfaces to the objects in the room. Plenum Chamber: An air compartment maintained under pressure and connected to one or more distributing ducts. Potentiometer: An instrument for measuring or comparing small electromotive forces. Power: The rate of performing work; usually expressed in units of horsepower, Btu per hour, or watts. Prime Surface: See Heating Surface. Psyehrometer: An instrument for ascertaining the humidity or hygroraetric state of the atmosphere. Psychrometric: Pertaining to psychrometry or the state of the atmo sphere as to moisture. Psychrometry: The branch of physics that treats of the measure ment of degree of moisture, especially the moisture mixed with the air. . Pyrometer: An instrument for measuring high temperatures. Radiation: The transmission of heat through space by wave motion. . Radiator: A heating unit exposed to view within the room or space to be heated. A radiator transfers heat by radiation to objects "it can see" and by conduction to the surrounding air which in turn is circulated by natural convection; a so-called radiator is also a convector but the single term radiator has been established by long usage. Recessed Radiator: A heating unit set back into a wall recess but not enclosed. Refrigerant: A substance which produces a refrigerating effect by its absorption of heat while expanding or vaporizing. Relative Humidity: See Humidity; also discussion relative humidity, Chapter 1. Return Mains: The pipes which return the heating medium from the heating units to the source of heat supply. Reversed-Retum System (Hot Water): A hot water heating system in which the water from several heating units is returned along paths arranged so that all circuits composing the system or composing a major sub-division of the system are practically of equal length. Roof Ventilator: A device placed on the roof of a building to facilitate egress of air. Saturated Air: Air in a space containing as much water vapor as it can hold without any condensing out. In saturated air, the partial pressure of the water vapor is equal to the vapor pressure of the water at the existing temperature. Sensible Heat: See Heat. Smoke: Carbon or soot particles less than 0.1 micron in size which result from the incomplete combustion of carbonaceous materials such as coal, oil, tar, and tobacco. Smokeless Arch: An inverted baffle placed in an up-draft furnace toward the rear to aid in mixing the gases of combustion and thereby to reduce theTsmoke produced. Specific Gravity: The ratio of the weight of a body to the weight of an equal volume of water at some standard temperature, usually 39.2 F. Specific Heat: The ratio of thermal capacity of a substance to that of water at 63 F: Since thermal capacity is measured by unit mass raised one degree in temperature, this ratio is numerically equal to the Btu required to raise one pound of the substance through one degree Fahrenheit. Specific Volume: The volume, expressed in cubic feet, of one pound of a substance. = 1 -5- d = V-h W. Split System: A system in which the heating arid ventilating are accomplished by means of radiators or convectors supplemented by mechanical circulation of air (heated or unheated) from a central point. Square Foot of Heating Surface (Equivalent): Equivalent Direct Radiation (EDR). By definition, that amount of heating surface which will give off 240 Btu per hour. The equivalent square feet of heating surface may have no direct relation to the actual surface area. Stack Height: The height of a gravity convector between the bottom of the heating unit and the top of the outlet opening. Standard Air: As defined by A.S.H.V.E. Codes, standard air is air weighing 0.07488 lb per cubic foot, which is air at 68 F dry-bulb and 50 per cent relative humidity with a barometric pressure of 29.92 in. of mercury. (Most engineering tables and formulae involving the weight of air are based on air weighing 0.07492 lb per cubic foot, which is 780 CHAPTER 46. TERMINOLOGY dry air at 70 F dry-bulb with a barometric pressure of 29.921 in. of mercury. The error involved in disregarding the difference between the above two weights is very slight and in most instances may be neglected.) , Static Pressure: The compressive pressure existing in a fluid. It is a measure of the potential energy of the fluid. Steam: Steam is water vapor which exists in the vaporous condition because sufficient heat has been added to the water to supply the latent heat of evaporation and change the liquid into vapor. Steam in contact with the water from which it has been generated may be dry saturated steam or wet saturated steam. The latter contains more or less actual water in the form of mist. If steam is heated, and the pressure maintained the same as when it was vaporized, its temperature will increase and it will become super heated. Steam Heating System: A heating system in which heat is transferred from the boiler or other source of steam to the heating units by means of steam at, above, or below atmospheric pressure. Steam Trap: A device for allowing the passage of condensate and preventing the passage of steam, or for allowing the passage of air as well as condensate. Superheated Steam: See Steam. Supply Mains (Steam): The pipes through which the steam flows from the boiler or source of supply to the run-outs and risers leading to the heating units. Surface Conductance: The amount of heat (Btu) transmitted by radiation, conduc tion, and convection from a surface to the air or liquid surrounding it, or vice versa, in one hour per square foot of the surface for a difference in temperature of 1 deg between the surface and the surrounding air or liquid. Therm: Symbol used in the gas industry representing 100,000 Btu. Thermal Resistance: The reciprocal of conductance. Thermal Resistivity: The reciprocal of conductivity. Thermostat: An instrument which responds to changes in temperature and which directly or indirectly controls the source of heat supply. Ton of Refrigeration: A unit of power equal to the extraction of 12,000 Btu per hour. Ton Day of Refrigeration: The heat removed by a ton of refrigeration operating for one day; 288,000 Btu. Total Heat: See Enthalpy. Total Pressure: In the theory of the flow of fluids; the sum of the static or radial pressure and the velocity pressure at the point of measurement. Tube (or Tubular) Radiator: A cast-iron heating unit used as a radiator and having small vertical tubes. Two-Pipe System (Steam or Water): A heating system in which one pipe is used for the supply of the heating medium to the heating unit and another for the return of the heating medium to the source of heat supply. The essential feature of a two-pipe system is that each heating unit receives a direct supply of the heating medium which medium cannot have served a preceding heating unit. Underfeed Distribution System (Hot Water): A hot water heating system in which the main flow pipe is below the heating unit. Underfeed Stoker: A stoker which feeds the coal underneath the fuel bed. Unit: As applied to heating, ventilating and air conditioning equipment this word means a factory-built and assembled equipment with apparatus for accomplishing some specified function or combination of functions. (See Chapters 22 and 23.) It is loosely applied to a great variety of equipment. Usually the function is included in the name, and hence come terms like Unit Heater, Unit Ventilator, Humidifying Unit, and Air Conditioning Unit. Units are said to be direct or room, when intended for location, or located in, the treated space; indirect or remote, when outside or adjacent to the treated space. They are ceiling units when suspended from above, and floor when supported from below. Other descriptive words includefree delivery when the unit is not intended to be attached to ducts or similar resistance-producing devices, and pressure when for use with such ducts. Complete description requires the use of several of these qualifying words or phrases. (See Chapter 23.) . 781 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Up-Feed System {Steam): A steam heating system in which the supply mains are below the level of the heating units which they serve. Vacuum Heating System: A two-pipe steam heating system equipped with the neces sary accessory apparatus which will permit operating the system below atmospheric pressure when desired. Vapor: Any substance in the gaseous state. Vapor Heating System: A steam heating system which operates under pressures at or near atmospheric and which returns the condensation to the boiler or receiver by gravity. Vapor systems have thermostatic traps or other means of resistance on the return ends of the heating units for preventing steam from entering the return mains; they also have a pressure-equalizing and air-eliminating device at the end of the dry return. Direct Vent Vapor System: A vapor heating system with air valves which do not permit re-entry of air. Vapor Pressure: The equilibrium pressure exerted by a vapor in contact with its liquid. Velocity: The time rate of motion of a body in a fixed direction. In the fps system it is expressed in units of one foot per second. V -- --. Velocity Pressure: The pressure corresponding to the velocity of flow. It is a measure of the kinetic energy of the fluid. Ventilation: The process of supplying or removing air by natural or mechanical means, to or from any space. Such air may or may not have been conditioned. (See Air Conditioning.) Warm Air Heating System: A warm air heating plant consists of a heating unit (fuel-burning furnace) enclosed in a casing, from which the heated air is distributed to the various rooms of the building through ducts. If the motive head producing flow depends on the difference in weight between the heated air leaving the casing and the cooler air entering the bottom of the casing, it is termed a gravity system. A booster fan may, however, be used in conjunction with a gravity-designed system. If a fan is used to produce circulation and the system is designed especially for fan circulation, it is termed a fan furnace system or a central fan furnace system. A fan furnace system may include air washers and filters. Wet-Bulb Temperature: The lowest temperature which a water wetted body will attain when exposed to an air current. This is the temperature of adiabatic saturation. Wet Return: That part of a return main of a steam heating system which is filled with water of condensation. The wet return usually is below the level of the water line in the boiler, although not necessarily so. (See Dry Return.) ABBREVIATIONS2 Absolute.-............................;............--- Acceleration, due to gravity-......... Acceleration, linear................ ........... Air horsepower:-- ..-- -----------Alternating-current (as adjective) Ampere............ ..................................... Ampere-hour...... ................................ Area.......... ..............-.............................. Atmosphere........ ................................. Average...... .......................................... Avoirdupois...... ........... -...................... Barometer--....................................... Boiler pressure.........................-......... Boiling point....................................... Brake horsepower...... ....................... Brake horsepower-hour................... British thermal unit......................... . Calorie.................................................. ____ abs ....------ g ______ a ...air hp ____ a-c ......amp .anip-hr ______ A ___ atm ------avg ___ avdp ......bar. ......... bp ......... bp ...... bhp ..bhp-hr .......Btu .........cal *From compilations of abbreviations approved by the American Standards Association, Z. 10 a. c. f, and i. As a general rule the period is omitted in all abbreviations except where the omission results in the formation of an English word. 782 CHAPTER 46. TERMINOLOGY Centigram... Centimeter.. ~cg Centimet.er-g_ram-second (.sy.st.em.).. .......................................... cgs Change in specific volume during vaporization............................................... ....................... n Cubic...................................................................... ......................................................... ........... ......... cu Cubic foot-- ..cu ft Cubic feet per minute.................................................................... .................... ...........................cfm Cubic feet per second-............................................................. cf Decibel................................................................................. ;............. 77777777777777777777"db Degree1...... ................................................ ........................... ........................................... ....... deg or Degree centigrade................................................................ .............................. .......... ..................... Q Degree Fahrenheit ......................................................................................... ..............7..7..777.7f Degree Kelvin........ ........ .......... ......... ......................................................... ......... :...7....7.7777k Degree Reaumur,.............................................. ...........;........;................................ --7777777777..R Density, Weight per unit volume. Specific weight-.............................. d or p (rho) d = -L V ' Diameter.......... ........ ............................................................................. .............. D or diam Direct-current (as adjective)__________ ___________ _________ ___________________________d-c Distance, linear.___ _________________________________ _____ ______________________ 7777" s Dry saturated vapor, Dry saturated gas at saturation pressure and temperatureT vapor in contact with liquidSubscript - Entropy. (The capital should be used for any weight, and the small letter for unit weight)-..........;.................................................................................... ................................5 or s Feet per minute--.................................................................... ;....... ;___________ __________ fpm Feet per second.......................................................................................................................7 Jps FootFoot-pound...... .............................................................. ............... -ft -ft-lb Foot-pound-second (system)........................................... ............................... ..7.......... "fps Force, total load.......................................................................... ........... .777.7.7.7.777.7.7.7.7."............ F Freezing point- .....................................-.--......fp Gallon.. --gal Gallons per minute--.............................................................................7777777777777 -gpm Gallons per second.................................. ...... ................~ Grain.......................................................... 777777777777777777777777777777^ Gram... ......................................................................................................................... ...................gm* Gram-calorie................................... g-cal Head.. ..H or h Heat content, Total heat, Enthalpy. (The capital should be used for any weight and the small letter for unit weight)H or h Heat content of saturated liquid. Total heat of saturated liquid, EnthSpy of saturated liquid, sometimes called heat of the liquid _ hf Heat content of dry saturated vapor, Total heat of dry saturated vapor. Enthalpy of dry saturated vapor.......................... ....... ..... ..................................... Heat of vaporization at constant pressure............... .................:____________7 X or hf Horsepower___ --._ ... ................ ..............................................77"" ......... _ hp Horsepower-hour. Inch-............ ...... .. __.hp-hr Inch-pound Indicated horsepower--...................................................... ............... 7........7777--.77.7~ ~ ihp Indicated horsepower-hour.____________ ____ _____ ____ ;_____ ______7777.77.77 ihp-hr Internal energy. Intrinsic energy. (The capital should be used for any wdghtand". the small letter for unit weight)....._.....:................... .............../ 5 U or u Kilogram...,____________ __________________ ____ ;........ ...............7.77.7 .......... ' ke Kilowatt____ _______ _______________ (................................................ ................~ kw Kijowatthour............ .......................................................................... .777777777...................... kwhr Length of path of heat flow, thickness..................................................... Load, total........................ ............................................... \t, MechaO nnicaflAeTfTfiIcAliAeMnActyt .. ......*....... --.................................... -...........--------- ----- --......... --6tn *It is recommended that the abbreviation for the temperature scale, F. C, K, be included in expressions tor numerical temperatures but, wherever feasible, the abbreviations for degree be omitted; as 68 F. 4Not A.S.A. abbreviations. -- 783 r' . HEATING VENTILATING AIR CONDITIONING GUIDE 1940 ./ Ounce... ................................ .......................... ..... .......... .............................. .... .............. 02 Power, Horsepower, Work per unit time.______________ __________ Pressure, Absolute pressure, Gage pressure, Force per unit area_ Quantity (total) of fluid, water, gas, heat; Quantity by volume; Total quantity of heat transferred.. -Q Quality of steam. Pounds of dry steam per pound of mixture.. ~x Revolutions per minute.......................................................... __________________________ ____rpm Saturated liquid at saturation pressure and temperature, Liquid in contact with vapor:Subscript f Specific gravity----------- --------------------------- ------------------------------------------------------------------- sp gr * Specific heat...sp ht or c Specific heat at constant pressurecp Specific heat at constant volume.. Specific volume, Volume per unit weight, Volume per unit mass.. Square foot_______________________________________________ ________ _______ :____ sq ft Sq,uare inch.. ____________sq in. Temperature (ordinary) F or C. ( Theta is used preferably only when l is used for Time in the same discussion)t or 0 (theta) Temperature (absolute) F abs or K. (Capital theta is used preferably only when small theta is used for ordinary temperature)T or 0 (capital theta) Thermal conductance5 (heat transferred per unit time per degree)C ' , r1 R kA q L ti -- ti . Thermal conductance per unit area, Unit conductance (heat transferred per unit time per unit area per degree)Ca r ---- 4 k_ a = A ~ RA = A(.t, -1,) L Thermal conductivity (heat transferred per unit time per unit area, and per degree per unit length).........................................................................................................k . _9_ k = ___d___ - t,) L -- , Surface coefficient of heat transfer, Film coefficient of heat transfer. Individual . ' coefficient of heat transfer (heat transferred per unit time per unit area per degree)--............................................. ............................................................... .................. ./* " 9 .A ' " t, - t, (In general / is not equal to k/L, where L is the actual thickness of the fluid film.) Over-all coefficient of heat transfer, Thermal transmittance per unit area (heat transferred per unit time per unit area per degree over-all) ........................................ V 9 6Terms ending icily designate properties independent of size or shape, sometimes called specific proper ties. Examples: conductivity, resistivity. Terms ending once designate quantities depending not only on the material, but also upon size and shape, sometimes called total quantities. Examples: conductance, transmittance. Terms ending ion designate rate of heat transfer. Examples: conduction, transmission. 784 CHAPTER 46. TERMINOLOGY Thermal transmission (heat transferred per unit time).. ------------ q Thermal resistance (degrees per unit of heat transferred per unit time)_______________ R Thermal resistivity.__________________________________________________________ ________ 1/k Vaporization values at constant pressure, Differences between values for saturated vapor and saturated liquid at the same pressure___________________ _____ Subscript fg Velocity;..................................................................................................................................... V Volume (total)__________________________________________________ V Volume per unit time, Rate at which quantity of material passes through a . machine, Quantity ofheat per unit time, Quantity of heat per unit weightq Watt________________________________________________________ w Watthour._________________________________________________________________________ ___whr Weight of a major item, Total weight.................................. W Weight rate, Weight per unit of power. Weight per unit of time____ _____________ ____v> Work (total)................................................................... W CONVERSION EQUATIONS Heat, Power and Work 1 ton refrigeration Latent heat of ice 1 Btu 1 watthour 1 kilowatthour 1 kilowatt (1000 watts) 1000 mean calorie 1 1 kilogram calorie / 1 horsepower 1 boiler horsepower Weight and Volume ( 12,000 Btu per hour \ 200 Btu per minute 143.5 Btu per pound 778 ft-lb 0.293 whr 252 mean calories 2,655 ft-lb 3.413 Btu 3600 joules 860 mean calories 3.413 Btu 3.517 lb water evaporated from and at 212 F 1.341 hp 56.88 Btu per minute 44,253 ft-lb per minute . 3.969 Btu 3087 ft-lb 1.1627 whr . 0.746 kw 42.42 Btu per minute 33,000 ft-lb per minute 550 ft-lb per second / 33,475 Btu per hour \ 9.808 kw 1 gal (U. S.) 1 British or Imperial gallon 1 cu ft 1 cu ft water at 60 F 1 cu ft water at 212 F 1 gal water at 60 F 1 gal water at 212 F 1 lb (avdp) 1 bushel 1 short ton -{ 231 cu in. 0.1337 cu ft = 27' 7.42 cu in. -{ 7.48 gal 1728 cu in. 62.37 lb 59.83 lb 8.34 lb 7.998 lb / 16 oz \ 7000 grains = 1.244 cu ft = 2000 lb 785 HEATING VENTILATING -'AIR CONDITIONING GUIDE 1940 Pressure 1 lb per square inch 1 oz per square inch 144 lb per square foot 12.0421 in. mercury at 62 F 2.309 ft water at 62 F 27.71 in. water at 62 F / 0.1276 in, mercury at 62 F \ 1.732 in. water at 62 F 1 atmosphere 14.7 lb per square inch 2117 lb per square foot : 33.9 ft water at 62 F 30 in. mercury at 62 F 29.921 in. mercury at 32 F 1 in. water at 62 F I 0.03609 lb per square inch < 0.5774 oz per square inch [ 5.196 lb per square foot 1 ft water at 62 F / 0.433 lb per square inch \ 62.35 lb per square foot 1 in. mercury at 62 F Metric Units 0.49 lb per square inch 1. = 7.84 oz per square inch 1.131 ft water at 62 F 13.58 in. water at 62 F 1 cm = 0.3937 in. 1 in. = 2.540 cm 1 m 3.281 ft I ft 1 sq cm = 0.3048 m = 0.155 sq in. 1 sq in. = 6.452 sq cm 1 sq m , = 10.76 sq ft 1 sq ft . - -- 0.0929 sq m 1 cu cm = 0.06102 cu in. 1 cu in. / = 16.39 cu cm 1 cu m 35.31 cu ft ' 1 cu tt = 0.02831 cu m 1 liter = 1000 cu cm = 0.2642 gal 1 kg = 2.205 lb (avdp) ...... 1 1 lb = 0.4536 kg 1 metric ton = 2205 lb (avdp) 1 gram -- 0.002205 lb (avdp) : 1 kilometer per hour 0.6214 mph 1 gram per square centimeter = f 0.02905 in. mercury at 62 \ 0.3944 in. water at 62 F F 1 kg per sq cm (metric atmosphere) 1 gram per cubic centimeter 1 dyne = 14.22 lb per square inch - . = / 0.03613 lb per cubic inch \ 62.43 lb per cubic foot = 0.00007233 poundals .. V 1 joule 1 metric horsepower 1 kilogram-calorie per kilogram = (10,000,000 ergs \ 0.7376 ft-lb = / \ 75 kg-m per second 0.986 hp (U. S.) = 1.8 Btu per pound . ' 1 gram-calorie per square centimeter = 3.687 Btu per square foot . 1 gram-calorie per square centimeter per centimeter = 1.452 Btu per sq ft per inch . 1 gram-calorie per second per square centimeter 2903 Btu per hour per square {for a temperature gradient of 1 deg C per centi- = meter. 786. foot for a temperature gradient' of 1 deg F per inch of thickness. CHAPTER 46. TERMINOLOGY SYMBOLS FOR HEATING, VENTILATING AND AIR CONDITIONING DRAWINGS6 - . i. The objects of this standard set of symbols are to insure the correct interpretation . of drawings and to conserve drafting room time by establishing simple and unmistakable * .i .symbols for the component parts of the heating and ventilating systems. In preparing . the list of symbols an effort has been made to follow existing practice insofar as possible ' biit the list cannot be expected to match exactly the existing practice of every drafting room. 1. General ________________________ Piping 6. Air Piping ----- ----- *------*------*------- 2. Steam ________________________ Piping 7- Vacuum ----- .----- .------ .------ .------- p>P'ng 3. Condensate___________ ________ __ Piping 8. Gas Piping ----------------------------------- - * c,,Uw,,, ------------------------------------ 5. Hot Water Piping------------------------------------ 10. Oil Piping " 11. Lock and Shield Valve -okh -D*0- 23. Indirect Radiator Plan 12. Reducing Valve 13. Diaphragm Valve 14. Thermostat -ftp- -cJcb J|- 24. Indirect Radiator Elevation 25. Supply Duct, Section 26. Exhaust Duct, Section 15. Radiator Trap' Elevation 16. Radiator Trap Plan 17. Tube Radiator Plan 9 27. Butterfly Damper Plan (or Elevation) 28. Butterfly Damper Elevation (or Plan) 18. Tube Radiator Elevation 19. Wall Radiator Plan P = 20. Wall Radiator Elevation 21. Pipe Coil Plan 0 c=>-- 29. Deflecting Damper Rectangular Pipe 30. Vanes 31. Air Supply Outlet 22. Pipe Coil Elevation 32. Exhaust Inlet am im a 0 0 t From A.S.H.V.E. Code of Minimum Requirements for the Heating and Ventilation of Buildings, edition of 1929, and American Standard Drawings and Drafting Room Practice Graphical Symbols (American Standards Association, Z14.2---1935). 787 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 33. Joint 34. Elbow--90 deg 35. Elbow--45 deg 36. Elbow--Turned Up Flanged Screwed Bell and Spigot Write Salted -e- o-u- --t-- -X- r. r- r c Ott-- 01- GH- Ox- 0-- 37. Elbow--Turned Down Gil- GO O GO G9-- 38. Elbow--Long Radius 39. Side Outlet Elbow--Outlet Down 40. Side Outlet Elbow--Outlet Up 41. Base Elbow jgt r r j r 7L? 42. Double Branch Elbow 43. Single Sweep Tee 44. Double Sweep Tee 45. Reducing Elbow 46. Tee 47. Tee--Outlet Up 48. Tee--Outlet Down .49. Side Outlet Tee--Outlet Up 50. Side Outlet Tee--Outlet Down 51. Cross r T r "1i1n InI f A X-4- -HOD- -o- ^0- -KG*- 40fr -o- -X* Q Q- ' 4^ 4^ 4i- XiiidtiiL llvl/ll X 788 CHAPTER 46. TERMINOLOGY 52. Eccentric Reducer. 53 'Reducer 54. Lateral 55. Gate Valve 50. Globe Valve 57. Angle Globe Valve 58. Angle Gate Valve 59. Check Valve 60. Angle Check Valve 61. Stop Cock 62. Safety Valve 03. Quick Opening Valve 64. Float Operating Valve 65.- Motor Operated Gate Valve 66. Motor Operated Globe Valve 67. Expansion Joint Flanged 68. Reducing Flange 69. Union 70. Sleeve 71. Bushing 789 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 A.S.H.V.E. CODES ; The following codes and standards relating to the design, installation, testing, rating, and maintenance of materials and equipment used for the heating, ventilation and air conditioning of buildings, have been adopted by the American Society of Heating and Ventilating Engineers: , Subject Title Air Cleaning Devices Air Conditioning A.S.H.V.E. Standard Code for Testing and Rating Air Clean ing Devices Used in General Ventilation Worka Code of Minimum Require ments for Comfort Air Con: ditioninga Boilers . (testing) Standard and Short-Form Heat Balance Codes for Testing Low Pressure Steam Heating Solid Fuel Boilers (Codes 1 arid 2)a Boilers (testing) . A.S.H.V.E. Performance Test Code for Steam Heating Solid Fuel Boilers (Code 3)a b Boilers-- Oil Fuel (testing) A.S.H.V.E. Standard Code for Testing Steam Heating Boilers Burning Oil Fuela Boilers A.S.H.V.E. Standard Code for Stoker-Fired Testing Stoker-Fired Steam ` (testing) Heating Boilers3 Boilers (rating) A.S.H.V.E. Standard Code for Rating Steam Heating Solid Fuel Hand-Fired Boilersa Concealed Gravity Type Radiation A.S.H.V.E. Standard Code for Testing and Rating Concealed Gravity Type Radiation (Hot Water Section)a Convectors A.S.H.V.E. Standard Code for Testing and Rating Concealed Gravity Type Radiation (Steam Code) Ethics Code of Ethics for Engineers . Fans Standard Test Code for Cen trifugal and Axial Fans Ween Adopted Reference June. 1933 January, 1938 A.S.H.V.E. Transactions, Vol. 39, 1933, p. 225 A.S.H.V.E. Transactions, Vol. 44, 1938, p. 27 June, 1929 A.S.H.V.E. Transactions, Vol. 35, 1929, p. 322 June, 1929 A.S.H.V.E. Transactions, Vol. 35, 1929, p. 332 June, 1932 a.s.h.v:e. Transactions, Vol. 37, 1931, p. 23 January, 1938 A.S.H.V.E. Transactions, Vol. 44, 1938, p. 366 January, 1929 Revised April, 1930 A.S.H.V.E. Transactions, Vol. 35, 1929, p. 12 Vol. 36, 1930, p. 42 June, 1933 . Revised . January, 1936 A.S.H.V.E. Transactions, ' Vol. 39, 1933, p. 237 Vol. 41, 1935, p. 21, 38 i Vol. 42, 1936, p. 29 January,1931 Revised January, 1936 . A.S.H.V.E. Transactions Vol. 37, 1931, p. 367 Vol. 41, 1935, p. 21, 38 Vol. 42, 1936, p. 29 January, 1922 A.S.H.V.E. Transactions, Vol. 28, 1922, p, 6 (See frontispiece The Guide, 1940) 1938 Edition A.S.H.V.E. Reprintc * "Reprints available. ^Originally adopted by the National Boiler and Radiator Manufacturers Association. - oSee A.S.H.V.E. Transactions. Vol. 29. 1923. p. 407; Vol. 37. 1931. p. 363. 790 CHARTER 46. TERMINOLOGY Subject Garages Title Code for Heating and Ven tilating Garages 1 Heat Standard Test Code for Heat Transmission Transmission through Walls3 Through Walls Minimum Requirements Code of Minimum Require ments for Heating and Ventila tion of Buildings. Edition-1929 Radiators Code for Testing Radiators3 When Adopted June, 1929 Revised January, 1935 January, 1927 Reference A.S.H.V.E. Trans actions, Vol. 35, 1929, p. 355 A.S.H.V.E. Reprint A.S.H.V.E. Transactions, Vol. 34, 1928, p. 253 June, 1925 A.S.H.V.E. Codes January, 1927 A.S.H.V.E. ' Transactions, Vol. 33, 1927. p. 18 Unit Heaters Standard Code for Testing and Rating Steam Unit Heaters3 d Unit Ventilators A.S.H.V.E. Standard Code for Testing and Rating Steam Unit Ventilators3 January, 1930 June, 1932 A.S.H.V.E. Transactions, Vol. 36, 1930, p. 165 A.S.H.V.E. Transactions, Vol. 38, 1932, p. 25 Vacuum Heating Pumps A.S.H.V.E. Standard Code for Testing and Rating Return Line Low Vacuum Heating Pumps3 Ventilation Report of Committee on Ventilation Standards3 June, 1934 August, 1932 A.S.H.V.E. Transactions, Vol. 40, 1934, p. 33 A.S.H.V.E. Transactions, Vol. 38,1932, p. 383 The following Codes and Standards have been endorsed or approved by the American Society of Heating and Ventilating Engineers: Subject Title Sponsored bt Reference . Air Conditioning Equipment Standard Method of Rating and Testing Air Conditioning Equipment American Society of Refrigerating Engineers American Society of Refrigerating Engi neers, New York, N. Y. Chimneys Standard Ordinance for Chim National Board of Chapter 14, ney Construction ' Fire Underwriters The Guide, 1931 Condensing Units Standard Method of Rating and Testing Mechanical Con densing Unitse American Society of Refrigerating Engineers American Society of Refrigerating Engi neers, New York, N. Y. Piping Systems Identification of Piping Systemsf American Society Heating, Piping and of Mechanical .Air Conditioning, Engineers July, 1929 Warm Air Furnaces Standard Code Regulating the Installation of Gravity Warm Air Furnaces in Residences National Warm Air Heating and Air Conditioning Association National Warm Air Heating and A ir Con ditioningA ssociation, Columbus. Ohio ^Adopted jointly by the Industrial Unit Heater Association, and the A.S.H.V.E. Proposed code prepared by Joint Committee of American Society of Refrigerating Engineers, American Society of Heating and Ventilating Engineers. Refrigerating Machinery Association, National Electric Manufacturers Association and Air Conditioning Manufacturers Association. ^Adopted November. 1928, Sponsored by (1) American Society of Mechanical Engineers, (2) National Safety Council. 791 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Table 1. Circumferences and Areas of Circles Diameter IN Inches Area Sqln. Sq Ft y< H H 1 lU IH 2 2H 2H 2H 3 sy* 3H 3H 4 4H *H 5 5K =5%H 6 6Ji 6H 6H 77ma 7 8 m SH w 9 x. 9M 9X 10 10H 11 11H 12 I2M 13 13H 14 14H 15 15M 16 I6H 17 17H 18 18H 19 19M 20 20H 21 21M 22 22H 23 23M 24 24H 25 25H 26 26K 27 27H 0.049 0.196 0.442 0.785 1.227 1.767 2.405 3.142 3.976 4.909 5.939 7.069 8.296 9.021 11.04 12.57 14.19 15.90 17.72 19.64 21.65 23.76 25.97 28.27 30.68 33.18 35.79 38.49 41.28 44.18 47.17 50.27 53.46 56.75 60.13 63.62 67.20 70.88 74.66 78.54 86.59 95.03 103.9 113.1 122.7 132.7 143.1 153.9 165.1 176.7 188.7 201.1 213.8 226.9 240.5 254.5 268.8 283.5 298.6 314.2 330.1 346.4 361.1 380.1 397.6 415.5 433.7 452.4 471.4 490.9 510.7 530.9 SSI.6 572.6 593.9 0.0003 0.0014 0.0031 0.0054 0.0085 0.0123 0.0167 0.0218 0.0276 0.0341 0.0412 0.0491 0.0576 0.0668 0.0767 0.0873 0.0986 0.1104 0.1231 0.1364 0.1504 0.1650 0.1840 0.1964 0.2131 0.2304 0.2486 0.2673 0.2867 0.3068 0.3276 0.3491 0.3713 0 3942 0.4175 0.4418 0.4668 0.4923 0.5185 0.5454 0.6010 0.6600 0.7215 0.7854 0.8520 0.9218 0.9937 1.069 1.146 1.227 1.310 1.396 1.485 1.576 1.670 1.767 1.867 1.969 2.074 2.182 2.293 2.405 2.508 2.640 2.761 2.88S . 3.012 3.142 3.274 3.409 3.547 3.687 3.832 3.976 4.125 CIRCUMFERENCE Inches Feet Diameter IN Inches Area Sqln. Sq Ft Circumference Inches Feet 0.785 1.571 2.356 3.142 3.927 4.712 5.498 6.283 7.069 7.854 8.639 9.425 10.21 10.99 11.78 12.57 13.35 \ 14.14 14.92 15.71 16.49 17.28 18.06 18.85 19.64 20.42 21.21 21.99 22.78 23.56 24.35 25.13 25.92 26.70 27.49 28.27 29.06 29.85 30.63 31.42 32.99 34.56 36.13 37.70 39.27 40.84 42.41 43.98 45.55 47. n 48.69 50.27 51.84 53.41 54.98 S6.55 58.12 59.69 61.26 62.83 64.40 65.97 67.54 69.12 70.69 72.26 73.83 75.40 76.97 78.54 80.11 81.68 83.25 84.82 86.39 0.0652 0.1309 0.1964 0.2618 0.3273 0.3927 0.4582 0.5236 0.5891 0.6546 0.7200 0.7854 0.8510 0.9160 0.9818 1.047 1.113 1.178 1.243 1.309 1.374 1.440 1.505 1.571 1.637 1.702 1.768 . 1.833 1.899 1.964 2.029 2.094 2.160 2.225 2.291 2.356 2.422 2.488 2.553 2.618 2.750 2.880 3.011 3.142 3 273 3.403 3.535 3.665 3.796 3.927 4.058 4.189 4.321 4.451 4.582 4.712 4.845 4.974 5.105 5*236 5.367 5.498 5.629 5.760 5.891 6.021 6.153 6.283 6.415 6.545 6.676 6.807 6.938 7.069 . 7.199 28 28H 29 29K 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 so 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 615.8 4.276 87.97 637.9 4.430 89.54 660.52 4.587 91.11 683.5 4.747 92.63 706.8 4.909 94.25 754.8 5.241 97.39 804.3 5.585 100.5 855.3 5.940 103.7 907.9 6.305 106.8 962.1 6.681 109.9 1018.0 7.069 113.1 1075.0 7.467 116.2 1134.0 7.876 119.4 1195.0 8.296 122.5 1256.0 8.727 125.6 1320.0 9.168 128.8 1385.0 9.621 131.9 1452.0 10.08 135.1 1521.0 10.56 138.2 1590.0 11.04 141.4 1662.0 11.54 144.5 1735.0 12.05 147.7 1810.0 12.51 150.8 1886.0 !3.09 153.9 1963.0 13.64 157.1 2043.0 14.19 160.2 2124.0 14.75 163.4 2206.0 15.32 166.5 2290.0 15.90 169.6 2376.0 16.50 172.8 2463.0 17.10 175.9 2552.0 17.72 179.1 2642.0 18.35 182.2 2734.0 18.99 185.4 2827.0 19.63 188.5 2922.0 20.29 191.6 3019.0 20.97 194.8 3117.0 21.65 197.9 3217.0 22.34 201.1 3318.0 23.04 204.2 3421.0 23.76 207.3 3526.0 24.48 210.5 3632.0 25.22 213.6 3739.0 25.97 216.8 3848.0 26.73 219.9 3959.0 -27.49 223.1 4072.0 28.27 226.2 4185.0 29.07 ` 229.3 4301.0 29.87 232.5 4418.0 30.68 235.6 4536.0 31.50 238.8 4657.0 32.34 241.9 4778.0 33.18 245.0 4902.0 34.04 248.2 5027.0 34.91 251.3 5153.0 35.78 254.5 S281.0 36.67 257.6 5411.0 37.57 260.8 5542.0 38.48 263.9 5675.0 39.41 267.0 5809.0* 40.34 270.2 5945.0 41.28 273.3 6082.0 42.24 276.5 6221.0 43.20 279.6 6362.0 44.18 282.7 6504.0 45.17 285.9 6648.0 46.16 289.0 6793.0 47.17 292.2 6940.0 48.19 295.3 7088.0 49.22 298.4 7238.0 50.27 301.6 -7390.0 51.32 304.7 7543.0 52.38 307.9 7698.0 53.46 311.0 7854.0 54.54 314.2 7.330 7.462 7.592 7.725 7.854 8.116 8.378 8.639 8.901 9.163 9.425 9.686 9.948 10.21 10.47 10.73 10.99 11.26 11.52 11.78 12.04 12.30 12.57 12.83 13.09 13.35 13.61 13.88 14.14 14.40 14.66 14.92 15.18 15.45 15.71 15.97 16.23 16.49 16.76 17.02 17.28 17.54 17.80 18.06 18.33 18.59 18.85 19.11 19.37 19.63 19.90 20.16 20.42 20.68 20.94 21.21 21.47 21.73 21.99 22.25 22.51 22.78 23.04 23.30 23.56 23.82 24.09 24.35 24.61 24.87. 25.13 25.39 . 25.66 25.92 26.18 792 .. .'-i *y CATALOG DATA SECTION %! Heating, Ventilating Air Conditioning 1940 INDEX TO ADVERTISERS . PAGE 795 INDEX TO MODERN EQUIPMENT PAGE 1065 ) In this Catalog Data Section of The Guide 174 manufacturers present a detailed. de scription of the most modern types of heating, ventilating and air conditioning equipment and materials---244 pages of valuable data, : profusely illustrated Alphabetical arrangement of advertisers--on pages 795-800--permits ready reference to the products of a specific manufacturer. For convenience in locating manufacturers' data, the catalog section has been completely - re-arranged. Equipment has been grouped - . in sub-divisions as follows: . Air Conditioning....................... 801-841 Air System Equipment............................ 843-910 Controls and Instruments...................... 911-937 - Heating Systems.............. . ............... .. 939-1012 Insulation................................................ .. . 1013-1051 Various types of apparatus and materials are grouped in their respective classes, and may be located readily by reference--to..these sub-divisions. . ;, . A classified Index to Modern Equipment-- on pages 1065-1088 contains complete listings of manufacturers whose products are described in the Catalog Data Section. - ALPHABETICAL INDEX TO ADVERTISERS Heating Ventilating Air Conditioning Guide, 1940 A Page Acme Heating & Ventilating Co., The, 4224 Lowe Ave., Chicago, 111.................. .......1 821 Aerofin Corporation, 410 S. Geddes St., Syracuse, N. ,Y`.......--............................ -- 862-864 Air Conditioning & Oil Heat (a pub.), 232 Madison Ave., New York, N. Y............ 1054 Air-Maze Corporation, 5202 Harvard Ave., Cleveland, Ohio...--............................. 844-845 Airtemp, Division of Chrysler Corporation, Dayton, Ohio..--..................... .........812-813 Airtherm. Manufacturing Co., 710 S. Spring Ave., St. Louis, Mo.--.......--........ -........ 827 Alco Valve Co., Inc., 2638 Big Bend Blvd., St. Louis, Mo............................................... - 912 Aluminum Aircell Insulation Co., Curtis Bldg., Detroit, Mich--------------------- ^......s........ 1023 American Air Filter Co., Inc., First St. and Central Ave., Louisville, Ky........... 846-847 American Artisan (a pub.), 6 N. Michigan Ave., Chicago, 111------------- --........... -........ 1056 American Blower Corporation, Detroit, Mich.......7....................................................r:.~ 802-803 American Coolair Corporation, Jacksonville, Fla--_........................... ........--............ 878-879 American District Steam Company, North Tonawanda, N. Y-.....................1000,.1014 American Hair & Felt Company, Merchandise Mart, Chicago, 111....................... ......... 1024 American Moistening Company, Providence, R. I........--...................... '.............------------ 857. American Radiator & Standard Sanitary Corporation, Pittsburgh, Pa................. 962-965 American Rolling Mill Co., The, Middletown, Ohio.-.:......... ..........-.................................. 907 American Society of Refrigerating Engineers, 37 West 39th St., New York, N. Y..... 938 American Schaeffer & Budenberg Instrument Div., .. Manning, Maxwell & Moore, Inc., Bridgeport, Conn....... ........................:................ 925 Anderson Products, Inc., Cambridge, Mass............. ................ -.............................................. 1001 Anemostat Corp. of American, 10 East 39th St., New York City, N. Y----------- --------- 895 Armstrong Cork Company, Lancaster, Pa......... ....... :.................................... ......................... 1025 Armstrong Machine Works, 851 Maple St., Three Rivers, Mich........................ 1002--1003 Ashcroft American Gauge Div., Manning, Maxwell & Moore, Inc., Bridgeport, Conn................ ......................... .......................................................... -............... 925 Auer Register Co., The, 3608 Payne Ave., Cleveland, Ohio....... ...............--....---------- 896. Automatic Heat and Air Conditioning (a pub.), 1900 Prairie Ave., Chicago, III.............-............--.......... ..........-..... ...... -............................................... . 1058^1059 Autovent Fan & Blower Co., 1809-23 N. Kostner Ave., Chicago, 111............................ 877: B Babcock & Wilcox Company, The, 85 Liberty St., New York, N. Y...: --...-- 966 E. B. Badger & Sons Co., 75 Pitts St., Boston, Mass--..................................... 1004,1017 Baker Ice Machine Co., Inc., Omaha, Nebr...................... ...... ................ ............ .................. 866 Barber-Colman Company, Rockford, III......................................... -.......................-.......... 897,913 795 HEATING VENTILATINC AIR CONDITIONING CUIDE 1940 B Page Barber Gas Burner Company, The, 3704 Superior Ave., Cleveland, Ohio.................. 992 Barnes & Jones, Incorporated, 129 Brookside Ave., Boston, Mass................................. 940 Barrett Co., The, 40 Rector St., New York, N. Y................................................................. 1026 Bayley Blower Company, 1817 South 66th St., Milwaukee, Wis.................................... 880 Bell & Gossett Company, 3000 Wallace St., Chicago, III.................................................... 941 Bethlehem Steel Company, Bethlehem, Pa....................................................................... ........ 908 . Binks Manufacturing Co., 3114-3140 Carroll Ave., Chicago, III... ........................... 858-859 Bristol Company, The, Waterbury, Conn................................................................................... 916 Brownell Company, The, Dayton, Ohio....... ............................................................................... 985 Brunner Manufacturing Co., Utica, N. Y..... ............................................................................. 867 Buffalo Forge Company, 450 Broadway, Buffalo, N. Y....................................................... 881 Buffalo Pumps, Jnc., 450 Broadway, Buffalo, N. Y............................................................... 996 Burnham Boiler Corporation, Irvington-on-Hudson, N. Y................................................ 967 C Carbondale Division, Worthington Pump & Machinery Corp., Harrison, N. J___ 874-875 Carey, Philip Co., The, Lockland, Cincinnati, Ohio........... ................................................. 1027 Carnegie-IUinois Steel Corporation, Pittsburgh, Pa............ ............................................. . 909 Carrier Corporation, Syracuse, N. Y. .......................................................................................... 804 Celotex Corporation, The, 919 N. Michigan Ave., Chicago, III............................ 1028-1029 Chamberlin Metal Weather Strip Co., Detroit, Mich.......... .................................... 1018-1019 Champion Blower & Forge Co., Lancaster, Pa.......... ............................................................... 882 Chicago Pump Company, 2330 Wolfram St., Chicago, 111______________ _____________ 997 Clarage Fan Company, Kalamazoo, Mich......... ........................................................................ 805 Cochrane Corporation, 3130 N. 17th St., Philadelphia, Pa....................................... ....... 1005 Combustion Engineering Company, Inc., 200 Madison Ave., New York, N. Y..... 988 Coppus Engineering Corporation, 339 Park Ave., Worcester, Mass............ ............... . 848 Crane Co., 836 S. Michigan Ave., Chicago, 111............................... .................................. 968-969 Curtis Refrigerating Machine Co., Division of Curtis Manufacturing Co., 1959 Kienlen Ave., St. Louis, Mo................. .............. .................. -................ I..... ............. 868 Coal-Heat (a pub.), 20 W. Jackson Blvd., Chicago, 111......... ,............................................. 1055 D Davies Air Filter Corp., 390 Fourth Ave., New York,iN. Y........ .................................... 849 DeBothezat Division, American Machine & Metals, Inc., 100 Sixth Ave., New York, N. Y......... .................................. ..................................,................. ................... .. 883 Delco Appliance Division, General Motors,Sales Corp., Rochester, N. Y......... 814-815 Detroit Lubricator Company, Detroit, Mich.._..................... ............................;..... 914-915 Detroit Stoker Company, General Motors Bldg., Detroit, Mich............................. 986-987 Dole Valve Company, 1901-1941 Carroll Ave., Chicago, 111.........._...:...... ;..................... 1006 Domestic Engineering (a pub.), 1900 Prairie Ave., Chicago, 111......................... 1058-1059 C. A. Dunham Company, 450 E. Ohio St., Chicago, 111.......... .................................... 942-943 E. -- Eagle-Picher Lead Company, The, Temple Bar Bldg., Cincinnati, Ohio-..... !........ 1032 Ehret Magnesia Manufacturing Co., Valley Forge, Pa............ ................................ 1030-1031 . 796 , INDEX TO ADVERTISERS Page Farrar & Trefts Incorporated, Buffalo, N. Y........... ........... ................................................. -972 ' ' Fedders Manufacturing Co., 85 Tonawanda St., Buffalo, N. Y........................1.............. 828 Fitzgibbons Boiler Company, Inc., 101 Park Ave., New York, N. Y.................... 970-971 Frick Company (Incorporated), Waynesboro, Pa...... ................ ........................................... 869 julien P. Friez & Sons, Div. of Bendix Aviation Corp., Baltimore, Md...................... 917 Fueloil Journal (a pub.), 420 Madison Ave., New York, N. Y ................................ 1060 Fulton Sylphon Company, The, Knoxville, Tenn............................... :.......................... 918-919 G !i G & O Manufacturing Company, The, 138 Winchester Ave., New Haven, Conn..... 865 Gar Wood Industries, Inc., 7924 Riopelle St., Detroit, Mich.................................... 818--819 General Electric Company, Bloomfield, N. J..................................................................... 816-817 General Electric Company, Schenectady, N. Y...... ........... ...............................-............. 892-893 General Insulating & Mfg. Company, Alexandria, Ind........................................................ 1033 General Refrigeration Corp., Beloit, Wis............ ....................................................................... 870 Grinned Company, Inc., Providence, R. I............'................................................. 944-946,1007 H William S. Haines & Company, 12th and Buttonwood Sts., Philadelphia, Pa-------- 947 Arthur Harris & Co., 210-218 N. Aberdeen St., Chicago, III............................................ 995 Hart & Cooley Manufacturing Co., Holland, Mich..................................... ;........... -- 898-899 Heating Journals, Inc. (a pub.), 232 Madison Ave., New York, N. Y-------------- -------.1054 Heating & Ventilating (a pub.), 140-148 Lafayette St., New York, N. Y---------------- 1061 Heating, Piping and Air Conditioning (a pub.), 6 N. Michigan Ave., Chicago, 111... 1057 Hendrick Manufacturing Co., 48 Dundaff St., Carbondale, Pa.......... ........... -............... 909 Henry Furnace & Foundry Co., 3471 East 49th St., Cleveland, Ohio......................1... 822 Henry Valve Co., 1001-19 Spaulding Ave., Chicago, 111........ .............................................. 920 Hershey Machine & Foundry Co., Motorstoker Div., Manheim, Pa--........................ 989 Hinde & Dauch Paper Co., Sandusky, Ohio:............. .................................................. 1034-1035 Hoffman Specialty Co., Inc., Waterbury, Conn.................................................. c.......... 948--949 I Ilg Electric Ventilating Company, 2880 N. Crawford Ave., Chicago, III.................... 884 Illinois Engineering Company, Chicago, 111.............................................................. 950-951 Illinois Testing Laboratories, Inc., 422 N. LaSalle St., Chicago, 111--....... ................ 921 Independent Register Co., The, 3747 East 93rd St., Cleveland, Ohio.--.......... .......... 901 Ingersoll Steel & Disc Div., Borg-Warner Corp., 310 S. Michigan Ave., Chicago, III. 1022 . Insulation Industries, Inc., 10807 Lynden at Meyers Road, Detroit, Mich.._._____ 1038 Insulite, 1100 Builders Exchange, Minneapolis, Minn............................................... 1036-1037 International Boiler Works Co., East Stroudsburg, Pa............ ........................................... 973 International Exposition Co., Grand Central Palace, New York, N. Y...................... 842 International Fibre Board Limited, Ottawa, Ont., Canada..............................,................ 1039 Iron Fireman Manufacturing Company,. Portland, Oregon'.................................... . 990-991 797 ' . .. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 J Page F. Jaden Manufacturing Co., Inc., Hastings, Nebr........................................................... 829 Jenkins Bros., 80 White St.,'New York, N. Y................................................ .........-............ 1008 Johns-Manville, 22 East 40th St., New York, N. Y........... ,,..................................... 1040-1041 Johnson Service Company, Milwaukee, Wis............... ............... ..... .................................. 922-923 Jones & Laughlin Steel Corporation, Jones & Laughlin Bldg., Pittsburgh, Pa..___ .910 K Kewanee Boiler Corporation, Kewanee, III..... .................................................................. 974-977 Kieley & Mueller, Inc., 40 West 13th St., New York, N. Y.................:................. ......... 1009 Kimberly-Clark Corp., 8 S. Michigan Ave., Chicago, 111........................................ 1042-1043 L Lau Blower Company, The, Home and Orchard Aves., Dayton, Ohio.:...................... 885 Leeds & Northrup Company, 4941 Stenton Ave., Philadelphia, Pa.._.._..................... 924 Libby-Owens-Ford Glass Co., Toledo, Ohio............................................... :......... -J..... 1020-1021 M Manning, Maxwell & Moore, Inc., 11 Elias St., Bridgeport, Conn................................ 925 Marley Co., The, Fairfax & Marley Roads, Kansas City, Mo......._............................... 860 Mario Coil Company, 6135 Manchester Ave., St. Louis, Mo........................................... 871 Martocello, Jos. A. & Company, 229-231 North 13th St., Philadelphia, Pa.-..__ 8611 McCord Radiator and Manufacturing Co., 2587 E. Grand Blvd;, Detroit, Mich... 834 McDonnell & Miller, Wrigley Bldg., Chicago, 111..................... ,,.......... ................... --. 960-961 McQuay Incorporated, 1602 Broadway, N. E., Minneapolis, Minn____ -............. 830-831 . Mercoid Corporation, The, 4201 Belmont Ave., Chicago, 111........................................... 928 Meyer Furnace Company, The, Peoria, 111 ............ ........................................... :.................. 823 Minneapolis-Honeywell Regulator Company, Minneapolis, Minn.......................... 926-927 Modine Manufacturing Co., 17th and Holburn Sts., Racine, Wis.......................... 832-833 Motorstoker Division, Hershey Machine & Foundry Co., Manheim, Pa.................... 989 L. J. Mueller Furnace Co., 2009 W. Oklahoma Ave...Milwaukee, Wis.--............ 824-925 . Mueller Steam Specialty Co., Inc., 40-20 22nd St., Long Island City, N. Y............. 1010 Mundet Cork Corp., 65 S. Eleventh St., Brooklyn, N. Y.,,.............................................. 1044 N Nash Engineering Company, The, South Norwalk, Conn;^____.1............................. 998-999 Herman Nelson Corp., The, Moline, 111................:......................... -......................................... 835 John J. Nesbitt, Inc., Holmesburg, Philadelphia, Pa............................ ............................... 836 Niagara Blower Company, 6 East 45th St., New York, N. Y--..................................... .806 O Oakite Products Inc., 22 Thames St., New York, N. Y........ ........................... ,................ 856 Owens-Coming Fiberglas Corp., Toledo, Ohio.......................... ................--.......... 850-851 . ' 798 ' . . l- f- ' - li..' *''A'1':'1' 'v INDEX TO ADVERTISERS . Page ` Pacific Steel Boiler, Div., U. S. Radiator Corp., Detroit, Mich....................................... 978 s Pacific Lumber Company, The, 100 Bush St., San Francisco, Calif............ ................. 1045 Palmer Company, The, 2506 Norwood Ave., Cincinnati (Norwood), Ohio...... ;........ 929 * Parks-Cramer Company, Fitchburg, Mass......................................................................... 807 Penn Electric Switch Co., Goshen, Ind~...................... ............................................................... 932 Plumbing and.Heating Journal (a pub.), 515 Madison Ave., New York, N. Y------ 1062 Pocahontas Fuel Company, Inc., 1190 E. 152nd St., Cleveland, Ohio......................... 826 H. W. Porter & Co., Newark, N. J............................-................................................................... 1015 Powers Regulator Co., The, 2719 Greenview Ave., Chicago, 111............................... 930-931 R i 5 Refrigeration Economics Co., Inc., Canton, Ohio.__.............................................................. 837 Ric-wiL Company, The, Union Commerce Building, Cleveland, Ohio..... ................... 1016 Ruberoid Co., The, 500 Fifth Ave., New York, N. Y............................................... 1046-1047 S Sarco Company, Inc., 183 Madison Ave., New York, N. Y....................................... 952-953 Servel, Inc., Evansville, Ind........................................................................................................ . 872 Sheet Metal Worker (a pub;), 45 West 45th St., New York, N. Y............... ...... ;........ 1063 Smith Twin Tubular Boiler Co., Inc., State Rd. & Cottman St., Philadelphia, Pa 979 H. J. Somers, Inc., 6063 Wabash Ave., Detroit, Mich................................ ....................... 854 Spence Engineering Co., 28 Grant St., Walden, N. Y..... ........................... ........................ 933 Spencer Heater Division, Aviation Mfg. Corp., Williamsport, Pa................ .......... 980-981 Standard Lime & Stone Company, The, First National Bank Bldg., Baltimore, Md. 1048 Staynew Filter Corporation, 6 Leighton Ave., Rochester, N. Y..................... ......... 852-853 B. F. Sturtevant Co., Hyde Park, Boston, Mass---------i................. 1...................................... 886 T Taylor Instrument Companies, Rochester, N. Y............................ ................................ 934r-935 Todd Combustion Equipment, Inc., 601 W. 26th St., New York, N. Y...................... 994 Torrington Mfg. Co., The, 50 Franklin St., Torrington, Conn--.............................. 887-889 Trane Company, The, 2021 Cameron Ave., LaCrosse, Wis........................................ 838-839 Tuttle & Bailey, New Britain, Conn....--...............i.......;.....................-........................ . 902-903 U Underground Steam Construction Co., 75 Pitts St., Boston, Mass............................... 1017 Unit Heater and Cooler Co., The, Wausau, Wis........................... ................. ....................... 840 United States Air Conditioning Corp., 2101 Kennedy St., N. E., Minneapolis, Minn....... .................................................................. ......................... ............ ....... 810 United States Gauge Co., 44 Beaver St., New York, N. Y...... ..... ................................... 936 * 799 u . , Page United States Gypsum Company, 300 W. Adams St., Chicago, 111.:............................. 1049 United States Radiator Corporation, Detroit, Mich_................................................. .. 982-983 United States Register Co., Battle Creek, Mich........................................................ ........... 904 Universal Cooler Corporation, Detroit, Mich................... ..................................................... ; 873 V Vilter Manufacturing Company, The, Milwaukee, Wis.............................. ........................ 876 Vinco Company, Inc., The, 305 East 45th St., New York, N. Y...,,....................... 958-959 W Wagner Electric Corp., 6400 Plymouth Ave., St. Louis, Mo............................................ 894 Warren Webster & Company, Camden, N. J--,.................................. ......................... 954-957 Waterloo Register Company, The, Waterloo, Iowa.......................................................... . 905 Webster Engineering Co., 419 W. 2nd St., Tulsa, Okla....................................................... 993 Weil-McLain Company, 641 W. Lake St., Chicago, III....... .............................................. 984 Western Felt Works, 4029-4117 Ogden Ave., Chicago, 111................................................. 1050 Westinghouse Electric & Manufacturing Co., Edgewater Park, Cleveland, Ohio.... 855 Westinghouse Electric & Manufacturing Co., 653 Page Blvd., Springfield, Mass. 808-809 White-Rodgers Electric Co., 1293 Cass Ave., St. Louis, Mo____________ __________ _ 937 Wickwire Spencer Steel Co., 500 Fifth Ave.; New York, N. Y........ ............ .................. 906 Williams Oil-O-Matic Heating Corporation, Bloomington, 111.......................................... 820. L. J. Wing Mfg. Co., 59 Seventh Ave., New York, N. Y............ .................... .......... 890-891 Wood Conversion Co., First National Bank Bldg., St. Paul, Minn............. ................. 1051 Worthington Pump & Machinery Corp., Harrison. N. J.............................. ............... 874-875 Wright-Austin Co., 317 W. Woodbridge St., Detroit, Mich........................................... 1011 ' Y Yarnall Waring Co., 7600 Queen St., Philadelphia, Pa____ _____:------------ :...................... 1012 York Ice Machinery Corporation, York, Pa............................................................................. 811 Young Radiator Company, Racine, Wis:........................................ ..................................... 841 800 ' AIR CONDITIONING Equipment for complete air conditioning systems, consisting of an assembly of apparatus for air circulation, air cleaning and heat transfer, with control apparatus for maintaining temperature and humidity within prescribed limits, has many commercial, comfort, and industrial applications. Systems for all year, winter and summer service, and special processing work are presented in four divisions . . . Pages 802-841. , CENTRAL SYSTEMS (p. 802-811) ! Complete assembly of4 supply and return ducts serving one or more spaces, con nected with some or all of the following equipment: fans, motors, heat transfer surfaces, humidifiers, dehumidifiers, refrigeration machinery, air cleaning devices and control equipment. An outline of the design procedure generally used to create a modern central air conditioning system is given in Chapter 21 of the Technical Data Section. DIRECT FIRED UNITS (p. 812-820) Automatic heating and comfort air conditioning apparatus suitable, for residential and small commercial applications designed to give results similar to the larger central systems provide direct fired oil, gas or coal heating units, filtration, fan controls, etc. The Technical Data Section, Chapters 11, 13 and 20 cover this type of equipment. FAN-FURNACE SYSTEMS (p. 821-826) , Winter air conditioning and summer ventilation for residences are provided by Automatic fired fan-furnace systems. As in the larger central systems these in stallations clean, heat and'humidify the air, and if desired, auxiliary units will provide cooling. - In Chapter 20 on Mechanical Warm Air Furnace Systems will be foun6 details of the design of this type of system. UNIT HEATERS, COOLERS (p. 827-841) For complete or partial air conditioning there are a variety of self-contained units. Such units may be complete in themselves, employing their own direct means of air cleaning, heating distribution and source of refrigeration.. The various functional elements of unitary equipment are given in Chapters 22 and 23, for Unit Heaters, Ventilators, Humidifiers, Conditioning and Cooling Units and Attic Fans. Manufacturer's products shown in this division are designed for specific applications. Consult the Index to Modern Equipment for additional products of these manufacturers. 801 Air Conditioning Central Systems American Blower Corporation Division of American Radiator and Standard Sanitary Corporation General Offices and Factory Detroit, Mich. Branches in All Principal Cities AIR CONDITIONING -- HUMIDIFYING -- DEHUMIDIFYING -- COOLING -- VENTILATING -- HEATING -- VAPOR-ABSORPTION -- DRYING -- AIR WASHING AND PURIFICATION -- EXHAUSTING EQUIPMENT AND MECHANICAL DRAFT APPARATUS. American H.S. Fans For heating, ventilating, cooling and air conditioning systems. High volumetric and mechanical efficiency. Available in a complete range of sizes and arrangements. Write for Bulletin No. A-403. American Blower Central Air Conditioning Systems For more than 30 years, particularly adapted to heating, ventilating, air wash ing, purifying and cooling large buildings. Write for complete data. . Ventura Ventilating Fan For exhausting bad air, odors, steam, etc., in a wide range of buildings and in dustrial processes, restaurants, garages, etc. Write for Bulletin No. A-31029. American Blower Dehumidifiers and Washers . Fordehumidifying, cooling and washing air in connection with central systems, for air conditioning, for process work or for use with a ventilating system where large quan tities of fresh, washed air are required. Thousands of these dehumidifiers are al ready in operation in theatres, public buildings, office buildings, garages, hotels and industrial plants. Write for Special Bulletin No. 3623. 802 American Blower Corporation Air Conditioning system. TYPES OF AMERICAN BLOWER CORPORATION AIR HANDLING AND CONDITIONING EQUIPMENT All types of air handling and air conditioning equipment for industrial applications, process work, drying, cooling; also equipment for stores, offices, shops, public buildings, power plants, etc., and attic ventilation for homes. American Blower Series H Conditioner For installation in stores, res taurants, offices and other com mercial establishments. May be installed in present buildings or new buildings for cooling, venti lating, dehumidifying as wejl as heating and humidification. Write for technical Bulletin No. 5627. American Blower Series K Conditioner For use with a duct system in a wide variety of air con ditioning applications. For complete data on this con ditioner write for Bulletin No. 3927. Decaiorator Steam Refrigeration Units Furnished for air condition ing and process cooling. By means of a jet of steam and the flow of condensing water, they function to produce cool, re frigerated water at any tem perature above 35 F. For com plete data on steam refrigera tion, send for Bulletin No. 3727. Ventura Home Conditioner For comfort cooling by means of attic . ventilation. Made in various sizes for all home needs. No refrigerating machine required. Thousands already in operation. Write for Bulletin No. A-31029. 803 Air Conditioning Central Systems Carrier Corporation Home Office and FACTORIES: Syracuse, N. Y. International DIVISION: Syracuse, N. Y. Atlanta Boston Chicago Cincinnati Cleveland Dealers In Principal Cities Marine Division: 405 Lexington Ave. New York City Branch Sales Offices: Dallas Detroit Kansas City Los Angeles New Orleans New York City Philadelphia St. Louis San Francisco Washington AIR CONDITIONING lor FACTORY--BUSINESS--HOME CENTRAL STATION SYSTEM--Fans, Humidifiers, Dehumidifiers, Heaters, Filters, Controls, for large factories, theatres, stores, etc. UNITARY EQUIPMENT--Air conditioning equipment complete in single unit for room, home, business, factory, processing, product cooling, and dehydration. Residential air conditioning and automatic heating units for gas, oil or coal. . SELF-CONTAINED EQUIPMENT--Three to fiffeen-ton units for summer air con ditioning in offices and commercial installations. One-half and three-quarter tqn units for summer air conditioning in individual rooms and offices. Room ventilator for circulation, ventilation, filtering, and pollen removal. REFRIGERATION for AIR CONDITIONING--PROCESS--PRODUCT COOLING--COOLING OF LIQUIDS AS BRINE, OIL, BEVERAGES, AND CHEMICAL SOLUTIONS CENTRIFUGAL REFRIGERATION MACHINES--100-1100 tons CentrifugalRe frigeration for Central Station and multi-unitary air conditioning equipment, pro cessing, and product codling, and condensation of vapors such as ammonia, chlorine, and solvents without the intermediary heat transfer involving use of brine. Reciprocating Condensing Units to 100-tons using Freon, for Central Station and unitary air conditioning equipment, processing and product cooling. EVAPORATIVE CONDENSER--For use with Refrigeration Units. Water cooling for Diesel engines and cooling of liquids used in processing. UNIT HEATING for FACTORY--BUSINESS DISC FAN TYPE of suspended unit for steam, hot water, gas. CENTRIFUGAL FAN TYPE--suspended or floor mounted. There is a Carrier system exactly fitted to each requirement and the nearest Carrier dealer or office of Carrier Corporation offers a complete service in solving any air con ditioning, drying, space heating or refrigerating problem. 804 Air Conditioning Central Systems Clarage Fan Company Kalamazoo, Michigan Sales Engineering Offices (Consult Telephone Directory) CLARAGE AIR HANDLING AND CONDITIONING EQUIPMENT For Over a Quarter-Century Clarage lias been a leading manufacturer of air handling and conditioning equipment. There is a Clarage fan or blower, condi tioning unit or system to meet every need, from the simplest ventilating or cooling job to the most exacting temperature and humidity control installation. Whatever your ventilating, unit heating, cooling, drying, air cleaning, humidifying, dehumklifying or complete air conditioning problem, we can meet your requirements successfully and economically. Clarage Experience coversevery conceivable type of installation, commercial, industrial and public build ing. Clarage equipment is used in the largest industrial plants, office buildings, auditoriums, theatres, hotels, restaurants, retail stores, hospitals,churches and schools. Architects, Engineers and Contractors find our service specially helpful. This Company is an inde pendent manufacturer selling through regular trade channels, and cooperating fully with those who specify and those who install. Your inquiry for data on any Clarage product is invited. Write for Bulletins. Clarage Systems for complete air conditioning in public buildings and industrial plants. Multitherm Units for complete conditioning, summer cooling, or winter heating. Unicoil Units for use in small air conditioning systems. Clarage Fan with Vortex (con stant speed) Volume Control for ventilation and air conditioning. with Syncrotherm Temperature Control for factory heating. 805 Unitherm Unit Coolers for pro duct cooling and refrigeration. il Air Conditioning ", Niagara Blower Company AIR ENGINEERING EQUIPMENT AND SYSTEMS General Sales Office: 6 East 45th Street, New York City . Central Division Sales Office: 37 W. Van Buren St., Chicago. III. Buffalo Rochester Boston Detroit Pittsburgh Seattle Atlanta Cincinnati San Francisco Charlotte, N. C. Oklahoma City Kansas City 18 Years' experience in the engineering, design and installation of complete air conditioning PRODUCTS--Exact Control Air Conditioning, Humidifying, Dehumidifying, Comfort Systems, Niagara Air Conditioners, High Humidity Spray Coolers, Fan Coolers, Fan Heaters, Cooling Coils, Heating Coils, Evapora tive Aero Condensers, Aero Liquid Coolers. NIAGARA AIR CONDITIONING SYSTEMS For human comfort and for all industrial applications requiring controlled climatic conditions of temperature, relative humidity, air purity and air movement. NIAGARA AIR CONDITIONER, TYPE A Available both in floor mounted and space-saving sus pended types. Maintains constantly or makes any change required in temperature and relative humidity. NIAGARA AIR CONDITIONER, TYPE X (Illustrated) A year around air conditioning unit providing winter heating and humidifying and summer cooling and dehu- midifying. NIAGARA FAN COOLER and DISK FAN COOLER For comfort cooling, process cooling, low temperature storage for dairies, fruits, meats, food products, fur storage Niagara Type X Air Condition ing and Cooling Equipment was designed especially to make quali ty engineering and construction available at low installation cost in capacity ranges from Yt ton vaults, etc. NIAGARA SPRAY COOLER For all cooling applications, requiring high humidity or high capacity in small space. Ini-, 2-, 3-, and 4-fan units--seven sizes. Patented. NIAGARA "NO FROST" SYSTEM Using Niagara "No Frost" Liquid in spray coolers, prevents frosting of cooling coils, automatically keeps spray solution at proper concentration, gives freedom from brine troubles, corrosion. Constant efficient operation. Patented. NIAGARA COOLING COILS. 13 standard lengths for blast cooling installations in both 20-in. and 30-in. widths. Manufactured in aluminum and copper. . / NIAGARA EVAPORATIVE AERO CONDENSER ... (Illustrated) Saves power and water cost utilizing atmospheric air to remove heat of condensation. Patented. . NIAGARA "DUAL" COOLERS f Simultaneously cools a room and furnishes chilled water' as a refrigerant. Saves coils and operating troubles in milk plants and elsewhere. Patented. . NIAGARA FAN HEATERS and DISK FAN HEATERS For heating and ventilating large areas. Units of the highest quality in engineering material and workmanship. - NIAGARA AIR SUPPLY HEATER Balances exhausted air in factories when exhaust systems are operating, saves steam and power, gives more effective heating. Patent pending. r NIAGARA ALUMINUM HEATING COILS .. ., _ For use with fan heating systems giving the. advantage FmnShTfJ"Zf-Ziih f aluminum, light weight and resistance to corrosion. t oil refrigerants. Complete range of sizes. 806 . ; Air Conditioning Central Systems Parks-Cramer Company Fitchburg, Mass. Charlotte, N. C. CERTIFIED CLIMATE Complete Air Conditioning Systems including Heating, Cooling, Humidifying or De-humidlfying, Air Changing, Refrigeration, Air Filtering, Air Washing AUTOMATIC REGULATION Merrill Process System of Hot Oil Circulation for Heating Industrial Materials Central Station Psychrostat Pettifogger Central Station Air Conditioning A centrally located AIR WASHER supplying correct amount of moisture with positive pre-determined air change. Usually includes indirect radiation for heating --may include refrigeration for cooling or de-humidifying. Features absolute control and centralized equip ment. Helps in many industries, notably, Textiles (Cotton, Wool, Worsted, Silk, Rayon, Jute); Printing and Lithographing; Cigar, Cigarette and Tobacco; Clothing; Paper and Envelope; Leather and Shoes; Wood Products; Cereals, Storage of Perishables; Cera mics; Celluloid; Glassine Paper; Starch and Dextrine; Cement; Confectionery. Installations similar in design are effective in Hospitals, Art Galleries, Auditoriums, and Restaurants . . . Nozzles for Central Station Air Washers. High Duty Humidifier Water under pressure generates spray. Excess water returns to filter tank and recirculates. Evaporation per unit high; two sizes of heads each with three sizes of nozzles give flexible capacity for varying conditions. Circulation increased by individual motor-driven fan. Spray thoroughly diffused and distributed over wide area. Turbo and Turbomatic Humidifiers (not illustrated) . Efficient humidifiers of the atomizer type. For direct humidification and as humidity boosters for Central Station systems of all makes. Self-cleaning. Parks Automatic Airchanger For use with High Duty or Turbo Humidifiers. Insures fixed humidity and maximum evaporative cooling. Automatic Regulation The Psychrostat for accuracy, durability, sensitivity. Hygrostat (not illustrated) where requirements are not so exacting. Psychrostat employs the principle of the Sling Psychrometer, used by U. S. Government in all Weather Bureau Stations. An Air Conditioning System is no better than its Regulation. The Pettifogger A compact humidifier for offices, stores, storerooms, testing laboratories, and other isolated departments. Entirely self-contained in attractive lacquered copper casing. Permanently though flexibly Connected to water and electrical supplies. Automatic control. Adjustable capacity. Reduce dust. Neutralizes drying effect of heating. Conditions textiles and other hygroscopic substances for testing purposes. 807 Air Conditioning Central Systems Westinghouse Electric & Manufacturing Co. 653 Page Blvd., Springfield, Mass. Sales, engineering and service available through Authorized Engineering Contractors in all principal cities UNIFIED Air Conditioning Equipment for Commercial Building Applications APPLICATION--Westinghouse equip ment provides air conditioning for every building application. Every unit is engi neered by Westinghouse and matched in capacity and performance to operate in a Unified System. Equipment is applied in carefully engineered installations, with re sponsible maintenance service to assure continuing efficiency. COMPRESSORS AND CONDENS ING UNITS--Hermetically-sealed to con serve power and efficiency. Dust, dirt and trouble sealed out. No seal leaks. All operating parts accessible. Light weight and compact. AIR CONDITIONING UNITS--In corporate blower, heat transfer surfaces, humidifiers and filters. Horizontal and vertical types. Sizes to fit all compressors. AQUAMISERS (Evaporative Con densers)--Reduce water consumption 90 per cent to 95 per cent. Sizes to match all compressors in which water consump tion is a factor. Hermetically-Sealed Compressors and Condensing Units Type Capacity Btu xt Hour Dimensions--Inches* Hp Nominal Rating tMaximum Length Width Height fApprox. Net Weight Lb CLD- 45 CLD- 90 CLD- 135 CLS- 205 CLS- 275 CLS- 415 CLS- 550 CLS- 640 CLS- 850 CLS-1320 CLS-1980 CLS-2550 CLS-3400 1 23* 3% 5 7% 10 15 20 25 40 60 75 too 12000 26900 4S000 70000 91000 140000 181000 222000 294000 455000 653000 915000 1212000 15700 41000 60800 94500 126000 186000 225000 302000 393000 615000 896000 1155000 1529000 23% 21 21 41 41 64 64 80% 80% 92% 96 95% 18 20% 20% |9% 19% 19% 19% 19% 19% 26% 26% 34 34 16% 36% 36% 40% 40% 40% 40% 40% 40% 49% 49% 64 70 235 440 460 900 900 1720 1720 2080 2080 _ 3760 3775 7300 8100 ' . tRating at 50 F evaporating temperature. 25 F superheat and 100 lb per square inch condensing pressure. {Dimensions and weights are for complete water-cooled condensing units. (See also Page 855) Westinghouse Electric & Manufacturing Co. Air Conditioning Central Systems [type AF- 16 AF- 27 AF- 37 AH- 27 AV- 27 AH- 55 AV- 55 AH- 83 AV- 83 AH-103 AV-103 AH-124 AV-124 AH-154 AV-154 Air Conditioning Units Nominal Capacity Air Delivery Cfm Dimensions--Inches Length Width Height 480- 1120 810- 1890 IMO- 2590 1500- 2250 1500- 2250 2580- 3870 2580- 3870 4080- 6120 4080- 6120 4930- 7394 4930- 7394 5800- 8700 5800- 8700 7874-11812 1611 1 IfllS 58% 50 50 55% 38ki 72% 48% 8I?4 56*% 75% 51 82% 58 93% 68% 29 46 58 66% 51% 79% 79% 88% 88% 102% 102% HmI%M 112% 112% 21 19 21 22% 45% 27 M 62% 33% 74% 33% 74% 35% 78% 42% 92% Aquamisers Approx. Net Weight Lb 300 Type Capa city Btu per Hour Dimensions-- nches Length Width Height Approx. Net Weight Lb 400 525 EW- 135 350 fl EV - 205 360 ' EV - 275 612 EV- 415 615 1 EV - 550 794 EV - 640 826 EV- 850 915 EV-1320 951 EV -1700 52500 99200 117600 187000 247000 312600 399600 572700 799200 41 68% 68% 89% 89% 115% 115% 117% 117% 28 31% 31% 38% 38% 42% 43% 55% 8336 46% 62% 62% 69% 69% 74% 74% 88% 104 465 719 832 1266 1376 1863 2065 2931 3902 1127 1177 1450 1550 Net refrigerant capacity at 75 F WB entering 1 air and 110 F condensing temperature. HOW TO SELECT--Fit equipment to meet the total Btii load. WHERE TO BUY--Consult classified telephone directory or nearest Westing- house district office for name of Authorized Contractor. ' SELF CONTAINED SYSTEMS Mobilaire Unitaire Specifications Compact, self-contained units for in dividual room cooling in homes, offices, hotels, apartments. Attractive cabinets of modern design and finish. Details available on request. Unitaire Compact, self-contained units for retail stores, restaurants, and other businesses, also for home use. Avail able in either "within-the-space" or "central plant" types. Quick economi cal installation either singly or in combination. Seven sizes. Type CU- 45 SU- 90 SU-135 SU-20S LU-415 LU-550 LU-850 Capacity Btu per Hour Dimensions--Inches Depth Width Height Approx. Net Weight Lb 12000 27580 40800 64500 124400 158100 266000 24 23% 23% 23% t34 t34 J35 38 34% 46% 46% 70% 82% 99% 26 92% 92% 92% 66% 66% 73% 450 1050 1175 1455 2900 3200 420Q Net capacity with normal air flow, entering 80 deg DB 67 deg WB and condenser water inlet 75 F, outlet 95 F +Add 14% in. for overall dimensions with filters. {Add 25% in. for overall dimensions with filters. HOME HEATING AND AIR CONDITIONING A complete line of attractive, efficient heating and air conditioning equipment for oil, coal or gas, in a full range of capac-' ities for all residential requirements. (Below)--RU-90 summer cooling unit for use with winter air conditioning units to form a yearround system. ( A bove) -- Boilerburner units for steam or hot water systems, oil or gas ' fired. . {Right)--Steel and cast-iron gravity warm air furnaces available in 6 models- and sizes. 809 Air Conditioning Central Systems United States Air Conditioning Corporation A Complete Line of Air Conditioning Equipment 2101 Kennedy St., N.E. Minneapolis, Minn. Branch Offices or Agents in Principal Cities U. S. AIRCO Air Washers U. S. AIRCO Blowers Single inlet single width and double inlet double widthBlowers for both supply and exhaust. Sizes from .300 cfm to 100,000 cfm. Single and double stage air washers, ail sizes, from 2500 cfm to 100,000 cfm. U. S. AIRCO Unit Heaters Series 39 Unit Heater with U. S. AIRCO patented Def lecto-Grille, horizontal and ver tical blades both adjustable for per fect control of air volume and air dis tribution. Type A Blower, with backward 1y c u rve d blade impeller. Both single and double inlet. Sizes from 1,000 to 70,000 cfm. Also Standard Model Unit Heaters with adjustable horizontal louvres. U. S. AIRCO--Blower--Filter Package Unit . Also light duty Blowers and Blower- Filter Units for furnaces and self-contained' air conditioners. Also Propeller (Exhaust) Fans. _. U. S. AIRCO Unit Coolers Complete units with blower, drive, motors, filters, furnacestat. Also Blower Assemblies, wheels and scroll housings/ Unit Cool ers for cold water or di rect expan sion. Range of sizes. Send for catalog showing complete line of U. S. AIRCO Equipment. Air Conditioning Central Systems York Ice Machinery Corporation York, Pennsylvania ' Factory Branches and Distributor Engineering and Sales Offices throughout the World. * Air Conditioning and Refrigeration for maintaining proper atmos pheric conditions for human comfort and industrial processes. Installations of unit and central systems in a complete range of capacities and types for every design requirement. York Scclionui A ir Conditioner Yorkaire Hailing Unit York IT-Type Condensing Unit Air Conditioning Units: A complete line of finned coil, dry coil, wetted surface and spray type sectional air con ditioners for horizontal or vertical applications, designed to facilitate installation and the distribution of air. Standard units can be equipped.with by-pass feature and arranged for cooling and dehumidifying, heating and humidifying, for year-round comfort. Yorkaire Heat and Winter Air Conditioning--A com plete line of York equipment is available for residential or small commercial heating and winter air conditioning installations. Direct fired furnaces, and boilers for steam or hot water can be furnished-for burning oil, gas, or coal. Stokers and conversion oil burners complete the catalog. Related apparatus for use with YORKAIRE HEAT units provides complete equipment for yearround air conditioning systems for homes and small business establishments. ` Dehumidifiers--For central station systems where a large volume of air is to be handled and where control of humidity is an essential requirement, the York dehumidi fier is especially applicable. Construction features insure a minimum space demand and maximum performance conditions. Standard washers are available in a full range of capacities for human comfort or industrial instal lation. Air washers can be furnished also for use as indoor condensing water cooling towers when specified. The York Economizer--A combined forced-draft cooling tower and refrigerant condenser, is available for instal lations where prohibitive water costs or inadequate drainage facilities preclude the use of a water cooled condenser. Standard factory constructed and built-up units may be used singly or in multiple for applications of any specified capacity. Economizers for use with the refrigerant Freori-12 are furnished, as standard, with a liquid sub-cooling coil. . Condensing and Water Cooling Systems--Standard systems are available for every application requirement up to 1,000 hp capacity using a single compressor. Self-contained units up to 175 hp feature the YORK line. These units are furnished with water cooled con densers or without condensers for economizer appli cations. Automatic or manual capacity reduction by-pass valves can be provided for economical operation at reduced load. All materials and manufacturing methods employed in the construction of the York Freon-12 Condensing and; Water Cooling Systems conform to the high standards and efficient operating characteristics of all YORK pro ducts and carry performance guarantees based on Refrigeration Manufacturers' Association and Air Con ditioning Manufacturers' Association ratings. 811 Air Conditioning R/RTEMP D/ V/S/OA/ OF CHRYSLER CORPORATION DAYTON, OHIO AIRTEMP RADIAL COMPRESSOR Sttes range from 10 Hp to 75 Hp capacity for individual unit or multiple installation. In self-contained Con densing Unit models for city water or cooling tower appli cation or Compressor Unit models for use with evaporative type condensers. AIRTEMP "ALL-IN-ONE" AIR CONDITIONER The Airtemp "All-In-One" is a complete system, all in one cabinet . . . cools and dehumidifies, filters and circulates, with positive ventilation; for free discharge or duct distri bution of the conditioned air. Heating coil and humidifiercan be furnished for connection to existing heating systems. Compact--Entirely self-contained and all working parts compactly enclosed within a finished metal cabinet. Two sizes and capa cities for single or multiple installation meet all requirements for dependable low-cost air conditioning in stores, shops, offices etc. Model No. 3 SC 5 SC Hp Cp. 3 5 Free Air Delivery cfm 1200 2000 Approx Dimens, (inches) .. L WH 20 89% ' 54 20 971/, Engineered Especially For Air Conditioning. Practically no vibration ... an in herent characteristic of radial design ... all parts balanced. Direct connected ... no belts, no flywheel. Operates at standard motor speeds. Economical--high volumetric effici ency, large gas passages, large valves . and ports, and low friction insures low operating costs at all loads. Forced-feed lubrication for smooth running and long life. Automatic starting unloader permits starting without load. Automatic capacity regulator keeps machine constantly balanced to vary ing load requirements while running- at constant speed . . . economical. Operates at peak efficiency under all loads. Shipped completely assembled . . . easily installed. Write for Bulletin No. L-336. Efficient--Unusually quiet, trouble-free operation assured because of the Airtemp hermetically-sealed Radial Compressor which is suspended from single rubber mounting. Readily Installed--Completely assembled and factory tested . . . delivered ready for installation. Approved by Underwriters Laboratories, Inc. 812 Air Conditioning Direct Fired Units /f/RTEMP " D/ V/S/ON OF CHRYSLER CORPORATION PAYTON, OHIO Model No. 0- 7 0-10 0-13 0-16 0.20 AIRTEMP OIL-FIRED WINTER CONDITIONERS Btu/Hr Output at Bonnet 70.000 100.000 130.000 160,000 200.000 Floor Dimensions (Inches) Length '/, 60 70 73% 69 Width 26 28 35 37 41 Heat, humidify, circulate, and clean the air. One piece copper-bearing steel furnace body. Chrome steel combustion chamber. Beautiful modern insulated jacket. Two-tone finish--stainless,steel trim. Large slow-speed fan. Completely iso lated from firebox and jacket. Model No. 3GF 4GF 6GF 8GF GF-250 AIRTEMP GAS-FIRED WINTER CONDITIONERS Btu/Hr Output at Bonnet 60.000 80.008 120.000 160.000 250.000 1...... Floor Dimensions(Ipches) Length >/, 53% Width 2o M 100. 37% * Heat, humidify, circulate, and clean the air. nace body. * Airtemp silent-flame gas burner. * Beautiful modern insulated jacket. Two-tone finish--stainless steel trim. * Large slow-speed fan: Completely iso lated from furnace bodv and iacket. AIRTEMP BOILERS Steam Hot Water Boiler ' Boiler Model No. Model No. Rating in EDR ,, 1 ,, Su*m 1 Hot Wa"r OS-20. OS-30 OS-40 OS-50 OS-60 GS-70 . oooooo assess (Oil-fired) 400 700 950 1200 1450 1700 640 ISM 1920 2320 2720 Ample heating surtace, quicx lieauiig. Fire chamber surrounded on sides and hottom with water sections. Reautiful modern insulated jacket. . Two-tone finish--stainless steel trim. * Internal Taco heater for domestic hot water. . * All controls and burner completely en- GS-20 . GS-30 GW-20 GW-30 400 635 busfion chamber shaped to fit the flame. GS-40 . i. CS-50 GW-40 GW-50 830 1050 ! . , * Gas-fired boilers use the Airtemp Silent , Flame Gas Burner. AIRTEMP OIL BURNERS Model A-S-t-0.75-to 1.2 gal No. 3 fuel oil per hour. Small, compact, quiet. ' Model 8-9^1.35 to'3.0 gal No. 3 fuel oil per hour. Modern design. With exclusive Twin Airflow and Cushioned Power. Model B-10--1.2- to 2.5 gal No. 3 fuel oil per hour. chromium trim. ' Model C-10--2:5 to 4.5 gal No. 3 fuel oil per hour. chromium trim. ' Beautiful finish in two colors, Beautiful finish in two colors, 813 * _________ . ........... ... Air Conditioning Wrldunits Delco Appliance Division General Motors Sales Corporation BACKED BY ` Rochester, N. Y. Delco offers a complete line of automatic heating products, including: oil burners, bituminous coal stokers, oil and gas-fired boilers, oil and gas fired winter air conditioners and automatic water heaters. Write to Delco Appliance Division, General Motors Sales Corporation, Rochester, N. Y. for latest information and detailed specifications, or consult your local Delco distributor whose address is listed in the classified section of your telephone directory. .. . DELCO AUTOMATIC HEAT Model "A" Oil Burner with Rotopower Unit OIL BURNERS Delco Oil Burners employ the highly efficient pressure atomizing method of breaking the liquid fuel into fine particles for complete combustion. In the Delco Oil Burner with the Rotopower Unit, the motor, air, blower, fuel pump, filter and fuel control valve are all contained within a single, easy-to-remove unit on an integrated shaft. The high-precision pump connecting directly to the shaft of the Rotopower Unit motor has only two moving parts, fitted together within 2/10,OOOths of an inch. Built into the Rotopower Unit is the Thin Mix Fuel Control which regulates the pressure of the fuel oil for proper mixing with air to assure the most economical flame._ Delco Oil Burners are available in 5 sizes in standard voltage character istics with combustion rates from 1-30 gal per hour or a capacity range from 440-12,000 sq ft of steam, EDR. .. '' ' SD-to stoker BITUMINOUS COAL STOKERS Delco Stokers which are designed to provide auto matic .firing for coal-fired domestic heating plants are of the underfeed, screw type with intermittent coal feed. Two 20-pound, two 30-pound and one 50-pound stoker, burning bituminous coal, make up the Delco line. Features incorporated in deluxe models include: automatic controls, air control, Rhino-Hide lined hop per, smokeback eliminator, oversize feed worm, and sound insulation. Fingertip transmission control per mits ease of regulation of coal flow to suit the weather. Coal qontrol consists of two speeds and neutral in 20-pound models; three speeds and neutral iii 30-pound and 50-pound models. Using 12,000 Btu per pound coal, capacity of 20-pound models is 600 sq ft steam EDR, of 30-pound models, 900 sq ft steam EDR, and of 50-pound models, 1500 sq ft steam.EDR. 814 Delco Heat Air Conditioning Direct Fired Units DELCO AUTOMATIC HEAT . BOILERS Delco Automatic Boilers coordinate the Delco Oil Burner or Delco Gas Burner with a boiler of special design and construction for application on hot water, steam or vapor-vacuum heating systems. Most oilfired models incorporate the famous Delco Oil Burner with the Rotopower Unit. Boiler sections are dotted with heat-absorbing fins. When sections are fitted together, fins form a series of passes, exposing a maxi mum of' water-backed surface to the heated gases. Three models, the DSS, the DB-3 and DB-4 incorporate the exclusive Quik-Action Heat Transmitter which provides quick, radiant heating and render the previous slow heating fire clay refractory lining of the combustion chamber unnecessary. Provision is made in all models for incorporating a built-in domestic water heater. Six oil fired automatic boilers, with capacities ranging from 300-1,335 sq ft of steam, EDR, and one gas fired mode! with a capacity of 800 sq ft of steam, EDR, are avail able. DSS-DSW BOILER The latest addition to the Delco line of automatic boilers is Model DS, a new small steel boiler for either steam or hot water with a capacity of 300 sq ft of steam EDR. The Delco Automatic Water Heater, Model DS, resembling the steel boiler in construction and operation, is also available. Model DS employs the Quik-Action Heat Transmitter which utilizes radiant heat 9 times faster than open type flames in refractory fire boxes; the simplified Rotopower Unit that contains all moving parts within a single, easily removed unit on an integrated shaft; the Thin Mix Fuel Control which meters fuel oil economically and prevents waste; and the Heat Trap, a special baffle that conserves heat ordinarily lost. Water chambers of the DS Boiler are of boiler-plate steel tested to 300 lbs pressure. They are insulated with a thick overcoat of rock-wool. CONDITIONAIRS The Delco Conditional is a compact, completely automatic unit, oil or gas fired, which provides true winter air conditioning by circulating cleaned, humidi fied and properly heated air. Model DAO Delco Oil Conditional incorporates the new, exclusive Quik- Action Heat Transmitter. Air flow resistance is reduced to a minimum by tear drop design. Heat is transferred to the flowing air from a large heating surface dotted with heat projectors, and moisture is then added by a pan, cascade or spray type humidifier. A cooling attachment can easily be added for year 'round use. In Delco Gas Conditionairs there is a sufficient range in sizes to permit selection of the proper unit for applications ranging from 85,000 Btu heat loss to 255,000 Btu heat loss. Delco Conditionairs, oil fired, .range in size from 85,000 Btu heat loss'to 280,000 Btu heat loss. . 815 The DSS Boiler The DAO Condilionoir I Air Conditioning Direct Fired Units GENERAL fp ELECTRIC COMPANY AIR CONDITIONING PRODUCTS Air Conditioning and Commercial Refrigeration Department, ---------------------------; Bloomfield, N. J. ------- ^--------------------------- :---- G-E Oil Furnace--Available in sizes from 312 to 1875 sq ft of steam radiation. These furnaces are designed for steam, vapor, or hot water radiator systems and for indirect heating with air con ditioners. Quick steaming, compactness, low standby losses, high year 'round operating efficiency and attractive appearance are the outstanding features of these units. Fully coordinated boiler, burner, domestic hot water, and controls in one enclosed unit made and war ranted by General Electric. Welded steel boilers constructed in accordance with A SME boiler code. Listed by Underwriters' Labor atories, Inc. Automatic night and day temperature control available with all units. G-E water circulator available with hot water furnaces. G-E Oil Burner--Conversion unit for existing or built-up heating systems. Consists of motor-compressor, fan, burner head, and controls enclosed in an attractive gray metal jacket. Flexibility makes it applicable to varying sizes of boilers and furnaces. Tailored flame to conform to fire-box giving maximum efficiency. Models available for steam, vapor, hot water, and warm air systems. Easily installed and serviced. Oil rates from % to 3 gallons per hour. G-E Warm Air Conditioner, Oil Fired--Available in sizes from 100,000' to 160,000 Btu per hour output. These warm air conditioners are of the direct fired type, designed especially for residential and small commercial winter air conditioning systems. They provide clean, warm, moistened air which is circulated throughout the conditioned space. Each unit consists of a combustion heat transfer unit, centri fugal fan, humidifier (optional) filters, controls, and necessary air, oil, water and electrical connections, all enclosed in an attractive chromium trimmed gray cabinet. Automatic night and day temperature control available with all units: Listed by Underwriters' Laboratories, Inc. G-E Warm Air Conditioners, Gas Fired--Horizontal and vertical units. Con sists of combustion heat transfer unit, gas burner, centrifugal fan, humidifier (option al), controls, and necessary gas, water, and electrical connections enclosed in attractive cabinet. Direct-fired air conditioner, de veloped especially for residential and small . .commercial air conditioning, which circu lates clean, warm, moistened air through the conditioned space. Numerous sizes available to meet heating requirements from 35,250--216,000 Btu per hour output, with air flows ranging from 400--2700 cfm. Approved by AGA. 816 General Electric Company Air Conditioning Direct Fired Units G-E Gas Furnaces--Designed for steam, vapor or hot water radiator systems and for indirect heating with air conditioners. Tyne LM ratings from 320 to 1440 sq ft steam; Type LK ratings from 660 to 1760 sq ft steam; Type LC ratings from 1980 to 9680 so ft steam. Automatic pressure, low water and temperature limit con tool Gas regulation is gas operated to assure positive action. Cast iron sectional boilers meet ASME boiler code. Approved by A GA. G-E Unit Air Conditioners--Type FD-- Available in sizes from 134 to 10 hp. Each unit consists of an enclosed sound-proofed con densing unit, water cooled condenser, cooling coil, heating and humidifier coil (optional), fan, filter, adjustable air discharge, and controls, all enclosed in a golden bronze cabinet. Each unit is designed to be installed quickly and easily within the air conditioned space of a general office or small commercial establishment and all the units may be, used as a central system located remotely from the conditioned space. Outstanding features include simplicity in design, easy accessibility, quiet operation, and simple installation permitting easy, re location. ` G-E Unit Room Air Conditioner--Type AF-1 {Above, right)--This unit is designed for comfort cooling applications where cooling, dehumidifying, circulating, ventilating and cleaning of air are desirable. The air conditioner includes a condensing unit, cooling coil, fans, filters, air or evaporative cooled condenser and controls, all enclosed in an attractive walnut cabinet. The unit features high cooling capacity, low operating cost, ease of installation and pleasing appearance. G-E Air Circulator--Types HV1B, HV1D (illustrated), HV2A, and HV2B for attic ventilation, air circulation and exhaust applications. Type HV1D also available with pedestal mounting for air circulation. G-E Condensing Units--Available in sizes from ' 1 hp through 100 hp. Several air cooled models in small sizes; water cooled models with shell-and-coil and truly cleanable shell-and-tube con-; densers. Efficient design provides high cooling capacities. Designed especially for air-conditioning application as part of complete G-E air conditioning systems. G-E Evaporative Condenser--Type GF--Avail able in ten sizes in capacities from 2 to 50 tons. These units are used with compressors to condense refrigerant where it is' desired to maintain minimum water costs. Features include maximum water conservation due to recirculation of water in all units, indoor or outdoor operation, slow speed centrifugal fans, sub-cooling coils,, and easy accessibility to all parts. G-E Central Plant Air Conditioners--A complete line of factory designed air conditioners for summer, winter or year 'round applications. Types HD-50, 100, 200 and 300 units include aphonic radial flow fan, filters, humidi fiers, cooling coils and heating coils in combinations which meet a wide range of air conditioning functions and required capacities. The larger sizes, Types HD-400, 500, 600, and 700 include filters, humidifiers, cooling coils, heating coils, to meet requirements of large, single and multi-zone systems. .(See atso Pages 802-893) 817 Air Conditioning Direct Fired Units Gar Wood Industries, Inc. QofCOxxt AIR CONDITIONING DIVISION 7924 Riopelle St., Detroit, Mich. Licensed Distributors in All Principal Cities TEMPERED-AIRE UNITS The Tempered-Aire heating and air-con ditioning equipment made in five (5) capacities, consists of niters, blower, burner, humidifier, and oil furnace engineered into one compact, coorcfi- nated system. Clean, humidified, warmed air is delivered from the unit to the duct system and then uniformly distributed to all parts of the building. Air is cleaned by dry cloth filters and circulated by a multiple-blade blower fan. The heating unit is a down-draft, warm-air furnace equipped with Cross-Sectional View an integral pressure atomizing type oil burner. The humidifier is a steam tube within the firebox, assuring simple and prompt humidification The new line of Tempered-Aire units (Models 101, 201, 301, 401, 501) have many im provements including the new Model "OC" oil burner and new cabinet design. The oil burner starts, operates and cuts off smoothly even with widely varying draft conditions. Combus tion is clean, quiet and efficient, due to the improved manner in which the air and oil are mixed to make a sunburst-shaped flame. CO* is exceptionally high, and even greater economy than previous models is assured. Tempered-Aire Ratings and Dimensions Btu l Hour at Bonnet............................................................ Btu 1 Hour at Grilles.............................................................. Air Delivery Cfm..................................................................... Air Temperature at Bonnet..................................................... Oil Rate. Ijalkms t Hour............................. .......................... Heating Surface. Sq Ft............................................................ Filter Area. Sq Ft.................................................................... Motor Horse Power-Burner..................................................... Motor Horse Power-Blower..................................................... Overall Length, Inches.................................................. ;.... Overall Width. Inches................................... :....................... Overall Height, Inches............................................................ No. 101 ioo.ooo 80,000 1.000 160" 1.00 54</j 30 1/6 1/5 77 32 54 No. 201 No.. 301 135.000 200.000 110.000 160.000 1350 ' -----2.000 160" 160" 135 2.00 64 86'/. 48 52 1/6 1/6 1/4 1/5 83 89 32 36'/2 54 54 No. 401 300.000 240.000 3.000 160 3.00 120 78 1/4 3/4 104 38 64 No. 501 400.000 320.000 4.000 160" 4.00 160 78 1/4 116 38 64 GAS-FIRED TEMPERED-AIRE UNITS The modern luxuries of Tempered-Aire air condition ing are available to home owners who prefer to use gas fuel. Every Tempered-Aire function is fully automatic. Models 80, 90 and 120 units provide: air filtering, forced air circulation, automatic gas heal ing,* humidifying and blower cooling in summer. The Gar Wood gas-fired units, noted for their generous amount of heat Model ISO ing surfaces and the propor tioning of these surfaces, Model 80 provide long life, maximum effective heat transfer and unusual economy of operation. 818 Gar Wood Industries, Inc. Air Conditioning Direct ' Fired Units Model R BOILER-BURNER UNITS For steam and hot water heating systems. Made in 6 sizes. Model R (3 sizes) is a compact firetube heating boiler with oil burner integral. All models of the B series are internally fired, down-draft, 3-pass construction. Unusu ally efficient. Long flue gas travel. Abundant heating surface. Stand-by losses at mimimum. Tankless coils Model B-iso-w extra with B180 and B270 Model B-180 S 6* W BI20W B160S&W B270S&W R1000S&W Rl400SficW R1800S&W Output KBH (1000 Btu per Hour) Maximum Gross Steam Load--sq ft... . Overall Length--Jacket.......................... Overall Height--Jacket........................ . 1.20 1.20 30 28 48 36 1.80 1.80 500 750 46 26 48 52 2.70 3.50 5.00 6.25 2.70 3.50 5.00 6.25 750 1000 1400 1600 1125 1500 2100 2700 65 84 118 154 26 38 38 38.. 60 60 66 80 52 68 68 ner sq ft at 160 deg temperature multiply by 1.6; for 175 Btu heat emission per sq ft at 180 deg tempera ture multiply by 1.37; for 200 Btu heat emission per sq ft at 200 deg temperature multiply by 1.2. VENTILATOR INDIRECT AIR CONDITIONING EQUIPMENT A silent op Made in eight (8) sizes. erating venti A compact cabinet unit lator--attic or containing cloth air filter commercial and vapor mist filter, use. Consists blower, humidifying of belt-driven chamber, and indirect propeller type blast heater. Designed fan; electric motor with overload particularly for use with protection; metal housing; auto Gar Wood Boiler-Burner matic shutter; insect screen; can Units (steam, or hot vas connection and clamps; sus water), but may be used pension springs. 8 Sizes: 20 in. to effectively with any ade 60 in. Cfm: 3500 to 30,000. quate existing plant. OIL-FIRED WATER HEATERS COMMERCIAL TYPE--An attractive, DOMESTIC TYPES--Model quiet operating bal S50--coil type heater for use with anced unit; 2 sizes. separate storage tank. Cap. 50 Burns No. 3 fuel oil. gal per hour 100 F temperature Fully automatic. rise. Model S40 has storage tank Separate tank. integral. Cap. 40 gal Capacities: 200 per hour 100 F tem and 300 gal per perature rise. Verti hour 100 F tem cal rotary burner, perature rise. Over one moving part. all widths: 28Hin.; For use with No. 2 lengths: 49 in.--61 in. or lighter oil. Model S60 Model S+O CONVERSION OIL BURNER BOILER-BURNER HEATING AND HOT WATER UNIT TYPE A |H] A complete automatic unit to furnish heating and domestic hot water for small homes, stores and individual apart ments. Oil fired. Compact. In expensive to operate. Only 4 sq ft of floor space required. 20 gal hot water per hour. 44,000 Btu per hour net heating load. Total nozzle output 66,000 Btu per hour. aioaei ul, Model "OC" provides stabilized air delivery, unobstructed air travel. Highly efficient for installation in existing heating plants. Pro " vides a Sunburst flame noted for its efficiency. Silent, safe. Fits any shape of firebox, 819 Air Conditioning Direct Fired Units Williams Oil-O-Matic Heating Corporation Manufacturers of Automatic and Manually Controlled Fuel Oil Burners Year 'Round Air Conditioning Systems, Williams Ice-O-Matic Compressors Bloomington, Illinois ________________ * New York, N. Y., 2014 Graybar Building A Complete Line Complete Boiler-Burner Williams Oil-O-Matic offers sixOil-O- Matic burner models--a genuine Williams Oil-O-Matic for every size and type of house, for every and Furnace-Burner Units , Oil-O-Matic burners are also used as an integral part of the following boiler- apartment, public building or commercial structure. burner and furnace-burner units: . Complete boiler burner Abram-Cox Oil-O-Matic, and furnace-burner units; a new typeof oil-burningautomatic water heater; an oil Evans Oil-O-Matic, Inter national Oil-O-Matic, Kruse Oil-O-Matic, Orr & Sembow- OWTICburning range burner for heavy duty ranges are avail able. er Oil-O-Matic, Waterman- Waterbury Oil-O-Matic. Boiler-burner units auto matically provide domestic Heating Capacities of OU-O-Matic Burners' hot water supply the year 'round. Indirect Domestic Shipping Weight Lb 1Length, in. [ ! Width, in. | 1Height, in. J Model K-150 K-3 K-4.5 K-7 j-1800 k_ 125 145 170 175 255 295 Gals. Fuel Oil per Oper ating Hour CL j Mini Maxi X mum mum 29 50 33>A 50 I5K m f/IQ 1600 15M X>H 1/10 1600 20K \% 1600 11" 1800 \n 1800 32 24 1800 2H 4 8 12 1-/Z 41/z 15 25 heating coils may be included. Furnaceburner units provide winter air condition ing. Underwriters' Listing By Underwriters' Laboratories, Inc. Fuel Oil Range Burners Williams Oil-O-Matic fuel oil burners as an integral part of Oil-O-Matic South .Bend heavy duty ranges. Standard draft pipe 18 in. 12-in. length draft pipe optional. - Standard electric current is 110-volt, 60-cyde. Water Heaters Year 'Round Air Conditioning Williams Air-O-Matic provides cooling and dehumidification in summer, heating and humidification in winter, together with WHA* 600 57 22M, 28 i/it 1800 WHBt 885 75 23 WHCt 1385 90 29 28 34 1/10 1800 1/10 1800 .,/l IV, ventilation, air* circulation and cleansing throughout the entire year. This complete year 'round air conditioning is provided Output: 90 F rise, 60 gal per hour. (Output: 90 F rise, 120 gal per hour. (Output: 90 F rise, 210 gal, per hour. by one integrated system. Refrigeration is furnished by a new type of absorption unit, using low pressure How to Decide Size of Burner steam as its source of energy, developed For low pressure domestic boilers, i gal of fuel oil per hour (140,000 Btu) is re quired for approximately: t 300 sq ft of steam radiation or its equiva lent. 480 sq ft of hot water radiation or its equivalent. , 70,000 Btu when using hot air furnace ratings. ` i, 24 Sq ff- steam boiler heating, surface (or 2i2 hp)r : = ; , . specifically to better meet the unique requirements of air conditioning. Both refrigerant and solvent are essentially non- ' toxic, non-explosive, and nonTpombustible under normal atmospheric or normal oper, ating conditions. Air-O-Matic.is an auto matic-fired complete year around tem perature and humidity.control uni .. Air-O-Matic offers , these principal ad vantages: quiet operation; low power' requirement; negligible, deterioration; For exact-detail data, see Oil-O-Matic' Installation and Service Manual. , ' l' - Oil-O-Matic Water Heaters economy of operation and maintenance; and, mechanical simplicity. Low pressures prevailing in the absorption unit minimize the possibility of losing a refrigerant charge 3 sizes cover ordinary home use, large either when the unit is in operation or home and heavy duty requirements. The when idle. Oil-O-Matic oil burner, combustion cham Engineering Service ber, water reservoir, and automatic con Available to architects. See".4. /. A. trols combined in one compact unit. File No. 30.G-I. 820 Air Conditioning rumace Systems Acme Heating & Ventilating Co., Inc. 4224 Lowe Avenue, Chicago, 111. THE ACME HEATER--"It's in the Fins" T. ,, Acme Heater has been designed by experienced heating engineers, and is con , , 'vJl bv expert craftsmen. It combines the best practice in the design of direct transmission heaters, with marked improvements resulting from practical experience. n irns Anv Kind of Fuel: A direct-transmission heater, such as the Acme, is not deoendent upon the kind of fuel used--any type of fuel may be burned. Suitable grates he nrovided so that bituminous, semi-bituminous, anthracite coal, or other solid mav be used with equal efficiency. Replacement of grates.and linings by proper luels may refractory material permits the use of automatic stokers or oil burning equipment. Large Combustion Chamber: Provides ample space for ignition of gases of combustion, regardless of kind of fuel used. The unusually large combustion chamber, acting as "primary" heating surface, effects efficient transfer of heat, because of the great temperature difference be tween the burning gases inside the chamber and the air passing over the outside surface. Phantom View of Acme Heater Showing Flow of Gases and Air Travel. `Physical Data--Large Series Efficient Radiator Section: Although the heating surface of the combustion chamber is large and efficient, still more heat must be extracted to obtain satisfactory .overall efficiency. The "phantom view" as shown reveals how the gases of combustion enter the rear ..smoke chamber, flow to the front of the heater, and return again to the smoke-box. The gases are held in intimate contact with the heating surface, six times the length of the heater, before they are permitted to escape. ' sSize No. Dimensions Lgth width Ht Grate sq ft Heat Surf. sqft Free .Area .sq ft Min. Free Area Wl Lb Max. Capacity Btu * 7 6'-6* 8 8'-1* 9 9'-8' 10 ir-3' 4'-0* 7'-O' 10 31 260 6.55 10.25 5900 900,000 4'jy 7MT 1 .91 34ft 7.71 12.50 7000 1,100,000 4'-O' 7'4T 13.06 430 8.91 14.75 8000 1,300,000 4'-O' Tjy 14.43 500 15.82^22.62 9300 1,500,000 Junior Series 2 4'-6' 3'-6' 5'-8' 3.9 136 4.7 4.7 3200 350,000 3 6'-0* 3'-6' 5'-8' 6.1 183 5.9 6.9 4800 527,000 4 '7'-6* 3'-6' 5'-8' 7 2 230 7.1 9.1 50QU 634.000 5 9*-O' 3'-6' 5'-8' 9.3 280 8.3 11.3 6000 800,000 mote: f or automatic nnng aao ivy0 m ratings given. High Ratio of Heating Sur face.to Grate Aresf: ^he radiator tubes :are covered `.with - extended surfaces, or' fins, typical of those used on indirect heating coils. The long, oval tubes of the radiator pro vide an exceptionally large heating surface which, combined with the surface of the combustion chamber, affords a remarkably high ratio of heating surface to grate area. Balanced Construction of the Acme Heater provides ample free area and allows proper velocity of (})e ajr i0 be heated. Moreover, this air is brought into direct contact with as much heating surface as possible, resulting in the Acme of Efficiency. 821 Air Conditioning Furnace Systems The Henry Furnace & Foundry Company Manufacturers of MONCRIEF Gravity and Air Conditioning Pipe and Fittings--Gravity Furnaces and Air Conditioning Units 3471 East 49th Street Cleveland, Ohio Phone Michigan 9322 Moncrief Aristocrat and "Special" Oil Fired Winter Air Conditioners, made to operate with any standard Gun Type Burner, and Gas Fired Winter Air Con ditioners are available in numerous sizes and capacities. Coal Fired Cast and Steel Air Conditioning Units are made in various sizes. Data in complete catalog form. Write for particulars. Aristocrat Oil Fired Air Conditioner "SPECIAL'* OIL FIRED AIR CONDITIONERS Unit No. Size of casing: Width........................................... Height ........................................ Cfm.............................................. No. filters 13 z 25........................ 75 .76 28* 7r 60V8* n6 1/6 6120 915 2 75.000 100 1.02 28* 71* 603/g* 112 '/* 6120 1225 2 100.000 Aristocrat . Gas Fired Air Conditioner Approved by American Gas Association SIZES, CAPACITIES--Aristocrat Gas-Fired Units. Unit .Number. AGA Btu Input Per Hour Btu Output Per Hour . | Blower Size Motor Hp* No. of Filters |j Filter Size 140 Reg. Temp. Cfm. Sq In, Heating Surface Gas Line j| No. of Burners |j | Flue Size | Casing Dimensions, In. Plenum Size, In. Warm Air Cold Air A B C D E K. L M N G- 8 G-12 M Vi 26 56V4 w< 7<A 9'A Wi 12 18 30 30 12 18 18 18 G-16 G-24 vTfkfi 34 49 56V, 56'/, 7^4 Wi 24 34 30 32 24 34 18 19 80,000 120.000 160.000 240,000 64.000 96,000 128.000 192,000 no v 112 112 yy.. 114 Vi 2 16x25 857 5410 1* 3 16x25 1285 8115 1* 4 16x25 1714 '10820 1* 5 16x25 2570 16230 IV,- 2 6* 3 7* 4 8* 6 2-7* *Be sure to specify characteristics of gas and electric current available. 822 Air Conditioning Fart Furnace Systems Jjhe MjyER Furnace GhMPANy Peoria, Illinois Manufacturers of Heating and Air Conditioning Equipment for Coal, Gas and Oil Burning Branches and Distributors Kansas City, Mo. Omaha. Neb. Green Bay, Wis. Pittsburgh. Pa. Philadelphia. Pa. St. Louis, Mo. - Columbus. O. Minneapolis, Minn. New York. N. y. Atlanta, Ga. The WEIR Air Conditioner for solid fuels (hand or stoker fired) embodying the famous WEIR Steel Furnace is a complete unit for winter air conditioning, including air cleansing, humidifying and forced circulation as well as heating. Encased in furniture steel with baked enamel finish. Automatic con trols for dampers, blower, humidifier. WEIR Conditioned Air Unit WEIR Gravity Heater No. Grate Surface (Sq Ft) Ratio Htg. to Grate Surface Smoke Outlet Dtam. (In.) - Gravity Circulation . Fan Circulation Casing Dimen. Rated Output Round Rectlar At Reg. Pipe Area (In.) (In.) (Btu.Hour) & In.) Casing Air Rated Output Dimen. Delivery at register (In.) . (CFM) (Btu. Hour) 621 1.26 624 1.78 628 2.32 630 3.08 633 3.82 636 4.74 6.25 544 7.60 41.2 33.9 29.2` 26.4 22.7 19.4 19.3 18.5 9 10 10 10 10 10 12 12 48 54,400 52 47x50 73,600 54 50x52 94,100 58 54x56 119,060 65 56x64 138,000 67 56x66 160,000 400 541 47x90 1200 692 50x99 1600 875 54x103 2000 1015 56x110 2300 1180 56x118 2700 58x108 6100 92 000 118*000 148 000 172^000 2001800 360,000 WEIR Oil Fired Air Conditioner The WEIR Oil-Fired Air Conditioner does a complete job of winter air conditioning. Designed for oil fuel and forced circulation. Completely self-contained in low compact casing enclosing burner and blower as well' as heater and all controls, yet with everything easily accessible. The MEYER Gas-Fired Air Conditioner automatically provides completely controlled winter air conditioning. Efficient perform ance, compact design, modern appearance. Heavy gauge welded steel heating section; die-formed furniture steel casing. A.G.A. approved. No. Input Output at at Burner Bonnet (Btu/Hour) (Btu/Hour) Vent Dtam. (In) Dimensions W. L. H. (In) (In.) (In.) Air Delivery `/sln.S.P. (CFM) Motor Size (HP) MEYER Gas Fired Air Conditioner A-I00-M A-I25-M A-150-M A-175-M A-225-M 140,000 165.000 212.000 260.000 335.000 WEIR Oil-Fired Air Conditioner 110.000 140.000 165.000 195.000 . 250.000 6 25 71 48 8 48 68 48 8 32 78 48 8 56 68 48 8 63 68 48 MEYER Gas-Fired Air Conditioner 1300 1700 1950 2300 3000 1/4 1/3 1/3 1/3 1/2 F-10 (10.000 88,000 5 F-15 165,000 132.000 '6 F-20 220.000 176,000 7 F-30 330,000 2S4.000 9 F-45 495,000 396,000 10 32 69 48 41 69 48 53 69 48 69 69 48 97 69 48 1200 1800 2400 3600 5400 1/4 1/4 1/3 1/2 3/4 MEYER Gravity Gas F urnace MEYER Gravity Gas Furnace J- 90 J-135 J-1S0 J-225 . 90.000 135.000 180.000 225,000 67.500 101,250 135,000 168.750 -4 5 2-4* 1-4*. 1-5* 32Vi 60y$ 74Vi 30 - 30 30 30 47'A 47Vi Complete descriptive literature, including data on Summer cooling, upon request The MEYER Gas Furnace--Efficient--Economical--A.G.A. approval. 823 Branches St. Louis Memphis Omaba Minneapolis Salt Lake Crrr Dallas Air Conditioning Fan . Furnace Systems L. J. Mueller Furnace Co. Established 1857 2009 W. Oklahoma Ave., Milwaukee, Wis. Branches Los Angeles Kansas Crrr Baltimore Philadelphia Pittsburgh Cbicaoo SERIES "O" OIL-FIRED AIR CONDITIONING UNIT The basic, patented design of this Mueller unit secures a new standard of efficiency and fuel economy. The air passes over heating surface not once, but three times. Velocity and impingement create a rate of heat transfer impossible in previous designs. The silent fan supplies generous volumes of warm, humidified, filtered air to secure uniform temperatures. The Mueller Oil Burner is of pressure atomizing type, specially designed for use with this unit. Details of construction and method of operation of the complete unit are shown at the right. Available in three sizes to handle most residential requirements. CLIMATOR FAN-FILTER UNITS For positive distribution of air in old or new construction, wherever air is to be moved, there is a Mueller Climator Fan-Filter unit available. Fans are designed in. accordance with the latest aerodynamic principles. Filter area is adequate to handle the air delivery requirements. Climator fans are available in sizes ranging from 10 in. to 24 in. wheel diameter, and twin fans in 18 in., 21 in. and 24 in. wheel diameter. t j J. Mueller Furnace Co. Air Conditioning Furnace Systems Mueller Heaters For All Fuels A Complete Line for AH Purposes Return Flue all-cast Fur nace. 18 in. to 30 in. firepots, single and double firedoor styles. Available in round, galvanized or square, lacquered casings. Mueller Steel Furnace, with fan-filter unit. Also avail able with round casing. Seven sizes, 20 in. to 34 in. drums. Heavy construction. Riveted and welded. Gas Era Unit Heater. Available in sizes from six to twenty sections, with AGA output ratings from 216,000 to 720,000 Btu per hour. Gas Era Cast Iron air conditioning furnace. A GA input rating, 65,000 Btu per hour, per section. Wide range of sizes and air delivery capacities. Gas-fired air con ditioning furnace. AGA input rating, 45,000 Btu per hour, per section. Wide range of air deliveries. Muelleraire unit. Gas-fired with fan, filters, and humidi fier. 5 sizes--AGA input ratings, 72,000 to 180,000 Btu per hour. Series "AE" Gas Boiler. AGA rat ings, 180 to 1,260 sq ft steam; 290 to 2,015 sq ft hot water. CLIMATROL AIR CONDITIONING FURNACE Enclosed in the compact, ultra-modern cabinet are the furnace, fan, humidifier and filters, together with controls for automatic operation. Heat is supplied by Mueller gas-fired "HeatSpeedert' sections. The powerful Mueller fan provides positive circulation of conditioned air toall rooms. Available in five sizes, providing a range of capacities capable of handling practically any residential requirement. 824 Series 50 oil-fired air con ditioning furnace. Avail able with or without bur ner. Made in one size, 100,000 Btu per hour. Series "SA" stoker-fired furnace, with fan-filter unit. Any stoker may be used. Capacities, 110,000 and 175,000 Btu. Horizontal Tubular Heaters, for schools, churches and other large buildings. Three sizes, with cap acity range from 1,188,000 to 1,390,000 Btu per hour. Complete catalogs on each of above units available upon request. 825 1 Air Conditioning Furnace ____________ ______ ' Systems Pocahontas Fuel Company Incorporated Stoker Division 1190 East 152nd Street, Cleveland, Ohio The "O.P." Winter Air Conditioner is a self-con tained revolutionary unit combined with the famous "O.P." Completely Automatic Ash Removal Stoker. Special features include many important innovations. (1) Built-in radiator. (2) All heat transfer surfaces exposed to the direct radiation of the fire for extremely high efficiency. (3) All heating surfaces vertical to avoid the necessity for cleaning. (4) Surfaces easily accessible through the fire door at the front of unit. (5) Large insulated fire door hinged at bottom for easy disposal of all combustible rubbish. (6) Blower and filters located in separate compartment above stoker. (7) Floor space occupied held to a minimum. (8) Coal feed enters casing at rear. (9) Ash delivered into rectangular containers located in waterproof and dustproof receptacle at side of heating plant. (10) Controls and fireproof electric wiring contained in the casing. (11) Easy access provided to blower and stoker mechan ism by means of removable panels. CROSS SECTION OF "O.P." AIR CONDITIONER Humidifier Warm Air Ovtid Heal Chamber Radiator ' Fire Door . Refractory Segmental-Retort Ash Receptacles Input--15, 20 or 30 lb coal per hour. Maximum rated output --250,000 Btu per hour. Ratio of grate area to heating surface, 30-1. Combustion chamber, ^fg-in. corrosion-resistant steel, brick lined. Controls--MinneapolisHoneywell. Inlet area--750 sq in. Outlet area--1,050 sq in. General Specifications S26 Blower--14 in., 2,000 cfm. ' Maximum bonnet tem perature--180 deg. Filter area--1,600 sq in. Fire door size--12 x 16 in. Motors--Stoker--3^6 hp Repu Is i on - induction Blower--% hp Capacitor. Humidifier--Auto matic float type with evaporator plates. Air Conditioning Unit Heaters and Coolers Airtherm Manufacturing Company 710 S. Spring Ave., St. Louis, Mo. THE ENGINEERED LINE OF UNIT HEATERS AIRTHERM IMPROVED UNIT HEATERS are backed by thirty years experience in unit heater construction, and are recognized for their many new, and exclusive features. Sound engineering principles, highest quality materials and workmanship, plus modern design and styling make Airtherm Units the logical choice. It is significant that most sales of Airtherm Heaters have been made to those concerns maintaining engineering staffs of their own, many of whom are engaged in heating and allied industries. THE AIRBLANK.ET. Propeller Fan Type . . . with a patented method of air direction control to hold warm air in the heating zone. THE AIRBLANKET. Centrifugal Fan Type . . . with the exclusive Airblanket Principle. Airblankets are designed so that a stream of cool air of high velocity is delivered just above a stream of warm air at less velocity. The cool air stream retains and distributes the warm air stream in the lower portions of a building, pre venting unnecessary heating above the breathing level ... it thus produces an artificial ceiling or blanket of cool air above the breathing line. . THE DIRECTHERM. Newly De signed Direct-Fired Unit for Gas, Oil or Coal (Hand or Stoker). ENGINEERING SERVICE. The Airtherm Manufacturing Company Engi neering Department and District Repre sentatives are at all times available for consultation. At your request we will place experienced engineering aid at your dispo sal. Representatives in all principal cities. THE AIRHEATOR. The Airtherm blower fan type unit heater for floor or ceiling mounting. THE AIRVECTOR. (Not illustrated). A propellor type fan unit for ceifing sus pension or for mounting from the floor on recirculation stack. AIR-VENT EXHAUST FANS For Dependable, Efficient and Economical Service Designed to meet Industrial and General requirements for a rugged, heavy-duty type fan. Write for literature and prices. 827 Air Conditioning Unit Heaters and Coolers Fedders Manufacturing Co. HEAT TRANSFER SPECIALISTS SINCE 1896 Manufacturers of Unit Heaters, Heating and Cooling Coils, Air Conditioners, Unit Coolers, Refrigeration Valves, Etc. 85 Tonawanda Street, Buffalo, N. Y. Sales Representatives in All Principal Cities I- FEDDERS UNIT HEATERS Manufactured under one or more of the fol lowing U.S. Patents--1.726.725--1,754.642-- 1.76D.707--1.070,105--2,025.426--Others Pending. Exclusive Full Floating Element Mountings, aerodynamically correct streamline tubes, non-clogging fins, handsome mono-piece cabinets make Fedders Unit Heaters ideal for com mercial as well as industrial instal lations. Built in a complete wellgraduated line ranging from 75 to 1100 EDR, see table at right. Write for Catalog 573G. NHMuUemonadbtieteerlr ESMSmSTqpoLueDetOnieopQdtrr sMSRtSpoPLoetOMeoodrr SOr*9a. ftttitnzngasi A EDR B/HTrl) C70F*MF. Final CU/Hcnnrd.. O/MFuittale.t SMSHTSpoJOLetOeoa.dr 3023 ITS iso 3141 TO ISM 3143 TO ISM 3181 TO UM 3183 CTO SLO3211 rro 3261 3273 33S3 SSrSTTrLLLoOOOOO 3311 3374 SSTLLOOO SLO3372 ' rro 3451 3411 SSrTLLrOOOo 3421 3563 3564 3662 3653 3663 SrCSSTrLLLTToOOOOOO SSrTrLLoOOO 3752 rro 3772 3776 3862 rSSESrLLTToOOOO . SLO3873 rro ISM U4S UUCSMMCMO *UUMMMM00 UUUUH0MMMMM0OO0 UM UUUUUUUU00MM000MMMMMM0MMM000000 UMMO n It.CM MS XS7 IM KM no 1ST 123 MAM s US ISO SCAM tn US ITS 42,0M MS in natMmMsosS0o mmtmIMtIMsMMOo S1MSi7sSnIS0a3S Cmm4MM MnCoM3 nnMt1ooo3o0 UCMM (M0M..00M0M0 MCtMStAIMAAAMMMMM IMHS7AAA.MMMM0 U0MM0S0.AAAA0MMMMN MAM (ISAM IMAM IMI1IIIMMMM3SSOAAAAAAAMBMMMMM0 . IMAM m*aS' IMAM CCSIMMS MSnMsS tM n UuIUSUSOsMMMMMMo MIiI1ISsSM4M4MMn00 UM mmso mMMo 5IUMISMSMMS5MMMOS UU11S2*3S433* 1UIUtnlSs2SsSS2o3 uiSbSsI us1I1I111SMS2*32n*O07173 iURtU1a3S7S7 U3I1S21SS43 u 2S 31 * 43 aM35K4M74 U113i1111nH*a2n34a747U013*32314700733790 i1XItSMn4MS0 2aI70tMl41S010t ns 1/lM no 1AM US LOO ns 1AM tso MS msns. mSMniuo tMMMlIl1///m/MMM3O20l 44I4C73SCUmS312474TMMOS3040S0O 1UU4M7444TnMnCO3021*SSso0SO03O90 inTMOSO, 1ISt3s0 M1MMMMl1///M11SOSS733 M1tMMMM1M1MliI//A////00I0tSSl***lIll t11MMI1/i//S441tI HEATING AND COOLING COILS, AIR CONDITIONING UNITS Complete lines of heating and cooling coils as well as air conditioning units are cata loged on a standard basis to simplify engineering and installation. - Fedders Air Condi tioning Coils with re frigerant Flow-Control Valves make it possible to adjust each circuit of coil to fit exact oper ating and load con-, ditions. Write for Bulletins giving complete physi cal and capacity data. .. Fedders Air Conditioning Units Model No............ I9I-HL 321-HL 522-HL 723-HL II52-HL 1582-HL &Tons refrigeration EDR................... Ci.m............. . 600 1-5 375 1200 l'/2-9 650 2000 2-12 950 3000 3-19 1400 4400 5-25' 1850 6000 6-30 2200 6800 828 Air Conditioning Unit Heaters and Coolers F. Jaden Manufacturing Co., Inc. Established J 914 . Hastings, Nebraska Kfrgjk RIR. CONDITIONING SPECIALISTS IN WATER COOLED AIR CONDITIONING Unit Conditioners (Shown at Left) These models applicable to any cooling installation--large or small. Unsurpassed efficiency--sturdy construction. 50-100 per cent fresh air recommended, assuring complete ventilation and odor elimi nation. For heating, steam coils can be furnished on Universal and Imperial units, or circulating hot water may be used with all models. ARISTOCRAT JUNIOR timiimmu UNIVERSAL FURNACE TYPE CENTRAL PLANTS Three models designed for use with gravity hot air furnaces. Provides complete summer and winter con ditioning, including winter humidi fication. CENTRAL PLANTS Designed for larger installations employing extensive duct systems. Two standard models--specials quoted on request. CENTRIFUGAL UNIT HEATERS Designed for installations requiring silent operation. Ideal for use with duct systems. FURNACE TYPE CENTRAL PLANTS UNIT HEATERS DELUXE ATTIC VENTILATION Designed with centrifugal blowers to insure positive displacement of air. Easily installed--sturdy-- silent. ATTIC VENTILATION IMPERIAL BLOWERS Complete lineof high quality cabinet, base type, utility and twin blowers. 16 gage welded construction--bronze bearings--ground steel shafting. /ire or Write for Complete Details 829 BLOWERS Air Conditioning McQuay, Inc. 1602 Broadway, N.E., Minneapolis, Minn. MANUFACTURERS OF AIR CONDITIONING EQUIPMENT Branches in ail Principal Cities Air Conditioning, Blast and Refrigerating Coils; Convec tion Radiation, Air Condi tioners, UnitHeatersandCoolers. Comfort Coolers Sus pended and Floor Type Blower Coolers, Cabinet Floor Type Room Coolers, Ice Cube Makers, Evaporative Condensers, In door Cooling Towers, the "Zero-Pak" Locker Room Units and "Icy-Flo" Ice Accumulators. THE EXCLUSIVE McQUAY FRICTIONALBOND FIN-AND-TUBE COIL ASSEMBLY The use of the exclusive McQuay Fin and Tube assembly in all McQuay coils and cores is chief among the reasons McQuay products are high in "over-all efficiency." Heat transfer depends in great measure upon the "area of contact." In McQuay coils and cores, tubes are hydraulically expanded by an exclusive process under high pressure to form a permanent bond between tubes and fins. This process auto matically checks all tubes for the most minute defect of strength and quality. Fin and tube contact is accomplished without the use of other metals and results in a maximum of thermal transfer with uniform capacity throughout the McQuay Frictional Bond entire length of the coil. Fins remain flat, straight and uniform and keep air resistance at a minimum McQuay Convectors Designed for reliabilty, efficiency, beauty and cleanliness. Exposed, recessed and concealed enclosures have pteasing lines and rounded corners to harmonize with interiors. The heating element is a series of round seamless copper tubes to which are attached smooth copper fins. Made with a spun collar and the McQuay Frictional Bond by means of hydraulic expansion of the tube into the collar. A per manent bond between tube and fin unaffected by expansion and contraction. . Constructed from high grade furniture steel, eleven indi vidual types, three styles of grilles. Special designs if required. Catalog No. C-439. Cooling arid Heating Coils and Air Conditioning Coils Air conditioning coils are constructed for high pressure operation. Continuous plate type aluminum fins attached to heavy gauge seamless drawn tinned copper tubes. The exclusive McQuay frictional bond is used. Coils for cooling or heating with water can be designed for heating with steam so that a single coil will serve both purposes and may be used for year-round air conditioning, thereby reducing the cost of a complete installation. Water Coils--For cooling or heating with water. Durable high pressure continuous serpentine construction. Wide range of sizes and capacities. Serpentined for maximum efficiency. Direct Expansion Coils--For cooling with direct expansion Removable Plug Coil refrigerants. Equipped with McQuay distributing headers to . insure proper distribution of refrigerant to all tube circuits. Wide range of sizes. Listed as standard by the Underwriters' Laboratories, Inc. . Type RP Removable Plug Coils--For cooling or heating with water. Non-ferrous removable plugs at both ends of all tubes provide easy access for internal cleaning. A more comprehensive description, physical data and coil selection charts are available in McQuay's new Catalog No. 289. 830 McQuay, Inc, Air Conditioning Unit Heaters and Cooler's . Large Type Air Conditioning Units . Suspended and floor types. Cool, dehumidify, filter, and circulate air in summer; heat, humidify, filter and circulate air in winter. Interior of housing treated with sound dead ening insulation to insure quiet operation. Cooling capaci ties from 3 to 50 tons in both Suspended and Floor Type. Send for Catalog No. 85. Suspended Type Steam Heating (Blast) Coils High pressure construction throughout. Primary surface of in. o.d. seamless drawn commercially pure copper tubing, spaced on centers. Staggered arrangement of tubes on coils having more than one row of tubes deep per section. Secondary surface of special flat, smooth,, uniformly spaced straight copper fins. Each fin runs continuously across full width of coil. A wide range of sizes and types makes it possible to select a standard McQuay blast coil for practically any installation which will exactly meet requirements. Easy to select, light weight, durable, compact, efficient, and readily installed. Catalog 250 includes information for selection and installation. McQuay Comfort Coolers Made in two types--one for use with water or brine; another for freon or methyl chloride. Each type built for the specific cooling medium. Eight sizes in each type--all with 4-speed motors and 4-speed manual controls. Note: Comfort coolers using water or brine are com bination cooling and heating units. All such models can be used with hot water and only two cannot be used with steam. Catalog No. 81 for coolers designed for water or brine, Catalog No. 82 for freon or methyl chloride. Comfort Cooler Air-Conditioner Air Conditioners--Cold Water and Freon Types Choice of recirculation of indoor air, entire intake of out side air, or a combination of both. Cold water or brine used in one type; freon or methyl chloride in another. Each type built for a specific cooling medium. No compressor required in localities where water at proper temperature is available. Catalog No. 83 for air conditioners using water or brine, Catalog No. 84 for freon or methyl chloride. Unit Heaters and Coolers McQuay Unit Coolers provide uniform refrigeration throughout all portions of walk-in coolers, storage rooms, beer keg storage rooms, and all types of fixtures where forced air circulation is desirable Standard and "H" type unit coolers are built for standard refrigerants like freon, methyl chloride and sulphur dioxide, unit coolers for ammonia systems available at no increase in price. McQuay Unit Heaters have an all-copper heating ele- encased in attractive cabinet having rounded corners and deflecting louvers, individually controlled. Stainless ?tee* Brown baked-on wrinkled enamel. Heating element is cradled in cabinet permitting expansion and contraction. One integral welded unit, McQuay frictional bond insures i'nii Healer maximum heat transfer in the fin and tube assembly. Wide range of sizes with motors to meet all electrical characteristics. Catalog No. 738. ' 831 ' Air Conditioning Unit Heaters and Coolers Modine Manufacturing Company Heating and Air Conditioning Division General Offices: 17th and Holburn Sts., Racine, Wis. Factories at Racine, Wis. and La Porte, Ind. Branches in all Principal Cities Complete, information on the following products including engineering data and prices, can be secured by writing to the Modine General Offices at Racine, Wis consin--or by communicating with nearest Modine representative. MODINE UNIT HEATERS Unit Heaters--Capacities and Dimensions (In inches) Model No. Over all Height width Depth Less Motor E.D.R. C.F.M. Motor R.P.M. 66 104 140 172 206 252 304 362 414 514 606 711 608 904 1050 1200 1380 1610 2030 \16w3/.' 163/.' l9'/2' 22'/,' 22'/?' 22Vz' 24' 22*/z' 273/2' 27'/2' 27>/2' 29/,' 29<ff 33%' 33J/.' 33' 30* 30' 10* 14'/.' 14'/.' 14'/.' 19' 19' 19* 19" 19* 23' 23' 23' 26'/i' 26'/2' 2&V2' 2S'/2* 34' 50>/,' 543/.' 6' 9* 9' 9' ir M' 11' ir ii' M'/j' 11'/;' M'/i' 13' 13' 13' 13' 11' 11' II' 66 104 140 172 206 252 304 362 414 514 606 711 808 904 1050 1200 1380 1610 2030 227 350 540 661 843 980 1290 1450 1370 2250 2440 2430 2760 3370 3770 4120 4960 5920 7720 1580 1580 1580 1580 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 1120 Front View Bock View The New Modine Unit Heater incorpo-. rates in its design, many features which contribute to more satisfactory and eco nomical industrial and commercial heating. All above models are available with variable speed motors. Units for hot water application also available. MODINE VERTICAL DELIVERY UNIT HEATERS Modine Ver tical Delivery Sound Silenced--Interior surface of casing is coated with acoustical-mastic, deadening noise from within. Venturi fan shroud, integral with casing, quiets air in-rush sound. Velocity generator elimi nates air-rush noise peaks. Concentric rings of fan guard act as vibration dissipators. Unit Heaters are indicated wherever con ditions call for more directly downward de livery of air than is provid ed by the con ventional de Safety Fan Guard--Provides staunch, steel safeguard again hazard of unshielded fans. Safety is built in as standard equip ment. Protection Against Rust--Available by Bonderizing--When applied, Bonder izing of casing and sheet metal parts makes them resistant to formation and progress of rust. It holds finish to metal, making it more durable and permanently fine in appearance. sign of unit heaters. In factories where high clearance is essential, as for craneways, Modine Verticals serve excellently. Over store and office doorways, they fit perfectly into the need for a blast of warmed air to offset the in-pressing winter gales. In a room where only one unit heater is needed, the Modine Vertical gives delivery of heat to the entire perimeter of the room. Or by adjustment of the Modine Cone-Jet Deflectors, this delivered air may be concentrated in limited di rections, even checked almost entirely to And These Additional Features-- (1) Velocity Generator gives greater heat throw without increasing power require ments. (2) Patented Expansion Bend per mits tubes to stand extreme expansion. (3) Direct Pipe Suspension permits instal lation without hangers--saves cost. a single side of the unit. Similarly, multiple installation of Modine Verticals may be controlled as to heated air deflection so as to give more delivery of heated air to outside walls, thus conforming to normal heating require ments. Modine Verticals are made in eleven models. Write for catalog. 832 -'.Modine Manufacturing Company Air Conditioning and Coolers' MODINE COPPER CONVECTORS (Standard Type) The popular copper radiators for com mercial and public buildings, low cost ' bouses, etc.--wherever the benefits of copper convector heating are desired. At tractive enclosures with removable fronts. Wide selection of grilles. Rust protection of enclosures available by Bonderizing. High capacity copper heating units. Enclo sures are made in three types of Recessed and Floor and Wall Cabinets and Concealed (plaster-front) types. Cata log 239-A. (Institutional Type) Designed for use where special construc tion features, common to institutional heating, are specified. This line incorpo rates many fea tures which have heretofore been considered "ex pensive spe cials." Available in two types of Recessed and in Floor and Wall Cabinets. Cata log 239-A. MODINE BLAST HEATERS Made in over 250 sizes, types and ca pacities to meet the specific demands for heat transfer ser vice. Outstanding featuresare: (^Ex pansion Bend. (2) All steam carrying passages are cylin drical for greatest possible strength. (3) From inlet to outlet condenser is of copper or copper alloy. (4) Copper fins are bonded metallically to tubes. Cat. 338. MODINE COOLING COILS For use in central system cooling and air conditioning plants, Modine Cool ing Coils, Cold Water Type, are installed with ;a blower fan and duct work. Adapt able where cold water or non-corrosive brine is used as the cool ing medium. Coils have cleanable tubes. UNIT COOLERS (Blower Type) For stores and offices. This unit.cools, cleans, dehumidifies and circulates the air. Equipped with powerful, yet quiet blower, extra deep cooling coils and large-area air filters. May be installed with or without duct work. Choice of cold water or Freon cooling coils. Bulletin 438-A. AIR CONDITIONER (Apartment House Type) . A compact unit performing every func tion of complete winter and summer air conditioning--for apartments, hotel suites, residences, offices, and shops. Its com pactness allows installation in a closet above shelving or in a hall above a false ceiling. Uses steam or hot water for heating; cold water or Freon for cooling. Two sizes. Bulletin 638-B. AIR CONDITIONER (Large Ce . For residential and commercial year-'round air con ditioning--may be used in straight air conditioning or split systems. Uses steam or hot water for heating and cold water or Freon for cooling. Catalog 639. Type) 833 Air Conditioning w Co"e?srs McCord Radiator & Mfg. Co. Heating and Air Conditioning Division Detroit, Michigan UNIT AIR CONDITIONER A new develop ment to heat, cool and condition stores, large offices and small fac tories. Cooling capacity 5 tons with 45 deg water; heat capacity 77.000 Btu per hour. Two 2 speed squirrel cage fans; silent vibrationless motor; washable spun glass filters. Smart modern design cabinet of chrome trimmed lacquer over bonderized steel. VERTICAL TYPE UNIT HEATER Developed to simplify the pip ing layout on high and wide build ings. Warm air taken from top of building is re heated and dis charged downward into working area. Adjustable deflector outlets provide ef ficient distribution in any direction, re quiring fewer units. Capacities from 115.000 to 250,000 Btu per hour. Totally enclosed ball-bearing motor. UNIT HEATER Advanced de sign permits rear entry of inlet and outlet, eliminat ing unsightly con nections and re quiring small head room. Wide range of output-- Capacities from 20,000 to 500,000 Btu per hour. . Quiet, totally enclosed motor. Beauti fully designed welded steel case with rounded comers, stainless steel mouldings and baked crystal enamel finish. CENTRIFUGAL BLOWER HEATER For use wher ever a large vol ume of air at low face velocity is required. Cap acities 120,000 to 900,000 Btu per hour. Extremely quiet with large voIumew of air. Low speed, large diameter fan may be used with any type of duct construction or with hood as illustrated. OTHER McCORD PRODUCTS McCORD CENTRIFUGAL BLOWER UNIT HEATER--for use where ceiling suspension units are not desirable, particularly where ceilings are high. Floor or wall mountings. McCORDFIN BLAST HEATING AND COOLING UNITS--in con venient standard sizes. Solid copper and bronze, solder dipped, protected Against corrosion and electrolysis. Greater efficiency due to perfect metal to metal contact and reduced air resistance. McCORD SUSPENSION TYPE AIR CONDITIONING CONVECTORS--modem attractive design, sturdy construction, efficient operation. McCORD CENTRAL SYSTEM AIR CONDITIONERS--complete units for in stallations requiring 3 to 24 tbns'cooling and 160,000 to 500,000 Btu per hour heating. McCord maintains one of the best equipped heating transfer laboratories in the industry. McCord's 34 years of experience and progressive engineering will help you maintain your reputation. * *. For engineering recommendations, catalogs, and prompt quotations, write McCord Radiator & Mfg. Co., Detroit, Michigan. 834 Air Conditioning Unit-Heaters and Coolers The Herman Nelson Corporation General Offices and Factories at Moline, Illinois Soles and Service Offices in the Following Cities: ortlaND. Me. Ioston. Mass. Westfield, Mass. Jew York, N. Y. Vatervliet, N. Y. iYRACUSB. N. Y. Johnstown, Pa. Detroit, Mick. Grand Rapids. Mich. Cleveland, Ohio Cincinnati, Ohio Toledo, Ohio Washington, D. C. Memphis, Tenn. Indianapolis, Jnd. Chicago, III. Milwaukee, Wis. Moline, III. Peoria, III. St. Louis, Mo. Omaha. Nebr. Oklahoma City, Okla. Dallas. Texas Missoula, Mont. Denver, Colo. Salt Lake City, U. Spokane. Wash. Richmond. Va. Kansas City, Mo. Seattle, Wash. Roanoke, Va. Charlotte, N. C. Nashville, Tenn. The variety of products manufactured by the Herman Nelson Corporation and their adaptability to many functions, Emporia. Kans. Minneapolis, Minn. Des Moines, Ia. Portland, Ore. Los Angeles, Cal. San Francisco, Cal. Air Conditioning Furnace will provide most satisfactory results. Where radiation is preferred, the Oil Burning Boiler may be makes possible the specification of Herman used and, in combination with the Year Nelson for the heating, ventilating and Around Air Conditioning Unit, will pro air conditioning requirements of industrial, vide the advantages of circulated, con commercial, residential and public build ditioned air to selected rooms of the home. ings of all types. For Public Buildings such as Libraries, Industrial areas may be comfortably Churches, Club Rooms, Schools, Waiting and efficiently heated with hijet Heaters. The Propeller-Fan type is designed for the maximum of heating efficiency as well as long life and quiet operation. The BlowerFan type is available to provide large capacity heating with or without the intro duction of outdoor air. Commercial buildings too are well adapted to the installation of PropellerFan type hijet Heaters. The heating efficiency, low installation cost, quiet operation and attractive appearance of the hijet make it a most suitable unit for stores, offices, showrooms, garages, etc. For locations where a large heating capa city must be concentrated in small space, Rooms, etc., proper heating and venti lation may be provided with the new Herman Nelson Air Conditioner for Schools. Thisequipment maintains desired room conditions at all times---prevents overheating--eliminates drafts, and is par ticularly applicable for areas where large groups of people gather. For auditoriums, gymnasiums, theaters and similar large areas, the Auditorium Unit should be specified. In locker rooms, natatoriums, etc., the DeLuxe Unit Heater or hijet Heater may be used successfully. The ventilation of toilets and laboratories may be quickly and positively performed with the Exhauster. the DeLuxe Unit Heater may be used. The DeLuxe Unit Heater provides con trolled heat with the forced circulation of Engineering Data Available filtered room air. The Year Around Air A Herman Nelson Sales Representative Conditioning Unit is to be specified for will be pleased to cooperate with you in areas where winter and/or summer air planning the application of Herman Nelson conditioning are required. equipment. To obtain this service or to Residential buildings also may be secure a reference file of Herman Nelson served with Herman Nelson equipment. Engineering Data, contact one of our sales For forced air heating, the Oil Burning Air representatives or the Home Office at Conditioning Furnace or the Gas Burning Moline, Illinois. Propeller-Fan Type hiJei Healer The New "Herman Nelson Air Conditioner for Schools 835 Oil Burning Air Conditioning Furnace Air Conditioning a^'c^'"s John J. Nesbitt, Inc. Holmesburg, Philadelphia, Pa. 11 Park Place, New York City 205 W. Wacker Drive, Chicago, 111. Manufacturers of ' THE NESBITT SYNCRETIZER Heating and Ventilating Unit, sold by John J. Nesbitt, Inc., and American Blower Corporation; NESBITT HEATING SURFACE with Dual Steam-distributing Tubes, NESBITT SERIES H HEATING SURFACE, and NESBITT SERIES W COOLING SURFACE, sold by leading manufacturers of fan-system apparatus; WEBSTER-NESBITT UNIT HEATERS (for details see page 957), distributed in the U.S.A. by Warren Webster & Company. . The Nesbitt Syncretizer--Series 400 The last word in heating and ventilating x units for schoolrooms, offices, etc., where the continuous introduction of outdoor air is desired. For engineering data, get Publi cation No. 225; for "The Story of Syncretized Air," Publication No. 231. Nesbitt Series B Thermovent For heating and ventilating auditoriums, gymnasiums, assembly halls, and similar gathering places. Publication No. 227. Nesbitt Series H Heating Surface ALL COPPER A lightweight, enduring, highly efficient blast-coil heating surface of tube-and-fin construction, made entirely of copper and copper alloy, designed for use with steam pressures up to 200 lb gauge. Large headers of seamless copper tubing with, collars extruded from the header body, providing large areas to which the condensing tubes are silver brazed. Seven types,each in eight fin widths and up to six teen finned lengths--a total of 784 sizes from which to select. Sold by leading manufacturers of fan-system apparatus Nesbitt Heating Surface with Dual Steam-distributing Tubes Copper tube-and-fin surface for low- pressure applications. Perfectly adapted to close, continuous automatic control with modulating steam valves. Steam-distri- ' buting tubes within the condensing tubes carry the steam equally to the full section, assuring UNIFORM discharge tempera tures, even under a throttled steam supply; eliminating temperature stratification; pre venting tube freezing without preheaters; giving ideal system results. Cased or uncased units of many sizes and capacities. Sold (like all other Nesbitt Surface) by leading manufacturers.of fan- system apparatus (list upon request). For full particulars and engineering data, send for Publication No. 229-1. ' Nesbitt Series W Cooling Surface ' For all air-cooling applications -using (list upon request). Send for Publication No. 232 for complete engineering data. chilled water. Continuous and cleanable tube types. Tube-and-fin construction. * For full particulars and engineering data, send for Publication No. 233. 836 Air Conditioning Unit Heaters and Coolers Refrigeration Economics Co., Inc. Canton, Ohio ' RECOY PRODUCTS RECOY AIR CONDITIONING UNITS of the suspended type as shown, or vertical floor type, are made for all season purposes, also for summer cooling or winter heating and humidifying. Capacities range from one ton up to anv size required. Cooling and heating surface, and filter area are liberally pro portioned and blowers are of moderate speed, all to insure the highest efficiency and quiet, satisfactory performance. Bulletin E . RECOY CONTINUOUS FIN BLAST COILS for cooling or heating are constructed of copper tubing with aluminum fins, or all steel hot dip galva nized after fabrica tion and are suitable for use with any cool ing or heating medi um. Bulletin "F". RECOY EVAPORATIVE CONDENSERS are cooling towers and condensers combined into one efficient unit for use indoors or out. They reduce the water consumption 95 per cent and are used with no water at all in cold weather. Made in sizes from one to one hundred tons. Bulletin "F". RECOY DOWN DRAFT FIN COILS are used for all refrigerating purposes for tem peratures above 34 F. Coils defrost at every cutout period and are equipped with alu minum troughs that catch the water. No coil bunkers or pans required. Air circulation unimpeded and very rapid and humidities of 85 to 90 per cent are easily maintained. Coils are made of aluminum, copper, or steel hot dipped galvanized after fabrication. They require only about 12 in. of head room and may be hung up to the ceiling between meat rails, etc., thus conserving space and reducing the cost of cold storage rooms. Bulletin "F". RECOY REFRIGERATING FINNED COILS and unit coolers are made up on con tinuous copper, or aluminum tubing (no joints so no leaks), with aluminum fins, or all steel, hot dipped galvanized after fabrication. Fins are corrugated to hold moisture in the air stream during off cycle to re-evaporate and maintain high humidities. They are applica ble to both large and small work. Bulletin "F". 837 Air Conditioning Unit Heatera and Coolers The Trane Company 2021 Cameron Avenue, La Crosse, Wisconsin MANUFACTURERS OF HEATING, COOLING AND AIR CONDITIONING EQUIPMENT Over 80 U-S. Branch Offices Allentown, Pa., Altoona. Pa.. Amarillo, Tex., Appleton, Wis.. Altanta. Ga.. Aurora, III., Baltimore. Md., Birmingham, Ala.. Boston. Mass.. Brooklyn, N. Y., Buffalo, N. Y., Canton. Ohio. Charleston, W. Va.; Chattanooga. Tenn., Chicago. 111., Cincinnati, Ohio, Clarksburg. W. Va., Clarksville, Tenn., Cleveland. Ohio. Columbus, Ohio, Dallas, Tex.. Davenport, la., Dayton. Ohio. Denver. Col., Des Moines, la., Detroit, Mich., Flint. Mich., Gainesville. Fla.. Grand Rapids, Mich-, Greensboro, N. C., Greenville, S. C-. Harris burg, Pa.. Houston. Tex., Indianapolis, Ind.. Jackson, Miss., Kalamazoo, Mich., Kansas City, Mo., Knoxville, Tenn., LaCrosse. Wis., Lake Charles. La.. Little Rock. Ark.. Livingston, Mont, Los Angeles* Calif., Louisville. Ky., Memphis. Tenn., Miami, Fla., Milwaukee, Wis., Missoula. Mont., New Orleans, La., Newark, N. J.. New York, N. Y,, Oklahoma City, Okla. Omaha, Neb.. Peoria, 111.. Philadelphia, Pa., Phoenix, Ariz.. Pittsburgh. Pa., Portland, Me., Portland. Ore., Portsmouth, Ohio, Providence, R. I., Richmond, Va., Roanoke. Va.. Rochester, N. Y,, Salt Lake City, Utah, San Antonio. Tex., San Francisco, Calif., Scotia, N. Y., Seattle, Wash., Sioux City, la.. South Bend, Ind., Spokane. Wash., St. Louis, Mo.. St. Paul, Minn., Syracuse. N. Y., Toledo. Ohio, Washington, D. C., West Hartford. Conn., West Haven. Conn.,. White Plains. N. Y., Wilkes-Barre, Pa., Zanesville, Ohio. Foreign Branch Offices Buenos Aires, Arg., Hong Kong, China, Manila, Phillipine Is., Melbourne, Australia, Mexico, D.F. Export Dept.: 75 West St., New York, N. Y. In Canada: Trane Company of Canada, Ltd., Mowat and King Sts., W., Toronto, Ont. (11 Branches) TRANE EDUCATIONAL MATERIALS Trane Air Conditioning Manual cycle and the solution to a problem sug- gests itself. In addition, this process is as simple as reading a standard yardstick, only one reads Btu's instead of inches. The ruler measures the difference between two wet-bulb lines giving a direct reading on the total heat to be removed, A switch to the Trane Chart-and-RuIer Method wiil save two-thirds of your time in figuring air conditioning problems. TRANE PRODUCTS Trane Convectors Trane offers the engineering profession a comprehensive, straightforward and un . biased textbook covering the fundamentals of air conditioning. Trane engineers have gathered all available material, sifted and analyzed it carefully to produce in one volume the essence of air conditioning practice. The Trane Air Conditioning Manual not only shows how to design every type of air conditioning system, but also clarifies underlying principles enabling both the student and the engineer to reason out their own problems rather than to blindly follow complicated formulas. Price --$5.00, Trane Air Conditioning Ruler and Psychrometric Chart To solve air conditioning problems with speed and accuracy, The Trane Company has developed the Air Conditioning Ruler and Psychrometric Chart. It eliminates the laborious calculation entailed by out moded methods. The chart and Ruler visualize the complete air conditioning In using the Trane Convector it costs no more for the smooth, steady flow of clean, even heat obtained. It costs no more for a lighter, yet sturdier, unit which hassuperi_or heat transfer abili. ty. You pay no bonus for the harmonious design of this clean, space saving method of heat diffusion for all steam and hot water heating sys tems. Trane offers a complete line for both visible and concealed installation. Trane Projection Unit Heaters With the Anemostat equipped Trane Pro jector you now, for the first time, can specify a unit heater which gives complete heat dif fusion with no noticeable air movement. This unit may be installed directly over desks and other busy areas. Wastes.no space. Effective heat diffusion for both high and low ceilings. No drafts, no hot soots, no cold soots. 838 The Trane Company Air Conditioning Unit Heaters and Coolers Trane also manufactures a huge line of standard projection, propeller, and blower unit heaters for every conceivable unit heating need in buildings of all types. Trane Air Conditioners There are three broad classes of Trane Air Conditioners (Climate Changers): (1) Commercial, (2) Industrial, (3) Domestic. All are durable blower units performing the complete summer phase and/or the com plete winter phase of air conditioning. All units may be furnished for either steam or hot water heating, and for cooling with water, brine, or direct expan sion refrigerant. With typical Trane thor oughness, the lines are made available in a wide range of sizes and styles, for floor, suspended, or concealed installation. Trane Self-Contained Air Conditioners Only simple condenser water and electric connections are necessary to place this com plete Air Conditioner in oper ation. It may be equipped with hot water or steam coils. Uses Trane Reciprocating Compressor, available in 3, 5, lx/2 and 10-ton .capacities. Handsome, sturdily built. Trane Refrigeration Units Trane Coils The integral finand-tube construc tion of the Trane Coil provides complete heat transfer for all heating, cooling, dry ing, and air condition ing services. Trane has several thousand different styles and types of coils to meet all requirements. Types include: high and The Trane Turbovac is a hermetically sealed, centrifugal type water chiller which operates under low pressure. It is a complete "equipment room" in one com pact package. Only two moving parts and 25 per cent lighter than reciprocating types. Trane also manufacturers a com plete line of' Reciprocating Compressors available in sizes from 3 to 50 tons capa city. Built for long term performance. low. pressure steam coils; hot and cold water coils; blast coils; drying coils; direct Trane Gas-Fired Equipment * expansion coils; coils of special materials for special gases or liquids; easy-to-clean coils for water containing foreign matter; coils for installation in units, in ductwork, or for separate service. Trane makes a complete line of coils. Trane manufacturers a complete line of gas-fired equipment, including Gas Space Heaters, Unit Heat ers, and Horizontal and Vertical Gas-Winter Air Conditioners. These units Trane Cooling Equipment embody a light-weight heat generator and heat ex Trane manufactures a changer--speedy heat complete line of Evapo maker--safe and automatic. rative Condensers, Evapo rative Coolers, Product Coolers, Brine Spray Other Trane Equipment Units, Comfort Coolers, Trane's line also includes Railroad and Bus Air complete Heating Specialty Conditioners, and Radio products -- Traps, Valves, Tube Coolers. The Trane Boiler Specialties and Vents. Evaporative Condenser Also, Condensation, Circulat (shown) saves up to 90 per cent in water ing and Booster Pumps, Tem costs for refrigerant condensing. Trane perature Control Valves, Air Washers, Cooling Equipment is available in the Spray Nozzles, Fans, Unit Ventilators, correct size or type to meet any require Humidifying Conditioners and Dehumidi- ment. | fiers. Write for Bulletins 290 and S400. 839 Air Conditioning Unit Heaters and Coolers The Unit Heater and Cooler Co. Wausau, Wisconsin , Offices In Principal Cities MANUFACTURERS OF THE GRID UNIT (patented) All-cast aluminum "fins" bonded to cast high-test iron core. No soldered, brazed, or expand ed joints -- no unions--no seams --fewest,, connec- lions possible. Typical Installation of Grid Unit Heater GRID UNIT HEATER DATA Model No. Dimensions . Inches' A B c D* Face . Area Sq Ft Motor Hp Rpm Vol. Capacities 5 Lb Steam 60 Air Approx. Shipping Pipe Sites Fan Btu Final Temp. Weight Supply Return 1000 16% ii% "9% (6 0.84 1200 IS'/z 13% 11% 17% 1.04 515 23% 17% 11% 20 1.65 * 1500 ay, 17% 11% 20 1 67 1520 27% 17% 11% 20 2.2 520 28% 22% 11% 21% 2.9 - 2000 28% 22% 11% 21% 2.9 - 2025 33% 22% 11% 21% 3.6 : 525 33% 27% 13 28 4.5 . * 2504. 35% 27% 13 2d 4.5 2500 35% 27% 13 28 4.5 2530 37% 27% 13 28. 5.3 530 39% 32% 13 29 6.5 3000 39'/ 32% 13 29 6.5 3000 39'/ 32% 13 29 l 6.5 1/20 1/20 1/10 1/10 1/10 1/6 1/6 1/6 1/2 i/ 1/2 1/2 1/2 1/2 1% 1700 1700 1750 1750 1750 1150 1150 (150 1150 1150 1150 1150 1150 850 1150 578 71 f 1290 1450 1700 2500 2500 2875 4200 3200 4200 4650 5300 6350 8100 29.400 107 46.000 119 59,600 102 77,500 109 104.000 _ H3 102,300 97 148.000 114 177,000 115 166.400 94 210.000 118 225.000 108 282.000 115 260.500 105 341,000 109 394.000 104 100 i%" i%" (20 i%" i%" 160 i%" i%" 210 i%" i%" 250 i%" i%" 250 2" i%" 32? 2" i%" 370 2" - i%" 390 420, 2" 2" i%" i%" 440 2" t%" 530 2" i%" 600 . 2%" i%" 690 2%" i%" 725 2%" i%" .'Varies with type of motor. GRID UNIT HEATERS ARE NOT AFFECTED BY ELECTROLYTIC ACTION No leaks--no breakdowns. Low maintenance expense. More air changes per hour. Positive "directed" heat. Lower outlet temperatures. Larger air volume. Reduced fuel cost. Applicable to either low or high steam pressure lines. Send for Bulletin on Units not listed above. 840 Air Conditioning Unit Heaters and Coolers YUNG RADIATOR Kjompjmiu Offices in all Principuall CriitIiees * # Racine, Wis. Write For Literature Engineering Information At Request Air Conditioning Unit Air Conditioning Units--are made in five physical sizes for home and industrial installations. Designed to do a complete air-conditioning job, heating, cooling, hu midifying, and dehumidifying. ilodd SH Unit Heater Unit Heaters--Model SH and TH. A complete.line of single and twin fan suspended units, 32 sizes ranging in capacities from 18,000 to 658,000 Btu per hr. Mfrlel FH Unit Heater "FH" Unit Heaters--ten models rang ing in capacities from 120,000 to 800,000 Btu per hr. These units are equipped with two, three, and four blower type fans, driven by single or variable speed motors. Type ' Cooling Coil . . STREAMAIRE Convectors--areavailable in six distinct types of cabinet enclossures--free standing,! wall hung, partially recessed, fully recessed, bathroom cabinets, and plastered-in enclosures. Designed to operate on one pipe steam, two pipe steam, vapor, vacuum and. gravity hot water heating systems. Cooling Coils--Type tinuous tubes, type "K" "W" with rwemithovcaobnle-..TCCy..pooooell"iin;Kg " headers for use with water or brine. C" oil Commercial Units Commercial Units--Designed for use in connection with .Heating, cooling, and air-conditioning units where a compact, efficient, heating surface is desired. Blast Units---as encased heating sur face for use in connection with forced air, heating, and cooling systems. . Blast Units "FC" Heating Units--combine the appearance of a STREAMAIRE convector with the higher capacity of YOUNG Unit Heaters. Available in four physical sizes, equipped with single and two speed motors. Type FC Healing Units Evaporators--Designed for mechanical refrigeration systems using Freon or methyl chloride. 841 Evaporators -- - ..... v w;r International Heating & Ventilating Exposition THE AIR CONDITIONING EXPOSITION Permanent Address--Grand Central Palace, New York, N. Y. EXPOSITIONS HELD The first in Philadelphia, 1930. The second in Cleveland, 1932. The third in New York, 1934. The fourth in Chicago, 1936. The fifth in New York, 1938. The sixth in Cleveland, 1940. , Subsequent Expositions will be held on alternate, even numbered years. These are -held coincident with the Annual Meeting of the American Society of Heating and Ventilating Engineers and are directed by the International Exposition Company, under the auspices of the A.S.H.V.E. EXHIBITORS Comprise leading firms in each phase of the industry: number has varied from 150 to 327 exhibitors. EXHIBITS These range from and comprise all the types of articles discussed or advertised in this copy of The A.S.H.V.E. Guide. 1. The Combustion Group: Furnaces, burners (coal, oil and gas), grates, stokers, boilers, radiators (vari ous types), refractories and auxiliaries. 2. The Oil Burner Group. 3. The Hydraulic Group: . . .. Water feeders, water heaters, pumps, Straps, valves, piping, fittings, expan sion joints, pipe hangers, etc. 4. The Steam Heating Group: Vapor heating and steam specialties. 5. The Hot Water Heating Group. 6. The Air Group: Warm Air furnaces and stoves, regis ters and grilles, cooling towers, air filters, motors, fans, blowers, condi ... tioning. equipment, ventilators (room - and industrial types), unit heaters, etc. 7. The Air Conditioning Group: Equipment which circulates and filters the air, in summer dehumidifies and cools; in winter heats and humidifies, and does all these in proper season for S complete,-, all .year round air condi- l ' tioning. if7 !8. The Controi"Group: Instruments of precision for indicating, controlling or'; recording temperature, pressure, volume, time, flow, draft or any other function to be measured. 9. The Refrigerating Group: . Compressors, <c6ndensers, cooling ap paratus, contingent apparatus and refrigerants. 10. The Central Heating Group: Apparatus and materials especially designed or adapted to the uses of central heating and central heating station supplies. . 11. The Insulating Group: Structural insulators (refractory and cellulose materials), asbestos, mag nesia clays and combinations thereof, pipe and conduit covering, etc., weather-stripping, etc. 12. The Miscellaneous Group: Electric Heaters, boiler and pipe re pair alloys, liquids and compounds, tools of all kinds, and equipment not specifically included- in the above groups, but related thereto. 13. The Machinery and General Equipment Group. 14. Books and Publications. VISITOR ATTENDANCE Comprises a registered attendance in vited to the exposition and includes: (Figures are 1938 analysis) Industries i ; Governmental........:............................ 872 Distribution. Channels Contractors. Dealers, Jobbers. Supply Houses, 32 classifications.............................. _18,483 Home Owners........ ......... .......................... -........... 299 Industrial Users. 95 classifications.--...............10,504 Professional and Service Organizations, ' 43 classifications........ ..................... ..--.......... - 3.365 . Public Utilities............................... ;-- 2,124 Real Estate Management and Operation, 18 classifications.___________ 2,683 Educational Institutions...... ........................ --.-- 921 Miscellaneous..... ...... 806 Total........ ....................... 40,057 Occupations Executive (22 titles).......................................-..... 19.718 Construction (24 titles and trades)--............... 7,877 Operation (21 titles and trades)........................ 3,975 Technical (122 titles)........ .................... --......... 6,015 Not Classified including Educators. Pub lishers, Home Owners, etc..:......................... 2,472 Total..--. .40,057 Industrial Expositions in America lead the expositions of the world in style, business effectiveness, industrial influence and educational value. This Exposition stands among the- leaders in Industrial Expositions, in America. It is an edu cational institution which biennially brings together the research developments and improvements in equipment and materials for use in heating, ventilating and .air conditioning all types of buildings. 842 AIR SYSTEM EQUIPMENT Air systems for heating, cooling and ventilating services are produced by grouping various machines and accessories, each performing a function in the complete cycle of the desired operation. The essential parts and acces sories described by the manufacturers are contained in the following groups: AIR FILTERS AND CLEANERS (p. 844-856) Mechanical and electrical methods of filtering, also air washing and purifying apparatus and their applications. .. Technical data on this subject will be found in Chapter 27. HUMIDIFYING UNITS (p. 857-876) For supplying moisture to air and controlling its volume as desired for industrial and commercial uses, or for comfort requirements. Technical data is contained in Chapter 24.. COOLING TOWERS AND SPRAY EQUIPMENT (p. 858-861) For cooling and reclaiming water used in industrial processes and air conditioning. Technical data will be found in Chapter 26. * HEAT TRANSFER SURFACES (p. 862-865) - As parts of heating and cooling units, and for separate use in industrial and commercial heating and cooling systems. Technical data is contained in Chapter 25. CONDENSING UNITS AND REFRIGERATING MACHINERY (p. 866-876) For refrigerating processes and for cooling purposes in industrial, commercial and comfort, air conditioning service. . Technical data will be found in Chapter 24. FANS AND BLOWERS (p. 877-891) For use as separate air circulating equipment, or as parts of heating and air con ditioning units. Technical data is contained in Chapters 23 and 28. MOTORS <p. 892-894) . Used in conjunction with blowers, fans, stokers, oil burners and other heating, cooling and air conditioning apparatus. ' Technical data on motors will be found in Chapter 39. REGISTERS AND GRILLES (p. 895-906) Air diffusion equipment for use with heating, ventilating and air conditioning, systems. Technical data relating to this equipment is contained in Chapters 29 and 30. SHEET METAL AND TUBULAR PRODUCTS <p. 907-910) Sheets for air ducts and enclosures; pipes for gas, refrigerants, steam, water, etc. Technical data on pipe and piping is contained in Chapters 16, 18, 34. ..Manufacturer's products shown in this division are designed for specific applications. Consult the Index to Modern Equipment for additional products of these manufacturers. 843 Air System Equipment Air Filters end Cleaners The Air-Maze Corporation 5202 Harvard Avenue, Cleveland, Ohio ENGINEERS AND MANUFACTURERS OF AIR FILTERS EXCLUSIVELY Direct Factorv Representatives in All Industrial Areas. Distributors in principal cities and towns throughout the United States. During more than a decade devoted exclusively to air filter engineering and manufacturing, a great deal about the control and elimination of dust, pollens and grit has been learned by AIR-MAZE engineers. Their design and development of a unique type of filter element con struction, embodying distinctive advan tages, has been considered a worthy con tribution to the air filtering science and has resulted in wide acceptance of AIR-MAZE air filters in all fields of application. Efficiency--Tests under varying con ditions, both in laboratoriesand-field oper ations, show air filtering efficiency of from 98.00 to 99.83 per cent with practical dust. No Clogging -- Because AIR-MAZE panel filters are easy to completely clean and since the exact density enables uni form deposit of dust, no clogging can occur. Adaptibility--In addition to air condi tioning and power equipment installations AIR-MAZE panel filters are effectively used in humidifiers, water eliminator units, paint spray-booths, oil separators, range canopies in kitchens, and other applica tions where specific problems and unusual requirements are easily handled by adapta tions of the panels. AIR-MAZE panels will be made to fit frames of existing installations and can be furnished with locking handles and latches, snap catches, or with flanged edges and lift handles. 4 in. Thick Panel in. Thick Panel Views showing open end edge of AIR-MAZE Permanent Clcanable Panel Fillers Note Advantages Made Possible by Air-Maze Scientific Construction: Costs Little to Clean--The separating layers and exact spacing of baffles permit free washing action between and around all baffles. Thus, cleaning and charging operations may be easily and economically performed. Great Dust Capacity--Unique design of the AIR-MAZE screen wire element provides a vast area of baffles on which collected material can become impinged; thus great capacity is assured. Magnified Section of "Loaded" AIR-MAZE Air Filter Element. Nqte that dust has been quite evenly impinged on the wires. No obstructed spaces can be seen. This feature accounts for the Low Pressure Drop and Non-clogging characteristics ofAIR-MAZE TECHNICAL INFORMATION Vibration Proof--Vibrations in service cannot shake filter media out of position-- the uniform density remains permanently perfect; no replacements are necessary! AIR-MAZE Are Listed by Under writers' Laboratories--When serviced according to the methods recommended by the Underwriters' Laboratories, AIRMAZE panel filters are approved as fire retardant air filters. Sizes--All sizes and thicknesses are available; two and four inch thick panels are the accepted standard. Installations using large sizes of these permanent panels are surprisingly low in cost. Capacity--Recommended air capacity is 1}4 to 2Yi cfm per square inch. Thus, the capacity of a' 20 x 20 in. panel is 600 to 1000 cfm. Normally, 2 cfm per square inch should be used. 844 Air System Equipment Air Filters and Cleaners The Air-Maze Corporation * 5202 Harvard Avenue, Cleveland. Ohio * Resistance--For 2 in. thick panels the resistance varies from 0.089 in. to 0.10 in. HiO when handling 2 cfm per square inch of filter area (288 fpm velocity); and for 4 in. thick filters the resistance varies from 0.121 in. to 0.140 in. H*0 at 2 cfm per square inch (288 fpm velocity); the vari ation being in accordance with the differ ent types of filter media construction available. To obtain specific restriction data write for graph RE-2A. Construction--AIR-MAZE filters are of patented construction consisting of a maze of alternately placed and exactly spaced crimped galvanized wire screens of selected meshes; these are arranged with precision so as to create graduated and progressive density, and to positively em body the baffle impingement principle. The filter element is enclosed in a heavy gauge metalescent enameled steel frame having an open end to simplify servicing. EASY TO CLEAN AND CHARGE Cut-away View drainage. After cleaning and also after charg ing, set Panel on edge, with open end down, to drain. Cleaning--Simply tap panel a few times on a hard surface to remove heavy accumulations and then wash under a stream of hot water or in a pan of hot water. Steam also cleans the panels quickly and effectively. Be sure filter is dry before charging. Charging--(For general applications) Spray both front and back of panel with just enough oil to coat the wires. Any inexpensive oil of S.A.E. 30 viscosity is suitable. An ordinary insect spray gun will do the work splendidly. Or, if desired, panel may be immersed in oil and then thoroughly drained. AIR-MAZE INSTALLATION FRAMES frames assure efficient, attractive installations. AIR-MAZE panel holding frames are constructed of metalescent enameled heavy gage steel having % inch flanged back edge. A thick felt lining on inside of flange insures against air leakage when panels are in place. One frame may be used alone in single panel installations, or a group of frames may be supplied, fixed together; thus a large bank of filter panels may be provided. Every frame section is fitted with snap catches as standard equip ment; a lift handle is installed on each panel. In determining frame sizes, ^6 inch is allowed over the EXACT width, and % inch over the EXACT height dimen sions of the panels. These dimensions include frame edge, clearance and felt edge seals Specify AIR-MAZE--for all air filter installations and you will be assured of efficient, economical performance. Write for specification bulletin CCC-69. Engineering Service Available--The Air-Maze Engineering Department will gladly offer installation suggestions for special air filter applications. Other AIR-MAZE Products--In ad dition to the panel types, Air-Maze Cor poration also manufactures a complete line of circular shaped air filters for use in various Railroad, Industrial and Auto motive applications. Literature Available -- Catalog de scribing industrial types "A", "B" and Greastop panel filters. Catalog describing Kleenflo panel filters. Catalog describing Air-Maze Oil Bath type, Multimaze and Unimaze filters for internal combustion engine, air compressor and blower appli cations. 845 Air System Equipment Air Filters and Cleaners American AirJilterCompany Inc. 1st Street and Central Avenue, Louisville, Ky. Representatives In Principal Cities Dust Engineering--Dust Engineering is that branch of applied science which deals with the origin, nature`and characteristics of the small solid air-borne particles called "dust," and the development of methods, processes and apparatus for its control or elimination. The American Air Filter Company, Inc., has had an important part in advancing the science of Dust Engineer ing. The efforts of its Re search and Engineering Staff for the past twelve years have been devoted exclusively to the study of dust problems and the development of a complete line of air cleaning equipment for modem air conditioning, building venti lation and the control of pro cess dust in industry. American Air Filter pro ducts, therefore, not only embody the knowledge ac cumulated from years of con stant research and the ex perience gained from design ing, building and applying thousands of air filters, but are backed by ample technical and financial resources to in sure their outstanding posi tion in the Dust Engineering field. Products--American Air Filters are available for every condition, with operating characteristics and efficiencies to suit specific problems. In general, there are two distinct types based upon the "viscous Renu-Vent Filter used for the removal of dust, dirt, bacteria and other foreign matter from the air and are applied to general ventilation, modem air con ditioning, process dust con trol; for air compressors'and Diesel Engines; mill motors, turbo-generators and other electrical applications; and for air or gas under pressure to remove entrained oil, moisture and dirt. Airmo.1 Type PL-24 Filter Air Filters In Air Con ditioning--Filtered air is today recognized as essential in modem air conditioning. There are other important factors which contribute to our comfort such as tem perature, air movement and humidity, but science today emphasizes the prime neces sity of pure air for health and efficiency. Air cleaners have, of course, always been considered an integral part of large central systems. These are usually of the fully automatic type such as the Multi-Panel filter, illustrated in the accompany ing.photograph. There are now available to manufacturers of unit air conditioners moderate priced unit filters such as the Renq filter, the Throway filter, and other types of filters illu strated on this page. The Renu filter is an Throway Air Filter entirely new departure in air filter construction. It con film" and "dry mat" principles. Each type is made in several styles which differ in method of sists of a permanent metal frame provided with a re movable cover and renew able filter pad. The cover operation, servicing, space required and initial cost to meet the various con ditions encountered in air cleaning problems. A dis cussion of various filter types will be found in the Technical Data Section under "Air Cleaners." Air filters are generally Standard Viscous Unit Filter 846 American Air Filter Co., Inc. Air System Equipment and Cleaners is easily removed without (he use of tools, and niter pad can be lifted out and replaced with a new one at very small expense. The Throway filter, as the name implies, is de signed to be discarded after it has served its maximum period of usefulness and re placed with a new filter unit. The Filter pad is enclosed in a perforated cardboard con tainer which makes it pos sible to readily dispose of the dirty filter by burning it. There is probably no sin gle item which costs as little and may mean as much in the design of an air con ditioner as air filtration. These units are furnished in any dimensions or shapes desired--usually in units handling 400 cfm and from 2 in. to 4 in. thick. They are usually made in the following sizes--20 x 20 in., 16 x 25 in. and 16 x 20 in. High cleaning efficiencies can be secured, with a re sistance to air flow ranging from Hfi in- to M in- water gauge. Automatic Self-Clean ing Air Filters--The American line of automatic air filters is among the most complete ever offered. Prov ed in principle and perform ance by years of actual service. Electro-Matic Air Filter--Incorporates elec trical precipitation as an integral function of an auto matic self-cleaning viscous filter to obtain a higher over-all efficiency in dust removal. Its higher effi ciency as an air cleaning unit, is due principally to the collection of the finer dust particles and smoke, by electrical precipitation. In combination,, th^e two methods of cleaning air not only give the highest effi ciency in dust removal but offer operating advantages found only in the automatic self-cleaning filter.' Armored Multi-Panel Automatic Armored Multi-Panel Filter--Introduces an en tirely new and unique panel construction to further im prove the already outstand ing performance of the famous Multi-panel air filter. The new "armored" panel with its three stages of air cleaning maintains the present high efficiency and normal operating and resis tance of the Multi-panel filter and offers the added advantage of handling ex cessive lint concentrations or heavy dust loads without clogging. Standard Viscous Unit --The American Unit Air. Filter incorporates the time tested unit principle of con struction. Each unit con sists of a standard steel frame and interchangeable cell equipped with auto matic latches to facilitate removal for cleaning and recharging. , Section of Multi-Panel filter curtain showing unique construction of new Armored Panel. Dark portion of screen is bakelite-fibre coated. The bright uncoated screen lies immedi ately behind the Armored section of the preceeding panel and provides the second or intermediate stage of air cleaning. The Armored section is at the bottom of the panel. -Airmat Filter Dry Type --The filtering media in this type is. the Airmat sheet, a dry filterjniat composed of thin sheets of gauzy, cellu lose tissue. The Airmat sheets :are;: supported in screen pockets mounted in a unit framedf box-like con struction. Tnese unit frames can be set up to meet any capacity requirement or space conditipn. Airmat sheets are renewable--their life depending bn dust con ditions and hours of service. Airmat filters are used both for comfort and indus trial air conditioning. In the latterfield they are particu larly well adapted for the recovery of valuable dusts and for abating the dust nui- r sancq prevalent in so many industrial plants. They are available in two types, the PL-24 as illustrated and the Well. Pocket type unit. Electro-Matic Air Filter 847 Our standard data books arid Catalogues are in most engineering files or libraries. ' We wiirbe'glad to furnish complete data to engineers or manufacturers. Air System Equipment Air Filters and Cleaners Coppus Engineering Corporation 339 Park Avenue, Worcester Mass. MANUFACTURERS OF AIR FILTERS, STEAM TURBINES, GAS BURNERS, FORCED DRAFT BLOWERS, COOLING FANS. "COPPUS AIR FILTERS PASS CLEAN AIR" The Coppus Unit Air Filter (patent No. 2050508 and other patents pending) is of the dry type using as filter material all wool felt. It consists of a distender frame (C, Fie. 2), a filter "glove" (E, Figs. 1 and 2) ana a retainer grid (B, Fig. 1). The edges of the retainer grid form a reenforced sheet metal box {A, Fig. 1) for protection of the filter element. The edges of the filter glove are reen forced on all four sides assuring an air tight seal against by-passing of dirty air. By tightening the wing studs which hold the distender frame and the retainer grid together, the filter glove is stretched and held tautly inside oi the filter box, giving the pockets a tapered shape so essential for an even air flow. This design has the advantage of pro viding an effective filter area entirely unobstructed by wire or screen supports. Cut, Fig. 3 shows the tapered filter pockets on the clean air side. The filter glove can be readily replaced without removing the unit filter from the installation. No aux iliary frames for insertion of the filter cells are required as the completely assembled unit filters can be bolted together to a filter bank of any desired size. All metallic parts are rust-proofed and Duco Painted. . Fig. / . Fig. 8 Specifications Normal Rating: 800 cfm. Resistance when clean: -0:24n._W.G. Dust Arrestance (cleaning efficiency): 99.61 per cent (Tested in accordance with A.S.H.V.E. Standard Code for Testing and Rating Air Cleaning Devices Used in General Ventilation Work). Dimensions: 20 by 20 in. by 5% in. Weight per unit: ; 25 lb. Fig. 3 ANOTHER COPPUS BLUE RIBBON PRODUCT Outstanding Advantages . 1. It has an exceptionally high dust arrestance. 2. It maintains a high dust arrestance even under diverse conditions of neglect. 3. Its operation is not impaired by atmospheric conditions. 4. It is a Medium Air Resistance Type (Class C) according to the A.S.H.V.E. Code for Air Cleaning Devices. 5. It is easily and quickly cleaned without removing the filter element. 6. Its cost of upkeep is very low because the permanent filter element is reconditioned periodically with a vacuum cleaner. 7. It combines scientific knowledge and practical engineering methods with highest quality oi material and workmanship. Write for Complete Bulletins ' 848 Cleaning Filter Elements with Portable Vacuum Cleaner Air System Equipment Air Filters and Cleaners Davies Air Filter Corp. - 396 Fourth Avenue, New York, N. Y. Air Conditioning, Process, Building, Industrial Filters AIRPLEX RENEWABLE FILTER Airplex filter medium is cotton fibre, specially processed and lightly glazed. Each filter contains 30 sq ft of filter medium and gives 500 to 1000 hours active service. Functions efficiently in temperatures below freezing and up to 200 F. Not affected by temperature or humidity--will not dis integrate. Filters can be cleaned several times before they are discarded. Each filter is a complete cartridge-- replacement can be made quickly, hence is not neglected. Standard Sizes Airplex Filter (20 x 20 x 4 in. Process. Industrial, Building.... -- <25x 20x4 in. (24 x 24 x 4 in. Home Air Conditioning 520 x 20 x 2 in. Units................................................. (25 x 16 x 2 in. PERMAT WASHABLE FILTER Filter medium of fine spun hair glass closely packed and secured between two sheets of galvanized wire cloth;these long flexible glass fibres do not break and cannot be drawn into the air stream. Filter element supported in a steel frame, rust proofed or galvanized as required. Glass wool, being chemically inert,' is not attacked by gases or liquids, will not rust or disintegrate, will last many years. Water, hot or cold, with or without grease solvents, used for cleaning, depending on type of air pollution. Standard Sizes--Permat Filter Frame Size i Filtering ` Surface Capacity cfm Resistance 20 x 20 x 2 in. 25 x 16 x 2 in. 800 800 800 800 Other sizes arc available on request. .r w.c. .rw.c. "FILTERAIRE" For installation in windows--any type of construction. Provides con trolled ventilation, pure clean air, and eliminates disturbing noises. Attractive appearance--harmonizes with building finish and furniture. Model R capacity--500 cu ft of filtered air per minute. Model S capacity 300 cfm. Standard colors ivory and brown. Other colors are available. 849 Air System Equipment Air Filters and Cleaners Owens-Corning Fiberglas Corporation Toledo, Ohio All UTT 'TCDC FOR APPLICATION TO RESIDENTIAL, COMMERCIAL and tNDUSA1K rlLi cKS trial HEATING . VENTILATING and AIR-CONDITIONING SYSTEMS FIBERGLAS AIR FILTERS Trademark Reg. U- S. Pat. Off. "FIBERGLAS" MEDIUM - ADHESIVE-COATED - REPLACEMENT TYPE . The Fiberglas Dust-Stop Air Filter consists of a series of non-combustible Fiberglas, mats progressively packed-- coarse glass fibers of lesser density at the intake and fine glass fibers of greater Manufacturers* Acceptance Dust-Stop Air Filters are widely ac cepted by manufacturers of air condition ing equipment. density at the discharge face--between stamped metal grilles bound with a fiber- Standard Sizes for-Equipment* board frame. Mats are coated with non-evaporating, fireproof adhesive having extraordinary wetting .power, will retain viscosity under operating temperatures ranging from 15 F below to 300 F above zero, will not flow or charge the air with adhesive. Standard Sizes (Nominal) 2 25(r x " x r 20 20' X * * r 16" x 25" x l" 16" x 20" x 1" Ratings Cfm Fpm 1000 300 800 300 800 300 640 300 Resistance Inches Water Gauge Clean 0.045-0.050 0.045-0.050 0.045-0.050 0.045-0.050 Fiberglas Dust-Stop Air Filters are engineered to provide high efficiency at low cost of installation and maintenance. Efficiency--97 per cent (Tested accord ing to A.S.H.&V.E. Standard Code for Testing and Rating Air Cleaning Devices 20 20 220" x 25" x 2" "x "x " 16" x 25" x 2" 16" x 20" x 2" 1000 800 800 640 300 300 300 300 0.095-0.10 0.095-0.10 0.095-0.10 0.095-0.10 >'kY Other standard and any special sizes available. Used in General Ventilation Work). Engineering Service--Owens-Corning Fiberglas Dust-Stop Filters are made Fiberglas Corporation maintains offices in in two standard types: No. 1(1 in. thick) is several metropolitan centers where repre designed for greatest operating economy in sentatives, qualified to assist in the plan commercial and industrial applications. ning of filter' installations, are available No. 2 (2 in. thick) is designed for appli for consultation. " . cations where their greater dust holding capacity permits longer intervals between replacements. Both may be used in domestic applications. Literature--^ Datasheets on all standard Fiberglas products and applications will be furnished to engineers and -manu facturers on request. . 850 ;Air System Equipment Owens-Coming Fiberglas Corporation . Toledo, Ohio FOR HEATING, VENTILATING and AIR FiLTER FRAMES AIR CONDITIONING SYSTEMS fiberglas I FILTER FRAMES Trademark Reg. U. S. Pat. Off, Fiberglas Dust-Stop "L" and "V" Filter Frame Assemblies are installed by engineers of commercial and industrial heating, ventilating and air conditioning. Frame members of heavy steel are as sembled vertically in combinations to satisfy any CFM and space requirement. Both types of frames are designed for the convenient and correct handling of Dust-Stop filters. They meet all Fire Underwriters' and local Fire Ordinance requirements, as well as the requirements of Federal Specifications for filter frames. The choice between the "L" type and "V" type frames is determined wholly by the space available for the filter frames.. The "L" type filter frame takes less depth within the duct or plenum chamber but requires a larger face area for the same CFM capacity. The "V" type frame requires a face area approximately the same as the cross-sectional area of a duct which will handle the volume of air for which the filters are rated. Two Depths of "L" Frames--The "L" frame, two filters deep, is designed to hold two Dust-Stop No. 1 filters in each cell. The "L" frame, four filters deep, holds four Dust-Stop No. 1 filters in each cell. The frame that is four filters deep is identical in every way to the frame two filters deep except that the depth of all parts is 2 in. more. When specifying "L" type frames indicate two-filter or four- filter depth. . The "L" frame uses 20 x 20 in. filters only. The "V" frame uses 20 x 25 in. filters only. Filters are always used two or more in series in each cell. LEGND "L" Shaped Pa"* Membe 12 Left Hand Up*ght 20" f-3-X Beu, 20* F-3 Bate 20* *1 Betfmg Me*>be Double PUnge S-2 Retslne^ Meinbe' &ngle Pl9e R-3 Retaining Me-'be* Notched Angle O-l GeAct 851 LEFT--Dust-Slop "L" Type Filler Frame. ABOVE--Dust-Stop "V" Type Filter Frame Air System Equipment Air Filters and Cleaners Staynew Filter Corporation Air Filters for Every Purpose 6 Leighton Ave. Rochester, N. Y. PROTECTOMOTOR DRY TYPE FILTERS (For removing foreign matter from the air at atmospheric or other pressures, with various types for building ventilation, dust recovery, oxygen chamber and all air cleaning purposes.) The fin or V-type construction is used in all Pro- tectomotor dry filters. This basic principle permits (1) a large area of filtering medium to occupy the smallest possible space, and (2) the intake currents to move parallel to the filtering surface at low velocity. Protectomotor Dry Filters require no adhesive material to catch dust--odorless air is assured. Cross Section Showing Panel Unit Construction Authorities agree that the positive dry filter is most efficient in stopping the smaller air-borne particles. Protectomotor dry filters actually prevent the passage of bacteria. Cross Section of S Multi-V. Type Ceils in V formation EASY TO CLEAN --LONG LASTING Cleaning is easily effected by use of any to a year without cleaning. Panel units vacuum cleaner with special nozzle. average slightly longer wear than Multi- See illustration below. V-Type units--several years at least with- Protectomotors operate from 3 months out replacement. Panel Units: Consist of Panel Insert and Frame. The I nsert is composed of two rows of 60 hollow loops or fins 6 in. deep, formed of rust-resisting embossed wire mesh, supported by a retaining grate of steel or aluminum and similar spacing grate. Each row of fins is covered with a single piece of Feltex Filtering Medium, a felt-like material specially made for the application. Specifications below: Overall Dimensions (Depth less lock ing keys).............................1........... i........20 x 20 x 6% in. Size of Insert........................................... 19)-6 x 19M x 6 in capacity (average conditions)................................800 cfm Area of Filtering Medium........................................ 42 sq ft Linear velocity of air.................................................... 19 fpm Resistance of clean filter to air flow 0.185 in. water gauge. Total Weight.,..................................................................... 28 lb Outlet Side Panel Unit. Cleaning Noz zle in Circle. Multl-V-Type Units: Filtering medium (closely pressed cotton fibres between two sheets of cotton gauze) is arranged in patented V-shaped pockets in a fibre-board and pressed metal frame. These patented cells can be quickly and inexpensively replaced when worn out. Their arrangement makes possible an active filtering surface of 27 times face area. In certain installations the Multi-V-Type is more desirable than the Panel Unit because its construction fits the space better, or because it is lighter in weight per square foot of filtering area, or for reasons of economy. (Protectovent Window Ventilator, 'which supplies clean, fresh air to home or office, 1-fuIii- V-Type employs Multi-V-Type inserts). Complete speci- EascofCleani", fixations mailed promptly on request. 852 Air System Equipment Air Filters and Cleaners , Staynew Filter Corporation _ Air Filters for Every Purpose 6 Leighton Ave. _______ Rochester, N. Y. Wire-Klad Filler Sizes 20 in. x 20 in. 16 in. x 2S in. 16 in. x 20 in. 20 in. x 25 in. Wire-Klad Units: Unique method of construction permits a high efficiency filter a^- low cost. Fins are reinforced on both sides with screen cloth, producing a rigid, long-wearing, flame-resist ing filter that may be repeatedly cleaned with vacuum or com* pressed air, or flushed with water or liquid solvents. Made in 2 in. and 4 in. deep units. Specifications 7 in. and 4 In. Units Capacity -Wool Felt Capacity-- <0. 6460 Cotton 800 cfm. ( } 0.13 in. wg 800 cfm. <<l 0.12 in. wg 600 cfm. ( ) 0.11 in. wg 1000 cfm. C ) 0.12 in. wg 800 cfm. 0.08 in. wg 800 cfm. a 0.075 in. wg 600 cfm. @ 0.07 in. wg 1000 cfm. @ 0.08 in. wg Filtering Area sq ft 2 in. 16.5 2 in. 18.5 2 in. 14.8 2 in. 23.0 4 in. 38.5 4 in. 38.5 4 in. 30.7 4 in. 48.0 PROTECTOMOTOR AUTOMATIC FILTER (For efficiently and economicallyfiltering large volumes'of air for all ventilating purposes) This latest model Staynew Automatic Filter operates on the principle of dust impinge ment. Dust is caught by moving fitter panels moistened with oil from a reservoir. The panels are automatically timed to operate at pre-determined intervals (approximately 20 seconds each half hour; panel moves each time), de pending on the amount of dust to be removed and the air velocity. The filter possesses a number of unusual features which increase efficiency in dust removal and reduce oper ating costs. Several of these features are fundamental in design and found in no other filter. The result is a rugged, high-efficiency unit with which extremely large volumes of air can be filtered at low cost. Two Series of Panels There are two series of end less moving filter panels. Each series provides two stages of filtration -- four stages in all. The double series of moving filter panels is exclusive with Staynew. Efficiency is two fold. Counter-clockwise Panel Travel The panels travel in a counter-clockwise direction. This is an important, select feature. It means that the outlet side of each series of moving panels is the clean side always. The mechanism is ac tuated by a % hp motor with a reliable timing device (Telechron). Sizes and Capacities Two standard widths are made, 2 ft 9 in. and 4 ft 3 in., ranging in height from 4 ft to 13 ft by 3 in. steps. Capacities are from 2,025 cfm to 20,200 cfm for single units. Almost unlimited capacities may be secured by bolting together units. Automatic Fitter CtMOVAlU JO* COVfl -- Write for Catalog Mentioning Special Interests Diagram of Automatic. Filter PROTECTOMOTORS ALSO MADE FOR INTERNAL COMBUSTION ENGINES, COMPRESSORS, TURBO-GENERATORS, AIR TRANSMISSION LINES, ETC. 853 ; Air System Equipment Air Filters and Cleaners H. J. Somers, Incorporated Factory and General Office 6063 Wabash Avenue Detroit, Mich. Somers Washable Air Filter . Somers Hair Glass Filters provide everything required in an efficient air^cleaning system. Consider these features: High rating for dust, soot and bacteria separation. Require no adhesive, coating or impregnation. Indestructible in normal service. Minimum Low Pressure Drop. Odorless and non-absorptive. Fireproof; Washable; Do not rot nor disintegrate; Permanent. Somers Hair Glass Filters consist of a hot galvanized frame holding galvanized wire cloth packed with hair-spun glass strands. ' The glass strands are flexible, do not break up and cannot be drawn into air stream. Hair-Glass, being chemically inert, has no facility of absorption; it cannot rust and lasts indefinitely in service. Water either hot or cold may be used to clean it, without impairing its efficiency, These filters eliminate the necessity, the expense and the inconvenience of periodic replacement. Somers Washable Air Filter--All Welded Vee Type--Stock Sizes (Partial List) fFrame Sire Height and Length' - Frame Depth In. ` 24'/. \f 24Vb 21'/z 16 25 16 25 16 25 16 25 16 25 24>/z 18 18 19 20 19'/. i9y. 19'/, 20 %f 19V* 20 20 20 20 20 20 20 20 20 22o0 y, % 30 20, 5s20// 25 20'/. 3X 31/. 3* ?3V/?, 3'/. 3'/. 3% 3*/b 3J6 3% 3'/. 3 3 3'/. .3 3'/. 3 3X 3!f 3 3'/. 2 3 3 3'/. 3'/. 3 FilteSrq Surface In. 1023 1110 816 1056 1632 1344 1440 864 800 864 1482 1039 1039 936 1053 480 936 1170 1600 1800 1040 1560 1200 480 840 960 1320 1560 550 For Average Dry Filter Installation* CFM Wet Application where water sprays are applied against filter for ho' middying CFM 1023 511 1110 - _ 816 " ' 555 408 1056 528 . 1632 816 1344 672 1440 720 864 432 600 400 864 432 15 1482 741 1039 519 1039 519 936 468 1053 526 480 240 936 . 468 1170 585 1800 900 1800 900 1040 520 1560 780 1200 600 480 240 840 420 960 480 1320 660 1560 780 550 275 Other sizes from x 30 to and inclusive of 31 in. x23H also available. Send for complete stock size list. Frames zinc plated for 100 hour salt water spray test: Refill may be inserted if necessary. Quotations and further-engineering data, ineluding master holding frame drawings will be sent on request. 854 Air System Equipment Air Filters and Cleaners Westinghouse Electric & Manufacturing Co. Edgewater Park Precipitron Department Cleveland, Ohio THE PRECIPITRON* , First Commercially Practical Electrostatic Air Cleaner The Westinghouse PRECIPITRON is the first commercially practical electrostatic ,,..i,,,ri of removing dirt, dust and other air-borne impurities in ventilating and air conditioning; systems. The PRECIPITRON--more efficient than mechanical filters _irpmoves microscopic foreign matter as small as 1/250,000 of an inch in diameter FOR MASS AIR GLEANING JOBS The PRECIPITRON provides a com plete answer to ma& air cleaning jobs in all Commercial, Industrial, and Public Build ings using forced ventilation or air con ditioning duct systems. Applications -- The PRECIPITRON protects documents, decorations, merchan dise and reduces cleaning costs in com mercial and public buildings. It protects machines, stocks and production in indus trial plants. In all applications it reduces maintenance costs and improves working conditions It is used in office buildings, theatres, banks, telephone exchanges, libraries, hos pitals, laboratories of all kinds, hotels, department stores, art galleries--in fact, wherever dirt removal is important. Sizes--The PRECIPITRON is avail able, complete for installation, to accommo date from 300 cfm (for a single 18 in. cell) to any desired volume through multiple cell arrangements. Cells come in two sizes--18 in.xS% in. x 23% in. and 36 in. x 3% in. x 23% in. For a 90 per cent efficiency, the 18 in. and 36 in. cells are rated at 300 and 600 cfm respectively. For 85 per cent efficiency, ratings are 375 and 750 cfm. Two sizes of Power Packs are available. The Type S for installations up to 12 36-in. cells and Type L for 12 to 50 36-in. cells. Non-Varying Resistance--The PRE CIPITRON has no screens to clog--and its resistance is always constant. Once each month accumulated dirt is washed down the sewer with a hose. Advantages--More efficient than me chanical filters. Safe. Easily installed. Non-clogging, and non-varying resistance. Easily cleaned. Listed by'Underwriters' . Laboratories and passed by them on stand ard flame tests for fire hazard on duct in stallation. Information--Westinghouse will gladly provide complete information about the PRECIPITRON, Address your requests to Section G, Precipitron De partment, Westinghouse Electric & Manu facturing Company, Edgewater Park, Cleveland, Ohio. Trade-mark Registered in U.S.A. (See also Pages 808-809) 855 Air System Equipment Oakite Products, Inc. 22 Thames Street, New York, N. Y. OAKITE CLEANING FOR AIR CONDITIONING EQUIPMENT MAINTENANCE js RUST AND SCALE REMOVAL PREVENTING EQUIPMENT CORROSION CONTROL OF SLIME GROWTHS Cleaning Filter Screens Clean your viscous or dry-type air filter screens the Oakite way. Removal of accumulated dust and dirt is accomplished without injury to filtering medium or frame metal. Cold or hot solutions can be used. A short immersion of filter and a rinse does the job. Steam gun cleaning methods also available. Cost is low . . , full filtering capacity is restored. AIR FILTER CLEANING GENERAL MAINTENANCE Bacteria and Slime Control In Recirculating Systems Easy, inexpensive control of bacteria and slime growths in recirculating water supplies is now practical. Through the use of Oakite Airefiner; a powerful material developed by the Oakite Research Labora: tories, equipment is kept completely free of both slime accumulations and the un pleasant odors they create. Oakite Aire finer is a dry, non-volatile,' white powder,completely soluble in "water. Economical to use . . . one pound to each 300 gal of water is usually recommended. Prevents Equipment Corrosion Eliminators, air wash chambers and other metallic equipment surfaces are pro tected from corrosion when Oakite Aire finer is used, because water so treated is maintained at a point sufficiently alkaline to counteract the tendency of the water to become acidified. Air wash waters con ditioned with Oakite Airefiner - are im proved in their wetting-out power, making dirt removal more complete. Water lines are kept free of scale. . Safe Removal of Rust and Scale If feed water pipes, water cooling chambers, condensing equipment are coated with rust and scale deposits, ef ficient, low-cost operation cannot be main tained. Soaking with, or circulating a solution of Oakite Compound No. 32 provides quick, thorough scale removal, without injury to the underlying base metals. Method is easy, low-cost. Booklet on use of this widely successful material will be gladly mailed free on request. . Nation-Wide Service Oakite materials are supplied through a nation-wide group of service representa tives who are thoroughly experienced in their application. Users are thus assured of employing the materials in the way to get the full bene fits they provide. Write for FREE, interesting fact-filled booklet on the use of Oakite Airefiner and the other Oakite materials designed specifically for help ing you get the max imum life and perfor mance from your.air conditioning equip ment. No obliga tion, of course. 856 Air System Equipment u^d,fy,ni American Moistening Company `Atlanta. 9ABoston. Mass. Established 1888 Providence, R. I. Charlotte, N. C. Greenville. S. C. UNIT HUMIDIFYING AND AIR CONDITIONING EQUIPMENT A few of many AMCO products with a Long Record of Dependable Performance Sectional Humidifiers. Amtex Humidifiers. Hand Sprayers. Mine Sprays. Fabric and Paper Dampeners. Mechanical Psychrometers. Electro Psychrometers. Sling Psychrometers. Hygrometers. . The Amco line of devices for the supply, maintenance and control of humidity is comolete in its ability to meet any presented problem of applied humidification. Used independently or as an adjunct to Central Station equipment, these devices auto matically maintain any required humidity condition in a capable uniform performance. IDEAL HUMIDIFIERS--Senior Type A high capacity unit for use where conditions require a great amount and good distribution of moisture. Motor driven fan gives wide distribution of atomized spray. Amco heads serve the triple purpose of humidifying, air washing and cooling. IDEAL HUMIDIFIERS--Junior Type Similar in construction to Senior Type. Used where medium capacities are required. AMCO ATOMIZER--No. 4 Quality and quantity of spray are maintained even under adverse conditions because this atomizer is automatically self-cleaning. When the compressed air supply is shut off, either manually or in response to a humidity control, both air and water nozzles are thoroughly cleaned. AMCO HUMIDITY CONTROLS Compressed Air Operated An extremely accurate and active device operated by compressed air which assures a regulation of humidity within exceedingly close ranges. AMCO HUMIDITY CONTROL : Electrically Operated Similar in principle to the Compressed Air Type except that the hydroscopic element operates electrical contacts which control the units. 857 Air System Equipment Biliks Manufacturing Co. Plant and Executive Offices 3114-3140 Carroll Avenue, Chicago, 111. Branch Offices Cleveland, Ohio......... ...........................1740 E. 12th St. Detroit, Mich.._......................-105 E. Baltimore Ave. New York. N. Y................................... 128 Lafayette St Philadelphia, Pa................................... 2016 Market St* Los Angeles, Calif............................... 239 W. 15th St. Milwaukee. Wis..__.......................... 743 N. Fourth St. Pittsburgh. Pa.............................................. 200 Point Bide San Francisco, Calif..........................778 Brannan St New Orleans, La........................... .. ....... 329 Balter Bldg. Windsor. Ontario, Canada ' Representatives in Principal Cities . COOLING TOWERS--SPRAY NOZZLES--COOLING PONDS-- SPRAY PAINTING EQUIPMENT "Binks" Atmospheric Spray Cooling Towers "Bulks" Atmospheric Spray Cooling Towers are made in a wide range of sizes to handle capacities from 5 to 1200 gpm. They, are used and recommended for all types of industrial water cooling work and are suitable in the standard sizes for refrigeration plants ranging from 2 to 240 tons and for Diesel engine plants ranging from 30 to 3600 hp. The towers consist of a heavy shop welded copper-bearing steel frame, genuine wrought iron manifold with welded feeder arms and bronze nozzles. All metal parts are hot dip galvanized after fabrication. Louvres consist of clear all heart redwood or galvanized steel, to suit requirements. Due to standardized construction features "Binks" Atmospheric Spray Towers may be quickly erected on the job, for either ground or roof installation from a simple elevation print fur nished with each unit, without skilled factory supervision. All bolts and nuts for assembling are cad mium plated, louvres being inserted to the tower frame in slip fit louvre retainer channels requiring the use of no bolts, nuts or any other fastening. There are more than 2000 "Binks" Atmospheric Towers now in operation. "Binks" Indoor Forced Draft Cooling Towers "Binks" Indoor Forced Draft Cooling Towers are made in standard sizes from 5 gpm up to and including 300 gpm. They are extensively used for the cooling of jacket water for Diesel engines and large ca pacity air compressors, for condensing water for refrigeration ma chines and various in dustrial processes. This type of equip ment is exceptionally well adapted in loca tions where outdoor mounting of towers on building roofs would be extremely costly due to piping the installation to and from the tower. These units may be conveniently placed adjacent to the process with provision being made for fresh air inlet to the tower, such as open doors or windows, whereas the saturated air is conveyed to the outdoors through a duct. Write for Complete Catalog and Prices on any " Binks" Equipment in which you are interested. 858 Binks Manufacturing Co.____________________ Air System Equipment Towers Made in all types for every coating and industrial need "Binks" Type "K" Induced Draft Towers The "Binks" Type "K" Induced Draft Towers are designed for outdoor mounting either on ground or building roofs and are made in sizes from 25 to 2000 gpm capacity. They are extensively used for all industrial water cooling requirements and standard sizes are suitable for refrigeration work ranging from 6 to 600 tons and for Diesel engine service from 90 to 6000 hp. Fan assemblies are mounted to top of tower directly connected to geared head motors which are splash, moisture and weatherproof. Capacities of fans from 3200 to 96,000 cfm, depending on tower size, and are extremely quiet in operation, drawing air upward through tower from open louvre sections at bottom. This principle of mechanical draft tower con struction eliminates wind noises in the casing and is representative of one of the most efficient mechanical draft towers made. They are constructed entirely of galvanized steel of heavy gauge, complete with J4-in- pans, and are shipped knocked down with complete assembly drawings for field installation which can be accom plished by ordinary labor. . Spray Painting Equipment Consult Binks for any Spray Painting or Finishing Needs. Spray guns of all types. Compressed air supply systems. Compressed air cleaning systems. Spray booths and exhaust systems. Water wash spray booths; for relcaiming porcelain enamel; also for synthetic enamel and other materials. Paint supply systems: individual pres sure tanks or pipe line circulating systems. Conveyor systems for handling items to be sprayed. Complete accessory equipment for the finishing department. 859 Air System Equipment The Marley Company (Fairfax and Marley Roads,) Kansas City, Kansas Branches or Agents in Principal Cities Spray Nozzles and a Complete Line of Water Cooling Equipment *.Y Standard Water < Nozzles for Spray Prt ^sr. and Cooling Tamers. MARLEY Stnall 2-Piece Nos- sles for Brine Spraying. Air Washing and Similar uses. MARLEY IceMelting Nozzle for cooling systems using ice. marley Humi- difyingXozzleadds moisture to air in open rooms or duct system. MARLEY PATENTED NON-CLOG SPRAY NOZZLES Made in scores of types and sizes. Practically any metal or alloy the purpose may demand. Bulletins 101 and 102. MARLEY ATMOSPHERIC SPRAY TOWERS For all industrial water cooling services, refrigeration, Diesels, etc. Virtually unlimited range of sizes. Entirely shop fabricated. Low initial, maintenance and operating costs. Many exclusive MARLEY advantages. Bulletin 201. One of the small sizes of MA RLE Y Atmospheric Spray Towers. A 4~Fon example of the Marley Induced Draft Steel Tower (MARLEY MECHANICAL DRAFT TOWERS MARLEY Steel Forced Draft T-'Kt er typical of roof installations for air conditioning. Both Forced and Induced Draft Towers, for heavy duty heat-dissipating services of all kinds. Any capacity^ with one fan or many, individually engineered to the exact requirements of each installation. MARLEY patents cover a variety of important features for extreme operating flexibility, high efficiency and economy. Forced Draft--Bulletin 600 Induced Draft--Bulletin 601 MARLEY "SMALL SERIES"* STEEL INDUCED DRAFT TOWERS For jacket water cooling of engines, compressors and other small equipment. Popular in refrigerating and air condi tioning, 3 tons and up. 28 standard models for any space or capacity requirements. Vertical style for outdoor service, Bulletin 503. Horizontal style . for indoor service, Bulletin 504. Also MARLEY Spray Coil Towers, Large Induced Draft Coil Towers, Spray-Deck Type Atmospheric Towers, Spray Ponds and Related Equipment. S60 Air System Equipment spray Nozzles Jos. A. Martocello & Company 229-31 North 13th Street, Philadelphia, Pa. atomizing spray nozzles Martocello Atomizing Spray Nozzles contribute greatly to the general ef ficiency of air washing and air conditioning installations, and permit the complete apparatus to function at its maximum rated capacity. Successful--efficient oper ation of air washing and air conditioning equipment de pends largely upon having the proper design of spray nozzles. Martocello Atomizing Spray Nozzles are used ex clusively by many manufac turers because they give a uniformly fine, wide spray having a spread of 95 to 115 deg. For obtaining maximum efficiency from our Standard Spray Nozzles, we recommend with orifices as indicated in the table below. Any reason able range of capacities at various pressures can be ob tained from the sizes shown. Types of Martocello Spray Nozzles . We appreciate all difficult Air Conditioning problems being submitted to us ' for proper recommendations and results. Sizes and Capacities Pipe Size Inches Part No. Diam. Orifice Inches /. 1930 V. 1910 V, 1910 Double 1920 >/ 2300 Vz 2304 V. 2308 7/64 13/64 5/32 17/64 7/32 5/16 U/32 5 lb .22 .54 .86 1.48 1.98 2.66 3.59 101b .29 .77 1.18 1.96 2.63 3.77 4.87 Capacity, Gallon* per Minute 15 lb .34 .96 1.48 2.38 3.15 4.71 5.92 20 lb .39 1.13 1.76 2.75 3.62 5.52 6.83 25U> .44 1.29 2.02 3.08 4.05 6.24 7.62 301b .49 1.44 2.24 3.36 4.44 6.87 8.33 35 lb .54 1.58 2.44 3.60 4.80 7.47 8.98 . 401b .59 1.71 2.63 3.82 5.13 8.04 9.60 Brass Forged Nozzles illustrated and also Cast Red Brass Nozzles in 1 in. to 2 in. Pipe Size carried in stock for prompt shipment. Satisfaction Guaranteed 861 Air System Equipment su*LZe``nsf*r Aerofin Corporation 410 So. Geddes Street Syracuse, N. Y. Aero fin Standardized Light-weight Heat Exchange Surface . Branch Offices CHICAGO. NEW YORK. PHILADELPHIA. DETROIT, DALLAS Aerofin is the modern Standardized Light-Weight Encased Fan System Heat ing and Cooling Surface originated by Fan Engineers to meet the present and future requirements of this highly specialized field. All Standard Aerofin Units are furnished as completely encased Units, ready for pipe and duct connections. The patented casings are built of pressed steel and are exceptionally- strong and rigid, . protecting the Unit from all the strains of pipe connections and expansion or con traction in service. The casings are flanged on both faces, top and bottom, and tem plate punched for bolting together adjacent Units, or for duct connection. Fig. g Flexitube Aerofin (Fig. 2) is distin guished from all other developments by its off-set tubes, so arranged as to absorb all expansion and contraction strains. Headers--Cast bronze or aluminum. Tubing--% in. O.D. copper, admiralty or aluminum. Joints--Where admiralty or copper tubes are used together with bronze headers tubes are brazed to headers using Mueller patented joint. Where both aluminum tubes and headers are used tubing is welded to headers. Casings--Copper, aluminum or galvan ized iron. Design--Constructed with headers on opposite ends making possible installation of units with tubes horizontal or vertical. Aerofin Non-freeze heater (Fig. 1) is non-freeze, non-stratifying spiral fin coil built into casing for air conditioning units or for installing in ducts. May be installed horizontally or vertically. Used on any two-pipe steam system for preheating or re heating. Modulating control on preheaters. Available in 13 lengths and 3 widths, from net face area of 2.76 sq ft to 26.28 sq ft. Tubing 1 in. O.D. Innertube % in. O.D. Headers--Cast Brass. Fins--spiral, turned copper. Fig. s Universal Aerofin (Fig. 3) is distin guished by its "S" bend constructipri of 862 'Aerofin Corporation Air System Equipment Heat Transfer Surface tubing, units designed with steel headers on .opposite ends, the ends of the b bends being connected thereto by comoression nuts, the bends taking care of the expansion and contraction of the tubing. Recommended where close control is desired. Headers--Pressed steel. Tubing--1 in. O.D. Copper, admiralty or aluminum/ , Casings--Copper, aluminum or galvan ized iron. Casings--Copper, aluminum or gal vanized iron. _ Aerofin Encased Booster Units: (Fig. 5). For horizontal or vertical air flow. Six sizes, 150 to 1624 cfm. For either horizontal or vertical air flow. Fig. 6 Fig. 4 High Pressure Aerofin (Fig. 4) is of continuous tube design, being recommend ed where extremely high pressures of steam are used. Headers--Pressed steel. Tubing--1 in. O.D. Copper, aluminum or admiralty. Casings--Copper, aluminum or gal vanized iron. Narrow Width Aerofin: (Fig. 6) recommended for water cooling or for flooded Freon systems. Made in straight tubes only with headers on opposite ends, joints between headers and tubing being brazed. Construction similar to Flexitube Aerofin. Fig. 6 Booster Aerofin (Fig. 5) is of the con tinuous tube design, recommended where small volumes of air are used, or to raise the air temperatures in branch ducts, etc. Headers--Cast iron. Tubing--% in. O.D. Copper or alumi num. Fig. 7 Aerofin Continuous Tube Water Coils (Fig. 7) are designed for air cooling by circulating cold water through the Aerofin and air over extended fin surface. Made for either horizontal or vertical air flow. Tubes and fins are copper, completely, tinned with permanent metallic bond 863 Aerofin Corporation Air System Equipment Heat Tramfei Surface between fin and tubes. Headers are made of one-piece cast bronze and casings of heavy galvanized iron or copper. Units tested to 1000 lb hydrostatic pressure. Fig. $ Aerofin Cleanable Tube Units (Fig. 8) for cooling only and all made with headers removable to permit cleaning out tubes. Recommended for use where sedi ment or scale forming chemicals are present in the cooling water. Headers--Cast iron. Tubing--Copper or admiralty. Casings--Copper or galvanized iron. Fig. 9 End plate removed showing distributing and suction headers. Aerofin Direct Expansion Units: . (Fig. 9) Row Control Type--Recom mended for use where cutting on or off rows of tubes in direction of air flow is desired. Suitable for use with Freon or Methyl-Chloride. Fig. 10 Aerofin Direct Expansion Units: (Fig. 10) Centrifugal Header Type--Re commended where control of rows in direction of air flow is not required. Advantages: Weighs but 9 to 16 per cent of same equivalent cast iron surface and occupies one-third of the space. Eliminates expensive foundations and building re-inforcement. Can be suspended from roof beams or trusses if necessary. Aerofin Sizes Flexitube: 13 standard lengths, three widths, one and two rows deep. Narrow: same as Flexitube. Universal: 17 standard lengths, two widths, one and two rows deep. ContinuousTube: 13standard lengths, three widths, 2-3^4^5-and 6 rows deep. Cleanable Tube: 17 standard lengths, one width, 2 and 4 rows deep. ' Direct Expansion: Row Control--11 standard lengths, 3 widths, 1-2-3 rows deep. Face Control--11 standard lengths, 3 widths, 2-3-4-5-6 rows deep. Centrifugal Header--11 standard lengths, three widths, 2-3-4-S-6 rows deep. Steel Supporting Legs: 18 in. and 24 in. high. Punched same bolt hole centers as standard casings. Quickly attached. No other foundation required. Sale: Aerofin is sold only by manu facturers of nationally advertised Fan System Apparatus. List upon -request. Write Syracuse for. Heating Bulletin G-32; Direct Expansion Bulletin DE-34 on refrigeration type units; Continuous Tube Bulletin C. T. 34 for Water Cooling Coils; or phamplet on Cleanable Type Aerofin for cooling. Air System Equipment Heat Transfer Surface The G & O Manufacturing Company 138 Winchester Avenue New Haven, Connecticut CSO SQUARE FIN TUBING STRAIGHT LENGTHS--U-BENDS--CONTINUOUS COILS RADIATING ELEMENTS FOR ALL HEAT TRANSFER PURPOSES G&O Finned Radiation Coils for industrial applications are available in a wide range of sizes. Universal U-lOt Standard IVo. 10 Send for Catalog and Price List THE use of INDIVIDUAL fins results in high efficiency in heat transfer from primary tube surface to secondary fin surface. Fins of any size or shape may be obtained giving any desired proportion of primary and secondary surface. . A square fin has about 30 per cent greater surface than a round fin of a diameter equal to one side of the square. Individual fins permit of any fin spacing: also, of using fins in groups at intervals along tubes. STANDARD SIZES O.D. of Tube Fin ' Size Fin Spacing Surface Lraar Foot A--Generous Fin Collar provides large . contact area between Tube and Fin. B--Tube expanded against Fin Collar; insures mechanically tight joint, made permanent by bond of high tempera ture alloy--complete thermal contact. C--Free air-flow passages; non-clogging. 865 Vs' Vs" Vs' Vs' r Vs'soVs'Vd. V/l' r'd. iy* *s2Vs' sq. . 6 6 6 6 0.80 aq. ft. 0.60 aq. ft. 1.55 Ki- ft. 2.40 sq. ft. 4.00 aq. ft. An System Equipment Baker Ice Machine Co., Inc. Omaha, Nebr. MANUFACTURERS OF INDUSTRIAL AND COMMERCIAL REFRIGERATION AND AIR CONDITIONING Sales and Service in All Principal Cities Cable Address: BAKERICE AUTHORITY ON MECHANICAL COOLING FOR 35 YEARS Baker equipment is world-famous for high quality. Every machine and cooling assembly is precision manufactured and designed to provide maximum service, dependability and economy per dollar invested. Write the factory for complete specifications and descriptive literature. Baker Freon Baker or Methyl Chloride Units Complete Freon Units Avail able in 6 line of self-con models, tained, auto 20 to 60 matic units. hp inclu From }4 hp to sive, 4- 15 hp capacity. cylinder, 2- and 4-cylinder types. self-con Air- or water-cooled. tained, automatic units. Shell and tube Baker Self-Contained Air Conditioner condenser-receiver. Pressure lubrication from gear type pump. Includes self-contained removable condensing unit with Freon compres sor, shell and coil con denser-receiver, large area filter, slow speed centrif ugal type fan, continuous fin type cooling coil. At tractive bronze metallic finish on cabinet. . Baker Evaporative Condensers Compactly designed, re duces water costs. Heavy metal casing, non-corrosive type eliminators. For in door or outdoor installations. Baker Dual Condensing Units Designed especially for variable load requirements. Dual 4-cylinder type watercooled Freon unit. Automatic capacity control. Equipped with shell and tube type condenser. Baker Shell and Tube Conden ser s and Liquid Coolers Horizontal multipass or vertical shell and tube construction. Complete range of sizes. Code welded, standardized design, seamless steel tubes or hard copper tubes. Baker Dual Compressor Units for Capacity Control 19 different models, 10 hp to 120 hp inclusive. Two separate 4-cylinder com pressors, automatic controls, independent motors, pressure lubrication, panel type gage board. For use with separately mounted shell and tube or evaporative condenser. Air System Equipment Refrigerating Machinery Brunner Manufacturing Company Utica, New York, U. S. A. - For Years the Symbol of Quality The Brunner line of refrigeration equipment includes Air Conditioning models up to and including 25 hp for all types of high temperature applications within their capacity, using either `'Freon-12" or Methyl Chloride as refrigerant. The Brunner field sales organization is available in all parts of the country, backed by outstanding achievements in engineering, and adoption of modern methods and design of air conditioning equipment. Installation of Brunner refrigerating units is insurance of the finest quality of materials and workmanship--plus the highest efficiency possible in modern design and manu facture. . .. Model No. SPECIFICATIONS CAPACITIES ' Air Conditioning Units Based on 75 F Water Temperature "Freon-12" Refrigerant DIMENSIONS Hp CyU. Bore & Stroke Rpm Btu per Hr 40 Evap. Temp. L.Wit W 300-FH W 500-FH W 750-FH W 1000-FH W 1500-FH W20000-FH W25000-FH 3,5 ' . 71/, 10 15 20 25 4 4 4 4 4 4 4 3'/, x 2'/, 4'/. 3 "" 4>/,5 260 420 260 350 525 435 540 38547 62270 91526 123211 184815 255046 316652 . 47' 23V2' 27' ... \ * 60' 30* 39' ** "*" 721/,' 3U/,' 47V,' o a Additional air and water cooled models from X hp for commercial and industrial applications. BRUNNER DEPENDABILITY . ... is based on time-proven features of design and manufacture ... all parts are precision machined within extremely close tolerances . . . bronze bearings throughout . . . extra large fin surface on cylinders and heads ... bellows seal . . . silent eccentric drive (except on 20 hp and 25 hp models, which employ crankshaft) . . . suction and dis charge valves in "all-in-one" plate as sembly . . . heavy-duty motor with high starting torque . . . adjustable motor base . . . multiple V-belt drive. Through out, Brunner Refrigeration Units are geared to the demands of heavy-duty service. Completely illustrated catalog on request. 867 Model W-S5000-FH Air System Equipment Curtis Refrigerating Machine Company Division of Curtis Manufacturing Company 19 Kienlen Ave., St. Louis, Mo., U. S. A. Established 1854 93 Condensing Units from 1/6 to 30 hp Unit Coolers and Evaporator Coils PRODUCTS: Refrigerating Machinery; Forced Draft Cooling Units; Cooling Coils, Condensers, Shell and Tube Coolers, Valves, Fittings and Accessories,. Complete Refrigerating Equipment for Dairies, Creameries, Ice Cream Cabi nets, Ice Cream Making Plants, Cold.Storage Locker Systems, Walk-in Coolers, Drinking Water Systems, Commercial and Low Temperature Cooling, Pro cessing and Air Conditioning Installation, Packaged and Remote Types. Commercial Refrigeration hp Air Cooled Condensing Unit. Other sites from K to 6 hp. 48 air cooled condensing units from to 5 hp, inclusive, and 45 water cooled units from Yz to 30 hp, inclusive. All models available for either Freon (F-12) or Methyl Chloride. Mechanical ad vantages include Timken Bearings, Centro-Ring Positive Pressure lubri cation. / to hp Self-Contained Con densing Unit. 5 hp Water Cooled (Countcrfiow) Condensing Unit. Other sizes from X to 6 hp. 7)6-10-15 ton Complete Remote or Central Type Air Conditioner. Special modelsareavailable for ice cream, frozen food cabinets and for the dairy industry. ' 15 hp Cleanoble Shell and Tube Condensing Unit. Other sizes ' from S to SO hp. . Air Conditioning For stores, offices and all types of commercial es tablishments Curtis offers complete packaged, re frigerated air conditioning units, requiring only water and electrical connections to install. Cools, dehumidifies, circulates and Biters the air. Eliminates costly installation ex pense. Adaptable for heating. 868 3 and 5 ton Packaged Type Air Conditioner. Air System Equipment Refrigera ting Machinery Albany Atlanta t-- Baltimore Boston Buffalo Charlotte Chicago 'Cincinnati Dallas Detroit Frick Company (Incorporated) Air Conditioning, Refrigerating and Ice-Making Equipment Waynesboro, Penna. Distributors in 150 Principal Cities Kansas Cirr Los Angeles Mekfbib New Orleans New York Oklahoma Citt Palatka Philadelphia Pittsburgh Sr. Louis Seattle air conditioning We furnish complete air conditioning sys tems as well as refrigerating machinery for use with equipment supplied by others. More than a thou sand installations attest the value of the various Frick systems of air con ditioning, some of which are patented, and of those made under the patents of the Auditorium Conditioning Corp. Ask for Bulletin 505, describing the Bve principal kinds Frick Unit Air Conditioners, of systems; also built in two sizes, are part of the complete lino of Pnck Air Conditioning Equipment Bulletins 504 and 512, illustrating and listing typical jobs. Estimates cheerfully furnished. FRICK FREON-12 REFRIGERATION Includes a complete line of enclosed type Freon-12 compressors. Large capa city, ample gas passages, pres sure lubri cation from internal pump, patented FLEXO- New Bankers Life Budding, in Des Moines, Air Conditioned with 660 tons of Prick Freon-tt Refrigeration SEAL at shaft. Coils, coolers, condensers and controls for Freon-12 systems. Bulletin 508. AMMONIA REFRIGERATION Machines in all capacities from Y ton up. Combined unitsand verti cal enclosed type compres sors; complete high and low sides. Widely used for air conditioning, with material The Standard Carmel Company of Lancaster, Penna., has used Frick Ammonia Refrigeration for Air Conditioning Since 1910 savings in power. The Philcade and Philtower buildings in Tulsa, Okla., using 1000 tons of refriger ation, are typical of the many air condi tioned with Frick ammonia systems--with important savings. Ask for Bulletins on the sizes of machines in which you are interested: Nos. 104 to 651. LOW PRESSURE REFRIGERATION t0-Ton Freon-18 Unitfor Air Conditioning Work Commercial units in more than 50 sizes and types, with motors of Y to 30 hp. Charged with Freon-12 or methyl, chloride. Air and water cooled conden sers. Finned coils, fan and blower units, air conditioners. Bulletins 97 and 100. SERVICES Offered to the industry include surveys, recommendations, literature, estimates, sales, manufacturing, installation, test and maintenance. Frick Branch Offices and Dis tributors are located throughout the world. Enclosed Type Ammonia Compressor 869 Frick Enclosed Freon-}8 Compressor Low Pressure Refrigerating Units. Air System Equipment Refrigerating Machinery GENERAL REFRIGERATION CORP. Dept. H.V.A.-40 Beloit, Wis., U.S.A. Commercial Refrigeration Cooling Units Air Conditioning Units Refrigerating units in Air or Water-Cooled types -LIPMAN Equipment for air conditioning and commercial refrigera tion includes appara tus for practically every type of service --a great variety of models in a wide range . of capacities. Refrigeration Units are available in air or water-cooled types, for use with accepted and _ popular refrigerants. Types and Capacities Methyl ChlorideK to 5 hp Freon-12__ ;..........% to 30 hp Ammonia_______ 1 to 40 hp Small sizes are self- contained and fully automatic; larger sizes are available with manual control op tional. . A size and type to meet every need. Ammonia. Methyl Chloride, Freon-tS Air Conditioning Units are furnished in both floor and ceiling types for use in stores, restaurants and other commercial establish ments. All units are self-contained and are shipped ready to install and operate--controls are adjusted before shipment. .' Store Coolers available in ! popular sizes. Self-contained Cooling Unit. Ceiling Type Cooling Unit. DEALERS: DISTRIBUTORS: The market for GR-LIPMAN Equipment is as broad as the field for air conditioning and commercial refrigeration. A complete line of dependable, economical equipment, backed by a thorough going engineering service, and aggressive sales and advertising cooperation. Write for details on GR-LIPMAN Equipment. 870 Air System Equipment - MaJh%yne Mario Coil Company 6135 Manchester Ave.t St. Louis, Mo. Manufacturers of Complete Line of Low Side Equipment Brine Spray Units--Unit Coolers--Evaporative Condensers--Low Ternperature Units--Air Conditioning Units--Heating and Cooling Coils. Brine Spray Unit For application wherever defrosting is a problem. Designed to maintain tempera ture below freezing. See complete details in Bulletin No. 392. Evaporative Condenser ` A complete self-contained condenser, having single motor drive for fans and pump. Coil all prime surface. Frame electric welded and gal vanized. after fabrication. All internal surface covered with corrosion resistant mastic. . Full details in Bulletin No. 394. Low Temperature Unit Designed for maintaining sub-zero"temperature. Defrosted manually or auto matically by electrically heated units. See details in Bulletin No. 392. Air Conditioning Units Air Conditioning Units in either ceiling suspended or floor type. Capacities from 900 cu ft to 12,000 cu ft. Sturdily built on angle welded iron frames of sectional design for easy installation. Bulletin No. 397 gives complete details. Air Conditioning Coils--Blast Coils Extended surface coils for all refriger ants. Made of any of the common metals. Blast coils for steam, water, or brine. Complete details in Bulletin No. 396. Unit Coolers Units sturdily built in cast aluminum housing. Available in nine sizes for direct expansion or brine circulation. For use with all common refrigerants. Full details in Bulletin No. 392. 871 Refrigera ting Air System Equipment Machinery Servel, Inc. Electric Refrigeration and Air Conditioning Division Evansville, Indiana AIR CONDITIONING Air System Equipment * UNIVERSAL COOLER CORPORATION Detroit, Michigan Automatic Refrigeration Exclusively Since 1922 Servel concentrates its engineering and manufacturing, facilities on. refrigerating machines for use in the air-conditioning ' indBuasctkrye.d by 18 years of experience in building heavy-duty low-pressure refriger ating machines, Servel units offer every modern feature, plus a record, of proven deTphenisdaybeilaitry, . for the first time, Servel offers a series of compact, highly special ized Freon units for self-contained store remote models - "-v : .- coolers. ..These all carry 4--or 8-cylinder compressors, dynamically balanced, with provisioHMor full ^floating suspension, and are extremely compact. : A p.. ' For remote applications; ServCl offers a full line of unit&r-botH'' air-cooied and water-cooled--rangingiri* capacity from % ton to 20 tons. As a result of recent advancements in material and :design, these models set a new standard for com pactness, quiet operation, and freedom from vibration. COMPACT MOPELS-For Store Coolers Also available in air-cooled models. 872 flUusLrated above. Model W-1500, 15 hp Condensing Unit. A complete LINE of CONDENSING UNITS AND COMPRESSORS MANUFACTURERS: We offer you a complete line of commercial condensing units and compressors. Our unique policy of selling to manufacturers only is ideally suited to your business. Our products are accepted by nationally and internationally known makers of refrigerating and air conditioning equipment. Data and quotations sent promptly at your request. ARCHITECTS AND ENGINEERS: We will gladly send you descriptive matter and technical capacity and performance data on our condensing units. You can use this information with confidence in preparing your own specifications for refrigeration and air conditioning work. CONTRACTORS: These splendid refrigerating Machines are available to you through many of the leading manufacturers of refrigerating, air conditioning and fan equipment. We maintain no local dealers or branches to compete with you in contract work. We.will gladly send complete data. Universal Cooler Corporation, Detroit, Michigan. Universal Cooler Company of Canada, Ltd., Brantford, Ontario. , Listed under Reexamination Service of Underwriters Laboratories, Inc. 873 Air System Equipment Worthington Pump and Machinery Corporation WORTHINGTON Carbondale Division Atlanta Boston Buffalo Chicaco General Offices: HARRISON, NEW JERSEY Cincinnati Cleveland Dallas Denver Detroit El Paso Houston Kansas City Los Angeles New Orleans New York Philadelphia Pittsburgh St. Louis St. Paul San Francisco Representatives in Principal Cities o) Foreign Countries Seattle Tulsa Washington CAO-I REFRIGERATION SYSTEMS FOR AIR CONDITIONING IN COMFORT COOLING OR INDUSTRIAL PROCESS Complete refrigerating systems for use with "Freon-12," Methyl Chloride, Ammonia, or Carbon Dioxide, either direct-expansion or water cooling applications. A complete line of refrigeration compressors, permit ting impartial recommendations. A nation wide organization of Distributors in major cities to provide sales and engineering service and plan complete air conditioning systems of the central or unit type. Archi tects, Engineers, and Contractors are in vited to consult with us. Write to Harrison, N. J., or any branch office, for bulletins on these products. Small Self-contained Units Vertical Ammonia Compressors "Freon-12" or methyl chlo ride condens ing units; motors up to 25 hp; ratings up to 25 tons. Pressurelubricated ; roller main bea ri n gs ; safety heads; patented Feather Valves; belt Overall Dimensions Smallest: 22 in. long. 16 in. wide, 17 in. high Largest: 9$ in. long! 40 in. wide, 41 ill. high drive, or di rect-connec ted to electric motor, Diesel Medium Self-contained Units . or gas engine; ratings from`2 to 160 tons \ -i.v "Freon-12" in one unit. Jl;ior methyl I Overall Dimensions (Without Motor) chloride 1 Smallest; 2ft 3 ifi. Jong, 2 ft >^in. wide, 3 ft 3>i in. high Largest: 6 ft 7)4 in-, long, 5 ft wide. 7 ft 7)4 in. high " " units, equip ped with ca pacity con Vertical Duplex trol; patented Feather Double-acting Compressors Valves; mo "Freon-12" tors of 30, 40 or ammonia; and 50 hp. large tonnage compressors; force-feed Large Self-contained Units lubrication; roller main "Freon-12" bearings. refrigeration Crankcase units util sealed from izing the cylinders, new, modern preventing eight-cylin contamina der V-type tion of oil by compressor refrigerant. built into a Equipped compact unit. with patented Feather Valves; automatic V-belt or direct motor drive. Variable capacity control features. Crosshead in capacity control. Motors of 75, 100, and corporated in enclosed crankcase. Capa 125 hp. cities up to 400 tons. 874 Air System Equipment jhuchtnBtinA Worthington Pump and Machinery Corporation, Carbondale Division Horizontal Ammonia Compressors Air Conditioning Units For Direct Expansion or Water Circulation Single and duplex; single-stage and twostage; belt drive, or direct-connected to electric motor. Diesel, gas or steam engine; patented Feather Valves; ratings from 60 to 750 tons. Automatic capacity control features are easily applied. Space require ments vary depending upon type and drive. Carbon Dioxide Compressors A series of convenien t types and sizes for every re quirement is available. Liquid Cooling Equipment lHHi -- --<1 Various de . Vertical and horizontal; 500 to 15,000 cfm; large air pas sages; slow speed, quiet rugged fans; heavy welded steel frames; separable sec tions; readily accessible. The design permits a wide degree of flexibility in installation arrangements. Shower Condensers A combined con denser, receiver, and modified cool ing tower, in one as sembly, for "Freon12'1 o r met hy l chloride systems; 5 to 50 tons re frigeration; built in separable sections; all parts easily ac cessible. Saves 90 to 95 per cent in i cost of water. signs of horizontal single and multi-pass types, for a wide range of services; also verti cal types. Chillers for oil dewaxing. Single and double-pipe for milk, wort, chemicals, etc. Cold liquidcirculating systems. Steam Jet Water Cooling Systems . Horizontal Condensers '.......... # * -;.W3 Atmospheric drip type, for warm corrosive waters. Double-pipe for closed systems, can be retubed without shutting down. Multi-pass for closed systems and space saving. 15 to 600 tons. Either surface or barometric condenser may be fur nished. Vertical Condensers The Carbondale "Spira-Flo" possesses the advantages of both the atmospheric and double pipe types. Usable with any kind of water. Compact; installed indoors, outdoors, or on the roof. Easily cleaned. Miscellaneous High and low side equipment for, every purpose. 875 Air System Equipment Machinery The Vilter Manufacturing Company Since 1867 Milwaukee, Wisconsin AIR CONDITIONING EQUIPMENT FOR INDUSTRIAL OR COMFORT COOLING COMPRESSORS OF MODERN DESIGN Ammonia "Freon 12" Methyl Chloride Compressors by Vilter are the result of nearly seventy years of research, development and experience gained through thousands of installations in sizes from Vi H.P. to several ' hundred tons. These installations cover a range of applications from the most simple comfort cooling installation to the exacting requirements of temperature and humidity control necessary to the successful operation of certain industries. The Vilter "Freon 12" Compressors embody many outstanding new features two of which are of major importance and exclusive--a new, Vilter developed, shaft seal which prevents leakage, and the elimination of certain friction factors which result in exVtreilmteerlyAloirwWrealasthiveersh--ordseespigonweedr pfoerr itnodnu. strial air conditioning. Positive control of humidity, temperature, and circulation of air. Automatic or hand operated. Eliminators are incorporated for entrained moisture removal. Odors and dust are removed by water sprays. No filter replacement. Low cost operation. Good for low or high temperature cooling. __ . Vilter Mono-Unit Air Conditioners--are built in a complete range of sizes and types from small ceiling units to large floor units. . - For refrigeration and air conditioning projects Vilter can supply the equipment. UNIT AIR CONDITIONERS Dry Cofl Spray Type Air Washer 3U r . frrv. -- -- e r ~ - - . . available for the asking. . Whether the application requires a standard unit conditioner of the dry coil or spray type or a large central system of the Washer type, Vilter Equipment of sturdy construc tion and ample capacity is available. 876 Air System Equipment fans and Blowers Autovent Fan & Blower Company 1809-23 N. Kostner Ave., Chicago, Illinois " FANS -- BLOWERS -- UNIT HEATERS Member National Association of Fan Manufacturers and Industrial Unit Heater Association AUTOVENT "31 Series" PROPELLER FANS Exclusive Autovent Design --will not churn air or over load motor. Ruggedly con structed for indefinite economical operation under severe conditions. Available for quiet v* operation. Capacities from 500 to 38,000 cfm. Bulletin No. 200-A. AUTOVENT "BW" PROPELLER FANS A slow speed operating bucket wheel type fan. Provides efficient ventila tion for unlimited uses from 500 to 40,000 cfm. Sturdy con struction. Minimum power. Quiet oper ation. Bulletin No. 202-A. ACID-MOISTURE PROOF PROPELLER FANS For use where corrosive acid fumes or excess moisture exists. All exclusive Auto vent features. Available with Bakelite lacquer protective coating for average condition or a new, Heresite Chemical (375) baked finish for severe cases. Bulletin No, 201-A. VAPOR-EXPLOSION PROOF PROPELLER FANS COOLVENT FANS Solve the low cost summer comfort cooling and venti lating problems, for homes, stores, of fices, factories! Bearings and motor are rubber mounted to insure quiet operation. Built in sizes from 24 in. to 54 in. Write for Bulletin. Safe ventilation regardless of the dust or fume hazard. Non-ferrous fan wheels and chemical coatings furnished to require- , ment. Underwriters Label Class 1, Group AUTOVENT UNIBLADE VOLUME BLOWERS D. Motors. 12 in. to 36 in. fan sizes. Bulletin 201-A. Motor driven--universal discharge for fume hoods, AUTOVENT Super-Type Steam UNIT HEATERS chemical labs, processing, drying, forced draft, etc. Handle low vol umes of air at medium pressures. Wheels This suspended type heater range from 6 in. to 11 in. diameters-- forces air circulation and same design as heavy duty blowers. Can directs warm air to lower be mounted on floor, wall or ceiling. Direct part of room. Heating ele Connected Blowers for general ventilating ment of fiat copper fins, attached to applications available in wheel diameters seamless, drawn copper tubes. No welded up to 25 in. Bulletin No. 300. or brazed joints in coil or header. Fans have non-overloading power feature. Motor furnished to requirement. Capa cities from 18,200 Btu to 398,500 Btu. AUTOVENT UNIBLADE TYPE "H" ySH ^1 AUTOVENT "V" BELT DRIVEN or "HB" BLOWERS : Ideal for ventilating and UNIT BLOWERS air conditioning installa- Forwardly curved blades. Quiet bearings. Motor mounted on steel pedestal, integral with blower housing. Air delivery tionsfeaturingbackwardly inclined blades and non-overloading power characteristics. Also comes with forwardly curved blades. Belt driven, centrifugal can be decreased or increased. Inter type in single or double widths with 12 ^ in. changeable motors. Sturdily constructed to 75 in. wheel diameters. Can be furnished of sheet steel, rolled lock seams. Bulletin to any speed or discharge requirement. No. 300. . Bulletin No. 301. Backward curve type HB Belt Driven Blowers, Bulletin No- 302. The Complete Line of Autovent Propeller Fans and Blowers is tested and rated in ac cordance with the Standard Test Code adopted jointly by the National Association of Fan Manufactures and the American Society of Heating and Ventilating Engineers. 877 Air System Equipment m Fans and Blowers American Coolair Corporation Jacksonville, Florida Cooling and Ventilating Fan Systems For Homes, Offices, Stores, Factories, Etc. A Pioneer Manufacturer of Attic Fans for Home Cooling Charter Member--Propeller Fan Manufacturers Association COOLING BY AIR MOVEMENT Engineers and architects know well that people working or living within a building can be kept cool, healthfully and economically, by sufficient `movement of fresh air. It is not so well known, perhaps, that such cooling requires four to eight times the volume of moving air needed for simple ventilation. Satisfactory cooling requires a com plete air change in working or living quarters at least once a minute. The American Coolair Corporation pioneered in the manufacture of attic fans for home cooling and during the past 12 years, Coolair engineers have been directly responsible for many of the develop ments in this field. In planning a Coolair installation, determine cubic content of space to be cooled or ventilated and select fan of ample capacity based on the table of Recommended Air Changes shown. Write for Coolair's FREE catalog containing detailed instal lation suggestions for home and commercial jobs. Coolair Type 0, showing new built-in springs. Ideal for attic, window and wall installations in homes, offices, restaurants, stores, etc. FEATURES OF COOLAIR FANS Coolair Type S, diameters 6 to 9 ft, capacities up to 150.000 cfm. Used in hotels, factories, auditoriums, etc. 1. New Built-In Springs--completely insulate moving parts from frame, eliminating vibration noise. Simplify window, wall and attic installations. 2. Light, Com pact Fabricated Steel Frame--fits into many places where fans with bulky metal housings cannot be used. Easy to handle and install. 3. Reversible--^when equipped with reversible motor, fan will blow in or exhaust at will. 4. Ball Bearings in Fan Hub-- Eliminate sleeve bearing chatter and end thrust knock. Permit operation in any position (specify ball bearing motor for vertical or angle discharge). Uses grease instead of oil, requiring attention only once a year (once each three years for residential service). 5. Eight Large, Slowly-Moving Steel Blades--instead of four or less usually found on cheaper fans. Up to 12 blades on Type S models. Low tip speeds for quiet per formance, steady flow of air. 6. Efficient V-Belt Drive--and small motor for efficient operating speed. 7. Efficient Long Hour Service Motors--rubber mounted on adjustable support. Nation ally known make approved for this application. 8. Certified Air Ratings--in accordance with Standard Test Code of NA FM and ASHVE. 9. FiveYear Guarantee on Resi dence Fans (belts and motors 1 year). 878 Coolair Type T, space-saving, efficient twin unit widely used where headroom is limited. Shown with new built-in springs. U. S. Potent No. ,108,788 American Coo/air Corporation Air System Equipment Parts and Blowers Performance Data--Coolair Belt Drive Fans . Fan Size 2-0 26" 2'AO 32' 3-0 . 38' j B C D B C D D B C D 334-0 44' 4-0 50" 4'M> 56' . B C C D B C D D B C D .B 5-0 C C D D Hp | Fan rpm XL 448 y,y 1 535 X 595 X 395 X 432 X 495 X 567 X 308 X 335 X 394 X 440 485 . X 244 X 294 X 325 1 358 IX 410 X 248 X 290 1 320 IX 366 X 210 X 236 1 250 IX 298 2 328 X 175 X 201 1 222 IX 254 2 230 3 . 321 , 1 Cu Ft Air Per Min 4600 5500 6100 7500 8200 9400 10700 10000 10800 12800 14200 15700 12500 15000 16600 18300 21000 18200 21300 23500 26800 21800 24500 27000 30900 34000 24600 28200 31200 35700 39300 45100 vnumes, ineaters, Hospitals, etc). C--Quiet (Stores, Offices, Restaurants, Barber Shops, etc.). D--Industrial (Laundries, Factories, Canneries, Bakeries. Pressing Clubs, Garages, etc.). Fan Size Hp Approx. Fan rpm Cu Ft Air Per Min 6-S 72' B C \x 171 190 C2 206 D3 263 32000 35500 38500 49000 D 5 306 57500 7-S 84' B2 C3 D5 163 49500 176 53500 227 72000 D m 262 80000 8-S 96' B3 C5 D 7X D 10 147 176 204 259 66500 80000 93000 117000 9-S 108' B5 C 7X D 10 D 15 150 165 193 230 96000 108000 128000 150000 2-OT 26' Twin B C X 450 X 514 9400 10700 234-OT 32' Twin B C X 393 X 450 15300 17500 3-OT 38' Twin B C X 295 . 19200 X 337 21800 3J4-OT B X 257 44' Twin C 1 283 26200 28800 4-OT 50' Twin B C 1 234 34600 270 40000 Recommended Air Changes Type Building Air Change in Minutes for Cooling Ventilating Bakeries. Boiler Rooms, Canneries, Pressing Clubs, Laundries. Restaurants, Kitchens. F.tr. X-l 2-5 . Barber Shops, Beauty Par lors, Billiard Rooms, Bowling Alleys. Garages. Factories, Restaurants. Stores. Etc. . X-IX 3-6 Auditoriums, Churches, Club Rooms. Schools, Theaters, Etc..................... X-IX* 4-8** Homes,-Apartments, Hotels, Hospitals, Offices, Banks, Undertaking Establishments, ^.................................. X-2 | 4-8 When based on seating capacity, allow 150-200 cfm per person. % Minimum on basis of seating capacity is 35 cfm per person. COOLAIR DIRECT DRIVE FANS Fan Size 2-OT 2^-OT 3-OT 3M-OT 4-OT AB 30X 36X X 49 55X 4 m m nt *6 c 9X 9X m I0X I2X D Approx. E 13 6IX 13 nx 14 85X 17 98 19 II0X Coolair Direct Drive Fan 16-84 *n. Manufactured in . four sizes from 16 to 24 in. in diameter. , Positively quiet at 120Q rpm, not ex cessively noisy at 1800 rpm. Unique noise-reducing de sign of blade is cov ered by U. S. Patent No. 1855660. WRITE FOR FREE ILLUSTRATED COOLAIR CATALOG 879 Air System Equipment * fans and Blowers Bayley Blower Company 1817 S.-Sixty-Sixth Street Branches in principal cities Milwaukee, Wis. Builders of Heating, Ventilating, Cooling, Purifying, Humidifying and Air Washing Equipment; Exhaust and Drying Apparatus, Mechanical Draft and Blast, Fans and Blowers of all Types Bayley Plexiform Fan; Is a multi-blade fan for supplying air for heating and ventilating systems, manufacturing processes, drying systems, forced and induced draft systerns. It is suitable for handling high or low temperature gases at medium or low pressure. Will deliver maximum quanti ties requiring minimum space with great economy. This is a distinct Bayley product, high class material and workmanship, properly designed to avoid excessive vibration and overstressing of parts. Inlets and outlets are properly sized for maximum delivery and maximum efficiency. Fans are fur nished in single or double width of any required arrangement and with sleeve or anti-friction bearings. Aeroplex Fan: Is of high speed design with self limiting power characteristics. Application parallel to the Plexiform Fan. Highly efficient and quiet in operation. Bayley Exhausters and Pressure Blowers: Type "B" exhaust fan is for heavy duty, hand ling refuse from industrial and textile plants. Type "SE" is used in handling smoke, fumes and dust laden gases. Type "H" for high-pressure work. These units are highly efficient and of high class design and workmanship. Bayley Turbo Air Washers, Humidifiers and De-Humidifiers: The Turbo At o m i ze r used in.-, the Bayley Washer pro duces a . steady, fine spray. Water at low pres sure is deliv ered to the Center of a The Bcytcy Turbo Air WathtT Show- inff Turbo Atomizer and Eliminator rapidly re volving cone-shaped rotor provided with atomizing pins set in its periphery. This atomizer requires very little attention, and will operate successfully under low water pressure. The orifices are large and this atomizer, unlike high pressure nozzles, cannot clog. Bayley Chinook Heating Sections: The Chinook sec tion is used with blast heating, venti lating and drying systems, and is suit able for high or low pressure steam cir culation. The base is divided into two chambers. Steam enters (see cut) the lower chamber, ris ing through J^-in. pipes located within the lj^-in. pipes leading from the upper chamber. Condensation takes place in the larger pipes, the water falling into the upper chamber and draining away through the return outlet. The Chinook can be repaired in the middle of the bank without breaking steam connections or taking down a section. Shipped assembled in smaller sizes, and knocked down in the larger units. May be installed in horizontal or vertical position. Bayley Chinookfin Heating Sections: Are the same design as the Chinook Heaters, using heavy gauge copper fin tubes. As compared with Chinook it is much lighter and occupies less space. Bayley Plexfin Unit Heaters: This unit incorporatea Chinookfin radiation and Plexiform or Aeroplex fans. The fan assem bly including top plate and motor is re movable as a unit for main tenance and inspection. The heating element is a re movable unit. Casing all welded extra heavy gauge. This is an exceptionally high grade unit at a moderate price. 880 Air System Equipment * Bans and Blowers Buffalo Forge Company 450 Broadway, Buffalo, N. Y. Branch Offices Albany, N. Y............. Atlanta, Ga............... ' Baltimore, Md... . Boston. Mass............ Chicago. III.___ . Cincinnati, Obio._.... Cleveland, Ohio____ ............. 1305 Standard Bldg. ...1454 Pifdmont Ave.. N. E ...................... 508 St. Paul St 486 Main St. ....... 20 North Wacker Drive ........ .....-.......-626 Broadway ------ ....418 Rockefeller Bldg. Knoxville, Tenn.--C. F. Sexton..... ........702 Empire Bldg. Los Angeles. Cauf......... .............708 Perabing Square Bldg. Minneapolis, Minn................................... 2102 Fosbay Tower Nashville, Tenn.--Southern Sales Co., New Orleans, La.--Devlin Bros..... -.1101073FMiftahritAimvee. SBoldugt.h DDAaLlLlAaSs,, TTEeXxAaSs. .............. lowe.7r0r2eirTooiweueiruPueutriogl.eum Bids. New York. N. Y-------------39 Cortlandt Bldg., Room 1110 Davenport, Iowa-- D. C. Murp-khy~ Crio-., 3in0c5 S<S~e-c---u--rDityIJB. ldg. Philadelphia, Pa.......... ..................... ............703 Cunard Bldg. Denver, Colo.4--Hendrig 4 Bolthofr Mfg. A Supply Co., PrmavBO, Pa.._-........................... ........ .......... 431 Fulton Bldg. . 1635 Seventeenth St. Dss Moines, Iowa--D. C. Murphy Co., Richmond, Va--T. Spencer Williamson, Jr., Inc., 214 Old Colony Bldg, . Detroit, Mich.--Coon DeViaser Co., 2051 W. Lafayette Blvd. Greenville, S. C.______ 312 Franklin National Life Bldg. Houston. Texas.................... .....1037 Bankers Mortgage Bldg. Kansas Citt, Mo....----------------- --_____ 428 Dwight Bldg. Kitchener, Ont., Canada-- . San Francisco, Cauf.--Moore Machinery Mutual Co., Bldg. V625 Van Ness'Ave. St. Louis, Mo............... -................................ 1598 Arcade Bldg. Seattle, Wash-------- --.......................--500 First Ave. South Toledo, Ohio---------- ---...................... 1922 Linwood Avenue Washington, D. C.--820 Woodward Bldg., Canadian Blower <k Forge Co., Ltd. 15th and H Sts.. N. W. Wilkes-Barre, Pa.--Power Bngrg. Corp., 517 Brooks Bldg, PRODUCTS: Heating and Ventilating Equipment including: Unit Heaters, Multiblade Fans, Pipe Coil Heaters, Buffalo Air Washers, Buffalo Unit Air Washers, Buffalo Unit Coolers, Drying Equipment, Mechanical Draft Fans, Air Preheaters, Exhaust Fans, Blowers, Dust Collectors, Disc Fans, Spray Nozzles. Buffalo Limit Load Fans These better fans are proving increas ingly popular in the industrial field be cause of: 1. High efficiency. 2. Dur able construction. 3. Non-overloading characteristic which means that no mat ter how much the fan load varies the motor will not overload and burn out. Fans are available with Buffalo Silent Floating Base assuring ex tremely quiet operation. Buffalo Unit Coolers Quiet unit coolersforuse with cold water, brine, . methyl chlo ride or Freon. Compact, simple, inex-* pensive. Availabte in both sus pended and floor types. Breezo Ventilating Fans Use these efficient inexpensive fans wher ever they may be installed to exhaust into the open air. Sizes from 8 in. to 36 in. in diameter. Prompt shipments from stocU. Buffalo Comfort Conditioning Cabinets Available for simple cooling, for complete air-con ditioning including winter heating. Neat, com pact units that are easy to install and easy to service. Cooling capacities--3 tons up. Fans for Every Ventilating Need For over 60 years we have specialized in designing and building fans for every con ceivable use. Write for our fan catalogs. Buffalo Air Washers For air washers whose design and perfor mance has stood the test of time it will pay you to specify "Buffalo." Bulletin 480 gives you complete details. Buffalo Unit Heaters Buffalo Unit fv Heaters are ` built in a wide range of sizes and types for the efficient and econom ical handling of any heating problem. Oper ate with either low or high pressuresteam. BreezchFinSUom Unit We also offer a . wide selection of Gas Unit Heaters that are fully automatic and equipped with every necessary safety device. 881 ..... Air System Equipment Fans and Blowers Champion Blower & Forge Co. Manufacturers and Engineers plant and offices: Lancaster, Pa. Address Correspondence to Div. 9 Manufacturers of Blowers, Ventilating Fans and Exhaust Fans for Air and Material; and Blast Gates Representatives in Principal Cities Type S Forward curve ventilating fans, single and double width, os well as direct motor drive. Ventilating Fans--For air conditioning systems and mechanical draft. Manufactured in the forward curved type for slow speed, and extremely quiet operation; also in the backward curved type with its fiat horsepower curve characteristics and higher speeds suitable in the smaller sizes for direct connecting to synchronous speed motors. Ventilating Blowers manu factured in sizes up to 60 in. diameter wheel, in single and double width. Belt driven blowers equipped with either ball or high-grade babbit bearing. Direct motor drive-can be equipped with any type or characteristic motor desired, in any arrangement. Disc Fans--Super Ventilating Fans made im direct connected type up to 36 in. diameter, totally enclosed, ball thrust type motors. Slow speed motor belt driven type manufactured in sizes up to 48 in. for attic exhaust work- and wherever large volumes of air are to be moved against low static pressures! . All disc fans are quiet-:; in operation. Decibel ratings on all fans are available. Super I'entilating fans, direct motor drive up to $6 in. diameter. Motor belt drive up to in. size. Forced Draft Fans--All sizes for use on the smallest to largest boilers. Fans can be furnished with inlet or outlet adjustable louvers for controlling air volume. Blast Wheels--We are well equipped to manufacture single and double width blast wheels in forward or backward curve type for oil burner and stoker manu facturers, as well as manufacturers of air conditioning units and other ventilating equipment: Vibration Dampener Sub-Bases--For blower and ventilating equipment. Made with heavy channel iron and rubber vibration eliminator pads to suit size and weight of fan or blower. Type BC Backward curve venti lating and exhaust fans, single and double width; belt driven and direct connected electric. . Special Fan Equipment--We are in position to engineer and build fans, blowers, or exhausting equip ment to meet customers' special needs. A card ad dressed to Div. 9 will bring you complete catalog data or information on any particular problem confronting you. , 882 Air System Equipment Fans and Blowers DeBothezat Ventilating Equipment Division ^ American Machine and Metals, Inc. {Main Office and Factory) East Moline, Illinois Branches Atlanta Boston Cincinnati Cleveland Dallas Des Moines Detroit Fort Wayne Hartford District Offices New York, N. Y. Chicago, 111. San Francisco Branches Indianapolis Los Angeles Milwaukee Minneapolis New Orleans Pittsburgh Providence Saginaw : St. Louis Ventilating Fan Axial Flow Axial Flow Ventilating Sets A complete series of volume and pressure axial-flow fans of high mechanical and static efficiencies with a non overloading power characteristic. These fans offer savings in space, weight and power. Axial-Flow Ventilating Sets are available in a wide range of capacities in sizes 8 in. through 10 ft in diameter, and may be had arranged for direct motor drive or belt drive. Bifurcators . ` " , Designed for handling corrosive or high tempera ture vapors with direct motor driven fan. Motor is located in chamber open to atmosphere but isolated from gases handled by fan. Installed as integral part of duct system, in any position. ` Bifurcator 2-Stage Impeller Blower Direct Motor Drive Multi-Stage Impeller Blowers These units can be furnished in 2, 4/6 or 8 stages. Direct motor or belt driven, producing high capa cities and static pressures, with non-overloading power characteristics. Roof Ventilators DeBothezat builds a complete line of power roof ventilators of suitable materials. The above is only a partial list of the ventilating units DeBothezat builds. Our engineers will be glad to give you expert assistance in your venti lating problems--offering you a solution in space, weight and power saving equipment. Catalog on all products sent on request. 883 Air System Equipment Pans and Blower, ILG Electric Ventilating Company Propeller Fans, Blowers, Unit Heaters, Air Conditioning Equipment 2880 North Crawford Avenue, Chicago, 111. Sales Representatives In all Principal Cities GnttCi&CKcetf. ILG SELF-COOLED MOTOR PROPELLER FANS Used everywhere for removal of foul air, fumes, heat, etc. Features include: the patented Ilg self-cooled motor, dynamically balanced, vibration-free, bucket-type wheel, and a strong onenameplate responsibility. Motor, wheel and frame are all Ilg-built. The self-cooled motor design com bines the low operating cost of the open motor with the protection of the fully enclosed motor. The fan action draws clean air through vent pipe from out side; circulates it through motor (follow the arrows) and exhausts it. The llg motor staysdean, cool. Ilg fan sizes range from 12 to 72 in. in A.C. and D.C. Ratings are in accordance with the Standard Test Code of the A.S.H.V.E. and the National Association of Fan Manufacturers. . ' . OTHER ILG PRODUCTS Ilg Universal Multiblade Blowers--Type B Universal Blowers combine compactness, quietness and efficiency. Motor is recessed in side of blower, requiring no separate base. Multiblade wheel is mounted on motor shaft. There is no inlet bearing. Available also for belt drive. Capacities 1750 cfm to 70,000 cfm, single and double width. Ilg Type "B" Volume Blowers--A new design in small volume, low pressure blowers. Light weight, quiet running. Dynamically balanced multibjade wheel is mounted on motor shaft. Motor and steel housing are supported by cast-iron base. Universal discharge. Available in 11 capacities^ 180 cfm to 2100 cfm. Ilg Type "BC" Universal Blower--Motor load remains constant over unusually large variation in air volume and static pressure. - Type "BC" comes in direct connected drive {left); also belted drive with ball bearings {right). Blower wheel has back ward curved blades riveted to side and back plates. Universal discharge. Available in 11 sizes. Ilg Unit Heaters--Steam and Electric--Copper tube and fin construction and enclosed self-cooled motor. Ug-built throughout. For steam or hot water. Tested with 500 lb hydrostatic pressure. Available in 67 capacities; also, llg electric unit heaters for all electric operation, available in 20 sizes. Ilg Cooling and Air-Conditioning Units-- Self-contained Ilg Spot Koolers in 54 ton cooling capacities with water compressors. Also central unit systems using floor cabinet or ceiling suspension units with remotely located compressor. For cooling, dehumidifying, and recirculating. Also, for heating and humidifying. 884 Air System Equipment Fans and Blower, The Lau Blower Company Home and Orchard Aves., Dayton, Ohio Manufacturers of LAV Furnace Blower Package Units, LAU Blower Assemblies, LAU Blower Wheels, Housings, Variable and Constant Speed Pulleys, Pillow Blocks, Casing Mouldings, and LAU NITEAIR Attic Fans LAU 100 Series Blower Assembly A low speed, high delivery blower as sembly for manufacturers who fabricate their own casings. 20 sizes; variable speed drive; automatic belt-tightening device; automatic cut-out on motor. Rubber cushioned to eliminate noise and vibration. Also available with top motor mounting. LAU Blower Wheels and Housings Squirrel cage, forward curve, multi-blade type wheels. Double inlet, double width, and single inlet, single width. Dynamically balanced; sizes 4)4-in. to 30-in. Blower housings available in 10 standard sizes-- special sizes on request. LAU Self-Aligning Pillow Block Oil tight steel housing; reservoir holds twice as much oil as cast iron housings; Durex bushing feeds oil to the shaft by capillary action and maintains a constant oil film even when shaft is not rotating. Spherical surface of bearing conforms to contour of housing, providing a universal joint action. ^ Slotted bolt holes make LAU PILLOW BLOCKS interchangeable with . other makes. Hold-down bolts cannot affect freedom of the bearing. ' LAU Niteair Attic Fan For any type installation, in outside attic wall, or over grille or attic stairway, NITEAIR ATTIC FAN is highly effective for home, apartment, or store. Sells as fan in all metal housing with protective grille, or as Package Unit complete with all-metal fire-proof acorn stically-treated vent box and housing with ceiling grille, fusible link, automatic trap door switch, etc. No metalto-metal contacts; motor bearing support frame and fan housing mounted on rubber to absorb vibrations. Available in sizes for every type of home installation. Write for Bulletins and Prices on LAU Equipment Mentioned on This Page. 885 Air Sysiem Equipment Fans and Blowers Akron, 0. Albany, N. Y. Atlanta, Ga. B. F. Sturtevant Co. Baltimore. Md. Birmingham, Ala Boston, Mass. Hyde Park, Boston, Mass. Buffalo, N. Y. Camden, N. J. Chicago, 111. Cincinnati, O. Slurlevanl Cleveland, O. Columbus, O. Des Moines. la. Detroit, Mich. El Paso, Tex. Grand Rapids. Mich. Greensboro, N. C. Hartford, Conn. Indianapolis; Ind. ' PLANTS LOCATED IN ` Jacksonville, Fla. Kansas City, Mo. Little Rock, Ark. Camden. N. J. Hyde Park, Mass. Framingham, Mass. Sturtevant, Wis. Galt, Ont. Berkeley,.Calif. . Los Angeles, Cal. Louisville, Ky. Mansfield, O. Memphis, Tenn. The Cooling and Air Conditioning Division of B. F. Sturtevant Company . Milwaukee, Wis. Minneapolis, Minn. Montreal. P. Q. Newark. N. J. New York, N. Y. Phoenix, Ariz. Pittsburgh, Pa. Portland, Ore. Richmond, Va.. St. Louis, Mo. Salt Lake City, U. San Francisco, Cal Seattle, Wash. Spokane, Wash. Springfield, Mass. Syracuse, N. Y. Toledo, O. Toronto, Ont. Washington. D. C. A. M. Lockett & Co. New Orleans, La. Houston, .Texas Dallas, Texas Galveston, Texas HYDE PARK BOSTON, MASS. Atlanta Camden Chicago Greensboro Los Angeles New York DATA ON HEATING, VENTILATING, AIR CONDITIONING AND VACUUM CLEANING EQUIPMENT FOR ARCHITECTS, ENGINEERS, CONTRACTORS The publications listed below have been prepared to aid the architect, engineer and contractor in the selection of proper equip ment for industrial, public, and private buildings of all types and sizes. If you do not have all of these publications in your file we will gladly send copies upon request. COOPERATION MISCELLANEOUS HEATING AND VENTILATING EQUIPMENT Catalog No. ' 291 Pneumatic Collecting and Con veying Systems. . 377 Unit Ventilators. 395 Rexvane Speed Heaters (Floor type unit heaters). 396 Speed Heaters (Suspended Type Unit Heaters). . 434 Extended Surface Heating Units. 444 Axiflo Fan (Specially designed to operate against duct and wind re sistance). Sturtevant Engineers, located at each of the offices listed are always ready to co operate with architects, engineers and con tractors in the selection of equipment suitable for any prospective installation. VENTILATING FANS Catalog No. AIR CONDITIONING' EQUIPMENT Catalog No. 295 Air Washers. 398 Comfort Air Conditioning. 401 Railway Air Conditioning. 424 Fans and Air Washers for Theatres. 425 Air Conditioning Apparatus--Fans and Accessories. 271-3 Multivane Fans (Forwardly curved blade type). 414 Rexvane Fans (Radial blade type). 400 Direct-connected Fans and Blow ers (Propeller Fans; Window Fans for kitchens and offices; Centri fugal Fans from 80 to 6460 c.f.m.; Portable Gas - Engine - Driven Fans; Coal Burning Blowers; Forge Blowers; Dust Blowers). 435\ Silentvane Fans (Backwardly 442/ curved blade type). VACUUM CLEANERS Catalog No. 368 Industrial Vacuum Cleaning Systems. 373 Vortex Furnace Cleaner. 387 Vacuum Cleaner Tools and Acces sories. ; . 397 Central Vacuum Cleaning Systems (Commercial Buildings). . 413 Vortex Portable Vacuum Cleaners. 886 Air System Equipment Fans and Blowers The Torrington Mfg. Co. 50 Franklin Street, Torrington, Conn. Manufacturers of All-Aluminum Blower Wheels and Disc Propeller Type Fan Blades. Air impellers for every purpose. Torrington Aluminum Blower ^.Wheels produce the smooth, quiet per^i/ormance which is essential in modern ` Shearing and air conditioning units because the unique patented.construction breaks up resonance and minimizes noise. Made of aluminum, they resist corrosion and their light weight facilitates quick starting --saves power. Every wheel is perfectly balanced by hand and given a running test. Bulletin lists 34 sizes of single inlet single width and 34 sizes of double inlet double width wheels, including guaranteed capacities for each. Also gives detailed dimensions for all wheels and table of dimensions for housing scrolls. We do not manufacture housings. . Sizes 3 in. to 15 in. diameter in all , standard widths. Single Inlet Blower Wheel Torrington Airotor Blower Wheels are light, sturdy and inexpensive--incor porate new principles of design and con struction which insure maximum air delivery with minimum noise. End rings punched and formed in single pieces flanged to carry blades. Blades punched and formed in a single strip. Hubs rigidly mounted by peening. No rivets used. Steel with aluminum lacquer finish is standard. Present sizes: 3 in., 12 in. and 16 in. diameters. Similar wheels will soon be available in a complete range of sizes from 3 in. to 20 in. diameters in both single and double widths. Double Inlet Blower Wheel Pal. 1,700,017 Torrington Cup Type Wheels--The one piece cup construction is economical for production and the design is efficient and sturdy. Ideal where maximum air delivery and minimum power is required. Used for automobile heaters, windshield defrosters, small hair dryers, hand dryers, ice box and refrigerator circulators, win dow ventilators, exhausters, etc. Made for either clockwise or counter clockwise rotation, of steel or aluminum, in the following sizes: . Airotor Blower Wheel Diam. 3 in. 3% 'ft. n. in. 5 in. 5 m. Blade Width 1% in. U6 in. 2& in. 3 in. 2% in. 3 in. Diam. 6 in. 6 in. 6 in. 6 in. 7Kin. 9 in. Blade Width H in. 1% in. 2% in. 3% in. 4in. 4${ in. Cup Type Blower Wheel Pats. 1,513.76$ and 1,648,060 {Produced under license from American Blower Co.) - 887 The Torringlon Mfg. Co. A iristocral DcLuxc Model Airistocrat Standard Model Pals. e.<072,322 and 16,081,707 Airistocrat Air Circulator Model .4 iristocral 3-Made Onr Piece Model Air System Equipment Fan, and Blowers AIRISTOCRAT Quiet Propel ler Fan Blades are widely recognized for their all-around excellent performance. The unique, patented construction em bodies entirely new principles in the art of fan design--produces a blade unsurpassed for quiet operation, rugged construction and attractive appearance. Every Air istocrat unit is carefully built and the blades are hand gauged for correct contour and alignment. Balanced by hand, these blades deliver full air volume with a minimum of noise. Aluminum alloy blades and steel centers are standard except where otherwise noted. Rotation is clock wise only (facing air delivery side). Available in the following finishes: 1. Plain--no finish on blades, spiders or hubs. 2. Blades with no finish; spider and hub with cadmium plate or black lacquer. 3. All black lacquer, with or without center button. 4. Buff and lacquer blades, black lacquer spider and hub, with or without center button. Catalog gives detailed dimensions and guaranteed per formance curves recorded under NEMA code tests at various speeds for each of the Airistocrat models described below. De Luxe Model--The round, convex centerplate adds to the beauty of this ultra quiet blade which will improve the appearance and performance of your unit and help to sell it. Particularly adapted for use in household and office fans.' Sizes 10 in., 12 in. and 16 in. diameters. Standard Model--Same as De Luxe Model but with blades mounted on a conventional type spider instead of round center disc. A sturdy, attractive blade which has withstood extreme laboratory breakdown tests. Sizes-8-in., 10 in., 12 in., 14 in., 16 in., 18 in. and 20 in. diameters in a variety of pitches to meet every need. Priced lower than De Luxe Model. Pressure Model--Similar in construc tion to Standard Model but with blades especially designed for higher pressures. Sizes 10 in., 12 in., 14 in., 16 in. and 18 in. diameters. Air Circulator Model--The design of this blade is the result of two years of laboratory experiment to produce a better air circulator blade. At recommended speed these blades produce a high velocity air stream effecting deep penetration with unusual quietness. Sizes 20 in., 24 in. and 30 in. diameters. 3-Blade One-Piece Model--An at tractive, inexpensive one-piece blade in corporating the Airistocrat features for quiet operation. Available in both steel and aluminum. Sizes 8 in. and 10 in. diameters. 888 The Torringlon Mfg. Co. Air System Equipment Fan, and Blowers AIRISTOCRAT Attic Fan Blades are the .result of extensive study and experi ment to produce blades having extra ordinary efficiency, to sell at lower than average prices. LOW COST is possible because tools are interchangeable for pro duction of either 2, 3 or 4 blade models in any diameters from 36- in. to 48 in. inclusive (sizes 36 in., 42 in. and 48 in. are standard) and because of the sheet metal construction used throughout. EX TREME RIGIDITY, with relatively light , weight, is effected by new features of onstruction which eliminate vibration and tontribute to quieter operation. Con struction approved only after severe breakdown tests. The extremely high EFFICIENCY is attained by the appli cation of correct principles of design. Blades, spiders and hubs are of steel. Available in the following finishes: 1. Plain. 2. Aluminum lacquered blades, black lac quered spider and hub. 3. All one color lacquer. Bulletin gives detailed dimen sions and specifications; also performance data. TORRINGTON 4-Blade One-Piece Propeller Fan--An exceptionally rigid model blanked from one piece of metal with four wide blades. Quieter than nar row blade types. Made in both steel and aluminuih. Clockwise rotation only (view ing air delivery side). Sizes 10 in. and 12 in. diameters. Available in the follow ing finishes; 1. Plain. 2. Lacquered. 3. Nickel or cadmium plated (steel only). AUTOCRAT Fan Blades--For auto heaters, windshield defrosters, etc. Have been standard ever since these devices were first marketed. Made in sizes 3 in., 4 in., 4)4 in., 5 in., 5)4 in., 5)4 in., 6 in., 6)4 in., all four blades, also 7 in. 5-blade, in one piece of cold rolled steel or aluminum with brass hubs, com plete with set screw. )4 in. bore is stan dard. Either clockwise or counter clock wise rotation (expressed when looking at air delivery side of fan). White nickel is standard finish for steel blades. Bulletin gives complete specifications and ratings. TORRINGTON Pressure Fan Blades Two and four blade models of steel designed for pressure operation. Sizes. 20 in., 22 in., 24 in., 26 in., 28 in. and 30 in. diameters. 24 in. and 30 in. sizes suitable for attic fans. Performance data on a' complete range of sizes available soon. 889 4-Blade Airistocrat Attic Fan (also made in 8 and 3 blade models') 4-Blade One Piece Fan Autocrat Fan Blade 4-Blade Torringlon Pressure Fan (also made in two blade model) Air System Equipment Fans and Blowers Branch Offices in I-* J Wing Mfg. Go. Principal cities 59 Seventh Avenue, New York, N. Y. Factory: Newark, n. j. Wing Featherweight Unit Heaters--Floodlights of Heat Located near the ceiling or roof, they prevent accumulation of hot air in the upper spaces thereby avoiding costly waste of heat. . They project the air. com fortably warmed, to the working area where the heat spreads to every point. Vertical downward discharge from multiple outlets at proper velocity assures even distribution. The lightness of the units permits tneir suspension directly overhead in any location. Furthermore, one large WING unit with multiple discharge takes the place of several one-direction heaters at less cost for units, piping, wiring and installation. There is a type for every condition from low ceilings to installations as high as 55 ft. They use the WING Featherfin Heating Element described below. Bulletin H-6A. Wing Revolving Discharge Featherweight Unit Heaters Bring the realization of a heating method that produces live heat--the pleasant healthful effect of comfortably warmed air in motion.. No hot spots, cold spots or drafts because the circu lating air is continually changing direction. Eliminates difficulties encountered in certain plants where machines or other equipment would permanently or temporarily obstruct the flow of heat from a fixed discharge. Bulletin H-7. Wing Featherfin Heater Sections For heating or cooling air for any purpose'bysteam, hot water, cold water or refrigerant. Offer slight resistance to air flow. Variable Temperature Sections . Variable Temperature Heating Section. Allow close control of the delivered air tem perature without dagger of freezing which is likely when control is accomplished by throttling of steam. Invaluable in supplying fresh air for space heating or in process work. Bulletin HS-l. Detail of Wing Featherfin Heating Element thawing Compression Union Tube Connection Wing Garage Heaters For effective and economical heating of garages. Sometimes cut heating costs in half. Bulletin G-l. Wing Door Heaters For instantaneously heating inrush of cold air at large doorways of industrial buildings. Bulletin D-l. 890 L. J. Wing Mfg. Co. Air System Equipment % Fans and Blowers Wing Utility Heaters A lightweight sus pended unit heater for delivering heated air in one general direction. Has the same powerful fan and rugged heating element as WING Featherweight Unit Heaters. This is the latest refinement of the ^ original horizontal lightfreight heater which was developed by WING. Bulletin U-4C. Wing Industrial Fog Eliminators Eliminate fog, odor and fumes in dyeing, bleaching and finish ing plants, creamer ies, pasteurizing, bot tling, canning and packing plants, chem ical works, paper mills, steel pickling plants, etc. No ducts are required. Bulletin FE-12. Wing Featherfin Process Heating Units For man ufactur ing pro cesses such as drying, aging, etc., re quiring the recirculation of the heated air. Motor or turbine located outside air cur rent. Bulletin P-2. Wing-Scruplex Safety Ventilating Fans A propeller type fan that will deliver air against static pressure, quietly and efficiently. Moves the air for ward ini straight lines with minimum eddy. Capacities to 100,000 cfm. Bul letin F-7. Wing-Scruplex Exhausters For economically moving air wherever ducts are used. It combines the efficient WINGScruplex Propeller Fan with a housing which places the motor entirely outside the air duct. Motor and drive remain cool and clean and are easily accessible. The powerful WING-Scruplex Fan delivers high air volume with low power consumption against any pressures for which duct systems should be designed. V-belt or direct drive. Light, compact and easy to install. Bulletin 78-A. Wing System of Controlled Combustion For low-pressure heating boilers. In creases capacity and permits use of lowestcost fuel. Eliminates necessity of frequent firing, allowing inter vals as great as 24 hours in some cases in zero weather. Bulletin M-76. Wing Turbine-Driven Blowers Applied to hand, stoker, oil or pulverized fuel fired boilers, increase boiler capacity, maintain constant steam pressure and permit com plete combus tion of low-cost fuels. The ex haust steam, free from oil, can be used for heating or pro cesses. Bulletin T-97A. Wing Type COM Blowers (High Static Pressures at Low Speeds) Applied to high pressure boilers, produce high static pres sures at low speed. Equipped with constant-speed motor and built-in damper, permitting variation of air delivery over a wide range with decreasing horsepower. Ideal for many ventilation applications. Bulletin COS. 891 Air System Equipment Motors GENERAL. ELECTRIC COMPANY SCHENECTADY, N. Y. aT.ra OFFICES. WAREHOUSES. SERVICE SHOPS mj DISTRIBUTORS in PRINCIPAL CITIE8 For Code Wire, Conduit Products, Wiring Devices, Insulating Materials, etc.. Address--APPLIANCE AND MERCHANDISE DEPARTMENT, BRIDGEPORT, CONN. HEATING, VENTILATING, AND AIR-CONDITIONING MOTORS Wound-rotor quiet-operating induction motor on sound-isolating base. Type MB Capacitor fractionai-korsepower motor. Type KC The complete line of motors manufactured by the General Electric Company offers you a motor with electrical and mechanical characteristics best adapted to your com pressor, fan, or pump application. The most frequently used applications are listed below. Complete information on other types of motors, vertical, enclosed, etc., with various electrical and mechanical modifications, may be obtained from qur nearest sales office. A complete line of motors, designed and tested especially for quiet operation for use in schools, hospitals, commercial buildings, and also a complete line of special soundisolating bases for these motors are available when using V-belt drive. Application SOME G-E MOTORS AND THEIR USES Speed Type Winding Type Horsepower Range Classification Fans and Centrifugal Pumps Reciprocating Pumps and Compressors Constant or Adjustable Shunt Compound BA CD Bit CD 1/8-200 1 /8-20Q_____ Direct Current Small Direct Connected Fans ' Resistance Split Phase Reactance Split Phase KH KX 1/40-1/3 1/6--1/3 Belted Fans. Centrifugal Pumps Constant or 3-Speed Low Torque Capacitor Constant or * 2-Speed High Torque KC 1/50-10 KC 1/4-10 Single Phase Alternating Current Capacitor KC 1/8-10 Pumps. Compressors. Fans Repulsion Induction Squirrel Cage Constant or _ Multispeed ' (Low Starting Current) SCR K or KB KF 1/8-10 1/4-1000 71/2-75 Reciprocating Pumps and Compressors (High Starting Torque) KG 3-100 Polyphase Alternating Current Pumps. Compressors. Constant or Adjustable Constant Wound Rotor - Synchronous M & MB TS '4-1000 23-2000 This Company will gladly assist in the solution of any electrical problems in relation to heating and ventilation 892 Air System Equipment controls GENERAL ELECTRIC COMPANY . SCHENECTADY, N. Y. SALES OFFICES, WAREHOUSES, SERVICE SHOPS and DISTRIBUTORS in PRINCIPAL CITIES For Code Wire, Conduit Products, Wiring Devices, Insulating Materials, etc.. Address--APPLIANCE AND MERCHANDISE DEPARTMENT, BRIDGEPORT. CONN. CONTROL FOR HEATING, VENTILATING, AND AIR-CONDITIONING MOTORS The General Electric line of standard control offers manual or automatic equipment for com pressors, fans, or pumps driven by any type motor which you require, providing full protection for your motor, especially those listed on the pre ceding page. For special applications General Electric con trollers can be designed to meet your exact requirements. The following is a list of typical control equip ment applicable to all motors listed on the preceding page: Full-voltage automatic starters for thermostatic control of fans, or pumps. Automatic reduced- or full-voltage starters for synchronous motors driving compressors. Manual or automatic speed-regulating controllers for wound-rotor motors driving fans. Manual full-voltage starters for pump motors. Manual speed-regulating switches for small capacitor motors driving fans. ACCESSORIES Indicating Push buttons. CR7006--full voltage mag- netic switch for use with induction motors CR1061 fractional-horsepower- motor starting switch for wall mounting CR7764 Speed regulating controller for wound rotor motor (cover removed) Motors and control of one manufacture insure perfect operation, simplify installation and insure good service for the entire installation. . - This Company will gladly assist in the solution of any electrical problem In relation to heating and ventilation See also pages 816 and 817 893 Air System Equipment Motors Wagner Electric Corporation 6400 Plymouth Avenue, Saint Louis, Mo., U. S. A. Wagner motors are built in a wide range of mechanical and electrical types to meet the varied requirements of the air-con ditioning industry. These motors are care fully designed and skillfully constructed to make them quiet in operation and com pletely reliable. WAGNER POLYPHASE MOTORS Single-Speed Squirrel-Cage Motors Fynn-Weichsel (Synchronous) Motors Normal startingtorque--normal starting-current for driving radial com pressors, fans and blowers. High start ing-torque-rlow starting-current for driving recipro cating. compressors. 2 and 3 phase; Ho to 400 hp- Multi-Speed Squirrel-Cage Motors To use where sever al constant speeds reduce operating costs. Can be fur nished with normal starting-torque or high startingtorque, with two, three or four speeds. Variable torque characteristics for fan service, constant torque characteristics for compressor service. 3 phase; H to 125 hp. Wagner Fynn-Weichsel motors are leadingpowerfactor motors, having high start ing-torque, low starting-current, high pull-in torque, constant speed at all loads, and ability to carry heavy inter mittent overloads. Especially desirable where power-factor improvement or con stant speed is required. 2 or 3 phase; 7H to 200 hp. Special Compressor Motors 40 to 150 hp. The Wagner RT motor was specially developed, to meet the demand for a motor with high start ing-torque and very low starting-cur rent. 2 and 3 phase; WAGNER SINGLE-PHASE MOTORS----- ---- Repulsion-Start-Induction Motors Capacitor Motors Brush-lifting (as sures quiet oper ation, long brush and commutator life). For highstarting-torque heavy-duty appli cations. Open, totally-enclosed, and drip-proof; rigid or resilient-mounted. Ho to 15 hp. Split-Phase Motors Long-life switch and unbreakable steel frames. Open, drip-proof and total ly-enclosed; rigid or resilientmounted. Ho to H hp. Condenser-start con denser-run, Ho to 1 hp; single or multi-speedi Condenser-start in duction-run, H to H hp; drip-proof or totally-en closed end-plates; rigid or resilient-mounted. . Shaded-Pole Fan Motors Single-phase induction of simple construction re quiring no complicated starting equipment, ideally adapted to fan and blower, drives in which the fans are mounted directly on. the motor shaft. Totally-enclosed and open type, rigid base or round frame, with or without 3-speed regulator. Hso, H25, Ho, Ho, and Ho hp ratings. 894 Air System Equipment Anemostat Corporation of America 10 East 39th Street, New York City, N. Y. THE ANEMOSTAT HIGH VELOCITY AIR DIFFUSER The Anemostat High Velocity Air Diffuser is a ceiling outlet consisting of a series of circu lar diverging metal cones opening outward from a central circular neck which may be attached directly to the main or branch duct. The Anemostat assures draftless distri bution of air at any duct velocity.. Various standard sizes from 2 in. to 38. in. neck diame ter will distribute volumes of air between 10 cfm and 25,000 cfm and will handle any velocities between 300 fpm and 4000 fpm. When introducing large quantities of air into a room air motion results. The series of cones which form the Anemostat discharge the air in definite proportions in all directions in a series of planes. This diffusion together with the as piration (suction) effect causes prompt equal ization of temperature and therefore, humidity throughout the room, horizontally, and defi nitely prevents air pockets and dissipates the evaporation aura around the human body. The air-mixing effect of the Anemostat causes the predetermined room temperature to be established at a point well above the breathing level, which permits the use of higher temperature differentials. This in turn, results in smaller volumes of air to be conditioned and therefore in smaller plants, reduced operating expenses and smaller ducts, while the high velocities which may be employed because of the draftless diffusion, result in further reduction of duct sizes and simplifica tion of duct layouts. At the different velocities recommended for rooms used for different purposes the increase in decibel ratings through the use of Anemostats is negligible. The Anemo-lite which is an Anemostat combined with a built in lighting unit is an ideal solution to the combined problem of Air Distribution and Lighting. (See Figure 1). Pendent lighting fixtures may be hung directly from the center cone of the Anemostat if desired. (See Figure 2). Particularly suitable for theatres and auditoriums is the Anemostat combined with the indirect lighting unit. (See Figure 3). With this combination unusual and effective results are easily obtained. Complete technical information on the Anemostat combined with lighting fixtures is available upon request. > I Fig. S Fig. 1 Fig. S "No Air Conditioning System is better than its Air Distribution'* 895 Air System Equipment orfi/el"'5 The Auer Register Co. 3608 Payne Avenue, Cleveland, Ohio Manufacturers of Registers and Grilles for Gravity and Air Conditioning Systems; Wrought Metal Grilles for Concealing and Protecting Radiation AIR CONDITIONING REGISTERS AND GRILLES The Auer line of registers and grilles for heating and air conditioning systems is modern and complete, offering a wide choice of styles for every purpose. Only a few representative models are shown on this page. ' Fin-Flex No. 5030 Register with Band Iron Frame Flexible fins % in. on center offer satisfactory one time adjustment. Adjusting tool furnished with every order. Horizontal fins, furnished as standard. Ver tical fins furnished if specified. Same design furnished also without valve, as a return. Fin-Flex Registers and Grilles are made with either vertical or horizontal fins which are easily adjusted at time of installation for single or multiple air current in any direction. Ample free air capacity for modern forced air systems. Dura-Flex Register and Grilles are also furnished with blades adjustable for any desired air flow. Other Dura-Flex designs are available with fixed blades. DuraBilt Floor Registers and Cold Air Faces are assembled with steel cross-bar construction, all cross joints locked and mortised. These should be specified whereever extra strength is required. They come in medium or narrow mesh. The Auer Classic face has wide popu larity for air conditioning and heating uses. 11 is an unusually attractive face, appropri ate to most interior decorative schemes. Fin-Flex No. 9030 Register with Band Iron Frame Horizontal Fin-Flex for upward and downward deflection is standard. Vertical Fin-Flex for twoway side deflection also furnished. Same design furnished also without valve, as a return. All Auer models are designed with due regard for air capacity, and supplied in all required sizes and finishes. Complete Catalog 39, showing all types for air con ditioning and gravity heating, furnished on request. . Dura-FJex No. 8132 Register--No Frame Adjustable bars Yi in. on center. Also furnished with horizontal bars (adjustable). Small, convenient adjusting tool furnished with each order. Some design furnished also without valves, as a return. 896 Classic No. 2030 Register (with Valve) Band Frame ' Air System Equipment f/,"'ers Barber-Colman Company Rockford, Illinois , ENGINEERED AIR DISTRIBUTION OUTLETS ' Venturi-Flo Venturi-Flo is a ceiling type outlet of modern design which mixes conditioned air and room air and distri butes it over the desired area. The units are made in flush and surface types and in sizes to permit handling volumes of air from 6 cfm to 15,000 cfm. Comparatively high velocities may be used without increasing the noise level or causing objectional drafts Units are available in standard finishes. Either type may be obtained with adjustable dampers or in com bination with lighting fixtures. Uni-Flo Uni-Flo grilles and registers are designed and pre fabricated with directional flow aspirating fins especially for air conditioning installations. Therefore Uni-Flo grilles and registers assure proper air distribution and obviate the necessity of adjustment at the installation. Dimensions and core arrangement may be selected to give desired directional flow and throw without in creasing the noise level or causing drafts. Various sizes and shapes are available including curved surfaces. Registers are similar in construction to grilles, but with the addition of spring loaded, positive dosing, chain or key-operated dampers. Electroplated Finishes: Gunmental, brushed bronze, plain zinc, buffed zinc, and satin copper. Also available in plain metal, gray prime coat, or clear lacquer. Veniuri-Flo--Flush Type Venturi-Flo--Surface Type Uni-Flo Grille Uni-Flo Register Uni-Fin Uni-Fin grilles and registers are designed especially for residential warm air installations. Available in standard sizes and prime coat or electroplated finishes. Unt-Fin Register THE CORRECT TYPE OF OUTLET FOR EVERY REQUIREMENT (Sec also Page 913) 897 Air System Equipment a'rfuJfTM Hart & Cooley Manufacturing Co. Established 1901 . Air Conditioning Registers and Grilles - Warm Air Registers Damper Regulators - Furnace Regulators - Pulleys - Chain Holland, Mich. No. 86 DESIGN REGISTER WITH TURNING BLADE VALVE ADJUSTABLE DOUBLE DEFLECTION Available in Two Types: ( Instant Adjustment of Air Flow (Up, Straight or Down) Is obtained by turning the regulator on the register face to the proper setting with a key furnished with each register. When the valve is opened, as shown at the left, the individual valve louvres automatically stop in position to provide the proper air flow--Up (Fig. 1) for cooling systems to avoid drafts; Straight (Fig. 2) for ventilating systems; Down (Fig. 3) for heating systems to prevent stratification. When the valve is closed, as shown at the left below, it completely stops the flow of air. Air Flow Can be Quickly Adjusted Sideways The air flow is controlled sideways by the vertical bars in. deep on % in. centers) which may be turned 45 deg to either side with the same key used for turning the regu lator. The register face is divided into two sections by an attractive vertical mullion. The bars in each section are connected with each other, so that by turning one bar in a section, all the bars in that section turn simultaneously, making it a simple matter to obtain practically any sideways deflection of the air. Greatly Reduced Turbulence and Resistance Figs. 1, 2, and 3 show the air flow with No. 86 Design; Fig. 4, with the conventional register. Compare the turbu lence in the stackhead of the latter with the smooth flow obtained with No. 86 Design. So efficient is No. 86 Design that there is actually less resistance with this register, using a standard stackhead, than if no register at all were used. Fiz-1 Fig, Fig. 3 Fig. 4 , 898 Haft & Cooley Manufacturing Co. Air System Equipment a%`fjfrs Velocities -with No. 86 Design - Velocities with Conventional Register EVEN DISTRIBUTION OF AIR OVER ENTIRE FACE The turning blade valve on No. 86 Design distributes the air evenly with a uniform velocity over the entire face, as shown in Figs. 1, 2, and 3 on the preceding page. Note how the air rushes through the upper part of the face with a conventional register, as shown in Fig. 4. Since the entire face of No. 86 Design register is utilized for discharge of air, smaller and in some cases fewer registers can be used without causing excessive velocities. ' Prevention of Streaked Ceilings---With either UP, STRAIGHT, OR DOWN deflections the air does not strike the ceiling immediately in front of the register; streaked ceilings are thus avoided. Excellent Concealment of Duct--The depth and close spacing of the vertical bars, combined with the valve, provide almost complete concealment of the duct, adding considerably to the pleasing appearance of the register face. Special Settings--No. 86 Design functions equally well when located at the end'of a horizontal duct or. by installing it upside down, when the air is delivered to it from above. Four Types of Installation Frames Available Nos. 861 and 864 Registers may be used with or without installation frames. The following four types of frames are available: . No. 2 Band Iron Frame-^A simple inexpensive frame for sidewall or baseboard use, in old or new house installations. 9 No. 3 Sidewall Stud Frame (illustrated)---The ideal sidewall frame for new house installations. No blocking-in required. Frame provides permanent solid foundation for register and stackhead and eliminates possibility of streaking. No. 5 Baseboard Stack Frame--Easy to install on old or new house work. Stackhead is held securely in place. No. 8 Baseboard Stud Frame--Similar to No. 3 Sidewall Frame, except has greater depth to compensate for thickness of baseboard. Ideal for new house installations. Catalog No. 39 AC Available on Request . . , This catalog contains a very useful 10-page section of technical data and shows the complete line of H & C Air Conditioning Grilles and Registers. . 899 Air System Equipment Ge,fuJsBra Hendrick Manufacturing Company Hendrick Perforated Metal Grilles 48 Dundaff Street, Carbondale, Pa. Sales Offices in Principal Cities--Consult Telephone Directory , PRODUCTS--Hendrick Perforated Metal Grilles; also Mitco Open Steel Floor ing, Mitco Armorgrids and Mitco Shur-Site Treads. Hendrick Perforated Metal Grilles The Hendrick line of perforated metal grilles is a large and varied one, offering the architect, contractor, building owner, etc., literally hundreds of designs from which to select the grille or grilles best adapted to specific installations. In ad dition to standard patterns, Hendrick offers a number of exclusive grille designs, many of them being covered by design patents. All Hendrick Grilles are characterized by clean-out perforations and fine finish. They are given a special flattening oper ation which makes for easy installation. Hendrick Perforated Grilles are fur nished in aluminum, brass, bronze, copper, Everdur, Monel, nickel-silver, stainless steel, steel, zinc and other commercially rolled metals. They are supplied un painted, or with prime coat; with lacquer or duco finish in any color; with natural polish or with any standard electroplate finish. Furnished from 16 gage to \6 in. thick, up to 90 in. wide and almost any length. They come with invisible access doors, angle frames, hinges, etc. Hendrick Fixed Louvre Grille; ideal for doors in hospitals, hotels, bathrooms. Permits free circulation of air but prevents vision through the grille from any angle. Easily installed in any door. Regularly furnished in No. 18 U. S. Gage Steel. Can be furnished in aluminum, bronze, or 0.05 in. thick stainless steel. Nozzle Grille For air conditioning systems utilizing high velocities; most efficient in minimizing the noise of air passing through a grille opening. Hendrick Nozz'.e Grille is generally furnished with % inch diameter perfora tions but can be had in a large variety of sizes, in alu minum. bronze, stainless steel, and steel, in gauges up to .078 in. thick and in sizes up to 48 in. by 180 in. JM1I \m ij&i! ijsli 1 iifrSii ii&ffii lif>Sil iiftftf iiMii Iiftfit iifitfi i".."i ifT. ,T La Crosse Design Patent No. 89,684 Write on your letterhead for a copy of 194-page handbook, "Hendrick Grilles." 900 Air System Equipment cf/isers The Independent Register Co. Established 1898 3747 East 93rd Street, Cleveland, Ohio INDEPENDENT "Fabrikated" ; \ Reg. U. S. Pat. Office AIR CONDITIONING REGISTERS AND GRILLES No. 311-A--ADJUSTABLE DIRECTED AIR FLOW ' With Horizontal Grille Bars With "Independent" Adjustable Directed Air Flow Registers and Grilles the Engineer is in com plete control of the direction of air flow. The directional adjustment can be made at the time of installation--or after the system is operating, to meet unforseen or changed con No. 5//--%--Air Flow Downward Adjustable from straight to 45 deg. ditions. The method of adjustment is simple as shown, and many directions Patented and combinations can be developed to suit the need! Each interior No. 321-A--ADJUSTABLE DIRECTED AIR FLOW grille bar is ad justed individ With Vertical Grille Bars ually. Standard registers are furnished with single valves;--they are also made with "Multiple Valves" operating in unison--also with rear "Deflecting Vanes" which can be adjusted individually--with which the Engineer is given a dual control of the air flow--being able to secure right and left together with up and down deflection at the same time. Patented Grille Bars set for straight, right and left deflection. The grille bars are set in a firm tension, yet easily adjusted, with the tool sent with each order. /jt/u'iijnlnilifiiiffi ii nil 11 i(i 111 aL No. SS1-A--Showing a combination of Adjustments Ceiling Outlets are furnished in several sizes--both Round and Square styles. Ceiling Outlet No. 1860-R Ceiling Outlets offer one of the most flexible units for ventilation and distribution of cooled or heated air. The ceiling outlet grilles are of perforated metal. We manufacture many other types and styles of Registers and Grilles; a complete line. No. 811-A--:Knob Control The Nos. 311-A or 321-A Regis ters can be furnished with either Lever, Knob, Key, Chain or Pull Rod Control. You should have the Independent Register Catalogues--Yours for the Asking. 901 Air System Equipment SS'rs Tuttle. & Bailey, Inc. New Britain, Conn. Branch Offices': Boston. New York. Chicago. Philadelphia Air Conditioning Grilles, Registers and Intakes Air Control Devices Ornamental Grilles Cast or Wrought Metals AtROFDst()ouTLET A Truly Flush Type Ceiling Diffuser A new ceiling diffuser, perfected after months of research. Because of the unique design the supply air is brought into contact with room air over the largest possible area immediately after leaving the outlet. This results in a high rate of temperature equalization and eliminates the possibility of drafts. The Aerofuse Outlet is practically flush with the ceiling which permits its use with any type of interior decoration. 1 Efficient Air Mixture ... 2 Rapid Temperature Equalization ... 3 Complete Air Distribution . . . 4 Total Elimination of Drafts ADJUSTIBLADE REGISTER WITH FLEXAIR FACE A new register of utmost flexibility for scien tific air distribution. Instantly adjustable for upward, downward or horizontal deflection of air stream. Uniform velocity and even air distribution.over entire register face. Negli gible. resistance to air flow. Furnished .with Flexair (face (adjustable deflection of face bars). For complete information on Tuttle & Bailey's entire line of Air Conditioning prod ucts, write for copy of latest catalog No. 40. Instantly Adjustable for Upward, Downward, or Horizontal Deflection of the Air Stream 902 Air System Equipment oerfnJsrs Tuttle & Bailey, Inc. New Britain, Conn. uimmasiiiiiiimiiiiiiiiiimmmiiM 1 KHiiBinissniiiiimiiiiiiiiiiiimmim THE AIRLINE GRILLE Provides fixed air deflection. Very moder ately priced. Vertical or horizontal bars. Also furnished with series of individually operated blades directly behind face of grille which run in opposite directions from face bars and so provide for a combination of vertical and horizontal deflection. THE FLEXAIR GRILLE Solid bar construction. Provides adjust able air deflection. Vertical or horizontal bars. Also provided with individually operated blades for combination vertical and horizontal deflection. SANTROLS A device which provides positive control of air volume throughout an entire duct system, and insures even distribution of air over each outlet face. An inexpensive unit that accomplishes much. Ducturns are composed of scientifically designed turning blades. . They eliminate the necessity for long radius turns and allow the use of right angle elbows. Duc turns greatly simplify the layout of duct work and furnish a much more attractive and finished installation. REMOTE CONTROL Ideal for hotels, office build ings, large public buildings. Makes possible individual control of air volume by the mere turning of a knob in McKNIGHT REGISTERS 0 every .room throughout the A scientifically designed register for com building. A real advance in mercial air conditioning work. Provides air conditioning for com positive control of air volume at the outlet. mercial buildings, yet com Volume control louvers are operated by paratively inexpensive to means of a special key furnished with 0 install. each register. Air System Equipment crf/ta?"' United States Register Company General Offices: Battle Creek, Mich., U.S. A. Branches: Minneapolis, Minn., Kansas City. Mo.. Albany, N. Y., New York, N. Y., San Francisco. Calif. Air Conditioning Registers, Vents and Grilles CANADA REGISTER & GRILLE CO.. Ltd.. Toronto. Ontario Manufacturing Distributors of U. S. Registers; Grilles, Etc. Style 16$ fi 9 Style 153--Louver-Type Air Con ditioning Register--Bars % in. deep-- Spaced 4 openings to the inch affords Non-Vision. Can be supplied in Di rectional Flow in either Horizontal or Vertical Bar Styles. Can be furnished with all Styles or Setting Frames and with INSET PANELS which con veniently afford Multi-Flow. . Style 249-LF--Duo-Deflection Air Conditioning Register. Gives com plete Air Control. Vertical front bars --Key-pin adjusted to provide 45 deg Right and Left or Two-way Flow. Lever operated Horizontal Back-valves give from Full Closed to any degree of Up-flow and to 45 deg Down-flow. FULL FACE COVERAGE. Can be supplied with any style frame. Fits all Stack Heads. Stvie 11(5 Style S49LF Style 145--U. S. Adjustable-Bar Air Conditioning Register. Horizontal bars adjust from 60 deg Up-flow to 60 deg Down-flow, by Key-pin which is re movable. Does not MAR or INJURE the Register finish. Can be furnished with any style frame or with INSET PANELS which provide Right and Left Multi-flow. All of above Styles can be supplied with either Lever or Individually adjusted Multiple Valves or Lou vers. I.E. 153VVI--Vertical Valves Individually adjusted. 145VVL Lever operated Vertical Valves. Style 103--Vertical Lattice Per forated Register for Forced Air Sys tems--Not directional flow. Style 102 -- Vertical Embossed Bar Design--Not directional flow. Grilles and Vents in Matching designs. ^ Styles lOB-lOS For Complete Information Write for Catalog 27--Third Edition. 904 Air System Equipment Waterloo Register Company Waterloo, Iowa Established 1902 Seattle, Wash. *. Representatives in Principal Cities FG-75 GRILLE FGV-75 Front blades parallel to short dimension. FGH-75 Front blades parallel to long dimension. Individually adjustable double di rectional grille with streamlime blades 1 in. deep spaced on % in. centers. A removable wrench pro vides adjustment after installation. Depth of grille in. TECHNI-TROL VOLUME DAMPER Made to fit inside dimensions of duct. The blades of this damper are arranged to open and close on rust proof bearings so that the volume of air may be reduced or increased without deflecting the air stream from a straight course. Can be arranged with locking mechanism for operation through grille or can be attached to various remote con trol wires or rods. MULTI-PLAK Adjustable square ceiling outlet. Because of its streamline design this unit provides the adaptability of the square ceiling outlet without the plain "box" appearance. Each outlet consists of four streamline four-way adjustable grilles, each one capable of being entirely closed. May be furnished with or without light fixture. Made of steel only, in any standard grille finish. Available without light fixture in 6, 8, 10, 12,14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36 inch square duct opening sizes. Available with light fixture in 6, 8, 10, 12, 14, 16, 18, 20, 22 inch square duct opening sizes. Write main office for complete catalog and descriptive matter. 905 Air System Equipment Registers Grilles Wickwire Spencer Steel Company 500 Fifth Avenue, New York City . Buffalo Chattanooca Chicago Los Angeles Worcester Seattle Detroit San Francisco Philadelphia Portland Agents in Principal Cities WISSCO STAMPED GRILLES and PERFORATED METALS rjirjirjir.i Annwli rjirnrjirji AAuuu The Wickwire Spencer Steel Company was the first perforator in America to produce .stamped metal grilles. Over fifty years* experience in this field, modern equip ment, complete warehouse stock, and competent workmen having an average service record of over seventeen years, assures excellent service and a superior product. Design 820 Wickwire Spencer's modern machinery produces grilles as heavy as inches in thickness, and in any size or shape up. to 60 inches x 156 inphes-in-one piece. Larger sizes in two or more pieces suitably joined so that the joint is virtually invisible on the front of the grille. All .tools, both for standard design grilles and those of special design, are supplied by our own tool room. ' . . . Design 860 Wissco Grilles are manufactured in over 100 different styles from standard dies, and in many special designs and curved shapes' to customer specifications. Per forations are designed so that uninterrupted vertical and horizontal members give Adequate rigidity and strength of grille structure with effective concealment and free air openings as high as 70 per cent of grille area. lllslllElllEIIIslIlElilsIll =iu=mam=iu=ii8=iii= l=!ilslll=IIIEHIE!ll=IJI SfilEIIIEItlsIHEHISillE ; IIIEIIIEUIEI1I=I!IEII1EU! =MEIIlEIUSIIISniElll= Wissco Grilles are fabricated from steel, bronze, - brass, aluminum, stainless steel or monel. Any standard electroplated finish can be supplied on steel. Polished, or oxidized standard*finishes can be given bronze, and polished or alumilited finishes can be applied to alumi num. Special finishes to. match adjoining metal or to harmonize with the surroundings can also be furnished. Invisible doors, hinged grilles, angle frames, or.other special features will be supplied as required. Other ^sheet metal designs and specialities produced as desired. Design 204 Our new catalog "Wissco Grilles" gives detailed analysis and specifications of grilles layouts. A copy will be mailed to you upon request. . 906 The American Rolling Mill Company ^ Executive Offices,- Middletown, Ohio . Atlanta Ga., ` *' . 1437 Citizens and Southern National Bank Bldg. - "Vi Boston, Mass.____________ ____ ____ 201 Devonshire St ; V-sBottalo, N: Y........... -......-504 Seventeen Court St Bldg. - ^Chattanooga, Tenn............ 712 Chattanooga Bank Bldg. 'Chicago, III.-.:............ ........... --310 8. Michigan BHg. Cleveland, Ohio--......--............ -.1516 B. F. Keith Bldg. Dallas, Texas------ ---------------- -------1111 Santa Fe Bldg. Detroit, Mich................... _....5-261 General Motors Bldg. Indianapolis. Ind.-'............. -........................... Circle Tower Kansas Ghr; --:.......................... 7100 Roberta St. Looibvtlle, Kr...... .................. ............ ;2608 Landor Avc. Middletown, Ohio:__703 Curtis St Minneapolis, Minn____ _,, 171-27th Ave. S E New Orleans, La.3501 S. Carrol]ton Ave.* New York, N. Y,,__________________ i?n Broadway Philadelphia, Pa1808 Lincoln-Liberty Bldg. Pittsburgh, Pa_____ ___________ 1632 Oliver Bldg. San Francisco, Caup______ _____________ .46S Tenth 8t Sr. Louis, Mo.-'--____________1725 Ambassador Bldg. Choose the Correct Armco Grade These grades of Armco sheet metal are recommended for the air conditioning applications shown. For detailed information get in touch with the nearest district office or write direct to The American Rolling Mill Company, Middletown, Ohio. Armco Ingot Iron ' (Galvanized) ' , Ducts Washer Chambers Plenum Chambers Steam Line Casings Furnace Casings Spray Towers Drip Pans Housings , Machine Guards Unit Conditioners ' ' (Industrial) - Roof Ventilators .. Eliminator Blades - Armco Paintgrip (Galvanized) Recommended for all applications listed above that need immediate painting. Send for complete information. Hot Rolled (Sheets and Strip) ' '' Fan Blades.. . Blower Casings * Fuel Oil Tanks'' . -* Unit Conditioners. ! Stoker Hqppers "" ~ ..r . #v Armco Ziticgrip A special galvanized slfeetTthat can be severely formed without peeling or flaking of the zinc coating. Cold Rolled- (Sheets and Strip) Furnace Casings Room Unit Casings ' ' Plates (ARMCO Ingot Iron) . . Smoke Stacks Coal Hoppers . Breeching : - Unfired Pressure Vessels - Low-fired Boilers "' * Tanks Armco* H. T. -50 A low alloy, high tensile st;eel possessing great strength. Used with ^proper.design it results in weight reduction of frame work, tanks and similar items. Under atmospheric^ seryice conditions it has. four to six times the resistance of regular steel. Stainless Steel . .' . (Sheets, Strip and Plate) , Combustion Chambers . ' - Heat Flues and Tubes . Furnace Casing Trim ` Grilles . 7 Corrosion Resistance Fan and Blower Blades Heat Resistance without destructive scal ing up to 1600 F. or higher. . Other Armco Products The grades for these applications are only a few that Armco makes. Others include copper-bearing sheets and plates and open-hearth steel, either galvanized or uncoated. ' 907 Air System Equipment Sheet Metal and Tubular Products Bethlehem Steel Company General Offices: Bethlehem, Pa. Bethlehem Steel Company, General Offices: Bethlehem. Pa. District Offices: Akron, Albany, Atlanta, Baltimore, Boston, Buffalo, Chicago, Cincinnati, Cleveland, Columbus, Dallas' Denver, Detroit, Honolulu, Houston, Indianapolis. Johnstown. Pa., Kansas City, Mo., Los Anceles, Louisville, Milwaukee, Nashville, New Haven, New Orleans, New York. Philadelphia, Pittsburgh, Portland, Orb., St. Louis, St. Paul, Salt Lake City, San Antonio, San Francisco', Savannah. Seattle, Springfield, Mass., Syracuse, Toledo. Tulsa. Washington. Wilkes-Barre' York. Export Distributors; Bethlehem Steel Export Corporation, New York. ' COPPER-BEARING BETH-CU-LOY FOR RUST RESISTANCE The charts at the right show conclusively the superior rust resistance- of copper bearing steel. Sheets of the same com position as Beth-Cu-Loy, Bethlehem's copper-bearing steel, outlasted ordinary iron and steel by a wide margin when exposed to atmospheric corrosion. Beth-Cu-Loy, available in the form of sheets, pipe and plates, offers 2 Co 3 times longer life as indicated by these three corrosion tests--and Beth-Cu-Loy costs only 3 to 5 per cent more than ordinary steel, much less than open-hearth or copper bearing iron. Heating, ventilating and air conditioning engineers, architects and contractors are finding it pays to specify Beth-Cu-Loy wherever moisture or corrosion is a factor. Beth-Cu-Loy sheets are easily workable, durable and low in cost. A.S.T.M. Test of 22-gage black sheets Years to average first faiture of 4 materials TP I ' /It PITTSBURG Copper-bearing Iron Copper-bearing Steel _1_ Sheets exposed April 21, 1926; tests still under wav (see Proceedings of A.S.T.M.--Committee A-5. Vol. 38). No failures in copper-bearing steel sheets at last report. BETHLEHEM MAKES: . Sheet Steel -- all grades, hot-rolled (black), cold-rolied, and galvanized-- available in Beth-Cu-Loy. ; Steel Pipe^--all sizes and weights, buttwelded and lap-welded. Ammonoduct--A new kind of pipe that has' an outstanding advantage in its unusual ductility. It can be bent cold, without need for annealing, without danger of fracturing. Recommended for ammonia piping and for heater coils, water legs in furnaces and similar uses where pipe must be bent. Boiler Tubes--Charcoal iron and steel. 24 6 8 10 12 Sheets exposed April 19. 1917; test discontinued April 16. 1928 (see Proceedings of A.S.T.M.-- Committee A-5. Vol. 28). Only 10 of 61 copper-bearing steel sheets had failed when test was discontinued. f 1 I 1 1 1 M 1 I | I i I I j l l l~ I | "Tl I | /tt ANNAPOLIS Copper-beoring Iron Copper-bearing Steel Plates--all sizes; flanged and dished heads. Available in Beth-Cu-Loy. Literature and further information on any of these products can be secured from the nearest district office or from the general offices in Bethlehem, Pa. 20 25 Sheets exposed October 17. 1916; tests still under wav (see Proceedings of A.S.T.M.--Committee A-5. Vol. 38). Onlv 9 of 78 copper-bearing steel sheets had failed at last report. A booklet "Beth-Cu-Loy Sheets," gives the story of these tests. A copy is yours for the asking. 908 Air System Equipment Sheet Metal and Tubular Products Camegie-Illinois Steel Corporation General Offices: Pittsburgh and Chicago District Offices ' CHAM K1 OeiMOO ClNONNATI Cleveland Denver Detroit Houston Indianapolis Milwaukee New York Philadelphia Pittsburgh St. Louis St. Paul Washington COLUMBIA STEEL COMPANY, San Francisco, Pacific Coast Distributors UNITED STATES STEEL PRODUCTS COMPANY. New York, Export Distributors RUST-RESISTING U S S COPPER STEEL GALVANIZED SHEETS Copper steel is an alloy made by adding copper to molten steel, thereby increasing the resistance of steel to rust. Metallurgists, railroad construction engineers and independent research laboratories have tested U*S*S Copper Steel and discovered that it lasts two {o three times as long as plain steel when subjected to atmospheric corrosion. When you specify U`S*S Copper Steel Sheets for air-conditioning ducts or equipment, you get the advantage of 100 per cent to 200 per cent longer life for about 5 per cent more cost. Duct work is so costly to replace that Copper Steel should be considered for any worthwhile job. U*S*S Copper Steel Sheets are saving thousands of dollars yearly in the ceaseless fight against rust. They give maximum protection per dollar of cost and are being used in ever-increasing volume by heating, ventilating and air-conditioning engineers, architects and contractors. Gauges of Steel Sheets Used for Duct Construction HEATING AND VENTILATING Round Ducts Rectangular Duct* Dim, Inches 6 to 19 20 to 29 30 to 39 40 to 49 SO tnd above Gauge 26 24 22 20 18 Width, Inches 4 to 18 19 to 30 31 to 60 61 to 118 118 and above Gauge 26 24 22 20 18 Ptanmg'MiU and Other Exhaust Systems . Dianu. Inches Up to 8 9 to 14 IS to 20 21 to 30 Gauge 24 22 20 18 In the above table rectangular ducts are to have cross breaks for the gauges shown, otherwise two gauges heavier should be used. One inch standing seams should be used on widths up to 48 in., in. seams on widths over 48 in., and.for widths over 60 in., the seams should in addition be provided with reinforcing bars or angles. (This material is reprinted by permission from "Fan Engineering." Buffalo Forge Co.). U*S*S Black and Galvanized Sheets Two principal types of black sheets are used by air-conditioning engineers. They are U-S-SHot Rolled and U'S-SHot Rolled Annealed. These steel sheets may be had in a number of different finishes, suitable for all sorts of forming operations and for painting. Remember that every kind of U'S'S Black Sheet is available in Copper-Steel Black Sheets for blowers, refrigerator cabinets, dust collectors, tube collectors, fans, ducts and a thousand other specialty products. ' Five types of galvanized sheets made by U'S-S Subsidiaries are used extensively in heating and ventilating work. The best types for your particular products or installa tions may be ascertained by consulting U'S-S engineers. Write the nearest branch office. 909 Air System Equipment twS Jones & Laughlin Steel Corporation AMERICAN IRON AND STEEL WORKS Jones & Laughlin Building, Pittsburgh, Pa. WELDED AND SEAMLESS STEEL TUBULAR PRODUCTS J &L Welded Pipe Ductility, strength and safety-- make this product especially adapt Jones & Laughlin manufactures able for air, steam, gas and gasoline Standard Weight, Extra Strong, and lines, boilers, refineries, dry kilns, Double Extra Strong Welded Pipe, refrigerating systems and other Black and Galvanized, for steam, exacting applications. gas, air, water, refrigeration and sprinkler work. Sizes: 14 >n- to 16 in. j & L Hot Rolled Seamless O.D. inclusive. . - Steel Boiler Tubes J & L Copper-bearing Steel Pipe, when specified, can .'be supplied in standard J & L Seamless Boiler Tubes are manu weight, or extra strong, black or gal vanized. Use of this product is recom mended for long life, where piping is to be exposed to the atmosphere or other alternate wet and dry conditions. - Jones & Laughlin Steel Pipe is made of soft, weldable steel rolled from solid ingots factured in accordance with the A.S.Af.E. Boiler Code and comply with the A.S.T.M. ' Specifications and the rule&and regulations of the Bureau of Marine Inspection and Navigation of the U. S. Department of Commerce. They are supplied in a full range of standard sizes, from 1 in. O.D. made to a special analysis. The steel pipe produced is soft and ductile, free cutting, strong at the welds, and free from excess scale. J & L Pipe is commercially straight and free from blisters, cracks or other to 6 in. O.D. inclusive. | The process by which Jones & Laughlin I manufacturers seamless boiler tubes is largely responsible for the unusually high , ductility of the product. It is a process in injurious defects. Careful attention is given the threading I which a forging action is predominant, I and produces a desirable combination of of the pipe with good clean-cut threads fitted with sound couplings correctly tap I strength with a highly ductile nature, i J & L tubes therefore are installed with ped to give a tight joint. Soft, ductile steel ease and safety. of free cutting quality enables the con tractor to cut clean, sound threads on the job. The Jones & Laughlin process of gal vanizing assures a thorough coating and insures against pipe being clogged with spelter. The galvanized coating adheres strongly and does not tend to flake off. Other J & L Tubular Products J & L also manufacturers Reamed and Drifted Pipe in sizes 1 in. to 6 in. inclusive, Dry Kiln Pipe, Pipe for Refrigeration Service, Water Well and Irrigation Casing, Line Pipe and a complete line of Oil. Country Tubular Products in'welded and seamless. * . < J & L Seamless Pipe Also J & L Flat Galvanized Sheets for J & L Seamless Pipe is made in three weights; standard, extra strong and double extra strong. Sizes: }4 in. nominal to 14 in. O.D. inclusive. J & L Seamless Steel Pipe is pierced from a solid billet--there are no welds. The result is dependable aiid uniform wall strength. The method of manufacture, and the use of only specially selected steel, assure exceptional ductility, a quality that is essential to successful coiling and bend ing, and flanging for Van Stone joints. J & L Seamless Pipe can be used with full satisfaction in either threaded joint or completely welded installations. . Air Conditioning arid Ventilating Work Pipes, ducts, stacks and trunk lines made of J & L Flat Galvanized Sheets give a lasting, neat looking job. These sheets have a tight galvanized coating that will not spall or flake off during forming operations. J & L Flat Galvanized Sheets provide uniform resistance to corrosion. The superior quality of J & L Galvanized Sheet Products is assured in every,ship ment, because J & L*s 96-inch Continuous Strip Mill, where J & L Galvanized Sheets are rolled under rigid control, is one of the most modern in the world. 910 / CONTROLS AND INSTRUMENTS ' Automatic controls form an essential part of modern heating, ventilating and air conditioning equipment, and for the refrigerating equipment which performs important functions in many air conditioning operations. Their use makes possible accurate maintenance of desired physical conditions, with an operating efficiency and economy which are not obtainable with manually operated controls. 'instruments of many types and for many uses are available for determining the capacity and operating efficiency of apparatus. These instruments are designed-to obtain results in conformity with adopted test methods and operating standards. . CONTROLS (p. 912-937) . Thermostats--room, immersion, insertion and surface types; humidity* controls, pressure controllers, damper motors, control valyes, solenoid valves, relays, etc. . For control of air, gases, temperatures, humidity and liquids;, for automatic fuel burning apparatus; for all types of heating, ventilating and air conditioning apparatus operating as separate units, or as integral parts of central systems. The various types of automatic controls include electric, pnuematic, and selfcontained control systems--two-position, or on-and-off, and the modulating or graduated control. They are adaptable for individual room control, or for zone control in Urge buildings, and also for industrial process control. Technical data on automatic controls will be found in Chapter 38. INSTRUMENTS (p. 912-937) For measuring, indicating and recording air velocity, temperature, humidity, pressure, flow and liquid levels; arid for testing and rating heating, ventilating and air con ditioning equipment. They include gauges, meters, recorders and indicators, hygrometers, pyrometers, psychrometers, thermometers, velometers. Technical data on instruments is contained in Chapter 45. Manufacturer's products shown In this division are designed for specific applications. Consult the Index to Modern Equipment for additional products of these manufacturers. 911 Controls and Instruments 41 LB Alco Valve Company ENGINEERED REFRIGERANT CONTROLS 2638 Big Bend Blvd., St. Louis, Mo. New York Office: 381 Fourth Ave. Chicago Office: 433 East Erie St. A complete line of Engineered Refrigerant Controls THERMO EXPANSION VALVES For automatic control of liquid refrigerant on all types of air conditioning and refrigeration systems. Type TK .. .. . Type TJL Type THL CAPACITIES--From fractional tonnage to 100 tons Methyl Chloride, 50 tons Freon-12. MAGNETIC STOP VALVES For all types of service Magnetic Liquid Stop Valves Freon--up to 75 tons Methyl Chloride--up to 150 tons. Magnetic Suction Stop Valves Freon*--up to 1H" or 8.8 tons Methyl Chloride--up to 1 l/i' or 17 tons. ,,, Type St Type MS Type RS AMMONIA1 CONTROLS Magnetic Liquid Stop Valves -- up to 172 tons. Magnetic Suction Stop Valves-- up to 1W or 28 tons. Thermo Expansion Valves-- from fractional tonnage to 60 tons. Type M.6 ALCO also offers Magnetic Stop Valves for brine, water, gas, air and steam; specially designed Magnetic Compressor Discharge Valves and Magnetic Pilot Check Suction Stop Valves (for lines subject to reverse Flow). In addition, the Alco line of Engi neered Refrigerant Controls includes Float Valves, Float Switches, High Pressure Float Valves, Constant Pressure Ex pansion Valves and liquid and suction line Filters. 912 I i, !i Controls and Instruments Barber-Colman Company Rockford, Illinois TEMPERATURE and HUMIDITY CONTROL EQUIPMENT Barber-Colman Controls are all electric. Precision built to insure long, continuous, and dependable service. Easy to install in either new or existing installations. Ready fAr instant service at all times, even after long shut down periods. Thermostats, Hygrostats, and Comfortstats. Instruments for controlling dry-bulb, wet-bulb, effective temperature, and relative humidity. For snap-action, floating, or pro portioning control. Supertherm has a hori zontal bimetal element and is more sensitive to changes in room temperature. The Comfortstat takes into consideration relative hu midity as well as temperature and' therefore regulates in accordance with effective tem peratures. The Econostat (not illustrated) is a com plete self-contained thermostatic unit for the automatic regulation of the heat supply of a building in accordance with outdoor tem peratures. Motor-Operated Valves. Packless, packed, single seat, pilot piston, veeported, balanced, three-way, four-way, and butterfly. For shut-off, throttling or proportioning service. Also solenoid valves for air, oil, water, gas, and refrigerants. Motor-Operated Valves are powered with Barcol motors which have only one moving part and require no attention except oiling; oil submerged operators require no attention. All gears are machine cut and steel gears heat treated. All exposed steel parts are zinc plated. Motor-operators are detachable as units. (See also Page 897) 913 Damper Control Motors. Unidirectional or reversible, fixed or adjustable speed. For positive or proportioning Op eration of dampers in heating, ventilating, air conditioning, or industrial applications. Oil-submerged models have the motor and gear train entirely submerged in oil, thus insuring quiet operation and long dependable service. Automatic cam-operated switches provide accurate stopping at the desired limits. i Controls and Instruments Detroit Lubricator Company Detroit, Michigan, U. S. A. New York, N. Y., 40 West 40th Street Chicago, III., 816 S. Michigan Avenue Los Angeles, Calif., 320 Crocker Street Canadian Representative: Railway and Engineering Specialties Limited. Montreal, Toronto, Winnipeg Detroit Thermostatic Expansion Valve No. 673 Detroit valves are scientifically designed to keep evaporators completely refriger ated under all conditions. Orifice. sizes available from in. to J42 in. with capacities up to tons on Dichloro- difluoromethane or 6 tons on Methyl or Sulphur. . Detroit Ther mostatic Ex pansion Valves Nos. 781-783 and 785 Large capacity valves for air conditioning in stallations. Ca pacities up to 20 tons on Dichlorodifluoromethane and 35 tons on Methyl. Line Strainer illustrated available for large valves. No. 450 Series Refrigeration Controls Other features include alarm circuit, external "cold control," and high pressure cut-in for meat box applications, which prevents long "off" cycles and guards against ``slimy meat" in cold weather. Two-Eleven Room Thermostat A thermostat neat in ap pearance and of new design for heating, cooling or in combination' for both heating and cooling. Supplied with or without adjustable com pensator providing uniform control. Differential Thermostat No. 691 An inexpensive room thermostat for room cooling which modifies indoor temperature in accordance with outdoor temperature to maintain comfort conditions. Provides economy of operation and prevents shock due to over-cooling. Duct Damper Motor No. 431 Supplied in several models for various refrigeration and air conditioning re -. quirements. Line Voltage type. Model FB-3 con trols refrigeration compressor from pressure changes in the suction line. ` Model FIBA has, in addition, a high pressure cutout, which stops the compressor if high side pressures become excessive. Other models control from temperature changes. Range of either --40 to plus 25 or --5 to plus 60 is available. An inexpensive means of provid ing individual temperature control for zones or groups of rooms. Is quiet and can be mounted directly on the duct. Furnished with auxiliary switch to control heating equip ment. Neat in appearance and easily installed. Other Controls This Company can also supply you with Refrigeration Solenoid Valves, a full line of Boiler and Furnace Limit Controls-- Room Thermostats both high and low voltage for both heating and cooling--Fan controls--Humidity and Stoker Controls and Solenoid Valves for the control of water, fuel and gas. 914 Detroit Lubricator Company Controls and Instruments NEW IDEAL FAST-VENTING SYSTEM . For All One Pipe Steam Jobs -- New and Old There are three fundamental requirements for the venting of one pipe steam jobs-- . particularly when automatically fired. 1. Venting must proceed rapidly and be accomplished as early in the ON period of the burner as possible. 2. All radiators must start venting simultaneously. 3. Steam flow, to each radiator must be regulated in accordance with its location and capacity. It follows that most of the venting must be done before boiler pressure increases beyond a few ounces--also that large port large capacity valves are thus necessary. Large port low pressure venting has been made possible by the AUTOMATIC MODULATOR (patented). This permits full port action up to a few oz. pressure. Beyond that the AUTOMATIC MODULATOR reduces port area so as not to jeopardize subse quent venting at normal pressures. The No. 300 Arco-Detroit Multiport for radiators, is ideal for automatic heat as its construction permits much faster venting than the average air valve. The No. 861 Arco-Detroit Hurivent for mains, which has a H in. port area, vents with amazing rapidity and cannot be compared with the ordinary vent valve in performance. The No. 300 Multiport is adjustable over a wide range and its adjustment is proportional to the movement of the adjusting arm. Thus any system can be quickly arid accurately balanced, and when desired, the adjustment can be locked to prevent unauthorized tampering. Adjustment in no way interferes with the action of the AUTOMATIC MODULATOR. The No. 300 Multiport is new, modern, and very attractive--has a lustrous black molded jacket accentuated by brilliant chromium striping. Of great importance to the installer when necessary to "balance" the system, is the scientifically designed slide valve method of adjustment. The movement of this adjusting lever, which is located at the top of the valve, effects a corresponding adjustment of port _ area, and this adjustment is in direct proportion Hurivent to the distance through which the lever moves. Moving the lever over half its arc increases or decreases port area just 50%--moving the lever through a quarter of the arc changes port area 25%. Two straight shank valves designated as the 302 and 303 Multiports are furnished for concealed or "convector" type radiators. They have the same construction as the No. 300, except for the shank and all metal jacket. The No. 302 hasa in. connection and the No. 303 a % in. connection. nos straight Shank M ultiporl Experience with one pipe steam jobs has shown that such troubles as uneven heating, hard-to-heat rooms, etc., are fundamentally due to inadequate venting. Putting the No. 300 Multiport on each radiator and one or more No. 861 Hurivents on the main, eliminates all this and also improves fuel economy. Whenever a conversion burner or a new boiler is installed, all radiator and vent valves should be replaced to avoid complaints and dissatisfaction. . 1 915 Controls and Instruments The Bristol Company Waterbury, Connecticut Branch Sales and Service Offices Akron. Ohio Birmingham, Ala. Boston, Mass. Chicago. III. Detroit, Mich. Los Angeles. Cal. New York City Philadelphia. Pa. Pittsburgh, Pa. San Francisco. Cal St. Louis. Mo ' Seattle, Wash. The Bristol Company of Canada. Ltd., 64 Princess Street, Toronto. Ontario Bristol's Instrument Co., Ltd.. North Circular Road. London, N.W. 10. England A COMPLETE LINE OF INSTRUMENTS FOR RECORDING, INDICATING AND CONTROLLING ' ` TRAOE-MARK -------------------- BRISTOL'S----------------- -sso. u. . pat. orrtcs FLOW METERS, ELECTRIC AND MECHANICAL For indicating, recording, automatically controlling, and integrating flow of steam, air, gases, liquids. Electric Flow Meters telemeter measurements of flow any dis tance up to several hundred miles. Catalog No. 1051. RECORDING AND INDICATING RESISTANCE THERMOMETERS For securing, at a central point, readings of a number of temperatures at distant points. As many as eight temperature records can be made on one chart simul taneously. Catalog No. 11,52 and Bulletin No. 997. Eight-point Wide Strip Resistance Thermometer, Model 467 Electric Flow Meter. Model M 101,0 M Recording Pressure Gauge. Model 40M Recording Thermometer. Model S40M DIRECT READING RELATIVE HUMIDITY RECORDER Mechanical Flow Meter. Model 1140M RECORDING PRESSURE GAUGES For securing con tinuous records of pres-. sure, vacuum or liquid level for steam, air, gas, liquids. For ranges from full vacuum to 12,000 lb per sq in. Catalog No. 1025. RECORDING AND INDICATING THERMOMETERS Recording Ther mometer: For all commercial ranges from 60 F below to 1000 F above zero. For wall, flush or panel mounting. Cat alog No. 1251. Shows trend of hu midity and humidity conditions. No calcu lations or humidity tables needed. Re quires no water, no fan. Portable case. Catalog No. 1851. Right: Thermo-Humidigraph,' Model 4060 WET- AND DRY-BULB PSYCHROMETER Records wetand dry-bulb temperatures in kilns, drying rooms, air aucts. Self-contained and distance types. Mois ture-, fume-, and dust-proof case. For wall, and flush panel mounting. Cat alog No. 1251. Wet- and Dry-Bulb Psychrometer, Model 4&40M 916 Controls and Instruments Julien P. Friez & Sons (Division of Bendix Aviation Corporation) Baltimore Established Maryland in 1876 Manufacturers of a Complete Line of Automatic Electric Controls for industrial and Comfort Applications. Also a Complete Range of Recording and Accurate Measuring Instruments for Indoor and Outdoor Applications Humidstat -- accurate over long periods and com plete range; double length human hair element. Bulle tin AA. Thermostat -- sensitive, accurate for highest grade work. Bulletin TT. Comfortrol -- effective - temperature Thermostat re setting itself as prevailing humidity varies, using human hair compensating element. Hand Aspirated Psy chrometer--replacing `slings', no whirling; re liable, immediate reading; thermometers perfectly ventilated by typical air, in duced by venturi action with hand operated bellows. Ex clusive. Bulletin S. perature varies. Windowstat -- placed at window in doors, positively pre venting condensation from excess humidity. Controls humidity sup ply just below critical point as outdoor tem Exclusive. Bulletin W. Portable-Recorder-- for surveys or tests of humidity and tempera ture. Inked records on charts the size of filing cards (3" x 5"). Exclusive. Bulletin G. Microstat--Small sized ther mostat, featuring powerful Alnico magnets. Though priced with the lowest, unsurpassed for accuracy and fine appearance. Bulletin TM. Magnetic Gas Valve--New principle, free floating disc, no diaphragm; quiet, durable; range of sizes; low priced, low voltage, especially suited for control by Microstat pictured above. Exclusive. Bulletin VG. NEW! Hydraulic Action Remote Reading Temperature and Humidity Recorder--Electrically opera ted; humidity uniquely recorded from distant location directly in percent rela tive. Exclusive. Bulletin R. Limit controls for fans, furnaces, hot water, ovens, refrigeration. A new line of controls for long reliable service. Bulletins LC, TS and CR and Data Sheet 225. Write for Bulletins MODERN ADVANCED CONTROLS FOR MODERN NEEDS 917 Controls and Instruments The Fulton Sylphon Company Manufacturers of Sylphon Automatic Temperature Controlling Instruments and Packless Expansion Joints Knoxville, Tenn. ' Sales Representatives In Principal Cities PRODUCTS Automatic Radiator Valves, Air Conditioning Controls, Temperature Regulators for Storage Water Heaters; Ther mostatic Water Mixers; Re frigeration Temperature Re-' gulators; Packless Expansion Joints; Pressure Reducing Valves. GENERAL INFORMATION Fulton Sylphon Products depend upon the famous Sylphon* Metal Bellows for their trouble-free service and long life. Over thirty-five years ago, The Fulton Sylphon Company originated this bellows ... a precision-built, seamless, jointless "miracle in metal/' By continuous engineering study and intimate contact with heating and re frigeration Problems, this company has used this efficient, practically indestructi ble bellows in the development of a line of temperature control and heating special ties known everywhere for outstanding service and quality. SPACE HEATING AND AIR CONDITIONING CONTROL No. 885 Automatic Radiator Valve - For exposed radiation. Small, neat, finely finished, adjustable to room tem- . perature desired. Simply replace ordinary radiator valves with these . Sylphon Automatic Regu- . lators--no wiring, piping , or auxiliary equipment are required. These valves Sylphon No. W Automatic Radiator answer the demand for an False inexpensive means of pro viding accurate, depend able space temperature control in rooms, sections or throughout large buildings, new or old. Similar type valves for con cealed radiation--get Bulletin HVG-80. Sylphon Thermostats Heat accelerated and on- off types, with or without night set-back feature and with or without anticipating feature. No. 890 Electric Radiator Control Valve For either exposed or con cealed radiation. Similar in appearance and action to Sylphon. Automatic Valves, but operated by an electric wall thermostat. The closing of the thermostat circuit energizes a low voltage electric heater cpil surround ing a bulb containing a volatile liquid. This liquid expansion causes pressure on a bellows in the valve head operating the valve. This provides radiator valve control from a remote location, permits regulation of several radiators from a single thermostat, enables a time switch to be installed, if desired, offers effective zone control of large areas at a fraction of the cost of con ventional motor-operated valve systems. Bulletin HVG-70. No. 7 Temperature Control A self-contained, self-powered regulator for controlling unit heaters, wall or ceiling type radiators, heating coils in duct-type heating systems, etc. A sturdy control, quickly installed, holds temperatures within close limits. Valve is placed in steam line to Sylphon No. 7 Temperature Control XSdf-cperating) one or a battery of heaters, thermostat is mounted on wall or col umn. Designed fpr use on regular heating pressures up to 15 lb. Similar regulators, Nos. 7-2 and 7-3 for 50 and 75 lb pressure and temperatures up to 170 F. Bulletin HVG-50. / - No. 928-C Temperature Regulator A compact - regulator, especially suited to con trol of duct temperatures. Bulb is a series of copper coils, sensitive to slightest change in air temperature. Sylphon No. 9S8-C Duct Temperature Convenient adjustment. Regulator Three types for 15, 50 and 75 lb steam pressures and temperatures not exceeding 170 F. 918 Controls and Instruments The Fulton Sylphon Company No. 889-C Duct Temperature Control A'modu lating-, dual function regulator for control of duct heading and venlv^ting Sylphon No. 8S9-C Dual systems. Control for Dud Heating and Ventilating One of a broad line of Sylphon Instruments de veloped for modern air conditioning service. The No. 889-C is literally two controls in one--contains two independent valves in a single body. , Main valve is operated by adjustable' ductstat, and maintains de sired room temperature from temperature of recirculated air. Second valve, operated by low-limit ducstat, maintains minimum discharge air temperature on ventilating cycle and prevents objectionable drafts. Low-limit ducstat is compensated by a third bulb to maintain even discharge air temperature irrespective of demand. Write for new Sylphon air. conditioning control catalog No. HVG-820. Sent on request. \ No. 371 Damper Motor A positive type motor for on-and-off control of dampers. Operation Sylphon Damper Motort may be controlled by (Sdf-opcraHng and thermostat, hand ^ switch, motor starting switch, or other means. Motor, safety type, doses on current failure. Write for literature. Refrigeration Controls Adaptable wherever brine is used as the refrigerant. Latest No. 94S-Z development is a "freeze-proof" Regulator . valve (illustrated at left on the Showing detail .popular Sylphon No.945-ZRegulator). Bulletin HVG-20. PRESSURE REGULATORS No. 955--Sylphon Inter locking Valve is a safety appli ance protecting oil-fired fur naces by shutting off oil flow should atomizing pressure fail or fall below the required mini mum. Approved by Associ ated Factory Mutual Fire Insurance Companies. Bul letin HVG-100. No. 956 Interlocking Valve HOT WATER SUPPLY No. 923 Temperature Regulator For controlling tempera ture of water in heaters, open or dosed tanks and various types of equipment. Operation is unaffected by temperature fluctuations at the valve, either above or below bulb temperature. Neat. Compact. All parts, No. *99 Temperature Regulator except steel adjustment spring, made of non-ferrous metals. May be installed in any position. Ranges from 40 -- 80 F to 290 - 330 F. Bulletin HVG-20. Above No. 906 Ther mostatic shower mixer with temp erature selector handle permit ting setting for any desired, ther mostatically maintained, temperature from cold to a safe maximum temp erature of hot water. ' uhmct yiessure. PACKLESS EXPANSION JOINTS The Sylphon Packless Ex- , pansion Joint eliminates use less building height, expen sive construction and non revenue producing space. No costly leaks and repairs, * no repacking,always tight, allows beating system to operate at ' full efficiency. Write for Bui- letin HVG-140 V Ho. no Sylphon fclKT Sylphon Thermostatic Water Mixers Utilize hot water from any storage tank or instantaneous heater, and effectively regulate the amount of cold water required to temper it to the desired degree, actually, mixing the hot and cold water together before delivery. Temperature remains constant in spite of fluctuations in supply water temperatures or pressures. Four sizes with capacities ranging from 5 to 131 gpm. Bulletin HVG-40. 919 Controls and Instruments Henry Valve Company 1001-19 North Spaulding Ave., Chicago, 111. Manufacturers of complete line of Dryers, Strainers and Line Valves for Freon and Methyl Chloride. Also Ammonia Valves and Forged Steel Fittings. ABSO-DRY PRESSURE SEALED DRYERS For Refrigeration and Air Conditioning Exclusive Henry vacuum process first re moves every trace of moisture,then thedryer is charged with dehy drated air. Loosening seal cap produces hiss ing sound, a guarantee of original factory dryness. OTHER FEATURES OF HENRY DRYERS--Perforated Dispersion tube is connected to inlet port and exposes entire volume of dehydrant to penetration by refrigerant. Minimum pressure drop. No channelling. Compression Spring main tains uniform tension on dehydrant at all times and compensates for changes in volume. Soldered or Flanged Shells-- models are available with either soldered cap or flanged end shells. Flange is dis tortion-proof. Shells not exceeding 5H in. in length are drawn in dies, so that they have only one joint. FOUR DEHYDRANTS--Choice of following dehydrants at same price: Ac tivated Alumina, Calcium Chloride, Calci um Oxide and Drierite. Type 744 Cartridge Dehydrator A flanged shell dehydrator with replaceable cartridge. Type 712 Dehydrator HENRY STRAINERS There is a size and type of Henry Strainer for every installation requirement. Type 895 "Y" Strainer With sold er fittings for use with cop per pipe. . Exceptional design. Welded steel construc tion. Negligible pressure drop. Screen can be taken out for cleaning without removing strainer from line. Very large screen area. Light weight. Baffle prevents heavy particles injuring screen. Type 896 Strainer with Felt Sack For use where an exceptional degree of filtration is required. Felt sack is sup ported inside of 100 mesh screen cylinder. WING CAP VALVES Designed especially'fOr Freon and Methyl Chloride. Have patented ^rotating self aligning stem disc. Special resilent pack ing. May be repacked under pressure. Wing cap can be inverted and socket used for operating valve. Screw end, soldered and flanged connections. Soldered brass shell dehydrator with dis persion tube and compression spring. AUTOMATIC RELIEF VALVE Angle type with push rod for emergency reseating. Available pressure settings: 90 to 250 lb. Approved for use under many refriger ating and air conditioning safety codes. FREE CATALOG It describes the complete line of Henry Dryers, Strainers and large line valves used in refriger ation and air con ditioning. WRITE FOR IT 920 Controls and Instruments Illinois Testing Laboratories, Inc. 422 N. LaSalle Street, Chicago, Illinois TESTING ENGINEERS AND MANUFACTURERS Pyrometers--Portable--Wall Type--Surface Temperatures Distant Reading Resistance Thermometers Automatic Temperature Controllers ' Air Velocity Meters "ALNOR" VELOMETER The Only All-Purpose Air Velocity Meter agiitgiyaawHa ItaaaaiaiPS Velometer with averaging jet used for checking velo city from supply grille. The Velometer is a versatile direct reading air velocity meter which gives instantaneous readings of the speed of air measured in feet per minute. Anyone can use the Velometer. No mathematical calcu lations, no leveling--no timing. As its movement is actuated by the pressure or impact of the air against a swinging vane, it is essentially a pressure instrument--thus it can be scaled to not only read velocities directly, but also to read static or total pressures when using suitable jets. Made in standard ranges for velocity readings from 20 fpm to 6000 fpm and 3 in. static or total pressure. Special ranges available as low as 10 fpm and up to 24,000 fpm velocity and 20 in. pressure. Jets--Several standard jets are offered providing a wide application. Spot jets--for velocities over very small area. ' Averaging jets--for obtaining average velocities over a definite area or grille face. Duct jets--for determining velocities directly within ducts or pipes. Static pressure jet--for static pressures in inches of water. Total pressure jet--for total pressure in inches of water. Other jets--Standard jets offered in several lengths and sizes. Special jets--can be designed for unusual applications. ' Ask for Bulletin No. 2448-C "ALNOR" DISTANT READING ELECTRIC THERMOMETERS The use of "Alnor" multi-point resistance type thermometers is rapidly increasing not only in air-conditioning, but also for heating and refrigerator installations. The instrument can be located in the machinery room or boiler room with the elements located on various floors in any part of the building, or outdoors, thus providing the engineers with constant and convenient temperature readings. "Alnor" thermometers are made in several styles and sizes, both portable and mounted types. Ask for Bulletin No. 2451 -A 921 "Alnor" round type multi-point resist ance thermometer with built-in switch. Controls and Instruments Johnson Service Company AUTOMATIC TEMPERATURE AND AIR CONDITIONING CONTROL General Offices and Factory Milwaukee, Wis. Branch Offices In all Large Cities > Johnson Temperature Regulating Co. of Canada. Ltd., 113 Simcoe St., Toronto, Ont. Montreal, Que. Winnipeg, Man. Calgary, Alta. Vancouver, B. C. Products and Services Manufacturers, engineers, and contractors for Automatic Temperature and Humidity Control Systems applied to all types of heating, cooling, ventilating, and air conditioning installations. Also, for every range required in manufacturing and industrial processes. A single nation-wide organization devoted to Design, Manufacture and Installation tor more than 50 years. Room temperature control applied to radiators, unit ventilators, and heat delivery ducts. Johnson "Duo-Stats" to maintain the proper relationship between outdoor and radiator temperatures for groups of radiators or "heating zones." A complete line of devices for automatic control of air conditioning systems, heating, coioling, humidifying, dehumidifying. Automatic seasonal shifting of control cycles. Periodic Flush Systems for intermittent flushing in various sections of a building, reducing load on piping system and insuring economy in use of water. Special bulletins and catalogues on request. Sales Engineers at direct branch offices in all principal cities. Johnson All-Metal Thermostats Johnson thermostats, room, insertion, and immersion types, are all metal throughout, no soft or hard rubber parts to deteriorate and become inoperative. Every thermostat precise in construction and thoroughly tested for accuracy, efficiency, and durability. The Johnson intermediate action thermostat gives a true graduated action to mixing dampers and valves. It holds them in an intermediate position to maintain the temperature of the room accurately within Room Thermostat one degree above or below the setting of the thermostat, if desired. Johnson "Dual" or Two-Temperature Thermostats The Dual, two-temperature, room thermostat especially adapted foruse where various rooms or groups of rooms are occupied when the remainder of the building is not in use. Separate steam mains avoided. The shifting from "day" or occupancy temperature to an economy temperature for "non-occupancy" conditions, accomplished by a switch or Johnson program clock at a central point. Push buttons on the thermostat are provided when "occupant control" is desired. Dual thermostats are all-metal and operate valves and dampers gradually to maintain temperature accurately within one degree. Dual Thermostat Johnson Valves and Damper Motors Johnson diaphragm valves are simple and rugged. Seamless metal bellows or moulded rubberdiaphragms, super-aged and heat resistant, and heavy spring operate the valve stem. No complicated moving parts. Made in all sizes and patterns, for various pressure ranges. For steam, water, brine, gas, and special services. Direct acting (normally open) or "Sylphon" reverse acting (normally closed). Standard or special Radiator Valve modulating discs . . . Also, three-way mixing and by_ -p. ass valves . Pilot operated valves for precise positioning and smooth, gradual control, regardless of pressure fluctuations ... A wide variety of motors, similar to valve tops, to control dampers and other devices which require lever operation. Room Humtdoslal 922 Johnson Service Company Controls and Instruments Humidostats and Humidifiers The Johnson Humidostat automatically controls the supply of moisture delivered to the air by a humidifier or air washer and maintains a constant percentage of relative humidity. Available in both room and insertion patterns, and with various types of elements as determined by requirements, controlling within 1 per cent at relative humidity of 95 per cent and 100 F if desired. Johnson humidifiers are furnished in steam "grid" type or pan type with copper evaporating pan, brass heating coil, and float control. Air Conditioning Control Summer-Winter room thermostats for operation of valves and dampers in reverse sequence for cooling and heating. Four-Point Insertion Thermostat Insertion and immersion thermostats in one, two, three, and four-point patterns for operating valves and dampers suc cessively at different temperatures. Remote readjustable thermostats, reset from a distant point by pilot or differential thermostat or by pressure switch. Differential thermostats to maintain desired temperature differences between two points, such as outdoors and treated space. Solenoid air switches, manual switches, static pressure regulators, velocity regulators, and all types of dampers to regulate flow of air in ducts. The Johnson sensitivity adjustment is an important development in the field ol automatic temperature and humidity control lor air conditioning. A unique and convenient means of adjusting the sensitivity of Johnson thermostats and humidostats on the job, with respect to the capacity of the conditioning apparatus; Zone Control Johnson "Duo-Stats" to regulate the flow of heat in a group of radiators constituting a "heating zone" by maintaining the proper relationship between outdoor and radiator temperatures. Summer-Winter Thermostat Process Control Remote Readjustable Duct Thermostat Calibrated insertion thermostats for control ling temperature of liquids, air and gases. Mercury extended tube thermostat for remote location of sensitive element. Wet-bulb thermostats for dose regulation of humidity. "Record-O-Stats," combination instruments to record and control tempera- mentforExpa^ion tures. Valves Controls and Instruments Leeds & Northrup Company General Office and Works: 4941 StentOn Avenue, Philadelphia, Pa. Branch Offices: Boston Buffalo Chicaco Cincinnati Cleveland Detroit Hartford Houston Los Angeles New York Pittsburgh St. Louis San Francisco Tulsa ' RUGGED, ELECTRICAL-BALANCE INSTRUMENTS Model S Micromax Recorder Record* from l to 16 potnil on a tingle ttripchart Bztremely open record. Con operate rignal*. (A&oul t/lSth tie*) Model R Micromax Recorder Record* I or t votn/t on a round- chart, Ha* extremely readable dial. Can operate rignal*. (About t/JSth rite) Switchboard Indirator Hand-operated. Can be connected through trieetor rritchee to any number of pointi, (A&oul l/ltth cue) Electrical Thermometers for Air Conditioning Electrical Instruments for the Steam Plant No method for measuring temperatures fits the specific needs of air conditioning as does the three-lead null-type resistance thermometer method. It is independent of distance and disregards all temperatures except those right at detector locations. The detectors (resistance thermometer bulbs called Thermohms), can be placed anywhere--in rooms, air ducts or water lines. They are connected by simple elec The facts needed to operate a modern heating plant so as to save fuel, to protect equipment, and to operate efficiently at varying loads are provided reliably by rugged L&N instruments. Readings can be indicated or recorded or both. Re corders can be equipped to operate signals or alarms that warn the operator of extreme conditions. In some cases the instruments controi^automatically. trical wiring to instruments at a central location. Instruments may be: Micromax Recorders, Model S for up to sixteen Thermohms, Model R, for related pairs such as wet and dry bulb; indicators with switches for any number of Thermohms; or indicating and recording combinations. Micromax Model S provides a per manent record of conditions at from 1 to 16 points on one wide-scale chart. Micro max Model R concentrates on conditions at one point, provides a permanent record, and has a giant indicating dial that can be read at a glance. The switchboard in Sound in principle, this equipment is dicator provides intermittent checks on reliable in operation. Instruments and conditions at one or several points. Thermohms are highly responsive, yet rugged in construction. A complete system In the heating plant, L&N measuring, is easy and economical to install, regardless signalling or controlling equipment is of distances. It is easy to operate and used for: demands minimum maintenance. Therm ohms and instruments are interchangeable, Metermax Combustion Control and can be replaced without disturbing Furnace Pressure Control. wiring or returning anything to the factory. Smoke Density Analysis. L&N Resistance Thermometers make it possible to operate efficiently; to maintain comfort or correct process atmosphere con stantly ... so that maximum return is Flue Gas Analysis (Percent CO,). Flue Gas Temperatures. Steam and Water Temperatures. Boiler-Furnace Temperatures. realized on the conditioning investment. Electrolytic Conductivity of Water. J-N-225(2) 924 Controls and Instruments ASHCROFT AMERICAN GAUGE DIVISION AMERICAN SCHAEFFER & BUDENBERG INSTRUMENT DIVISION , Manning, Maxwell & Moore, Inc. Bridgeport, Conn.--branches in principal cities .' Makers of AMERICAN INDUSTRIAL INSTRUMENTS--Since 1851 Manufacturers of Indicating and Recording Gauges; Gauge Testers: "U" Gauges; Draft Gauges; * Indicating and Recording Thermometers; Tachometers; Dial Thermometers; Pressure and Temperature Controllers; Electric Temperature Controllers; Pop Safety and Water Relief ^ Valves; Steam Traps; Absolute Pressure Gauges. V. .! Also manufacturers of Bronze, Cast Steel and Forged Steel Valves, Engine * Room Clocks; Barometers; Mercury Column Gauges; Gauge Boards. Ashcroft American Gauges--Ashcroft American Gauges are made in all sizes from 2)4 to 12 in., for pressures from 8 oz to 25,000 lb and also for vacuum. Cases are cast-iron or cast brass. The move ments are heavy duty and all bear ings are Monel Met al. Write for Cata log No. A-59. Also Duragauges --accurate to within of 1 per cent. Stainless steel movement. In Phenol Cases in 4)4 >n., 6 in. and 8)4 in. dial sizes. For Mercury Pressure and Vacuum Gauges, "U" Gauges, Draft Gauges and Mercurial Barometers, write for Catalog B-59. Recording Duragauges--Recording Duragauges are made for all pressures from 15 in. of water to 10,000 lb and for vacuum. They are made in one size only to accommodate a 10 in. chart, having an effective scale width of 3M in. The case is die cast with a dull black hardrubber finish and with either bottom or back connection. The pen-arm is made of non-corrosive monel, metal and is of the inverted type. Operating instructions are lithographed on the chart plate so that they cannot be lost. Write for Cata log E-59. American Air Duct Thermometer-Designed especially for both warm and cold air ducts. Fitted with chromium plated frame, glass front. Fur nished with 9-in. or 12-in. scale graduated 0-160 F. Write for Catalog F-59. American Recording Thermometers-- Made for recording temperatures from minus 40 to plus 1000 F or equivalent C. Very flex ible connecting tubing up to 200 ft. One size to ac commodate 10 in. chart, with an effective scale width of in. Same case as for the American Recording Gauge, so that all instru ments are uniform in ap pearance when mounted on Gauge Boards. Write for Catalog H-59. American Dial Thermometers--Ameri can Dial Thermometer (mercury-filled) has the accuracy of the standard glass tube thermometer and the ' reading convenience of a dial face. Entire working mechanism is made of steel, meaning long life. Six sizes, ranging from 4)4 in. to 12 in. diameter dials. Furnished with rigid connection or flexible capillary tubing up to 200 ft. For temperature ranges from minus 40 to plus 1000 F. Write for Catalog G-59. American Precision Temperature Controllers-- Self-operated. For regulating temperatures from 20 to 325 F. For hot water service tanks, water heaters, etc. Size of valve must be speci fied. Write for R-59 Bulletin. 925 Controls and Instruments Minneapolis-Honeywell Regulator Company 2711 Fourth Ave., So., Minneapolis, Minn. Cable Address: Minnreg, Minneapolis Electric or Pneumatic Control Systems for Heating, Ventilating, Air Conditioning BROWN INSTRUMENTS for Indicating, Recording, Controlling Factories: MINNEAPOLIS, MINN., PHILADELPHIA, PA., WABASH. IND., CHICAGO, ILL. Branch Offices or Distributors are located in all principal cities. -1 Albany, N. Y. Dallas Allentown Davenport. Ia. Atlanta Dayton Baltimore Denver Birmingham ` Des Moines . Boston Detroit Bridgeport, Conn. East Orange Buffalo Eau Claire, Wis. Butte El Paso, Texas Charlotte. N. C. Fairhaven. Mass. Chicago Fargo, N. D. Cincinnati Hartford Cleveland Harrisburg, Pa. Columbus Haverhill, Mass. Houston Indianapolis Jackson, Mich. Kalamazoo Kansas City Los Angeles Louisville, Ky, Lowell, Mass. Mason City. Jowa Milwaukee Minneapolis Nashville New Orleans New York Oklahoma City Omaha Peoria Philadelphia Pittsburgh Portland, Me. Portland, Ore. Providence Richmond, Va. Rochester, N, ^ St. Louis Salt Lake City San Antonio San Francisco Scranton Seattle Sioux Falls. S. D. Springfield, Mass. Syracuse Toledo Tulsa Washington, D. C: Wichita Worcester, Mass. Youngstown In Canada: Montreal, Toronto, Calgary, Vancouver, London, Winnipeg In Europe: Amsterdam, Holland; London, England; Stockholm, Sweden AUTOMATIC CONTROLS FOR EVERY APPLICATION Minneapolis-Honeywell is ready to assume thecomplete responsibility for the supply and installation of automatic controls and instruments specified for any building that you design. M-H serivce is complete. Through our nationwide organization, we are pre pared to make complete installation, supervise installation, provide periodic service or supply control equipment. Minneapolis-Honeywell can offer unbiased advice on your control requirements--manufacture and install complete electric control systems, complete pneumatic control systems, or a combination of the two. Each MinneapolisrHoneywell office maintains a factory trained personnel. Your Minneapolis-Honeywell office will be glad to furnish you with recommended control layouts and cost estimates. He is trained to recommend control results^before installation of equipment and to produce control results aftef the-installation has been completed. . THE MODUTROL SYSTEM OF ELECTRIC CONTROL Duel Type Tempera The Modutrol System designation is applied to any combination ' ture Controller of Minneapolis-Honeywell Automatic Electric or Pneumatic Controls or Self-contained Automatic Valves used to govern the operation of air conditioning or heating systems other than the small domestic installations. A wide variety of both modulating and two position motors, controllers and valves are available thus making the Modu trol System extremely flexible as to the selection of control equipment to produce the desired results. Modulating Motorised Valve Complete electric control systems are available for those instal lations where precise, flexible and dependable results are required. Electric controls of the Modutrol System provide a dependable means of effecting modulation through the use of the "Series 90" control circuit. All electric motor power units used in this system are completely oil immersed in order to insure quiet operation and years of trouble-free service. 926 Minneapolis^HoneyWell Regulator Co. Controls and Instruments "Gradustal" Pneumatic Thermostat THE GRADUTROL SYSTEM OF PNEUMATIC CONTROL Minneapolis-Honeywell offers a complete line of pneu matic controls. To such features as "Helmet Seal'* Ther mostats and Metaphram construction of valve and damper motors has been added the accurate and infinite positioning of the Gradutrol Relay. For commercial air conditioning and space heating installations, the Gradutrol System offers a truly remarkable advance in pneumatic control. COMBINATION ELECTRIC AND PNEUMATIC SYSTEMS The outstanding advantages of both the electric Modu trol System and pneumatic Gradutrol System of control may be combined in a single installation. Thus maximum flexibility and low, installation cost are obtained. Minneapolis-Honeywell can offer either an electric or pneumatic system, or a combination of the two. This is your guaran tee of an unprejudiced recommendation. Gradutrol Motor and Damper. Brown Recording Thermometer and Pressure Gouge BROWN INSTRUMENTS The extent to which air conditioning equipment is being used in office buildings, theatres, stores, industrial buildings, etc., has opened up a wide demand for indicating and recording resistance thermometers because the temp eratures throughout these air conditioning systems should be checked periodically in order to obtain the best results at minimum operating cost. To obtain uniform conditions from modem equipment, it is necessary that the engineer in charge of operation have a visual picture of actual conditions. Brown Resistance thermometers are available for in dicating, recording, and controlling service and are applicable to all types of air conditioning and space heating installations. In addition to Resistance Thermometers, The M-H Brown Instrument Division manufactures:. Thermometers Hygrometers Pressure Gauges Vacuum Gauges Potentiometer Pyrometers Flow Meters CO2 Meters Tachometers Liquid Level Gauges .Protectoglo System RESPONSIBILITY FOR ENTIRE CONTROL SYSTEM Minneapolis-Honeywell Regulator Co. is equipped to assume the entire responsibility for any control installation, thereby eliminating the difficulties and misunderstandings which division of responsibility may create. Brown Recording Resistance Thermometer 927 ' Controls and Instruments The Mercoid Corporation SOLE MANUFACTURERS OF THE MERCOID SWITCH Main Office and Factory, 4201 Belmont Ave., Chicago, III. Branch Offices: New York, N. Y. 330 W. 34th St. Philadelphia, Pa. . 3137 N. Broad St. Boston, Mass 839 Beacon St!* Distributors and Jobbers in all Principal Cities COMPLETE LINE OF AUTOMATIC CONTROLS AND MAGNETIC VALVES FOR HEATING AND AIR CONDITIONING Mercoid Controls are equipped throughout with sealed mercury contact switches. These switches cannot be affected by dust, dirt or corrosive gases. They are not subject to open arcing, pitting or sticking of contacts. Mercoid switches will operate indefinitely without deterioration. Write for catalog No. 300AS. SENSATHERM Extremely sensitive ther mostat which requires no artificial stimulation to main tain an even room tempera ture. Operates on tempera ture variation of H deg above or below point set (total dif ferential 1 F). Small in size, neat in appearance and un failing in performance. TRANSFORMER-RELAY luXHB (VRSBB A reliable low voltage mer cury contact relay which also acts as a transformer inducing low voltage (24 volts) on the pilot circuit. Does away with all hum and chatter. Avail able for 115 or 230 volts, 60, PRESSURE AND TEMPERATURE LIMIT CONTROLS These instru ments have proven their reliability over a long period of years. The outside double adjustment provided with a calibrated dial, is a special feature that saves considerable time when making the neces sary operating adjustments. Available for steam, hot water and warm air furnaces. These controls are also used for various industrial applications. COMBINED PRESSURE AND LOW WATER CONTROL Type DA-121 low water and pressure controls have the new double adjustment feature which saves guess work and time in installation. Pre vents firing into dry boiler and building up excessive steam pressure. Various types and ranges available. OIL BURNER SAFETY CONTROLS Type RM1 provides positive protection against flame or ig nition failure on burners em ploying intermittent spark or . gas ignition. Recycling feature automatically restarts burner . under fluctuating flame, con- , < ditions, however in event of ignition failure, burner goes to safety shutdown. Other types available. STOKER CONTROLS Type THV Stok-A-Timer maintains fire during periods when thermostat does not call for heat. Has heat motor which operates a gearless mechanism having but one ro tating member that turns at rate of 1 rpm. The slow oper ating speed is a feature which reduces wear and tear. 928 Controls and Instruments The Palmer Company Mam plant: 2506 Norwood Ave., Cincinnati (Norwood), Ohio Canadian Factory: The Palmer Thermometer Co., Ltd., King and George Sts., Toronto Manufacturers and Originators--"Red-Reading-Mercury" Thermometers MANUFACTURERS--Complete line of Thermometers. RECORDING THERMOMETER (Mercury-actuated) A NEW product produced by PALMER in 1939, after years of research and tests so that this Recorder is the finest instrument on the market. POCKET THERMOMETERS Ranges + 20 + 120 F. 0 + 220 F. Indicating and Maximum-Register- raj) ing styles. With RED col- _ rill LABORATORY THERMOMETERS From 6 in. to 24 in. lengths; Round or lens glass; with or without armor; from 2 deg div. to Jfo deg. Made of selected glass, treated and annealed for per manent accuracy. With RED column. PSY- CHROMETERS Also Hygrome ters. Wet and Dry Bulb for testing hu midity. Easy to read with RED col umn. Writefor Bul letin No. 500-A. No. 1SS40 Write for Bulletin No. 1800. PALMER Recorder guaranteed to give satisfactory results by a firm who knows how to make good instruments. INDUSTRIAL THERMOMETERS PALMER patented "Red- Reading-Mercury" feature is furnished at no extra cost. A pure mercury tube with a bright RED column which is so easy to read. ' Alt styles and fittings. ' Standard ranges: - 20+120 F 0 -HOOF -f 30+180 F -4-30 +240 F and higher. Write for Catalog No. 200-E. DIAL THERMOMETER ( Mercury-actuated) Another 1939 PALMER prod uct. Constructed to be the'best. With flexible tubing connection. No. lilOO Write for Bulletin No. 1500. *** REPAIRS TO ALL MAKES with "Red-Reading-Mercury" No. 327 at no extra cost. Guaranteed to give satisfactory results. It's a PALMER product. Specify PALMER next time! 929 Controls and Instruments The Powers Regulator Co. 48 Years of Specialization in Temperature and Humidity Control Offices in 47 Cities -- See your phone directory. Genera) Eastern Office General Office* and Fsctory 231 East 44th St., New York Ofj' 2720 Creenriew Ave., Chicago, III. Altaar Alkali' fiiltinan Biminffcais Boston `Beffalo Butt* Cal*rjr Cttattaooaes Chicago Cincinaati Cleveland. Cotumbtt Dallaa Dat Det'Moii n Detroit El iSw Greenoboro Halifai .Hartford Honolulu Houilon lodianapolts Jacksonville Kansas City Los Angde* Mempbb .Mijaauitt Mianapolia The Canadian Powers Regulator Co-, Ltd. 193 Spadina Are., Toronto, Ont. Mootree! NasbviU. New Orleans New York (JiUboraa Cily Philadelphia Piltitxirgii Portland Rochester St. Louis .Soil Lake City San Anlooio Sts FruruM/ Swam* Vaecev*<* Winnipeg' PRODUCTS--A very complete line of com pressed air operated and self-operating tem perature, humidity and air flow controls for automatically regulat ing heating, cooling, ventilating and air conditioning systems and industrial processes. - A complete line of self-operating and compressed air operated valves and. regulators made for: Control ling steam heated hot water heaters and submerged type heaters; and for automatically mixing hot and cold water or steam and cold water delivering a mixture at a pre determined temperature. ' Dial Indicating and Recording' Ther mometers. Thermometer-Regulators. High pressure steam, traps`and pres sure reducing valves. : * Powers Compressed Air Operated Apparatus The Powers Regulator Co. Controls and Instruments Compressed Air Operated Apparatus--Continued Three of the Many Types of Powers Self-Operating Regulators i i i 930 POWERS ENGINEERING SERVICE As the accurate performance of a heat ing, cooling, ventilating or an air condi tioning system, or an industrial process is so dependent upon its automatic control equipment, and as the cost of such control is but a fraction of the entire system, the use of the proper type of regulation is always sound economy. To secure the maximum return on the in vestment in automatic control equipment, it is exceedingly important that proper selection of control apparatus be made when each installation is being planned. Forty-nine years of experience in fur nishing and installing temperature . and humidity control for every conceivable purpose in all types of buildings have given us a wealth of experience from which you can draw in selecting the proper type of control for any purpose. . CATALOGS AND BULLETINS de scribing any or all of our products fur nished upon request. Phone or write our nearest office. See your phone directory. . Controls and Instruments Penn Electric Switch Co. Goshen, Indiana Offices--New York, Boston, Philadelphia, Detroit, Dayton, Chicago, Moline, (111.') St Loitu Export--100 Varick St., New York City '' Representatives--Garland-Affolter Engrg. Corp., San Francisco, Los Angeles, Seattle, Portland* Monarch Sales, Denver; Forslund Pump and Machinery Co., Kansas City- ' ' Vincent Brass and Copper Co., Inc., Minneapolis; D. J. Bowen, Dallas. ' ' In Canada--Powerlitb Devices Ltd., Penn Electric Switch Div., Toronto, Ont. * Distributors and Jobbers in All Principal Cities . * . Automatic Controls for Heating, Refrigeration, . Air Conditioning, Pumps, Air Compressors Tem-Clock Temtrols Oil Burner Stack Switches Solenoid Gas Valves Temperature and Humidity Controls For control of tempera tures and humidity in heating, cooling and air' conditioning equipment:- Humidistat Combustion Controls for all Fuels. For automatic fuel burn ing equipment, and for stack combustion control. Damper Motors Heavy Duty Thermostats Stoker. Timer Relays Cut-offs and Feeders Boiler and Furnace Controls For feedwater, steam pres Steam Pressure sure, liquids and warm air. Controls Liquid Immersion Tempera- ture Controls Worm A ir Bonnet Controls Refrigeration Compressor Controls Water and Refrigerant Solenoids Many Others For control of refrigerants, water and air; and for pumps and compressors. Water Valves Pump and Air Compressor Controls Write for catalog on Penn Controls to sentative. Penn engineers always are cover your particular applications, or available for consulation on control prob 'phone the nearest Penn office or repre lems, without obligation, of course. Penn control engineers hare simplified design and production problems for others! Let them assist you. 932 Controls and Instruments Spence Engineering Company, Inc. 28 Grant Street, Walden, N. Y. SPENCE METAL DIAPHRAGM "DEAD END" REGULATORS Advantages of Spence Regulators Dead-end Shutoff--Spence Regulators are guaranteed to hold a dead-end. Single Seat--Spence design makes possible a balanced single seat even in . large sizes. . Metal Diaphragms--Under normal conditions never require replacement. - Accurate Regulation--Regardless of r fluctuationsineitherloadorinitialpressure. SECO Metal--Guaranteed to resist the wiredrawing action of steam. Interchangeable Pilots--Any type-of pilot will fit any size main valve. Accessibility--Pilot is connected to main valve with unions. No Stuffing Boxes--All main valves and most pilots are packless. Spence Weather Compensator and Orifice Zone Control System , This simple, dependable Control, O f) Q when installed on a-properly de r" signed orificed heating system, will _ L, show a substantial degree-day steam saving, at a low maintenance cost. The delivery pressure of the Regulator is automatically adjusted in direct proportion to the building heat losses. In other words, as the losses become greater, steam pres sure on the system is automatically increased. Any number of zones can be con trolled by one automatic Signatrol, automatic Wind Loss Compensator (Anemometer). Time Switch arid Master Control Panel equipped with Manual and Automatic Dials for each zone. In this way each zone can be set individually and at the same time be under the Master Control. Pressure Regulator-- Type ED Designed to regulate a steady or varying initial pressure so as to maintain a constant, adjustable, de livery pressure. Applica ble to heating systems, power plant operations, or manufacturing processes. Combined Temperature and Pressure Regulator --Type ETD Self-contained, pilot oper ated, dead-end. Designed to control flow of fluid to a heating or cooling element, so as to maintain a constant, adjustable temperature, and. Electrically Operated Valve--Type EM Can be opened or closed independently by an elec trical switch. TypeET--Same as ETD except pressure control is omitted. protect the element against Order a SPENCE Regula excessive pressure. tor for 40 days' free trial. 933 Controls and Instruments Jcujlx)r IruirMmjmt ComjuuiitA Rochester, N. Y., U. S. A. ' IN CANADA--Taylor Instrument Companies of Canada, Ltd., Toronto NEW YORK CHICAGO BOSTON PHILADELPHIA PITTSBURGH CLEVELAND LOS ANGELES INDIANAPOLIS SAN FRANCISCO ST. LOUIS CINCINNATI TULSA DETROIT ' ATLANTA MINNEAPOLIS Manufacturing Distributors in Great Britain, Short & Mason, Ltd. London Taylor Instruments for Indicating, Recording and Controlling Temperature, Pressure, Humidity, Flow and Liquid Level . Taylor Industrial Taylor Electric Con Thermometers--with new "BINOC" Tubing --Includes many' styles and scale ranges with *1aulor tact Temperature Control -- Combine in the same case an elec trically operated tem bulbs for every perature controller with application. an indicating thermome These ther ter. One tube system mometers contain a new and operates both units. radical development of tremen dous importance -- "BINOC' Tubing. This newly designed and optically correct glass tubing assures an ease of reading that has been generally lacking in industrial thermometers. "BINOC" Tubing more than doubles the angle of vision within which readings can be made. Because of the pat ented Triple-lens con struction, its broad mercury column can be read easily and accurately with both eyes. Bore reflection is absent. The New Taylor "Fulscope" Re cording Controller -- An air operated controller that gives practically any character of process control regardless of time lag in apparatus. Available for controlling temperature, pressure, hu midity, rate of flow, liquid level. Where extreme load changes or badly balanced operating con ditions exist, Taylor "BINOC" Pocket Test Thermometer--Ideal for frequent testing of important temperatures. Taylor patented "BINOC" Tubing eliminates juggling and guesswork. precision con trol can be maintained by the automatic reset feature. High accuracy--3 Times Easier to Read. New Taylor Indicating "Fulscope" Controller--For Taylor Record ing Thermome ters--Tem pera t u re ranges and time re quirements vary greatly in heating and ventilating work. Taylor Re corders are made in control applications where a high-quality air-operated control ler is desired for sensi tive regulation, but a record is not required. Available for temper ature, pressure, flow and liquid level. needed scale ranges Taylor Type-P Controller--A compact and time periods. and very sensitive These efficient in air-operated con struments are troller, ideal for air- < particularly adapt ducts, air-washing ed for heating and air conditioning appli machines, cooling cations. Furnished for surface or flush rooms and similar mounting. applications. 934 Taylor Instrument Company Controls and Instruments Taylor Self-Acting Taylor Re Temperature Con cording Hy troller--Adapted for grometer-- use on hot-water Records both storage tanks, etc. Re wet- and dry- quires' no auxiliary bulb tempera motive power. tures on the The valve can be same chart in closed at any desired different color temperature, or a ed inks, mak throttling action can ing comparison be obtained. Not prac very easy. ticable on pipe lines Type shown having steam pressure has motor- over 125 lb. driven fan for conditioned rooms or pass ages where circulation is poor. Furnished :S - without fan for installations where circula Taylor Dial Thermometers for air ducts or any application where it is desirable to have temperature readings at some distance from the thermometer bulb, as in a central con trol room. Can be read at a glance as easily as a steam gage. tion across bulb is good. Taylor 10BG Hy grometer-- For air ducts and closed compart ments. Com bines the accuracy of an etched stem ther mometer with the rug gedness of an SIS i nd u st ria l Taylor Sling Psychrometer--The advantage of this form of Wet- and Dry-Bulb Hygrometer over the stationary form is the facility with which tests can be made and the accuracy of the readings obtainable, as the whirling bulbs are sub jected to perfect circulation. Two accurate etched stem thermometers are mounted on a die-cast frame, with the bulb of one covered with a wick to be moistened. These thermometers have scales of 0 to 100 F, gradu ated in j^-deg divisions. A copper case protects the tubes when not in use. thermometer, Complete assembly swings out on bracket for quick and easy inspection by loosening two thumb screws. Numerals etched on broad, flat tubes and pigment filled. Tube scales mounted horizontally for quick reading. Specially designed guard allows maximum circulation with minimum risk of breakage. Water supply from beer bottle reservoir, as shown;, or from a tap-fed, constant level reservoir. Taylor Humidiguide--A hand some small hygro meter for the wall of the home, office, school or other building where a neat, easy-reading and inexpensive instrument is de sired. It is self- contained, requir Taylor Biram's Ane mometer--This instru ment is ideal for measuring air velocities with the fan ing no charts or separate tables. Frame is Ma hogany Bakelite. revolutions indicated on the For complete information on above in dial. Available in various struments and others designed for heating, models for a wide range of ventilating and air conditioning, send to air speeds and registration any of the offices listed on the previous page limits. for new Taylor Catalog Number Five. 935 Controls and Instruments GAUOC CO- = S'AvdjiXjjimj^xijuL %uxrtdirifr 'Pmaajum. Qau^xk 44 ' BEAVER STREET NEW PACTOIY IIUEISVIUt PENNSYLVANIA RANCHES * HEWTORX-CHICAOO-PRILAOILPMIA BOSTON CLEVELAND OETEOIT ST. LOUIS HOUSTON - SEATTLE LOS ANOELES MONTH EAL YORK U. S. GAUGES--U. S. Gauges are made in all sizes from 2 to 12 in. inclusive for pressures from 1 lb up to 50,000 lb, and for vacuum. Cases may be cast-iron, cast brass, drawn steel and drawn brass for wall mounting or flush mounting. For severe service long wearing hardened steel or bushed movements may be supplied. For service on Steam Heating Systems-- Steam Gauges . . . Compound Pressure and Vacuum Gauges . . . Retard Gauges . . . Compound Retard Gauges . . . Steam Gauges with Internal Siphons. For Hot Water Heating Systems-- Altitude Gauges . . . Tank-in-Basement Gauges . . . Altitude and Pressure Gauges . . . Combination Altitude Gauges, and (a) Bimetal Thermometers, (b) Glass Tube Thermometers, (c) Vapor Tension Distance Type Thermometers . . . Glass Tube Hot Water Ther mometers. U. S. RECORDING GAUGES--U. S. Recording Gauges are made in 8H, 10 and 12 in. sizes for pressures from 1 lb up to 50,000 lb, and for vacuum. Cases may be cast-iron or cast brass for wall mounting or flush mounting. Pen arms are made of non-corrosive metal. Especially designed clock movements are used. Charts can be furnished for customary time periods. U. S. DIAL THERMOMETERS--U. S. Dial Thermo meters are of the vapor tension type with open scale reading in the central and upper portion of the Scale. Cases may be cast-iron, cast brass, drawn steel or drawn brass for wall mounting or flush mounting. Supplied in all sizes from 2 to 12 in. inclusive, for temperature ranges from --40 F to 800 F. Furnished with rigid connection bulb or with flexible capillary tubing up to 100 ft long. 936 Controls and Instruments White-Rod gers Electric Company New York 1293 Cass Avenue, St.Louis, Mo. Chicago Cleveland Detroit Distributors in Principal Cities Indianapolis Line voltage Ther mostat for Unit Heater and Air Conditioning In stallations. Single speed fan control-cover re moved shoving visible dial. Low Voltage Room Thermostat--an ticipating type. PUT "HYDRAULIC ACTION" TO WORK FOR YOU Around the new and basic principle of Hydraulic Action has been designed an out standing line of temperature and pressure controls to fit every requirement. . Hydraulic action contributes these import ant new features to the field of automatic temperature control: 1. Visible, uniformly calibrated dials. 2. Easily set differential adjustor. 3. Fast acting thermal elements. - 4. Combination controls with indepen dently adjustable switches. High capacity switch--the tremendous force available with Hydraulic Action has resulted in a sturdy switch with Underwriters' approved rating of 25 amp 120 v, 15 amp 240 v( \y2 hp (R.I.) 120-240 v AC. Take advantage of Hydraulic Action on your next installation. Specify White-Rodgers controls. The latest condensed control cata log is awaiting your request. Write for it today! Steam Pressure Control--for safety limit service. Dual Immersion Control--LimitCirculator or Summer-Winter service. Stoker Timers-- with magnetic or warp switch relay. Magnetic gas valve gas actuated. 937 Electric Dia phragm gas valve-- absolutely quiet in operation. I W- American Society of Refrigerating Engineers 37 West 39th Street, New York, N. Y. APPLICATIONS EDITION (Vol. II) of the REFRIGERATING DATA BOOK The refrigerating data BOOK is now an essential tool in the refrigeration and air conditioning indus tries. Editions have been published in 1932, 1934, 1936 and 1938. The new 1940 Edition (Volume II) will be entirely different from any preceding volume. It will consist wholly of practical, how-it-isdone chapters on all the known applica tions of air conditioning and refrigeration. Thus the scope of its usefulness is enormous. The Applications Edition will have a wide and popular appeal. It will carry information of a scientific and popular nature to the scores of industries using refrigeration processes. The 60 chapters will be divided into seven main sections devoted to freezing processses, refrigera tion in processing, industrial air condition ing, industrial refrigeration, commercial refrigeration, comfort air conditioning, and storage refrigeration. If you need facts on the latest practice in anything from locker plants to air conditioning in mines or refrigeration in bread making, this book is the place to find them. REFRIGERATING ENGINEERING coils in refrigeration, refrigeration in res LONG acknowledged the most authori tative periodical in refrigeration, taurants, humidity in refrigeration, and refrigeration service charts. REFRIGERATING ENGINEERING has added steadily to the practical value of CODES AND STANDARDS Tits contents, and its number of readers has grown in proportion. A wide variety of material is presented, all from the view HE A.S.R.E. further contributes to refrigeration progress by its partici pation in establishing codes and standards point of its usefulness to the reader in his in the industry. Among the recent codes own business. Up-to-date and attractive made available are: No. 13--Rating and in appearance and style, this magazine is Testing Air Conditioning Equipment; No. a must for men who keep in touch with all 14--Rating and Testing Mechanical Con that is new and important in refrigeration densing Units;__No. 15--Mechanical Re and air conditioning. frigeration Safety Code; No. lfr--Rating and Testing Self-Contained Air Condition APPLICATION DATA BULLETINS ing Units; No. 17-- Rating and Testing ANE19R3o9AuTtswItNaasnGditnhEgeNaGAdIdPNitPEioLEnICRtoAINTRGIOEFdNuRrIiDGngA TATcRoeedsfertsiignaegrreaDnnrtoinwEkxiinpngapnrWseiopanateraVrtaiColvnoe.osle;rsN. o.O1t8h--er Bulletins which appear regularly in each issue. These bulletins are also available MEMBERSHIP ACTIVITIES, separately at reasonable prices for single copies or quantity orders. The APPLICATION DATA Bulletins tell precisely how refrigeration is used in T is the policy of the A.S.R.E. to treat in I its meetings current subjects touching upon all phases of the art of refrigeration. Membership is in two grades with dues various fields, giving examples and specific from $7.50 or $17.50. Sections hold meet information on the best practice up to date. ings in the following cities: Boston, New These subjects have been covered to date: York, Philadelphia, Detroit, Chicago, Mil refrigeration of locker plants, in fur stor waukee, St. Louis, Los Angeles, and age, of liquids, of apples and pears, blower Baltimore-Washington. To keep apace with progress in refrigeration and air conditioning, read the publications and follow the activities of THE AMERICAN SOCIETY OF REFRIGERATING ENGINEERS 37 West 39th St., New York, N. Y. 938 HEATING SYSTEMS Steam and hot water heating systems with their many parts and accessories are classified according to their specific type of design and the service required. These systems and their component parts include: HEATING SYSTEMS (p. 940-961) Combinations of parts forming steam vapor and vacuum systems and hot water systems. , Technical data on steam heating systems are contained in Chapter 15; hot. water systems in Chapter 17. Other references to heating systems will be found in the Index to the Technical Data Section. BOILERS (p. 962-984) Water tube, fire tube and firebox types; cast iron and steel construction; for coal, coke, gas or oil firing. Technical data on heating boilers are given in Chapter 13. In connection with steam and hot water heating systems various types of radiators and convectors are required. Complete manufacturers references will be found in the Index to Modern Equipment--pages 1065-1088. Technical data is contained in Chapter 14. BURNERS (p. 985-994) Automatic fuel burning equipment suitable for use as an integral part of heating boilers and furnaces, and also for conversion of hand-fired heaters to automatic operation. Technical data are given in Chapter 11. PIPE AND FITTINGS (p. 944-946, 995) Iron, steel, wrought iron, copper, brass--seamless or welded. Technical data will be found in Chapter 18. PUMPS (p. 996-999) For use in conjunction with heating systems, and other purposes in heating, venti lating and air conditioning service; and for handling air, gases, ammonia, brine and other refrigerants. . References to technical data on pumps will be found in the Index to the Technical Data Section. HEATING SPECIALTIES (p. 1000-1012) Feed water devices, pressure and draft regulators, combustion controls, strainers, traps, valves, etc.--all essential for efficient operation of heating equipment. References to technical data on heating specialties may be found in the Index to the Technical Data Section, each indexed under its respective title. Manufacturer's products shown in this division are designed for specific applications. Consult the Index to Modern Equipment for additional products of these manufacturers. 1)39 Healing Systems steam Barnes tjones INCORPO HATED MV 129 Brookside Avenue . Boston, Mass. New< York Office: 101 Park Avenue Barnes and Jones Vapor and Vacuum Systems of Steam Heating; Modulation Valves, Packless Quick Opening Supply Valves; Adjustable Orifice Suppl Valves; Thermostatic Radiator Traps and Cage Units, that provide instant trap repair; Thermostatic Traps for medium and high pressures; Condensators (Boiler Return Traps); Float and Thermostatic Traps; Strainers, Damper Regulators; Gages; Proportionator Systems with Zone Control. Modulation Valves Type K Thermostatic Radiator Traps With non-tarnish- able indicating dial, non-rising stem, re newable disc seat. Tail piece extra heavy to prevent breakage--extralong to facilitate connection to radi ator. Three models: lever handle, wheel handle and lock shield. Size..................... Vl In. Cap. Sq Ft Rad... 30 (8 oz pressure)- Vs In. 60 1 In. 100 We In. 180 Packless Quick Opening Valve Type F The Cage Unit, complete operating unit in itself, carries its own seat of special alloy. Cali brated under actual working pressure at the factory and per manently locked in adjustment. Unit easily and quickly replaced without special tools; lift out old unit and insert a new one. Available in sizes to fit almost any make of trap. Symbol 120 12 m 134 13 14 Inlet Tapping.................... Outlet 1 apptng................. Capacity, Sq Ft C. I. Rad.. '/i. % ioo Vi- 74 400 >v*/.m; y/ rr 400 700 1200 Capacities based'on 1 ^ lb pressure differential. Non-rising stem and renewable disc seat. Large un obstructed passages to prevent trouble from dirt or scale. Furnished with wheel handle only. Condensators For returning water of condensation to boiler from open return line systems in dependently of boiler pressure, without change in operating conditions, air binding, or admitting steam to return side. Simple and rugged in construction; positive in operation. All working parts are of best bronze metal. Float and Thermostatic Traps For use on Unit Heaters, also drips from supply mains and risers and on returns from water "heaters and indirect stacks. Float controlled Drill Type valve governs discharge of water; thermostatically controlled valve allows passage of all of air but prevents passage of steam. Made with % in., 1 in., and 1% in., tappings. Capacities 200 lb to 1200 lb of water per hour at 2 lb pressure differential. Combination float and ther mostatic traps with air and water capacity large enough to take care of the Heavy Duly Type load from the largest vent stacks, dry kiln coils, hot water heaters and other units condensing large quantities of steam at low pressures. Made in 1 Yi in. and 2 in. sizes. Capacities to 5,000 lb of water per hour. 2 lb pressure differential. 940 Healing Systems not water Bell and Gossett Company 3000 Wallace Street Chicago, 111. HOT WATER SYSTEMS AND SPECIALTIES B & G MONOFLO HEATING SYSTEMS A genuine advance in con trolled and economical heat ing is offered by the B & G Monoflo System. In conjunction with forced circulation, the B & G Monoflo Fitting makes possible a thoroughly practical, well balanced single main hot water instal lation. In over 30,000 installations, the B & G Monoflo System has demonstrated its desirability in homes, apartments, factories and institutional build ings. The equipment lends itself ideally to zoning, yet is exceedingly simple in application. EQUIPMENT REQUIRED B & G Booster An electricallydriven centrifugal pump, which me chanically circulates hot water through the system -- distin guished by genuine oil lubrication, patented water-tight seal and precision manufacture throughout. B & G Indirect Water Heater Any one of five B & G Heater types can be in stalled to furnish year around do mestic hot water at smallest pos sible cost. B & G Angle Flo-Control Valve This valve, in stalled in the main, controls circulation of hot B & G Monoflo, Fitting water to radia A correctly engineered fit tors, permitting ting, installed in the main at summer opera radiator connections, which di tion of the In verts water into the radiators. direct Water Its design assures a balanced Heater. It also helps maintain a d_i_strib_u__ti_o_n o__f w...a..t.e..r...w...i.t.h...o..u..t uniform room temperature during' introducing excessive resist- the heating season. ance. . Simplex Relief Valve For boiler protection. See Current B & G Catalog for Complete Engineering Data 941 r Healing Systems %^-*trno,pherio C. A. Dunham Company Administrative and General Offices 450 E. Ohio Street, Chicago, 111. Factories: Marshalltown, Iowa; Michican City, Ind.; Toronto, Canada; London, England C. A. Dunham Co.. Ltd. 1523 Davenport Road, Toronto, Ont., Canada C. A. Dunham Co., Ltd., (Of the United Kingdom) Morden Road, London, S.W. 19' England The accumulated experience of the entire Dunham Organization is put at the disposal of the Heating Ventilating and Air Conditioning Engineer. This cooperation is available for Modernization Work, as well as for new construction in industrial, commercial, housing and other projects. "Dunham Heating Service" in local classified telephone directory in all principal cities. Human comfort is assured in buildings heated by the Dunham Sub-atmospheric Steam Heating System because desirable temperatures are maintained throughout the building by automatic control of both steam temperature and steam volume to meet all weather changes. The system is a simple two-pipe system in which all the essentials of circulation, distribution and control are co-ordinated. Balance of heat input with heat loss from the building resulting from variation of pressure are the fundamentals of the Subatmospheric System. Control of the temperature pf the steam in the radiators is accomplished by controlling the pressure or vacuum of the steam in the supply piping and radiators. The Dunham Sub-atmospheric Sys tem distributes a varying supply of heat equally, automatically and continuously through the heated space. Desirable building temperatures are automatically maintained under varying weather con ditions. A positive continuous circulation is maintained as a fundamental function of the system. This maintains unusually constant temperature levels throughout the building. At a control station which may be located in the boiler room, remote readings of building temperatures and operating conditions may be taken. *The Control is fully automatic. Beginning .with a maximum radiator heatoutput obtained by steam circulation at a pressure of 2 pounds and a temperature of 218 F or more as required, the output is progressively reduced according . to the demands of the weather, by a reduction in the rate of steam admission to the system, which automatically causes a reduction in steam pressure and temperature so that steam may be circulated at varying terntemperatures down to about 133 F. Further reduction in heat-output. is ob tained by partial filling of radiators with sub-atmospheric steam until the point is reached at which the need for heat ceases and the supply of steam is completely shut off. . Measuring Heat^Demand. The de mand for heat is measured by the resis tance thermometer principle. Resistance thermometers measure and indicate tem peratures or temperature changes, they are uniquely sensitive, accurate and long lived, operating without moving parts or wear. Variations in temperature at control points create variations in electrical resis tance in control circuits. The supply of heat is varied with the demand by using these variations in electrical resistance through Wheatstone Bridge circuits to actuate the control valve which governs steam supply. The distribution of the steam supply is automatically maintained under all variations in supply by the coordinated functioning of the Traps, Pump, Differential Controller and Regu lating Orifices at radiator inlets. Can also be installed for manual control. 942 C. A. Dunham Company Heating Systems Sub-Atmospheric Steam The RT (Resistance Thermometer) control equipment, which is an integral part of the System, is available in three models. Model T (which is illustrated) Models RS, TRS and TRST. The Model T for indicating and con trolling steam supply in proportion to the demand as measured by room temperatures, consists of a Panel, a Control Valve and one or more Thermostats. It gives: 1. Temperature control so sensitive that a fraction degree F change at the Thermo stat changes the valve opening a slight amount. 2. Temperature control so stable that the control valve cannot take sudden swings of full opening or closing under automatic control. 3. Thermostat setting at the Panel and not at any other point. 4. Room temperature indication at the Panel. 5. An Operating Guide perma nently attached to the Panel. The MASTER SWITCH with 10 selective stations provides: Automatic Control Stations 1. Day Temperature--Range 68 to 86 F. 2. Night Temperature--Range 50 to 68 F. 3. Clock used when Time Switch is added to automatically switch from Day Temperature to Night Temperature. Semi-Automatic Control Station 4. Remote control of Valve position--Range 0 to 100% open. Manual Control Stations 5. Rapid opening of Control Valve. 6. Rapid closing of Control Valve. Indicating Stations 7. Room temperature--Upper Range 68 to 86 F. 8. Room temperature--Lower Range 50 to 68 F. 9. Valve Position--Range 0 to 100% of full open. 10. "Off" Station--AU control and indicating functions discontinued. Model RS for indicating and controlling steam supply with balance between the demand as measured by the Selector (window thermostat) and supply as measured by the Heat Balancer (heat-rate thermostat) consists of a Panel, a Control Valve, a Selector and a Heat Balancer. Models TRS and TRST for indicating and controlling steam supply in proportion to the demand as measured by room temperatures within the limits established by Heat Bal ancer and Selector, consist of a Panel, a Selector, a Heat Balancer and one or more room , Thermostats. These are the only controls on the market that provide fully automatic control in response to the effect of outside weather and to building heat loss. TWO OTHER OUTSTANDING PRODUCTS f-- A compact, efficient and JesnfieAai&t attractive all purpose Heating and Cooling Unit for the home, store or office. Whether for winter or sum mer service or both the Temperator may be installed with access to outside atmosphere. In winter service this unit may be used with sub-atmospheric heating or with pressure steam or hot water system, providing clean, properly warmed and correctly hu midified air with quiet air movement. In summer service instead of adding heat and humidity it dehumidifies and cools. The change from heating to cooling is made by switching from a boiler connection to a chilled water supply or a refrigerating unit which may be at a remote point. Sav^'fteat System (using gas fuel). A practical, efficient and economical method of residential heating and air con ditioning. May be installed as an air conditioning system, as a vapor radiator system, as a hot water system or a com- binatiofuof. these.:. . 943 Heating Systems Hot Water and Industrial Piping GRINNELL COMPANY* Heating, Industrial and Power Plant Piping, Fittings, Hangers, Valves, Pipe Bending, Welding, Piping Supplies, Etc. ' . Executive Offices: Providence, R. I. ./ Albany, N. Y. Atlanta, Oa. (Plant and Foundry) Auburn, R. I. (Plant and Foundry) M .dBaltimore, Boston, Mass. Buffalo, N. Y. Charlotte, N. C. (Branch) Chicago. III. (Branch) Cincinnati, Ohio Offices, Plants and Branc Cleveland, Ohio (Branch) Columbia. Penna. (Plant) Columbus, Ohio Dallas, Texas (Branch) Detroit, Mich. - Kansas Cm, Mo. ' Long Island Citt, N. Y.' (Branch) Milwaukee, Wo. Minneapolis, Minn. (Branch) Newark, N. J. New Orleans, La. . New Yore, N. Y. Philadelphia, Penna. (Branch) Pittsburgh, Penna. Providence, R. I. (Plant and Foundry Rochester, N. Y. St. Louis, Mo. (Branch) St. Paul, Minn. (Branch) Warren, Ohio (Plant and Foundry) Loe Angeles. Cal. (Branch) GRINNELL COMPANY OF THE PACIFIC Oakland, Cal. (Branch) San Francisco. Cal. (Branch) Seattle. Wash. (Branch) Montreal, Qua. (Brandi) GRINNELL COMPANY OF CANADA, LTD. Vancouver, B. C. (Branch) Toronto. Ont. (Plant and Foundry) Oshawa, Ont. (Foundry) Winnipeg Man *' ..PRODUCTS AND SERVICES-- Complete Service on materials to Specification on Power Plant Piping, Industrial Piping, and Industrial Heating Systems; Prefabricated Pip ing including Pipe Cutting and Threading, Pipe Bends, Welded Headers, Welded and Welding Fit tings, Lap Joints and the Grinnell line of products for Super Power. Grinnell Equiflo Valves For Forced Hot Water Heating Grinnell Equlflo Valves for forced hot water heating systems; Grinnell Adjustable Pipe Hangers and Sup ports; Grinnell Cast Iron and Mal leable Iron Pipe Fittings; Grinnell Malleable Iron Unions; Grinnell Weld ing Fittings; Grinnell Thermoliers (Unit Heaters); Grinnell Thermofin (Convectors); Thermoflex Traps and Heating Specialties. Also. Humidifying Systems; Con stant Level Size' Circulating Systems; Piping for adds and other special materials. Malleable Iron, Brass, Bronze and other' Castings; Brass, Cast Iron, Wrought Iron and Steel Pipe; Seam less Steel Tubing in Iron Pipe Sizes. Valves: Check, Globe, Pressure Re ducing and Regulating, Quick Open ing, Safety and Y. Automatic Sprinkler Systems; Stand Pipes; Underground Supply. Mains; Hydrants; Fire Pumps: Pressure and Gravity Tanks. Grinnell "Junior" Automatic Sprinkler Systems for Basements and other hazardous areas of Dwellings, Small Apartment Buildings, Schools, Churches, Stores, etc. Equiflo Valve The designing of forced circulation hot water heating systems is so simplified by the Grinnell Equiflo Valve that they, can be laid out and installed as easily as Vapor or steam systems. This valve consists of a regular type packless radiator valve with a cartridge or tube made up of a series of orifices and baffles capable of setting up any required frictional resistance. This method of establishing any desired resis-. tance does away with elaborate calcu lation of pipe sizes. Grinnell guarantees perfectly balanced circulation to each and every radiator where these valves are installed throughout the system. Equiflo Data Book sent to interested parties. For Data on Thermoflex Traps and Heating Specialties, see page 1007 944 Grinnell Company, Inc. Healing Systems * p"ping 7HERMOUER Patented ' the grinnell unit heater De Luxe, Industrial and Factory Types-- 125 Lb W.S.P. Thermolier is a ruggedly built unit heater whose efficiency and dependability have been proved by actual performance in field service. Thousands of them are installed in industrial buildings and commercial structures of all types of occupancy. # Thermolier has 14 points of superiority, the most outstanding of which is the internal cooling leg built right into the unit, an exclusive Ther molier feature. See drawing below. Radiation is from brass-finned seamless copper U-tubes rolled into a cast-iron tube sheet. No solder is used for strengthening joints and there are no flat horizontal surfaces to catch dirt. Units may be controlled manually or automatically, singly or in groups. Installation and piping are extremely simple and inexpensive, hence the unit may be moved from one THE THERMOLIER INTERNAL COOLING LEG ACCOMPLISHES A RESULT location to another at small cost if found desirable on account of changes in building or occupancy. The complete line includes 22 Models in DeLuxe Type, and 30 Models each in Industrial and Factory Types. . .. Thermoliers provide maximum distribution of heat without objectionable drafts. Specifications pan--Grinnell special of nigged construction. Motor--heavy duty, oversize, enclosed, moisture-proof. Housing--Art Metal Slate gray finish with chromium tnm on DeLuxe Types. Copper on Industrial Type with rubbed lacquer finish; steel on Factory Type finished in gray duco. Frame--Heavy pressed steel, providing rugged support for motor and fan. Special Features--Adjustable swivel hanger rod couplings; louvers rigid, but easily adjustable: integral cooling leg insuring perfect drainage through one thermostatic trap for pressures up to 25 lb. . For pressures not exceeding 125 lb, a thermostatic trap of proper construction can be used and should be attached directly to the unit. CAPACITIES 60 F Entering Air Temperature--2 lbs Steam Pressure Model Nos. 20 20L 25 25L 30 30L 40 40L 45 45L per Hour 35.000 26,900 40.500 30,900 47.800 35,200 69.400 53.300 81,200 62,600 Model Nos. 50 50L 60 60L 65 65L 70 70L 80 80L Btu per Hour 90,700 67,100 104,800 77,700 129 500 110,100 142,000 117.000 164,600 139,300 Model Nos. 90 90L 100 100L 110 1H7L 140 I40L 160 I80L Btu per Hour 189,200 151,600 234,000 196,000 259,000 211,600 320,000 271,000 368.000 294,000 Data Book cover ing other pressures and temperatures, dimensions and complete installa tion information on application. Address Grinnbll Company, Inc:, 277 West Exchange Street. Providence. R. I. 945 Grinnell Company, Inc. Heating Systems ??ne GRINNELL ADJUSTABLE PIPE HANGERS AND SUPPORTS One of the chief advantages of Grinnell Adjustable Hangers is that they permit adjustment of pipe lines after installation, thus obviating the necessity of turnbuckles or the removal of hangers. Their time and trouble-saving qualities during installation are equally exceptional. Below are shown a few Grinnell Hangers and Supports of par ticular interest to heating engineers. Send for Hanger Catalogue showing complete line. Adjustable Swivel Rings (Patented) These Malleable Iron Adjustable Swivel Rings can be used with Coach Screw Rod or Machine Threaded Rod in connection with practically any type of Ceiling Flange, Expansion Case, Insert, etc. Adjustment of at least 1 in. is secured by turning Swivel Shank. Swivel Shank automatically locks, preventing loosening due to vibration in the pipe line. _ The Split Ring permits adjustment either before or after Ring is closed. A wedge type pin is loosely but inseparably cast into the hinged section for fastening this section after pipe is in place. Fig. No. 104 Stitt Rina Fig. No. m Swivel Pipe RoO Adjustable Swivel Pipe - Rolls (Patented) An adjustable type of pipe roll using a single hanger rod. Swivel Shank allows vertical adjustment and automatically locks, preventing loosening from vibration. CB-Universal Concrete Inserts (Patented) . Made of air furnace malleable iron, in one body size, to take a special removable nut, tapped for % in., % in., % in. or % in. rod as required. Nuts automatically lock by means of V-type teeth on both insert and nuts. flff. no. CB-Univerwi inter GRINNELL WELDING'FITTINGS 90* Elbow, Long Turn Grinnell Welding Fittings are made from^ Seamless Steel Pipe or tubing and possess the same physical characteristics as stan dard, extra strong and q.d. steel pipe or seamless steel pipe of comparable size. They can be used under the same con ditions, pressures and temperatures as the pipe itself. Welding faces for all plain circum ferential Butt Welds are scarfed or beveled to the regulation 45 deg. angle with in. square end on inside of fitting. Angles of bevel other than 45 deg. can be furnished on special orders. " ng Wdding Tee 946 Threaded Outlet Heating Systems steam William S. Haines & Company 12th and Buttonwood Sts., Philadelphia, Pa. Manufacturers of EQUIPMENT FOR VAPOR AND VACUUM HEATING SYSTEMS PRODUCTS--Haines Vento Radiator Traps, Medium Pressure and Blast Type Traps, Combined Float and Thermostatic Traps, Air Eliminators, High Pressure Thermostatic Traps, Boiler Return Traps, Packless Radiator Valves and Modulating Supply Valves. HAINES RADIATOR TRAPS HAINES F & T TRAPS The operating thermo stat in all Haines Traps is a specially con structed Bourdon tube, charged with a volatile fluid and hermetically sealed. It is the expansion and contrac tion of the fluid, under varying tem peratures, that furnishes the operating power. The ther mostatic element is outboard the valve seat closing the valve against the flow This trap is designed for handling large quantities of conden sation such as occur at main line drip points, unit heaters, hot water generators, etc. This trap cannot become air bound as it has a ther mostatically controlled bypass, ft is light enough to be supported in the pipe line. HAINES BOILER RETURN TRAPS HAINES MODULATING VALVES j For vapor and atmospheric heating.sys* terns. Prevents cracked boilers. Assures The seat and carrying member construc tion assures positive leak proof perfor mance. Less than a full turn of the handle com pletely opens or closes the valve. This valve is positive circulation by, venting the air and returning the water of condensation to the boiler irrespective of boiler pressure. Weighted valve . mechanism pre packless and vents wire made in sizes drawing of from H in. to 2 in. Can be fur valves. This trap has no nished with wheel or lever stuffing boxes or packed joints handle or lock- to leak air or shield. water. . All Haines material is ruggedly constructed to assure long life and accurately designed for economical operation. . .. Each device is individually tested, factory adjusted and guaranteed. 947 ______________________________Heating Systems SHtwt?*r Hoffman Specialty Co., Inc. Executive Office 500 Fifth Avenue, New York, N. Y. Main Office and Factory: Waterbury, Conn. Sales Representatives in Principal Cities .' Manufacturers of Adjustable Port Radiator Venting Values, Quick Vents and Air Eliminators for One and Two Pipe Steam and Vacuum Systems; Hoffman Supply Valves, Traps and Basement Specialties foriControlled Heat Systems, Air Conditioner Hoffman-Economy Vacuum and Condensation Pumps, and Hot Water Controlled Heat Equipment. AIR VALVES The Nos. 1, 1A and 40 are used for venting radiators on One and Two Pipe oil or gas automatic fired Steam Systems, and the Nos. 4, 4A, 5, 75 and 75 A are used in conjunction with these valves for venting steam mains, risers and other quick venting service. VACUUM VALVES The Nos. 2, 2A Vacuum Air Valves feature the Hoffman Double Air Lock consisting of the vacuum check and vacuum diaphragm. These valves are for use on coal burning hand or stoker fired One Pipe Vacuum Systems; and for venting ends of steam mains or heating risers, where it is also desired to prevent the return of air into the system, the Nos. 6, 16, 16A, 76 and 76A vents are used. ' HOT WATER CONTROLLED HEAT EQUIPMENT The Hoffman Tempera ture Controller is con nected by capillary tubing to the Outdoor Tempera ture Bulb, and to the Water Temperature Bulb installed in the supply main. Variations in out door and circulating water temperatures are instantly transmitted by these two Bulbs to the Temperature Controller which electric ally opens or doses the Control Valve. The Hoffman Control Valve. Admission of hot water from the boiler into the circu lating system is con trolled by this valve. It is opened- and closed elec trically when actuated by de mands for more or less heat from the Hoffman Temperature Controller. Outdoor Temperature Bulb located on exterior of building Water Tempera ture Bulb The Hoffman Circulator is a centrifugal pump of large capacity, low power con sumption and furnished in all standard sizes. It is installed in the return main and operates continuously except when outdoor, temperature rises above 65 deg. 948 Hoffman Specialty Co., Inc. Heating Systems Steam and Hot Water HOFFMAN CONTROLLED HEAT A Hoffman Controlled Heat System consists of the No. 7 Adjustable Orifice Modulating Valve on the supply end of the radiator, the No. 8-A Thermostatic Trap on the return end and either a Hoffman Differential Loop (for coal-fired installations operating at pressures up to 8 oz), or a Boiler Return Trap where higher pressures are encountered, for returning the condensate to the boiler. ,Vo. 7 Modulating Valve SUPPLY VALVES Besides the No. 7 Adjustable Orifice Modulating Valve the Nos. 37 and 47 series (not illustrated) represent a complete line of Packless Supply Valves that meet the exacting requirements of architects and engineers. THERMOSTATIC TRAPS The line of Bellows Type Thermostatic Traps, with hydraulically formed and tested bellows, consists of the Nos. 17-A, 8-A and 9-A, and are principally used for low pressure steam or vapor systems. These traps have nominal capacities from 200 sq ft up to 700 sq ft of radiation. The Nos. 8-A and 9-A have renewable elements, which combine the thermostat, valve pin and renewable seat into a single unit. The No. 10-A Hoffman Trap, which b equipped with waterhammer proof bellows, 1 in. connection, has a fj0 SA--M in. ' nominal capacity of 2800 sq ft. ', The Nos. 8 and 9 Traps have a thermostatic elemeht consisting of three chambers each having a top and bottom diaphragm. These chambers are all joined together and the complete thermostatic member is housed in a cage and is not attached to the valve body or cap. This allows the thermostatic element and valve pin to be easily removed and replaced without adjustment. These traps range in sizes from in. to 1 in,, are medium pressure traps, and are recommended where pressures up to 50 lb are encountered. The Nos. 20-H and 21-H High Pressure Traps are equipped with waterhammer proof bellows, for use on pressures up to 125 lb. Available in 14. in. to 1 in. connection. DRIP AND HEAVY DUTY TRAPS Where large amounts of condensation are encountered, it is recommended to. use one of the float and thermostatic traps, which are available with'or without the thermostatic element. These traps are available in large capacities and are mainly used for venting and dripping risers, steam mains, unit heaters, blast coils, etc. These traps are made in four different pressure ranges 15 lb, ,30 lb, 60 lb, and 125 lb. No. 60 Series Trap VACUUM AND CONDENSATION PUMPS The Hoffman-Economy line of Vacuum and Condensation Pumps offers a dependable method of economically returning the condensation from larger heating systems to the boi)er. These pumps are made in single and duplex units, for varying capacities and pressures. HOFFMAN SALES AND SERVICE : Hoffman Products are sold and stocked by leading wholesalers of heating and plumbing supplies everywhere. Hoffman representatives are available to assist in selection of suitable equipment for various services. 949 Heating Systems sf*am ILLINOIS ENGINEERING COMPANY General Offices and Factory: Chicago Branches and Representatives in Principal Cities - Illinois Motorized Valves (on and off) Illinois Steam Trap Prevent over heating and fuel waste in large buildings or groups of bui1dings . heated from I one central > power plant. Buildings may be zoned as to occupancy, time, location, exposure and so on. In many installations this valve has paid for itself in one heating season. Illinois Reducing Valve Valve and stem are separate from the bucket and operated only by the bucket at the ex treme top and bottom of travel-- result--valve is always either full Series SO open or light closed. N o wire drawing or cutting of valve and seat which are of Monel metal. In general use on vacuum or low pres sure heating systems. Will reduce to 4 oz pressure from an in itial pressure of 150 lb. The large diaphragm insures sensitive opera tion. Made in both straightway and ex# panded outlet bodies in sizes from z/i in. to 12 in. Master Type Pressure Regulator For exacting re quirements, such as tire and rubber vul- | canizing, chemical Eclipse Spring Controlled Regulating Valve Pit. ill Furnished in either single seated or double seated type as the service conditions re quire, for the control of steam, air or gas. Con trolling spring is >mpletely enclosed, protecting it from dirt "and-rust. Valves are furnished with the proper size diaphragm and the proper length spring to give satisfactory service under all operating conditions. Steam and Oil Separators process pressure control, and wher ever high pressure steam must be ac curately reduced in varying amount to any steady lower pressure not less than 10 lb. It will reduce initial pressure up to 300 lb down to any lower pressure not less than 10 lb, and does not build up pressure on a closed or dead end line. Made of bronze with Monel metal valves and seats. Eclipse steam sepa rators are made in both horizontal and vertical type, and also the special receiver sepa rators for standard or extra heavy pressures. Eclipse oil separators are furnished in the horizontal type and have a removable baffle Vertical Standard plate to facilitate clean Separators ing of baffle and keep ing the separator's effi ciency at the highest point. Write tot Bulletins 950 Healing Systems steam ILLINOIS ENGINEERING COMPANY General Offices and Factory: Chicago Branches and Representatives in Principal Cities Illinois Selective Pressure Control Systems HUnOiS Seiec- live Controller An entirely new and unique method of Steam Circulation Control . . . Heating Systems that set new standards in comfort, economy, simplicity and convenience of operation. Each system is individually engineered to meet the exact requirements. Recorded fuel savings, without sacrifice of ctiogmatfioornt,.' warrant Ask for B'youuller tii.nnve1s6-. . Illinois Combination F & T Traps Unsurpassed for draining ventilating units, unit heaters, and for dripping mains and risers-- wherever it is desira ble quickly to vent air from the main as well as handle the water of condensation in quantity, whether Illinois Flow Control Valves Illinois Thermo Radiator Traps Illinois Thermo Ra diator Traps for vacuum, vapor and low pressure heating sys tems. Has Series G cone type valve. Flushes thoroughly and seats perfectly at all times. Valve and seat are of Nitralloy. The duplex diaphragm is of special phos phor bronze. Scientific design and rugged construction assure flexibility and long life. These diaphragms have withstood over three million strokes on a breakdown test. Made in three sizes in., % in. and 1 in. and in a variety of patterns. Special thermostatic traps can be fur nished for working pressures up to 125 lb. Illinois Modulating Supply Valve Quick-opening, packless. Steam tight on 50 ib pressure. Large diameter of thread spool and ma chine cut threads make valve operation easy. Furnished in a complete line of sizes and patterns. Type I In large installations where process steam or zoning require ments do not permit the vari able control of combustion, and in housingprojectsoron Central Station service, Illinois Flow Control Valves are used. They are of the full floating type, giving complete regulation of steam flow. Furnished for manual, pneumatic or electric operation. Ask for Bulletin 517. Illinois Return Trap Automatic ally returns the condensa tion to the boiler, regard less of pressure on the boiler up to 8 Ib, at the same time ^ discharging the air. Insures positive and complete circulation, and prevents cracked boiler sections. Trap is self-contained, with no external working parts to be misadjusted, tampered with or injured. No stuffing boxes or packed joints, which insures continuous tightness against air or water leakage. Write for Bulletins 951 Healing Systems steam Sarco Company, Inc. 183 Madison Ave., New York, N. Y. ' Branches in Principal Cities SARCO CANADA LIMITED, Federal Bldg.. Toronto, Ont. PRODUCTS--A complete line of Specialities for Vapor, Vacuum and GravitySteam Heating Systems and Control combined with a competent Engineering Service to architects and heating engineers to assist them in providing modern, heating. SARCO RADIATOR TRAPS Sarco Heating Systems are "prestige Systems." The traps and valves are the system as far'as maintenance and cost are concerned. Sarco Type H Traps--Are available in angle, straightway, and corner patterns. The Sarco Thermo static Bellows--made by special machinery, has not been duplicated or even imitated with success. It works efficiently, repeatedly and persistently. It has worked that way for a quarter of a century. Sizes J4 in. to 1 in. Catalog HV-4S. Bellcnes-Packless Valve SARCO RADIATOR VALVES Sarco Packless Valves--Used for one and two pipe heating systems and are truly packless. Steam leaks are impossible. Furnished with round or lever handles or lock shield in angle, straightway, or corner patterns. Sizes 14 in. to 1)4 in. Catalog HV-45. . N-100 Medium Pressure Trap , SARCO N-100 TRAP For high pressure radiators and heating coils in sta tionary and marine service, and for hospital and kitchen equipment. Has full length-protecting, shield and stainless steel valve head and seat. Sizes 34 in. to 1 in. Catalog HV-46. Float-Thermostatic Trap Inverted Bucket Trap SARCO FLOAT-THERMOSTATIC TRAPS For dripping ends of mains and risers, and for stack ot blast heaters, large unit heaters and hot water generators. Automatic thermostatic air vents built in. . Available in six sizes with connections % in. to 2 in. Catalog HV-38. SARCO INVERTED BUCKET TRAPS Are recommended for high pressure unit heaters and sometimes preferred for kitchen and laundry equipment. Strainers are built right into these sturdy traps. Seats and valves are stainless steel and renewable. Ther mostatic air vents can be furnished on the larger sizes. Available in sizes )4 in. to 2 in. for pressures up to 900 lb. Catalog HV-165. 952 Sarco Company, Inc. Heating Systems steam SARCO ALTERNATING RECEIVER . A'-complete line of boiler return traps for vapor sysRteemtusr.ns water of condensation to boiler auto matically, thereby assuring positive return of water under all pressure conditions. Made in six sizes for from 1,500 to 25,000 sq Ft of radiation. Catalog HV-45. SARCO AIR ELIMINATORS # For venting air from vapor systems at one central point in the basement. Available in two sizes: No. 6 for systems up to 2,500 sq ft and No. 12-A for 15,000 sq ft. Both are equipped with float valves to stop water : escaping through the vent and with check valves to prevent ingress of air when system is under vacuum. Catalog HV-45. SARCO SELF-CONTAINED TEMPERATURE REGULATORS Sarco Temperature Regulators are simple, selfoperated valves--the only self-contained units that use the irresistible force of liquid expansion. No stuffing boxes to leak, no auxiliary "power" required; all moving parts are inside the equipment. Here again-- a type and size for every purpose--for steam, gas, oil, water or brine for temperatures ranging' from 0 to 400 F. Catalog HV-52. SARCO ELECTRIC CONTROLS Comprise room thermostats, aquastats, and limit controls for all heating and air conditioning needs; also motor valves for steam, water, brine, or freon. The Sarco Graduator System provides simple me chanical control of building heating, direct by the weather. Catalogs HV-150, HV-156 and HV-12S. SARCO WATER BLENDER AND TEMPERING VALVES For mixing hot and cold water to deliver auto matically water at any desired temperature. Two models are available, type IB for showers, wash basins, etc., and type DB, a tempering valve for use with submerged heating coils or tankless heaters. Catalogs HV-140 and 866. Water Blender Type MB 953 Water Binder Type DB Hialing Systems # Steam Unit Heaters WARREN WEBSTER & COMPANY Pioneers of the Vacuum Syttem of Steam Heating Steam Heating Main Office and Factory: Camden, New Jersey Representatives in over 60 cities-- Consult Your Local Phone Directory UNIT HEATER5 PRODUCTS AND SERVICES Webster Systems of Steam Heating including Vacuum and Type "R" (vapor). Webster Central Control Systems including HYLO and MODERATOR. Modernization of Obsolete and Faulty Heating Systems. Webster System Equipment in cluding Light-Weight Concealed Ra diation (Gravity Convection Heaters^, Webster-Nesbitt Unit Heaters, Radi ator Supply Valves, Metering Orifices, Thermostatic Traps, Drip Traps,' Heavy Duty Traps, Dirt Strainers, Dirt Pockets, Boiler Return Traps, Vent Traps, Damper Regulators, Boiler Protectors, Lift Fittings, Ex pansion Joints, Separating Tanks, Steam and Oil Separators, Steam Vacuum Pump Governors, Air Sepa rating and Receiving Tanks, Gages, Water Accumulators. Webster Series "78" and Series "79" Traps for use at process pressures (10 to 150 lb per $q in.) . WEBSTER SYSTEMS Webster Systems are low pressure, twopipe systems of steam circulation with the addition of accurately-sized metering ori fices at radiator supply connections and, when required, intermediate metering ori fices at points in branch mains. Metering orifices effect even distribution of steam to all parts of the heating system and permit the successful application of a centralized control. Webster Valves are used at sup ply of radiators. Webster Thermostatic Traps prevent flow of steam into return mains when radiators are filled. Webster Drip Traps and Dirt Strainers are used where needed on steam mains. Webster Systems are available for vacuum, open return or "vapor" operation. The Type "R" System corresponds to the so-called Vapor type. Fig. 1 illustrates a typical arrangement of Boiler Return Trap, Vent Trap, etc., when low pressure boiler is the source of steam. WEBSTER CENTRAL CONTROLS These are patented systems for varying the amount of steam to all radiators ac cording to outside temperature. They provide continuous heat delivery with effec tive fractional filling of radiators. The Hylo Systems may be provided for manual control, or if desired, may be semi-automatic by incorporation of inside thermostat or thermostat and. schedule clock. The Moderator Systems employ an automatic Outdoor Thermostat sup plemented by a manual Variator. The latter is used for quick heating-up, night load, and unusual weather or oc cupancy conditions. Use of Webster Central Control Systems results in (1) increased comfort because over-heating and underheating are minimized and (2) lower fuel or steam costs. Fig. /. Conventional arrangement of piping around Webster Basement Equipment for the Webster Type "R" System 954 Fig . Webster System Radiation Warren Webster & Company Heating Systems VZffHeate,* WEBSTER SYSTEM RADIATION Concealed, non-ferrous type for use - '\sively with Improved Webster Sys tems ' Is unique in that it combines tn a siniWunil, a light-weight heating element of high efficiency with an orificed radiator supply valve, a radiator trap and supply and return piping connections. Meta enclosures for installation within the wall and exposed metal cabinets are available. Webster System Radiation and enclosures are so designed that the entire heating element can be quickly removed without damage to plaster or paint. Space require ments reduced to a minimum and instal lation greatly simplified. Pressures -- Webster Valves are for use where boiler pres sures do not generally ex ceed 2 lb per sq in. They will not be detrimental ly affected by occasional higher presT sure. Fig. 4. Webster Sylphon Packless Valve radiator supply valves The new Webster Se ries 600 and Series 600S are supply valves of highest quali ty designed to eliminate the many sources of an noyances caused by valves of in ferior design Fig. S. Webster Type "WB" Valve and quality. Webster Sup ply Valves open quickly and easily in less than a turn of the handle. They have non rising stems. Steam can actually be shut off from radiators because they seat posi tively. Extra years of service with little maintenance are assured. Type "WB" Valve (Series 600)--Uses a molded ring packing but may almost be called "permanently packed" as the pack ing seldom requires renewing. A feature is the spring-retained, metal-to-metal seal giving extra protection against leakage. Standard models have screwed packing gland. Modulation sleeve furnished on special order at slight added cost.- . Sylphon Packless Valve (Series 600S) --Same features as Type "WB" except for genuine seamless Sylphon Bellows to com pletely encase valve stem. Meets fully "bellows packless" specifications. Modu lation sleeve is standard equipment for 34r % and 1 inch sizes. Bodies and Handles--Angle Body is made in 34, 1, 134 and 134 inch sizes; right corner, left corner, straightway (both single and double union) bodies in 94 and 1 inch sizes.. The 94 in. size is available with 34 in. spud also. Choice of wheel, lever, lockshield, chain wheel, and extended stem handles. Fig. 5. Metering Orifice Inserted in Union Connection of a Webster Supply Valve Metering Orifices--Accurately sized and made of heavy gage Monel Metal to resist erosion and corrosion, amply thick to be free from vibration and shaped for quiet operation. Available in a number of types to fit both new and installed radiator supply valves of Webster or other make. RETURN TRAPS Sylphon-- Perfected thermostat ic bellows trap, fully compensat ed for pres sure. Stain less steel valve piece and renew able seat.. Fig. 6. Webster SOI Sylphon Trap Factory ad justed. Made in angle, right-corner, leftcorner, vertical and straightway bodies. Sizes: A, Vi and 1 in. Normal operating pressures up to 15 lb per sq in. Maximum occasional pressure 25 lb per sq in. 955 Warren Webster & Company Healing Systems Series "7MM -- Perfected diaphragm- type ther mostatic trap, fully compensat ed for pres sure. Uses Monel Metal dia- Fig. 7. Webster Site 70S-M Trap phragm, Stainless Steel valve piece and seat insert. Renewable seat. Factory adjusted. Made in angle, right-corner, left-corner, vertical and straightway bodies. Sizes: K and 1 in. Normal operating pressure up to 25 lb per sq in.; maximum occasional pressure 50 lb per sq in. Series 7 with phosphor-bronze dia phragm can be used where normal opera ting pressures do not exceed 15 lb per sq in. piece and seat insert. Angle model only. Sizes: % and 1 in. Extensively used with laundry, cooking, sterilizing and other process-steaiti uses. 8 Series "79"--For use where large volumes of very hot condensate form more quickly than can be discharged by thermo, static traps alone. Float and thermostatic traps designed for normal working pres sures between 15 and 150 lb per sq in. Water of condensation is passed through a float-controlled seat opening while air is discharged into the return piping by a thermostatically controlled vent. Com pact and light in weight. Can be readily mounted in a pipe line without other support. Available with either % in. or 1 in. inlet and outlet. Cast iron body, copper asbestos gasket and cover bolted together with steel cap screws. Monel Metal valve piece and stem. Stainless steel seat. Air vent unit is Monel Metal diaphragm with Stainless Steel valve piece and brass seat with Stainless Steel insert. DIRT STRAINERS AND POCKETS Placed in return lines of steam heating systems to prevent dirt, rust and scale from impairing tightness of traps. Fig. S. The Webster Site 0086-T Drip Trap is Rated 7001b teeter per Hour at 8 lb Pressure Difference Series "26"--A heavy duty trap for drips of mains, blast radiation, unit heaters, hot water generators and similar applications. A rugged float-type trap available with and without thermostatic air vent. Made in six sizes: 200, 700, 1200, 2400, 5000 and 11,700 lb water per hour at 2 lb pressure difference. Maximum * working pressure is 15 lb per sq in. Series "78" -- thermostatic trap built for process steam pressures (10 to 150 lb per sq in.). Monel Metal d i a phragm. Stain less Steel valve Fig. 9. Webster Size 788 Trap Fig. 10. Site S4C-1 Webster Boiler Protector with Low Water Electrical Cut-out Switch. Site 54 bos no Cut-out Switch BOILER PROTECTOR Prevents breakage in low pressure heating boilers when water level becomes inadequate. Automatically supplies raw water to boiler when water level drops to 1 in. above bottom of gage glass. For maximum boiler pressure of 15 lb per sq in. Maximum cold water main pressure should not exceed 150 lb per sq in.; minimum must not be less than 25 lb per sq.in. Made with % in. connections, with or without electrical cut-out switch. 956 Warren Webster & Company_________ WEBSTER-NESBITT UNIT HEATERS Are manufactured by John J. Nesbitt, Inc Holmesburg, Philadelphia, Pa., and "ecU-Vibuted solely through Warren Web- ste? or Company, Camden, New Jersey. rThey are designed to circulate large volumes of air at comparatively low temperatures. The heated air is mixed thoroughly with the room air to reduce overheating in upper areas and tempera ture stratification, and to assure quick . . __ f.iol oaci-c ann rnmnlefce Heating Systems Unit Heaters All ratings of Webster-Nesbitt Unit Heaters are based on tests made in accord ance with the standard test code of Industrial Unit Heater Association and A.S.H.V.E. GIANT UNIT HEATERS Centrifugal-fan Type for the economi cal heating of large areas. Floor-mounted, wall-mounted, horizontal-suspended and inverted types; in sizes and capacities, from 3330 to 16,000 cfm, and from 125,000 to 1,008,000 Btu, with 2 lb steam, 60 deg entering air. With or without Thermadjust Temperature Control Damper which pre vents overheating and stratification, and effects fuel savings. Also available with Nesbitt Steam-distributing Tube Heating Surface for installations employing modu lating steam valve control. Send for catalog W-N 104. Fig. 12. Webster-NesbiU Unit Heater, Propeller-fan Type . PROPELLER-FAN unit heaters Seven unit sizes--air capacities, at maximum (an speed, from 495 cfm to 4580 cfm. Three types of heating element for each size, affording wide range of final temperatures and permitting flexibility in selection. Modern casing of heavy furni ture steel, die-formed and welded, rounded corners, black featherweave finish, stain less steel trim. AU-copper heating ele ment of tube-and-fin construction, guar anteed for working steam pressures up to 150 lbs gauge. Steam and return headers of heavy seamless steel tubing. Freedom for expansion, because heating assembly is held in casing by snugly fitted angle guides. Center steam and return connections permit four smaller units to be suspended direct from steam piping. Quiet fans of four-blade type; four smaller units have extra wide overlapping blades for especially quiet service. Rub ber-mounted motors; and Adjustable discharge louvres. Send for Catalog W-N 100. SERIES F UNIT HEATERS _ Centrifugal-fan units for quiet and efficient circulation of heated air in offices, stores, showrooms, restaurants, halls, vesti bules, etc. Four casing sizes, each with two radiator sizes; capacities (60 deg entering air; 2 lb steam) from 94 sq ft EDR to 423 sq ft EDR; 282 cfm to 1355 cfm. Send for Publication W-N 105. RESIDENCE CONDITIONERS Webster-Nesbitt Residence Comfort Conditioning Units, for heating, humidi fying, filtering, and summer cooling with chilled water. Capacities up to 4000 cfm standard air. Send for Publication W-N 107. 957 Heating Systems Boner compounds The Vineo Company, Inc. 305 East 45th Street New York, N. Y. VINCO BOILER CLEANSER A positively harmless insoluble powder cleaner for new, remodeled and old heating systems. A unique, scientifically processed compound on a special formula not to be confused with other powder boiler cleaners. ^snnEsyons jSWlNGSTSW What Vinco Does Vinco removes oil, grease, scale, rust and dirt from the internal surfaces and from the boiler water without the labor of blowing boilers over the top. < . By this thorough cleansing Vinco stops foaming, priming, surging, and slow steaming. * Boiler Cleanser S, 6, and 10 lb cans. How Vinco Works Each minute grain of Vinco powder adsorbs several times its own weight of oil, rust and dirt. These larger grains of adsorbed impurities then settle and are drained through the bottom, according to directions on each can. Our Three-Fold Guarantee X. Vinco contains no potash, iye, soda of any kind, oil, acid, or other harmful ingredients. 2. Purchase price is refunded if results are not as claimed when Vinco has been used according to directions. 3. Your time, money and comfort are further safeguarded by Our Free Laboratory Service It saves thousands of dollars by analyzing the boiler water before making needless mechanical changes. If desired, the boiler water is again examined after the Vinco treatment is completed, and "certified chemically correct" for boiler operation. VINCO SUPERFINE LIQUID BOILER SEAL A different liquid seal. Unique in that it does not induce priming and foaming. It has no unpleasant smell. Makes speedy and permanent repairs of boiler and heating system leaks. Fine to tighten up new jobs. Directions simple. Liquid Boiler Seal 1 qt. cans only Quantities Steam and Vapor Systems--Use 1 quart Vinco Liquid Boiler Seal to each 6 sq ft grate area. Hot Water Systems --Use 2 quarts Vinco Liquid Boiler Seal to each 6 sq ft grate area. VINCO SOOT-OFF Soot-Off 1 lb cans only. Non-explosive, thor oughly safe. No black smoke--no fire hazards. Destroys soot from coal, oil or gas burning heating equipment. Easier, clean er, quicker and more thorough than brushing. Cleans fire pot, flues and chimney in one simple operation. Ask for your copy of the Vinco Manual on the routine care of heating systems. 958 The Vinco Company, Inc. Healing Systems Boner compounds VINCO SPECIFICATIONS insist that Vinco be Used--Correctly--in Every Heating System You <T\ ' . __ Specify or Operate. mi. fused bv the Following Boiler Manufacturers on All Their Boilers) T rive Prop^ Specifi^tions for Cleaning All New, Remedied and Old Steam, Vapor, and Hot Water Heating Systems. /yiERJCAN pADIATOR COMPANY GILBERT 4 BARKER MANUFACTURING CO. International Heater Company JitrJirusvnufnonYfamapHPAHY (Face of Tag) RichmondRadiatorCo. WATERFILM BOILERS (Reverse of Tag) QUANTITIES OF VINCO (IN POUNDS) REQUIRED FOR HEATING SYSTEMS DIRECTIONS TOR CLEANING After the system I* tested ami tight, use the proper quantity of VtNCO listed on the reverse side of this teg and follow directions given on each can of VINCO. Satisfactory results will be obtained in record time with minimum expense. - Vinco also specified by other boiler. manufacturers. .' {In the case of steam heating systems, never blow a boiler under pressure.) ----------"TvT 351 " 400 "" " 401 ** 1100 - " " 1101 " 1400 - - - - ______ _ -5avi " _______ s-------------.4 " _________ to------------------ - s 1401 " 1000 - - - - --13---------------4Vi _ __ Ittl " 2100 - - - - 15----------- -- TVa 2101 " 2700 - - - - _________IS------------------7 2701 * 3100 " - 3101 " 3700 - - 3701 " 4200 " - " 4201 " 4400 - - 4401 " 5000 - - - 5001 " 5300 " " " 5301 " 5400 " - " 5401 " 5900 - - - - ____ ____ a------------------ to - _________*3----------------V* - ________ 2s--:---------- u - ________ 20------------------ M - _________ 30-------- l.-------- IS - _________ J115V - ____ ____ 33U - 33-------------14V* 5901 " 4200 " " " 4201 " 4500 - - " - ________ 35-------------------ITVi 4501 * 4000 - - " - ________ 34------------------ to . 4001 " 7100 " * " " _________ 37----------------- HVi 7101 " 7400 - - - - ________ 30_____ :--------- it 7401 " 7700 " " " - ________ 37-____ :--------- ITVt 7701 " 0000 - - - - ________ o--:-----------------2o ' U01 " 0300 " ' - ________ 41----------------- WVi 0301 - 0400 * " " - ________ 4Z------------------21 0401 " OfOO - " " "43.---------------------------------71 Vi 0901 " 200 - - - - ________ 44__________ --22 7201 " 7500 - " ' " _________ 45----------------- 22Vi 7501 " 7000 " " " " _________ 44----------------- 23 7001 "10100** " " " _________47----------------- 23Vi *Above 10100 m. (Low nilililinniil pnimt **inn *------ * -j.fi!--.j 300 sq. ft. e( Med inrtoBtd rafitfSoe. '' VINCO FOR OLD SYSTEMS Annual cleaning ol the old heating prevents rust deterioration and saves much system adds years of life to the boiler, fuel and fire attendance. 959 *! i Heating Systems Boner Feeders ftFDONNELL & MILLER Manufacturers of McDONNELL Boiler Water Level CONTROLS General offices: Wrigley Building, Chicago, 111. "Doing thing vteU PRODUCTS: Boiler Water Feeders; Combined Boiler Water Feeders and Low Water Cut-offs; Low Water Cut-offs; Com bined Low Water Cut-offs and Pres sure Controls; Electric Water Valves; Pump Controls; Low Water Alarms; Constant Level Valves; Humidifier Water Valves; and related equip ment. Boiler Water Feeders--McDonnell Boiler Water Feeders (Nos. 47, 147, 51, 53 and 101) supply water to boilers when ever the boiler water level tends to drop to the danger zone. Their dependable operation is assured by the McDon nell "Cool Feed Valve"( Patent No. 1,934,486) which prevents lime and scale formation--by packless (bel lows) construc No. 47-2 Com bined Feeder and tion; stainless steel valves; Lem Water Cut the M c - off with "Quick- Hook-Ut>" for automatically fired boilers Donnell "Quick-Hook-Up" below 6.000 sq ft capacity. (Patent No. 1,997, No. 47for handfired boilers in swoimnee ruarnixgee- iws iHd*enntticvual except for the No. t cut-off 785); built-in strainer a nd, many oth. er switch (See below). refinements fully described in the Mc Donnell literature. Feeders and Cut-offs Com bined--Nos. 47-2, 147-2, 51-2 and 53-2 for automatically fired boilers, are the Nos. 47, 51 and 53 with the McDonnell No. 2 Switch as illus No.61-2 Combined trated . In these Feeder and Low Water Cut-off for automat ically fired boilers above combinations the feeder takes care of 6,000 sq ft capacity. No. all normal opera 61, for handfired boilers, is the same except for No. 2 switch. No. 58 and No. tion, and the switch stands by to cut off 68-2 are similar in appear the burner, if an ance but' of heavier con struction for higher pres emergency should sures (See tables l and ). arise such as ex- treme priming or foaming or failure of water supply. Another type of feeder cut-off combination meeting special No. 2 Low Water Cut-off conditions is found Switch used on Nos. 47, 117 in the No. 67 with No. 101, as ex plained under the illustrations at the right. 61 and 58 Safety Feeders. Has high voltage cut-off con tacts and low voltage alarm contacts. Can be furnished on feeders or installed easily after feeders are in place on boilers. Low Water Cut-offs--The No. 67 takes care of all cut-off requirements for boilers with steam pressures up to 25 lb. Its operation is restricted to stop ping the burner when low water threatens the boil er. However it is furnished with an extra switch, as explained under 67--ad- the illustration, vanced de- tor operating the vdopment tn xNto. i1r0v1i cEmlecit. ric low water cut-off with Feeder so that the McDonnell Quick-Hoak-Vp. feeder added at manayy\ti-mbee HonassmexatlrladsrwopitchofwwhaictehrdUosnees, without cutting off burner, to Without Prcomplete circuit to No. 101 rwtr!f-v Electric Water Feeder (See For Lboimlers ., With pressures from 25 lb up to 150 lb, the \MmcDfxonne|l,l xNto. No. 101). Note deep sedimenl chamber, removable clean out plate, and tapping vhieh provides for No. IS Wtreless Pressure Ltmti control. 150 is the cut-off to use. It can be used as either a low watercut-off, a pump control, a low water alarm, or for any com bination of these three tunctions. Service recommendations covering Mc Donnell Boiler Feeders, Low Water Cut offs and Feeder Cut-off Combinations are given in the table at the top of the opposite page which is followed by typical specifi cations. If there is any question as to the proper equipment or hook-up for handling a given condition, our engineering depart ment will be glad to work with you in helping you to arrive at the best solution to your particular problem. Complete installation instructions are packed with each McDonnell product. 960 McDonnell & Miller Heating Systems Boiler Fenders SERVICE RECOMMENDATIONS No. 47 Water Feeder No. 147 Water Feeder No. 51 Water Feeder No. 53 Water Feeder No. 150 as a pump control . Table 2--For Automatically Fired Jobs Water Feeder--Low Water Cut-off Combinations Up to 5.000 Up to 5.000 Up to 5.000 Above 5.000 Any Any iize Under 25 U> 35 lb 25 lb 35 lb 75 lb 1501b No. 47-2 Feeder-Cut-off Combination No. 147-2 Feeder-Cut-off Combination No. 67-101 Electric Feeder- Cut-off Combination No. 51-2 Feeder-Cut-off Combination No. 53-2 Feeder-Cutoff Combination No. 150 as pump control and Cut-off Table 3--Low Water Cut-offs Any size Any size n25 No. 67 Low Water Cut-off (50 No. 150 Low Water Cut-off *If job is hand fired, insert: "No. 47," "No. 147," "No. 51," or "No. 53," as indi cated by service conditions in Table 1. *If job is automatically fired, insert: "No. 47-2," "No. 147-2," "No. 51-2" or "No. 53-2," as indicated by service con ditions in Table 2. When combined units No. 47-2, No. 147-2, No. 51-2 or No. 53-2 are specified, add the following paragraph to specifications: `Make electrical connections for low water switch to control fuel supply equipment, so that the fuel is automatically shut off by the low boiler water control. Control __ wiring to be of No. I0I mtclric flexible armored Water Feederfor cable. All wiring *** w.ih,No-67 to meet the re- Note also quirements of that many mod- the ca1l CTInitsy*p_E_e_l_ec.tciotr,,ni- untis have built-in McDonneii iferw Water Cut-offs which Department and may be used to operate No. 101. the National The No. 101 has stainless steel ,, j nt r-f valve, positive powerful closure oar a OJ r t ft agai^i watcr pressure up to Underwriters. 1601b. Low Water Cut-off--Pressure Control Combination Any size Off at 3 lb No. 67-13 Combined Cut-08 On at 1 lb and Pressure Control Typical Specifica tions for Low Water Cut-off Typical Specifications for Boiler Water Feeder or Combined Feeder and Cut-off Furnish and install complete in every essential detail for each boiler unit. Auto matic Boiler Water Feeder--and Low Water Cut-off (if automatically fired)-- equipment as manufactured by McDonnell & Miller, Wrigley Bldg., Chicago. Boiler Water Feeder to be (insert*) of the manufacturer's most improved-design, with all working parts isolated from the steam and hot water 2one by packless sylphon construction. Float power to be multiplied through a leverage mechanism which contains a self-centering roJler di rectly above valve stem. All bearing points, pivots, and levers to be outside of the steam and water zone. Valve cone and seat to be stainless steel, removable and renewable. A strainer to be incorporated in the design and to have a solderless bas ket mounted on a flange for easy removal. Feeder to be installed complete with all piping, valves, fittings, and specialties, as indicated by descriptive diagram in the manufacturer's construction bulletin. Upon completion of the installation, the contractor to place this automatic equip ment in successful operation, subject to acceptance and approval of the architect's .....................................................engineer. Furnish and install on each boiler in accord ance with the _ ... , , _m__a__n_u__f_a__c_t_u__r_eNroS. IS Pressure Limit Control fqr quick and easy mounting on i. nstructions, #o. $7 Lena Water Cut-off. Its a McDonnell &(insMeirltle*x)rxiLNoow. Water Cut-off plunger forces down the float of the low water cut-off when ex- cess Pressure develops, stopping the burner until proper opera- n'n? pressure is restored. No *to-* be float opera-' wiring. May be used on "built-in" cut-offs which pro tea and to have vide tapping for it. packless con struction. Control wiring to be of flexible armored ca ble. All wiring to meet the requirements of the City Elec trical Inspection Depart ment and the National Board of Fire Underwriters. 160 Combina tion Low flnsert at this point "No. 67" or "No. WaierCutoff. Pump 150" as indicated by service conditions in Table 3. ,, Literature contains Control and Low Water Alarm built to stand up in high Pres sure service. Float operates two switches. One closes pump cir compiete descrip cuit when water level falls; the tions, capacity other cuts burner circuit, and chart, installation completes alarm circuit when instructions, wiring water level falls to danger tone.. diagrams, dimen Maximum steam pressure, 160 sions, etc. " lb. ' 961 1 I Heating Systems Boners, Cest-iron American p <$tandaxd Radiator & aiiftai CORPORATION New York Pittsburgh There's a Complete Line of IDEAL BOILERS For All Needs IDEAL ARCOFLAME BOILER-BURNER UNIT No. 11 Completely coordi nated for average size homes. Boiler and Burner are matched and balanced for effi ciency and economy. Year round hot water supplied by Bilt-in Taco, Heater with Taco-Abbott System. Ratings: Steam instal led radiation 355-755 sq ft EDR; water in stalled radiation 570-1205 sq ft EDR. IDEAL ARCOFIRE STOKER BOILER 2840 sq ft EDR. Specially designed to coordinate with any standard stoker. It's unique "diving flue" deflects fly-ash into settling chamber. Keeps flues cleaner, ef ficiency up, and oper ating costs down. Ratings: Steam instal led radiation 900-1775 sq ft EDR; water in stalled radiation 1440 No. 7 IDEAL BOILER FOR COAL (Stoker or hand-fired), OIL OR GAS Combines fine quality and low cost. Long flues, ground iron-toiron contacts, heavy insulation and many other features. Year round hot water on automatically fired boilers supplied by Bilt-in Taco Heater with Taco-Abbott Sys tem. Ratings: Steam installed radiation 225-750 sq ft EDR; water installed radi ation 360-1200 sq ft EDR. IDEAL REDFLASH BOILERS A popular boiler for any size building. Multiple Asbestocel in sulation. Automatic damper regulator on all steam boilers and on two smallest size hot water boilers. Ratings: Steam installed radi ation 220-6970_sq ft EDR; water installed radiation 350-11,150 sq ft EDR. . 0 IDEAL BOILER No. 92 For automatic oil or stokerfired coal operation in large homes, apartments, stores, etc. Ratings: Steam instal led radiation 1360-2460 sq ft EDR; water installed rad. 2180-3940 sq ft EDR. ARCOFLAME OIL BURNER Quiet, efficient, economical. The special Turbometer effects complete mixture of air and oil--produces a hot, clean "sunflower" flame. IDEAL WATER TUBE BOILERS For large buildings and com mercial installations. Five sizes 23 in. to 79 in. Ratings: Steam 450-15,000 sq ft EDR; water 720-24,000 sq ft EDR. 962 Heating Systems 5oi7ers, Cast-Iron and Radiators radiators, convectors, water heaters and ACCESSORIES RADIATORS /''Wrican Radiator & Standard Sanitary Corporation manufactures a complete line of - rtist iron and copper radiators and convectors suitable for all types of heating. Below `shown part of the complete line. Additional information, complete ratings, dimensions and descriptions will be sent on request. Carlo Radiator Arco Convectors Carlo Hospital Type Perfection Pin (for indirect heating) Peerless Wall Radiator WATER HEATERS Vento (for fan and blower work) ARCO WROUGHT COPPER FITTINGS AND PIPE Both Arco Pipe and Fittings are made of pure wrought copper. Nonporous, they have a smooth inside bore free from butts. The Arco copper-tocopper sweated connection is corrosion resistant and safe against strains, shocks and vibration. It is stronger than the pipe itself. There's a full range of Arco Fittings and Pipe from l/i in. to 4 in. Write for the Arco Copper Manual. There's a complete line of American water heaters. Capacities range from the 3000 gal Arco High Test Tank Heater down to the 65 gal Dome Type Heater shown at the right. Other types include: "Old Line Ideal," Scuttle-a-Day, and Excelso Indirect Heater. ARCO ACCESSORIES Arco Accessories permit the instal lation of completely integrated heating systems backed by a single responsibility. Illustrated are a few of the complete line of valves, vents, and controls. No. 861 Arco Detroit Hurivent No. S001 Equalrol No. SOO Arco Detroit Multiport No. 999 Arco Packless Steam Radiator Valve 963 Heating Systems Z American v> c$1:attdapd Radiator*- CORPORATION New York Pittsburgh GAS-FIRED BOILERS, AIR CONDITIONERS, WATER HEATERS Virtually every automatic gas-fired heating, air conditioning and hot water need can be met with this complete line. There are Boilers, Air Conditioners, Domestic Water Heaters, Convertors, Warm Air Furnaces, Gas-Fired Steam Radiators and others. Full information sent on request. RATINGS--DIMENSIONS--DATA AGP IDEAL BOILERS SERIES H SUNBEAM STEAM BOILER WATER BOILER AIR CONDITIONER Boiler No. AGA "Supplies Steam Installed Rating Radiation Sq Ft Sq Ft Boiler No. AGA "Supplies Installed Water Rating Sq Ft Gravity Sq Ft Accelerated Sq Ft OGS- 4 0-GS- 5 OGS- 6 0-GS- 7 0-GS- 4-E 04SS- 5-E 0-GS- 6-E OGS- 7-E 0-GS- 9-E 0-GS-1 l-E 1-GS- 4 1-GS- 5 1-GS- 6 1-GS- 7 1-GS- 8 1-GS- 9 1-GS-10 i-cs-n 270 360 450 540 255 540 425 510 680 850 610 775 940 1105 1270 1435 1600 1765 * 171 231. 291 357 161 217 275 336 460 592 408 533 666 792 934 1055 1176 1298 I-GA- 4 210 l-CA- 5 280 l -GA- 6 350 l-GA- 7 420 2-CA- 4 420 2-GA- 5 560 2-GA- 6 700 2-GA- 7 840 4-GA- 8 980 4-GA- 9 1120 4-GA-I1 1400 4-GA-I3 1680 1-GW- 4 980, l-GW- 5 1240 l-GW- 6 1500 l-CW- 7 1770 l-GW- 8 2030 l-CW- 9 2300 l-GW-10 2560 l-GW-11 2820 (26 167 210 253 253 342 434 527 624 724 931 1149 624 810 1007 1222 1410 1597 1778 1958 131 . 175 220 265 265 * 359 455, 554 656 761 980 1215 656 853 1063 1294 1493 1691 1882 2074 Larger sizes available. Selection factors for piping loss and starting load al lowances are those recommended by the American Gas Association. Hot Water ratings are on 150 Btu per sq ft basis. 964 AGA Ratings Condi tioner No. Input Btu/ Hour Output at Bon net Btu/ Hour 3 BO sit UDh H -3 H -4 H -5 H -6 HV-4 "HV-3 75.000- "60.000 100.000 80.000 125,000 100.000 150.000 120.000 55.000 44.000 75.000 60.000 11,100 695 14.800 930 18.600 1,160 22.100 1,390 8.200 510 11.100 695 800 1.060 1.340 1.600 590 800 570 662 824 896 413 570 Air inlet to HV-4 and HV-3 is vertically into bottom of Fan-motor unit only. AGP WATER HEATERS Water Heater No. Name and Type Size Cal Btu Input 154-S 204-S BuMdget-StUeel 304-S 404-S 203-S 303-S 403-S Clipper-Steel "" a 603-S 755-S 209-A. Dictator-Copper 309-A " u - 409-A " " 755-A 15 20 30 40 20 30 40 60 75 20 30 40 75 16.000 19.000 24.000 24.000 20.000 30.000 30,000 30.000 45,000 17.000 24.000 24.000 45.000 Recov." Gal Per Hour 22.4 26.6 33.6 33.6 23 42 42 42 62.9 23.6 . 33.6 33.6 62.9 *U. S. Gallons raised 60 F. Recovery capacity Imperial Gallons = U. S. Gallon -r 1.2. Conditioned . Space Cii Ft Max, Fan Cfm | at 70 F j Approx. Ship- II ping Wgt. Lb If Heating Systems American r> ^landavd "Radiator & aiutai CORPORATION New York Pittsburgh wJIM WARM AIR FURNACES AND AIR CONDITIONING UNITS There are Sunbeam Air Conditioners for Coal (hand-fired or stoker) Oil or Gas in a complete range of types, sizes and prices. Below are shown a few from the complete line. Full information will be sent on request. SERIES No. 20 (Left) A Coal-Fired Air Conditioner that meets the demand of the average homeowner who wants a moderately priced unit to replace an inefficient furnace. The cast-iron heat ing element and many other features assure long, depend able service at low cost. SERIES No. 5500 (Right) Designed for burning Coal (stoker or hand-fired), or Oil. Although low in cost it includes Sunbeam quality features throughout. The heavy boiler plate heating element is both rivited and' welded as in the Series No. 80. SERIES No. 80 (Above) For Oil or Coal, hand-fired or stoker. An efficient, moderately priced air con ditioner with a sturdy steel heating element. Inner casing prevents heat loss and keeps exterior cabinet cool. A feature of all Sun beam air conditioners. SERIES No. 500 STEEL FURNACE SERIES No. 1100 (Above) A specially designed unit in which both the Air Conditioner and Oil Burner are coordinated and matched for high efficien cy at low operating cost. Heating element is of heavy boiler plate. Available in. six sizes from 101,000 to 331,000 Btu>.per hour at registers. * A low cost steel fur nace with heating element constructed of 8 gage boiler plate steel. Its riveted and welded construction makes it leak-proof. For oil or coal--handfired or stoker. Sunbeam line also includes the No. 8000 Series steel furnace and the No. 1000 Series cast furnace. ' 965 Heating Systems Balers, steei THE BABCOCK Be WILCOX COMPANY 85 Liberty Street Manufacturers of New York, N. Y. Water-Tube Boilers Oil Burners Chain-Grate Stokers - Seamless Steel Tubing and Pipe Branch Offices and Representatives in all Principal Cities Type H Stirling Boiler The Babcock & Wilcox Type H Stirling Boiler is a highly efficient unit built for moderate pressures at moderate prices.... and is designed to occupy minimum floor space and head room for the heating sur face required. This boiler is built in four classes and 36 sizes ranging from 691 to 6225 sq ft of heating surface, and can be designed for operation with any fuel and every method of firing. : The moderate price is due only to the simplicity of design, efficient production methods and superior shop equipment. Heating Surface j Depth of Setting, 1F t. In. Floor to Center of Mud Drum, F t. In. j Floor to Face of Steam Outlet, Ft. In. Floor to Top of Boiler, F t, In. Size of Steam Outlet, In. Width ofSetting Two Single Boiler* Boiler, in 1 Ft. In. Battery o Ft. In. *91 15-2 9?1 * 1152 H-l 1382 1612 I84d * 2071 2304 \ 6-0 7-0 6-0 9-0 10-0 11-0 12-0 13-0 11-0 13-0 15-0 17-0 19-0 21-0 23-0 25-0 -5-2 a * 14-51/2 13-3'/, * "" * * ** 877 17-8 6-0 1163 7-0 1462 H-2 1734 * 2046 * 8-0 9-010-0 233S 11-0 2631 12-0 2924 * 13-0 11-0 13-0 15-0 17-0 19-0 21-0 23-0 25-0 4-9Y. 14-51/2 13-31/, * " " *** 1063 20-2 6-0 1415 7-0 1772 2126 H-3 248C 2835 3183 3544 * * * 8-0 9-0 10-0 11-0 12-0 13-0 389t 14-0 4252 15-0 11-0 13-0 15-0 17-0 19-0 21-0 23-0 25-0 27-0 29-0 4-sy, 14-51/2 13-3'/, * * *** 1245 22-8 6-0 1660 7-0 2073 8-0 2490 9-0 H-4 2905 * KM) 332(1 11-0 3735 12-0 415(1 13-0 4563 14-0 4980 15-0 11-0 13-0 15-0 17-0 19-0 21-0 23-0 25-0 27-0 29-0 4-1V, 14-iif 13-3Vs * * *" Type B Stiriino Boiler with Babcock & Wilcox Chain-Grate Stoker * 5 The advantages of the Babcock & Wilcox Type H Stirling Boiler may be sum marized as follows: Unusual steaming capacity for the floor space and head-room required. * Boilers may be set singly or in battery. Setting heights can be varied to suit 5 any condition of firing. The choice of three locations for gas exit reduces cost of flues and breeching. Distribution baffles make effective all of the heating surface. * - Tube renewal is facilitated by correct 5 * tube spacing, and a tube removal door. Soot blowers can be readily installed to simplify thorough cleaning of all tubes. A superheater can be furnished with out any change in the standard design " or construction. * 6 6 The boiler is supported by a structuralsteel framework entirely independent of the brickwork. 5 Ample provision is made for free movement of parts due to expansion and contraction. A complete table of sizes and dimensions, together with pertinent installation data, is contained in a new bulletin which will 6 6 be sent upon request. Simply ask for Bulletin G-8-C. 966 Heating Systems soi/ers, ca$t-iron . . - Manufacturers of Cast Iron and Welded Steel Boilers, Cast Iron Radiators and Heating Accessories Irvinfiton-on-Hudson, N. Y. 1 Branch Offices Zanesville, Ohio Lancaster. Pa. Pittsburgh, Pa. Zanesville. Ohio Elizabeth, N. J. Geneva. N. Y. Queens Village. N. Y. Boston, Mass. Philadelphia, Pa. Chicago, III. Baltimore. Md. Springfield. Mass. Plants , Elizabeth. N. J-; Lancaster, Pa. Zanesville. Ohio; Geneva. N. Y. Yello-Jockei Boiler (for coal or oil) For large and small homes BOILERS Jacketed--Unjacketed Cast Iron--Steel Hand-fired--Oil-fired Stoker-fired--Gas-fired Round or Square Sectional boil ers for steam, vapor, or water. Water Tube boilers for steam and hot water heating. Tube-type Smokeless boilers for burning soft coal; Three-purpose Welded Steel boilers for heating, for hot water supply and for incineration. Cast Iron DeLuxe Oil Burning Boiler RADIATORS Exposed and Concealed Cast iron radiators that occupy 40 per cent less space than ordinary radiators of same rating. Shorter, lower, narrower. . Can be recessed if desired. In 3-tube, 4, 5, and 6-tube types. ACCESSORIES Vent Valves for radiators Air and Vacuum valves for mains, risers and radiators. Radiator valves in many designs. Unit Heaters--a complete line in modern designs. Burnham-Taco tanks for hot water supply. Flexible Headers for all pur poses. Unit Air Conditioners--for heating and winter air condi tioning. Attic Fans--complete units for cooling of residences. 967 Concealed radiator with Burnham Panel Front Unit Healer Heating Systems Boilers, Cast-IrQn Crane Co. BOILERS, RADIATORS, VALVES, FITTINGS, PIPE, STEAM SPECIALTIES PLUMBING AND HEATING MATERIALS ' General Offices: 836 South Michigan Avenue, Chicago, Illinois Nation-wide Service Through Branches, Wholesalers. Plumbing and Heating Contractors CRANE HEATING EQUIPMENT FOR RESIDENTIAL AND COMMERCIAL BUILDINGS Whether the Cuel is coal, coke, oil or gas, for steam, hot water, or warm air heating, you can get every part of the system from Crane. Because Crane Systems are engi neered to work as a unit, with high ef ficiency in every part, Crane-Equipment helps you design better heating. One undivided responsibility for the entire system, assures important advantages for both you and your client. Crane Co. Heating Systems m Boilers, Cast-Iron AUTOCOAL STOKERS Worm feed stoker with five speeds. All friction points in transmission case; run in oil bath. Tuyeres of chrome alloy iron. Motor has overload'switch. Capacities up to 150 lbs per hour. CONSERVCHL BURNERS Simple, efficient design as sures economical, quiet operation. Fan and twostage pump on single shaft. Made in adjustable leg and flange models. CRANE CAST-IRON RADIATORS Available in regular and slim tube designs in sizes and types for varying struc tural needs. For limited spaces. Crane "Compac" radiators are recommended --free standing or recessed. CRANE No. 10 ALL-FUEL BOILERS Can be installed for manual firing--easily converted for stoker, oil or. gas firing. High base arid removable grate lugs give ample space for stokeror refractory. High efficiency with any fuel. CRANE SUSTAINED HEAT BOILER-BURNER UNITS Crane patented sustained heat principle extracts more heat from fuel. Down-draft construction prevents es cape of gases into flue before their heat has been ab sorbed. Fully insulated. CRANE BASMOR GAS-FIRED BOILERS High efficiency obtained with staggered fin construc tion and special " Butterfly" Bunsen-type burners. Safe --can't backfire. Wide range of sizes; for natural or manufactured gas. CRANE CONVECTOR RADIATORS Attractive, in heavy steel enclosures. May be fully or partially recessed, free standing, wall hung, or with plaster front. Con vectors are sturdy cast-iron. CRANE "COMPAC" RECESSED RADIATORS A distinct advancement in radiator design. Supplied with end tappings for panels with grill, or bottom tappings for panels without grill as illustrated. CRANE SECTIONAL BOILERS For steam or hot water systems in larger homes and buildings. For manual, stoker, oil or gas firing. Controlled water travel and greater ceiling heating sur face assure fast heating at low cost. Insulated jacket optional. CRANE FURNACES Crane furnaces for coal, oil or gas firing include winter air-conditioning with filter ing, heating, humidifying and circulating equipment. Compact, attractively de signed. Engineered for high efficiency. Oil furnace illus trated. 968 CRANE SPEED HEATERS Provide almost instantane ous heat. Copper heating elements designed for maxi mum heat transfer. Quiet, variable speed motor as sures adequate circulation. Adjustable louvers. In ten sizes; with thermostatic or remote control. NEWPORT WINTER AIR CONDITIONING UNIT A ductless unit, recessed in wall and floor. Provides heat, humidification, filter ing and circulation. One or two units are generally suf ficient for average home. For old or new buildings having two-pipe steam or forced circulation hot water. CRANE HEATING CONTROLS Assure dependable auto matic heating. The Crane line includes room thermo stats, primary oil and stoker controls, fan and circulator relays, temperature and pressure limit controls and regulators, furnace tempera ture controls. CRANE HEATING SPECIALTIES Crane offers a complete range of heating accessories for modern systems and for modernizing old systems. This hot water circulator with flow-control valves will improve the heating plant operation and save fuel. 969 Heating Systems Boilers, Steel Fitzgibbons Boiler Company,Inc. Established 1886 General Offices: Architects Bldg., 101 Park Avenue New York, N. Y. Works: OSWEGO. N.Y. Branches and Representatives in Principal Cities PRODUCTS--STEEL HEATING and POWER BOILERS for all fuels and all heating systems. Capacities to meet requirements of any building. Built and rated according to S. H. B. I. Code. --AIR CONDITIONERS for "SplitSystems" and for Direct-Fired installations in residences of all sizes. Direct-Fired Air Conditioners The DIRECTAIRE--The conditioner that has broken the shackles of traditional "hot air furnace" design, providing far greater Efficiency, Ruggedness, Quietness, Fuel Economy, Cleanability. Stream lined jacket in two types. Four sizes--100,000 to 300,000 Btu at the bonnet. The SPECIAL 80-120 DIRECTAIRE--Designed and priced, without sacrifice in quality, for the small home budget. Already in successful use in scores of housing developments. Two sizes--80,000 to 120,000 Btu at the bonnet. "Split-System" Air Conditioners The FITZGIBBONSAIRE combines with Fitzgibbons Steel Boilers for auto matic firing with oil, gas or stoker, to provide: (1) CONDITIONED AIR (cleaned, humidified, tempered, circulated) to all rooms where desired; (2) RADIATOR HEAT to kitchen, baths, garage and other parts through which recirculation is un desirable; (3) YEAR-'ROUND DOMESTIC HOT WATER, without a storage tank. Steel Heating Boilers The 400 SERIES--A boiler for small home heating that brings steel boiler economy and comfort within the building budget of the low-cost house. Built of welded copper-steel throughout, crack-proof, leak proof, corrosion-resistant, quick-heating. Cooperates with any good oil burner, stoker, gas burner. Gives year-'round domestic hot water, with or without tank. Heavy insulated jacket. Ratings, Steam-- 3 sizes--400 to 680 sq ft. The OIL-EIGHTY AUTOMATIC*--An outstanding residential steel boiler for oil firing. Teams up with any good rotary or gun type burner to form a highly efficient unit. Provides room for burner inside the jacket. Year-'round tankless domestic hot water optional. Ratings, Steam--12 sizes--425 to 2680 sq ft. The GAS-EIGHTY--For gas. Jacketed. Ratings, Steam--12 sizes--425 to 2680 sq ft. The STOKER-EIGHTY--For anthracite and bituminous stokers. Jacketed. Stoker may be installed at either side if desired, to allow free access for inspection through door in front. Supplies year-'round hot water with or without tank as desired. Approved by Anthracite Industries, Inc. Ratings, Steam--6 sizes--485 to 2000 sq ft. Reg. U.S. Pat, Office. 970 Fitzgibbons Boiler Go., Inc. Heating Systems Boilers. steel FITZGIBBONS R-Z-U JUNIOR Multi-Service Steel Boiler RATINGS. STEAM . 'Coal Burning Type........ 900 to 3200 sq ft "'nil Firing Type.............. 1100 to 3900'sq ft V* . T-____ linn onnn f. Outstanding Features Tanksaver (optional) supplies year- 'round hot water without a separate storage tank. Tankheater (optional) a more efficient in direct water heater. Auxiliary Grate (optional), for refuse disposal and stand-by heating duty in oil fired installations. Com pact, largest size will pass thru a 31 in. door way. Low Water Line, eliminates need for a pit. Jacket (optional), on all types. Descriptive Bulletin on Request FITZGIBBONS Z-U Steel Firebox Boilers Built for 15 lb w.s.p.--A.S.M.E. Code. Up-Draft Type..... 1800 to 35,000 sq ft steam R-Z-U FITZGIBBONS R-Z-U Steel Firebox Boilers The Z-U arranged for rear smoke outlet. Built for 15 lb w.s.p.--A.S.M.E. Code. Up-Draft Type..... 1800 to 35,000 sq ft steam Smokeless Type.__1800 to 35,000 sq ft steam Oil, Gas, Stoker...,2190 to 42,500 sq ft steam <8 . FITZGIBBONS "F" SERIES Portable Riveted Firebox Boilers Built for 100 lb w.s.p.--A.S.M.E. Code. Ratings, steam--1800 to 15,000 sq ft 600 Strict FITZGIBBONS 500 SERIES Portable Welded Firebox Boilers-- Return Tubular Built for 15 lb w.s.p.--A.S.M.E. Code Ratings, steam--3500 to 35,000 sq ft FITZGIBBONS 700 AND "P" SERIES Portable Riveted Firebox Boilers 700 Series for 15 lb w.s.p.--A.S.M.E. Code. Ratings, steam--3500 to 35,000 sq It "P" Series for 1001b w.s.p.--A ..S'.MJi. Code. Ratings, horsepower--25 to 250. FITZGIBBONS 600 AND 800 SERIES Smokeless Down-Draft Riveted Firebox Boilers Built for 15 to 100 lb w.s.p.--A.S.M.E. Code. Ratings, steam--3500 to 35,000 sq ft 600 and 800 Strict Descriptive Bulletins on any or all of above boilers will be mailed on request. 971 Heating Systems Boners, steel i Farrar & Trefts Incorporated Buffalo, N. Y. HEATING AND POWER BOILERS Bison Compact Boilers 1 Blsonette Compact Boilers Firebox Return Tubular Boilers Firebox Locomotive Type Boilers Scotch Marine Type Boilers Vertical Boilers Horizontal Return Tubular Boilers Bison Two-Pass Return Tubular Boilers Established 1864 STEEL PLATE CONSTRUCTION Storage and Pressure Tanks' Receivers, Welded or Riveted Steel Pipe, Welded or Riveted * Buoys, Welded or Riveted - . Condensers and Kettles Smokestacks and Breechings Special Work In Stainless Steel, Everdur, Nickel, Aluminum or Monel Metal The F&T Bison Compact Welded Heating Boiler is more than just another boiler. It has been designed carefully so as to have a large furnace volume, the proper volume of water, just the right amount of steam liberating surface, the correct volume for steam storage and a balanced circulation. The result is a remarkably steady water line--A Balanced Boiler. . This, boiler requires a minimum amount of floor space and is easy and inexpensive to install. It is reasonable as to first cost and economical in operation. Construction is in accordance with the A.S.M.E. Code for 15 lb working pressure and boilers are designed for hand firing with anthracite or bituminous coal The Biton Compact or for mechanical firing with oil, gas or stoker. There are various sizes available from 1800 to 35,000 sq ft of steam radiation, all ratings1 as require^! by the Steel Healing Bailer Institute. The Bisonette Compact Boiler has the same characteristics as the larger Bison Compact Boiler. It has been designed for installation.in large residences and small business establishments where the advantages inherent in a Steel boiler are desired. Firebox Return Tubular Heating Boilers are Quality Boilers.- They are constructed to measure up to the high standards set by Heating Engineers and will ^ give unfailing sendee under all ' conditions. Being economical to install and operate, they are highly favored by Architects and Engineers for hqating Schools, Hospitals, etc. . , There are two types of Firebox Boilers, the Up-Draft Type and the Down-Draft Type. Both types are made- of welded or riveted construction for heating purposes at 15 lb working pressure and riveted, or, Class 1 fusion welded x-rayed and stress-relieved for power purposes Firebox Return Tvboiar Boiler at 100, 125 and 150 lb working pressure in accordance . ,, with the A.S.M.E. Code. Sizes from 1800 to 35,000 sq ft of steam radiation, as rated by the Steel Heating Boiler Institute, are designed for hand firing with coal or for mechanical firing with oil, gas or stoker. - The Bison Two-Pass Return Tubular Refractory Lined Boiler is favored by many Engineers because it Eliminates Water Legs, Flat Sides and Staybolts. It has been designed to stand up under heavy loads, is dependable for long years of continuous and economical operation and will provide that surplus of power so often needed. This type of boiler is made of Riveted construction, of Riveted-Welded construction, or, of All Fusion Welded con struction. "the Riveted-Welded boiler eliminates a riveted seam in direct contact with the furnace fire. The All Fusion The Bum TtcoPaee Welded boiler has all seams welded. These boilers are built according to the A.S.M.E. Code for ratings from 25 to 250 hp. They are adaptable for coal and for oil, gas or stoker firing. 972 'id Heating Systems Batters, steel. The International Boiler Works Company East Stroudsburg, Pa. /> "Fuel Saver" Water Tube Steel Heating Boilers ALBANY. .V V. Boston. Mass. Bm'.vto. N. V. Cincinnati. Ohio. Detroit. Mich. Lexington. Ky. Louisville. Ky. SALES OFFICES Missoula, Mont. New Haven. Conn. New York, N. Y. Newark, N. J. North Olmsted. Ohio Philadelphia. Pa. Pittsfield, Mass. Poughkeepsie, N. Y. Rochester, N. Y. Salt Lake City, Utah Scranton. Pa. Springfield, Mass. Syracuse. N. Y. Toronto. Ont. (Canada) Utica, N. Y. White-Plains, N. Y. ' Washington, D, C. Wilmington, Del. International "FUEL SAVER" Water Tube Steel Heating Boilers offer the same quick steaming and economy that have long been accepted as most efficient in marine and industrial service. "FUEL SAVER" Water Tube Boilers are available for large and small heating requirements in a wide range of types and capacities. TYPE C "FUEL-SAVER" WATER TUBE STEEL HEATING BOILERS For Office and Apartment Buildings. Schools, Hotels, Theaters, Institutions and Industrial Plants Built in a complete range of standardized sizes and provide highly efficient performance for heating large buildings. Up-to-date water tube.design permits absorbing.the intense heat released by. modern methods of firing and they will operate efficiently under loads considerably in excess of ratings. is / from 2680 to 42,500 sq ft mechanically fired rating. X from 2200 to 35,000) sq ft hand fired rating. TYPE KD "FUEL-SAVER" WATER TUBE STEEL HEATING BOILERS For Replacement Installations in Large Buildings Eliminates Costly Cutting and Patching Especially designed for renovation and replacement work. Shipped knocked down in standardized parts that can be taken through existing doors or openings to basement and boiler room. International erects or assumes full responsibility for erection work of knocked down boilers. it } 5850 to 56,470 sq ft mechanically fired rating. ' 1 4810 to 46,510 sq ft-hand fired rating. TYPE DD "FUEL-SAVER" WATER TUBE STEEL HEATING BOILERS For Residences, Small Apartments and Other Buildings Highly economical. Superior performance of water tube design usually found only in larger commercial and indus trial installations. Fully utilize intense heat generated by modern automatic`firing devices. Stoker-fired coal and oil most commonly used, with savings often exceeding 20 per cent over previous installations. Stoker-fired boiler tested and approved by-Anthracite Industries Laboratory. A copper coil submerged above the crown furnishes ample hot water for domestic needs. Insulated steel jacketslin two tones 6f gray enamel are included. * in eivAo f 510 to 2550 sq ft net steam rating, ( 816 to 4080 sq ft net hot water, rating TYPE CR "FUEL-SAVER" WATER TUBE STEEL POWER BOILERS For High Pressure Steam Service ' Designed for pressure of 100, 125 and 150 lbs, the Type CR is especially suitable for hospitals, hotels, laundries, dairies, institutions and manu facturing plants requiring process steam. Sizes range from 5 to 300 hp. Data and catalogs on "Fuel-Saver" Boilers will be furnished on request. ' 973 Kewanee Boiler Corp Heating Systems B0uers. st,/ 1 fCeWanee Boiler Corp. Heating Systems * Boner,, steet r Kewanee Boiler Corp. Heating Systems Boilers, Steel 20000 24290 72x184a 107 20000 Ii5j=slJ fS 19 '*> 0 ---<g -- frNwS\ l tN, 8^3r^'CS 9 "o ' 522sb5b S^g^8S < \090 gCritg? sa 53^-^KS IS---- 1 *5 17 | S-xtU! n-- Lw Fz 16K 18K N SSlggli *oeIDo 5! < 88s2^_*<o^.Sss, ****>,$} ^ -- 1I0om00. |0200i<S! 8e|oll 18^--mrtS 9 SaRl= 1 vfi <? 0 SS?s!88 <g >*25gS " r^j SS5- 11; AjC 88 S5.S *SS EJ3--ggs--i "^5 t3f.8S KOtO^m ~S~ -- 9 io k ; an 1 01 U i-- I 1b--nhi a40 r* u Lhi r >* 7 38_Hf*>0gS8v8g u*\ O_ 88^-gg *=K<5'r *0o8 K 8s3t-88 sx.g1"0^! p-ss^i s o 8S5_58g irOAN< y"Q ISw0ivSs mo8*S^r=*K4r_> 5coSoiAr8n^ 2 n88 --"'i0rnft8'rTs'8NT m- - ggl^gg o--o --n>m*\ <o>anS 2 8oAl/m^8$ Soo *"8 gg OCdC * sNtnisKOSCO.rnli >y*Rloido %S 88 Nm-N- 3" I gSc^ gg pw> =2<iS!sS *A " |r< ss^s: 88 1SkD OJ!l>N0>0 -* I5sScsn oogrs8-- 5fS XO'N-C ^883_K:Oc2s>otoN380..8O' ? 088a?ic:fCt5nZ88 * eo oo i* 35 rs < rDo 883^<S8 N^g(Sh>$N s S8S<ysg s- SR8RS <iC>O55rt>*%NNw il==ss orom> oqT----- 00 Si^essg o^j tri isi-l! 9tm>0 ilissif >o*rt rt*-. oS oo05 o OO "7 oo - e--<--s, rur, inin(KA--"' SS?r?5j w--^0K8!8? JTJTt B o ile r N o ..........*........................ B o ile r N o ............... :::: ; :-3 ; h \ :A : j<|S 1 U o gii& a: siaSs &_& s? | %<< x x;Uz. ::. :. ;. . ip. m a_^ ; -- _ u 5'*; 5jS wimi **a >< "8.1 S.ff a C QOX< .3 tii-s iSJsJS-* SS-2IS2 3 3 Sl'j E 52 hz'lbisiifs o oox< 976 Ktwanee Boiler Corp. Heating Systems Boners, steel Heating Systems Bonsteel Pacific Steel Boiler Division United States Radiator Corporation General Offices: Detroit, Michigan Sales Offices in Principal Cities A Complete Line of Low Pressure Steel Heating Boilers All Pacific Boilers are built using the A '.S.M.E. Boiler Code Standards as minimums. LOW WATER LINE SERIES Built in the following capacities for steam: Coal Burning Sizes--1800 to 35,000 sq ft. Mechanically Fired Sizes--2680 to 42,500 sq ft. High Fire Box for Stoker Firing--Sizes-- 2680 to 42,500 sq ft. All Pacific Boilers are built, inspected, and tested under the supervision of the Hartford Steam Boiler Inspection and Insurance Company. TWO-PASS FRONT SMOKE OUTLET Built in the following capacities for steam: Coal Burning Sizes--4000 to 30,000 sq ft. Mechanically Fired Sizes--4860 to 42,500 sq ft. All Pacific Boilers are made of steel with each joint and seam electrically arc-welded --built to last a life-time. SINGLE-PASS REAR SMOKE OUTLET . Built in the following capacities for steam: Coal Burning Sizes--1800 to 6000 sq ft. Mechanically Fired Sizes--2190 to 7290 sq ft. ^ PACIFIC THREE-PIECE CONSTRUCTION Made up of three parts, shell, firebox and base. Pacific Boilers are particularly adapt able to replacement work. Where necessary Pacific fireboxes can be split (as illustrated) allowing the boiler to be taken into the building in four pieces and erected without welding on the job. Descriptive Bulletins on Pacific Steel Boilers will be mailed on request. 978 Heating Systems Boilers, steel Smith Twin Tubular Boiler Co., Inc. State Road and Cottman Street Philadelphia, Pa. MANUFACTURERS STEEL HEATING BOILERS Smith Sectional Steel Boilers have eained favor with Architects and Engineers due to their compact construction and adaptability for installing in boiler rooms of building through existing doom or openings. Built on foundations or f.o.b. shop for coal, stoker or oil firing. Write for circular for Domestic Boilers All the outstanding advantages of both the water tube and fire tube boilers with out complicated baffle construction. Faster steaming and higher efficiency obtained by rapid water circulation due to water tube construction that comprises 50 per cent of the boiler heating surface. specially designed for Oil or Stoker firing. SPECIFICATIONS--SMITH SECTIONAL-STEEL HEATING BOILER Number of Boiler 2-60 2-72 2-84 2-96 2-108 3-84 3-96 3-108 3-120 4-108 4-120 4-132]4-l44 5-132 5-144 5-156 Steam R. (Oil-Stoker)... Heating Surface............. Water Line In................ Floor to Water Tubes In. Furnace Vol Cu Ft....... Length of Shell In. A Width of Shell In. B 4800 285 65 42 51 60 51 5800 343 65 42 63 72 51 6800 401 65 42 75 84 51 7600 458 65 42 86 % 51 8800 525 65 42 100 108 51 10000 11400 12800 14200 16000 589 672 753 835 944 71 71 71 71 78 42 42 42 42 46 93 108 124 139 161 84 % 108 120 108 61 61 61 61 71 17800 19600 21400 1050 1154 1262 78 78 78 46 46 46 181 201 221 120 132 144 71 71 71 24800 27100 1462 1593 85 85 50 50 253 279 132 144 81 81 29300 1724 85 50 304 156 81 Height Bottom Sec. C Height Top Sec. D Length Top Sec. E Length of Boiler In. F Width of Boiler In. C Height of Boiler In. H Height Top Header 1 No. & Size Outlets In... No. & Size of Returns In. Dia. Smoke Collar J Height Stack Ft Length of Pit In. M Width Foundation N Length Foundation O Width Ash Pit K Length Ash Pit L 31 28 60 84 31 28 72 % 31 28 84 108 31 26 96 (20 31 23 108 132 42'/2 2bVz 84 42Vi 261/5 42'/2 26'/2 421/* 231/5 48>/? 30/5 48*/2 30'/2. 48/, 3C/5 481/, 301/5 96 108 120 108 120 132 144 % 132 144 110 122 134 146 136 148 160 172 160 172 156 184 56 72Vi 84 1-8 1-4 20 50 50 56 62 44 50 56 56 56 So 66 66 66 66 76 76 76 76 86 86 72Vi 84 72Vi 84 72Vi 84 72'/z 84 78>/2 90 78'/2 90 78>/2 90 7Wi 90 84i/2 98 84i/2 98 84i/2 98 841/2 92 98 107 92 107 1-8 1-8 1-8 1-8 1-3 1-8 1-8 1 8 1 10 1-10 1-10 1-10 1-10 1-10 1-4 1-4 1-4 1-4 1-4 1-4 M 1-4 1-6 1-6 1-6 1-6 1-6 1-6 20 20 20 20 24 24 24 24 30 30 30 30 36 36 55 60 65 70 65 70 75 80 75 80 65 90 85 90 62 74 86 98 68 80 92 104 92 104 116 128 104 128 56 56 56 56 66 66 66 66 76 76 76 76 86 86 74 86 98 110 86 98 no 122 no 122 134 146 134 146 44 44 44 44 54 54 54 54 64 64 64 64 74 74 50 56 56 62 52 58 64 64 58 64 70 70 64 64 86 92 107 1-10 1-6 36 95 140 86 158 74 70 Steam R. (Hand-Fired).. 4000 4800 5600 6400 7200 8250 9400 10500 11700 13200)14700 16200 17700 20500 22400 24000 Crate Size In................. Crate Size Sq Ft........... 46x48 46x48 46x5^ 153 153 173 46x54 46x60 56x54 56x60 56x66 56x66 66x6066x66 66x72 66x72 173 19.1 21.0 23.3 25.6 25.6 27.5 1 30.0 33.0 33.0 76x66 76x66 34.8 34.8 76x72 37.3 Standard Ratings conforming with the Industries "Simplified Practice Recommendations." Special High-furnace Boilers furnished for Oil Burners or Stokers. 979 Heating Systems Boilers, Cast-Iron Spencer Heater Division Aviation Manufacturing Corporation Williamsport, Pa. Sales Representatives In Principal Cities Spencer Automatic Magazine Feed Heaters are furnished in cast iron sectional types --and steel tubular types for larger buildings--for steam, vapor and hot water heating. There is a size and capacity for every type of building, to provide economical and con venient heat--safe, dependable, sure. COMFORTABLE HEAT AT LOW COST Coal -- Coke -- Gas -- Oil -- Spencer J and L series heaters and M series boilers are primarily designed to burn low cost No. 1 Buckwheat Anthracite or small size coke; the CN series Nut or Pea Anthracite, or Nut size coke. If at any time a property owner desires to burn more expensive fuels--oil.or gas-r-- his Spencer Heater can be readily con verted and will show a high efficiency. Thermostats--Thermostats <and electric damper motors are furnished as optional equipment. Spencer Jacketed Healer L-l Series Why Spencer Heaters perform so satis factorily can best be explained by an inspection of their design and construction. The Spencer principle, illustrated in the cross-sectional view, is simple: Once a day fuel (No. 1 Buckwheat Anthracite or small size by-product coke) is put into.the magazine. It fills the sloping grate to the level of the magazine mouth. The fire bed always stays at the proper level, for as fast as fuel burns to ash, it shrinks and settles on the sloping grate; and more fuel rolls down automatically over the top of the fire bed. Fuel feed is by gravity alone, in just the right amount to keep the fire always burning at its most efficient combustion point. This explains why a Spencer Automatic Magazine Feed Heater always gives the same uniform, satisfying heat, and burns less fuel. These exclusive Spencer ad vantages are available in all types of the magazine feed heaters and boilers. Jacketed Covering--Attractive metal lic jackets of the deluxe enclosing type, as illustrated, are available for Spencer Cast Iron Heaters, either with or without the enclosing jacket doors. ' Spencer Heavy Duty Tank Heaters-- With the automatic magazine feed con struction, they provide ample domestic hot water at lowest cost, and with a minimum of tank heater attention. Cutaway sectional view Spencer Cast Iron Heater 980 ' Spencer Heater Division Heating Systems Boilers, steel SPENCER ALL YEAR SYSTEM . in addition to the excellent heating ' facilities afforded by Spencer Magazine 'Feed Heaters, Year Round Domestic Hot Water Service can also be provided and assures at all times an ample supply of domestic hot water at lowest cost. Com plete data for installation and operation upon request. SPENCER STEEL TUBULAR MAGAZINE FEED BOILERS For large buildings we recommend Spencer Steel Tubular Magazine Feed Boilers, burning low cost No. 1 Buckwheat Anthracite or coke. In the cross-section diagram, part of the fire bed is cut away to show the sloping grates and the two magazines filled with fresh coal, ready to feed down automatically by gravity to the fire. These boilers are built in two vertical sections for ease in handling and installation--a great ad vantage on replacement jobs, eliminating the necessity of costly tearing out of walls or parti tions. Combination water and fire tube con struction; built to A.S.M.E. standards. Tubular Magazine Feed Boiler SPENCER STEEL TUBULAR BOILERS For Oil, Stoker, Gas or Hand-Firing For more than 40 years, Spencer has been building, in the opinion of experts, one of the most efficient, economical and dependable automatic coal burning boilers on the market. With this background of experience, Spencer Engineers developed the Spencer Steel Tubular Boiler, for oil, gas, stoker and hand-firing--the "K" and "C" series for residential use, and the Type "A" for larger buildings. It is a better boiler both for the property owner and for the architect or engineer who specifies it. The high sustained efficiency of these boilers means adequate heat for a lower fuel cost. Design is of the three pass type. Combustion chamber is amply large. Built of best quality open hearth steel boiler plate, and Electrunite tubes. Can be furnished with domestic hot water heating coils, storage tank or instantaneous type. They are better boilers both for the property owners and for the architects or engineers who specify them, and provide a complete range of sizes from 400 sq ft SHBI net steam rating up. They meet or exceed in every particular the require ments of the A.S.M.E. and S.H.B.I. Codes. Every Spencer Boiler is guaranteed to These boilers have all the advantages of carry more than its full rated load, giving the Spencer exclusive design. High sus the installer a definite factor of safety. tained efficiency--low fuel cost. 981 Heating Systems Boilers, Casf-/roj United States Radiator (corporation General OUices: Detroit. Michigan Branches and Sales OUices in Principal Cities Detroit, Michigan CAPITOL RED TOP BOILERS FOR ALL FUELS______ Ratings in Sq Ft Direct Cast Iron Radiator Loads-- Sq Ft "A" Series "B" Series C" Senes Steam-- 575-1450 Water-- 975-2475 Steam--1200-3600 Water--1980-5940 Steam--4700-10.500 Water--7760-17.325 280- 655 460-1085 550-2030 910-3350 1865-5805 3080-9580 ' Illustrated above is a Capitol Red Top Series "C" Boiler. Capitol Red Top Boilers can be furnished with extra high steel bases to provide extra setting height or desired additional furnace volume for stoker firing. CAPITOL RED CAP BOILERS For All Fuels Direct Cast Iron Boiler No. Radiator Loads Sq Ft Steam Water 19-4 300 19-5 350 495 580 20-4 400 20-5 450 660 745 22-4 500 22-5 550 825. 910 25-4 625 25-5 675 1030 1115 Capitol Red Cap Boiler design brings the advantages of (1) long fire travel, (2) flue passages that force the hot gases to circulate through every section, ex tracting the maximum heat from the fuel consumed. (3) Deep firepot that provides the extra space needed for better com bustion, and smooth, tapered firepot walls to assure a clean surface for better heat absorption. CAPITOL SUNRAY BOILER No. I Series Direct Cast Boiler No. . Iron Radiator Loads Sq Ft Water (Oil) 1-03 330 14)4 460 1-05 585 1-06 710 Water (Coal) 1-4 460 1(--65 585 710 CAPITOL SUNRAY RADIATOR Space Saving--Can be fully or partially recessed--Also well adapted for free stand ing installation. Self-contained Cabinet Radiator--de-. signed to form its own enclosure. The "No. 1" Series Capitol Sunray Boiler is furnished in Coal Burning and Oil Burning types. The unusually generous sized combus tion chamber is scientifically proportioned so that it will operate at highest efficiency. The hot gases of combustion are forced with a swirling, scrubbing action directly : against heat-absorbing surfaces. 982 Heating Systems Boilers, Cast-Iron UnTtedStates Radiator (corporation Genera! OUices: Detroit. Michigan Branches and Sales OUices in Principal Cities ^ . Detroit, Michigan ftP _ slies tf F1CI MCI ---- i ^ nirp^t Standing Radiator Load Flue CAPITOL FINCAST ENCLOSURES AND CONVECTORS Made entirely of cast iron. Without joints--Cast in one piece. Many lengths and widths. ` Tappings, top, bottom and ends. Complete choice of enclosures. Finished to harmonize with modem interiors. CAPITOLAIRE DIRECT FIRED CAPITOL THINTUBE RADIATORS 3-Tube Heights Per Section Heating Surface 25' 1.6 Sq Ft 4-Tube 2129'' 1.6 Sq Ft 1.8 Sq Ft 25" 2.0 Sq Ft 5-Tube 22' 2.1 Sq Ft 25' 2.4 Sq Ft CONDITIONING UNIT 6-Tube 19" 2.3 Sq Ft 25' 3.0 Sq Ft 32' 3.7 Sq Ft 1$4 in. Centers. 40 per cent less space needed for these graceful, efficient Capitol ThinTube Radiators. An air conditioning unit especially de signed for oil and gas firing. Streamline flue construction in preheating and prime heating sections insures high efficiencies. Deluxe jacket completely encloses all con trols, heating unit, automatic humidifier, filter and fan. Other gravity and forced air furnaces available for gas, stoker or hand coal firing. 983 Heating Systems Bone,,, ca,t-/r0n Weil-McLain Company Manufacturing Division: Michigan City, Ind. and Erie, Pa. General Offices: 641 W. Lake Street, Chicago NEW YORK OFFICES: 501 Fifth Avenue Prompt Weil-McLain Boiler and Radiator service is made conveniently available through local stocks carried by WeH-McLaln - Distributors in most of the Important distributing centers. New All-Fuel Boilers No. 67 and No. 77 Conversion type boilers with insulated enameled jacket. For hand or auto matic firing. Connected Load Ratings: Steam 325 to 1,030 sq ft, Water 520 to 1,650 sq ft. No. 73 Boiler for Automatic Firing Boiler has insulated en ameled de luxe jacket. Front or rear jacket ex tension available. Con nected Load Ratings: Steam 400 to 1,030 sq ft, Water 640 to 1,650 sq ft. "RO Series" Boiler for Automatic Firing Jacketed and insulated round boiler for small homes. Connected Load * Ratings: Steam 420 and' 520 sq ft, Water 630 and 790 sq ft. Square-Type Boilers Sectional boilers for larger installations. Com plete range of sizes. Con nected Load Ratings: Steam 650 to 9,300 sq ft, Water 1.050 to 14,900 sq ft. Self-Feed Boiler Magazine type boiler for small inexpensive sizes hard coal or coke. Con nected Load Ratings: Steam 240 to 7S5 sq ft, Water 3S5 to 1.260 sq ft. ----Junior Radiator's Occupy 40 per cent less space than conventional radiators of same rating. 3-tube, 3% in. wide; -4- tube,4jKs in. wide; 5-tube, 5% in. wide; 6-tube, 61J^6 in. wide. ' Concealed Raydiant Raydiant are convector type all cast-iron radiators made in Concealed, Partially exposed and Cabinet Types which differ from conventional convectors in that they supply in addition to convected heat, sun-like radiant warmth from a heat radiating panel. Their ability to hold heat longer helps increase the comfort of (on and off) automatic heating. Also, mixed installation of Raydiant and standard radiation is practicable. Solray is'a free standing cabinet type radiator with additional heating surface at back. 984 Heating Systems stoker. The Brownell Company Established 1855 Dayton, Ohio Manufacturers of BROWNELL BOILERS AND STOKERS Representatives In All Principal Cities Power Boilers of various Fire Tube Types; Steel Heating Boilers; Underfeed Stokers and Steel Plate Work. : Welded Boilers built in Standard and Master types. "Standard" type, Direct Draft, or Smokeless, Coal Hand Fired-- 500 to 34,000 sq ft. Stoker Fired-- 930 to 43.L30 sq ft. "Master" type, Coal Hand Fired--500 to 35,520 sq ft. Stoker Fired-- 1070 to 45,110 sq ft. Riveted Double Pass Firebox Boilers built for both high and low pressure. Coal Hand Fired-- 4000 to 35,000 sq ft. Stoker Fired--4SOO to 42,500 S(| ft. The Brownell Type "C" Stoker is built in both stationary dead plate and side dump types, in sizes suitable for medium and large industrial and heating plants. Brownell Type VC" Side Dump Stoker The Brownell Type " R" Heavy Duty Ram Feed Stoker is designed for use in the larger industrial and heating plants. Ruggedness, flexibility, economy and low maintenance costs are features of this stoker. Brownell Matched Units, Boiler and Stoker combinations, are available in sizes from 500 sq . ft to 45,000 sq ft. Brownell Type "R" Heavy Duty Stoker ' In addition to the above, a complete line of Domestic Stokers is built. These Stokers are built in either ratchet or continuous feed. Send for Descriptive Bulletins 985 Heating Systems stoker* Detroit Stoker Company Sales and Engineering Offices General Motors Bldg., Detroit, Mich. District Offices in Principal Cities Main Offices and Works at Monroe, Mich. Since 1898 Built in Canada at London. Ont. Detroit Stokers are unsurpassed for economy and dependability. The complete line includes both Underfeed and Overfeed Stokers of many sizes and capacities for all types of boilers, 30 Horse Power and up wards. All grades of Bituminous Coal are burned successfully. Operating costs are low. Detroit Stokers are of substantial heavy duty design, representing over 4(3 years' experience in Stoker manufacture exclusively. Materials of the highest quali ty are used. All Detroit Stokers erected and tested at the works and installed under the direction of experienced erection super intendents. Catalogs of various types will be furnished on request. Write Detroit Stoker Company, Detroit, Michigan, or district offices in principal cities. Detroit UniStoker with Detroit Ad justable Feed provides a wide range o coal feed control. Detroit Double Retort Stoker, a mul tiple retort side cleaning stoker for . medium size boilers. Detroit RotoStoker. {Stationary Grate Type). Ash removed through doors at grate level successfully burns a wide range offuels. Detroit UniStoker with Detroit Adj u stable Feed (Coal Feed Control) insures accurate fuel and air supply for best economy. Single Retort, Side Cleaning, for boilers approximately 125 to 250 horsepower. Detroit Double Retort Stoker, a Multiple Retort Stoker having two retorts with the side cleaning feature. For medium sized boilers having wide furnaces. Used to advantage where limited space con ditions prevent the use of the rear cleaning Multiple Retort Stoker. Detroit RotoStokers are Over feed Spreader Type Stokers, having an Overthrow Rotor ac tion, which insures uniform fuel distri bution over the en tire area. Offers ad vantages over other firing methods for burning inferior fuels and efficiently handling extremely fluctuating loads. 986 Each Detroit UniStoker with its motor or steam-turbine driven fullhoused blower is an independent unit, self-contained. Detroit Multiple Retort Stoker for large boilers and high capacities. An inclined fuel bed Stoker, possessing all outstanding modern features. Detroit RotoStoker (Dumping GraU Type) (Either Power or Hand Oper ated) for large boilers. Particularly suited to fluctuating loads. Detroit Stoker Company Heating Systems stoker* DETROIT LOSTOKER Detroit LoStoker is a complete me chanical firing unit in many grate area s;Zr^ and capacities for application to ai types of boilers from approximately 30 to 150 hp. Burns various grades of Bituminous Coal with high efficiency. Fuel is fed only when needed--none wasted. Single Retort, Side Cleaning, Adjustable Plunger Feed Type, mechanically driven from electric motor, requires little power for oper ation. Automatically con trolled from steam pressure water temperature room ther mostat, compact, easily in stalled, responsive and auto matic. A great coal saver. DETROIT LOSTOKER ADVANTAGES: _ ,, ... .. Continuous Adjustable Plung er Feed with control of the quantity of coal fed and its distribution. Heavy Mechanical Drive of simple design, requires little power. Detroit LoStoker readily applied to Firebox Boilers--built to fit the Furnace or Firebox. Coal Hopper with Agitator designed to clear Boiler Doors. Plunger Feed-side cleaning feature elimi nates arduous hand cleaning offires and corresponding losses. Side Cleaning with dumping grates, ashes removed through doors provided in the Stoker front. No hand cleaning. Agitator in coal hopper for con tinuous coal feed, cannot stick or jam with wet coal. Automatically Controlled. Motor or steam turbine driven, con trolled from steam pressure, water temperature or thermostat. Detroit LoStoker side elevation showingadjustable plunger feed. Many grate area sizes and capacities to fit the furnace and pro vide the proper grate area to readily handle heavy loads and also to operate efficiently under light load conditions. Detroit LoStoker (brickset type) for application to tubular or water tube boilers. Front Elevation of Detroit LoStoker {brickset type) arrows indicate fimv of air to all parts of fuel bed. 987 Heating Systems stokers Combustion Engineering Company, Inc. All Types of Fire and WaterTube Boilers Mechanical Stokers Complete Steam Generating Units Pulverized Fuel Systems 200 Madison Avenue, New York, N. Y. Offices in ail principal cities of the United States and Canada More than 14,000 C-E Stokers installed to date wear are readily accessible for inspection, adjustment or replacement, when neces sary. Rate of fuel feed and air supply may be regulated over a wide range and are readily adaptable to automatic control. Applicable to boiler units from about 100 hp up. C-E SKELLY STOKER UNIT A compact, self-contained unit adapted to burn either anthacite or bituminous coal. Alternate arrangement of fixed and* moving grate bars assures lateral distri bution of fuel. An integral forced-draft fan. with vortex inlet control, permits positive regulation of air-coal ratio. Auto matic control is standard equipment. Ap proximate application range--20 to 200. rated boiler hp. TYPE E STOKER A single-retort, underfeed stoker with an established reputation of many years' standing for dependable service. Designed to burn a variety of bituminous coals under boilers up to about 600 rated hp. Available with steam, electric or hydraulic drive. C-E SPREADER STOKER A simple, rugged stoker designed to burn a wide variety of coals. Hopper, feeding and distributing mechanism, variablespeed drive and motor are combined in a compact unit. A series of rotating spreader blades feeds coal into the furnace in criss crossing streams which assure uniform distribution. Fines are burned in sus pension and the rest of the coal is burned on a grate which may be of either the stationary or dumping type. Grate surface is zoned for regulating air admission and to facilitate cleaning. All parts subject to OTHER C-E STOKERS Type K Stoker--A single-retort, under feed stoker for burning bituminous coals under boilers in the upper size range of the C-E Skelly Stoker Unit. C-E Multiple Retort Stoker--For burning bituminous and semi-bituminous coals under boilers up to the largest sizes. C-E Traveling Grate Stokers -- Including both Coxe and Green types. Available with grate surfaces suitable for anthracite, coke breeze, lignite or bitumi nous coal, as required. Chain grate types are built for either forced- or natural-draft application. C-E BOILERS All fire tube and water tube types in sizes ranging from 25 hp up to the largest. Standard and special designs to suit all conditions of fuel, load and space. In cluded are all types formerly known by the trade names "Heine," "Walsh & Weidner," "Casey-Hedges," "Ladd" and "Nuway". 988 Heating Systems stokers Motorstokor Division Hershey Machine & Foundry Co. Factory and Home Office Manheim, Pa. MOTOR STOKOR Installation and Service by factory-trained dealers in all anthracite burning areas. DEFINITION ADVANTAGES A complete stoker, burner, and optional ash-removal system for automatic com bustion of buckwheat or rice anthracite. Applicable to coal, gas or oil furnaces or boilers for providing warm air, hot water, or steam. Especially designed for auto matically heating buildings and providing year-round hot water. Simplicity: Entire mechanism func tions intermittently, including coal feed, controlled draft, and ash removal. A portion of the combustion air is fed with the coal, preventing dust and back draft. Worm feed. Concentric dustless ring burner needs no cleaning. Revolving bar breaks all clinkers. RANGE OF TYPES Efficiency: Fixed air mixture for uni Standard installations in all sizes include direct-from-bin feed with ash removal, direct-from-bin feed with pit collection, hopper feed with ash removal, and hopper feed with pit collection of ashes. form combustion. Floating worm assures uniform, trouble-free coal feed. Flexibly mounted motor operating intermittently and using little current. Quiet, directmounted, self-compensating fan. Ruggedness: Heavy cast parts, with RANGE OF SIZES lavish use of chrome-moly, monel, nickel, Available in 12 models, providing a com plete range. The smallest is the new domestic MOTORSTOKOR No. 10 cap able of heating average small homes. It feeds up to 20 lb of anthracite per hour, is and special alloys. Oil-submerged gears reduce all operations to very slow wear- free motions. Extraordinary structural and metallurgical protections against cor rosion. '- rated at 640 sq ft of steam and 1020 sq ft of water radiation. The largest are MOTORSTOKORS No. 2 and No. 3, feeding up to 100 lb of coal per hour and rated at 2800 sq ft of steam or 4480 sq ft of water radiation. Safety: Floating coal screw minimizes stoppage or jams. Air feed through coal prevents back draft and escaping gas'. Automatic release-clutch cuts off current when over-loaded. Mirineapolis-Honeywell controls. The new MOTORSTOKOR No. 10 marks its menu- acturer s new low in the'first cost of completely automatic anthracite equipment. MOTORSTOKOR AF for heavy-duty service in apartments, office buildings, etc. Bin-feed pipe at left. Ash removal system at right. 989 Heating Systems stokers Iron Fireman Manufacturing Company Automatic Coal Burners Portland, Oregon Factories: Portland, Orb.; Cleveland, Ohio; Toronto, Canada . Retail Branches or Subsidiaries Chicago, III.; Milwaukee, Wis.; St. Louis, Mo.; New York, N. Y.; Brooklyn, N. Y.; Montreal, Can. ' Dealers in Principal Cities and Towns in the United States and Canada Representation in numerous foreign countries . IRON FIREMAN Automatic Coal Burners Both Underfeed and Overfeed Stokers--Iron Fireman underfeed stokers are made in capacities from 20 to 1500 lb of coal per hour. These stokers feed fuel to the fire from below, under forced draft. As the coal approaches the fire, it is gradually heated. Volatile gases are distilled off in the presence of an excess of oxygen and are thoroughly ignited while passing through the firebed. With bituminous models, ash is fused into clinkers which are easily removed. Anthracite models pro vide for automatic or spill-over ash re moval. Iron Fireman overfeed stokers are of the Pneumatic Spreader type, with capacities ranging from 600 to 3200 lb of coal per hour. The Pneumatic Spreaders transport coal from hopper or bunker on a stream of high-velocity air (where desired, hot gases from the furnace may be used in conveying systems). Discharged from nozzles within the boiler front, the fine particles of coal are burned in suspension, and larger pieces burn in a shallow layer on flat grates. Advantages--Iron Fireman saves money and in creases heating plant efficiency in four major ways; (1) Cuts fuel costs; (2) Reduces labor costs; (3) Provides steady, Typical Installation Down even heat or Draft Firebox Boiler ' power; (4) Elimi nates the smoke nuisance. Installation and Sizes--Iron Fireman is made in a range of hopper and bin-feed sizes for commercial heating and power boilers and also for homes. It can be installed quickly in practically any solid fuel boiler or furnace, old or new. Machines are shipped complete from the factory. All parts are stand- dard and interchangeable. Features of Design and Construc tion--Construction and operation of the Iron Fireman are characterized by sim plicity throughout. Outstanding features of design and construction are: (1) Pressed steel construction. (2) Precision transmission; drop forged gears; gears run in bath of oil. (3) Electric motor-- standard make. (4) V-belt drive. (5) Safety shear pin protects mechanism from damage. (6) Quiet ball bearing mounted fan sup plying forced draft to fire. (7) Auto matic fire banking damper--con serves fuel and holds fire in proper condition when stoker is idle. (8) Positive pneu matic fume elimi- Typical Installation Four Drum Water Tube Boiler # nator--an auxiliary air supply that insures positive movement of all gases through the fire. (9) Volumeter that supplies exactly the amount of air needed for perfect com bustion regardless of fuel bed conditions or type of coal used. (10) Conveyor screw made by exclusive process; cold rolled steel wrapped in spiral, welded to steel core; is strong and long wearing. (11) ' Iron Fireman Manufacturing Co. Heating Systems stokers Commercial Model--For Heat or Power Automatic electric controls designed for and used exclusively on Iron Fireman. Automatic Controls--Iron Fireman directing controls include many exclusive and outstanding features. All relays and controllers employ master control switches operated remotely by small, powerful motors. Refueling timers, which main tain a small pilot fire in mild weather, are interlocked with these motors for complete recycling after every operation, an exclusive improvement that eliminates overheating. The Syncrostat, a de luxe controller, combines master switch, refueling timer, day-night time switch, fused line switch and an outfiretimer. Simpie adjustment Typical InstaUalion Cast Iron Boiler and connection of this device, which em ploys a safety type circuit, permits choice of four combinations of refueling and outfire programs to suit various requirements. Thermostats and warm air, hot water and pressure regulators are of advanced design and construction. They combine accurate dependable operation with long life and attractive appearance. Iron Fireman for Homes--The Iron Fireman residential model employs "Forced Underfiring" principle the same as larger machines, with simplified operation. Can be used for any steam, hot water or vacuum system or warm air furnace. Quickly installed. Hopper and bin-feed models for both bituminous and anthracite coal. Anthracite models have been tested and approved by The Anthracite Institute. Typical Installation Domestic Furnace Unit Heatmaker, Self firing Room Furnace ENGINEERING SERVICE The Iron Fireman organization is nationwide. Trained men--backed by one of the largest manufacturing organiza tions in the field--are at your service to help you with the experience and practical heating information gained through servic ing thousands of boiler rooms and heating plants in all parts of the country. CATALOG AND INFORMATION Catalogs give full information about the Iron Fireman. Descriptive folders give special data about installation in particular types of industries and in homes. Iron Fireman in Operation in Horizontal Return Tubular Boiler, Low Bridge Wall 990 Commercial Installation--Coal Flow model that carries coal direct from bunker to fire Pneumatic Spreader Model--For High Pressure Boilers Industrial "Poweram" Model--For Heal or Power 991 Heating Systems Burners, Gas The Barber Gas Burner Company 3704 Superior Ave., Cleveland, Ohio Address Michigan inquiries to The Barber Gas Burner Co., of Mich., 4475 Cass Ave.. Detroit. Mich. Barber Automatic Jet Gas Conversion Burners, for heating and air conditioning equipment, have a record of high efficiency, for a period of over 20 years, giving con tinuous satisfaction in many thousands of homes and other buildings in United States and Canada. The exclusive Barber Jet principle of combustion, attaining 1900 deg flame temperature on atmospheric pressure, and other basic advantages of design, have, given Barber a permanent place in modern heating and air conditioning practice. Barber Burners for gas burning appliances have been adopted as standards by many appliance manufacturers. Shown here are only a few items from Barber's complete line. Illustrated No. 38A Catalog and Price List furnished on request. - 5%-------- =--------- - ---------------------------- 10"' . ` Heating Systems Burners, Gas The Webster Engineering Co. 419 West 2nd St., Tulsa, Oklahoma Division of SURFACE COMBUSTION CORP-, TOLEDO, OHIO WECO-N.G.E. SERIES F600 GAS BURNERS 50,000 to 10,000,000 Btu Output No. C. L-90 Burner Unit Conversion Burners ; for Furnaces or Boilers Burners are adjustable as to diame ter, on the job, to fit practically all round grate sizes. Also to fit grates of oblong furnaces and boilers. Listed in the A.G.A. Directory of Approved Ap pliances. Equipped with automatic controls with motor gas valve, with magnetic gas valve control, with quick acting gas valve control (for buildings equipped with automatic heat control), or in "M" series with manual control. Barber Burners and Regulators are Adaptable to: Air Conditioning Equipment, High Pressure "Boilers (Tubular and Tubeless), Bakery Ovens, Garage Heaters, Coffee Urns, Hair Dryers, Space Heaters, Floor Furnaces, Clothes Dryers, Water Heaters, Confectioners' Stoves, Vulcanizing Machines, Pressing Machine Boilers, Japanning Ovens, Core Ovens, Banana Room Heaters, Other Appliances. Gas Burner Specialists offering Engineering Department and Laboratory facilities for Gas Burner problems. Consultation invited. 992 For Use in Any Steel Firebox or Sectional Boiler The Series F600 venturi tube is 6M' wide, 10$' long, as shown (at right) and the complete assembly is only 15' high. An infinite number of assemblies are possible by proper arrange ment of the individual tubes. For complete sizing information see Bulletin F600H. Improved venturi and greater port area insure much higher capacities at lower pressures. Unique baffles at the outlet of the mixing tube make possible perfectly even distri bution of flame completely around the baffle brick. As a result the maximum flame length is greatly reduced. Interchangeable grills with multiple ports can be varied to suit the combustion char acteristics of various gases. The proper sizing of these grills prevents any possi bility of flash back. In addition to the above major improve ments the F600 possesses the same desir able features that made the 600 so popular. 1. Simple installation requiring no ex pensive insulated combustion chamber and having no furnace radiation loss. 2. Extreme quietness due to low rate of combustion over a large area. 3. Flexibility from infinite number of possible combinations varying both size and shape to meet load and firebox con ditions at various gas pressures. 4. High radiant transmission rate due to radiant temperature of the standard fire brick baffles on the top of the burner tubes. 5. Low draft loss because of ample secondary air openings. 6. Plain gas pilots of heat resistant material and of a design that will hot allow flame to pull off. 7. Safety pilot applied in a cool , zone in a manner that insures perfect direct ignition of the burner yet allowing the the thermal element to cool quickly upon flame failure. 8. Guaranteed vibrationless under all conditions. CAPACITY OF SINGLE F600 VENTURI TUBE--No. 16 M. T. D. ORIFICE Manifold Gas Pressure 0.5' W.C. Input--Cu Ft, 1 hr... 26.5 Output--Sq Ft, St. Rad 81 Output--Boiler HP... 0.58 1.0* W.C. 40.5 124 0.89 2.0' W.C. 60.5 165 1.33 3.0' W.C. 75.0 229 1.65 4.0' W.C. 87.0 267 1.91 5.0* W.C. 6.0' W.C. 98.0 108.0 301 331 2.15 2.37 4 02 116.0 355 2.54 6 02 143.5 440 3.14 8 02 166.5 510 3.66 993 Heating Systems Burners, on TODD COMBUSTION EQUIPMENT, nc. (Division of Todd Shipyards Corporation) 601 West 26th Street, New York City New York Mobile New Orleans Galveston Seattle Buenos Aires London THE TODD VARIABLE CAPACITY MECHANICAL PRESSURE ATOMIZ ING BURNER provides unlimited firing range without change of burner tips, oil delivery pressure or angle of spray. It can operate under automatic control with out loss of efficiency over all firing ranges. Fuel Supply is forced into the Variable Capacity Burner at a constant pressure of 300 lb per square inch, regardless of fuel consumption desired. Maximum capacity fuel load enters continuously and the intake line is without reducing valves. Atomizing pressure, spray orifices and angle of spray are constant and atomi zation efficiency assures constantly satis factory performance. This Variable Capacity Burner burns the required quantity of oil per burner, per hour, to meet load conditions . . . with one point valve control and instant vari ability. It is designed for use in conjunction with any of the standard Todd air registers for firing practically any type boiler of 100 hp capacity or larger operating at 50 lb working steam pressure or higher and can be installed in almost any existing station ary or marine steam plant. Send for de scriptive literature. RECENT INSTALLATIONS OF TODD VARIABLE CAPACITY BURNERS: New York Hunter College Hotel McAlpin Presbyterian Building Millinery Towers State Hospital for Malig nant Diseases S. M. Frank Pipe Co. 98th St. Municipal Pump ing Station New Jersey Sonoco Paper Products Co. E. R. Squibb & Sons Co. Art Color Printing Co. Connecticut Pratt & Whitney Machine Tool Co. International Silver Co. Lee Hat Company Mallory Hat Company Bryant & Chapman Milk Co. Jenkins Valve Co. Amer. Hatters & Furriers Sikorsky Aircraft Corp. Clifton-Wright Hat Co. Massachusetts Uxbridge Worsted Co. - Illinois A. Finkl & Sons Co. Greys Lake Gelatin Co. Hales & Hunter Co. "Washington, D. C. Woodward & Lathrop Stores New Hampshire U. S. Navy Yard, Ports mouth Washington U.S. Navy Yard, Bremerton Canada International Foils Co., Ltd. Montreal City Hall Annex TODD ALSO MANUFACTURES: Mechanical Pressure Atomizing Oil Burners; Horizontal Rotary Oil Burners; Oil Burning Air Registers for Natural Draft, Assisted Draft, Induced Draft or Forced Draft; Inside Mixing Steam Atomizing Oil Burners; Combination Gas and Oil Burners; Furnace Doors and Interior Castings for converting Howden Type Furnace Fronts to oil firing; Oil Burning Galley Ranges; Oil Heating, Pumping and Straining Equipment. Todd engineers are always available for consultation and analysis of combustion problems--without obligation. 994 Heating Systems Pip and Fittings Arthur Harris & Co. 210-218 N. Aberdeen (formerly Curtis) Street Chicago, HI. ENGINEERS -- FABRICATORS OF NONFERROUS METALS AND STAINLESS STEEL Metals Fabricated--Aluminum, Block Tin, Brass, Bronze, Copper. Everdur, Monel, Nickel, Inconel, Stainless Steel and KA2 SMO. Bulletin on request. Coils For heating, cooling and condens ing. All shapes made from any size pipe or tube--standard or special connections, of copper, brass, alumi num, stainless steel, KA2 SMO, monel, inconel, nickel, block tin, and Everdur. Metal Floats Ball Cylindrical Flat Cylindrical Cylindrical Column Made of copper, plain steel, stainless steel, KA2 SMO, aluminum, brass, Monel, pure nickel, ADMIRALTY and Everdur, for open tank and all pressures. Seamless copper ball floats carried in stock in diameters of 3 in., 4 in., 5 in., 6 in., 7 in , 8 in., 10 in., 12 in. for open tank and pressures of 25; 50, 100 and 150 lb. Floats in special sizes and pressures--made to order. Stainless steel ball floats 2 Hi in. to 12 in. for high pressure and corrosion carried in stock--special stainless steel floats made to order --stainless steel ball floats larger than 12 in. diameter can be made up specially. Float catalog sent on request. . Copper Expansion Joints For low pressure and vacuum. Made in two styles--convex and concave. Sizes 4 in. to 60 in. diame ter. Cast iron or steel flanges. Flanges drilled to American stand ard unless otherwise ordered: B-290 available only in sizes 4 in. to 15 in. inclusive. B-280 Convex B-281 Concave B-290 Convex Bends We make bends in every shape from all sizes of copper water tube, pipe and tubing in copper, brass, aluminum, stainless steel, monel, tin and nickel. Standard or special connections. U-bends for storage water heaters. Also special pipe work for industrial installations, plumbing, heating and brewing. Perforated pipe, double pipe coolers, etc. Non-Ferrous Castings--"Dairywhite" nickel silver for Process Industries Equip ment. Suitable for milk and food products machinery. Castings also of 88-10-2, 80-10-10, 85-5-5-5 and special mixtures. Many patterns available without charge. 995 T' Healing Systems PumPS Buffalo Pumps, Inc. 450 Broadway, Buffalo, N. Y. Branch Offices Albant, N. Y.. 1305 Standard Bldg., H. S. Johnson Atlanta, Ga., 1454 Piedmont Ave., N.E., J. J. O'Shea Baltimore, Mo., 508 SL Paul St., E. E. Thompson Boston, Mass., 4S6 Main St., Melrose Station. E D. Johnson Chicago, III., 20 N. Wacker Drive, L. D. Emmert Cincinnati, Ohio, Building Industries Bldg., F. W. Twombly Cleveland, Ohio, 418 Rockefeller Bldg., T. A. Weager Dallas, Texas, 702 Tower Petroleum Bldg., T. H. Anspacher Davenport, Iowa, 305 Security Bldg., D. C. Murphy Co., Inc. Denver, Colo.. 1718 California St.. Stearns Roger Mfg. Co. Des Moines, Iowa, 214 Old Colony Bldg.. . D. C. Murphy Co., Inc. Detroit, Mich., 2051 W. Lafayette Blvd., Coon-De Visaer Co., T. E. Coon Greenville. S. C., 312 Franklin National Life Bldg., R. A. Stipp Kansas Citt, Mo.. 428 Dwight Bldg., A. E. Williams Los Angeles.Calip.. 708 Pershing Sq. Bldg., P. R. Adrianse Minneapolis, Minn., 2102 Fcehay Tower, E. F. Bell New Orleans, La., Devlin Bros.. 1003 Maritime Bldg. New Yore, N. Y., 39 Cortland St.. W. S. Koithan . Philadelphia. Pa.. 703 Cunard Bldg.,- Davidson A Hunger Pittsburgh, Pa.,' Power Equipment Co.. Oliver Bldg. Richmond, Va., T. Spencer Williamson. Jr., Inc., '' Mutual Bldg. San Francisco, Caliv., 1625 Van Ness Ave., Moore Machinery Co., J G. Scott Seattle, Wash., 500 First Ave., So., A. T. Forsyth St. Louis. Mo.. 1598 Arcade Bldg., J. W. Cooper Toledo, Ohio, 1922 Linwood Ave., C. M. Eyster Washington, D. C.. 640 Woodward Bldg., G. S. Frankel Complete line manufactured in Canada bt Canada Pumps, Ltd., KrrCHENER, Ont. PRODUCTS--A complete line of Single and Multi-stage Centrifugal Pumps, Steam Pumps and Special Pumps for use in all types of heating and air conditioning installations. Buffalo Double Suction Single Stage Centrifugal Pumps Buffalo Single Suction Closed-Coupled Pumps Heating Systems Pumps i Chicago Pump Company ^'5330 Wolfram Street BRUnswick 4110 Chicago PRODUCTS--Return Line Vacuum Heating and Boiler Feed Pumps, Con densation, House, Booster, Fire Pumps, Circulating, Brine, Sewage, Bilge, Sludge, Pneumatic and Tankless Water Supply Systems and Automatic Alternator for Duplex Sets of Pumps. "CONDO-VAC" Return Line Vacuum Heating and Boiler Feed Pump "Sure-Return" Condensation Pump for Low and Medium Pressure, and Systems up to 35,000 Sq Ft Radiation For general service where clear water is handled you will get top performance with these pumps. They embody all of the accepted modern features of centrifugal pump design. Capacities range from 10 to 60 thousand U.S. gallons per minute. Buffalo Self-Priming Single and Double Suction Centrifugal Pumps This pump is close-coupled to electric motor, eliminating the necessity for bear ings. The impeller is overhung on the motor shaft, providing a compact, easilyserviced unit. Permanent alignment is assured and the pump mounted in this manner requires" very little space. Buffalo Close-Coupled Pumps are suitable for handling hot water with low submergence on suction, or for operating with suction lift as high as 25 ft. These pumps are also available in special alloys. Now available with positive self-priming device built with the pump. This primer is built under license from the Nash Engi neering Company and is fully covered by patent. Buffalo Self-Priming Pumps offer these advantages: (1) All working parts are above the liquid to be pumped. (2) There is complete access to all parts of instal lation. (3) Rotors are balanced--vibra tionless. (4) Buffalo Self-Priming Pumps are very quiet--no long shafts to vibrate and fewer bearings. (5) Constant positive prime obtained without foot valves. Buffalo Automatic Sump Pumps Buffalo Sump Pumps are selfcontained and have unusually high efficiencies thus permitting the use of small motors. Ball bearing thrust and enclosed shaft especially adapt these pumps for their service. 996 Fig. BIOS--Duplex "Condo-Vacs" with Duplex Double Automatic Control No vacuum on stuffing boxes, ample clear ance in rotating member. It costs less to operate a "Condo-Vac." "Condo-Vac" reduces corrosion in piping and boiler to minimum--because pump does not take in air from atmosphere and entirely elimi nates all air coming back from system. "Condo-Vac" is quiet, has a low inlet, entirely automatic, fool-proof, easy to maintain. Ask for bulletin 270. Fig. 1946 "Sure Return" Condensation Pumps and Receivers are built for systems up to 35,000 sq ft of direct radiation and for low and medium pressures. Built in either single or duplex units. Duplex units are alternated in their operation by the Auto matic Alternator. Complete data in Bulle tin 250. Vertical Condensation Pumps for Low and Medium Pressure for Systems from 500 to 100,000 Sq Ft Radiation Close-Coupled Pumps Boiler Feed. Circulating, Tank Filling, Water Supply Fig. ISO--Close-Coupled, side suction pump. Capac ities range from 3 to 600 Gpm against heads up to 189 ft. Motors from 1/6 to 0 Hp. Discharge 1 to 3 in. Both closed and open type impellers. - Fig. 1940 Condensation Pnmp The vertical condensation pump is designed to re ceive returns from lowest radiation. The receiver is placed underground--an ordinary hole sufficing if necessary -- and requires very little floor space. Unit is shipped complete, easy to install, assembled so as to prevent steam leaks. Special bearings will stand up under hot water for several years. A special float mechanism is guaranteed not to leak or stick in stuffing box. Complete data and descriplion in Bulletins 245 and 255. 997 Heating Systems Pumps The Nash Engineering Company 217 Wilson Road South Norwalk, Conn., U. S. A. Sales and Service Offices In all Principal Cities Return Line Vacuum Heating Pump Standard with the heating industry for over seventeen years. Removes air and conden sation from return lines of vacuum steam heat ing systems, discharging air to atmosphere and returning water to the boiler. Two independent units are combined in a single casing--an air unit and a water unit. Impellers of both are mounted on the same shaft. Pump is bronze fitted throughout. Supplied direct connected to standard elec tric motors, for belt drive, or for steam turbine drive. For continuous or automatic operation. Standard in capacities up to 300,000 sq ft E.D.R. Larger units special. Bulletins Nos. 307, 308, 309, and 310 on request. Vapor Turbine Vacuum Heating Pump Jennings Vapor Turbine Heating Pumps combine all advantages of the standard return line heating pump with a new type of drive, a specially designed low pressure turbine which operates directly on steam from the heating mains on any system, requiring a differential of only 5 in. of mercury, and returns that steam to the heating system with practically no heat loss. This pump affords the safety and economy which goes with continuous condensation re turn and steady vacuum, and at no cost for electric current. Furnished standard in capa cities up to 65,000 sq ft E.D.R. Larger units special. Bulletin No. 290 on request. Condensation Pump and Receiver Removes the condensation from radiators in return line steam heating systems, particularly radiators set below the boiler water line level, and pumps the condensation back to the boiler. Pump is bronze fitted with enclosed centrifugal impeller of improved design. By making the pump casing a part of the return tank, and bolting the motor base to the tank, floor space is conserved. The rectangular construction permits installation in a corner against the wall. These pumps are furnished in standard sizes with capacities ranging from 1^ to 225 gpm of water. For serving up to 150,000 sq ft of equivalent direct radiation. Bulletin No. 241 on request. 998 Heating Systems Pumps The Nash Engineering Company 217 Wilson Road South Norwalk, Conn., U. S. A. . Sales and Service Offices in all Principal Cities " : Centrifugal Pump Made in standard and suction (self-priming) types. For circulating hot and cold water; boosting city water pressure; handling water in air washing and conditioning; handling ash sluicing water, etc. Compact--motor armature and pump im peller are mounted on the same shaft. Simpli fied--no bearings in pump casing, one stuffing box. Accessible--impeller removable without disturbing piping or shaft alignment. Self-priming types will handle air or gas con tinuously with liquid being pumped, and can be operated intermittently without foot valve. Supplied in 1, 12, 3, 4, 6, and 8 in. sizes, with capacity up to 2000 gpm. Heads up to 300 ft. Bulletin No. 155 on request. Suction Sump and Sewage Pumps Jennings Sump Pumps are self-priming cen trifugals for handling seepage water and liquids reasonably free from solids. Sewage Pumps are equipped with non-clog type im peller for liquids containing solids. Suction piping only is submerged. Centrifugal impeller and vacuum priming rotor are mounted on same shaft that carries rotor of the driving motor, forming a single moving element, ro tating without metallic contact. . Will handle air or gas with liquid being pumped, and because of self-priming feature are installed entirely outside of pit, affording perfect accessibility for inspection or cleaning. Capacities to meet all requirements. Bulletins Nos. 159, 161, and 275 on request. Air Compressor and Vacuum Pump Nash Air Compressors operate on a unique and different principle. The one moving part rotates in casing without metallic contact. There is nothing to wear, and no internal lubrication. " Nash Compressors deliver absolutely clean air; ideal for agitation of liquids, pressure displacement, and handling gases. Vacuum pumps ideal for priming pumps, b/oocf sucking pumps in hospitals, and wherever non-pul sating vacuum is required. Pressure 75 lb or vacuum 27 in. of mercury. Furnished for any capacity; special for higher vacuums and pressures. Bulletins Nos. 252, 255, 282, and 298 on request. 999 Healing Systems Expansion joints ^DSCO PRODUCTS for STEAM SERVICE American District Steam Company North Tonawanda.N.Y. IN BUSINESS OVER SIXTY YEARS Branches and Agents In Principal Cities PACKLESS, U-RING TYPE JOINT A compact, fully guided; packless joint with steel body and fully enclosed expan sion element for high pressures and high temperatures. Requires no servicing; The element is a series of welded U-rings of stainless alloy steel. Particularly adapt able where space is limited. Pressures to 300 lb and temperatures to 750 F. Write for Bulletin No. 35-50AG. PISTON-RING EXPANSION JOINT Piston rings in the guide ring attached to the inner end of the slip hold the line pressure, enabling the joint to be unpacked and repacked under full operating pressure without interruption to service. A fully guided joint for pressures to 400 lb and temperatures to 750 F. Slip cannot pull out of body. Write for Bulletin No. 35-15G. Piston-Ring Type Joint Rotary Condensation Meter ADSCO Instantaneous Water Heater ROTARY CONDENSATION METER Measures steam consumption by meter ing condensate from heating systems or industrial equipment. Accurate within 1 per cent and factory tested to 150 per cent of rated capacity. Compact, easily cleaned, tamper-proof and equipped with non-fogging counter mechanism. Counter reads directly in pounds. Suitable for vacuum or gravity service. Available in 7 sizes from 250-12,000 lb per hour capa city. Write for Bulletin No. 35-80AG. ADSCO HEAT EXCHANGERS Made in various sizes and capacities to heat or cool water, oils, other liquids or gases according to expert engineering specifications. Simple in design, sturdy in construction, dependable and economi cal in operation. Available in U-tube or straight tube types of heaters, economizers, condensate coolers or special units. Write for Bulletin No. 35-75BG, 35-76G. ADSCO Vertical Steam Trap ADSCO VERTICAL STEAM TRAP . A float type steam trap with or without thermostatic air by-pass for vacuum ser vice to 15 lb pressure and gravity service to 125 lb pressure. The cover with all working parts can be removed without disturbing the piping connections. The trap is equipped with a reversible valve and reversible seat of stainless alloy steel. Write for Bulletin No. 35-86G. (See also Page 1014) Heating Systems vaires. Air Anderson Products, Incorporated . Cambridge, Massachusetts />,' -J Yent-Rite Radiator Air Valves. Vent-Rite Control Valve No. 66. The VentRite Balancer. Originators of "Balanced Radiation by Controlled Venting.'' Cross Section ' No. S Vent-Rite The complete Line of Vent-Rite Air Valves comprises nine valves of various types, sizes, outlets and venting capacities. All are noiseless in operation, positive in action, close thermo statically under temperature. Vent-Rite Vacuum Valves do not depend upon a ball or disc to maintain vacuum in a system. Vacuum is maintained by means of a sensitive and positive acting bellows. This bellows is internally subjected at all times to atmospheric pressure which elongates the bellows, and closes the vent when the internal pressure in the valve is less than the atmospheric pressure. Venting takes place through an adequate, straight line venting orifice, which is accurately set by means of a modu lating adjustment of the valve pin, toward or away from the valve seat. The adjustment is underneath the valve--out of sight; cannot be disturbed by accident or meddlesome fingers. These Vent-Rite features insure Permanent, "Balanced Radiation" of any one-pipe steam system, which means--the quick, uniform transfer of steam to all radiators regardless of their number, sizes or distances from the boiler. All Vent-Rites are made of the finest non-rusting---noncorroding materials throughout to insure years of trouble-free service. Bases are Brass Forgings, Valve Pins are nickel silver. Valves are of attractive modern design, finished in chromium. Vent-Rites can be taken apart for examination or cleaning and can be tightly reassembled. Union couplings with special heavy copper-asbestos gaskets insure leak-proof joints. Only Vent-Rites can be taken apart for thorough cleaning No. 66 Control Valve THE VENT-VAC METHOD OF STEAM CONTROL The Vent-Vac method of steam control makes a modern efficient system from any automatically fired one-pipe steam installation, eliminates lagging radiators and overheated rooms, assures "Balanced Radiation." The new Vent-Rite Control Valve No. 66 is non-electric, is simply installed by screwing it in the place of a main line vent. The No. 66 restores the system to atmospheric pressure at the beginning of the firing cycle, and also limits the amount of vacuum created to 10 inches--beyond that point the relatively low Btu content of the vapor due to increased volume makes its transfer from boiler to radiator uneconomical. Used with Vent-Rite Valves, the system is complete, superior in performance, profitable. Write for details for any sized installation. 1001 Heating Systems Specialties Armstrong Machine Works 851 Maple Street Three Rivers, Mich. Representatives in Ail Principal Cities Armstrong offers two types of traps for heating, air conditioning, and steam distri bution service. Standard Inverted Bucket Traps, the type originated by Armstrong, are non airbinding and self-scrubbing. They are used for low,'medium, and high pressure service where relatively little air must be handled along with the condensate. Their free-floating lever design makes it possible to open very large discharge orifices com pared with the size of the trap itself. Armstrong Blast Traps are used where large amounts of air must be vented quick ly when steam is first turned on. They have several advantages over the conven- ' tional float and thermostatic trap. 1. The Armstrong Blast Trap has but a single orifice to be maintained tight against' the full pressure differential. 2. Positive action. The discharge valve in an Armstrong Blast Trap is either wide open or tight shut. Fast opening and fast closing prevent wire-drawing. 3. Handles dirt. There ate no dead spots in an Armstrong Trap in which dirt can settle and interfere with.the operation of the trap. . Armstrong Machine Worths Heating Systems Specialties Part No. />. I &2 3 4 5 6 7 8 9 10 It 12 13 MATERIALS USED IN ARMSTRONG TRAPS | Name | Material Cap and Body... Scat........................ Guide Plate Pins. Valve..;................. Lever...................... Bucket. Retainer................. Gasket.................... Bolts and Nuts... Thermic Vent.... Test Plug.............. Bucket Weight... Cast Semi-Steel, 33.000 lb tensile strength Chrome Steel Stainless Steel 18-8 Chrome Steel Stainless Steel 18-6 ` ' Brass or Stainless Steel Stainless Steel 18-8 Compressed Asbestos 14 " Steel 90,000 lb minimum tensile ' Stainless Bi-metal and Stainless Steel Steel Castflron - ' Valve and Seat are heat treated after machining. 4. The wearing parts in all Armstrong Traps are identical in design, material, and precision workmanship with parts used in Armstrong Forged Steel Traps for pres sures up to 1500 lb gage and total tempera tures of 850 F. Armstrong Steam Trap Book. This 36 page book gives complete information on all sizes and types of Armstrong Traps. It also contains 17 pages of data on the subject of trap selection, installation, and maintenance. A free copy will be mailed on request. ' - Cross-section of No. 200 ") and No.- 202 04') `raps for straight-through connections. ALL Armstrong traps are readily convertible into "Blast" type traps merely by using buckets equipped with the patented auxiliary thermic air vent. As shown in the above sketches, the mechanism for this vent consists of a stainless steel disc slotted to receive the end of a bi-metal strip. Different coefficients of expansion in the bi-metal cause it to bend down when cold and up when hot.. Normally, it is set to close at 212 deg, but it ca_n be set to close at higher temperatures. Capacity, 500 to 1500'cu ft of free air per hour depending on size of bucket. Traj)S No. 200-203 Trap Size . [No. 200 ' No. 201 No. 202 No. 203 Pipe Connections........... List Price (Regular). . . List Pnce (blast 1 rap) Telegraph Code (Blast Trap)... " B ................. " C................. " D............... " E............... Maximum Pressure, lb Continuous discharge 5 capacity in lb of water i 15 per hour at pressure 2 20 indicated, For more complete information see the Capacity Chart in Armstrong 50 ^ 70 Steam Trap Book. 125 Vi" $7.00 $8.50 Acacia Acaeette. / w 6 / 41b 125 Vi' $7.00 $8.50 Acanthus Acanette w w 2" / 6 v." 41b 125 450 450 560 560 640 640 690 690 500 500 580 580 660 660 640 640 680 680 V." $7110 $8.50 (Juacia Ouacette 3%" 4W . 5" 6 Vs* 4 lb 125 450 560 640 . 690 500 580 660 640 680 y." $7.00 $8.50 Quanthus Quanette 3}4n 5hi" w 6 Vs" 4 lb 125 450 560 640 690 500 580 660 640 680 1002 Trap Size Pipe Connections................................ .. List Price (Regular)............................. List Price (Blast Trap)....................... Telegraph Code (Regular).................. Telegraph Code (Blast Trap)............ Height................ DimensionB........... Diameter................ " A ......... Wall Thickness " C............. Diameter of Bolts................................. Number of Bolts.................................... Weight...................................................... Maximum Pressure............................... Continuous discharge capacity in lb of water per hour at pressure indicated. For more complete information. see the Capacity Chart in the Armstrong Meam 1 rap Book. 5 10 15 o 20 5 30 8 50 70 _Q 100 -1 125 150 200 250 Traps No. 211-216 No. 211 No. 212 No. 213 '/zn $ 9.25 $10.75 Aspen Aspette w 4'/" V." 6 %Ib 200 >/2"orV4? $15.00 $17.00 Birch Birette 8" 5n l/4n l/4n 8 IO/2lb 200 '/znory4" $20.75 . $22.75 Walnut Walette 104" y$n 56" Vs*1 6 191b 250 830 950 1060 880 1000 840 950 860 950 810 860 900 1600 1900 2100 1600 2050 1900 2200 1800 2000 1500 1600 1680 2900 3500 3900 3500 4000 4100 3800 3600 3900 3500 3200 3500 1003 No. 214 1" $29.00 $31.50 Hemlock Hemlette l2/;n W v 34" 8 32 lb 250 4800 5800 6500 6000 6800 6300 6000 6200 6700 5700 5300 5700 No. 215 1 n or l/4 $38.00 $40.50 Larch liLarette - 14" % Vzn 8 47 lb . 250 7600 9000 10000 8500 9800 9000 9200 10400 10900 9500 9200 7000 No. 216 V/zn or 2M $55.00 $60.00 . Tamarack Tamrette 163/4 iov Vzn 12 801b 250 14500 17300 19200 ' 18500 16000 18200 18300 16000 20000 18500 17500 19000 Healing Systems Expansion Joints E. B. Badger & Sons Co. General Office: 75 Pitts Street, Boston, Mass. Agents Atlanta, Ga.... ..... .............. ............. ,,140 Edgewood Ave. Buttalo, N. Y_-- .................. --361 Delaware Ave. Charlotte, N. C...... ................... 1408 Independence Bldg. Chicago, Ilu--__1307 S. Michigan Ave. Cincinnati, Obio._ __ 831 Temple Bar Bldg. Cleveland, Ohio_. ________ Guardian Bldg. Dsnvbr, Colo72S Denver National Bldg. Detroit, Mich................................... .................. ....... 424 Book Bldg. Hodbton, Tex.1________ ....P. 0. Box 2217 Indianapolis, Ind_____ __________ _825 Occidental Bldg. Kansas Cut, Ma_____ ___ __ _____ I.1332 Oak St. Los Angeles, Cali.,,.__ ________ __ 609 S. Anderson St Minneapolis, Minn______ ____________ 732 Builders Exchange Montreal, Qu*._.......-.......................... ............ 1411 Crescent St. New Orleans, La............. .............. 916 Union St., Room 203 Pittsburgh, Pa____ 302 Benedum Trees Bldg., Fourth Ave. Salt Lake Citt, Utah ......._Kearns Bldg. San Francisco, Cal it ......JSharon Bldg. Seattle. Wash......... .. ......... Smith Tower St. Lows, Mo...................................................... 4060 W. Pine Blvd. Tulsa, Oxla_...... ........ _...................................... .409 E. Archer St Vancouver, B. C---- -------- ---------------- 6865 Laburnum St. Washington, D. C--- -----------~_1101 Vermont Ave., N. W. ENGINEERS AND MANUFACTURERS Manufacturers of Copper and Stainless Steel,Badger Corrugated ExpansionJoints; Engineers and Manufacturers of Chemical Apparatus; Engineers on Process Work; Designers of Complete Plants. Years of experience in the design, manufacture and application of packless, corrugated expansion joints have brought the BADGER EXPANSION JOINT to its high state of efficiency and economy. Most recent developments emphasize the constant study Badger engineers are giving to expansion joint development: 1 . . . Application of Heat Treatment . ... scientific heat treatment is applied throughout the fabrication of Badger Expansion Joints with the result that the buyer gets all the benefits of this important metallurgical step. 2 . . . Directed Flexing . . . involving a new design corrugation and equalizing ring, resulting in much longer joint life. The allcurve Directed Flexing corrugation distri butes flexing stresses which, with straight-sided corrugations, tend to localize. ' 3 . . . Stainless Steel Joints . . . perfected after years of study and testing with this useful metal . . . now practicable to use the packiess type of joint for high tempera tures and high pressure conditions. The BADGER Expansion Joint is the packless type. Requires no servicing through out its long life. Ideal particularly for underground use or in cramped quarters. Wide range of traverse. BADGER Self-Equalizing, Directed Flexing, Expansion Joint Designed for traverses ranging from fractions to 6 inches single and 12 inches double; for pres sures ranging from high vacuum to 200 pounds (copper) and 300 pounds (stainless steel); and for temperatures ranging from sub-zero to 500 F (copper) and 900 F (stainless steel). List prices, in stallation and other data in Bulletin 100. BADGER Non-Equalizing Expansion Joint Designed principally for traverses up to (4 inch and for pressures up to 25 pounds; also good as the connecting element be tween adjacent equipment to absorb vibra tions or limited lateral displacements; standard shapes: round, oval, square or rectangular; special shapes to order. Bulletin No. 200. (See also BADGER Flexible Pipe Line Seal Designed to be used on pipe passing through walls, foundations or bulkheads, the purpose being to allow expansion and contraction but to seal the opening against seepage of ground or other waters. Bulletin No. 300. . igc W17) 1004 Heating Systems Specialties Cochrane Corporation 3130 North 17th Street, Philadelphia, Pa. Branch Offices in 40 Principal Cities />' COCHRANE HEAVY-DUTY *- . ' STEAM TRAPS ' A high pressure unit for condensate drainage of steam lines, separators, coils, evaporators, etc., and for conditions invol ving relatively high drainage rates. Rec ommended for pressures up to 400 lb. - Simple construction. No levers, con stricted passages or stuffing boxes to be come clogged with sediment or scale. All parts are readily accessible. Action is quick and. positive, avoiding wire drawing and erosion. Discharge capacities may be conveniently altered by easy change of valve seat. Write for publication No. 2850. COCHRANE MULTIPORT RELIEF VALVES For back pressure, atmospheric relief, flow or check valve service on air, gas, ' steam or water lines to give positive pro tection against explosions aris ing'.from stuck, jammed or over weighted valves. Differ in the usual construe-' tion in that a' number of small i' disks are used .; instead of one . large disk. For ; full description - write for publication No. 2870. Multiport Bock Pressure Voice . Bucket Trap MULTIPORT DRAINERS Of the multiport type, they afford un usual capacity for removing condensate or drips from purifiers, separators, jackets, radiators, pressure heating or drying coils, etc. Eliminating condensatedelivers maxi mum heat from steam production at lower cost. Tremendous capacity assured by large port areas. Provides continuous dis charge. Instantly responsive. Compact and light in weight. For pres sures up to 150 lb. ' Multiport Drainer ALL-SERVICE SEPARATORS Steam is rarely or never generated dry or clean and, in that state, corrodes turbine * blades, engine and pump cylinders, valves, pistons, etc. Exhaust steam contains oil and entrained solids which should be re moved to eliminate friction and wear. Cochrane Separators purify steam by separating out oil, slugs of water and con densate. Complete removal of entrain ment is accomplished by vertical baffle ribs which guide it into a direct unrestric ted fall, and a baffle area which extends far beyond the flow from the inlet pipe. Ports at the sides of the baffle prevent the puri fied steam from passing over the drip area and coming into contact with the entrain ment. The steam flow is uninterrupted arid pressure loss is minimized. All Service Separator . For information on other Steam Special* ties write for individual publications. 1005 Heating Systems Valves, Air The Dole Valve Company Main Offices and Factory: 1901-1941 Carroll Avenue, Chicago, 111. Branch Offices and Representatives In ail Principal Cities Dole No. 1A Vari-Vent Valve is designed to be part of a room- thermostat-controlled oil, gas or stoker fired gravity steam heating system. Vents air extra fast. Permits comfortable heating with lower and more economical boiler pressures. On systems using this valve throughout, all radiators are heated quickly with only ounces of pressure rather than the usual pounds. Also BALANCES distribution of heat to radi ators; gives definite straight-line control--any vent- ' ing speed between virtuallyclosedand wideopen. j|j Large and distant radia tors heat as rapidly as those close to boiler. Tamper-proof -- can be set and locked. Easily installed. Chromium finish. jYo. /.1 Vari-Vent Valve No. IB Vari-Vent Air Valve on each convector for BALANCING automatically fired gravity steam convector installations. No. 1C Quick Vent Float Valve for mains of automatically fired gravity steam installations. Valves at Right (top to bottom) No. 3 Air Valve for all types of gravity steam installations operated at any pressure up to 15 lb. Positive seal against water. No. 3C Air Valve, all purpose straight type. Particularly recom mended for unit heaters. No. 4 Quick Vent Valve, for mains ending 18 in. or more above boiler water line. No. 5 Quick Vent Valve. Positive seal against water. No. 2B VacuumValve for vacuumizing gravity steam installations. Valves Below (left to right) No. 14 Key Valve for venting concealed radiators and convec tors of hot water heating systems. No. 33 Air Valve. Low cost, No. 6B Vacuum Valve for quick venting main of vacuum- ized systems. No. 2B Vari-Vent Vacuum Valve for BALANCING vacuum- high quality and performance. ized gravity steam installations. Write the Dole Valve Company for a handy Selector Chart which indicates the Dole Air or Vacuum Valve most suited (or a particular need. 1006 Heating Systems % Specialties GRIN NELL COMPANY. . Heating, Industrial and Power Plant Piping, Fittings, Hangers, /> ' Valves, Pipe Bending, Welding, Piping Supplies, Etc. - :" : Executive Offices: Providence, R. 1. National Distributors of Thermoflex Traps and Heating Specialties For data on other Grinnell Products, see pages 944-940 Thermoflex Specialties Thermoflex High Pressure Traps The heart of all Thermoflex Traps is the Hydron Bellows. . The Hydron Bellows is formed under hydraulic pressure. This powerful internal pressure locates any weakness of any nature in the tubing. Such hydraulic pres sure is many times more severe than any pressure the Trap will ever be called upon to control. Every Thermoflex Trap, there fore, is practically indestructible. ' Thermoflex Traps have an exceptionally large orifice. This large orifice combined with high lift, insures fast action and The No. 100A Thermoflex Trap is guar freedom from clogging. anteed for steam pressures from 50-125 We supply Thermoflex Traps guarari- lb. Must not be used where the steam teed for steam pressures of 25 lb, ,40 50 lb temperature exceeds 400 F. and to 125 lb. Complete informatjbn and For use with all types of proces? work. details of typical installations will be gladly Laundry Machinery, Kitchen Equipment. sent on your request. Ask (or Catalogue . Hospital Sterilizers, Vu/canizers; pry on Thermoflex Heating Specialties. Kilns, Unit Heaters, Street Steam Ser.vide. Valves, Traps, Gauges, Etc. etc., in fact any place that a trap is desired for service at the above pressures. The Thermoflex line includes' Radiator Traps, Offset Traps, Blast Traps, Drip Traps, High Pressure Traps, Vent Traps, High-grade Packless Inlet Valves, and the Thermoflex Alternator, Thermoflex Com pound Gauge, Thermoflex Damper Regu lator. . No. 12 Small, compact and inexpensive. Extra heavy body. Renewable nickel steel seat and disc. Bellows made from special bronze tubing and encased in brass sleeve to prevent distort ion due to pressure. Regularly furnished without unions, plain nickel finish. Can be furnished with unions, polished nickel or chromium plated at extra cost. Thermoflex Radiator Trap No. 4 Thermoflex Drip Traps The full eight-fold Thermoflex-Hydron Bellows is guaranteed because of the Hydron-forming process. Body is heavy bronze construction throughout, with renewable seat. Fully nickel-plated with highly polished trimmings. The No. 12 is made in angle and in corner patterns, with 3^ in. inlet and % in. outlet tappings. The inlet neck is double thick to allow for expansion strains. Guaranteed for steam pressures up to 25 lb. Used for dripping mains, risers* coils and unit heaters. Semi-steel body, bronze cap and inserted renewable bronze seat, angle pattern only, without unions. Can be used for any general purpose where a finished, nickel-plated trap is not neces sary, and at a lower cost. Guaranteed for steam pressures up to 25 lb. 1007 Heating Systems vai.es Jenkins Bros. BRONZE - IRON - STEEL VALVES Mechanical Rubber Goods 80 Whitest., New York, N. Y.; 524 Atlantic St., Boston, Mass.; 376Spring St.. N. W., Atlanta, Ga.; 133 N. Seventh St., Philadelphia, Pa.; 1514 Fulton St., Chicago, III.; . ' 1112 Walnut St.. Houston, Tex. Bridgeport. Conn. (Office and Factory) 1 Jenkins.Bros.. Ltd.: London, W.C. 2; Montreal, Que., (Works and Main Office). IN VALVES ^ GIVES YOU EVERYTHING Heating Systems Specialties Kieley & Mueller, Inc. . FA Established 1879 Engineering Specialties for Pressure and Flow Control * 40 West 13th Street, New York, N. Y. ` Factory: NEWARK. N. J. Agents in All Principal Cities PRODUCTS--Valves: Altitude, Stop and Check, Pressure Regulating, Float, Pilot Reducing, Back Pressure, Tank Control. ' Liquid Level Controllers, Water Feeders, Pump Governors, Steam Traps, Y-Type Strainers. Also Damper Regulators, Hot Water Temperature Controllers, Oil Separators, Steam Separators, Return Traps, Water Columns, etc. Catalogs sent upon request Fig. 763 Bronze Regrind- ing String Check Fig. 106A Bronze Glebe, Renewable Comp. Due Fig. 613 Iron Body Regrinding Globe Fig. 634 Iron Body Remind ing String Check OVER 500 DIFFERENT JENKINS VALVES COVER EVERY HEATING AND AIR CONDITIONING NEED To adequately describe the complete Jenkins line of valves requires a Catalog of more than 300 pages. There are over 500 different types and patterns of valves that bear the trusted "Diamond" trade mark. Practically speaking, Jenkins can furnish any valve that you may require for plumbing, heating, air conditioning, general industrial or engineering service. ' General Classifications of Jenkins Valves Include--Bronze Valves fitted with Jenkins renewable composition disc. Bronze Regrind-Renew Valves with bevel and plug type seats. Bronze Gate Valves. Iron Body Valves fitted with Jenkins renewable composition disc. Iron Body Regrinding Valves. Iron Body Gate Valves with solid wedge and double disc parallel seats. All-Iron Valves. Cast Steel Gate, Globe and Swing Check Valves. Electrically and Hydraulically Operated Valves. Radiator Valves. Fire Line Valves. Quick-opening and Self closing Valves, Needle Valves, Y Valves, Solder-End Valves, Stainless Steel Valves. Other Jenkins Products Are -- Colored Valve Wheels with or without service markings molded in relief letters. Composition Valve Discs exactly suited to service conditions. Sheet Packing. Gas kets. Moncrieff Scotch Gage Glasses. JENKINS VALVES ARE SOLD BY GOOD SUPPLYuHOUSES EVERYWHERE 1008 Pressure Regulating Valve Spring and lever weighted valves for all services and for initial pressures up to 250 lb and reduced pressures from 0 to three- 3uarters of the initial pressure. Single or ouble seated in sizes % to 16 in. Suitable for steam, water, air, oil and gas. Con trolled by a small feeler pipe connected from diaphragm to low' pressure side. Back Pressure and Atmospheric Relief Valve For use where plant is operated either con densing or non-condensing. Outside air dash pot insures noiseless operation. Maintains exhaust line back pressure from 0 lb to 25 lb. Made horizontal or vertical lever and weight or spring operated. Steam Traps Large capacity, small sized inverted bucket traps; quick acting, self-cleaning and nonvair bind ing. Sizes % to 2 in. Pressures up to 250 lb. Body and cover, semi - steel. Valve and seat, stainless steel. Re movable cap allows inside inspection or replacement of . valve parts without disturbing pipe connections. (AH parts are interchangeable). For the accurate control of liquids in tanks or other vessels; suitable for use in in dustrial] plants, gasoline plants, refineries, etc. Direct connected or remote control; ball bearing spindle and easy-to-pack stuffing box; rotary or sliding valve. Write for special bulletin C-3. 1009 Heating Systems Specialties Mueller Steam Specialty Go., Inc. 40-20 22nd Street, Long Island City, N. Y. Steam, Water, Air, Oil and Gas Specialties for Heating and Power Plants Pressure Reducing Valves--Straight Pattern and With Increased Outlet No. 11--For Vacuum, Vapor and Low Pressure Heating Systems. Initial Pressures, up to 200 lb; Reduced Pressures, 0 to 10 lb. No. 17 and 21--For automatic control of reduced pressures on dead-end service, requiring a tight closing valve, such as tank heaters, kitchen utensils, sterilizing ap paratus, laundry equipment, kettles, cookers, driers, etc. Initial Pressures up to 200 lb. Reduced Pressures 0 to 150 lb. ... Constructed with full globe bodies. Center guide eliminates the wings on discs, and increases efficiency, assures minimum noise and prolongs the life of the seats and discs. Lever and weight operates on a steel roller bolt, assuring a most sensitive valve. Spring type furnished with special long springs for sensitive operation and wide ranges of reduced pressures. Automatic Water Feeders With a powerful leverage to control the water line in steam boilers, etc. They supply make-up water to compensate for evaporation, leaks, steam utilized in process work and condensation wasted. Where condensation held up in the system eventually returns in large No. St7--Duflex quantities, our Duplex type protects Up to tSfiOO &) Ft. tne boiler against flooding. All working ... ,600 Sq / . parts of non-corrosive metal, are accessible without breaking pipe connections. Provided with an integral strainer. For steam pressures up to 100 lb, water pressures up to 120 lb. Equipped with low water and pressure Mercoid Tube Switches for all services. Steam Traps Simple, Sturdy and Compact Ball Float and Inverted Bucket Steam Traps for draining water of condensation from steam apparatus and steam mains. Powerful leverage enables them to take care of large quantities of condensation. Bali Float Steam Traps equipped with integral strain er, water gages, air cocks, blow-off ana integral by-pass valve, when desired. All working parts are ac cessible without disturbing Boll Float No. t!9--Up to SO lb. No. ttl-Up to 160 ft. Size* H to S in. any pipes. Valves are sealed with sev eral inches of water, making theescapeofsteam impossible. Inverted Bucket No. tit--For Prenvfftt Up to t60 lb. Siut V6 to t in. Catalogue and Bulletins covering our Complete Link gladly furnished on application. 1010 Heating Systems Specialties Wright-Austin Co. 317 West Woodbridge St., Detroit, Mich. PRODUCTS--Steam Traps, Strainers, Air Traps, Steam and Oil Separators, Compressed Air Purifiers, Exhaust Heads, Boiler Feeders and Controllers, Alarm Water Columns, Water Gauges, Trycocks. "Airxpel1* Bucket Type Steam Traps Are "double duty" traps, because they automatically discharge both air and condensate. Union connections make them easy to connect up. Also, furnished with screw con nections when desired. They save money for fittings and instal lation labor, by having straight through horizon tal pipe connec tions. The Cub sizes are made in A. in., M in., 1 in. Especially suitable for in dividual unit drainage on heating and process equip ment. Also three "Master" sizes x/l in. to 2 in., for general service. "Emergency" Float Three valve trap with large capacity at high pressures. An ex ceptionally reliable trap for use in inac cessible places. Steam Trap Air Relief Trap For relieving air from forced circulation hot water heating systems, water supply lines, closed tanks, receivers, pumps, etc. May be used two ways-- as a straight-way or angle _ strainer, in either hori- 2 zontal or vertical pipe I . line, because it has the ^ choice of two inlets at right angles to one another. For cleaning, flush through blow-off connection, or remove screen by unscrewing bottom plug. Separators--Steam and Oil Type "A" Vertical Type "S" Steam Horizontal Oil "Combination" Steam Trap Float Type with internal thermo static air bypass and strainer. A modernly design ed and very suc cessful trap for vacuum and pres sure heating. "Victor" Low Pressure Steam Trap A heavy duty trap for large volumes of con densation at low pressures. We make separators of every type and all sizes for all pressures. Exhaust Head Designed to eliminate noise and spray. Three types to select from--the "Cyclone" Heavy Duty, and Standard Galvanized Steel--also, the cast iron type, to remedy all condi tions. Sizes 1 in. to 48 in'. Send for descriptive Bulletins on any of the items listed on this page. 1011 Heating Systems' Specialties Yamall -Waring Company Manufacturers of Steam Specialties 7600 Queen Street, Philadelphia, Pa. YARWAY IMPULSE STEAM TRAPS Construction--The Yarway Impulse Steam Trap is unique in that there is only one moving part, the simple valve F. This trap is made of bar stock throughout, no castings used. Body and bonnet of A--Cap Nut -B--Lock Nut | C--Bonnet S--Lock Pin r--Volte K--Control Chamber D--Control Cylinder L--Cenlrd hire . G--Volte Seat H--Teel Plug J--Soiv cold rolled steel, cadmium plated; cap of tobin bronze, valve and seat of heat treated stainless steel. For pressures 400 to 600 lb, bonnet and cap are stain less steel. Operation--When handling conden sate, pressure required to lift valve F is greater than reduced pressure in control chamber K; therefore, valve F opens, allowing free discharge of condensate. As remaining condensate approaches steam temperature, flashing takes place, flow through center orifice is choked and pressure builds up in control chamber K,. closing valve F. Advantages Light Weight--Yarway traps need no support--Vi in. trap weighs only 1 54 lb. 2 in. trap weighs 854 lb. Small Size--They practically eliminate radiation losses--can be installed in cramped quarters--56 in. trap measures 254 in. long--2 in. trap, 454 in. long. Will not air bind. Require no priming. Insure quick healing. Operate on exclusive Impulse principle ( U. S. Patents No. 2,051,732 and2,127,643.) Loin Price--Often cheaper than re pairing old traps. Factory set to operate at all pressures up to 400 lb (or 600 lb) without change of valve seat. Prices, Weights and Dimensions Size In. vf V. 1 I1/. I'A 2 Trap No. Prices . 4001b 450 F 6001b i 600 IE~ -- Trap 550 F ! 750 F Complete 60 61 63 64 . 66 67 70 , 120 71 121 73 1 123 74 124 76 ! 126 77 127 $15.00 22.00 31.00 48.00 68.00 90.00 Wt Lb m 2 2Va 4 6 8% For further information send for descriptive bulletin T-1734. YARWAY GUN-PAKT EXPANSION JOINTS ' All-steel welded construction; light but strong. Chromium covered sliding-sleeves. Cylinder guide and stuffing box integral, assuring perfect alignment. Internal limit stops. Gun-pakt and Gland-pakt types; Gun-pakt (illustrated) fitted with screw guns which permit insertion of plastic packing while joint is under ; pressure. Sizes 2 in. to 24 in., single end or double end, flanged or welding ends; 150, 300 and 400 lb pressures. For additional details send for bulletin EJ-1906. 1012 /> INSULATION m. Many different materials are used for insulating purposes--in their natural, state or processed and fabricated into various forms. They include; Vege table fibers, wood, tree bark, cork--processed into wools or other fibrous forms, and used in loose bulk or fabricated into boards, paper, blankets or batts. Natural wools, jute, hair--felted into blankets, pads, mats, etc., or used in loose bulk forms. Mineral products such as natural rocks and furnace slags--processed into granulated form, or into wool form and used in loose bulk or fabricated into blankets, batts, or pads; and asbestos, asphalt, gypsum and magnesia--used in board form, blankets, felts, or in loose bulk. Many of these types- ofinsulation are also used in plastic form. Metallic insulation, such as aluminum and steel are fabricated into sheet form and used separately or in conjunction with other insulating materials. INSULATION, Underground (p. 1014-1017, 1030-1031) Asbestos, asphalt, mineral wools, magnesia--used in conjunction with underground piping and conduits of concrete, tile or cast iron. . Technical data is contained in Chapter 40. *-f. INSULATION, Pipes and Surfaces (p. 1025-1050) Asbestos, magnesia, and mineral wools in loose fibrous forms, blankets, or in plastic forms and suitable for use in extremes of high or low temperature service; also hair and felts, and cork in loose bulk or in molded or plastic forms. ' Technical data will be found in Chapter 40. . Some of these insulating materials are also used as refractory materials. INSULATION, Duct (p. 1023-1051) Various of the insulating materials which may be fabricated into board or slab forms, and various felts and fibrous materials have been adapted, for use as duct insulation-- as a duct liner or applied to the outer surfaces. Some have been utilized to construct the walls of the duct itself, serving the dual purpose of duct and insulation. Technical data is contained in Chapter 40. INSULATION, Window (p. 1018*1023) ; Single-pane and double-pane insulating window sash, metal fabric insulating window screens, weather stripping for windows and for interior and exterior doors. INSULATION, Building (p. 1023-1051) Aluminum sheets, paper in sheets and fabricated forms, felts, cork,, glass and rock wools, cane fibre boards, wood products in board form and fibrous blankets and pads, or used in loose fibre form--all are utilized.as insulation against heat or cold. Technical data on this type of insulation will be found in Chapter 5. . Insulating materials, in board or slab form are adapted for use in walls as a plastic . base, and thus serve as both a heat or cold insulation and a fire-retarding material. INSULATION, Sound Deadening (p. 1023-1051) Many'of the insulating materials utilized in building.construction are also suitable for sound deadening or acoustical control. Some of them are also adapted for use on machinery and in building to counteract or absorb vibration. . . Technical data on Sound Control will be found in Chapter 3L - i; Manufacturer's products shown in this division are designed for specific applications. Consult the Index to Modern Equipment for additional products of these manufacturers. 1013 Insulation Underground Adsco PRODUCTS for STEAM SERVICE American District Steam Company North Tonawanda.N.Y. IN BUSINESS OVER SIXTY YE/\RS Branches and Agents in Principal Cities Tile Conduit a-illt Asbestos Insulation COMPLETE SPECIFICATIONS AND BUYING INFORMATION ON ADSCO PRODUCTS FOR STEAM DISTRIBUTION IN THE ADSCO CATALOG No. 35 Complete within one book, the ADSCO Catalog No. 35, are all the data required for the specification or purchase of equip ment for underground or surface steam or hot water lines. The catalog contains over 136 pages of illustrations, dimensions, and other data on ADSCO Slip Type and Packless Type Expansion Joints, Tile Conduit and Wood Casing for underground steam or hot water lines, pipe supports, alignment guides, pipe anchors, saddle plates, condensation and steam flow meters, steam traps, storage and instantaneous water heaters, etc. Tile Conduit with ADSCO-Fiberglas Insulation Red Diamond Brand Wood Casing Internally Guided Joint ADSCO Products Illustrated Illustrated at the left is ADSCO-Bannon Tile Conduit and base drain with ADSCOFiberglas Filler Insulation and with sec tional asbestos insulation. The material is available in sizes from 4-24 in. for one or more pipes and is salt-glazed, vitrified tile conduit made by a pioneer manufacturer of steam conduit. It is economical in cost, easily installed and an ample supply is maintained for prompt shipment. Two popular types of ADSCO Slip Ex pansion Joints are illustrated at the left. The ADSCO InterriallyGuided Expansion Joint has an internal guide ring on the inner end of the slip. It is compact in size and available in semi-steel, cast or wrought steel for high pressure and high tempera ture service. The ADSCO InternallyExternally Guided Expansion Joint is similar in construction, plus an external guide in. the two-piece, removable hood which protects the slip from dirt ordamage. These and other types of ADSCO Expan sion Joints are fully described in the ADSCO Catalog No. 35. Internally-Externally Guided Joint Write for ADSCO Catalog No. 35 Every consulting engineer, engineers in public utility companies, industrial plants, colleges, institutions, railroads, and federal, state or municipal departments should have a copy of the ADSCO Catalog No. 35 for the useful data it contains on depend able steam distribution equipment. Write for your copy today to Department G. (See also Page 1000) 1014 Insulation Underground H. W. Porter & Co. INCORPORATED ; Newark, New Jersey 0$ - Permanent Protection and Insulation for Underground Pipe Lines BALTIMORE, MD. CHARLOTTE, N. C. RICHMOND. VA. WASHINGTON, D. C. *CG VS f>drOfr STEAM CONDUIT SYSTEMS For Central Heating--Therm-O-Tile is a complete conduit system for the per manent support, protection, and insulation of underground mains of a central heating ter, and with 5 different size base tiles they produce 27 different conduit cross sections. Foundation--The base of die system is a thick concrete slab poured directly in the trench bottom, reinforced with steel when installed over a filled or boggy ground. Drainage--The drainage system of the conduit is entirely internal, open to in spection at manholes, and of ample ca pacity to keep the pipe space dry at all times without any possibility of becoming clogged with silt or vegetation. Insulation--Either sectional pipe cov ering or Thermobestos waterproof fibre filling may be used for insulation, as the insulation space is kept dry at all times, by the internal drain. For single or double pipe lines, sectional insulation of econom ical thickness is recommended; for multiple pipe lines, a filler type of insulation is usually more economical in first cost. Pipe Saddle. Permits full thickness of insulation between pipe and roller. Waterproofing-- Under normal soil conditions, this conduit is waterproof. If marshy ground or partially submerged conditions are encountered, the conduit may be made completely waterproof by the use of membrane waterproofing applied under the slab on a sub-base and carried completely over the tile envelope. Anchor Block. Fils directly in line with Base Tiles. Efficiency--The degree of thermal efficiency secured depends upon the type and thickness of insulation used. This conduit, due to its sealed air chambers in the tile and dry insulation space, adds to the normal efficiency of the insulating material on the pipe lines. Pipe Support for Single Pipe. . Pipe Support for Three Pipes. Representatives--Therm-O-Tile is also sold and installed locally by Johns-Man- ville Construction Units. Pipe Support--All pipes are supported on cast-iron adjustable supports resting directly on the concrete base independent of the tile envelope. Accessibility--All piping is installed before tile is placed, giving complete ac cessibility for welding, testing and insu lation. Pipe fitters work on concrete slab "walkway/* Strength--Due to immovable concrete base and arch construction of extra heavy tile members, conduit will sustain any roadway traffic load usually encountered without extra reinforcement. Single or Double Pipe Lines Using Sectional Pipe Insulation. Multiple Pipe Lines Using Filler Type Insulation. 1015 Insulation Underground The Ric-wiL Company Agents In Principal Cities Established in 1910 CONDUIT SYSTEMS FOR UNDERGROUND STEAM PIPES Union Commerce Bldg., Cleveland, Ohio New York, Chicago, San Francisco . Conduit--Standard conduit is vitrified salt glazed tile or cast-iron with Loc-liP Side Joints, bell and spigot type, lined or unlined. Tile in 24 in. sections, sizes 4 to 27 in. inside diameter. A Super-Tile conduit to support any average traffic load is also available. For extra heavy duty under rail roads or where conduit is subject to extreme loads, Ric-wiL is made of cast-iron in 2 or 4 ft sections. For a labor-saving system Ric-wiL Insulated Pipe Units are ideal. Where reduced labor cost is not essential; Ric-wiL Universal Type System is recom mended (details on request). Base Drain--Standard Base Drain is vitrified salt glazed tile for tile conduit and extra heavy tile or cast-iron for the castiron conduit, in 24 in. lengths. Made in three sizes to support and drain properly all conduit sizes. Pipe Supports--Standard pipe sup ports will carry from one to five or more pipes and are ordinarily spaced 12 ft apart. They are strong, made of cast-iron, rustproofed, and interlock with the base drain foundation, imposing no load on the con duit itself. No movement of pipes can disturb them. Special pipe supports avail able for different conditions. Information on request. Insulation--Ric-wiL Dry-paC Water proof Insulation is high-grade long fibre asbestos processed so that it is permanently water repellant. Of unusually high efficiency and great natural strength, it w ill not slump away from pipes and is non corrosive. Sample will be sent gladly for testing. Ric-wiL No. 11 Insulation (same as Dry-paC except non-waterproof) or sectional pipe covering can also be fur nished. For lined conduit, diateomaceous earth mixture is molded and keyed inside the tile. Accessories--Shutter sleeves, alignment guides, filter cloth, manhole covers, and other accessories furnished as desired. Engineering Service--Full coopera tion with architects and engineers. In stallation supervision if desired. Technical Data--Tabulated Steam Heating Rates, Test Reports, Service Detail Bulletins, Catalog Bulletins, Central Heating Bulletins and Architects and En gineers Detail Sheets available on request. Piping Above Surface and Underground I E. B. Badger & Sons Co. General Office: 75 Pitts Street, Boston, Mass, through its subsidiary company Underground Steam Construction Co. PRODUCTS--Contracting of Steam Line Installations. High Pressure Power Plant Piping We are widely experienced in the in stallation of piping systems of all kinds, including high pressure power plant lines and overhead steam lines. Wo shall be glad to quote on any work of this nature in your plant. Underground Lines We have an experienced construction force to take over any phase of installa tion of underground steam lines. Some important jobs have been near bulkheads where salt water seepage was a problem. Others have been in rural areas where rugged terrain presented many obstacles. f Piping connections for pumping units f l Ric-wiL Insulated Pipe, a prefabricated, ready-to-install unit, in standard lengths including asphalt-coated conduit (Armeo Iron), pipe, insulation, and accessories. Ideal for speed and economy on district heating project*. Poiver plant boiler connections (See also Page 1004) 1017 Insulation Weather Strips Chamberlin Metal Weather Strip Co., Inc. General Offices, Detroit, Mich. Factories, Detroit, Mich., Peru, 111. Factory Sales- Installation Branches Atlanta. Ga. Baltimore. Md. Boston. Mass. Buffalo. N. Y. Chicago. III. Cincinnati. Ohio Cleveland. Ohio Dallas, Texas Denver, Colorado Detroit. Mich. Indianapolis, Ind. Kansas City. Mo. Los Angeles. Cal. Louisville. Ky. Milwaukee. Wis. Minneapolis. Minn. Newark. N. J. New Haven, Conn. New York. N. Y. Philadelphia. Pa. Pittsburgh. Pa. Portland, Ore. Providence, R. I. St. Louis, Mo. San Francisco, Cal. Schenectady, N. Y. Washington, D. C. CHAMBERLIN HEAT-SAVING PRODUCTS Weather Strips, Calking, In-Dor-Seals, Insulation and Insulate-Windows. Weather Strips Modern weather strip service, in which engineers and architects can have greatest reliance, is one that can responsibly fulfill conditions of a contract. For problems of infiltration or circulation of air, gases or mixtures, leakage of rain, filtration of dust, sand or soot--there's a Chamberlin Weather Strip remedy regardless of cli matic or construction conditions. Particu larly helpful to the engineer is the know ledge that the job can be entrusted, regardless of location, to a Chamberlin Factory Branch employing experienced mechanics. .. Modern problems of heating, venti lating and air conditioning can be ap proached with utmost confidence in this field with the aid of Chamberlin's proven 46 years of experience and specialized training. Write for A.I.A. catalog of standard details and specifications. Con- suit nearest branch for equipments, sur veys, quotations. ss Oldest and most extensively successful weather strip Principle--tongue in groove. SO to 95 per cent efficient. No failure or upkeep. Calking Chamberlin Plasti-Calk is essential in the sealing of construction joints in wood, metal, glass, stone, tile, concrete and brick. It. is waterproof, permanently elastic, non staining and noncorrosive. It provides durable adhesion and will not sag, pucker, or shrink under extremes of heat or cold, dryness or moisture. Chamberlin PlastiCaik is specially prepared with porous pigments capable of retaining oil indefi nitely, and does not contain tar or asphalt. Supplied in various colore. It is all impor tant that a calking compound be specified thoroughly on thebasis of stringent physi cal properties. Such specifications will be furnished upon request. Calking applied with hand tools, hand or power gun. Crack closed when door is latched. Automatic Door Bottoms In-Dor-Seals eliminate under-door drafts and heat losses in rooms adjacent to cold areas, corridors and halls--as in a sleeping room door--virtually an "outside" door at night when windows are open. They are used to light-proof X-Ray and dark rooms; to sound-proof private offices, studios, laboratories; to resist room-toroom circulation of odors, fumes and dust. 1018 raised | Felt Strip |--aut o- matically the itislant door opens. Insulation . Chamberlin Metal Weather Strip Co., Inc. General Offices, Detroit, Mich. Factories, Detroit, Mich., Peru, 111. ' CHAMBERLIN HEAT-SAVING PRODUCTS Weather Strips, Calking, In-Dor-Seals, Insulation and Insulate-Windows. Rock Wool Insulation Having an average conductance coef ficient oi 0.24 to 0.27 Btu, Chamberlin Rock Wool is one of the most efficient insulations available today. Long in fibre and clean of "shot", it insures effective insulation with low density and light weight. It is available in several forms adaptable to both new and existing con struction--in blowing, commercial or loose wool fibres; in wall-thick or 2 in. thick batts, with or without vapor-proofing coverings. Among its physical properties Chamberlin Rock Wool averages . 38 per cent silica, 32 per cent lime and only 0.04 per cent sulphur. Its loss on ignition is less than 0.1 percent. Wherever pos sible pneumatic application, by means of such modern high-powered and efficient transient units as illustrated, is preferable. Here again, the engineer will do well to consider the value of faithful, responsible performance in the art of application-- the hidden factor that means so much in obtaining the utmost efficiency from insu lation. Insulate-Windows In addition to other major heat loss controls, Chamberlin has developed a pro duct that reduces 40 to 60 per cent of the heat loss of glass in standard window con struction. Thousands of Chamberlin InsulateWindow (registered tradename) units have been applied to wood and metal windows in existing buildings, including offices,. banks, residences, etc.; they are not double glazed units. They are single glazed and custom made to supplement existing win dows of practically any type. Depending upon characteristics of the areas and sash to be "insulated," Insulate-Windows are hinged, stationary or sliding. They are . framed with a patented rolled section of antique-finished, cold-rolled bronze em bodying ingenious features of mechanical glazing in place of putty. Chamberlin "insulation" of windows is a high grade, mechanical service involving design and installation of durable, secondary window units, readily accessible for cleaning and removal when necessary--no interference with sash operation or ventilation. Insu late-Windows provide a year 'round heat stop that gives practical relief without the technical difficulties involved in doubleglazed windows. Typical Chamberlin Insulation unit. Equipped with Powerful.gas-powered.pneumatic blower capable ofpro jecting granular grade "A " rock wool a minimum dis tance of more than gOO ft through a large rubber hose. At right--near view of ' ` insulated" residential metal casement windows. Chamberlin Insu late-Windows on outside. Below-- battery of Insulate- . Windows showing how they can be hinged. All6 units can be unlatched from within the room by simply opening the two casement venti lators. . Sec Chamberlin exhibits in The Home Building Center of the New York World's Fair. 1019 Insulation Windows Libbey-Owens-Ford Glass Gofnpany Toledo, Ohio THERMOPANE Metal Sealed Insulating Units Double-Glass Insulation in a new. Highly Efficient Form--Two panes welded into One Metal-Sealed Unit, to be glazed in a single sash. Sales Offices in Principal Cities Thermopane--two panes of glass, with an air space between, sealed with metal-- provides efficient insulation for glass areas. Practically any type of flat glass may be used in Thermopane. It may be made up of two sheets of glass of identical type, such as two sheets of Plate, Window or Figured Glass, or one light may be clear and the other figured. Again, to meet certain summer heat conditions, the outer light might be Aklo Heat-Absorbing Plate Glass and the inner light either clear or obscure. Generally speaking, the types of glass that are practical with Thermo pane are limited only by the types of glass available and the particular problem in volved. With Thermopane, the heating engineer and architect have available an excellent means of insulating large areas without sacrifice of vision. Where privacy is desired or diffused light an essential, fixed walls or partitions. Thermopane insulates the year round--it keeps heat inside in winter, outside in summer. WIDE SELECTION OF-----THERMOPANE FABRICATIONS Generally speaking, the design effects obtainable with Thermopane are limited only by the types' of flat glass available. Thus any combination of D.S.A., Polished Plate, Colored Plate, and any of the various Figured glass is practical. . Cross section of Thermopane sample tUttsiroXmg the metal seal and the dehy drated air space betweenthetwo panes of glass. CONSTRUCTION--A single Thermopane unit con sists of two panes of glass separated by an air space which is hermetically sealed at all edges with metal. The glass used in Thermopane for exterior use ranges from Double Strength A Quality to 14 in.; %6 in. and K in. Polished Plate Glass, with a standard K in. air space. For interior use, the air space Thermopane was used very effectively in this picture window to insulate may be either in. or H in. a large area both winter and summer. The air space between the two mirror-clean lights of glass is dehydrated and her Thermopane again fully solves the prob metically sealed with a metal band at the lem. In addition. Thermopane may be set factory--thus dirt and condensation with in movable or sliding sash to eliminate in the air space are avoided. 1020 i Insulation Windows Libbey-Owens-Ford Glass Company Toledo, Ohio. Sales Offices in Principal Cities THERMOPANE SIZES--Thermopane is available in exceptionally large sizes ranging up to 72 in. x 96 in., depending upon the type of glass used. Following are the maximum and minimum dimen sions for each type of glass: . Maximum . .. Wide Long D.S.A. and Vi in- Polished Plate.......... ............... . .... 30 in. x 60 in. $ in. sheet or Polished ' Plate.....................................48 in. x 72 in. </4 in. Polished Plate........... 72 in. x 96 in. Minimum 8 in. x 8 in. 12 in. x 12 in. 12 in. x 12 in. The maximum and minimum dimensions apply equally to Figured glass. Thermopane is not available in single strength glass. THERMOPANE THICKNESS --To arrive at the thickness of Thermopane, add the air space thickness to the thickness of the two panes of glass. A plus tolerance of Y2 in. fr in. and thinner glass and a plus tolerance of He in. for glass over Y in. thick shall be allowed over the specified thickness. EDGE TOLERANCE--Obviously Thermopane is only available in stock sizes or special sizes to order. In listing cutting sizes, figure Y in. shorter and narrower than the opening size for lights, up to 24 in. square. Above 24 in., for any dimension, the cutting sizes should be ^16 In. under the opening size. SASH SIZES AND WEIGHTS--Be cause Thermopane is heavier than single glass, allowance for greater sash balances must be made in double hung sash. (See detail for weight). Rabbet Width Dimensions: To insure coverage of the edge construction, rabbet widths for lights under 24 in. for any di mension should be Y$ in. For lights over 24 in. for any dimension, the width should be J46 in. to Y in. Rabbet Depths: This dimension should not be less than 1 in. for Y in. air space and Yg in. thick glass. Somewhat more shallow rabbet dimensions can be success fully used, however, if the bright copper color of the metalized edges are allowed to be partially exposed to view. Increase the rabbet depth correspond ingly for thicker glass. (See detail.) TECHNICAL DATA AND ASSIS TANCE--If you have a special problem on which you require more complete information, write to the Architectural Service Department, Libbey-Owens-Ford Glass Company, Toledo, Ohio. FULL-SIZE THERMOPANE INSTALLATION DETAILS MAY BE .APPLIED TO'ANY WOOD OP METAL SASH OP DOOP . GLASS Iff '/" GLASS '/: GLASS GLASS WEIGHT BOTH PA>*S-J2 SISOR ALLOW A-AT EACH END fO* SIZES UNCE? JO NCXS ALLOW f,` JO A! EACH END fCB SIZES OVEf INCHES Insulation Screens Ingersoll Steel & Disc Division Borg-Wamer Corporation 310 So. Michigan Ave., Chicago, Illinois Distributors in the Principal Cities INGERSOLL- * A Metal Fabric That Screens I Windows Against Solar Heat . . . Reducing the Cooling Load KOOLSHADE contributes four important advancements to summer air conditioning: (1) It reduces the cooling load by stopping up to 81 per cent of the Solar Heat outside the window glass. (2) It forestalls complaints by minimizing extreme sun load conditions especially in severely exposed rooms. (3) It provides automatic shade .. . non-adjustable and free from the uncertainties of the human element. (4) It maintains lower temperature in non-cooled rooms. KOOLSHADE does this by stopping the direct sun rays before they strike the window--as illustrated below. / ---t- --h- Actual size photo showing visibility thru KOOI.SHA OE as superior to 18 mesh screen. It's all a matter of angles and spaces: KOOLSHADE is made of horizontal flat bronze strips woven together every half inch vertically with bronze wire. The horizontal strips are held at a FIXED angle of 17 deg, with the indoor edge higher than the outdoor edge. Attractive in appearance when instal led. Clear vision. Gives sun exposures the effect of soft "north light." Strong and enduring. Made in widths up to 72 in. Low in first cost and main tenance. c For Full Information, write for our Brochure HG100 "It's Cooler in the 1 Shade." Trade Mark Automatic Shade! Acting tike a mini ature Ventian Blind, KOOLSHADE fully stops the direct heat rays when the sun is 40 deg or more above the horizon--which means in the heat of the day in all seasons. Sim heat is kept outside the room--but cool, softly diffused light abundantly enters. FIXED adjustment; needs no attention. Framed and installed- like ordinary full length insect Screens--(and keeps out the insects too! SOLAR RADIATION TRANSMITTED THROUGH SHADED WINDOWS Atcntnffi tn Use Sun Load 22 Per Cent to 28 Per Cent Outside Venetian Blind or Shutter Sun Load 22 Per Cent Inside Venetian Blind Sun Load 58 Per Cent Half-Drawn Shade Sun Load 68 Per Cent 1022 KOOLSHA DE SUN 1.0AD W PER CENT Insulation Aluminum Aircell Insulation Co. Curtis Bldg., Detroit, Mich. INSULATION FOR INSULATION FOR 'S-Air Conditioners Brooders Buildings Chicken Houses Dairy Barns Fruit Storage Homes Hot Houses Incubators Refrigerated Rooms Licensed under Patents: 1,757,479--1,890,418--1,934,174 others pending Automobiles Beehives Busses Floral Shipping Boxes Heaters Ovens Ranges Shipping Containers Trailers . Trucks Heat Transmission Btu/Hour/sq ft/F Reflect-O-Cell Saves per cent Not 1 layer 2 layers 1 layer 2 layers Insulated Reflect-O-Cell Reflect-O-Cell Reflect-O-Cell Reflect-O-Cell Wood Stud Wall--4 in. studs......................... 0.26 0.13 0.09 50 65 Open Attic Floor................{............................. 0.69 0.19 0.12 69 82 Wood Shingle Roof (no lath and plaster).. 0.56 0.16 0.10 68 81 Thermal Efficiency determined at the University of Detroit under humidity conditions prevailing' in actual use and also at the University of Toronto, Toronto, Canada. REFLECT-O-CELL is the modern insu lating material based on the famous Dewar Principle of insulation, the outstanding example of which is the efficient Thermos Bottle. Light in Weight, not depending on thickness nor density, REFLECT-O-CELL employs this Dewar Principle by means of its polished Aluminum Foil backed by corrugated Hermetex paper. (Hermetex paper was formerly used ALONE^as an insulator by leading refrigerator manu facturers). The Structure of Reflect-O-Cell per mits both surfaces of the foil to reflect radiant heat. Moisture Sealing, which effectivelyreduces summer dehumidifying load and winter humidifying requirements by pre venting vapor pressure losses. Windproofing all studding spaces simi lar to metallic window weatherstrip effect. Soundproofing provided by high hys teresis air cell construction. Especially Indicated for exposed appli cation to eliminate air-conditioning shock and to reduce cooling load. REFLECT-O-CELL is used in the pro duction of insulated Buses, Trucks, Trail ers, Ranges, Heaters and others. Similar satisfactory service has also been rendered in residences, industrial buildings and pro cessing equipment. REFLECT-O-CELL is supplied in con veniently scored continuous Roll Sheets or in Packs and is easily installed between wall studs, ceiling joists and roof rafters by stapling through its flanged edges. Weighs only 38 lb per 1000 sq ft. Single layer wall application. Also installed in two layers. 1023 Insulation American Hair & Felt Company Established 1865 Merchandise Mart, Chicago Chicago Louisville ' Factories and Offices: Detroit Milwaukee Newark Peabody Wilmincton Los Ancbles Philadelphia INSULATING FELTS for Air Condi- Tank Cars, Automobiles, Busses, tioners, Air Ducts, Buildings, Cold ACOUSTICAL FELTS for Sound Ab- Storage Rooms, Pipe Insu- sorption, Sound Dampening, iation. Railroad Passenger and Refrigerator Cars, Refriger- O/l te Vibration Dampening. CUSH1 IONING FELTS for Shock Ab ators, Refrigerated Trucks, sk Muifsorption and General Cushion Shipping Containers, Tanks, '' inginlndustryandintheHome. Cattle hair is the oldest of all materials used' for insulation purposes. It is nature's own insulation and lasts indefinitely without decaying or deteri oration. American Hair & Felt Company have been manufacturing and selling hair felt insulation for 75 years and today our products are recognized as a standard by which other similar products may be judged. INSULATING FELTS This includes products such as Ozite Duct Insulation and other materials. Made in a variety of qualities, thicknesses and weights to suit every particular purpose--with various coverings, such as reinforced asbestos paper, Sisalkraft paper, black waterproof paper, muslin, etc. Weight per cubic foot of insulation varies from 2 to 834 lb. Thermal conductivity of hair felt according to Bureau of Standards'-tests is^.25 Btu's per sq ft, 1 inch thick, per degree difference F.--however the insulating efficiency of many of our hair-felt products is considerably greater than this standard. Hair is fire-resistant and even complete immersion in water will not affect its physical structure--after years of use it still has a high salvage value. Hair felt insulation comes in bales, rolls, sheets or cut to specified sizes and shapes. Rolls may be had in any width up to 108 in. by 50 ft long. ACOUSTICAL FELTS Specially developed hair felt products, including Ozite Duct Lining, for the elimination of noise in air conditioning systems and for all other sound correction purposes. In one of our newest products, FELTWOOD, finest wood veneers are bonded to a backing of hair felt to provide both thermal insulation and sound deadening properties while beautifying the interiors of homes, offices, airplanes, railroad cars and motor busses. FELTWOOD is a finished material, easy and inexpensive to apply. . We invite engineers to discuss with us their problems of insulation, sound correction and cushioning. Samples and full information about hair felt insulation products will be gladly sent on request. . 1024 Insulation Armstrong Cork Company Buildtng Materials Division t Lancaster, Pennsylvania Albant Atlanta Baltimore Boston Buffalo Charlotte Chicago Cincinnati Cleveland Columbus Dallas Des Moines Detroit Houston Branch Offices Indianapolis Jacksonville Kansas Cm Louisville Milwaukee Minneapolis New York Omaha Philadelphia Pittsburgh Richmond Rochester St. Louis Washington, D. C. Distributors Appleton, Wb. Northwestern Asbestos and Cork Insulation Co. Boston, Mass.______________ __ T. R. Nunan Company Charleston, W. Va---------- Capital City Supply Company . Cleveland, Ohio..-___________ Clark Asbestos Company Denver, Colo___ Stearns-Roger Manufacturing Company Eau Claire, Wis._____ _________ Horel-George Company Fort Watnb, IndAsbestos A Asphalt Products Co. Jamestown, N. Y____ .Laco Roofing A Asbestos Company Joplin, Mo.____________ ______ Joplin Cement Company Kingsport, Tenn______ I________ Kingsport Lumber Co. Little Rock. Ark.__Fischer Cement A Roofing Company Lob __AngelesjCalip _______Van Fleet-Freear Company Manitowoc. Wis. Northwestern Asbestos and Cork Insulation Co. Memphis. Tenn..................................Grant Brothers. Inc. New Orleans, La________ ______ ___________ H. T. Steffee Portland, Oregon____________________ Asbestos SupplyCompany Providence, R. I......... .Rhode Island Covering Company San Antonio, Tek..General Supply Company. Inc. San Francisco, Calif.Van Fleet-Freear Company Seattle, Wash_______________________ Asbestos SupplyCompany South Bend, Ind_____ -Asbestos A Asphalt Products Co. Spokane, Wash______ _____ AsbestosSupplyCompany Springfield, Mass._________ Johnson Asbestos Company Springfield, Mo____ .Southwestern Insulation Company Tacoma, Wabh. . ___ _________ Asbestos Supply Company Terre Haute, Ind_______ _____The Hartmann Company Tulsa, Okla________ Kelley Asbestos Products Company Wichita, Kans.... _.........--Xudeman Insulations Company For detailed technical information, samples, and descriptive literature, ask any office or representative. Complete specifications appear in each of Sweet's Catalog files. PRODUCTS--Armstrong's Corkboard, Qjrk Covering, Vibracork, Corkoustic, Temlok, Temcoustic, Insulation Sundries. Corkboard Insulating Efficiency The thermal conductivity of Armstrong's Corkboard, depending on the density, is 0.27 to 0.29 Btu per hour, per degree tem perature, per inch thickness at 90 F mean temperature (U.S. Bureau of Standards). The value of adeouate and efficient insu lation is covered in (Chapter 5) of this book and the tables on pages 100 to 112 indicate the savings which can be effected by using 1H in. or 2 in. of. corkboard in standard wail and roof construction. For air conditioning work use 1 in., 1H in., or 2 in. corkboard insulation on ducts, fans, dehumidifiers, and similar equipment. Erect corkboard in hot asphalt and tie with wires or bands 9 in. on centers or erect with Armstrong's Cements, using ties as above. Sizes and Thicknesses Armstrong's Corkboard is furnished in rigid boards 12 in.' x 36 in., 18 in. x 36 in., 24 in. x 36 in., and 36 in. x 36 in., in several thicknesses: 1 in., 1% in., 2 in., 3 in., 4 in., and 6 in. Cork Covering Armstrong's Cork Covering is made of pure cork in sizes to fit all standard pipe sizes. The inside surfaces of each piece are machined to assure an accurate fit, free from moisture-catching air pockets. ' Cork covering is'rigid and will not sag. Thick nesses are: Ice Water (1.20 in. to 1.93 in.); Brine (1.70 in. to 3.00 in.); and Special Thick Brine (2.63 in. to 4.00 in.). Armstrong's-Fitting Covers are rigid and are designed to fit accurately all types of standard ammonia and extra heavy fittings, screwed, flanged, and welded. Vibracork Armstrong's Vibracork, made in three densities, is ideal for the elimination of noise and vibration transmission and is of primary importance in air conditioning work. It does not take a set, is not affected by atmospheric moisture, and will not deteriorate under usual service. For aid .in the solution of any technical problems involving insulation, isolation, or acoustical treatment, and for literature and prices, get in touch with an Armstrong district office or distributor or the Arm strong Cork Company, Building Materials Division, Lancaster, Pa. 1025 Insulation The Barrett Company 40 Rector Street, New York, N. Y. 2800 So. Sacramento Ave., Chicago, 111. Fairfield P. O., Birmingham, Ala. DESCRIPTION AND INSULATING VALUE TYPES FOR NEW AND OLD CONSTRUCTION Barrett Rock Wool, a fibrous, free from impurities and extrane fluffy, wool-like mineral material ous material. --over 90 per cent dead air cells--- Barrett VB* Batts havea special is an excellent insulation against water-repellent, vapor-resistant cold, heat and sound. It effectively paper backing with a 1J^ in. flap reduces heat losses when applied in walls on all edges for lapping adjacent batts and and under roofs. As much as 30 per cent-- framingto form a vapor seal. Batts apply sometimes even more--fuel savings are either vertically or horizontally between had. In summer homes are as much as 15 standard 16 in. or 24 in. framing. Full, degrees cooler than out of doors. Reliable thick or semi thick, sizes 15 in. x23 in. and laboratory tests give Barrett Rock Wool a , 15 in. x 48 in.; also Demi (Junior) Batts-- thermal conductivity rating of under 0.27 without paper backing, full thick, 9 in. x Btu at 72 F. 15 in. Barrett Rock Wool will not burn. In Type GS, loose granular form, is blown wall and roof spaces which otherwise would pneumatically into stud, rafter and joist serve as flues, it reduces building fire haz framing spaces of walls, roofs, ceilings and ards. The National Bureau of Standards floors without any building alterations. fire rating for wood frame bearing and non Wall insulation thickness is stud depth-- bearing walls is 1 hr. or 1 % hrs respectively approximately 3% in. density is under when covered with wood or metal lath and 10 lbs per cubic ft. This work is only done gypsum plaster and filled with batt type by our Authorized Home Insulation Ap wool. New York City, Board of Standards plicators. and Appeals, has approved Barrett Rock Complete specifications and technical data Wool for fire-retarding construction. on all types of Barrett Rock Wool Insulation It is a non-conductor of electricity--ap will he furnished on request. proved by Underwriters Laboratories, Inc. for use around electric wiring. Barrett Rock Wool will not deteriorate with age. It is rot-proof, stable, light weight, will not settle, and is vermin resistant. It is extremely water-repellent material in a saturated atmosphere for many hours gained under 0.2 per cent in weight due to moisture absorption. It is INDUSTRIAL. INSULATION A complete line of Rock Wool insulating products, including Barrett Blankets, Bar rett No. 1200 Plastic Insulation, Barrett Pipe Insulation, Barrett Stove Rolls and Barrett Cold Storage Insulation is avail able for all types of industrial installations. Complete information on request. uniformly high in quality---clean, odorless, ^Registered U. S. Pat. Off- Barrett VB* Batts are imprinted "Barren." Paper Barrett Rock Wool easily blown through hose into firmly anchored to wool, extends beyond all edges . wall and roof spaces. Inside of building not dis- nf bait for effective vapor barrier--easy application. lurbect during application, no opening marks left. 1020 Insulation The Philip Carey Company Manufacturers of Heat Insulation and Asbestos Products ' Lackland Atlanta. Ga. Baltimore. Mo. . Boston, Mass. Buffalo. N. Y. Charlotte. N-C. Chattanooga. Tens. Chicago. III. Cincinnati. Ohio Cleveland. Ohio Columbus. Ohio Dallas. Tex. Davton. Ohio Detroit. Mich. Cincinnati, Ohio Offices Indianapolis, Ind. Kansas City. Mo. Los Angeles. Cal. Louisville, Ky. Minneapolis, Minn. Mew York, N.Y. Norfolk, Va. Philadelphia. Pa. Pittsburgh, Pa. St. Louis, Mo. Seattle, Wash. Wheeling, W. Va. Standard W deg Elboiv assembly. Left: Core opened to show duct vanes. Right: The completed fitting. Careyduct is a new prefabricated insulated duct built entirely of as bestos. The double layer construc tion consists of an inner core of hard, rigid asbestos, and the outer jacket is made of multiple layers of a fine corrugated asbestos structure. The _ combination results in great strength, is an excellent insulator, and has a definite sound deadening effect. Careyduct fittings are made from standard sections of duct, and may be made in the field with compara tive ease by men without special training. A simple mitre cut plus a few standard accessories make a complete fitting thus keeping costs at a minimum. Prefabricated fit tings may be ordered from the fac tory if desired. The telescopic assembly method practically eliminates leaks that are commonly found in other construc tion. The standard sizes of Careyduct are designed so that a combination of smaller,sizes will exactly nest in a larger size. All tees and take-offs are a combination of ells and straight duct: Standard l in. and Yi in. thick Careyduct sections with core extended. Grilles and dampers are installed according to the accepted standard practice. Careyduct gives high in sulating value. It materially reduces the transmission of extraneous and equipment noises. Careyduct costs decidedly less than properly insu lated metal duct and compares very favorably with sheet metal duct of standard quality. h'or more detailed information write for Catalog and Erection Manual. 1027 Insulalion Ttte Reldtex Rorpdration -- 919 N. Michigan Ave., Chicago, Illinois Mills: MARRERO. LA.. METUCHEN. N. J.. PORT CLINTON. O.. MARIETTA. O. Boston. Mass. Minneapolis. Minn. Philadelphia, Pa. Denver, Colo. ':- New York, N. Y. ' ; Cleveland. Ohio Los Angeles. Calif. ^ St. Louis. Mo. AND LONDON, ENGLAND Oeilq)TEX ' BRAND INSULATING CANE BOARD Seattle, Wash. Atlanta, Ga. Sydney. Australia Paris, France London, England Buenos Aires, Argentina Durban. South Africa Builds Protects - Insulates - Decorates Subdues Noise Building Board Lath Vapor-seal Sheathing Finish Plank Vapor-seal Lath Tile Board Roof Insulation Traffic Top Celotex Acoustical Products Thermax Structural Insulation Ornaments-Mouldings Key Joint Units Celotex Rock Wool Products Celotex Products also include Roofing . .. Gypsum ... Hard Boards . .. Flexcell Expansion Joint. . . Pottsco Lightweight Concrete Aggregate. Celotex Cane Fibre Insulation In the manufacture of Celotex cane fibre insulating products, long tough fibres of bagasse (cane) are properly refined, felted and interwoven to produce large boards of maximum strength and efficiency. All Celotex cane fibre insulating, products are dry rot and termite proofed by the exclusive patented Ferox Process--an integral treatment that is permanent. The thermal conductivity of Celotex cane fibre insulation is 0.33 per hour per square foot per degree Fahrenheit pier inch thickness (based on a mean temperature of 70 F.) The Celotex Corporation Engineering and Research staff is available for all types of insulation investigations. Address problems to the Chicago office. Celotex Vapor-seal Insulating Sheathing and Lath A rigid, strong, insulating sheathing for use on outside walls under any type of exterior. AH sur faces and edges moisture-proofed with a coating of special asphalt . . . one side additionally coated with an aluminum paint as an added vapor barrier. All coatings are on the surfaces--no impregnation--thus maintaining full insulating efficiency . . . the alumi num side is applied facing studs. . . Backed by the Celotex Written Life-of-Building Guarantee. Same thickness as wood sheathing it replaces--25/32 in. thick, 4 ft wide; 7, 8, 8Y, 9, 9M* 10, and 12 ft long applied parallel to studs. The 2 ft x 8 ft units are center matched and applied across the studs. In combination with Vapor-seal Sheathing, Celo tex Vapor-seal Insulating Lath, with its vapor seal on the warm side of the wall, protects against harm- . ful moisture condensation within the walls. Provides a natural bond for plaster . . - a continuous surface eliminates lath marks and reduces cracking . . beveled edges (patented) reinforce plaster. Sizes: 18 in. x 48 in.; Y in. and 1 in. thicknesses. Regular Celotex Insulating Lath also available in Yz in., % in., and 1 in. thickness and same size. Celotex Building Board Suitable for general use where an insulating board is desired. Can be beveled, paneled, grooved or painted to provide attractive interior walls and ceilings that insulate. Tapes try-like texture on one side, opposite side either smooth sanded, neutral tan or ivory finish. Yz in. and 1 in. thick. Sizes: 4 ft wide and 4, 5, 6, 7, 8, 9, 9Y> 10, and 12 ft long. Backed by Celotex Life-of-Building Guarantee. 1028 The Celotex Corporation Insulation Celotex Ro/bf Insulation Selected to insulate wood, concrete, steel, unit tile or poured gypsum roof decks. Also /Aised to prevent ceiling condensation and conserve fuel; and to prevent excessive exf\pansicn and contraction of concrete roof decks. Makes possible a reduction in the size **`of heating plants. One size only: 22 in. x 47 in. Full Y in. thick. Also furnished laminated in thicknesses of 1, l Yz* and 2 in., with square or off-set edges. Celotex Insulating Tile, Finish Plank and Key Joint Units Tile Board and Finish Plank--In various attractive colors ... for new walls or finish over existing plaster. Type Double-A joint is standard on tile and plank and permits alternated surfaces if desired. Type Double-A joint Y in. thick carried in stock, and 1 in. thick available on special order. Tile sizes range from 12 in. x 12 in. to 24 in. x48 in. Plank sizes: Applying Celotex Roof Insulation 6 in. to 16 in. wide; 8 ft to 12 ft long. Beveled butt or shiplapped edges. Key Joint Units--Interior finish material with all edges molded and grooved for furnished splines. These splines form a new decorative joint. Shadows in joints hide nailing. Cutting necessary at boundaries only. The units are of related sizes, permitting innumerable designs. Sizes: 16 in. x 16 in., 4 ft, and 8 ft; 4 ft x 4 ft, and 8 ft. Thick ness: % in. Ivory finish. Celotex Rock Wool Products Fitted snugly to framing members of walls, top-floor ceilings, or under the roof, Celotex Rock Wool Batts provide permanent, efficient protection against heat losses in winter, against the penetration of heat in summer. Incombustible, waterproofed, vermin proof, enduring with a thermal conductivity of 0.27. Batts are 15 in. x 23 in. to fit either 16 in. o.c. or 24 in. o.c. studding . . . with or without paper backing. Celotex Rock Wool also available loose or granulated. Thermax Structural Insulating Slab A fire-resisting insulating slab suitable for solid or hollow partitions, furring, suspended ceilings and load-bearing roof decks. Also as non-structural roof insulation or plaster base sheathing. Thermal conductivity is 0.458 Btu per hour, per square foot, per degree Fahrenheit, per inch thickness (Armour Insti tute). An excellent plaster base .. . when left exposed provides sound absorption plus insu -i, >y -* .. . . i lation. It is manufactured of shredded wood fibres bound with fire-resisting mineral binder. Sizes: 1 in., 2 in., and 3 in., thicknesses in slabs 20 in. x 32, 48, 64, 72 and 96, in. long. Special lengths up to 9 ft. Applying Thermax Structural Insulation Celotex Acoustical Products To serve the ever-widening field of Acous tics, The Celotex Corporation, now markets five sound absorbing products; each designed to meet architects' and engineers' specifica tions, not only for sound absorption, but for decoration as well. They are Acousti-Celotex, a patented perforated cane fibre tile; Absorbex, a wood fibre tile; Calicel and Calistone, a stone-like sound absorbing material; Muffletone, a cast gypsum tile; and Q-T Ductliner, used for ducts. 1029 Insulation Ehret Magnesia Manufacturing Go. Valley Forge, Pa. ^ A FULL RANGE OF INSULATIONS FOR HEATING AND VENTILATING The Ehret Company furnishes a broad : range of thermal insulations for practically every industrial and architectural require ment. For full details of Ehret products, see the Ehret Insulation Manual. Ehret's 85 Per Cent Magnesia Known for nearly half a century in the industrial field, Ehret's 85 per cent Mag nesia Pipe Coverings and Blocks are efficient, economical and they last indefi nitely. Pipe coverings are available in a full range of sizes and thicloiesses, and blocks can be furnished in thicknesses up to 4 in. An ideal material for use on heated pipes or surfaces whose tempera tures do not exceed 600 F. Ehret's Enduro For temperatures between 600 F and 2000 F, Ehret's Enduro is admirably suited. Frequently used in combination with Ehret's 85 per cent Magnesia for high temperature work. Available , in pipe coverings and blocks in a full range of sizes and thicknesses. Since Ehret's Enduro is made from a base of pre-calcined diatomaceous earth, it can like Ehret's 85 per cent Magnesia*,~~be--depended upon to last indefinitely. Durant Insulated Pipe The illustrations and description on the opposite page should be of especial interest . to those who specify or install insulated pipe lines in underground or weather- exposed locations. 1 Ehret's Hcat-Scnl Wool Building Insulations Other Ehret Products Included in the line of Ehret insulations are products such as Air Cell Pipe Cover ings, Anti-sweat and Frostproof coverings, Asbestos paper, Standard Hair Felt for cold piping and equipment, Cork Pipe Coverings and Blocks, finishing and insu lating cements, packings and many other insulating and allied products. 1030 Ehret Magnesia Manufacturing Co. \ Insulation EHRET'S DURANT INSULATED PIPE . . . for Underground and Outdoor Service This unique system of pipe line protection consists of pipe that is insulated, sealed and protected at ourfactory, and shipped to the job ready for installation. Pipe lengths can be joined with screwed, flanged or welded fittings, and the system provides protection for expansion bends, joints, valves and similar pipeline appurte nances. - Field joints in Durant Insulated Pipe are easy to make, and once made the backfill can be begun and the trench flooded for tamping. ' ' Ehret's Durant Insulated Pipe will not crack or leak and moisture or water is permanently excluded by the thick, time- defying layer of high-melting-point asphalt that encloses all parts of the system. Write for the special Ehret D.I.P. folder--it gives full details. Some Outstanding Advantages,of Durant Insulated Pipe: - 1. Permanently waterproof. 2. Elimination of electrolysis and corro sion. 3. Requires no sub-drains as even com plete water submersion does no harm. 4. In multiple lines, individual Durant pipes can be added, removed or re placed without disturbing others. o. Minimum trenching and field work. 6. No rollers or pipe supports required 7. No breakage or waste of material during installation. 8. Tile or masonry protection not re^ quired. 9. Field costs are much lower than those of tile, tunnel and similar systems. 10. Insulation protection is absolutely dependable. 1031 Insulation The Eagle-Picher Lead Company General offices: Temple Bar Building, Cincinnati, Ohio offices tnAii Large cities EAGLE B3 EAGLE HOME INSULATION Eagle insulation for homes is a fluffy, woolly material made from silicious miner al. In both granulated form for pneumatic application and in batt form, it is extreme ly lightweight, non-corrosive, fireproof. According to U. S. Bureau of Standards tests, one inch of Eagle Insulation has a thermal conductivity rating of only 0.27 Btu at 103 F. (Applied thickness of 3% inches gives a much lower conductivity). Fuel Savings Up to 40 Per Cent Eagle Insulation literally "seals" furnace heat inside the home. Records show that fuel savings run up to 40 per cent of the season's total. In summer, Eagle Insula tion keeps homes up to 15 deg cooler than outdoor temperatures. Reduces Fire Hazard Unlike many insulating materials which are described as "fire-safe" or "fire-resis tant", Eagle Insu lation is fireproof to 1200 F. It will not burn. Fire haz ard is greatly re duced. Hollow spaces in walls, which ordinarily act as flues once a fire starts, are com pletely filled with a material that even a blow torch can not ignite. Eagle Insulating Wool easily blown into spaces between wall studdings The Bureau of Buildings of the City of New York has iven full approval to use of Eagle Insulation where fire-retarding is required under the. Building Code and the Multiple Dwelling Law. Also approved by Underwriters* Laboratories, Inc. as being a non-conductor of electricity. Water Repellent Samples of Eagle Insulation exposed to completely saturated atmosphere for 100 hours gained less than 0.2 per cent in weight due to moisture absorption. This is important. Insulating materials which absorb water soon lose much of their in sulating efficiency. Being made of mineral wool, Eagle Insulation contains no vegetable matter to attract insects or pests. It is rotproof --will not deteriorate. It passes the most severe settling tests. Type H-l. Applied Pneumatically In granulated form, Eagle Insulation is blown- into hollow spaces between wall studdings and between joists in the attic floor by a special pneumatic process. No building alterations are necessary, whether the structure is of frame, brick veneer or stucco construction. Work is done by skilled authorized contractors. Type H-3. Batts for New Construction Eagle Insulat ing Batts are rec tangular pads in suitable sizes to*fi snugly between studding and joists. Equipped with a water proofed paper back. Batts are easily cut to fit Eagle wall-thick baits quickly installed in new construction irregular spaces when necessary. Data and Specifications For complete specifications and tech nical data on Eagle Home Insulation, see Sweet's Architectural Catalog. EAGLE INDUSTRIAL INSULATION The Eagle-Picher Lead Company manu are fabricated for temperatures up to 1700 factures a varied line of insulating products F. All standard Sizes. Easy to cut and fit. effective for a full range of temperatures. Other products are pipe insulation, roll Eagle Super "66" Plastic Insulation and felted wools for air conditioning ap provides remarkable heat-saving efficiency purtenances and other industrial uses, for temperatures as high as 1800 F. Trowels insulating cements and loose wool. easily on all large or irregular surfaces. 100 For specifications and technical data on lb give 50-55 sq ft 1 in. thick dry coverage. Eagle Industrial Insulation, see Sweet's Eagle Supertemp Insulation Blocks Engineering or Power Plant Catalog. 1032 Insulation General Insulating & Mfg. Company Engineering Offices and Main Plant: rjj ^ Alexandria. Indiana Executive Offices: St. Louis, Missouri Branch Plants: Dover. N. J. Dubuque. Iowa ROCK WOOL C insulation Cimco Sealal Bats, furnished with waterproof paper back ing. fit between standard stud dings and joists. Gimco Sealal Rock Wool Bats--Gimco Rock Wool Bats are made from long, tough rock wool fibres annealed and treated specially by the patented Gimco process. Installed 3% in. thick Gimco's conductivity is only 0.067 Btu per hour per sq ft for that thickness. Gimco provides full "wall-thick" protection . . . keeps inside temperatures as much as 15 deg cooler in summer and pays for itself out of winter fuel savings. Gimco is as fireproof as the rock itself, resists moisture, and will not decay, pack down or dust out. Gimco is as permanent as the house, and offers no attraction to vermin or termites. Gimco Bats are Self-Supporting,:--Gimco bats need only to be pushed between studdings or joists. Their own natural resiliency holds them permanently in place without additional support. Application costs are thus cut to a minimum. Gimco Insulation for Present Homes--Gimco. in granu lated form can easily be blown into empty wall and ceiling spaces. It makes a permanent "wall-thick" insulation, ana can be installed in any home, regardless of age, size or type of construction. For complete details, write Tor new book on home insulation. Specifications--Gimco Sealal Bats are furnished with waterproofed paper backing. They are made in three sizes: (1) 15 x 18 in. x wall thick; (2) 15 x 23 in. x wall thick; (3) 15 x 48 in. x wall thick. Ten small bats insulate approximately 20 sq ft of wall or ceiling area; 10 medium size bats insulate approximately 25}$ sq ft; 10 large tots insulate approximately 55 sq ft. . Present homes are easily and uickly insulated by blowing gHmco Rock Wool in empty wall and ceiling spaces. In sures a thick, protective blanket of uniform density. GIMCO ROCK WOOL PRODUCTS FOR INDUSTRY Flexfelt Blankets--Efficient and adaptable rock wool insulation for boilers, heaters, furnace breachings, hot tanks and other industrial equipment. Standard sizes: 2 ft x 4 ft and 2 ft x 8 ft. Special sizes are also made to order or as planned by our engineers from pur chasers' equipment drawings. Gimco Flexfelt Pipe Coverings--Flexfelt coverings are suited for every type of pipe insulation . . . hot water, steam process, cold water and refrigerant lines. They are made in a variety of sizes and styles, each individually designed to do an efficient insulating job. Gimco No. 330 Insulating Cement can be easily and quickly applied to any surface. It dries quickly with little shrinkage and has a smooth, hard surface. Cost per square foot coverage is unusually low. Free Construction and Engineering Service--Gimco engineers, backed by years of research in our own laboratories, render prompt and efficient service in helping you solve insulation problems. Quotations and suggestions on any job (temperatures up to 1500 F) will be gladly given. 1033 Insulation The Hinde & Dauch Paper Co. Manufacturers of Air Cell Insulation General Offices: Sandusky, Ohio Factories In: Baltimore, Boston, Buffalo, Chicago. Cleveland. Detroit, Gloucester City, N. J., Hoboken, N. J., Kansas City, Lenoir, N. C., Muncie, Ind., Richmond, Sandusky, Ohio, St. Louis. "IDEAL"--A HEAT BARRIER Ideal Air Cell Insulation placed between studs, joists and rafters with circulating air over both its surfaces, serves as a barrier to the escape of heat, but permits the continued movement of moisture. Ideal Air Cell Insulation, a purely mechanical structure comprising 5 percent solid material and 95 per cent confined non-circulating air, is manufactured from chemically pure Kraft paper--an organic material of high absorbent properties. The natural movement of moisture vapor (carried by air alone) is from a point of high vapor pressure to a point of lower vapor pressure, or practically speaking, from a warm to a colder area. 1034 Hinde & Dauch Paper Co. Insulation - HIGHLY ABSORBENT . Because of the high absorbent property 4>'of the paper used, all moisture deposited on "the inner or warmer surface is transferred ' through its structure to the outer or colder surface, while the confined non-circulating air within the structure proper retards the escape of heat. dimension. Odd or irregular shapes are easily cut to size with knife or carpenter's saw. Installing strips 3^ inch wide with % inch channels in center clamp the insu lation on both edges, insuring proper spacing, and are placed between studs, joists or rafters as a unit. Once nailed in place, the installation is permanent. Ideal Air Cell Insulation standard specifications are I in. in thickness, sheets 8 ft long and widths to con form with regular building practices. When ordering, state on what centers the studs, joists or rafters are set, and the lineal feet of each width required. Shipped in wrapped bundles of 6 sheets each. Shipping weight for Insulation 240 lb per thousand square feet; Installing Strips 100 lb per thousand lineal feet. The function of insulation is to stop radiation and convection, with out materially increasing conduc tion, due to the presence of solid material. Ideal Air. Cell Insulation has only 5 per cent of sojid material per cubic measure, while there are 42 sq ft of exposed surface per 1 sq ft of 1 in. thickness for evaporative drying, which precludes the possibility of a moisture build up within the material. EASY TO INSTALL Ideal Air Cell Insulation is easy to install--materials are rigid in the width dimension and flexible in the length RETARDS HEAT Ideal Air Cell Insulation overcomes radiation by the simple method of interspacing a number of thin par titions in the heat path as barriers, thus effectively retarding the pas sage of heat rays. . Ideal Air Cell Insulation stops convection by the proper spacing of the barrier sheets. It has been successfully demonstrated that the spacing of the sheets, as found in Ideal Air Cell Insulation, practically stops all movement of air within the insulation itself. REDUCES CONVECTION Ideal Air Cell Insulation reduces conduction--by volume 95 per cent confined non-circulating air and 5 per cent solid material, the lowest percentage of solids by volume of any commercial insulating material known. At 75 F mean temperature, passes only 0.26 Btu per square foot, per inch thickness, per degree F, per hour --truly a wonderful heat blocking record. DEADENS SOUND Ideal Air Cell Insulation possesses excel lent sound deadening properties and is often used in this capacity. For descriptive literature and sam ples, write to general office at San dusky Ohio. . 1035 Insulation INSULITE General Offices 1100 Builders Exchange, Minneapolis, Minnesota New York--101 Park Avenue Chicago--205 W. Wacker Drive Sales Solicitors Offices San Francisco--475 Brannan St. St. Louis--1206 S. Vandeventer TWENTY-SIX YEARS PROVEN DURABILITY For 26 years engineers and architects have specified Insulite materials for struc tural uses, interior finish, duct lining, and for other thermal insulation and sound control work. Insulite. materials have proved themselves practical through their performance on the job. You are invited to consult any Insulite office for cooperation in problems concern ing insulation, acoustics, and sound control. INTERIOR FINISH MATERIALS Ins-Lite Building Board--A wood fiber board with the light color of natural wood--burlap and linen surfaces. Thermal conductivity: 0.33 Btu/hr/sq ft/in./F based on a density of 16 lb/cu ft. Fur nished in thicknesses of % and 1 inch and sizes of 4 x 4 ft to 4 x 12 ft. Also available in 6 ft x 8 ft, 6 ft x 12 ft and 8 ft x 12 ft sizes for ^ in- and % in. thicknesses. Graylite Building Board-- An integ rally treated asphalt containing wood fiber board of grayish brown color--burlap and linen surfaces. Thermal conductivity 0.35 Btu per inch thickness. Furnished in same thicknesses and sizes as Ins-Lite Building Board. Smoothcote Interior Board--Coated Insulating Board with smooth, hard sur face one side, having 67 per cent light re flection. Furnished in ^ inch thickness only and in sizes of 4 x 4 ft to 4 x 12 ft. cote and Satincote Tile Board also avail able in above sizes in ^ inch thickness only. Plank--Available in Ins-Lite, Graylite, Smoothcote and Satincote, Plank has the interlocking V-W joint and is beveled and beaded both long edges. InsLite and Graylite Plank furnished in % and 1 inch thicknesses and widths of 6 to 16 inches and lengths of 8 to 12 ft. Smooth cote and Satincote Plank furnished in % inch thickness only and in above sizes. Acoustilite--A high efficiency acousti cal material for sound control. Coefficient of sound absorption, 0.79 at 512 cycles. Factory painted in buff and in white. Thickness, % in.; sizes, 12x12 in. to 16x32 in. Fiberlite--An efficient sound absorp tive and decorative material. Factory painted in buff and in white. Coefficient of sound absorption 0.58 at 512 cycles. Thickness, H in.; sizes, 12x12 in. to 16x32 in Satincote Interior Board--Factory finished Insulating Board in colors buff, gray, coral and green. Requires no further decoration. Highly resistant to abrasion and easily washable. In ^ inch thickness and in sizes of 4 x 4 ft to 4 x 12 ft. Tile Board--Available in Ins-Lite, Graylite, Smoothcote, and Satincote. All Tile Board furnished with a V-W inter locking joint or a beveled and butt (B-B) joint all edges. Ins-Lite and Graylite Tile Board avail able in or 1 inch thicknesses and sizes of 12 x 12 inches to 24 x 48 inches. Smooth Insulite for Interior Walls and Ceilings STRUCTURAL MATERIALS Lok-Joint Lath--An insulating plaster base, fabricated from Ins-Lite and from Graylite. Patented "lok" firmly locks Bildrite Sheathing is an asphalt-con taining wood fiber board manufactured under an exclusive process which provides the sheets between supporting members. Thicknesses: Mand 1 in. Size: 18x48 in. Sealed Lok-Joint Lath--An insulating increased strength and moisture resistance. It is 2%2 >n. thick and has a distinctive gray-brown color. Thermal conductivity: plaster base-of Graylite, Sealed on stud space side with an effective vapor barrier. Has patented "Lok" on long edges. Fur nished in same thicknesses and size as 0.36 Btu per inch thickness. Each sheet is marked to indicate proper nail spacing. Available in sizes 4 x 8 ft up to 4 x 12 ft. Used as a structural sheathing board and Ins-Lite and Graylite Lok-Joint Lath. as a roof boarding. 1036 Insulite_________________________________________ Insulation INSULITE WALL OF PROTECTION* Coefficients of Transmission (U) of various types of frame construction. Granulated Fill, for pouring into place; Batts, thicknesses 2 and 3% in.; Paper backed Batts, thicknesses 2 in. and wallthick; Pads, wall-thick; and Pre-packed, roughly 2 in. thick. The Batts are 15 x 23 in. and 15 x 48 in. in size, and the Paper-backed Batt is lined . on one side with a vapor proofed kraft paper, flanged all four edges. Pads and Pre-packed forms are 15 x 9 in. in size. HardBoard Products HardBoard materials are tough, durable, grainless, pressed wood fiber boards with a hard, smooth surface. Available in a range of densities from 37 to 68 lb/cu ft. Thick nesses are from Yo to Yu in. and sizes of 4 x 2 ft to 4 x 12 ft. Industrial Insulation The above values are typical of results which can be obtained by utilizing Insulite materials in frame construction. For further (U) values refer to Chapter 5. pages 104 and 105. Ins-Lite Roof Insulation Fabricated from wood fiber board. Size: 22 x 47 in. with either offset or square edges. Thicknesses: I, 1^, and 2 in. Thermal conductivity: 0.32 Btu per inch thickness. Used as insulation on all types of roof decks under built-up roofing. Graylite Roof Insulation An integrally treated asphalt containing wood fiber board of gray brown color. The asphalt treatment provides not only added strength and moisture resistance, but also a better natural bond with the bitumen used on the job. Available in same thick nesses, size, and edge treatment as Ins-Lite Roof Insulation. Thermal conductivity: 0.35 Btu per inch thickness. Industrial Insulation is a wood fiber board for use in all types of manufacturing industries producing items such as refriger ators, coolers, showcases, brooders, parti tions and cabinets. It can be cut-to-size and fabricated to customer's specifications. Three types of industrial board are available. Lowdensite Industrial Board--A 10 to 14 lb density board with an average tensile strength of 100 lb/sq in. and an average conductivity of 0.30 Btu/inch thickness. Ins-Lite Industrial Board--A 14 to 18 lb density board with an average tensile strength of 250 lb/sq in and an average conductivity of 0.33 Btu/inch thickness. Graylite Industrial Board--Differs from two above products in that it has an integral asphalt treatment which provides increased strength and moisture resistance as well as minimum thickness and linear expansion. A 16 to 20 lb density board with an average tensile strength of 350 lb/sq in. and an average conductivity of 0.35 Btu/inch thickness. Ins-Lite Cold Storage .Insulation Fabricated from special low density wood fiber board, 12 lb per cu ft. Average thermal conductivity is 0.30 Btu per inch thickness. Available in eleven standard sizes of 12 x 18 in. up to 24 x 48 in. Thick nesses: 1, IH, 2, 3, and 4 in. For use as insulation on walls, floors, and ceilings of ice houses, cooler rooms, storage plants, breweries, and wherever low temperature control is necessary. Insulite Fiberock A rock wool product available in six forms: Loose Fill, for hand packing; Applying Insulite Roof Insulation 1037 Insulation 10807 Lyndon at Meyers Road SULALION DU STR I ES CORPORATED DETROIT ROCK WOOL INSULATION PRODUCTS Detroit Michigan BUILDING INSULATION PRODUCTS Loose Rock Wool (paper bags) Granulated Rock Wool (paper bags) Rock Wool in Rolls (any length or thickness) Rock Wool Batts (cartons) (with or without paper backs) Rock Wool Batts (bags) (without paper backs) Insulation Industries Incorporated owns and operates one of the most modern, up-to-date Rock Wool plants. Rock Wool is manufactured by a patented, precision process that produces a superior grade of Rock Wool. It is light in weight, has long, silky and resilient fibers. It is clean and free from foreign particles. Rock Wool is indestructible and will last as long as the building itself. It is fire-proof, vermin and rodent-proof and is resistent to moisture. BUILDING INSULATION Rock Wool is suitable for all types of building insulation requirements. It can be applied in the granulated form by the pneumatic method to existing homes or buildings. For new construction or for unfinished attic or wall spaces, Batts are furnished either 15x23 in. or 15x 48 in. and 2 or 4 in. thick and with or without paper backs, packed in cartons. Long fiber Rock Wool in loose form is available packed in 35-lb paper bags. RESULTS Results obtained in all types of build ings, both old and new, show substantial INDUSTRIAL INSULATION PRODUCTS For Stoves and Ranges Water Heaters ' Industrial Ovens Bakery Ovens Large Diameter Pipes Boiler Settings, etc. . . savings in fuel consumption with elimi nation of drafts and variation of tempera tures between rooms and floors. . BLANKETS Long fibered, especially treated Rock Wool, felted and secured between metal fabrics of different types. These blankets are made in standard sizes 24 in. x 96 in. and 24 in. x 48 in. and special sizes as re quired and any thickness from 1 in. to 8 in. Applicable to flat or curved surfaces. INSULATING BLOCK Rock Wool fabricated into sheet or board form from H in. to 4 in. thick, 24 in. x 36 in. or special sizes, as required. This block is widely used for insulating boilers, ducts, tanks, stills, etc., and for domestic furnaces, boilers, ranges and hotwater tanks. INSULATING CEMENT For finishing block and blanket insu lation. For temperature conditions from 100 to 2000. Is very plastic and is quickly and easily applied. SPECIFICATIONS Write for complete information and details on Insulation Industries products. Rolled wool Balls in bags any thickness 8" x 15" x 4" Granulated Wool Long Fiber Loose Wool 1038 Paper Backed Batts Blanket--Paper both sides Insulation International Fibre Board Limited ' Sales Offices ^OTTAWA, MONTREAL, TORONTO. Administrative Offices and Mills: GATINEAU, QUEBEC. London Office: THE TenTest FIBRE BOARD CO.. Limited 75 Crescent West, Hadley Wood, Barnet, Hertsfordshire, England. TE T: WALL BOARD TEN/TEST is a manufactured lumber made from spruce fibres, solidly pressed under hydraulic pressure into a strong, homogeneous board. The fibres are chemically treated and water-proofed during process of manufacture, until the insulation is non-hygroscopic, free from capillary attraction and moisture-resisting in service commensurate with the maximum degree of insulation obtainable. TEN/TEST Products TEN/TEST Insulating Building Board. Standard insulation for use as exterior sheathing, interior finish; between walls and under floors for sound deadening. Standard Industrial Insulation for refrig eration and the prevention of condensa tion. Manufactured in convenient sizes: 4 ft wide and up to 17 ft long, H in. to. 1 in. thick or laminated to any desired thickness. TEN/TEST Notch Board Plaster. Base. Insulating plaster base haying tongue and groove interlocking joints. Provides an effective bond with plaster without use of metal lath at joints. Sizes: 16 in. wide; 32 in. and 47H in. long. Thicknesses from in. to 1 in. or laminated to any desired thickness. TEN/TEST Roof Board. An effective roof insulation. Manufactured in two sizes: 1 x 4 ft and 2 x 4 ft. Thicknesses from H in. to 1 in. or laminated to any desired thickness. TEN/TEST Ashlar Block. For interior decoration and acoustical correction. Can be supplied in a variety of designs and sizes to harmonize with any decorative treatment. . TEN/TEST Acoustical Tile and Panels with sound absorption coefficients ranging up to 0.53 at 512. Specially de signed for churches, schools, auditoriums, theatres, etc. TEN/TEST Moulded and Shiplap Edge Wall Panels. Conceals joints and provides excellent decorative treatment. Featured in widths of 11 in. to 47M in , lengths up to 12 ft. TEN/TEST Mouldings. An effective trim and finish for joints, corners, etc. Available in widths of % in. to 10 in. and lengths up to 12 ft. HYDRO/TEST. Water proof, insula ting building board, designed particularly for low temperature requirements. Official Tests Conductivity. TEN/TEST has a con ductivity of 0.33 Btu per hour per square foot per degree Fahrenheit per 1 in. thick. Authority: Professor E. A. Allcut, M. Sc. M. I. Mech. E. Mem, A.S.M.E. Professor of Applied Mechanics, University of Toronto. Tests performed by Hot-Plate method. Mean temperature 47.8 deg. Plaster Bonding Strength 2163 lb per sq ft. Brown and scratch plaster coats were applied to standard He in. board, and the pull registered in an Olsen Testing Machine. Authority: Columbia University Testing Laboratories, New York. Moisture Resisting. TEN/TEST, after complete immersion in water for 24 hours, registered 37.5 per cent increase in weight. Tensile Strength 228 lb per sq in. Tests, made on H6 in. board cut to strips 1 in. wide and tested in a Riehle Tensile Testing Machine, the grips being 2 in. apart. 228 lb is the mean average of seven series of tests. Transverse Strength (equal deflec tion) is 28.4 lb. Test made On He in board, 6 in. wide, 18 in. long, on 12 in. centers, and load being applied to breaking point. Note.--Authority for tensile strength, transverse and moisture tests; J. T. Donald & Co., Ltd., Chemical Analysts and Engineers, Montreal, Que. 1039 Insulation Johns-Manville Executive offices: 22 East 40th Street, New York, N. Y. Offices In All Large Cities Johns-Manville Home Insulation Johns-Manville Super-Felt Home Insu lation is a light, fluffy mineral wool, highly efficient in heat-proofing practically any building, old or new. It is durable, rotproof, fire-proof and odorless, and will not corrode or settle. Full stud thickness of this material will cut fuel costs up to 30 per cent in winter, and, help keep rooms up to 15 deg cooler in hottest weather. J-M Super-Felt Home Insulation is, furnished in two forms: for new construction, in easily handled batts; for existing buildings, in loose, nodulated form to be installed pneumatically. space between studs, joists and rafters on the usual 16 in. centers. Type B Super Felt batts are backed with .waterproof, vapor-resistant paper, extending on the long sides in a 1J4 in. wide flange, by which the batt is fastened in place and which also aids in sealing the joints. This backing protects against penetration of moisture from wet plaster and also resists infiltra tion of moisture vapor from the house into the wall. Junior Super-Felt Batts are similar to Type B except that they are not paper backed and are furnished only in size 12 x 15 in. by full stud thickness. Type C Super-Felt Home Insulation is an improved form of loose wool, in pieces 8 x 15 in., without paper backing, which readily fluffs to full walk thickness when installed. Both Junior Super-Felt Batts and Type C Super-Felt can be readily installed in irregular spaces since they are easily cut or torn with the hands. Applying J-M Super-Felt Type B balls in new home For New Construction Super-Felt Types B, C and Junior Batts Super-Felt Type B Home Insulation is furnished in pre-fabricated batts of uni form density, in both full stud thickness and semi-thick, in sizes 15 x 23 in. and 15 x 48 in., designed to fill completely the For Existing Homes and Buildings Type A "Blowing Rock Wool Type A Rock Wool is blown pneu matically into the spaces between studs in outer walls and between rafters or joists in roofs or attic floors. Insulation thickness in walls corresponds to stud depth, ap proximately Zii in.; density does not exceed 10 lb per cubic foot. This type of insulation is installed only by Approved J-M Home Insulation Contractors, who are equipped with the necessary apparatus and trained crews. ' Write for Details . Complete information on all types of J-M Home Insulation will be furnished on request. ' J-M Airacoustic Sheets for lining Air-Conditioning Ducts J-M Airacoustic Sheets, for duct linings of air conditioning systems, are rigid, fire proof, highly sound-absorbent and mois ture-resistant, with a surface which will not materially increase friction losses in the duct system. Write for DS Series 275. 1040 JohnS'Manoille Insulation Johns-Manville Pipe and Boiler Insulation J-M Asbesto-Sponge Felted Pipe Insulation Recommended on all high pressure steam piping at temperatures up to 700 F where insulation may be subjected to rough usage or where maximum efficiency and durability are desired. Furnished in 3-ft sections up to 3 in. thick, for all com mercial pipe sizes. J-M Superex Combination Superex Combination Insulation (an inner layer of high temperature Superex and an outer layer of 85% Magnesia) is recommended where temperatures exceed 600 F. Superex and Magnesia are both furnished in sectional and segmental pipe covering, and in block forms. J-M Pre-Shrunk Asbcstocel Pipe Insulation J-M Pre-Shrunk Asbestocel is a radically improved insulating material for hot water or low pressure steam piping, which, since it is made of moisture-proofed asbestos paper, minimizes objectionable shrinkage. Supplied in canvas, asbestos paper or aluminum finishes. All types furnished in 3-ft sections in standard thicknesses of 2 to 8 plies, each ply approximately Y\ in. thick, for all commercial pipe sizes.* J-M 85% Magnesia Recommended as the most efficient in sulation of the molded type for tempera tures up to 600 F. Pipe insulation is furnished in sectional or segmental form' for all commercial pipe sizes,* in thick nesses up to 3 in. Blocks are 3 in. by 18 in. and 6 in. by 36 in., flat or curved, from Yt in. to 4 in. thick. Minimum thickness for curved blocks, 1)4 in. J-M Pre-Shrunk Wool Felt Pipe Insulation Due to its Dual-Service Liner--an asphalt-saturated felt--J-M Pre-Shrunk Wool Felt is equally effective and durable on either hot or cold water service piping. By the use of waterproofed felts, shrinkage troubles have been minimized. Supplied in two finishes, the regular canvas and a smooth, dull-coated alumi num. In either finish, it is furnished in 3-ft sections in thicknesses of )4 in. )4 in., 1 in.. Double Vz in., and Double )4 in., for all commercial pipe sizes.* J-M Asbestocel Sheets and Blocks Asbestocel Sheets and Blocks are used for insulating warm-air ducts, flues, heater casings and fan housings in the ventilating system. Temperature limit 300 F. Fur nished 6, 9, 12, 18 and 36 in. wide by 36 and 72 in. long, from Y in. to 4 in. thick. J-M Rock Cork Sheets and Pipe Insulation J-M Rock Cork is made of mineral wool and a moisture-proof binding ingredient molded into sheets for insulating refriger ated rooms and air conditioning ducts; and into sectional pipe insulation with an integral waterproof jacket, for all low tem perature service. It is strong, durable, and will not support vermin. Because of its unusual moisture resistance, its high insu lating efficiency is maintained in service. Furnished in sheets 18 in. by 36 in., in 1)4. 2, 3 and 4 in. thicknesses; also 18 in. by 18 in. by 1 in. thick. In lagging form, for cuiyed surfaces, supplied 18 in. long by 1/4, 2, 3 and 4 in. thick, 2 to 5 in. wide, depending on diameter. In pipe covering form, in ice water, brine and heavy brine thicknesses, for all commercial pipe sizes. Details on Request Write for complete information on any Johns-Manville insulating material. Can also be supplied in sections to fit straight runs of copper pipe or tubing with outside diameter H in. and larger. 1041 /nsulalion n\eiitit.Lef >*/aniiny lanhet .0G9t!9(LA'ukQl}9 KIMBERLY-CLARK CORPORATION ESTABLISHED 187? Building Insulation Division 8 South Michigan Avenue, Chicago, Illinois MANUFACTURERS OF STITCHED EXPANDING BLANKET INSULATION NEENAH. WISCONSIN KIMSUL* is a wood fiber product manufactured by the KIMBERLYCLARK CORPORATION, who have been making wood fiber products since 1872. KIMSUL is produced in long, contin uous flexible blankets, composed of many creped layers or plies, providing a maxi mum number of dead air cells. The finished blanket is firmly stitched, assur ing a durable, yet completely flexible blanket of high insulation efficiency, which is easy to handle and install. KIMSUL is delivered in cartons con taining sufficient KIMSUL to insulate250 sq ft in Commercial thickness; or 125 sq ft in Standard thickness; or 833^ sq ft in Double-Thick. PHYSICAL PROPERTIES 1. Thermal Efficiency--KIMSUL'S conductivity is .27 Btu hr/sq ft/F/inch (J. C. Peebles)--one of the most efficient heat "Blockaders" developed. This con ductivity is at the extremely low installed density of 1.57 lb per cu ft . . . installed density maintained by stitching. UNIQUE PROPERTIES OF EXPANSION AND STITCHING Expandability--Delivered to a job in a compressed form, each blanket of KIM SUL, when installed, is expanded to about 5 times its original length without decreasing the intended thickness or lessen ing its heat stopping ability. Speeds Work--Lowers Cost--Because KIMSUL is delivered in compressed form it is easier to handle; storage costs are reduced--and it goes up quickly. KIMSUL blankets are made in widths to fit snugly between studding and rafters--little measuring or fitting is neces sary. Using shipping carton as a dispensing container, the end of KIMSUL blanket is nailed on at the top--blanket expanded and attached at bottom--then cut off. That is all there is to it. Stitching Controls Efficiency and Permanence--Each blanket of KIMSUL, before being compressed, is stitched its entire length with rows of twine approxi mately 20 times stronger than necessary to support its entire weight. This prevents KIMSUL from being expanded beyond its most efficient density. It also prevents sagging and helps to hold KIMSUL in place permanently. . *Reg. U. S. & Can. Pat. Off. 2. Flexibility--Flexible as a blanket, KIMSUL fits snugly. It can be tucked behind wire and piping, moulded to the shape of non-standard-sizeopenings, pulled over or around comers, and packed into cracks, around doors and window frames. 3. Permanence--KIMSUL is inherently permanent because it is made of chemically purified wood fibers and asphalt--its last ing qualities are improved by its processing. 4. Will Not Shred or Sift--Each blanket of KIMSUL is composed of many creped layers or plies, strongly stitched together. The fibers are fastened ftimberly'Clark Corporation Imulalion KIMSUL PneMtiiclted BLANKET INSULATION #PHYSICAL PROPERTIES--Cont. 5. Moisture and Fire Resistant--KIM SUL resists water and fire. Even when exposed to flame temperature of 2000 F KlMSUL merely chars. It does not pro duce spontaneous combustion. 6. Lightness--At Standard Thickness (1 in.) KIMSUL has an installed density of 1.57 lb per cu ft. Installed, 1000 sq ft of it weighs only 131 lb. Thus KIMSUL adds relatively little weight to structural load of a building. PROPER THICKNESS FOR AVERAGE REQUIREMENTS To calculate what thickness of insulation will provide the desirable balance between costs and the benefits produced, it is neces sary to have information concerning the specific job. The severity of the climate, the price of the fuel to be used are im portant considerations. In most cases, however, it will be found that the standard one-inch thickness of KIMSUL is not only sufficient but that this thickness stops the greatest proportion of heat losses in winter, and the greatest proportion of heat infiltration in summer, at the least cost. HEAT LOSSES THROUGH WALLS, ATTICS AND ROOFS The effectiveness of KIMSUL in re ducing heat flow varies somewhat, depend ing on type of structure insulated. The Figure at lower left shows relationship between insulation thickness and the heat stopped, expressed as per cent of heat flowing through an uninsulated structure. Note that depending upon the structure insulated, the per cent of heat stopped by Standard Thick KIMSUL varies from 54 per cent to 77 per cent. When a normal frame wall is considered, I in. of KIMSUL stops 54 per cent of heat which would be lost through the uninsu lated wall. By adding another inch of thickness this percentage is increased, to 65 per cent--so the second inch of insu lation is responsible for stopping only an additional 11 per cent. If wall thick insulation is used, total heat stopped is only increased to about 73 per cent. Looking at it another way--by taking the maximum heat stoppage through wall insulation as TOO per cent--1 inch of KIMSUL stops 74 percent of all the heat that can be stopped by insulation. So it is evident that it is the first inch which does the most work. Graph shows how effectively KIMSUL reduces heat flow through typical frame struct ures. Note that greatest pro portion of heat losses are stopped by the first inch of KIMSUL. It must, however, be borne in mind that stopping 75 per cent of the heat losses, by. insulating walls and roof, does not mean a fuel savings of a like amount. Usually half of the wall area is made up of doors and windows and heat losses through them must also be considered. 1043 Insulation Mundet Cork Corporation 65 S. Eleventh St. insulation division Brooklyn, N. Y. Manufacturers of Corkboard, Cork Pipe Covering, Compressed Machinery Isolation Cork, Natural Cork Isolation Mats, Cork Tile, Cork Bulletin Board, and all kinds and varieties of Cork Specialties. Mundet Branches Albanv, N. Y. Atlanta. Ga. Boston (No. Cambridge), Mass. Chicago, III. Cincinnati, Ohio Dallas, Texas Detroit, Mich. Houston. Texas Kansas City, Mo. Los Angeles. Calif. New Orleans. La. Philadelphia, Pa. St. Louis. Mo. San Francisco, Calif. Syracuse, N. Y. , 5 Mundet Distributors are Located in the Following Cities Names and Addresses Sent Promptly on Req est Amana. Iowa Baltimore. Md. Buffalo, N. Y. Charlotte, N. C. Cleveland, Ohio Denver. Colo. Hartford, Conn. Johnson City, Tenn. Memphis, Tenn. Minneapolis, Minn. Nashville. Tenn. Norfolk, Va. Oklahoma City, Okla. Portland, Oregon Providence, R. 1. Richmond, Va. Rochester. N. Y. Salt Lake City. Utah Seattle. Wash. Tucson. Ariz. Tulsa, Okla. Utica, N. Y. Youngstown. Ohio Mundet "Jointite" Corkboard --for all low temperature insulation and for acoustical correction. 100% pure cork, fabricated in accordance with U. S. Government Master Specifications and unsurpassed in its field. Sold in standard 12 in. x 36 in. sheet. Standard thicknesses, in., 1 in., 1J4 in., 2 in., 3 in., 4 in., 6 in. Mundet "Joindte" Cork Pipe Covering Shown below, with fitting cover. Pro tects all types of low temperature lines. Made in 3 thicknesses, with complete line of standard covers, suitable for pipes carrying sub-zero to 50 F temperature. paper applied with hot asphalt top and* bottom. Mundet steel bound mats are usually used under exposed mounts; as phalt paper bound mats under concrete foundations of the envelope type. Mats are made to fit under any type of machine foundation. For loads exceeding 2000 lb per square foot, we manufacture Mundet Machinery Isolation Cork, which is a board form of compressed granulated cork, available in 3 densities. All types of isolation are furnished in 1 in., 1]^ in., 2 in., 3 in., 4 in., and 6 in. thicknesses, depending on class of service. Above close-up of Mundet Natural Cork Isolation Mat shows how the blocks of cork are held together within a steel frame. Section of Mundet Moulded Cork Pipe Covering. with Fitting. The pipe covering is made in sections 86 in. long, to fit all sizes of pipes. Mundet Cork Vibration Isolation Machinery vibration encountered in heating and ventilating work is effectively controlled by the use of Mundet Natural Cork Isolation Mats. These consist of blocks of pure cork, held together within a rigid steel frame or bound with asphalt Engineering and Specification Service Our engineering department is at the service of Architects and Engineers, to^ assist and advise in the preparation of specifications pertaining to cork. This service is also available without obligation to any one who has a low temperature insulation or a vibration isolation problem. Our complete catalogue is filed in Sweet's Architectural Catalogue and will be sent on request. It is replete with information and data of value to every specification writer whose field touches our products. Mundet Contract Service Covers the complete installation of our products, in accordance with best estab lished practice. Divided responsibility is avoided. Ajl materials and workmanship are guaranteed. 1044 Insulation The Pacific Lumber Company PALCO WOOL INSULATION too Bush Street San Francisco 35 E. Wacker Drive Chicago 5225 Wilshire Blvd. Los Angeles 122 East 42nd St. New York iswhat it 8 PROPERTIES PALCO WOOL is a loose fill insulating ma that make it terial made from the bark of the Redwood tree, the AN IDEAL protective covering of the world's oldest living thing. It is highly refined into an TRADE MARK RED. U. $. PAT. OFFICE INSULATION insulating material of light weight, wiry 1. Thermal Efficiency: The estab fibres of springy resilience. Recent im lished conductivity of PALCO WOOL is provements in manufacturing have made .26 Btu per hour per sq ft per inch of it dean, dustless and lighter in weight. In thickness per degree F difference in tem practical use PALCO WOOL has proven perature by the Flat Plate Method. to be ideal for all types of construction, 2.'Non-Settling: The fibres of PALCO large or small, where resistance to conduc WOOL possess such resilience that no set tion of heat is required. It is continuously tlement in a wall can occur under the most efficient and reasonably priced, thus severe conditions of vibration. assuring economical performance. 3. Moisture Resistant: The fibres of USES PALCO WOOL is suitable for any type of domestic or commercial construction as well as for the various types of Cold Storage construction. PALCO WOOL are entirely lacking in capillarity and have little attraction for . moisture, enabling it to remain dry and efficient when in use. 4. Permanent: The inherent anti septic qualities of PALCO WOOL make INSTALLATION Approximately .8 of a lb of PALCO WOOL is required per square foot of 4 in. thickness. It is easily installed by hand or by machine. Between 100 and 150 lbs can be applied per hour per man. It comes in bales weighing approximately 100 lbs. Size 24 in. x 24 in. x 26 in.- the existence of fungus impossible. The fibres retain their resilience indefinitely. 5. Vermin Repellent: PALCO WOOL is distasteful and repellent to rodents and insects. 6. Fire Resistant: PALCO WOOL will not readily support combustion and is fire resistant. - 7. Odor Proof: PALCO WOOL is Send for Insulation Manuals odorless itself and does not absorb or give Send for new 16-page booklets: "For Comfort & Economy" on House Insulation or "Cold Storage Manual." Both give comparative charts and complete infor mation on PALCO WOOL. Free sample off odors. . 8. Economical: PALCO WOOL is light in weight and low in 'density, offering exceptional thermal efficiency' per dollar invested. on request. . House Application Cold Storage Application 1045 New York Insulation The Ruberoid Co. INSULATING PRODUCTS Executive Offices 500 Fifth Avenue, New York, N. Y. Chicago Divisional Offices Boston (Millis) Erjb Baltimore , Mobile The desire for increased efficiency of heating equipment as well as the need for fuel conservation prompts the engineer to seek the product that provides him with the most economical operating plant. The following Ruberoid Insulating Products are tabulated to enable you to choose quickly the one for the correct purpose. Greater detail and description are provided in the Ruberoid-Watson Catalog on "Heat or Cold Insulating Products," which will be sent on request. Product Hi-Temp Pyrfeh Axisto Sponge Felt 85 per cent Magnesia Imperial Watcocell . Air Cell Woolfelt ' Anti-Sweat Frost-proof Temp. Limit to 1600 F to 1000 F to 750 F to 750 F to 600 F to 500 F to 350 F to 350 F to 180 F to 120 F 30 F to 100 F Suggested Use Protective inner layer for low temperature insulations. Breechings and Hues -- withstands vibration. Superlative efficiency particularly on oil refinery lines. For vibrating pipes and underground insulation -- excellent efficiency. Combined efficiency.and reasonable cost -- General use in industrial work For temporary fines that require efficiency and constant removal of insulation. For a low-cost, medium pressure industrial steam line. Standard insulation for residential pipes. For cold and hot water fines. Recommended especially for air conditioning work. For cold water lines to prevent condensation. To assist in the prevention of freezing in circulating water pipes exposed to cold. Air Cell Pipe Covering--A Icnv-cost insulation for rest- - deniial use. - Woolfelt Pipe Covering-- For the .insulation of pipes carrying hot or cold water-- also Prevents condensation under normal operating conditions. Sheet and Block Insulations All of the above products are also made in sheet and block form to whatever thickness may be required. Standard sizes are usually 6, 12,18 or 36 in. wide x 36 in. long. In this form they are used for in sulating flat or irregular surfaces, such as tanks, breechings, furnaces, etc. Insulating Cements For the finishing of sheet and block insulation and the insulating of irregular surfaces, such as valves, unions, flanges, etc., the Ruberoid-Watson line of insu lating cements is complete. This group of plastics not only uses as its base asbestos, but also takes advantage of such excellent natural products as magnesium, mineral wool and Vermiculite. Asbestos Cements--Factory Prepared --Grades AA, A, HF. Asbestos Cements--Mine Run-- Grades 115, 214. Magnesia Cement--85 per cent Mag nesia. High Temperature Cement--Grade H.T. Mineral Wool Cement--Grade R-W. Vermiculite Cement--Grade A-ll. 1046 _ The Ruberoid Co. Insulation RU-BER-OID Asbestos Insulating Papers and Millboard Asbestos Paper Made of pure asbestos fibre and small percentage of binding material. Pos sesses unusual strength. This fine fire-resisting sheet may be obtained in 8, 10, 12, 14. 16 and 32 lb weights--ranging in thick ness from 0.019 to 0.0625 or H6 in. Rolls 18,24 and 36 in. wide, weight 50 or 100 lb. Color, blue white. Asbestos Corrugated Paper Made entirely from high est quality asbestos felt paper by cementing flat sheet firmly with a 34 in. corrugated sheet which forms dead air spaces. Flexible. Efficient for in sulating hot air pipes and ducts. 36 in. wide. Weight approximately 46 lb, 250 sq ft. Asbestos Millboard Asbestos Millboard is a rigid insulating board made of high quality as bestos fibres and nonorganic binder. Has exceptional strength and whiteness. Cuts or drills easily. Standard or em bossed finish. For tem peratures to 1100 F. Sheets 42x48 in. Various thicknesses and weights. RU-BER-OID ROCK WOOL ' Mass or Fill Type Bats--Loose--Granulated This indestructible wool is an efficient insulating material. Absolutely fire proof, vermin proof and inert toward moisture. Affords excellent sound-deadening and acoustical qualities. RU-BER-OID Kraflined Rock Wool Bats are care fully fabricated. They are well tailored, uniform and easily handled. They are clean and sufficiently denseto prevent dusting and de terioration. Each bat is backed with a moistureresistant paper that pre vents the infiltration of vapor into the insulated space, RU-BER-OID Kraf lined Bats provide "four flap" protection--each edge having an extension that allows adjoining bats to be covered preventing any ex- Ciant Bats RU-BER-OID Rock Wool Packages Contain posed seam, thus effectively resisting the vapor flow. Recommended for all ex posed spaces, such as side walls of new houses or under the roof, either in the roof rafters or the floor joist over the top floor ceiling. Bats without the Krafliner can be furnished if desired. . RU-BER-OID Wal-Pac Pads are insulating units 9 in. x 15 in. that can .be fluffed up when applied to nearly .fill the studding space. Furnished in car tons weighing 25 lb con taining 20 pads that should cover 20 sq ft area. RU-BER-QID Loose and Granulated Rock Wool is also available. Furnished in paper bags containing 35 lb each. Kraflined Standard Bat... Kraflined Demi-Bat........... Kraflined Giant Bat........... Kraflined Giant Demi-Bat. 15 in. x 23 in. x wall thickness. 15 in. x 23 in x 2 in. thick........ 15 in. x 48 in. x wall thickness. . 15 in. x 48 in. x 2 in, thick.... 1047 8 bats--19.16 aq ft 27 lb VI bats--28.75 sq ft 30 lb 5 bats--25 sq ft 45 lb 8 bats--40 sq ft 45 lb /nsulation The Standard Lime & Stone Company First National Bank Building Baltimore, Maryland Manufacturers of Capitol Rock Wool Home Insulations Franchised Distributors in all Principal Cities The Standard Lime and Stone Company, prominent in the building materials industry since 1888, manufactures CAPITOL ROCK WOOL INSULATIONS, all types of lime products, fluxing and crushed stone, Capitol Portland Cement, etc. Their new process of manufacturing Capitol Rock Wool produces a refined, longer,, more flexible fibre--resulting in increased insulating efficiency. Capitol Rock Wool in Existing Homes Capitol Rock Wool Grade "A" Blowing Fibre is pneumatically introduced into the wall air spaces and between rafters or joists in roofs or attic floors of existing homes. This "blowing" method of installation is applicable to any type of construction--shingle, clapboard, brick veneer, stucco or half timbered. The instal lation leaves no visible telltale marks. Fran chised blowing contractors install Capitol Rock Wool in accordance with the master specifications of the company's home insu lation engineers. Capitol Rock Wool in New Structures In the past, new homes or buildings were insu lated at the time of erection by placing pre fabricated batts between the studding and between roof rafters. However, many new structures are now effectively insulated by pneumatically installing Capitol Grade "A" Blowing Fibre after the scratch coat of plaster is applied. . I5 I Installing Capitol Rock Wool by Pneumatic Method CAPITOL ROCK WOOL BATTS Installing Capitol Rock Weed Batts in a New Structure Moisture Proofed--Special processing renders fibres moisture-resisting. Vaporproofing Membrane--Protects exposed sur face of the batts against moisture from wet plaster and excessive interior humidity. Tested membrane is en closed separately in each carton. It is 17]/i in. wide and of sufficient length to give a smooth continuous mem brane-protected surface without open joints. Tacking is quick and easy. Cuts Cost--Capitol Batts are semi-rigid--made in one size, 15 in. x 24 in. This semi-rigid feature permits "spring fit" between framing members spaced either 16 in. or 24 in. on centers. Easily cut to fit irregularly shaped spaces. Two Thicknesses--Wall thickness, for maximum efficiency, also 2 in. thickness. Permanency--All Capitol Rock Wool Products are permanent, non-deteriorating. They bring lasting, yearround comfort--fire protection to the home. Fuel sav ings ultimately return the investment many times over. CAPITOL ROCK WOOL IS EFFICIENT The dead-air cell structure of Capitol Rock Wool virtually eliminates the transmission of heat and sound. In addition--CAPITOL ROCK WOOL WILL NOT BURN. Send for Catalogs and Samples of Capitol Rock Wool Home Insulations. "Look for the Capitol Dome on every package." 1048 Insulation United States Gypsum Company 300 West Adams Street, Chicago, Hi. Sales Offices In Principal Cities Inch Blanket PRODUCTS RED TOP INSULATING WOOL Medium Blanket Thick Blanket to the outside (cold side) of the wall. The Description Red Top Insulating Wool is an extremely light wool type of insulation made of silica and other selected minerals. Accurate control of all materials used in the formula flanged vapor barrier provides for fastening the insulation in place and automatically provides an air space between the insu lation and the lath and plaster. assures a uniform material without "shot" Ease of Installation or nonunsulating materials. The fibres have great strength and resiliency and the Red Top Wool Blankets and Bats are wool does not mat or pack. . made to fit snugly in spaces between standard framing. The resiliency of the fiberglas mat allows it to spring back when Low Thermal Conductivity compressed. Easy to apply with a mini The heat conductivity of Red Top Insu mum of cutting. lating Wool (1-H lb density) is 0.26S Btu per inch thickness, per square foot per hour, per degree Fahrenheit difference in temperature. . Permanence Red Top Wool does not deteriorate. It will not sag or pack down. It does not retain moisture. The fiberglas mat is Moisture Proof fireproof. The fibres of Red Top Wool have no affinity for moisture and the finished blankets and bats are so made that it will not retain moisture. Resistant to Condensation Red Top Wool Blankets and Bats are entirely enclosed. The side next to room (warm side) is covered with a vapor barrier. The other sides are enclosed in a porous envelope that permits "breathing" Types Red Top Insulating Wool Blankets and Bats are furnished in one inch thickness, medium thickness and thick to meet various climatic and job conditions. Red Top Wool is also available in small bats not enclosed'*in vapor proof barrier or "breathing" envelope. Red Top Wool for installing by pneumatic equipment is furnished in small pellet form. 'SSSfiUM? Haw Red Top Wool ControU Condensation. How Red Top Wool pro- vides automatic a*r spacing. Insulation Western Felt Works 4029-4117 Ogden Avenue, Chicago, 111. LARGEST INDEPENDENT MANUFACTURERS OF FELT Pittsburgh Detroit New York Cincinnati Branch Offices ' Boston St. Louis Los Angeles Denver Dallas San Francisco Philadelphia Seattle Cleveland Portland Manufacturers and Cutters of Wool, Hair and Jute Felts WESTERN FELT WORKS, as a leading manufacturer and cutter of FELT, operates a thoroughly modern mill and completely equipped cutting department. Com petent and up-to-date research and laboratory technicians are available at all times without obligation, to anyone whose field touches our products. AVAILABLE IN ROLLS, SHEETS OR CUT TO SPECIFICATIpNS--Western Felt products are used most commonly in heating, ventilating and air conditioning installations for eliminating noise transmission and as an insulation against heat losses and cold penetration. . WESTERN FELTS FOR SOUND CONTROL--Noises created by the openition of air conditioning equipment must be entirely eliminated at their source or neutralized and deadened during their course of travel through the air ducts. For such purposes Western Felts are especially adapted for lagging on air ducts, where it does triple duty--as a sound deadener of noises caused by the air conditioner itself--by preventing noises originating outside the system from being transmitted via the air ducts--and, because of its low rate of thermal conductivity, it serves as an insulation against heat losses through the duct structure. CUT TO REQUIRED SHAPES AND SIZES--Western Felts serve efficiently, as shock pads under such machinery as oil burners, stokers, fans, blowers, pumps, etc. Western Felts used in this manner counteract destructive vibrations and the resultant noises which would otherwise pass through air ducts to the various rooms. OTHER USES FOR WESTERN FELTS--Fabricated of wool, hair, or jute, Western Felts are available for a wide variety of other uses, such as weatherstrips, anti-squeak strips, insulation material, gaskets, washers, packing material, floor pads--in sheets, rolls or cut to special requirements. Important is the use of felt strips as a dust seal between the room register and wall. APPLICATION OF WESTERN FELT--Strength of fibre, flexibility and easy working characteristics of Western Felts make them simple to handle. Flat surfaces or irregular contours are easily and quickly covered at low labor cost. ADHESIVE COATED FELT--A new idea in felt which eliminates the old glueing method--adhesive coating which adheres to either metal or wood. Used extensively for streak proof installations on registers and grilles. Write for free samples and further information describing the use of Western Felts for air conditioning units, or other purposes. Showing how Western Felt is used as mounting material at base oj motor and blower units to reduce vibration and subdue noises. 1050 Insulation Wood Conversion Company First National Bank Building, St. Paul, Minn. New York Chicago Tacoma Dallas BALSAM-WOOL AND NU-WOOD INSULATIONS balsam-wool Sealed Insulation Acoustical Blanket Sound Deadening Industrial Insulation Refrigerator Insulation NU-WOOD Tile Plank Board Wainscot Sheathing NU-WOOD Lath Roof Insulation Industrial Insulation Refrigerator Insulation < KOLOR-TRIM Pre-decorated Moldings BALSAM-WOOL--The Original Moisture Barrier Insulation The Moisture Barrier, which is universally recom mended by engineers and architects, has been incor porated in Balsam-Wool for 17 years. This Barrier, improved as construction and equipment demanded, now consists of double layers of asphalted kraft--a heavier liner being used on the warm side. Encased between this protective covering is an insulating mat of fleecy wood fibres, chemically treated to resist fire, rot, termites and vermin. 92 per cent of the mat volume is dead air. Balsam-Wool SEALED Insulation is fabricated at. the factory to a controlled density of 2.2 lb per cubic foot. The mat has a coefficient of .25 Btu per hour, per square foot, per 1 degree F difference, in tem perature, per 1 in. thickness. Balsam-Wool Spacer Flange* As applied, factory efficiency is assured. The Spacer Flange* on each edge folds over and is fastened to framing members with a staple hammer, assuring important air space, front and back. Balsam-Wool is available in x/i and 1 in. thick nesses in widths of 12, 16, 20, 24 and 33 in.--Wall- thick in widths of 12, 16, 20 and 24 in. *Pat. Applied For. . Application is quick and easy NU-WOOD INTERIOR FINISH ^ STRUCTURAL INSULATION Nu-Wood Interior Finish (Tile, Plank, Board and Wainscot) is applicable either to new construction or to existing build ings. It offers varied and pleasing dec oration, also insulation and acoustical value. Nu-Wood Insulating Lath has several times the bonding strength of wood lath-- continuous surface eliminates dirty lath marks, reduces cracks. V-joint resists trowel pressure in both directions--assures unbroken insulation value. Nu-Wood Insulating Sheathing is , surfaced on both sides with double coats of special moisture proofing compound. Large boards, marked for nailing--speed erec tion--stronger, windproof, insulated con struction. 1051 Publications Heating Ventilating Air Conditioning Guide 51 Madison Ave., New York, N. Y. Published Annually by of andThe American Society Heating Ventilating Engineers FUNDAMENTAL FACTS FOR THE PROFESSION Established in the year 1922, The Guide, now in its eighteenth edition, has since continuously served the profession and the industry--by impartial research and compilation of engineering data, and the presentation of factual data on apparatus and materials used in heating, ventilating and air conditioning. Constantly broadening in scope, The Guide has grown from a small volume of 360 pages, in 1922, to its present size of 1184 pages in this the 1940 edition. The Guide has two main sections--a Technical Data Section containing 46 chapters of engineering data and general information, compiled by men expert in their respective fields; and a Catalog Data Section containing 5 divisions and describing the products of manufacturers in this field. The contents of both sec tions are fully indexed for convenient reference. The price of The Guide is $5.00. (Special Thumb-Index Edition $5.50). THE REFERENCE BOOK OF AN INDUSTRY The widespread acceptance of The Guide as a reference book is indicated by the occupations of the men who use it. They include: The entire membership of The Ameri can Society of Heating and Ventilat ing Engineers--now numbering 3147 and composed of engineers, architects, contrac tors, manufacturers, and men in other branches of the profession and the industry. Members of the American Institute of Architects--who utilize the information, contained in The Guide to coordinate their work with heating, ventilating and air conditioning requirements. Members of the American Society of Re frigerating Engineers--a profession closely allied with the cooling phases of air conditioning. Members of the Heating, Piping and Air Conditioning Contractors National Associ ation--men actively engaged in the pur chase and installation of equipment and materials. And thousands of other men engaged in all branches of the profession and the industry, but not members of the organi zations dominant in their respective fields. That these users of The Guide com prise a valuable potential market for heating, ventilating an3 air conditioning equipment has been recognized by manu facturers. Year after year many of them use space in the Catalog Data Section to describe their products and have the ad vantage of this close contact with men who influence purchase of equipment. DISTRIBUTION The distribution of The Guide is inter national and includes the United States, Canada, and 34 foreign countries. A classified analysis of Guide users and their geographical location will .he sent to inter ested manufacturers upon .request. . 1052 PUBLICATIONS Important to the field of heating, ventilating and air conditioning are the technical journals, trade papers and business publications serving these industries. They include regular monthly editions, special annual numbers and trade catalogs issued by commercial publishers; and many periodical and annual editions published by engineering societies and trade associations. These publications are a year-round source of information on the many problems involved in the design, production, distribution, operation and maintenance of heating, ventilating and air conditioning equipment, and related problems in refrigeration. In editorial content and in their advertising pages are given a comprehensive review of developments in their respective branches of the industry. By means of scientific and technical articles they disseminate information of value---they provide valuable data for the engineer, practical helps for the production man, and also serve the distributor, dealer, contractor, and the operating and maintenance man. PUBLICATIONS (p. 938, 1052-1063) Specialized trade papers serving a specific branch of the industry; general publications serving the broader field of the entire industry and profession; and technical publica tions'providing the data necessary for scientific development of the industry. Many publications compile market statistics and provide merchandising sug gestions for their readers. These services are of value not only to their readers,' but are important to manufacturers who advertise their products in the pages of these publications. ' Consistently read--and their contents correlated with private and govern mental data bn development and distribution of heating, ventilating and air conditioning equipment--these publications afford a comprehensive under-, standing'of the problems and progress of the industry as a whole. 1053 Publications 232 Madison Ave. Lex. 2-4566 Chicago 903 Merchandise Mart Delaware 9389 San Francisco Don Haeway & Co. 155 Montgomery St. Exbrook 6029 Los Angeles Don Harway & Co. 318 W. Ninth St. Tucker 9706 New York, N. Y. Baltimore Candler Bldg. Plaza 7065 \ stablished in 1928, this publi Your Questions About Winter Air Con E cation was known as "OIL HEAT" ditioning"--16 pages; many reprints of its first 7 years and covered the manuarticles on Service, Designs, etc. facture, sale, installation and servicing of For Sale; January, 1940, Annual Fore oil burners and oil-fired units. In 1935 its cast and Statistical Issue--a Report on title was changed to its present form and 1939 and previous years, very complete, the editorial content expanded to cover air accurate and interesting--$1; "Summer conditioning and heating as well as oil Air Conditioning," 28 pages of instruction burners. This inspired and kept pace with for dealers--$1; "Oil Burner Service," 28 the field itself. pages of valuable data and information-- The oil burner manufacturers and SI; "Oil Burner Installation," 32 pages-- dealers are a naturally progressive group, the best thing of its kind published--SI; else they would not have engaged in the "Directory of Oil Burner and Air Con challenging new oil burner business in the ditioning Manufacturers," -- equipment first place. They understood and could specifications, officers and trade names, etc. handle the modern technical and mer chandising problems presented by the sale - Circulation of this paper: of air conditioning equipment and, joined by an increasing group of similarly alert business men, they entered into air con Combination Power Oil Burner and Air Con ditioning Dealers..............-.............................. 7,094 Additional Oil Burner Dealers (not yet hand ling air conditioning)_________ _____ _____- 5,774 ditioning activity with characteristic vigor and success. They found, then, and still find, all they require of "literature of the Additional Air Conditioning Dealers (not now handling oil burners)........... -................. ........ Wholesalers and distributors of air condition ing. oil burner and heating supplies and 685 art" in this paper. Today (Dec. 6, 1939) 46.3 per cent of the oil burner manufacturers are also in accessories............................................................ 1,205 Manufacturers, Executives, Branch Offices and Field Men--oil burner and air con ditioning.......... ..................... ............................v. 715 the air conditioning business, and 54.3 per cent or 7,094 out of the country's total of 12,868 oil burner dealers, are also in the air conditioning business. * Editorial articles cover such sub Accessory Manufacturers--oil burner and air conditioning........................................................ Air Conditioning Departments of Public Utilities................................................................. Advertisers, Agencies, etc................................... Unclassified--........:................................. ............ Office, Files................ . 299 408 10 583 410 jects as "Summer Air Conditioning Total................................................. -.............17.158 Sales, Installation, Service;" "Oil Burner Manufacturing, Distributing, "MARKETING NEWS-BULLETIN" Selling, Installing and Servicing Prob a bi-monthly publication issued by Urns;" "Degree-Day Charts--a ^Jiis organization, covered 57 cities monthly service, showing heating and communities, giving sales of mi- loads in various cities;" "Heating burners, stokers and gas- burners in Equipment Sales and Installation many of them, by trade names. Problems;" "Winter Air Conditioning Other data, local and national, was Questions--Designs, Ducts, Sales, included. Available only to sales and Servicing;" "Retail and National Mar advertising executives. Price $10 per ket Studies;" "Boiler, Furnace and year; $2.50 per copy. Sample copy on Accessory Equipment Operation;" request if you qualify. "Humidification;" "Summer Cooling Hours--a monthly service showing Advertisers find AIR CONDITION cooling load for various cities (an ex ING & OIL HEAT a profitable medium clusive feature);" Complete coverage of in which to cover the field with their the Industry's Activities Each Month. message. Readers respect its progressive Subscription Price S3 a year; 12 issues. and trustworthy editorials, and responds very well to its advertising pages. Send Booklets and publications available: for a sample copy. "What the Air Conditioning- Oil Burner Dealers are Thinking and Doing about We also have a "Direct Mall Service" Sheet Metal Shops, Ducts, Registers, under which literature may be mailed Blowers, Etc.--"16 pages; "Answers to to the groups of readers shown above. 1054 Publications Coal-Heat Published at 20 W. Jackson Blvd., Chicago, Illinois FOR reliable infor mation about small stokers, read COAL-BEAT, The Stoker Magazine. Since the inception of the household stoker industry, COALHEAT has been its acknowledged medi um and it's most active proponent. COAL-HEAT readers include the men who design, manufacture, sell and service over 80 per cent of the household and commercial stokers in the coun try. The largest group of these men are coal merchants, but many are also heating contractors, furnace and air con ditioning dealers, and electrical appliance dealers. COAL-HEAT'S primary editorial job has been and is "to further the more satis factory use and sale of coal and modern coal-burning equipment." COAL-HEAT has been an active exponent of the greater use of scientific and engineering knowledge in the application and sale of stokers, coal and heating equipment. Editorially, COAL-HEAT is convinced of the engineer's growning significance in the coal stoker and heating industries, and for this reason, it has carried, year in and year out, many articles for and by fuel and heating engineers. COAL-HEAT has long since recognized the mutual and reciprocal interests of the coal, stoker, heating and air conditioning industries. It has given particular at tention, editorially and otherwise, to the "equipment factor" in the use of coal. To those manufacturers who have recognized the value of coal and stoker dealers as outlets for various types of heating and air conditioning equipment, COAL-HEAT has become a most effective advertising medi um. Today, it carries more stoker and stoker accessory advertising than all other trade publications combined, and more stoker coal advertising than any other single magazine. With 569,000 stokers in use, COAL-HEAT'S market is apparent. COAL-HEAT is published on or about the I5th of each month. There are four special issues each year -- the MARKET DATA ISSUE in January; the SPRING STOK ER NUMBER in April; the ANNUAL MERCHANDIS ING NUMBER in August; and the AN NUAL COMBUS TION NUMBER in November. The January MARKET DATA ISSUE is especially noteworthy inasmuch as it carries many helpful and interesting graphs, charts and articles containing considerable informa tion and significant sales data about the stoker and coal markets and pertinent phases of the heating and air conditioning industries. At the beginning of each year COALHEAT issues a new and revised list of stoker manufacturers and assemblers doing business in the United States, Canada and certain important foreign countries. Each listing includes the name of the company and the address, the executive in charge, the trade name of the stoker, the types and sizes of units available, and whether they are manufactured, assembled or handled as a "private brand" line. COAL-HEAT also publishes books, booklets, manuals and reprints covering many subjects of interest to men in the stoker, coal and heating industries. These are available to readers at a small cost. In every respect, COAL-HEAT is a valu able index to what is going on in these important fields and a source of con siderable information to its readers. Subscription rates--$1.00 a year; $2.00 for three years in U.S. and Canada. Foreign rates--$2.00 a year; $4.00 for three years. . Advertising rates will be furnished upon request. 1055 'S'TTaF* / Publications American Artisan Published by KEENEY PUBLISHING COMPANY 6 North Michigan Avenue, Chicago, 111. __________________________________ __ \ merican AARTISAN, now in its 61st year of publication, covers the field of warm air heat ing, residential air con ditioning, and sheet metal contracting. A special section of each issue has been devoted to air conditioning since 1932, when it first became apparent that air. conditioning for homes was to be along the lines of the central, forced warm air heat ing system. Its readers are warm air heating and sheet metal contractors, dealers, jobbers and manufacturers, and also architects, engi neers, and public utility companies who take it for its thorough coverage of air conditioning for the home field. To answer the industry's need for a dependable guide to equipment pur chases, it publishes in each January issue a complete and up-to-the-minute directory of warm air heating, air con ditioning and sheet metal products and equipment. This directory lists all products used in the field, their trade names, and the full names and addresses of all manufacturers. It is used by readers as a buying reference throughout the year. Almost from the day interest in resi dential air conditioning began to develop, the advantages of the warm air type of heating system, with its duct distribution of air, were plain to see. It was adapted to all air conditioning factors, either through a self-contained central unit or through a central furnace to which could be added step-by-step or as a whole, fan, washer, humidifier, filters, controls, cooling, and automatic firing. Today, as a result of this ready adapta bility as well as economy, tens of thousands of homes have winter air conditioning-- supplied through forced warm air heating with air cleaning and hu midification. Cooling apparatus can be at tached to these sys tems readily whenever complete, year-'round air conditioning is de sired. This, trend in resi dential air conditioning has placed a premium on air handling know ledge, and has brought to the fore the one man experienced in "treat ing" air at a central place and getting it properly distributed-- the warm air heating and sheet metal con tractor. The warm air heating industry has, furthermore, undertaken and made notable progress toward the solution of the many new engineering problems involved. All this has helped to put warm air heating in the center of residential air conditioning. In aiding to develop this trend and assist in the solution of new problems, AMERICAN ARTISAN has provided a service to its field which has made it the recognized authority on residential air conditioning practice. . To manufacturers whose products are used in residential air conditioning, AMERICAN ARTISAN offers full cover age of the leading buying factors. Such manufacturers will be interested in the market study called "What's What and Who's Who in Air Conditioning." For further information about this study, write to the address above. AMERICAN ARTISAN is published monthly. It is a member of the A. B. C. and A. B. P. Subscription rates--$2.00 per year, $3.00 for two years in V. S., Canada, Mexico, Central and South America. Foreign $4-00 per year. Advertising rates furnished upon request. 1056 Publications Heating, Piping and Air Conditioning Published by . KEENEY PUBLISHING COMPANY 6 North Michigan Avenue, Chicago, III. eating, Piping Hand Air Con ditioning is the pub lication which carries in each issue the official Journal of the American Society of Heating and Venti lating Engineers in addition to its own regular editorial sec tion. Its field is that of industry and large buildings. Editorially, it gives specialized at tention to the design, installation, operation, and maintenance of heating, piping, and air conditioning' sys tems in such plants and buildings. In addition, there is published in each January issue a complete Directory of Commercial and Industrial Heating. Piping and Air Conditioning Equipment, which lists all products used in the held, their trade names, and the full names and addresses of all manufacturers. This directory has been established as the industry's buying and specifying guide, and is consulted by readers throughout the year, whenever equipment purchases are up for consideration. H. P. & A. G. is read by consulting engineers and architects . . . contractors . . . arid engineers in charge of heating, piping, and air conditioning in industrial plants, large commercial and public buildings, federal, state, and city govern ments, school boards and public utilities. Among its subscribers are numbered all members of the A.S.H.V.E., who represent about 30 per cent of its total circulation. Such a coverage means, for the adver tiser, consideration at all points in the selling of a heating, piping, or air con ditioning product . . . consideration in the selection of a product during the pre paration of plans and specifications; con sideration in the actual purchase of a product for installation; consideration in the year 'round buying of a product for oper ating and maintenance requirements. It has been evident for some time that the air conditioning field is made up of two dis tinct markets: (1) In dustrial and Commer cial; (2) Residential. These two markets are different in equip ment used; different in engineering prob lems involved, dif ferent in engineering, distributing, and con suming personnel . . . require, therefore, dif ferent selling jobs. To sell the indus trial and large building field for air conditioning, the manufacturer must win acceptance from the engineers who design, specify, install, operate, and select the system to meet the particular requirements of the plant or building. The system may be central, unit, or "split," but it is these engineers who are the in fluencing or purchasing factors. It is to such groups that Heating, Piping and Air Conditioning editorially caters--exclusively in the industrial and large building field. Without waste, the manufacturer of air conditioning products and accessory equipment, such as motors, drives, controls, etc., can reach through its pages those from whom he is seeking the necessary engineering acceptance. These facts are clearly shown in a recently prepared market study titled "What's What and Who's Who in Air Conditioning" which will be presented to interested manufacturers upon request. Heating, Piping and Air Conditioning is a member of the A. B. C. and A. B. P. Subscription rates--SS.00 per year; $8.00 for two years in V. S., Canada, Mexico, Central and South America. Foreign, $4-00 per year. Advertising rates furnished upon request. 1057 Publications Domestic Engineering Publications 1900 Prairie Avenue Chicago, Illinois DOMESTIC ENGINEERING The year 1939 marked the fiftieth anniversary of Domestic Engineering's continuous and outstanding service to its industry. Since its founding in 1889, Domestic Engineering has maintained its position of leadership ... a leadership which was achieved through its background of experience and through its many notable accomplishments during the intervening years. Each month Domestic Engineering reaches the top group of contractor-dealers who are responsible for the major portion of sales made in the plumb ing, heating and air conditioning field. It is to Domestic Engineering that these men look as the authority in their industry. It is to Domestic Engi neering that these men look to keep themselves con stantly abreast of all matters pertaining to their business. To the manufacturer of plumbing, heating and air conditioning equipment, Domestic Engineering, with its well-seasoned background, presents an ideal setting for his advertising program. Write for complete data on Domestic Engineering and the field it serves. PLUMBING AND HEATING NEWS Plumbing and Heating News supple ments and further expands the service of Domestic Engineering to its industry. In mid-month it brings to the major portion of the field all of the latest news develop ments in the industry as well as an exten sive summary of new and improved pro ducts. In this respect Plumbing and Heating News has come to be accepted as the newspaper of its industry. ; The broad coverage of Plumbing and Heating News includes virtually all known buying factors from every branch of the industry. Through Plumbing and Heating News the manufacturer of plumbing and heating products is enabled to reach his largest, most receptive audi? ence at comparatively small cost. Large page and unit sizes make it possible to do a dominating, though economical job. Your inquiry regarding rates and other details is invited. 1058 Publications Domestic Engineering Publications J900 Prairie Avenue Chicago, Illinois AUTOMATIC HEAT and AIR CONDITIONING Automatic Heat and Air Conditioning is de signed primarily to serve the contractor-dealer in the automatic heat and air conditioning field. Included in its wide coverage are the complete line dealers handling summer and winter air condi tioning equipment, oil burners, stokers and gas heating equipment. Also the wholesalers or distri butors in the field, the consulting engineers, the merchandising departments of utilities, and all. known manufacturers are reached each month. In Automatic Heat and Air Conditioning the men in this field find complete editorial coverage of engineering, management and merchandising prob lems pertaining to all types of equipment in the field. Because the complete line dealer has proven most successful and Automatic Heat and Air Conditioning is the one publication designed pri marily to serve this type of outlet, its advertising pages have proven highly productive to manu facturers in the automatic heat and air conditioning field. Total distribution exceeds 15,000 copies each month. Full details gladly furnished on request. DOMESTIC ENGINEERING CATALOG DIRECTORY and AIR CONDITIONING BLUE BOOK A complete buying and specifying guide on plumbing, heating, air conditioning and related equipment. It is specifically designed for and used by buyers, specifiers, speci fying engineers, wholesalers, general contractors and air conditioning consulting engi neers. The data contained in Domestic Engineering Catalog Directory and Air Conditioning Blue Book is arranged in such a way as to make information instantly accessible at a moment's notice. The 1940 Edition of Domestic Engineering Catalog Directory and Air Conditioning Blue Book contains five distinct sections: Manufac turers' Catalog Section--Up-to-the-minute pur chasing and specifying information on products used in this industry. Tables and Rules Section-- Condensed specifying data in form of standard Tables, Rules, Charts and Layout Diagrams on plumbing, heating and air conditioning. Classified . Directory Section--Listing virtually every known product in the industry. Trade Name Section-- Trade names of products used in this field, the items to which they apply and also names and addresses of the manufacturers who make them. Name and Address Section--Includes names and addresses of all known manufacturers in the industry. Because Domestic Engineering Catalog Di rectory and Air Conditioning Blue Book is-in constant use by leading plumbing, heating and air conditioning buyers and specifying engineers, it offers manufacturers an ideal method of presenting product information before the right men in the industry. Descriptive booklet will be sent to manufacturers upon request. 1059 Publications OILHEAjflNG/fr / AIR/oNBITINING' fueloil JOURNAL Published Monthly at 420 Madison Avenue New York MARKET: The oilheating market is a OILHEATING & AIRCONDITION closely knit 4-way market--oilburners, ING: Fueloil Journal covers this inte heating, airconditioning, and fueloil. The grated 4-way market. modern and progressive oilheating dealer It is the oldest paper in the field-- sells all four--a good oilbumer, using good established 1922. Editorially, it has con fueloil, firing a good heating or aircon sistently fostered every progressive de ditioning system. velopment in the field and it has encouraged From 1919 to 1930, the only oilheating the trend to the complete oilheating dealer. product sold by burner dealers was the Every issue is carefully balanced edi conversion burner. In 1930 the sale of torially to. cover the dealers' need for conversion burners represented 77.3 per usable information on all four sides of his cent of the dealers' gross income. business. . By the end of 1938, the average oil Heating equipment manufacturers have heating dealer got only 28.7 per cent of long known Fueloil Journal as a power his income from conversion burners. But, ful sales aid. Its reader interest is unique beginning in 1932, he had added three among trade papers. other major oilheating lines--heating, fuel :circulation Like its editorial content, oil and winter airconditioning. 1938 the circulation of Fueloil Journal is gross dollar volume of the average dealer carefully controlled to give complete cover was divided: age of this great 4-way market. A detailed Conversion burner units........28.7 per cent Heating equipment, in cluding boiler-burner units.,26.2 per cent Fueloil........... ......................... 28.5 per cent breakdown from the latest circulation statement (June-30p-X939) shows: Power oilheating and airconditioning dealers and distributors... 11,905 Key heating contractors, plumbing Winter airconditioning, including furnace-burner and heating contractors, and engi neers 54 Fueloil distributors, selling fueloil and units........................................ 16.6 percent range oil, and their branches_______2,952 In 1938,42 per cent or 57,141 conversion oilburners were sold with new cast iron or steel boilers. In addition, dealers sold 10,934 boiler-burner units. Total boiler sales by oilheating dealers increased 11 percent over 1937. These dealers did a winter airconditioning dollar volume in 1938 of $21,324,383. Accessory and heating supply dis tributors; 1,081 Total dealers and distributors________ Power oilheating and airconditioning manufacturers and their executives, Accessory manufacturers_________ ;____ 15,992 . 634 298 Total manufacturers_____________ _____ Total dealers and manufacturers, Per cent of total circulation__:_____ 924 16,916 98.91 SERVICES FOR ADVERTISERS Other miscellaneous-__________________ 194 Key Market Studies. Grand total..-______ ___________________ 17,110 Merchandising News. Specific Products Reports. Unit Sale Brand Preference Studies. Booklets, reprints of special articles. Fueloil Journal circulation covers the oil heating and air conditioning field at the minimum rate per thousand copies. It will pay you well to get full details. Write, wire or telephone. 1060 Publications HEATING 6-- VENTI LATINO 'w AIR CONDITIONING THE INDUSTRIAL PRESS.. . Publisher 140-148 Lafayette St. New York, N. Y. Heating & VENTILATING reaches the "key HEATINGS clude Degree Days and unit fuel con sumptions for win ter and a record of .VENTILATINGmen" of the indus try--the engineers, Degree-Hours for the hot months in contractors, and ... important cities. equipment manu AIR CONDITIONING Two pages of Refer facturers who have ence Data appear the final word in th$ monthly. specification, instal Every January lation, production issue is devoted to a and maintenance review of events and of mechanical equipment of inter equipment for est during the heating, air condi preceding twelve tioning and venti months, while from lating. time to time special An alert, authori issues and special tative editorial pro editorial sections gram directed by are included to qualified heating cover timely trends. and ventilating Notable in this re engineers assures spect is a special reader acceptance issue devoted to and continuous in apartment build terest. Regular fea ings scheduled to tures include news, trends, developments, appear in the July 1940 issue. This is personalities. In each issue a section is de illustrative of the care with which any voted to a comprehensive and concise re major trend in building types or construc port of New Equipment. Other features in tion is followed editorially. CIRCULATION HEATING & VENTILATING'S total distribution (May 1939)--10,124, classified as follows: Consulting Engineers (535) and Ar chitects (152) Engineers Employed by Consulting Engineers and Architects (178)............................. 865 Contractors (2046) and Engineers Employed by Contractors (400).... 2,446 Employees (806) and Designing Engineers (411)................... ;......... 1,217 Manufacturers'. Agents and SalesEngineering Firms (177), Sales Engineers and Salesmen (796)___ 973 Wholesalers (89) and Dealers (347).. 436 Educational Institutions, Public Li- . braries, Associations...................... 587 Miscellaneous and unclassified......... 685 Governments and School Boards, and their Engineers...................... Public Utility Group......................... Industrial Firms, their Engineers, etc. Buildings, Real Estate Management Companies, their Engineers........... Manufacturers of Air Conditioning, Heating, Piping and Ventilating Equipment, Their Officials and 487 691 825 571 "9,783 Field Staff, Correspondents, Ex changes and Advertising Agencies 341 TOTAL............................................ .10,124 Subscriptions to HEATING & VENTI LATING are $2.00 a year. Advertising rate cards, sample copies and market data will gladly be submitted on request. 1061 Publications Plumbing and Heating Journal Published by THE ANGUS CO., INC. 515 Madison Ave., New York City I LUMBING and Heating Journal is edited to furnish a. well-rounded, efficient service to the men engaged in the plumbing, heating, venti lating and air conditioning fields. To this end, it covers both the technical and business phases of their work, as well as many minor but exceed ingly important ones. It gives free technical service through a staff of practical engineers; expert merchandising assistance, and its technical and business articles are by men of recognized competence. Thousands of readers come to THE JOURNAL each year for solutions to their technical problems and while some of the questions and answers are published in the Readers' Technical Service section in each issue of the magazine, the vast majority of them--having to do with practically every phase of heating, ventilating and air conditioning as well as plumbing--are answered by mail, because most of the requests for help are urgent and a delay in answering would, in some cases, entail actual monetary loss to the contractor. The Readers' Technical Service Depart ment of THE JOURNAL is staffed by editors who have spent their lives in the business; men who were successful plumb ing, heating, ventilating and air con ditioning engineers before they wrote a line for publication, and who now devote their entire time to keeping abreast of the field's technical developments and using their knowledge and experience for the benefit of JOURNAL subscribers. The technical service rendered its readers by THE JOURNAL is closely paralleled by what it strives to do for them in a business way, for it also publishes many authoritative articles on and answers questions concerning the various ramifications of business management and prints as part of every issue, special articles de voted to selling. The JOURNAL'S air conditioning articles are of special value to plumb ing-heating contractors. They stress the potentiali ties in this field, with the express intent of increasing air conditioning instal lations. Supplementing the busi ness and technical articles is a large amount of exclusive, staff-gathered news that high lights the background of the trade's activities. $ This news background is vital; It com pletes the industrial picture for the reader. It keeps him irfintimate touch with what the various important associations and his fellow members of the craft are doing throughout the nation and it charts the trends that are likely to have a very definite influence on the future operation of his business. THE JOURNAL editorial department draws its news from over a hundred trained correspondents located at strategic points throughout the country--by far the largest group of . exclusively editorial workers used by any paper in the industry. In this combination of the technical, business and news aspects of the industry that enables THE JOURNAL to achieve a finely balanced magazine that gives the reader the type of information he wants and needs, in brief, compact, time-saving form. THE JOURNAL is a member of the A. B. C., and costs $2.00 per year by subscription. . 1062 i Publications Sheet Metal Worker Published by Edwin A. Scott Publishing Company * 45 West 45th Street New York THE January 1940 issue of Sheet Metal Worker will be its Sixty-Sixth Anni versary and Directory Number. It is the old est publication in its field and is of vital im portance to men in terested in sheet metal work--air conditioning --warm-air heating and ventilation. Founded and published to 1909 by David Williams Company; 1909 to 1920 by United Publishers Corp.; since. 1920 by the present publisher, the Edwin A. Scott Publishing Co. Sheet Metal Worker is today a monthly merchandising, business and tech nical journal basic to the use of sheet metal. It serves the various unified mer chandising and installing branches of the industry, consuming sheet metal for the erection, maintenance and operating equip ment of homes and buildings, including central air conditioning equipment, warmair heating, ventilating, dust and refuse removal, and systems for handling material by air; kitchen and restaurant work; a wide variety of interior and exterior work for commercial, industrial, institutional, and residential buildings. Subscribers are mainly merchandising contractors purchasing practically all pro ducts and equipment which they fabricate, erect or install. Manufacturers, jobbers and distributors also subscribe. The market has three main divisions: (1) Equipment for resale in connection with erection or installation work. (2) Materials for fabrication. (3) - Shop, equipment and supplies. CIRCULATION Sheet Metal Worker is a member of the Audit Bureau of Circulations and the Associated Business Papers. It has a uni form distribution, with the greater part of its circulation centered in states showing the greatest industrial ac tivity. Readers of Sheet Metal Worker are made up of warm- air heating, air condi tioning and sheet metal contractors and dealers. Also wholesalers, manufacturers, branch offices and salesmen. For further details send for ABC statement. - EDITORIAL Sheet Metal Worker has been out standing in the editorial service it has rendered the trade and is noted for the practical usefulness of its articles and the timeliness of its editorials. Its editor is a noted author in. this field and the author of several well-known books. Sheet Metal Worker also publishes books on heating, ventilating, sheet metal work, air conditioning, etc. ' The Annual Issue published in January, contains a comprehensive and valuable Directory Section. ADVERTISING Sheet Metal Worker has an enviable record of long term advertising and is proud of its long list of regular advertisers. Because of its intimate contact with this field, Sheet Metal Worker is well quali fied to cooperate with manufacturers in their sales and advertising programs^ Subscription rates--$2.00 per year, U.S., Mexico and Canada; Foreign, $3.00. Advertising rates on request 1063 In the Index to Modern Equipment are com plete detailed listings of heating, ventilating and air conditioning equipment and materials. Arranged alphabetically according to names of products are more than 300 items listing not only those products shown in the Catalog Data Section but also many other products made by the manufacturers represented in The Guide. On pages 1065-1088, under each index head ing--Air Cleaning Equipment, Fans, Humidi fiers, Ventilators, etc.--will be found, fully cross-indexed, a complete list of manufacturers of any desired products and page numbers in the Catalog Data Section where the products are described. By reference to these index headings, the manufacturers names and the page numbers, any item of equipment or ma terials may be located quickly. On page 794 are page references to the various sub-divisions of 'manufacturers catalog data, and on pages 795-800 will be found an alpha betical list of manufacturers whose products are shown in the Catalog Data Section. i INDEX TO MODERN EQUIPMENT Heating, Ventilating, Air Conditioning Guide, 1940 air cleaning equipment (See also Filters, Air) Air-Maze Corporation, 844-845 Airtemp Div. Chrysler Corp.', 812- Brunner Manufacturing Co.. 867 Carbondale Div., Worthington Pump & Machinery Corp., 874 875 Carrier Corporation, 804 Baker Ice Machine Co.. 866 Bayley Blower Company, 880 Binks Manufacturing Co.. 858-859 Buffalo Forge Company, 881 Carbondale Div., Worthington Clarage Fan Company. 805 American Air Filter Co., Inc., 846 Crane Company, 968-969 Pump & Machinery Corp., 874 875 847 American Blower Corp., 802-803 American Hair & Felt Co., 1024 American Radiator & Standard Sanitary Corp., 962-965 Autovent Fan & Blower Co., 877 Binks Manufacturing Co., 858-859 Buffalo Forge Company, 881 Curtis Refrigerating Machine Co., Div. Curtis Manufacturing Co., 868 Davies Air Filter Corp., 849 Delco Appliance Div., General Motors Sales Corp.. 814-815 C. A. Dunham Co., 942-943 Fedders Manufacturing Co., 828 Carrier Corporation, 804 Chicago Pump Co., 997 Clarage Fan Company, 805 Curtis Refrigerating Machine Co., Div. of Curtis Mfg. Co., 868 Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Oarage Fan Company. 805 Coppus Engineering Corp., 848 Davies Air Filter Corp., 849 Delco Appliance uiv.. General Motors Sales Corp., 814-815 ' Fitzgibbons Boiler Co., 970-971 Frick Co., (Inc.), 869 Gar Wood Industries, Inc., 818-819 General Electric Co., 816-817, 892 893 Fedders Manufacturing Co., 828 Fitzgibbons Boiler Co., 970-971 Frick Company, 869 General Electric Co.. 816^817, 892 893 C. A. Dunham Co.. 942-943 General Refrigeration Corp., 870 General Refrigeration Corp., 870 Fitzgibbons Boiler Co , 970-971 Grinnell Co., Inc., 944-946, 1007 Grinnell Co., Inc., 944-946, 1007 Gar Wood Industries, Inc., 818-819 Henry Furnace & Foundry Co., 822 Henry Furnace & Foundry Co., 822 General Electric Co., 816-817, 892 Ilg Electric Ventilating Co., 884 Ilg Electric Ventilating Co., 884 893 F. Jaden Manufacturing Co., 829 F. Jaden Manufacturing Co., 829 Martocello, Jos. A. & Co., 861 Kewanee Boiler Corp., 974-977 Mariey Company, 860 L. J. Mueller Furnace Co..-824-825 Lau Blower Co., 885 Mario Coil Company. 871 Owens-Coming Fiberglas Corp., McCord Radiator & Mfg. Co., 834 McCord Radiator & Mfg. Co.. 834 850-851 Parks-Cramer Company, 807 Mario Coil Company, 871 McQuay, Incorporated. 830-831 McQuay, Incorporated, 830-831 Modine Mfg. Co.. 832-833 H. J. Somers, Inc., 854 Staynew Filter Corp., 852-853 B. F. Sturtevant Co., 886 Unit Heater and Cooler Co., 840 United States Air Conditioning Meyer Furnace Company. 823 Modine Mfg. Co.. 832-833 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 J. J. Nesbitt, Inc., 8o6 Herman Nelson Corp., 835 J. J. Nesbitt, Inc., 836 Niagara Blower Company, 806 Parks-Cramer Company, 807 Refrigeration Economics Co., 837 Corp.. 810 . ^ Westinghouse Elec. & Mfg. Co., flfiA-RnQ ftS5 Niagara Blower Company, 806 Parks-Cramer Co.. 807 Pocahontas Fuel Co.. 826 Refrigeration Economics Co., 837 Servel, Inc., 872 H. J. Somers, Inc., 854 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Serve!, Inc., 872 United States Air Conditioning H. J. Somers, Inc., 854 Corp., 810 AIR COMPRESSORS {See Com Spencer Heater Division, 980-981 Unit Heater & Cooler Co., 840 ' pressors, Air) Trane Company. The, 838-839 Universal Cooler Corp., 873 United States Air Conditioning Viiter Manufacturing Co., 876 Corp., 810 ' Westinghouse Electric & Manu AIR CONDITIONING CONp TROLS, {See Controllers. onConlrol Equipment, Humidity Controls) United States Radiator Corp., 982 983 Unit Heater and Cooler Co., 840 Universal Cooler Corp., 873 -, facturing Co., 808-809. 855 L. J. Wing Mfg. Co., 890-891 York Ice Machinery Corp., 811 Young Radiator Company, 841 Viiter Manufacturing Co., 876 Webster Engineering Co., 993 AIR CONDITIONING GRILLES Westinghouse Electric and Manu AIR DIFFUSERS (See Grilles, Registers) AIR CONDITIONING REGIS TERS {See Grilles, Registers) facturing Co.. 808-809, 855 . Williams Oil-O-Matic Heating Cor poration. 820 York Ice Machinery Corp., 811 Young Radiator Company, 841 American Blower Corp., 802-803 Anemostat Corp. of America, 895 Auer Register Co., The. 896 Barber-Colman Co., 897, 913 Hart & Cooley Mfg. Co., 898*899 independent Register Co., 901 AIR CONDITIONING UNITS Airtemp Div. Chrysler Corp., 812- AIR COOLING AND DEHUMIDIFYING APPARATUS Tuttle & Bailey, Inc.. 902-903 United States Register Co., 904 Waterloo Register Co., 905 Aerofin Corporation, 862-864 American Blower Corp., 802-803 Airtemp Div. Chrysler Corp., 812 AIR DUCTS {See Ducts) American Radiator & Standard 813 Sanitary Coro., 962-965 American Blower Corp., 802-803 Autovent Fan & Blower Co., 877 Baker Ice Machine Co., 866 Buffalo Forge Company, 881 Burnham Boiler Corp., 967 American Radiator & Standard Sanitary Corp., 962-965 American Moistening Co., 857 Autovent Fan & Blower Co., 877 AIR ELIMINATORS American Radiator & Standard Sanitary Corp., 962-965 Numerals following Manufacturers' Names refer to pages In the Catalog Data Section 1065 HEATINC VENTILATING AIR CONDITIONING GUIDE, 1940 Armstrong Machine Works, 1002 AIR TUBING, Flexible Metal 1003 ' (See Tubing. Flexible Metallic) C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 AIR VELOCITY METERS (See Illinois Engineering Co., 950-951 Meters, Air Velocity) Mueller Steam Specialty Co., Inc., 1010 . Sarco Company, Inc., 952-953 AIR VELOCITY REGULATORS Trane Company, The, 838-839 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 Johnson Service Co., 922-923 Powers Regulator Co., 930-931 Minneapolis-Honeywell Regulator Co., 926-927 ATTIC FAN COOLERS (See Fans, Attic; Ventilators, Attic) AUTOMATIC FUEL BURNING EQUIPMENT (See Burners, Au tomatic; Coal Burners, Automatic; Furnace Burners; Gas Burners; Oil Burners; Stokers) AUTOMATIC SHUTTERS (See Shutters, Automatic) -' AIR FILTERS (See Filters, Air, also Air Cleaning Equipment) AIR FITTINGS, Brasfc Martocello, Jos. A. & Sons, 861 AIR FILTER CLEANING COM POUNDS Oakite Products, Inc., 856 AIR MEASURING AND RE , CORDING INSTRUMENTS American Blower Corp., 802-803 American Moistening Co., 857 . Babcock & Wilcox Co., 966 Bristol Company, The, 916 Julien P. Frier & Sons, Div. of Bendix Aviation Corp., 917 Grinnell Co., Inc., 944-946, 1007 Illinois Testing Laboratories, Inc., 921 Johnson Service Co., 922-923 Minneapolis-Honeywell -Regulator _ Company, 926-927 Palmer Company, 929 Parks-Cramer Company, 807 Powers Regulator Co., 930-931 Taylor Instrument Companies, 934 935 AIR MOISTENING APPARA TUS (See Humidifiers) AIR WASHERS Air-Mare Corp., 844-845 American Blower Corp., 802-803 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 Baker Ice Machine Co., 866 Bayley Blower Company, 880 Binks Manufacturing Co., 858-859 Buffalo Forge Company, 881 Oarage Fan Company, 805 . Delco Appliance Div., General Motors Sales Corp., 814-815 Henry Furnace & Foundry Co., 822 Meyer Furnace Company, 823 L. J. Mueller Furnace Co., 824-825 Niagara Blower Company. 806 Parks-Cramer Company, 807 H. J. Somers, Inc., 854 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 United States Air Conditioning Corp., 810 Unit Heater and Cooler Co., 840 Vilter Manufacturing Co., 876 York Ice Machinery Corp., 811 ALARMS, Water Level Illinois Engineering Co., 950-951 McDonnell & Miller. 960-961 Mercoid Corporation. 928 Minneapolis-Honeywell Regulator Co., 926-927 Mueller Steam Specialty Co., 1010 Warren Webster & Co., 954-957 Wright-Austin Company, 1011 Yamall-Waring Company, 1012 AUTOMOBILE HEATER FANS Torringlon Mfg. Co., The, 887-889 BACTERIA CONTROL Oakite Products, Inc., 856 BEARING, Bronze Arthur Harris Co., 995 BENDS, Pipe Baker Ice Machine Co., 866 Crane Co., 968-969 Frick Company, 869 General Refrigeration Corp., 870 Grinnell Co.. Inc., 944-946, 1007 Arthur Harris & Co.. 995 . Parks-Cramer Co., 807 Vilter Manufacturing Co., 876 York Ice Machinery Corp., 811 BENDS, Return (See Pipe, Return Bends) BLOCKS, Asbestos Carey, Philip, Co., 1027 Ehret Magnesia Manufacturing Co., 1030-1031 Johns-Manville, 1040-1041 Ruberoid Co., The, 1046-1047 BLOWERS, Fan (See Fans, Supply and'Exhaust) AIR PURIFYING APPARATUS Air-Maze Corp., 844-845 American Air Filter Company, Inc., 846-847 Buffalo Forge Co., 881 Burnham Boiler Corp., 967 Carrier Corporation, 804 Coppus Engineering Corp., 848 Davies Air Filter Corp., 849 Delco Appliance ' Div., General Motors Sales Corp., 814-815 DeBothe:at Div., American Ma chine Metals, Inc., 883 Ilg Electric Ventilating Co., 884 Niagara Blower Company, 806 . Owens-Corning Fiberglas Corp., 850-851 H. J. Somers, Inc., 854 - Staytiew Filter Corp., 852-853 Westinghouse Elec. & Mfg. Co., 808-809, 855 L. J.'Wing Mfg. Co., 890-891 AIR RECEIVERS (See Receivers, Air) ALGAE PREVENTION (See also Slime Prevention) BLOWERS, Forced Draft Oakite Products, Inc., 921 American Blower Corp., 802-803 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 AMMONIA COILS (See Coils, Bayley Blower Company, 880 Ammonia) Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 ANEMOMETERS Clarage Fan Company, 805 Coppus Engineering Corp., 848 Julien P. Friez & Sons, Div. Bendix Aviation Corp., 917 of ' Curtis Refrigerating Machine Co., Div. of Curtis Manufacturing Co., Illinois Testing Laboratories. Inc., 921 . Taylor Instrument Companies, 934 935 ' 868 .w DeBothezat DivisionAmencan Ma chine & Metals, Inc., 883 Henry Furnace & Foundry Co., 822 Se'wel, Inc., 872 ASBESTOS PRODUCTS (See also B. F. Sturtevant Co., 886 Insulation) Westinghouse Elec. & Mfg. Co., OAO OflQ Carey, Philip, Co., 1027 L. J. Wing Mfg. Co.. 890-891 Ehret Magnesia Manufacturing Co., 1030-1031 Johns-Manville, 1040-1041 H. W. Porter & Co., 1015 Ric-wiL Company, The. 1016 Ruberoid Co., The. 1046-1047 United States Gypsum Co., 1049 BLOWERS, Heating and Venti lating American Blower Corp., 802-803 American Coolair Corp.! 878-879 Please mention THE GUIDE 1940 when writing to Advertisers 1066 INDEX TO MODERN EQUIPMENT Autovent Fan &. Blower Co., 877 Bayley Blower Company, 880 Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 Clarage Fan Company, 805. - DeBothezat Division American Ma chine & Metals, Inc., 883 C. A. Dunham Co., 942-943 Fedders Manufacturing Co., 828 Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating Co., 884 F. Jaden Manufacturing Co., 829 Lau Blower Co., 885 McCord Radiator & Mfg. Co., 834 McQuay, Incorporated, 830-831 Meyer Furnace Co., The, 823 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 J. J. Nesbitt, Inc.. 836 B. F. Sturtevant Co., 886 Trane Company, The. 838-839 United States Air Conditioning Corp., 810 Westinghouse Elec. & Mfg. Co., 808-809. 855 Williams Oil-O-Matic Heating Corp., 820 L. J. Wing Mfg. Co., 890-891 BLOWER HOUSINGS Lau Blower Co., 885 Lau Blower Co., 885 Meyer Furnace Company; 823 L. J. Mueller Furnace Company, 824-825 Torrington Mfg. Co., 887-889 Trane Company, The, 838-839 . United States Air Conditioning Corp.. 810 Westinghouse Elec. & Mfg. Co., 808-809, 855 L. J. Wing Mfg. Co., 890-891 BOILER-BURNER Airtemp Div., Chrysler Corp., 812 813 American Radiator & Standard Sanitary Corp., 962-965 Carrier Corporation, 804 Crane Co.. 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 . Gar Wood Industries, Inc., 818-819 General Electric Co., 816-817, 892 893 Henry Furnace &.Foundry Co., 822 Herman Nelson Corp., 835 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. Co., 808-809. 855 Williams Oil-O-Matic Heating Corp., 820 York Ice Machinery Corp., 811 International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 Westinghouse Elec. & Mfg. Co., 808-809 BOILERS, Gas Burning Airtemp Div. Chrysler Corp., 812 813 American Radiator & Standard Sanitary Corp., 962-965 Brownell Company, 985 Burnham Boiler Corp., 967 Crane Company, 968*969 Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Farrar & Trefts, Inc., 972 Fitzgibbons Boiler Co., 970-971 General Electric Company, 816-817, 892-893 International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 L. J. Mueller Furnace Co., 824-825 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 Westinghouse Elec. & Mfg. Co., 808-809, 855 BLOWER MOTORS (See Motors, Electric) BLOWERS, Pressure American Blower Corp., 802-803 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 . Bayley Blower Company, 880 Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 Clarage Fan Company. 805 DeBotheTat Division American Ma chine & Metals, Inc., 883 Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating Co., 884 Lau Blower Co., 885 Martocello, Jos. A. & Co., 861 McCord Radiator & Mfg. Co., 834 B. F. Sturtevant Co., 886 L. J. Wing Mfg. Co., 896-891. BLOWERS, Turbine Coppus Engineering Corp., 848 General Electric Co., 816-817, 892 893 B. F. Sturtevant Co., 886 L. J. Wing M*g. Co.. 890-891 BLOWERS, Warm Air Furnace American Blower Corp., 802-803 American Coolair Corp., 878-879 American Radiator & Standard Sanitary Corp.. 962-9165 Autovent Fan & Blower Co.. 877 Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 Clarage Fan Company. 805 DeBothezat Division American Ma chine & Metals, Inc., 883 General Electric Co., 816-817, 892 893 Henry Furnace & Foundry Com pany, 822 F. Jaden Manufacturing Co., 829 BOILER COMPOUNDS (See Com BOILERS, Heating pounds, Boiler) '. American Radiator & Standard BOILER COVERING (See Cover ing, Pipes and Surfaces) Sanitary Corp., 962-965 Brownell Company, 985. Burnham Boiler Corp., 967 . Crane Company, 968-969 . BOILER FEED PUMPS Pumps, Boiler Feed) (See Delco Appliance Div., General Motors Sales Corp., 814-815 Farrar & Trefts. Inc., 972 Fitzgibbons Boiler Co., 970-971 BOILER FEEDERS (See Feeders, Gar Wood Industries, 818-819 General Electric Company, 816 Boiler) 817, 892-893 Henry Furnace & Foundry Co., 822 BOILER Boiler) TUBES .. (See Tubes, International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 L. J. Mueller Furnace Co., 824-825 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 BOILER WATER TREATMENT Smith Twin Tubular Boiler Co., 979 Cochrane Corp., 1005 Vinco Company, Inc., 958-959 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 Weil McLain Company, 984 BOILERS, Cast-Iron Westinghouse Elec. & Mfg. Co., 808-809. 855 American Radiator & Standard Sanitary Corp., 962-965 Burnham Boiler Corp., 967 BOILERS, Magazine Feed Crane Co., 968-969 * Delco Appliance Div., General Burnham Boiler Corp., 967 Motors Sales Corp., 814-815 Spencer Heater Division. 980-981 L. J. Mueller Furnace Co., 824-825 -Weil-McLain Company, 984 Spencer Heater Division, 980-981 - United States Radiator Corp., 982 983 . BOILERS, Oil Burning Weil-McLain Company, 984 Westinghouse Elec. & Mfg. Co., Airtemp Div. Chrysler Corp., 812 808-809, 855 813 American Radiator & Standard Sanitary Corp., 962-965 BOILERS, Down Draft Babcock &Wilcox Co., 966 Brownell Company, The, 985 Brownell Company, 985 Burnham Boiler Corp., 967 Farrar & Trefts, 972 ' Crane Company, 968-969 Fitzgibbons Boiler Co., 970-971 Delco Appliance Div., General Gar Wood Industries, Inc., 818-819 Motors Sales Corp., 814-815 Henry Furnace & Foundry Co., 822 Farrar &' Trefts, Inc., 972 Numerals following Manufacturers' Names refer to pages in the Catalog Data Section 1067 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Fitzgibbons Boiler Co., 970-971 Gar Wood Industries, Inc., 818-819 General Electric Company, 816-817, 892-893 International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 L. J. Mueller Furnace Co., 824-825 . Herman Nelson Corp., 835 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 Smith Twin Tubular Boiler Co., 979 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 Weil-McLain Company, 984 Westinghouse Elec. & Mfg. Co., 808-809 BURNERS; Coal (See Coal Bur ners) BURNERS, Combination Gas and Oil Todd Combustion Equipment, Inc., 994 BURNERS. Gas (See Gas Burners) BURNERS, Oil (See Oil Burners) CALKING, Building BOILERS. Steel Babcock & Wilcox Co., 966 Brownell Company, The, 985 Burnham Boiler Corp., 967 Combustion Engineering Co., 988 Farrar & Trefts, Inc., 972 Fitzgibbons Boiler Co., 970-971 Frick Company, 869 Gar Wood Industries, 818-819 International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 Smith Twin Tubular Boiler Co., 979 Spencer Heater Division, 080-981 Chamberlin Metal Weather Strip Co., 1018-1019 CASTINGS, Bronze and Dairy Metal Arthur Harris & Co., 995 CEMENT, Asbestos Carey, Philip. Co., 1027 Eagle-Picher Lead Co., 1032 Ehret Magnesia Manufacturing Co., 1030-1031 Johns-Manville, 1040-1041 Ruberoid Co., The, 1046-1047 BOILERS. Water Tube CEMENT, Refractory (See Re Babcock & Wilcox Co., 966 Burnham Boiler Corp., 967 fractories) Combustion Engineering Co., 988 Fit*gibbons Boiler Co., 970-971 CEMENT, Rock Wool Frick Company, 869 International Boiler Works Co.. 973 Smith Twin Tubular Boiler Co., 979 Spencer Heater Division,' 980-981 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 Ehret Magnesia Manufacturing Co., 1030-1031 General Insulating & Mfg. Co., 1033 BREECHINGS AND Johns-Manville, 1040-1041 Ruberoid Co., The. 1046-1047 CHIMNEYS -Standard Lime & Stone Co., 1048 COAL BURNERS, Automatic, Bituminous Brownell Company, 985 Crane Company, 968-969 Combustion Engineering Co., 988 Delco Appliance Div., General Motors Sales Corp., 814-815 Detroit Stoker Company, 86-987 Henry Furnace & Foundry CoT, 822 Iron Fireman Mfg. Co., 990-991" Meyer Furnace Company, 823, Pocahontas Fuel Co., 826 Spencer Heater Division, 980-981 COILS, Aluminum Aerofin Corporation, 862-864 Baker Ice Machine Co., Inc., 866 Delco Appliance Div., General Motors Sales Corp., 814-815 Arthur Harris & Co., 995 McQuay Incorporated, 830-831 J. J. Nesbitt, Inc., 836 Niagara Blower Company, 806 Refrigeration Economics Co., 837 B. F. Sturtevant Co.. 886 Trane Company, The, 838-839 Unit Heater and Cooler Co., 840 Young Radiator Company, 841 COILS, Ammonia Aerofin Corporation, 862-864 Baker Ice Machine Co.. 866 Carrier Corporation, 804- Crane Company, 968-969 Frick Company, 869 - G & O Manufacturing Co., 865 General Refrigeration Corp., 870 McQuay, Incorporated, 830-831 Refrigeration Economics Co., 837 Trane Company, The. 838-839 Unit Heater and Cooler Co., 840 Vilter Manufacturing Co., 876 Worthington Pump & Machinery Corp., 874-875 Yarnall-Waring Co., 1012 York Ice Machinery Corp., 811 Young Radiator Company, 841 Bethlehem Steel Co., 908 Farrar & Trefts, 972 International Boiler Works Co., 973 BURNERS, Automatic (5ee also Coal Burners, Stokers) ` Airterap Div., Chrylser Corp., 812 813 American Radiator & Standard Sanitary Corp., 962-965 Crane Company, 968-969 Combustion Engineering Co., 988 Delco Appliance Div., General Motors Sales Corp., 814-815 ' Detroit Stoker Company, 986-987 Gar Wood Industries, Inc., 818-819 General Electric Company, 816-817, 892-893 Iron Fireman Mfg. Co., 990-991 MotorStoker Div., Hershey Ma chine & Fdy. Co., 989 Herman Nelson Corp., 835 Pocahontas Fuel Co., 826 Spencer Heater Division, 980-981 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. Co.. 808-809, 855 Williams Oil-O-Matic .Heating Corp., 820 CHAIN PULLEYS (See Pulleys, Chain) CIRCULATORS, Hot Water Heating Bell and Gossett Co., 941 Crane Company, 968-969 General Electric Company, 816-817, 892-893 Westinghouse Elec. & Mfg. Co., 808-809. 855 CLEANERS, Air (See Air Cleaning Equipment) COAL BURNERS, Automatic, Anthracite Buffalo Forge Company, 881 . Crane Company, 968-969 Combustion Engineering Co., 988 Henry Furnace & Foundry Co., 822 Iron Fireman Mfg. Co., 990-991 MotorStoker Div., Hershey Ma chine & Fdy. Co.. 989 Spencer Heater Division, 980-981 COILS, Brass Aerofin Corporation, 862-864 E. B. Badger & Sons Co.. 1004,1017 Carrier Corporation. 804 . Crane Company, 968-969 Grinnell Co., Inc., 944-946, 1007 Arthur Harris & Co., 995 B. F. Sturtevant Co., 886 COILS, Pipe, Cppper . Aerofin Corporation, 862-864 American Radiator & Standard Sanitary Corp., 962-965 E. B. Badger & Son Co., 1004, 1017 Baker Ice Machine Co., Inc., 866 Bell and Gossett Co., 941 Crane Company. 968-969 Curtis Refrigerating Machine Co., Division of Curtis Manufacturing Co., 868 Fedders Manufacturing Co., 828 Frick Company, 869 Grinnell Co.. Inc., 944-946, 1007 Arthur Harris & Co., 995 Kewanee Boiler Corp., 974-977 McQuay, Incorporated, 830-831 J. J. Nesbitt. Inc., 836 Niagara Blower Company, 806 Refrigeration Economics Cd., 837 Please mentic n THE GUIDE 1940 when writing to Advertisers ' INDEX TO MODERN EQUIPMENT Serve!, Inc., 872 ` Westinghouse Elec. & Mfg. Co., 808-809 . York Ice Machinery Corp., 811 Young Radiator Company, 841 COILS, Pipe, Iron Bayley Blower Company, 880 Clarage Fan Company, 805 Crane Company, 968-969 ` Frick Company; 869 General Refrigeration Corp., 870 Grinnell Co., Inc., 944-946,' 1007 Arthur Harris & Co., 995 Refrigeration Economics Co., 837 . Vilter Manufacturing Co., 876 Worthington Pump & Machinery Co.. 874-875 York Ice Machinery Corp., 811 COILS, Stainless Steel Arthur Harris & Co., 995 COILS, Tank r American District Steam Co., 1000, 1014 . American Radiator & Standard Sanitary Corp., 962-965 Baker Ice Machine Co., 866 Bell and Gossett Co., 941 CLaraga Fan Company, 805 Crane Company, 968-969 Frick Company, 869 Arthur Harris & Co., 995 Kewanee Boiler Corp., 974-977 McQuay, Incorporated, 830-831 Refrigeration Economics Cot, 837 Unit Heater & Cooler Co., 840 Vilter Manufacturing Co., 876 York Ice Machinery Corp., 811 COLUMNS, Water . Brownell Company, 985 Crane Company, 968-969 Detroit Lubricator Co., 914-915 Kieley & Mueller, Inc., 1009 ' Mueller Steam Specialty Co., 1010 Wright-Austin Company, 1011 Yarnall-Waring Company, .1012 COMBUSTION CHAMBERS Babcock & Wilcox Co., 966' . Combustion Engineering Co., 988 COMPOUNDS, Asphalt, for Conduits Ruberoid Co., 1046-1047 COMPOUNDS, Boiler Vinco Co., Inc., 958-959 COMPOUNDS, Boiler and Radi ator Sealing Dole Valve Company, 1006 Vinco Co., Inc., 958-959 COMPOUNDS, Cleaning Oakite Products, Inc., 856 Vinco Co., lnc.i 958-959 COMPOUNDS, Soot Destroyer Vinco Co., Inc., 958-959 COMPRESSORS, Air Baker Ice Machine Co., 866 Binks Manufacturing Co., 858-859 Brunner Manufacturing Co., 867 Curtis Refrigerating Machine Co., Division of Curtis Manufacturing Company, 868 . General Electric Company, 816-817, 892-893 . Nash Engineering Co., 998-999 B. F. Sturtevant Co., 886 . Worthington Pump and Machinery Corp., 874-875 COMPRESSOR MOTORS (See Motors, Electric) COMPRESSORS, Refrigeration Airtemp Div., Chrysler Corp., 812 813 Baker Ice Machine Co., 866 Brunner Manufacturing Co., 867 Carbondale Div., Worthington Pump & Machinery Corp.. 874 875 Carrier Corporation, 804 Curtis Refrigerating Machine Co., Division Curtis Manufacturing Co.. 868 Delco Appliance Div., General Motors Sales Corp., 814-815 Fitzgibbons Boiler Co., 970-971 Frick Company, 869 General Electric Company, 816-817, 892-893 General Refrigeration Corp., 870 Servel, Inc., 872 Trane Company, The, 838-839 Universal Cooler Corp., 873 Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co., 808-809, 855 Williams Oil-O-Matic Heating Corp., 820 York Ice Machinery Corp., 811 COMPRESSOR TUBING, Flex ible (See Tubing, Flexible Metal . He) CONDENSERS Aerofin Corporation, 862-864 Airtemp Div., Chrysler Corp., 812 813 Baker Ice Machine Co., 866 Brunner Manufacturing Co., 867 Carbondale Division Worthington . Pump & Machinery Corp., 874 875 Carrier Corporation. 804 Curtis Refrigerating Machine-Co., 868Div. Curtis Manufacturing Co., Fedders Manufacturing Co., 828 Frick Company, 869' G & O Manufacturing Co., 865 General Electric Company, 816-817, 892-893 General Refrigeration Corp., 870 Mario Coil Company, 871 McQuay, Incorporated, 830-831 Modine Mfg. Co.. 832-833 Niagara Blower Company, 806 Refrigeration Economics Co., 837 Servel, Inc., 872 ' B. F. Sturtevant Co., 886 Trane Company, 838-839 Unit Heater and Cooler Co., 840 Universal Cooler Corp., 873 Vilter Manufacturing Go'., 876 Westinghouse Elec. & Mfg. Co., 808-809; 855 York Ice Machinery Corp., 811 Young Radiator Company, 841 CONDENSER CLEANER Oakite Products, Inc, 856 CONDUIT, Flexible Mettallc Trane Company, 838-839 CONDUITS, Underground Flt, tings American District Steam Company, 1000. 1014 General Electric Company. 816-817, 892-893 H. W. Porter & Co., 1015 Ric-wiL Company, The, 1016 Underground Steam Construction Co., 1017 CONDUITS, Underground Pipe American District Steam Company, 1000. 1014 Carey, Philip, Co., 1027 Ehret Magnesia Manufacturing Co., 1030-1031 ' Johns-Manville, 1040-1041 Jones & Laughlin Steel Corp., 910 H. W. Porter & Co., 1015 Ric-wiL Company, The, 1016 Underground Steam Construction Co.. 1017 CONNECTIONS, Flexible Charging Henry Valve Company, 920 ' CONTROL, Air Volume Damper Anemostat Corp. of America, 895 Auer Register Co., The, 896 Barber-Colman Co., 897, 913 Fulton Sylphon Co., 918-919 Hart & Cooley Mfg. Co., 898-899 Illinois Engineering Co., 950-951 Independent Register Co., 901 Johnson Service Co., 922-923 Minneapolis-Honeywell Regulator Co., 926-927 Tuttle & Bailey, Inc., 902-903 . Waterloo Register Co., 905 ' CONTROL EQUIPMENT, Combustion Barber Gas Burner Co., 992 Bristol Company, The, 916 Detroit Lubricator Co., 914-915 Fulton Sylphon Co., 918-919 Leeds & Northrup Co., 924 McDonnell & Miller, 960-961 ' Mercoid Corporation, 928 ' Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switch Co., 932 ' Numerals following acturers' Names refer to pages ii the Catalog Data Section HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Spence Engineering Co.. 933 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. 808-809. 855 White-Rodgers Elec. Co., 937 L. J. Wing Mfg. Co., 890-891 Co.. Champion BlowerTk Forge Co., 882 Clarage Fan Company, 805 Curtis Refrigerating Machine Co., Div. of Curtis Manufacturing Co., 868 ; DeBothezat Division. American Machine & Metals, Inc., 883 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Unit Heater and Cooler Co., 840 Universal Cooler Corp., 873 Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co., 808809, 855 C. A. Dunham Co.. 942-943 Yarnall-Waring Co., 1012 CONTROLLERS AND CON TROL EQUIPMENT (See also Humidity and Temperature Con trol) . Fedders Manufacturing Co., 828 Fitzgibbons Boiler Co., 970-971 Frick Company, 869 G & O Manufacturing Co., 865 General Electric Company, 816-817, York Ice Machinery Corp., 811 Young Radiator Company, 84^ COOLING TOWERS, Atmos- American Radiator & Standard 892-893 Sanitary Corp., 962-965 General Refrigeration Corp., 870 Barber-Colman Co., 897. 913 . Henry Furnace & Foundry Co., 822 Barber Gas Burner Co., 992 Ilg Electric Ventilating Co., 884 Bristol Company, The, 916 . F. Jaden Manufacturing Co., 829 Detroit Lubricator Co., 914-915 Lau Blower Co., 885 C. A. Dunham Co., 942-943 Mario Coil Company, 871 Julien P. Friez & Sons, Div. of McQuay, Incorporated, 830-831 Bendix Aviation Corp., 917 Meyer Furnace Co., 823 Fulton Sylphon Co., 918-919 Modine Mfg. Co., 832-833 Hoffman Specialty Co., Inc., 948 J. J. Nesbitt, Inc., 836 949 ' Herman Nelson Corp., 835 Illinois Engineering Co., 950-951 Niagara Blower Company, 806 Illinois Testing Laboratories, Inc., Refrigeration Economics Co., 837 herlc. Mechanical Draft, orced Draft, Induced Draft (See also Cooling Equipment, Water) . American Blower Corp., 802-803 Baker Ice Machine Co., 866 Binks Manufacturing Co., 858859 Buffalo Forge Company, 881 Marley Company, 860 Mario Coil Company, 871 McQuay, Incorporated, 830-831 Unit Heater & Cooler Co., 840 York Ice Machinery Corp., 811 921 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 Leeds & Northrup Co., 924 Manning, Maxwell & Moore, Inc., 925 Minneapolis-Honeywell Regulator Co., 926-927 Parks-Cramer Company, 807 Serve!, Inc., 872 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Unit Heater and Cooler Co., 840 United States Air Conditioning Corp., 810 ' Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co., 808-809,855 . CORROSION, Treatment of Oakite Products, Inc., 856 Vinco Company, Inc.. 958959 COVERING, Pipe Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 . Taylor Instrument Companies, 934- Williams Oil-O-Matic Heating Corporation. 820 ' L. J. Wing Mfg. Co., 890-891 York Ice Machinery Corp., 811 Young Radiator. Company, 841 American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Baker Ice Machine Co., 866 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 . Ehret Magnesia Mfg. Co., 1030 Warren Webster & Co., 954-957 1031 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. Co., . 808-809. 855 White-Rodgers Elec. Co., 937 Young Radiator Co., 841 COOLING EQUIPMENT, Oil Grinnell Co., Inc., 944-946, 1007 General Insulating & Mfg. Co., 1033 Aerofin Corporation, 862-864 Hinde & Dauch Paper Co., 1034 Carbondale Div. Worthington 1035 . Pump & Machinery Co., 874-875 Insulation Industries. Inc., 1038 Frick Company, 869 . Johns-Manville, 1040-1041 . G & O Manufacturing Co., 865 Mundet Cork Corp., 1044 CONVECTION HEATERS - Niagara Blower Company, 806 4 Servel, Inc., 872 Owens-Corning Fiberglas Corp., 850-851 American Radiator & Standard Unit Heater and Cooler Co., 840 Pacific Lumber Co., 1045 Sanitary Corp., 962-965 Crane Company, 968-969 C. A. Dunham Co., 942-943 Universal Cooler Corp., 873 York Ice Machinery Corp., 811 Young Radiator Company, 841 H.-W._ Porter & Co., 1015 Ric-wiL Company, The, 1016 Ruberoid Co., The. 1046-1047 Grinnell Co., Inc., 944-946, 1007 Standard Lime & Stone Co., 1048 McCord Radiator & Mfg. Co., 834 United States Gypsum Co., 1049 McQuay, Incorporated, 830-831 COOLING EQUIPMENT, Water Modine Mfg. Co., 832-833 . (See also Water Cooling) John J. Nesbitt, Inc., 836 ' Trane Company, The, 838-839 ' United States Air Conditioning Corp., 810 United States Radiator Corp., 982 983 Warren Webster & Co., 954-957 Weil-McLain Company, 984 Young Radiator Co., 841 Aerofin Corporation, 862-864 Airtemp Div., Chryiser Corp., 812 813 American Blower Corp., 802-803 Baker Ice Machine Co., 866 . Binks Manufacturing Co., 859 Buffalo Forge Company, 881 Carbondale Div. Worthington Pump & Machinery Corp., 874 875 COVERING, Surfaces American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Baker Ice Machine Co., 866 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030 1031 ___ General Insulating & Mfg. Co., 1033 Hinde & Dauch Paper Co., 1034- COOLING EQUIPMENT. Air 828 I Station Industrie,. Inc.. 1038 ^ Aerofin Corporation, 862-864 Airtemp Div., Chrysler Corp., 812- 813 American Blower Corp., 802-803 Autovent Fan & Blower Co., 877 Baker Ice Machine Co., Inc., 866 Binks Manufacturing Co., 858-859 Buffalo Forge Company, 881 . Carbondale Division Worthington Pump & Machinery Co., 874-875 Carrier Corporation, 804 Frick Company, 869 International Fibre Board, Ltd., General Refrigeration Corp., 870 1039 F. Jaden Manufacturing Co., 829 ` Johns-Manville, 1040-1041 Marley Co., The, 860 Mundet Cork Corp., 1044 McCord Radiator & Mfg. Co., 834 Owens-Corning Fiberglas Corp., McQuay, Incorporated, 830-831 850-851 Modine Manufacturing Co., 832- Pacific Lumber Co., The, 1045 -833 Ruberoid Co., The, 1046-1047 J. J. Nesbitt, Inc., 836 Standard Lime & Stone Co., 1048 Niagara Blower Company, 806 Western Felt Works, 1050 Refrigeration Economics Co., 837 York Ice Machinery Corp., 811 Please mention THE GUIDE 1940 when writing to Advertisers . .INDEX TO MODERN EQUIPMENT CUT-OFFS, Low Water DAMPERS, Mechanical DOOR BOTTOM SEALS Detroit Lubricator Co., 914-915 McDonnell & Miller, 960-961 Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switeh Co., 932 DAMPER REGULATORS, Boiler (See also Regulators) American Radiator & Standard ` Sanitary Corp., 962-965 Barber-Colman Co., 897, 913 Buffalo Forge Company, 881 Clarage Fan Company, 805 Fulton Sylphon Co., 918-919 Hart & Cooley Mfg. Co., 898-899 Henry Furnace & Foundry Co., 822 Johnson Service Co., 922-923 Minneapolis-Honeywell Regulator Co., 926-927 Powers Regulator Co., 930-931 United States Register Co., 904 Chamberlin Metal Weather Strip Co.. 1018-1019 DRAFT APPARATUS (See Blow ers, Forced Draft) DRYERS, Refrigerant Henry Valve Company, 920 Barber-Colman Co., 897, 913 Barnes & Jones, Inc., 940 ' Detroit Lubricator Co., 914-915 C. A. Dunham Co., 942-943 DAMPERS, Back Draft (See DRYING EQUIPMENT ' Dampers, Air Volume Control) American Blower Corp., 802-803 Fulton Sylphon Co., 918-919 American Coolair Corp., 878-879 Hart & Cooley Mfg. Co., 898-899 Henry Furnace & Foundry Co., 822 DEHUMIDIFIERS American Radiator & Standard Sanitary Corp., 962-965 Hoffman Specialty Co., Inc., 948 949 . Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 Leeds & Northrup Co., 924 Minneapolis-Honeywell Regulator Co.. 926-927 Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 Taylor Instrument Companies, 934 935 Trane Company, The, 838-839 Warren Webster & Co., 954-957 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. Co., 808-809, 855 Aerofin Corporation, 862-864 Airtemp Div. Chrysler Corp., 812 813 American Blower Corp., 802-803 Buffalo Forge Company, 881 Carrier Corporation, 804 Clarage Fan Company, 871 General Refrigeration Corp., 870 Grinnell Co., Inc., 944-946. 1007 McQuay, Incorporated, 830-831 J. J. Nesbitt, Inc., 836 Parks-Cramer Co., 807 ' Refrigeration Economics Co.. 837 H. J. Somers, Inc., 854' Trane Company, The, 838-839 United States Air Conditioning Corp., 810 Westinghouse Elec. & Mfg. Co.. Autovent Fan & Blower Co., 877 Buffalo Forge Company. 881 Carrier Corporation, 804 Champion Blower & Forge Co., 882 Clarage Fan Company, 805 Delco Appliance Div., General Motors Sales Corp., 814-815 G & O Manufacturing Co., The, 865 Ilg Electric Ventilating Co., 884 McQuay. Incorporated, 830-831 Refrigeration Economics Co., 837 B. F. Sturtevant Co., 886 Trane Company, The. 838-839 Unit Heater and Cooler Co., 840 L. J. Wing Mfg. Co., 890-891 Worthington Pump & Machinery Co., 874-875 York Ice Machinery Corp., 811 808-809.855 PAMPER REGULATORS. Furnace Worthington Pump & Machinery Co., 874-875 DUCT INSULATION (See Insu- York Ice Machinery Corp., 811 lotion. Duct) Barber-Colman Co., 897, 913 Detroit Lubricator Co., 914-915 Julien P. Frie2 & Sons, Div. of DEHYDRATORS, Refrigerant Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 Henry Valve Co., 920 Hart & Cooley Mfg. Co., 898-899 Henry Furnace & Foundry Co., 822 Kieley & Mueller, Inc., 1009 Leeds & Northrup Co., 924 DEHYDRA-TECTORS, Refrigerant Manning, Maxwell & Moore, Inc.. 925 Henry Valve Company, 920 Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switch Co., 932 DEHYDRANTS Powers Regulator Co., 930-931 Sarco Company, Inc.r 952-953 Henry Valve Company, 920 Spence Engineering Co., 933 Tuttle & Bailey, Inc., 902-903 United States Register Co., 904 DEODORANTS Webster Engineering Co., 993 Oakite Products, Inc., 856 DUCTS, Prefabricated (See also Fittings, Air Ducts, Furnace) Carey, Philip, Co., 1027 DUST COLLECTING EQUIPMENT American Air Filter Co., 846-847 Buffalo Forge Company. 881 Clarage Fan Company, 805 Davies Air Filter Corp., 849 Owens-Corning Fiberglas Corp., 850-851 Staynew Filter Corp., 852-853 B. F. Sturtevant Co., 886 ' Unit Heater & Cooler Co., 840 Westinghouse Elec. & Mfg. Co.. 808-809, 855 DAMPERS, Air Volume Control Anemostat Corp. of America, 895 Auer Register Co., The, 896 Barber-Colman Co., 897; 913 Champion Blower & Forge Co., 882 Hart & Cooley Mfg. Co., 898-899 Hendrick Mfg. Co., 900 Independent Register Co., 901 Johnson Service Company, 922-923 Minneapolis-Honeywell Regulator Co., 926-927 Tuttle & Bailey, Inc., 902-903 Waterloo Register Co., 905 DESTROYERS, Soot (See Soot DUST COLLECTORS, Cloth Destroyer) Type American Air Filter Co., 846-847 DIFFUSERS, Air (See fusers, and Ventilators, Wall) Air Dif Floor and American Blower Corp., 802-803 Davies Air Filter Corp., 849 Staynew Filter Corp., 852-853 DISTRICT HEATING (See also Corrosion Treatment of--Expan sion Joints--Insulation, Under ground--Meiers, Pipe) ELECTROSTATIC AIR CLEANERS Westinghouse Elec. & Mfg. Co., 855 DAMPERS, Flue Henry Furnace & Foundry Co., 822 Tuttle & Bailey, Inc., 902-903 American District Steam Co., 1000. 1014 . H. W. Porter & Co., 1015 Ric-wiL Company, The, 1016' ENGINES, Diesel Worthington Pump & Machinery Co., 874-875 Numerals following Manufacturers' Names refer to pages in the Catalog Data Section 1071 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 EVAPORATORS L. J. Mueller Furnace Co.. 824-825 Henry Furnace & Foundry Co., 822 Aerofln Corporation, 862-864 John J. Nesbitt, Inc.. 836 Niagara Blower Company, 806 Lau Blower Co., 885 ''"Meyer Furnace Co., The, 823 Airtemp Div., Chrysler Corp., 812- g p Sturtevant Co., 886 L. J. Mueller Furnace Co., 824-825 813 Torrington Mfg. Co., 887-889 Baker Ice Machine Co., Inc., 866 Trane Company, The, 838-839 Torrington Mfg. Co., 887-889 Trane Company, The, 838-839 Buffalo Forge Co., 881 United States Air Conditioning United States Air Conditioning Carbondale Div. Worthington Corp., 810 Corp., 810 Pump & Machinery Corp., 874- Wagner Electric Corp., 894 Westinghouse Elec. & Mfg. Co., Ca--8r7r5ier rC*o--r--p--o--r-a*t.ion, v8n0A4 . . Curtis Refrigerating Machine Co., Div. Curtis Manufacturing Co., We8--s0--t8-in---8g--0h--9ouse Elec. & Mfg. Co., L. J. Wing Mfg. Co., 890-891 L 8j08W-80in9g Mfg Co> 890-891 . r<r 868 'Fedders Manufacturing Co., 828 FAN BLADES FAN MOTORS (See Motors, Elec tric) *" Frick Company. 869 General Refrigeration Ccoorrpp., 87v0u American Bmlower Cv-orp., 8o0u2*--o8u0o3 Gr-e__n__e_r_aIl PEIl_e__crtr'_ic___C__o__m__p__a__n_y. 816-817, American Coolair Corp., 878-879 FANS, Portable 892-893 Mario Coil Company, 871 McQuay. Incorporated, 830-831 J. J. Nesbitt, Inc., 836 Refrigeration Economics Co.. 837 Serve!, Inc., 872 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Unit Heater & Cooler Co., 840 Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co., 808-809. 855 York Ice Machinery Corp., 811 Young Radiator Company. 841 ' cvuiTier urine /c,. Reads* HEADS P Buffalo Ffrorge Coommppaannyy,_, 881 Champion Blower & Forge C^ o., 882 rCila'irnag^e Fan fCcommnpaannvy, 805 DeBothezatDivision American Ma chine & Metals, Inc., 883 Servel. Inc., 872 Torrington Mfg. Co., 887-889 Westinghouse Elec. & Mfg. Co. 808-809 L. J. Wing Mfg. Co., 890-891 FANS, Centrifugal American Blower Corp., 802-803 American Coolair Corp., 878-879 Anuutiovv*etinut Fraaun &. Blower C--vo., w8.77 BBaavylleevy BBlloowweerr CCoommppaannyy., 888800 Buffalo Forge Company, 881 /C*.hI am- - pi1on-- BK flIoakwhe.*r &9. Forgel*C'Ao.. 882 American Blower Corp., 802-803 American Coolair CCoorrDp.., 87788--887719 Autovent Fan & Blower Co.,- 877 Bayley Blower Company, 880 Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 Coppus Engineering Corp., 848 DeBothezat Division, American Machine & Metals, Inc., 883 General Electric Company, 816-817, 892-893 Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating Co., 884 Lau Blower Company, 885 Torrington Mfg. Co., 887-889 Wagner Electric Corp., 894 Westinghouse Elec. & Mfg. Co., 808-809 l J. Wing Mfg. Co., 890-891 EXHAUST tubing. Flexible ` (See Tubing. Flexible'Metallic) EXPANSION JOINTS C^ilaairdasgce Fraaun C^/UoImUIWpaUnJ1y. 8w0wSv General Electric Company, 816-817 892-893 J_ Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating^Co., 884 FF.."j", den M, ea_'uu.-ffa_ c.^.r. iug''fCxAo.:8OOMA FANS, Propeller onn Amencan Blower Corp., 802-803 AAMmA MelAriiWc.aMn C"Ao>.oTnla| ,ir Corp., 878_-R87790 American District Steam Co.. 1000, Lau Blower Co., 885 1014 Meyer Furnace Company, 823 Autovent Fan & Blower Co., 877 Buffalo Forge Company, 881 E. B. Badger & Sons Co., 1004,1017 Niagara Blower Company. 806 Champion Blower & Forge Co., 882 Baker ice Machine Co.. 866 Crane Company, 968-969 B. F. Sturtevant Co., 886 Torrington Mfg. Co., 887-889 Clarage Fan Company, 805 Coppus Engineering Corp., 848 Fulton Sylphon Co.. 918-919 Grinnell Co., Inc., 944-946, 1007 Arthur Harris & Co., 995 Illinois Engineering Co., 950-951 . Ric-wiL Company, 1016 . Underground Steam Construction TArIadUneC CVoUmIUppadnUy,JTahuew,, 8u3w8-8w3w9v United States Air ConJd-i*ti-o- ning Corp., 810 L. J. Wing Mfg. Co.. 890-891 DeBothezat Division American Machine & Metals, Inc., 883 General Electric Company, 816-817, 892-893 Henry Furnace & Foundry Co., 822 ---Ilg.Electric Ventilating Co., 884 Co.. 1017 FANS. Electric . 885 Warren Webster & Co., 954-957 YarnalFWaring Co.. 1012- . Airtherm Manufacturing Co., 827 Servel, Inc., 872 American Coolair Corp., 878-879 B. F. Sturtevant Co., 886. Autovent Fan & Blower Co., 877 Torrington Mfg. Co., 887-889 EXPOSITIONS Buffalo Forge Company, 881 Trane Company, The, 838-839 _ Champion Blower & Forge Co., 882 United States Air Conditioning ' International Exposition Co., 842 Clarage Fan Company, 805 Coppus Engineering Corp., 848 Corp., 810 ' Westinghouse Elec. & Mfg. Co., DeBothezat Division, American 808-809 FANS, Attic Machine & Metals, Inc., 883 L. J. Wing Mfg. Co.. 890-891 General Electric Company, 816-817, Airtherm Manufacturing Co., 827 892-893 ,,, American Blower Corp., 802-803 Henry Furnace & Foundry Co., 822 American Coolair Corp., 878-879 ' Torrington Mfg. Co., 887-889 Autovent Fan & Blower Co., 877 Wagner Electric Corp., 894 Bayley Blower Company, 880 Buffalo Forge Company, 881 Burnham Boiler Corp., 967 ' Westinghouse Elec. & Mfg. Co.. L.QBJUn.OftW-*8O0iU*n93g Mf-g. C---o.. 8---9---0-*8**9' 1- Champion Blower & Forge Co., 882 Clarage Fan Company, 805 DeBothezatDivision American Ma- FANS, Furnace chine & Metals, Iric., 883 General Electric Company, 816-817. American Blower Corp.. 802-803 ' 892-893 Autovent Fan & Blower Co., 77. Henry Furnace & Foundry Co., 822 Buffalo Forge Company, 881 ' Ilg Electric Ventilating Co., 884 Champion Blower & Forge Co., 882 F. Jaden Manufacturing Co.. 829 Clarage Fan Company, 805 # Lau Blower Co.. 885 DeBothezat Division, American Meyer Furnace Company, 823 Machine & Metals, Inc., 883 FANS, Supply and Exhaust . . _ QO_ Airtherm Manufacturing Co., 827 Amencan Blower Corp., 802-803 A/lLmllCenIlMcaUnI Coo1lAaUir CVVorIpjr., W87f W8--oW7f V AA~m~~ .emrimca. mn Radiat.o..r S&t CSlotannHddard Sanitary Corp., 962-965 Autovent Fan & Blower Co., 877 Bayley Blower Company, 880 . Buffalo Forge Company, 881 Champion Blower & Forge Co., 882 Clarage Fan Company, 805 DeBothezat Division American Machine & Metals, Inc., 883 General Electric Company, 816-817, 892-893 - Henry Furnace & Foundry Co., 822 Please mention THE GUIDE 1940 when writing to Advertisers 1072 INDEX TO MODERN EQUIPMENT Ilg Electric Ventilating Co., 884 ' Lau Blower Co., 885 Meyer Furnace Company, 823 L. J. Mueller Furnace Co., 824-825 FITTINGS, Air Ducts, Furnace Carey, Philip, Co.. 1027 United States Register Co., 1075 FORCED DRAFT COOLING TOWERS (See also Cooling alS,al!)ndUUd Dro/* M`chant- Niagara Blower Company, 806 H. J. Somers, Inc., 854 B. F. Sturtevant Co., 886 Torrington Mfg. Co., 887-889 Trane Company, The, 838-839 United States Air Conditioning Corp., 810 , Wagner Electric Corp., 894 FITTINGS, Pipe, Flanged American Rolling MillCo., 907 Baker Ice Machine Co., 866 Carnegie-Illinois Steel Corp., 909 Crane Company, 968-969 Baker Ice Machine Co., 866 Binks Manufacturing Co., 858-859 Buffalo Forge Company. 881 Marley Company, 860 Unit Heater & Cooler Co., 840 York Ice Machinery Corp., 811 Westinghouse Elec. & Mfg. Co., Dole Valve Company, 1006 808-809 L. J. Wing Mfg. Co., 890-891 Frick Company. 869 Grinnell Co., Inc.. 944-946, 1007 FURNACE-BURNER Arthur Harris & Co., 995 Airtemp Div., Chrysler Corp., 812 Henry Valve Company, 920 813 FEED WATER HEATERS (See United States Register Co., 904 Heaters, Feed Water) Vilter Manufacturing Co., 876 American Radiator & Standard Sanitary Corp., 962-965 Worthington Pump & Machinery Crane Company, 968-969 Co., 874-875 Delco Appliance Div., General FEED WATER REGULATORS York Ice Machinery Corp., 811 (See Regulators, Feed Water) Motors Sales Corp., 814-815 Gar Wood Industries, Inc., 818-819 General Electric Company, 816-817, FITTINGS, Pipe, Screwed 892-893 FEEDERS, Boiler Crane Company, 968-969 Kieley & Mueller, Inc., 1009 McDonnell & Miller. 960-961 Mueller Steam Specialty Co., 1010 Spence Engineering Co., 933 Warren Webster & Co., 954-957 Baker Ice Machine Co., 866 Crane Company, 968-969 Frick Company, 869 Grinnell Co., Inc., 944-946, 1007 Henry Valve Company, 920 United States Register Co.. 904 Vilter Manufacturing Co.. 876 Henry Furnace & Foundry Co., 822 Iron Fireman Mfg. Co., 990-991 Meyer Furnace Company, 823 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 Webster Engineering Co., 993 Westinghouse Elec. & Mfg. Co., 808-809 Westinghouse Elec. & Mfg. Co., Worthington Pump & Machinery Williams Oil-O-Matic Heating 808-809 Co.. 874-875 Corporation, 820 Wright-Austin Co., 1011 York Ice Machinery Corp., 811 FEEDERS, Water Kieley & Mueller, Inc., 1009 McDonnell & Miller, 960-961 Mueller Steam Specialty Co., 1010 Wright-Austin Co., 1011 FITTINGS. Pipe, Solder Crane Company. 968-969 FITTINGS, Pipe, Sweat FUEL BURNING EQUIPMENT, Automatic (See Burners, Auto matic; Coal Burners, Automatic; Furnace Burners; Gas Burners; 0*7 Burners; Stokers) FELT, Sound Deadening Barrett Company, 1026 Carey, Philip, Co.. 1027 Ehret Magnesia Mfg. Co., 1030 1031 Johns-Manville, 1040-1041 Ruberoid Company. 1046-1047 Western Felt Works, 1050 American Radiator & Standard Sanitary Corp., 962-965 Crane Company, 968-969 FITTINGS, Welded American Rolling Mill Co., 907 Crane Company, 968-969 Grinnell Co., Inc., 944-946, 1007 York Ice Machinery Corp., 811 - FURNACE PIPE Johns-Manville, 1040-1041 Meyer Furnace Company, 823 FURNACE REGULATORS (See Regulators, Furnace) FURNACES, Electric FELT. Insulating (See Insulation. Felt) FLOATS, Metal (See Trap and Valve) General Electric Company, 816-817.. 892-893 Westinghouse Elec. & Mfg. Co., 808-809 * FILTERS, Air (See also Air Clean ing Equipment) Air-Maze Corporation, 844-845 American Air Filter Co., Inc.. 846 847 . American Radiator & Standard Sanitary Corp., 962-965 Coppus Engineering Corp., 848 Davies Air Filter Corp., 849 Detroit Lubricator Co., 914-915 Martocello. Jos. A. & Sons, 861 Owens-Coming Fiberglas Corp., 850-851 H. J. Somers, Inc., 854 Staynew Filter Corp., 852-853 Westinghouse Elec. & Mfg. Co., 808-809. 855 FIREBRICK', Insulating Babcock & Wilcox, 966 Johns-Manville, 1040-1041 Arthur Harris & Co., 995 Wright-Austin Co., 1011 FLOOR AND CEILING PLATES American Radiator & Standard Sanitary Corp., 962-965 Camegie-lllinois Steel Corp., 909 Crane Company. 968-969 Grinnell Co., Inc., 944-946. 1007 FLUE GAS ANALYSIS Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 Leed & Northrup Co., 924 Minneapolis-Honeywell Regulator Co., 926-927 FORCED-AIR DUCTS and .FIT TINGS (See Ducts, Fittings) FURNACES, Warm Air Acme Heating & Ventilating Co., Airtemp Div., Chrysler Corp., 812- Airtherm Manufacturing Co., 827 American Radiator & Standard Sanitary Corp., 962-965 Carrier Corporation,'804 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 Fitzgibbons Boiler Co., 970-97 L Gar Wood Industries, 818-819 General Electric Company, 816-817, 892-893 Henry Furnace & Foundry Co., 822 Meyer Furnace Co., The, 823 . L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 Pocahontas Fuel Co., 826 Spencer Heater Division, 980-981 Numerals fallowing Manufacturers' Names refer to pages in the Catalog Data Section 1073 HEATING .VENTILATING AIR CONDITIONING GUIDE 1940 United States Radiator Corp., 982- Baker Ice Machine Co., Inc., 866 Mercoid Corporation, 928 Bristol Company, 916 Minneapolis-Honeywell Regulator Westinghouse Elec. & Mfg. Co., Crane Company, 968-969 Co., 926-927 808-809, 855 C. A. Dunham Co., 942-943 . Spence Engineering Co., 933 Manning, Maxwell & Moore, Inc., United States Gauge Co., 936 925 - Warren Webster & Co., 954-957 GAGE BOARDS Mercoid Corporation, 928 . Baker Ice Machine Co.. 866 Bristol Company, The, 916 Frick Company, 869 Manning, Maxwell & Moore,- Inc., 925 Minneapolis-Honeywell Regulator Co.. 926-927 Spence Engineering Co., 933 Taylor Instrument Companies, 934 935 ' United States Gauge Co., 936 Minneapolis-Honeywell Regulator Co., 926-927 Spence Engineering Co., 933 Taylor Instrument Companies, 934 935 Trane Company, The, 838-839 United States Gauge Co., 936 GAGES, Steam American Radiator & Standard Sanitary Corp., 962-965 GAGES. Water American Radiator & Standard Sanitary Corp., 962-965 , Baker Ice Machine Co., 866 - Bristol Company, 916 Crane Company, 968-969 Detroit Lubricator Co., 914-915 Frick Company, 869 Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 ' Manning, Maxwell & Moore, Inc., Anderson Products, Inc., 1001 GAGE GLASSES Bristol Company, 916 Crane Company, 968-969 American Radiator & Standard C. A. Dunham Co., 942-943 - 925 Mercoid Corporation, 928 - Minneapolis-Honeywell Regulator Co., 926-927 Sanitary Corp., 962-965 Crane Company, 968-969 Jenkins Bros., 1132 Yarnall-Waring Co., 1103 . Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Manning, Maxwell & Moore, Inc., 925 . Taylor Instrument Companies, 934 935 < United States Gauge Co., 936 Wright-Austin Co., 1011 . Yarnall-Waring Co., 1012 Mercoid Corporation, 928 GAGES, Altitude Minneapolis-Honeywell Regulator' American Radiator & Standard Sanitary Corp., 962-965 Bell & Gossett Company, 941 . Bristol-Company, The, 916 Crane Company, 968-969 Mercoid Corporation, 928 Co., 926-927 Spence Engineering Co., 933 . Taylor Instrument Companies, 934 935 . United States Gauge Co., 936 Warren Webster & Co., 954-957 GAS BURNERS Airtemp Div. Chrysler Corp., 812 813 .... American Radiator & Standard Sanitary Corp., 962-965 Barber Gas Burner Co., 992 : Taylor Instrument Companies, 934 Coppus Engineering Corp., 848 935 ' United States Gauge Co., 936 GAGES, Tank . Crane Company, 968-969 Deled Appliance Div., General Detroit Lubricator Co., 914-915 Motors Sales Corp., 814-815 . Frick Company, 869 Henry Furnace & Foundry Co., 822 GAGES, Ammonia . Julien P. Friez & Sons, Div. of Spencer Heater Division, 980-981 Baker Ice Machine Co.. 866 Crane Company, 934-935 Martocello, Jos. A. & Co., 861 Mercoid Corporation, 928 United States Gauge Co., 939 Vilter Manufacturing Co., 876 Bendix Aviation Corp., 917 Todd Combustion Equipment, Inc., Minneapolis-Honeywell Regulator' 994 Co., 926-927 Webster Engineering Co., 993 Taylor Instrument Companies, 934- Westinghouse Elec. & Mfg. Co., 935 808-809 Wright-Austin Co., 1011 ' York Ice Machinery Corp., 811 GASKETS, Asbestos GAGES, Vacuum Crane Company, 968-969 GAGES, Compound Anderson. Products. Inc., 1001 Ehret Magnesia Manufacturing Co., American Radiator & Standard Sanitary Corp., 962-965 ' Crane Company, 968-969 Dole Valve Company, 1006 C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 . Manning, Maxwell & Moore, Inc., 925 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 United States Gauge Co., 936 ' Warren Webster & Co., 954-957 . Bristol Company, 916 Crane Company, 968-969 . C. A. Dunham Company, 942-943 ' Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 . Hoffman Specialty Co., Inc., 948- 949 \ Illinois Engineering Co., 950-951 Manning, Maxwell & Moore, Inc., 925 . Mercoid Corporation, 928 ! Minneapolis-Honeywell Regulator Co., 926-927 ~ Spence Engineering Co.', 933 Taylor Instrument Companies, 934 935 1030=1031 Frick Company 869 ' Jenkins Bros., 1008 Johns-Manville, 1040-1041 Ruberoid Co., The, 1046-1047 GASKETS, Cork . . Armstrong Cork Company, 1025 Crane Company, 968-969 . Johns-Manville, 1040-1041 Mundet Cork Corp., 1044 ` GASKETS, Felt GAGES, Liquid Level Bristol Company, 916 Henry Valve Company, 920 Taylor Instrument Companies, 934 935 . Minneapolis-Honeywell Regulator Co.. 926-927 GAGES, Pressure American Radiator & - Standard Sanitary Corp., 962-965 Anderson Products, Inc., 1001 Trane Company, The, 838-839 United States Gauge Co., 936 Warren Webster & Co., 954-957 GAGES, Vapor Bristol Company, The, 916 Crane Company, 968-969 . C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Manning, Maxwell & Moore, Inc., 925 Western Felt Works, 1050 .. GASKETS, Rubber Crane Company, 968-969 . Ehret Magnesia Manufacturing Co., 1030-1031 Frick Company, 869 Jenkins Bros., 1008 Johns-Manville, 1040-1041 ` GLASS (See Insulation, Double Class) - :. Please mention THE GUIDE 1940 when writing ot Advertisers INDEX TO MODERN EQUIPMENT GOVERNORS, Pump Buffalo Forge Company, 8& Crane Company, 968-969 Kieley & Mueller, Inc., 1009 Mueller Steam Specialty Co., Inc., 1010 Spence Engineering Co., 933 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 C. A. Dunham Co., 942-943 Fedders Manufacturing Co., 828 G & O Manufacturing Co., 865 General Electric Company. 816-817. 892-893 Ilg Electric Ventilating Co.. 884 McCord Radiator & Mfg. Co., 834 McQuay, Incorporated, 830-831 Modine Manufacturing Co., 832-833 John J. Nesbitt. Inc., 836 GRATES FOR BOILERS AND Niagara Blower Company, 806 FURNACES . , ,, .Refrigeration Economics Co., 837 American Coolair Corp., 878-879 Combustion Engineering Co., 988 Fitzgibbons Boiler Co., Inc., 970- 971 . International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 L. J. Mueller Furnace Co., 824-825 UnitHeater and Cooler Co., 840 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Unit Heater & Cooler Co., 840 Westinghouse Elec. & Mfg. Co., 808-809, 855 L. J. Wing Mfg. Co., 890-891 York Ice Machinery Corp., 811 Young Radiator Company, 841 Henry Furnace & Foundry Co., 822 Kewanee Boiler Corp., 974-977 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 . Williams Oil-O-Matic Heating Corp., 820 Westinghouse Elec. & Mfg. Co., 808-809,855 . Young Radiator Company, 841 HEATERS, Blast Aerofin Corporation, 862-864 American Blower Corp., 802-803 American Radiator & Standard Sanitary Corp., 962-965 Autovent Fan & Blower Co., 877 Bayley Blower Company, 880 Buffalo Forge Company, 881 United States Radiator Corp., 982 Carrier Corporation, 804 983 Clarage Fan Company, 805 . HEATERS, Air GRILLES, REGISTERS AND ORNAMENTAL METAL WORK (See also Registers) Acme Heating & Ventilating Co., 821 Aerofin Corporation. 862-864 : Airtemp Div., Chrysler Corp.. 812 American Blower Corp., 802-803 . 813 American Coolair Corp., 878-879 Airtherm Manufacturing Co., 827 Anemostat Corp. of America, 895 American Blower Corp., 802-803 Auer Register Co., The. 896 American Radiator & Standard Barber-Colman Co., 897, 913' Sanitary Corp., 962-965 Hart & Cooley Manufacturing Co., Autovent Fan & Blower Co., 877 898-899 Baker Ice Machine Co., 866 ' Hendrick Mfg. Co , 900 . Buffalo Forge Company, 881 Independent Register Co., 901 Carrier Corporation, 804 McQuay Incorporated, 830-831 Clarage Fan Company, 805 . C. A. Dunham Co., 942-943 Fedders Manufacturing Co., 828 G & O Manufacturing Co., 865 McQuay, Incorporated, 830-831' Modine Mfg. Co., 832-833 John J. Nesbitt, Inc., 836 Niagara Blower Company, 806 Refrigeration Economics Co., 837 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Unit Heater & Cooler Co., 840 . Westinghouse Elec. & Mfg. Co.; 808-809, 855 L. J. Wing Mfg. Co., 890-891 Young Radiator Co., 841 L. J. Mueller Furnace Co., 824-825 Combustion Engineering Co., 988 Trane Company, The, 838-839 Tuttle & Bailey, Inc., 902-903 Delco Appliance Div., General Motors Sales Corp., 814-815 HEATERS, Cabinet United States Air Conditioning Corp., 810 United States Register Co., 904 Waterloo Register Co., 905 Wickwire Spencer Steel Co., 906 HANGERS, Pipe American Radiator & Standard Sanitary Corp., 962-965 Baker Ice Machine Co., 866 . Crane Company, 968*969' Frick Company, 869 Grinnell Co., Inc., 944^946, 1007 Ric-wiL Company, The, 1016 C. A. Dunham Co., 942-943 Fedders Manufacturing Coi, 828 Gar Wood Industries, Inc., 818-819 General Electric Company, 816-817, 892-893 Grinnell Co., Inc., 944-946, 1007 Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating Co., 884 Iron Fireman Mfg. Co., 990-991 Mario Coil Company, 871 McCord Radiator & Mfg. Co., 834 McQuay, Incorporated, 830-831 Meyer Furnace Company. 823 Modine Mfg. Co,, 832-833 Herman Nelson Corp., 835 John J. Nesbitt, Inc., 836 Delco Appliance Div., General Motors Sales Corp., 814-815 , C. A. Dunham Co., 942-943 . Fedders Manufacturing Co., 828- General Electric Company, 816-817, 892-893 ... . Henry Furnace & Foundry Co., 822' McCord Radiator & Mfg. Co., 834 McQuay, Incorporated, 830-831 Modine Mfg. Co., 832-833 John J. Nesbitt, Inc., 836 ' . ' Trane Company, The, 838-839 - Unit Heater & Cooler Co., 840 Weil-McLain Company, 984 Young Radiator Co., 841 Vilter Manufacturing Co., 876 Niagara Blower Co., 806 '. ' Refrigeration Economics Co., 837 B. F. Sturtevant Co., 886 HEATERS, Electric HANGERS, Radiator' American Radiator & Standard Sanitary Corp., 962-965 Crane Company, 968-969 Grinnell Co., Inc., 944-946, 1007 Trane Company. The, 838-839 Unit Heater and Cooler Co., 840 ' .Autovent Fan & Blower Co., 877 United States Air Conditioning General Electric Company, 816-8171 Corp., 810 892-893 Westinghouse Elec. & Mfg. Co., Grinnell Co., Inc., 944-946, 1007 808-809, 855 Ilg Electric Ventilating Co.; 884 L. J. Wing Mfg. Co., 890^891 . B. F. Sturtevant Co., 886 HEADS, Exhaust Crane Company, 968-969 Kieley & Mueller, Inc., 1009' York Ice Machinery Corp., 811 Young Radiator Company, 841 Weil-McLain Company, 984 ! Westinghouse Elec. & Mfg. Co., 808-809,855 . Young Radiator Company, 841 Wright-Austin Co., 1011 HEATERS, Automatic Hot Water, Domestic HEADS, Sprinkler Grinnell Co., Inc., 944-946, 1007 HEAT SURFACE Aerofin Corporation, 862-864 American Blower Corp., 802-803 American Radiator & Standard Sanitary Corp., 962-965 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Fitzgibbons Boiler Co., Inc., 970 971 . Gar Wood Industries, Inc., 818-819 HEATERS, Feed Water Brownell Company, 985 Cochrane Corp., 1005 General Electric Company, 816-817, 892-893 . Westinghouse Elec. & Mfg. Co., 808-809, 855 Worthington Pump & Machinery Corp., 874-875 Numerals following Manufacturers' Names refer to pages In the Catalog Data Section HEATING VENTILATING AIR CONDITIONING GUIDE 1940 HEATERS, Fuel Oil Airtemp Div., Chrysler Corp., 812 813 . American District Steam Co., 1000, 1014 Bell and Gossett Co., 941 Delco Appliance Div., General Motors Sales Corp., 814-815 American Radiator & "Standard Sanitary Corp.. 962-965 Bell & Gossett Co., 941 Brownell Company, 985 Burnham Boiler Corp., 967 Crane Company, 968-969 General Electric Company, 816 817, 892-893 HEATING SYSTEMS. Air Acme Heating & Ventilating Co.. 821 Airtemp Div., Chrysler Corp., 812 813 Airtherm Manufacturing Co., 827 American Blower Corp., 802-803 ' American Radiator & Standard. . Sanitary Corp., 962-965 ' General Electric Company, 816-817, Autovent Fan & Blower Co., 877 . > 892-893 Kewanee Boiler Corp., 974-977 HEATERS, Tank Buffalo Forge Company. 881 Burnham Boiler Corp., 967 -' Meyer Furnace Co., 823 Todd Combustion Equipment, Inc., 994 Williams Oil-O-Matic Heating Corp., 820 American District Steam Co., 1000, 1014 American Radiator & Standard Sanitary Corp.. 962-965 . Bel! & Gossett Co.. 941 Burnham.Boiler Corp., 967 Carrier Corporation, 804 ' Clarage Fan Company, 805 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Crane Company, 968-969 Fedders Manufacturing Co., 828 HEATERS. Gas Fitzgibbons Boiler Co., Inc., 970 Gar Wood Industries, Inc., 818-819 971 General Electric Company, 816 American Radiator & Standard Grinnell Co.,_Inc., 944-946, 1007 817, 892-893 Sanitary Corp., 962-965 International Boiler Works Co., 973 Henry Furnace & Fo%idry Co., 822 Crane Company, 968-969 Kewanee Boiler Corp., 974-977 Ilg Electric Ventilating Co., 884 Burnham Boiler Corp., 967 L. J. Mueller Furnace Co., 824-825 McQuay, Incorporated, 830-831 C. A. Dunham Co.. 942-943 Pacific Steel Boiler Div., U. S. Meyer Furnace Co., The, 823 General Electric Company, 816-817, 892-893 Kewanee Boiler Corp., 974-977 Meyer Furnace Company. 823 HEATERS. Hot Water Service Radiator Corp., 978 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 . Weil-McLain Company, 984 Westinghouse Elec. & Mfg. Co., 808-809. 855 Modine Mfg. Co.. 832-833 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 John J. Nesbitt. Inc., 836 Niagara Blower Company, 806 Spencer Heater Division, 980-981 B. F. Sturtevant Co., 886 Trane Company. The, 838-839 American District Steam Co., 1000, Unit Heater and Cooler Co., 840 1014 American .. Radiator & Standard HEATERS, Unit United States Radiator Corp., 982 983 Sanitary Corp., 962-965 Airtherm Manufacturing Co.. 827 Westinghouse Elec. & Mfg. Co., Bell & Gossett Co., 941 Brownell Company, 985 Burnham Boiler Corp., 967 Crane Company, 968-969 American Blower Corp., 802-803 Autovent Fan & Blower Co., 877 Bayley Blower Company, 880 Buffalo Forge Company, 881 808-809, 855 L. J. Wing Mfg. Co., 890-891 Young Radiator Company, 841 York Ice Machinery Corp., 811 Fitzgibbons Boiler Co., Inc., 970 Burnham Boiler Corp., 967 971 Henry Furnace & Foundry Co., 822 International Boiler Works Co., 973 Kewanee Boiler Corp., 974-977 Carrier Corporation. 804 Clarage Fan Company, 805 Crane Company, 968-969 Delco Appliance Div., General HEATING SYSTEMS, Automatic Airtemp Div., Chrysler Corp., 812 L. J. Mueller Furnace Co;, 824-825 J. J. Nesbitt, Inc., 836 Pacific Steel Boiler Div., U. S. Radiator Corp., 978 Spencer Heater Division, 980-981 Motors Sales Corp., 81* 4-815 C. A. Dunham Co., 942-943 Fedders Manufacturing Co., 828 Grinnell Co., Inc.. 944-946, 1007 Ilg Electric Ventilating Co., 884 813 American Radiator & Standard Sanitary Corp., 962-965 Anderson Products, Inc., 1001 Burnham Boiler Corp., 967 Trane Company, The, 838-839 Westinghouse Elec. & Mfg. Co.. 808-809, 855 HEATERS, Indirect Aerofin Corporation, 862-864 American District Steam Co., 1000, 1014 American Radiator & Standard p Sanitary Corp., 962-965 Bell & Gosssett Co., 941 Crane Company, 968-969 Tedders Manufacturing Co., 828 Fitzgibbons Boiler Co., Inc., 970 971 Kewanee Boiler Corp., 974-977 McQuay, Incorporated, 830-831 Unit Heater and Cooler Co., 840 Iron Fireman Mfg. Co., 990-991 Carrier Corporation, 804 tF;. Jaden Manufacturing 'C"''oA..,' '8-"29v Crane Company, 968-969 McCord Radiator 8c Mfg. Co., 834. McQuay Incorporated, 830-831 De~Mlc*oot`orAsp"SpalilaesncCeorpD.,ivo8.1,,4a -8eG1,ee5neral Modine Mfg. Co.. 832-833 Herman Nelson Corp., 836 C. A. Dunham Co., 942-943 Gar Wood Industries, Inc., 818-819 John J. Nesbitt. Inc., 836 General Electric Company, 816 Niagara Blower Company, 806 817, 892-893 Refrigeration Economics Co., 837 Henry Furnace & Foundry Co., 822 B. F. Sturtevant Co., 886 Hoffman Specialty Co., Inc., 948 Trane Company. The, 838-839 949 Unit Heater and Cooler Co., 840 Illinois Engineering Co., 950-951 United States Air Conditioning Iron Fireman Mfg. Co., 990-991 Corp.. 810 Meyer Furnace Company, 823 United States Radiator Corp., 982 MotorStoker Division Hersbey Ma 983 Warren Webster & Co., 954-957 chine & Fdy. Co., 989 . L. J. Mueller Furnace Co., 824-825 L. J. Wing Mfg. Co.. 890-891 Herman Nelson Corp., 835 Young Radiator Company, 841 Pocahontas Fuel Co.. 826 Sarco Co., Inc., 952-953 L. J. Wing Mfg. Co., 890-891 Spence Engineering Co.. 933 HEATERS, Unit, Gas Fired Spencer Heater Division, 980-981 Trane Company, The, 938-939 . HEATERS, Refuse Burning Airtherm Manufacturing Co., 827 United States Radiator Corp., 982 Kewanee Boiler Corp., 974-977 L. J. Mueller Furnace Co., 824-825 HEATERS, Storage American District Steam Co., 1000, American Radiator & Standard Sanitary Corp., 962-965 Buffalo Forge Company, 881 Crane Company, 968-969 C. A. Dunham Co., 942-943 McQuay, _I_n_c_o__r_p_o_r_a__te__d_,__8_3_0_-_8_3__1 t. J. Mueller Furnace Co., 824-825 983 Westinghouse Elec. & Mfg. Co., 808-809, 855 Williams Oil-O-Matic Heating Corp., 820 Wa-r..r..e..n....W... --ebster & Co., 954-957 L. J. Wing Mfg. Co., 890-891 1014 Trane Company, The, 838-839 York Ice Machinery Corp., 811 Please mention THE GUIDE 1940 when writing to Advertisers 1076 INDEX TO MODERN EQUIPMENT HEATING SYSTEMS, Furnace Herman Nelson Corp., 835 HEATING SYSTEMS, Vacuum Acme Hearing & Ventilating Co., 821 Airtemp Div., Chrysler Corp., 812 813 , Airtherm Manufacturing Co., 827 American Radiator & Standard Sanitary Corp., 962-965 Carrier Corporation. 804 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 Gar Wood Industries, Inc., 818-819 General Electric Company, 816 817, 892-893. Henry Furnace & Foundry Co., 822 Meyer Furnace Company, 823 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 Spencer Heater Division, 980-981 United States Radiator Corp., 982 983 Spencer Heater Division, 980-981 Trane Company, The. 838-839 United States Radiator Corp., 982 983 Westinghouse Elec. & Mfg. Co., 808-809. 855 Williams Oil-O-Matic Heating Corp., 820 L. J. Wing Mfg. Co.. 890-891 HEATING SYSTEMS. Oil Fired Acme Hearing & Ventilating Co., 821 Airtemp Div., Chrysler Corp., 812 813 Airtherm Manufacturing Co., 827 American Radiator & Standard Sanitary Corp., 962-965 Barnes & Jones. Inc., 940 American Radiator & Standard Sanitary Corp., 962-965 Barnes & Jones, Inc., 940 Burnham Boiler Corp., 967 Crane Company. 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Gar Wood Industries, Inc., 818-819 General Electric Company, 816 817, 892-893 William S. Haines & Co., 947 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 L. J. Mueller Furnace Co., 824-825 Sarco Company, Inc., 952-953 Spencer Heater Division, 980-981 Trane Company, The, 838-839 United States Radiator Corp., 982 Westinghouse Elec. & Mfg. Co., 808-809. 855 Williams Oil-O-Matic Heating Corp., 820 Carrier Corporation, 804 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 Gar Wood Industries, Inc., 818-819 983 Warren Webster & Co., 954-957 Westinghouse Elec. & Mfg. Co., 808-809, 855 Williams Oil-O-Matic Heating General Electric Company, 816 Corporation, 820 817, 892-893 HEATING SYSTEMS, Gas Fired Henry Furnace & Foundry Co., 822 Acme Heating & Ventilating Co., 821 Airtemp Div., Chrysler Corp., 812 813 . Airtherm Manufacturing Co., 827 American Blower Corp., 802-803 American Radiator & Standard Sanitary Corp., 962-965 ' Barnes & Jones, Inc-, 940 Burnham Boiler Corp., 967 Carrier Corporation, 804 Crane Company, 968-969 . Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 Kewanee Boiler Corp., 974-977 Meyer Furnace Co., The, 823 HEATING SYSTEMS, Vapor L. J. Mueller Furnace Co., 824-825 Airtemp Div., Chrysler Corp., 812 Herman Nelson Corp., 835 813 Spencer Heater Division, 980-981 Trane Company, The, 838-839 American District Steam Co., 1000, 1014 United States Radiator Corp., 982 American Radiator & Standard 983 ` Sanitary Corp., 962-965 Westinghouse Elec. & Mfg. Co., Barnes & Jones, Inc., 940 808-809, 855 Crane Company, 968-969 Williams Oil-O-Matic Heating Delco Appliance Div., General Corp., 820 Motors Sales Corp., 814-815 -C. A. Dunham Co., 942-943 Gar Wood Industries, Inc., 818-819 HEATING SYSTEMS, Steam General Electric Company, 816 817,892-893 . Gar Wood Industries, Inc., 818-819 General Electric Company, 816 817, 892-893 Henry Furnace & Foundry Co., 822 Kewanee Boiler Corp., 974-977 Meyer Furnace Co., The, 823 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 Spencer Heater Division, 980-981 Trane Company, The, 838-839 United States Radiator Corp., 982 983 Westinghouse Elec. & Mfg. Co., 808-809. 855 Airtemp Div., Chrysler Corp., 812 813 Airtherm Manufacturing Co.. 827 American Radiator & Standard Sanitary Corp., 962-965 Anderson Products, Inc., 1001 Barnes & Jones, Inc., 940 Bell & Gossett Co., 941 Burnham Boiler Corp., 967 Carrier Corporation, 804 Crane Company, 968-969 ' Delco Appliance Div., General Motors Sales Corp., 814-815 C. A. Dunham Co., 942-943 William S. Haines & Co., 947 Hoffman Specialty Co., Inc-, 948 949 Illinois Engineering Co., 950-951 L. J. Mueller Furnace Co., 824-825 Herman Nelson Corp., 835 Sarco Company, Inc., 952-953 Spencer Heater.Division, 980-981 Trane Company, The, 838^839 United States Radiator Gorp., 982 983 Warren Webster & Co., 954-957 Westinghouse Elec. & Mfg. Co., 808-809. 855 Gar Wood Industries, Inc.. 818-819 Williams Oil-O-Matic Heating General Electric Company, 816 Corp., 820 ` HEATING SYSTEMS, Hot 817,892-893 . Water .William S. Haines & Co.. 947. Hoffman Specialty Co., Inc., 948 Airtemp Div., Chrysler Corp., 8i2- 949 813 - . Illinois Engineering Co., 950-951 American Blower Corp., 802-803 ` Kewanee Boiler Corp., 974-977 American Radiator &. Standard L. J. Mueller Furnace Co., 824-825 Sanitary Corp.. 962-965 Herman Nelson Corp., 835 Bell & Gossett Co., 941 Ric-wiL Company, The, 1016 Burnham Boiler Corp., 967 Sarco Company, Inc., 952-953 Crane Company, 968-969 Spence Engineering Co., 933 Delco Appliance Div., General Spencer Heater Division, 980-981 Motors Sales Corp., 814-815 Trane Company^ The, 838-839 Gar Wood Industries, Inc., 818-819 Unit Heater & Cooler Co., 840 General Electric Company, 816 United States Radiator Corp., 982- 817, 892-893 . 983 Henry Furnace & Foundry Co., 822 Warreij-Webster & Co., 954-957 ^Hoffman Specialty Co., Inc.. 948- Westinghouse Elec. & Mfg. Co., Kewanee Boiler Corp., 974-977 McQuay, Incorporated, 830-831 L. J. Mueller Furnace Co., 824-825 808-809.855 . Williams Oil-O-Matic Heating Corp., 820 ' L. J. Wing Mfg. Co., 890-891 HOSE, Refrigerant Charging Henry Valve Company, 920 HOT WATER HEATING SYS TEMS (See Heating Systems, Hot Water) HUMIDIFIERS Air-Maze Corp., 844-845 . American Blower Corp., 802-803 American Moistening Co., 857 American. Radiator & Standard Sanitary Corp., 962-965 < . Armstrong Machine Works, 1002 1003 Baker Ice Machine Co., 866 Numerals following Manufacturers' Names refer to pages In the Catalog Data Section 1077 HEATING VENTILATING AIR CONDITIONING GUIDE.1940 Binks Manufacturing Co., 858-859 Unit Heater and Cooler Co., 840 Palmer Company, 929 . Buffalo Forge Company, 881 United States Air Conditioning Powers Regulator Co., 930-931 Burnham Boiler Corp., 967 Corp., 810 Taylor Instrument Companies, 934 Carrier Corporation, 804- ' 935 Clarage Fan Company,- 805 Delco Appliance Div., General Motors Sales Corp., 814-815 General Electric Company, 816 HUMIDITY CONTROL American Moistening Co., 857 Barber-Colman Co., 897, 913 Bristol Company, The. 916 United States Gauge Co., 936 Westinghouse Elec. & Mfg. Co.. 808-809, 855 817,892-893 . Grinnell Co., Inc., 944-946, 1007_ Henry Furnace & Foundry Co., 822 Ilg Electric Ventilating Co., 884 Johnson Service Co., 922-923 McQuay, Incorporated, 830-831 Meyer Furnace Co., The, 823 L. J. Mueller Furnace Co., 824-825 Niagara Blower Company, 806 Parks-Cramer Company, 807 H. J. Somers, Inc., 854 - B. F. Sturtevant Co., 886 . Trane Company, The, 838-839 United States Air Conditioning Corp., 810 Unit Heater & Cooler Co., 840 Weil-McLain Company, 984 Westinghouse Elec. & Mfg. Co., Carrier Corporation, 804 Delco Appliance Div., General. Motors Sales Corp., 814-815 Detroit Lubricator Co., 914-915 Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 General Electric Company, 816 817, 892-893 Grinnell Co., Inc., 944-946, 1007 Henry Furnace & Foundry Co., 822 Johnson Service Co., 922-923 Manning, Maxwell & Moore, Inc., 925 Mercoid Corporation, The, 928 Minneapolis- Honeywell Regulator Co., 926-927 Niagara Blower Company,-806 808-809, 855 Parks-Cramer Company, 807 INSULATION, Building Aluminum Aircell Insulation Co.. 1023 ' American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Barrett Company, 1026 Carey, Philip, Co., 1027 Celotex Corporation, The, 1028 1029 . Chamberlin Metal Weather Strip Co., 1018-1019 * Eagle-Picher Lead Co.,Tl032 Ehret Magnesia Manufacturing Co., 1030-1031 General Insulating & Mfg. Co., 1033 Hinde & Dauch Paper Co., 1034 1035 Insulite Company, Thet 1036-1037 . - - Penn Electric Switch Co., 932 Insulation Industries. Inc;, 1038 HUMIDIFIERS, Central Plant Powers Regulator Co., 930-931. Taylor Instrument Companies, 934 International Fibre Board, Ltd., 1039 Acme Heating & Ventilating Co., 935 White-Rodgers Electric Co., 937 Johns-Manville, 1040-1041 Kimberly-Clark Corp., 1042-1043 - American Blower Corp., 802-803 ' Baker Ice Machine Co., 866 ' HUMIDITY RECORDERS and Bayley Blower Company, 880 Indicators Buffalo Forge Company, 881 . Carrier Corporation, 804 ' Clarage Fan Company, 805 Delco Appliance Div., General Motors Sales Corp., 814-815 . ' Gar Wood Industries, Inc., 818-819 General Electric Company, 816^ 817, 892-893 Ilg Electric Ventilating Co., 884 . Johnson Service Company, 922-923 Meyer Furnace Co., The, 823 Bristol Company, The, 916 Julien P. Friez & Sons. Div. of ; Bendix Aviation Corp., 917. Leeds & Northrop,Co., 924 Minneapolis-Honeywell Regulator Co.. 926-927 Palmer Company, 929 - Powers Regulator Co.`, 930-931 Taylor Instrument Companies, 934 935 - Mundet Cork Corp., 1044 Owens-Corning Fiberglas Corp., 850-851 Pacific Lumber Co., The. 1045 Ruberoid Co., The, 1046-1047 Standard Lime & Stone Co., 1048 United States Gypsum Co., 1049 Western Felt Works, 1050 Wood Conversion Company, 1051 INSULATION, Double Glass Libby-Owens-Ford Glass Co., 1020 1021 Niagara Blower Company, 806 - Parks-Cramer Company, 807 Powers Regulator Co., 930-931 HYGROMETERS (See also Hu_ midity Recorders and Indicators) ' H. J. Somers, Inc., 854 . American Moistening Co., 857 ' B. F. Sturtevant Co., 886 ' Bristol Company, 916 Trane Company, The, 838-839 Detroit Lubricator Go., 914-915 United States Air Conditioning Julien P. Friez & Sons, Div. of Corp., 810 ` Bendix Aviation Corp., 917 ' Westinghouse Elec. & Mfg. Co., Grinnell Co., Iiic., 944-946, 1007 . 808-809.855 Johnson Service Co., 922-923 York Ice Machinery Corp., 811 Palmer Company, 929 Taylor Instrument Companies, 934 935 . INSULATION, Ducts, Ventilat ing, Air Conditioning Aluminum Aircell Insulation Co., 1023 American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Barrett Company, 1026 Carey, Philip, Co., 1027 Celotex Corporation, 1028-1029 Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030 1031 . HUMIDIFIERS. Unit Airtemp Div., Chrysler Corp.,.812-1 813 1 . American Blower Corp., 802-803 General Insulating & Mfg. Co., INDUCED DRAFT COOLING 1033 TOWERS (See also Coding Hinde & Dauch Paper Co., 1034 Towers, Forced Draft, Mechanical. 1035 Draft) Insulation Industries, Inc., 1038 American Moistening Co., 857 ; Baker Ice Machine Co., 866 Insulite Company, The, 1036-1037 Armstrong Machine Works, 1002 Binks Manufacturing Co., 858-859 International Fibre Board, Ltd.,, 1003 , Buffalo Forge Company, 881 Burnham Boiler Corp., 967 Carrier Corporation, 804 Clarage Fan Company, 805 Buffalo Forge Company, 881 Marley Company, 860 Unit Heater &. Cooler Co., 840 York Ice Machinery Co., 811 1039. Johns-Manville, 1040-1041 Mundet Cork Corp., 1044 Owens-Corning Fiberglas 850-851 Corp., Delco Appliance Div., General Motors Sales Coro., 814-815 . General Electric Company, 816^ INSTRUMENTS, and Recording Indicating Pacific Lumber Co., The, 1045 Ruberoid Co., The, 1046-1047 Standard Lime & Stone Co., 1048 817, 892-893 . Bristol Company, The, 916 United States Gypsum Co., 1049 Grinnell Co.. Inc., 944-946, 1007 Cochrane Corp., 1005 . Western Felt Works, 1050 Marley Company, The, 860 ' Julien P. Friez & Sons, Div. of Wood Conversion Company, 1051 McQuay, Incorporated, 830-831 - Bendix Aviation Corp., 917 ' Niagara Blower Company, 806. Parks-Cramer Company, 807 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Illinois 921 Testing Laboratories, Inc.,. INSULATION, Felt Leeds & Northrop Co., 924 American Hair & Felt Co., 1024 Minneapolis-Honeywell Regulator Barrett Company, 1026 Tuttle & Bailey, Inc., 902-903 Co., 926-927 Carey, Philip, Co.; 1027 Please mention THE GUIDE 1940 when writing to Advertisers . . 1078 INDEX TO MODERN EQUIPMENT Eagle-Picher Lead Co., 1032 Insulation Industries, Inc., 1038 MECHANICAL DRAFT COOL Ehret Magnesia Mfg. Co., 1030 Johns-Manville. 1040-1041 1031 Owens-Corning Fiberglas Corp.. General Insulating & Mfg. Co., 850-851 . ING TOWERS {See also Cooling Towers, Forced Draft, Induced Draft) 1033 H. W. Porter & Co., 1015 Insulation Industries, Inc., 1038 Ric-wiL Company, The, 1016 Baker Ice Machine Co., 866 Johns-Manville, 1040-1041 Kimberly-Clark Corp., 1042-1043 Ruberoid Co., The, 1046-1047 Standard Lime & Stone Co., 1048 Binks Manufacturing Co., 858-859 Buffalo Forge Company, 881 - Ruberoid Co., 1046-1047 Underground Steam Construction Marley Company, 860 ' . Standard Lime & Stone Co., 1048 Co.. 1017 Unit Heater & Cooler Co., 840 . Western Felt Works, 1050 Wood Conversion Company,. 1038 York Ice Machinery Corp., 811 INSULATION, Pipes and Sur faces {See Coverings. Pipes and Surfaces) INSULATION, Magnesia Carey. Philip. Co., 1027 Ehret Magnesia & Mfg. Co., 1030 1031 Johns-Manville, 1040-1041 Ruberoid Co., The, 1046-1047 INSULATION, Window METALS, Perforated {See Perforated Metals) Chamberlin Meta] Weather Strip Co., 1018-1019 Ingersoll Steel & Disc Div., Borg- METERS, Air Wamer Corp., 1022 Libby-Owens-Ford Glass Co., 1020 . Bristol Company, The, 916 1021 Julien P. Friez & Sons, Div. of. Bendix Aviation Corp., 917 Illinois Testing Laboratories, 921 . LIME SCALE CONTROL Oakite Products, Inc., 856 Minneapolis-Honeywell Regulator Co., 926-927 ;; Taylor Instrument Companies, 934- INSULATION, Plastic Eagle-Picher Lead Co., 1032 . LIQUID LEVEL CONTROLS Alco Valve Co.. Inc., 912 METERS, Air Velocity . INSULATION, Refractory Babcock & Wilcox Co., 966 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 Johns-Manville, 1040-1041 INSULATION, Sound Deaden ing {See also Felt, Sound Deaden ing) Aluminum Aircell Insulation Co.. 102^ American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Bristol Company, The, 916 Anderson Products, Inc., 1001 Cochrane Corp., 1005 Julien P. Friez & Sons, Div.' of Detroit Lubricator Co., 914-915 Bendix Aviation Corp., 917 . Frick Company. 869 Illinois Testing Laboratories, 921 Johnson Service Co., 922-923 Minneapolis-Honeywell Regulator; Kieley & Mueller, Inc., 1009 ' Co., 926-927 . McDonnell & Miller, 960-961 Powers Regulator Co., 930-931 Minneapolis-Honeywell' .Regulator' Taylor Instrument Companies, 934- Co.. 926-927 Mueller Steam Specialty Co., Inc., 1010 Penn Electric Switch Co., 923 Spence Engineering Co., 933 Taylor Instrument Companies, 934 935 METERS, Condensation . American District Steam Co., 1000, 1014 , Barrett Company, 1026 Carey, Philip. Co., 1027 Celotex Corporation, 1028-1029 ' Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030 1031 LIQUID LEVEL GAGES Gages, Liquid Level) {See METERS, Feed Water ' Cochrane Corp., 1005 .. . Minneapolis-Honeywell Regulator Co., 926-927 . General Insulating & Mfg. Co.. LOUVERS 1033 American Coolair Corp., 878-879 METERS, Flow .. Hinde & Dauch Paper Co., 1034 1035 Anemostat Corp. of America, 895 Auer Register Co., 896 American District Steam Co., 1000, Insulation Industries. Inc., 1038 .Autovent Fan & Blower Co., 877 1014 . '` Insulite Company, The, 1036-1037 Buffalo Forge Company, 881 Bristol Company, The, 916 International Fibre Board; Ltd., Champion Blower & Forge Co., 882 Cochrane Corp., 1005 - 1039 . Clarage Fan Company, 805 , Leeds & Northrop Co., 924 Johns-Manville, 1040-1041 Hart & Cooley Mfg. Co., 898-899 Minneapolis-Honeywell Regulator Kimberly-Clark Corp., 1042-1043 Hendrick Mfg. Co., 900 Co., 926-927 , Mundet Cork Corp., 1044 Henry Furnace & Foundry Co., 822 Taylor Instrument Companies, 934- Owens-Corning Fiberglas Corp., Independent Register Co., 901 . 850-851 Trane Company, The, 838-839 Pacific Lumber Co., The, 1045 Tuttle & Bailey, Inc., 902-903 . H. W. Porter & Co., 1015 Unit Heater & Cooler. Co., The, 840 METERS, Steam Ruberoid Co., The, 1046-1047 Standard Lime & Stone Co., 1048 United States Gypsum Co., 1049 United States Register Co.. 904 ' Waterloo Register Co., 905 , American District Steam Co., 1000. 1014 . -, Western Felt Works, 1050 Cochrane Corp., 1005 ' . . Wood Conversion Company, 1051 MANHOLE COVERS, For Underground Systems Minneapolis-Honeywell Regulator Co., 926-927 . INSULATION, Underground Steam Pipe f American District Steam Co., 1000, 1014 E. B. Badger & Sons Co., 1004,1017 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030 1031 General Insulating & Mfg. Co., . 1033 American Coolair Corp., 878-879 American District Steam Co., 1000. 1014 H. W. Porter & Co., 1015 Ric-wiL Company, The, 1016 MECHANICAL DRAFT APPA RATUS {See also Blowers, Forced Draft) Binks Manufacturing Co., 858-859 MOTORS, Electric . -. Barber-Colman Co., 897, 913 General Electric Company, 816 817,892-893 ^ B. F. Sturtevant Co., 886 Wagner Electric Corp., 894 ` : Westinghouse Elec. & Mfg. Co;. 808-809,855 . ' Williams Oil-O-Matic Heating Corp., 820 . -` Numerals following Manufacturers' Names refer to pages in. the Catalog Data Section 1079 y\'"; . ; TOT! HEATING VENTILATING AIR CONDITIONING GUIDE 1940 NOISE ELIMINATORS (.See also Hose. flexible; Tubing, flexible-, Sound Deodeners; Vibration Absorters) OIL BURNERS, Variable Capa- city Todd Combustion Equipment, Inc., 994 PPIE, Cement Johns-Manville, 1040-1041 Ruberoid Co.. The. 1046-1047 Standard Lime & Stone Co., 1048 NOZZLES. Spray {See Spray Noz OIL BURNER TUBING, Flexible zles) (See Tubing, Flexible Metallic) OIL BURNER EQUIPMENT OIL TANK GAGES (See Tank Cages, OH) Airtemp Div., Chrysler Corp., 812 813 ` American Radiator & Standard ORIFICES, Flow Meter Sanitary Corp., 962-965 Crane Company, 968-969 Delco Appliance Div.,' General Motors Sales Corp., 814-815 Detroit Lubricator Co., 914-915 Bristol Company, The, 916 Cochrane Corp., 1005 4 Taylor Instrument Companies, 934 - 935 General Electric Company, 816 817, 892-893 Herman Nelson Corp., 835 Iron Fireman Mfg. Co., 990*991 L. J. Mueller Furnace Co., 824-825 Spencer Heater Division, 980-981 Todd Combustion Equipment, Inc. 994 Westinghouse Elec. & Mfg. Co., 808-809, 855 Williams Oil-O-Matic Heating Corp., 820 ORIFICES. Radiator Barnes & Jones, Inc., 940 Detroit Lubricator Co.. 914-915 C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Sarco Co., Inc., 952-953 Spence Engineering Co., 933 Trane Company, The, 838-839 Warren Webster & Co., 954-957 PIPE, Copper American Radiator & Standard Sanitary Corp., 962-965 Crane Company, 968-969 PIPE, Copper Bearing Steel " Bethlehem Steel Co., 908 Crane Company, 968-969 Jones & Laughlin Steel Corp., 910 * PIPE, Furnace (See Furnace Pipe) PIPE, Return Bends Crane Company. 968-969 Frick Company, 869 Grinnell Co., Inc., 944-946, 1007 Arthur Harris & Co., 995 Henry Valve Company, 920 Vilter Manufacturing Co., 876 PIPE, Steel OIL BURNER MOTORS (See Motors, Electric) OIL BURNERS Airtemp Div., Chrysler Corp., 812 813 American Radiator & Standard Sanitary Corp., 962-965 Babcock & Wilcox Co., 966 Combustion Engineering Co., 988 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corporation, 814 PACKING. Asbestos Barrett Company, 1026 Crane Company, 968-969 Ehret Magnesia Mfg. Co., 1031 Johns-Manville, 1040-1041 1030 American Rolling Mill Co., 907 Bethlehem Steel Co., 908 Carnegie-IHinois Steel Corp., 909 Crane Company, 968-969 Grinnell Co., Inc., 944-046, 1007 Jones & Laughlin Steel Corp., 910 Vilter Manufacturing Co., 876 PAINTING EQUIPMENT, Spray Binks Manufacturing Co., 858-859 PANELS. Insulated PIPE, Wrought Iron Crane Company, 968-969 Grinnell Co., Inc., 944-946, 1007 Vilter Manufacturing Co., 876 816 > Aluminum Aircell Insulation Co., Gar Wood Industries, Inc., 818-819 1023 General Electric Company, 816 Carey, Philip, Co., 1027 817, 892-893 Celotex Corporation, 1028-1029 Iron Fireman Mfg. Co., 990-991 General Insulating & Mfg. Co., L. J. Mueller Furnace Co., 824-825 1033 _ Meyer Furnace Co., 823 Insulite Company, The, 1036-1037 Herman Nelson Corp., 835 International Fibre Board. Ltd., Spencer Heater Division, 980-981 1039 __ Todd Combustion Equipment, Inc., United States Gypsum Co., 1049 PIPE ANCHORS American District Steam Co., 1000, -1014 E. B. Ba'dger & Sons Co., 1004,1017 Crane Company, 968-969 . Grinnell Co., Inc., 944-946, 1007 H. W. Porter & Co.. 1015 Ric-wiL Company, 1016 Underground Steam Construction Webster Engineering Co., 993 . Westinghouse Elec. & Mfg. Co., PERFORATED METALS Co., 1017 808-809.855 , . .. Williams Oil-O-Matic Heating Corp., 820 OIL BURNERS, Pressure Atom izing Todd Combustion Equipment, Inc., 994 " Auer Register Co., The, 896 Hendrick Mfg. Co., 900 Tuttle & Bailey, Inc., 902-903 U. S. Register Co., 904 Wickwire Spencer Steel Co., 906 PILLOW BLOCKS Lau Blower Co., 885 PIPE BENDING Baker Ice Machine Co., Inc., 866 Crane Company, 968-969 Frick Company, 869 Grinnell Co., Inc., 944-946, 1007 Arthur Harris & Co., 995 Parks-Cramer Co., 807 Vilter Manufacturing Co., 876 OIL BURNERS, Rotary Todd Combustion Equipment, Inc., 994 OIL BURNERS, Steam Atomiz ing Todd Combustion Eouipment, Inc., 994 " PIPE, Asbestos Eagle-Picher Lead Co;, 1032 Ehret Magnesia Mfg. Co., 1030 1031 Johns-Manville, 1040-1041 Standard Lime & Stone Co., 1048 PIPE, Brass Crane Co., 968-969 PIPE CONDUITS (See Conduits, Underground Pipe) PIPE COVERING (See Covering, Pipe) ^ PIPE FITTINGS (See Fittings, Pipe) Please mention THE GUIDE 1940 when writing to Advertisers 1080 INDEX TO MODERN EQUIPMENT PIPE GUIDES E. B. Badger & Sons Co.. 1004,1017 Crane Company, 968*969 H. W. Porter & Co.. 1015 Ric-wiL Company, The. 1916 Underground Steam Construction Co.. 1017 PIPE HANGERS (See Hangers, Pipe) PIPE SUPPORTS, For Under ground Conduit American District Steam Co., 1000. 1014 E. B. Badger & Sons Co., 1004,1017 Grinnell Co., Inc., 944-946, 1007 H. W. Porter & Co., 1015 Ric-wiL Company, The, 1016 Underground Steam Construction Co.. 1017 PITOT TUBES (See Air Measur ing and . Recording Instruments) PRECIPITATING EQUIPMENT Westinghouse Elec. & Mfe. Co.. 855 PRESSURE REDUCING VALVES (See Regulators, Pres sure) . PROPELLER FANS (See Fans. Propeller) PSYCHROMETERS (See also Air Measuring, Indicating and Re cording Instruments) American Moistening Co., 857 Bristol Company, The, 916 Juiien P. Fries & Sons, Div. of Bendix Aviation Corp., 917 Johnson Service Co., 922-923 Leeds & Northrup Co., 924 , Palmer Company, The, 929 Parks-Cramer Company, 807 Taylor Instrument Companies. 934 935 Westinghouse Elec. & Mfg. Co.. 808-809 Worthington Pump & Machinery Corp., 874-875 PUMPS. Brine Baker Ice Machine Co., 866 Buffalo Pumps, Inc., 996 Chicago Pump Co., 997 Frick Company, 869 Nash Engineering Co., 998-999 Trane Company, The, 838-839 Worthington Pump & Machinery Corp., 874-875 PUMPS, Centrifugal Bell and Gossett Co., 941 Buffalo Pumps, Inc., 996 Chicago Pump Co., 997 C. A. Dunham Co., 942-943 Frick Company, 869 . Nash Engineering Co., 998-999 Trane Company, The, 838-839 Worthington Pump & Machinery Corp., 874-875 PLASTER BASE, Fire Retarding PUBLICATIONS PUMPS, Circulating Armstrong Cork Company, 1025 Celotex Corporation, 1028-1029 Johns-Manville, 1040-1041 United States Gypsum Co., 1049 Air Conditioning--Oil Heat, 1054 Bell and Gossett Co., 941 American Artisan, 1056 -Buffalo Pumps, Inc., 996 American Society of Refrigerating Chicago Pump Co., 997 Engineers, 938 Crane Company, 968-969 . PLASTER BASE, Insulating Automatic Heat and Air Condi Minneapolis-HoneyweU Regulator tioning, 1059 Co., 926-927 Coal -Heat, 1055 . Nash Engineering Co., 998-999 Armstrong Cork Company, 1025 Celotex Corporation, 1028-1029 Genera] Insulating & Mfg. Co., 1033 Insulite Company, The, 1036-1037 International Fibre Board, Ltd.. 1039 Johns-Manville. 1040-1041 United States Gypsum Co., 1049 Wood Conversion Company, 1051 Domestic Engineering, 1058-1059 Fueloil Journal. 1060 Heating & Ventilating, 1061 Heating Journals, Inc., 1054 Heating, Piping and Air Condi tioning, 1057 Plumbing and Heating Trade Journal, 1062 Sheet Metal Worker, 1063 Trane Company, The. 838-839 PUMPS, Condensation American Radiator & Standard Sanitary Corp., 962-965 Buffalo Pumps, Inc, 996 Chicago Pump Co., 997 Crane Company, 968-969 C. A. Dunham Company, 942-943 PLASTER BASE, Sound Dead ening PULLEYS, Chain Hart & Cooley Mfg. Co., 898-899 United States Register Co., 904 Hoffman Specialty Co.. Inc., 948 949 Nash Engineering Co., 998-999 Trane Company, The, 838-839 Armstrong Cork Company, 1025 Barrett Company, 1026 Celotex Corporation, 1028-1029 PULLEYS, Speed Types Worthington Pump & Machinery Co., 874-875 General Insulating & Mfg. Co., 1033 Insulite Company, The, 1036-1037 International Fibre Board, Ltd., Lau Blower Co., 885 Westinghouse Elec. & Mfg. Co.. 808-809 PUMP MOTORS Electric) (See Motors. 1039 Johns-Manville. 1040-1041 United States Gypsum Co., 1049 Wood Conversion Company, 1051 PLATES, Iron PUMPS, Air and Gas Curtis Refrigerating Machine Co., Div. of Curtis Manufacturing Co., 868 Nash Engineering Co., 998-999 PUMPS, Steam Buffalo Pumps, Inc., 996 Trane Company, The, 838-839 Worthington Pump & Machinery Corp., 874-875 American Rolling Mill Co., 907 Carnegie-IHinois Steel Corp., 909 PUMPS, Sump PLATES, Stainless Steel American Rolling Mill Co., 907 Carnegie-IHinois Steel Corp., 909 PUMPS, Ammonia Worthington Pump & Machinery Corp., 874-875 York Ice Machinery Corp., 811 Buffalo Pumps, Inc., 996 Chicago Pump Co., 997 Nash Engineering Co., 998-999 PUMPS, Turbine . PLATES, Steel American Rolling MiU Co., 907 Carnegie-IHinois Steel Corp., 909 Jones & Laughlin Steel Corp., 910 PUMPS, Boiler Feed Buffalo Pumps, Inc., 996 Chicago Pump Co., 997 Nash Engineering Co., 998-999 Trane Company, The, 838-839 C. A. Dunham Co., 942-943 Hoffman Specialty Co.. Inc, 948 949 Nash Engineering Co., 998-999 Worthington Pump & Machinery Co.. 874-875 Numerals following ManufacturersT Names refer to pages in the Catalog Data Section 1081 ......HUS." HEATINC VENTILATINC AIR CONDITIONING CUIDE 1940 PUMPS, Vacuum General Electric Company, 816- RECEIVERS, Condensation Chicago Pump Co., 997 ' Curtis Refrigerating Machine Co., Div. of Curtis Manufacturing Company, 868 ` C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 . Nash Engineering Co., 998-999 PURGERS, Refrigeration 817.892-893 , Grinnel! Co., Inc., 944-946, 1007 Mario Coil Company, 871 'McQuay, Incorporated, 830-831 Modine Mfg. Co., 832-833 John J. Nesbitt, Inc., 836 ' Refrigeration Economics Co.,'837 B. F. Sturtevant Co., 886 Trane Company, The, 838*839 . Weil-McLain Company, 984 Young Radiator Company, 841 Baker Ice Machine Co., Inc., 866 Chicago Pump Co., 997 Crane Company. 968-969 ; C. A. Dunham Co., 942-943 ' Illinois Engineering Co., 950-951 Nash Engineering Co., 998-999 Sarco Company, Inc., 952-953 Trane Company, The, 838-839 Warren Webster & Co., 954-957 Westinghouse Elec. & Mfg. Co., 808-809,855 . Armstrong Machine Works, 1002 RADIATOR ENCLOSURES AND 1003 PYROMETERS, Portable and Stationary Bristol Company, The, 916 1 SHIELDS American Radiator & Standard Sanitary Corp., 962-965 Auer Register Co.. The, 896 Crane Company, 968-969 - Modine Mfg. Co., 832-833 RECEIVERS, Water Vapor American Blower C#fp., 802-803 Illinois Engineering Co., 950-951 Warren Webster & Co., 954-957 Illinois Testing Laboratories, Inc., 921 Leeds & Northrup Co., 924 Minneapolis-Honeywell Regulator H. J. Somers, Inc.. 850 United States Register Co., 904 Wickwire Spencer Steel Co., 906 RECORDERS, Humidity, Tem perature Co.. 926-927 Taylor Instrument Companies, 934 RADIATORS, Cabinet Bristol Company, The, 916 Julien P. Friez & Sons, Div. of 935 , American Radiator & Standard Bendix Aviation Corp.. 917 Sanitary Company, 962-965 - Johnson Service Co.. 922 Crane Company, 968-969 * Leeds & Northrop Co., 924 RADIATION, Aluminum 'C. A. Dunham Co., 942-943 Manning, Maxwell & Moore, Inc., Aerofin Corporation, 862-864 Mario Coil Company, 871 McQuay, Incorporated, 876 * J. J. Nesbitt, Inc., 836 Refrigeration Economics Co., 837 Trane Company, The, 838-839 Unit Heater and Cooler Co., 840 Warren Webster & Co., 954-957 Grinnell Co., Inc., 944-946, 1007 McQuay, Incorporated, 830-831 Modine Mfg. Co., 832-833 John J. Nesbitt, Inc., 836 Trane Company, The, 838-839 Unit Heater and Cooler Co., 840 Warren Webster & Co., 954-957 Weil-McLain Company, 984 Wickwire Spencer Steel Co., 906 925 . Minneapolis-Honeywell Regulator Co., 926-927 Powers Regulator Co., 930-931 Taylor Instrument Companies, 934 935 . Young Radiator Company, 841 REFRACTORIES, Cement, Ma RADIATION, Brass teriala Aerofin Corporation, 862-864 G & O Manufacturing Co., 865 . McQuay, Incorporated, 830-831 RADIATION, Cast-Iron American Radiator & Standard RADIATORS, Concealed American Radiator & Standard Sanitary Corp., 982-965 Burnham Boiler Corp., 967 Crane Company. 968-969 C. A. Dunham Co., 942-943 Grinnell Co., Inc., 944-946, 1007 Ilg Electric Ventilating Co., 884 Babcock 8t Wilcox Co., 966 Carey, Philip, Co., 1027 Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030- 1931 Johns-Manville, 1040-1041 Ric-wiL Company, 1016 Rubcroid Co., The, 1046-1047 Sanitary Corp.', 962-965 - McQuay, Incorporated, 830^831 * Burnham Boiler Corp., 967 Modine Mfg. Co., 832-833 Crane Company, 968-969 John J. Nesbitt, Inc., 836 Unit Heater and Cooler Co., 840. Trane Company. The, 838-839. United States Radiator Corp., 982 Unit Heater and Cooler Co., 840 REFRIGERATION CONTROLS (See also Controls) 983 United States Radiator Corp., 982 AIco Valve Company, 912 Weil-McLain Company, 984 983 .American Blower Corp., 802-803 Warren Webster & Co., 954-957 Barber-Colman Go., 897, 913 Weil-McLain Company, 984 Bristol Company, 916 ' RADIATION, Copper Young Radiator Company, 841 Cochrane Corp., 1005 Aerofin Corporation, 862-863 American Radiator & Standard Sanitary'Corp.. 962-965 C. A. Dunham Co., 942-943 G & O Manufacturing Co., 865 McQuay, Incorporated, 830-831 Modine Mfg. Co., 832-833 John J. Nesbitt, Inc., 836 Refrigeration Economics Co., 837 B. F. Sturtevant Co., 886 Trane Company, The, *838-839 Warren Webster & Co., 954-957. Young Radiator Company, 841 RECEIVERS, Air Baker Ice Machine Co., 866 Brownell Company, The, 985 Crane Company, 968-969 Curtis Refrigerating Machine Co., Div. Curtis Manufacturing Com pany, 868 Farrar & Trefts, Inc., 972 Illinois Engineering Co'., 950*951Kewanee Boiler Corp., 974-977 Parks-Cramer Company, 807 Warren Webster & Co., 954-957 Carrier Corporation, 804 . Detroit Lubricator Co., 914-915 Fedders Manufacturing Co., 828 Julien P. Frier & Sons, Div. of Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 Illinois Engineering Co., 950-951 Illinois Testing Laboratories, Inc., 921 Johnson Service Co., 922-923 . Leeds & Northrop Co., 924 . Manning, Maxwell & Moore, Inc., 925 Minneapolis-Honeywell Regulator Co., 926-927 RADIATION, Plain and Ex tended Surface Aerofin Corporation, 862-864 American Radiator & Standard Sanitary Corp., 962-965 Buffalo Forge Company. 881 G & O Manufacturing Co., 865 RECEIVERS, Ammonia Penn Electric Switch Co., 932. . Powers Regulator Co.,'930-931 Baker Ice Machine Co., 866 Carbondale Div., Worthington Pump & Machinery Corp., 874 875 Frick Company, 869 York Ice Machinery Corp., 811 Sarco Company, Inc., 952-953 " Taylor Instrument Companies, 934 935 Westinghouse Elec. & Mfg. Co., 808-809,855 White-Rodgers Elec. Co., 937 . Please mention THE GUIDE 1940 when writing to Advertisers 1082 INDEX TO MODERN EQUIPMENT IV. l!: REFRIGERATING EQUIPMENT, Centrifugal Carrier Corporation, 804 Trane Company, The, 838-839 Worthington Pump & Machinery Co., 874-875 York Ice Machinery Corp., 811 Minneapolis-Honeywell Regulator Co.. 926-927 Tuttle & Bailey, Inc., 902-903 United States Register Co., 904 REGULATORS, Damper American Radiator & Standard REGULATORS, Humidity (See Humidity Control) REGULATORS, Pressure . American Radiator & Standard Sanitary Corp., 962-965 Binks Manufacturing Co., 858-859 Sanitary Corp.. 962-965 Bristol Company, The, 916 REFRIGERATING EQUIPMENT, Steam Jet Barber-Colman Co., 897, 913 Barnes & Jones, Inc., 940 Detroit Lubricator Co., 914-915 Crane Company. 968-969 Detroit Lubricator Co., 914-915 C. A. Dunham Co., 942-943 ' American Blower Corp.T&02-803 . Julien P. Frie*. & Sons, Div. of Fedders Manufacturing Co., 828 Carbondale Div., Worthington Bendix Aviation Corp., 917 Julien P. Frie? & Sons, Div. of Pump & Machinery Corp-, 874- Fulton Sylphon Co., 918-919 Bendix Aviation Corp., 917 875 General Electric Company, 816- Fulton Slyphon Co., 918 Carrier Corporation, 804 Universal Cooler Corp., 873 WpVrinehouse * Elec ' & Mfc "o8n0o8-w80io9, 855 * ' Co . ` ,, 892-893 WilliamJ>. Haines & Co., 947 - Hart & Cooley Mfg. Co., 898-899 Henry Furnace & Foundry Co., 822 General Electric Company, 816- 817,892-893 y Henry Furnace & Foundry Co., 822 Illinois Engineering Co., 950-951 Hoffman Specialty Co., Inc., 948- Jenkins Bros., 1008 949 Kieley & Mueller, Inc., 1009 REFRIGERATING MACHINERY Illinois Engineering Co., 950-951 Johnson Service Co., 922-923 Minneapolis-Honeywell Regulator Co., 926-927 . Kieley & Mueller, Inc., 1009 Airtemp Div., Chrysler Corp., 812- Leeds & Northrup Co., 924 Mueller Steam Specialty Co., Iric., 1010 813 Baker Ice Machine CoM 866 Manning, Maxwell & Moore, Inc., Penn Electric Switch Co.. 932 . 925 ` .' Powers Regulator Co., 930-931 Brunner Manufacturing Co., 867 Minneapolis-Honeywell Regulator Spence Engineering Co., 933 Carbondale Div., Worthington Co., 926-927 Taylor Instrument Companies, 934- Pump & Machinery Corp., 874- Penn Electric Switch Co., 932. 875 Powers Regulator Co., 930-931 Carrier Corporation, 804 . Sarco Company, Inc., 952-953 Curtis Refrigerating Machine Co., Spence Engineering Co., 933 935 ' ' Warren Webster & Co., 954-957 White-Rodgers Elec. Co., 937 Div. of Curtis Manufacturing Taylor Instrument Companies, 934- Company, 868 935 - REGULATORS* Temperature Frick Company, 869 . Trane Company, The, 838-839 General Electric Company, 816- Tuttle & Bailey, Inc., 902-903 (See Temperature Control) 817,892-893 United States Register Co., 904 General Refrigeration Corp., 870 Refrigeration Economics Co., 837 Serve!, Inc., 872 Trane Company, The, 838-839 Universal Cooler Corp., 873 Warren Webster & Co^, 954-957 Webster Engineering Co., 993 Whtte-Rodgers Elec. Co.. 937 Young Radiator Co., 841 .. RELIEF VALVES (See Valves, Relief) RUST AND SCALE REMOVER. Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co., REGULATORS, Feed Water Oakite Products, Inc., 856 wfufkTM' CK? O M.tir Kie|ey & Mueller. Inc., 1009 Coraiuon 820 Heating McDonnell & Miller. 900-961 SAFETY VALVES (See Valves, Safety) York*!^ Machinery Corp., 811 MueOer Steam Specialty Co., Inc.. . Powers Regulator Co., 930-931 SCREENS, Window Insulation REGISTERS <See Cro Grilles. Registers, etc.) 808-809, 855 Co . Ingersoll Steel & Disc Div., BorgWarner Corp., 1022 , . * American Blower Corp., 802-803. Wright-Austin Co., 1011 . American Coolair Corp., 878-879.. SEALS, Inside Door Bottoms Anemostat Corp. of America, 895 Auer Register Co., The, 896 Barber-Colman Co., 897. 913 H|98S9C900leyManUfaCtUringCO' REGULATORS, Furnace Barber-Colman Co., 897, 913 Futoi'sdKr'A^15 Chamberlin Metal Weather Strip Co., 1018-1019 SEATS, Flexible Pipe Line 898-899 Hendrick Mfg. Co., 900 Fulton Sylphon Co., 918-919 _ 0 D . ,,_ _ Hart & Cooley Mfg. Co., 898-899 Badger & Sons Co., 1004,1017 Independ-e--n--t---R---e-g-i-s--t-e--r--Co,.,--901 Henry Furnace & Foundry Co., 822 L. J. Mueller Furnace Co., 824-825 Minneapolis-Honeywell Regulator SEPARATORS Dust Trane Company, The, 838-839 Co., 926-927 oc-rAiuuuiw.uugt Tuttle & Bailey, Inc.', 902-903 United States Air Conditioning Corp., 810 United States Register Co., 904 Waterloo Register Go., 905 Penn Electric Switch Co., 932 Spence Engineering Co., 933 Tuttle & Bailey, Inc., 902-903 White-Rodgers Elec. Co., 937 Air-Maze Corp., 844-845' American Air Filter Co., 846-847 American Blower Corp., 802-803 Buffalo Forge Company. 881 Coppus Engineering Corp.;-848 Wickwire Spencer Steel Co., 906 Staynew Filter Corp., 852-853 . REGULATORS, Gas B. F. Sturtevant Co., 886 REGISTERS, Oil Burning Todd Combustion Equipment. Inc A. _ _ American Radiator & Standard Sanitary Corp., 962-965 Barber Gas Burner Go., 992 Unit Heater and Cooler Co., 840 Westinghouse Elec. & Mfg. Co. 808-809, 855 994 ' Crane nC-o--m---p--any , 968-969 Detroit Lubricator Co., 914-915 SEPARATORS, Oil REGULATORS, Air Volume Anemostat Corp. of America, 895 Barber-Colman Co., 897, 913 Hart & Cooley Mfg. Co., 898-899 Jenkins Bros.. 1008 Air-Maze Corp., 844-845 Mercoid Corp.. 928 C----o-c--h--r-a--n- e- Corp., s1m0m05v Minneapolis-Honeywell Regulator Crane Company, 968-969 Co., 926-927 ' Frick Company, 869 Penn Electric Switch Co., 932 Henry Valve Company, 920 ' White-Rodgers Elec. Co., 937 Kieley & Mueller, Inc., 1009 Numerals following Manufacturers' Names refer to pages In the Catalog Data Section 1083 !f3T HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Staynew Filter Corp., 8---------Warren Webster & Co., 954-957 SMOKE DENSITY RECORDING STOKERS. Mechanical, Anthracite Worthington Pump & Machinery Bristol Company, The. 916 Babcock & Wilcox Co., 966 Co., 874-875 Leeds & Northrup Co., 924 Combustion Engineering Co., 988 Wright-Austin Co., 1011 Westinghouse Elec. & Mfg. Co., Crane Company, 968-969 SEPARATORS, Steam Cochrane Corp., 1005 808-809, 855 SOOT DESTROYER Iron Fireman Mfg. Co., 990-991 MotorStoker Division Hershey Ma chine & Fdy Co., 989 Crane Company, 968-969 Kieley & Mueller, Inc., 1009 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 SHEETS, Aluminum Foil Aluminum Aircell Insulation Co., 1023 Ruberoid Co., The. 1046-1047 SHEETS, Asbestos, Flat and Corrugated Carey, Philip, Co., 1027 Ehret Magnesia Mfg. Co., 1030 1031 Johns-Manville, 1040-1041 Ruberoid Co., The, 1046-1047 Vinco Company, Inc., 958-959 SOUND DEADENING, Insula tion Aluminum Aircell Insulation Corp., 1023 American Hair & Felt Co., 1024 Armstrong Cork Company, 1025 Celotex Corporation, The, 1028 1029 Eagle-Picher Lead Co., 1032 Ehret Magnesia Mfg. Co., 1030 1031 Insuliie Company, The, 1036-1037 International Fibre Board, Ltd., 1039 Johns-Manville, 1040-1041 Kimberly-Clark Corp., 1042-1043 STOKERS, Mechanical, Bituminous . Babcock & Wilcox Co.. 966 : Brownell CompanyHl85 Combustion Engineering Co., 988 Crane Company, 968-969 Delco Appliance Div., General Motors Sales Corp., 814-815 Detroit Stoker Co., 986-987 Iron Fireman Mfg. Co., 990-991 Meyer Furnace Company, 823 Pocahontas Fuel Co., 826 STOKER MOTORS (See Motors, Electric) STRAINERS, Dirt SHEETS, Black Galvanized Mundet Cork Corp., 1044 Pacific Lumber Co., The, 1045 Barnes & Jones, Inc., 940 Crane Company, 968-969 ' American Rolling Mill Co., 907 Carnegie-Illinois Steel Corp., 909 Jones & Laughlin Steel Corp.. 910 Ruberoid Co., The, 1046-1047 C. A. Dunham Co., 942-943 Standard Lime & Stone Co., 1048 Grinnell Co., Inc., 944-946, 1007 United States Gypsum Co., 1049 Henry Valve Company, 920 Western Felt Works, 1050 ' Hoffman Specialty Co., Inc., 948 ' SHEETS, Copper Alloy Wood Conversion Co., 1051 949 Mueller Steam Specialty Co., Inc., Camegie-Illinois Steel Corp., 909 SHEETS, Copper Bearing Steel American Rolling Mill Co., 907 Bethlehem Steel Co., 908 SPRAY EQUIPMENT Binks Manufacturing Co., 858-859 Unit Heater & Cooler Co., 840 Martocello, Jos. A. & Co., 861 Yarnall-Waring Co., 1012 1010 Sarco Company, Inc., 952-953 Spence Engineering Co.. 933 Trane Company, The, 838-839 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 Camegie-Illinois Steel Corp., 909 Jones & Laughlin Steel Corp., 910 SHEETS. Felt Western Felt Works, 1050 SHEETS, Pure Iron American Rolling Mill Co., 907 SHEETS, Special Finish American Rolling Mill Co., 907 Bethlehem Steel Co., 908 Carnegie-Illinois Steel Corp., 909 SPRAY NOZZLES American Blower Corp., 802-803 Baker Ice Machine Co., 866 Bayley Blower Company, 880 Binks Manufacturing Co.,' 858-859 Buffalo Forge Company, 881 Clarage Fan Company, 805 Marley Co., The, 871 Martocello, Jos. A. & Co., 861 Niagara Blower Company, 806 Parks-Cramer Co., 807 B. F. Sturtevant Co.. 886 Trane Company, The, 838-839 _ Westinghouse Elec. & Mfg. Co.', 808-809, 855 STRAINERS, Oil Crane Company, 968-969 Detroit Lubricator Co., 914-915 General Electric Company, 816 817, 892-893 Kieley & Mueller, Inc., 1009 Mueller Steam Specialty Co., Inc., 1010 . Sarco Company, Inc., 952-953 Spence Engineering Co., 933 Staynew Filter Corp., 852-853 Todd Combustion Equipment, Inc., 994 Wright-Austin Co., 1011 SHEETS, Stainless Steel American Rolling Mill Co., 907 Yarnall-Waring Co., 1012 York Ice Machinery Corp., 811 - STRAINERS, Refrigerant Camegie-Illinois Steel Corp., 909 SHEETS, Steel . American Rolling Mill Co., 907 Bethelehem Steel Co., 908 Camegie-Illinois Steel Corp., 909 Jones & Laughlin Steel Corp.. 910 SHUTTERS, Automatic American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 Barber-Colman Co., 897, 913 Champion Blower & Forge Co., 882 Ilg Electric Ventilating Co., 884 Minneapolis-Honeywell Regulator SPRAY NOZZLE COOLING SYSTEM American Blower Corp., 802-803 Baker Ice Machine Co., 866 Bayley Blower Co., 880 ' ' ' Binks Manufacturing Co., 858-859 Buffalo Forge Co., 881 Clarage Fan Company, 805 Marley Company, 860 ' Niagara Blower Company, 806 B. F. Sturtevant Co., 886 Trane Company, The, 838-839 Yarnall-Waring Co., 1012 York Ice Machinery Corp., 811 Alco Valve Company. 912 Henry Valve Company, 920 STRAINERS. Steam Crane Company, 968-969 Detroit Lubricator Co., 914-915 Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 Mueller Steam Specialty Co., Inc., 1010 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 Trane Company, The, 838-839 Wright-Austin Co., 1011 Co., 926-927 B. F. Sturtevant Co., 886 L. J. Wing Mfg. Co., 890-891 STACKS, Steel Bethlehem Steel Co., 908 Brownell Co., 985 STRAINERS, Water Crane Company, 968-969 Hendrick Mfg. Co., 900 Detroit Lubricator Co'., 914-915 SLIME PREVENTION (See also Illinois Engineering Co., 950-951 Algae Prevention) STEAM HEATING SYSTEMS Kieley & Mueller, Inc., 1009 Oakite Products, Inc., 856 (See Heating Systems, Steam) . McDonnell & Miller, 960-961 Please mention THE GUIDE 1940 when writing to Advertisers 1084 INDEX TO MODERN EQUIPMENT Mueller Steam Specialty Co., Inc., White-Rodgers Elec. Co.. 937 1010 L. J. Wing Mfg. Co., 890-891 Powers Regulator Co., 930-931 Yarnall-Waring Co., 1012 TOWERS, Cooling (See Cooling Towers) Sarco Company, Inc., 952-953 ' Spence Engineering Co., 933 Staynew Company, Inc., 952-953 Wright-Austin Co., 1011 THERMOMETERS, Distance Type TRANSFORMERS - General Electric Company, 816 817, 892-893 Yarnall-Waring Co., 1012 Bristol Company, The, 916 Wagner Electric Corp., 894 Julien P. Fries & .Sons, Div. of TANK COILS (See Coils, tank) TANK COVERING (See Covering, Pipes and Surfaces) TANK HEATERS (See Heaters, Tank) TANKS, Blow-off Brownell Company, The, 985 Farrar & Trefts, Inc., 972 Kewanee Boiler Corp., 974-977 Bendix Aviation Corp., 917 Illinois Testing Laboratories, Inc., 921 Johnson Service Co., 922:923 Leeds & Northrop Co., 924 " Manning, Maxwell & Moore, Inc., 925 Minneapolis-Honeywell Regulator Co., 926-927 Palmer Company, 929 Powers Regulator Co.. 930-931 Sarco Co., Inc., 952-953 Taylor Instrument Companies, 934 935 TRAPS, Bucket Armstrong Machine Works, 1002 1003 Cochrane Corp., 1005 Crane Company, 968-969 C. A. Dunham Co., 942-943 Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 Mueller Steam Specialty Co., Inc., 1010 Sarco Company, Inc., 952-953 Trane Company, The, 838-839 Wright-Austin Co., 1011 TANKS, Pressure Baker Ice Machine Co., 866 Bell and Gossett Co., 941 Bethlehem Steel Co., 908 Binks Manufacturing Co., 858-859 Brownell Company, The, 985 Burnham Boiler Corp., 967 Farrar & Trefts, Inc., 972 Frick Company, 869 Kewanee Boiler Corp., 974-977 TANKS, Storage American Radiator & Standard Sanitary Corp., 962-965 E. B. Badger & Sons Co., 1004,1017 Bethlehem Steel Co.. 908 Brownell Company, The, 985 Burnham Boiler Corp., 967 Farrar & Trefts, Inc., 972 United States Gauge Co., 936 THERMOMETERS, Indicating Bell and Gossett Co., 941 Bristol Company, The, 916 Julien P. Frie* & Sons, Div. of Bendix Aviation Corp., 917 Illinois Testing Laboratories. Inc., 921 . Johnson Service Co., 922-923 Leeds & Northrup Co., 924 Martocello, Jos. A. & Co.. 861 M inneapolis- Honeywell Regulator Co.. 926-927 Palmer Company, The, 929 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Taylor Instrument Companies, 934 935 United States Gauge Co., 936 TRAPS, Float American District Steam Co., 1000, 1014 Armstrong Machine Works, 1002 1003 Barnes & Jones, Inc., 940 Crane Company. 968-969 C. A. Dunham Co., 942-943 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 Mueller Steam Specialty Co., Inc., 1010 Sarco Company, Inc., 952-953 Trane Company, The, 838-839 Warren Webster & Co.. 954-957 Wright-Austin Co., 1011 TRAPS, Float and Thermostatic Frick Company, 869 Kewanee Boiler Corp., 974-977 THERMOMETERS, Recording American District Steam Co., 1000, 1014 Bristol Company, The, 916 Armstrong Machine Works, 1002 TEMPERATURE CONTROL Julien P. Frier & Sons, Div. of 1003 Bendix Aviation Corp., 917 Barnes & Jones,' Inc., 940 American Radiator & Standard Leeds & Northrup Co., 924 C. A. Dunham Co., 942-943 Sanitary Corp., 962-965 Barber-Colman Co., 897, 913 Manning, Maxwell & Moore, Inc., 925 Grinnell Co.. Inc., 944-946, 1007 William S. Haines & Co., 947 Barnes & Jones, Inc., 940 Palmer Company, 929 Hoffman Specialty Co., Inc., 948 Bristol Company, The, 916 Powers Regulator Co., 930-931 949 Cochrane Corp., 1005 Crane Compahy, 968-969 Taylor Instrument Companies, 934 935 Illinois Engineering Co., 950-951 Mueller Steam Specialty Co.. Inc., Delco Appliance Div., General United States Gauge Co., 936 1010 Motors Sales Corp., 814-815 Powers Regulator Co., 930-931 Detroit Lubricator Co., 914-915 THERMOSTATS Sarco Company, Inc., 952-953 C. A. Dunham Co., 942-943 Julien P. Friez & Sons, Div. 6f Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 General Electric Company, 816 817, 892-893 Illinois Engineering Co., 950-951 Illinois Testing Laboratories, Inc., 921 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 Leeds & Northrop Co., 924 . Manning, Maxwell & Moore, Inc.. 925 Mercoid Corporation, The, 928 Minneapolis-Honeywell 'Regulator Co., 926-927 Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 Taylor Instrument Companies, 934 American Radiator & Standard Sanitary Corp., 962-965 Barber-Colman Co.. 897. 913 Crane Company, 968-969 . Detroit Lubricator Co.. 914-915 Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 General Electric Company, 816 817, 892-893 Illinois Engineering Co., 950-951 Johnson Service Co., 922-923 Manning, Maxwell & Moore, Inc., 925 . Mercoid Corporation, The, 928 Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 White-Rodgers Elec. Co., 937 Trane Company, The, 838-839 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 TRAPS, Radiator Armstrong Machine Works, 1002 1003 Barnes & Jones, Inc., 940 C. A. Dunham Co., 942-943 ,William S. Haines & Co., 947 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Sarco Company, Inc., 952-953 Trane Company. The, 838-839 Warren Webster & Co., 954-957 TRAPS, Return Barnes & Jones, Inc., 940 Crane Company, 968-969 C. A. Dunham Co.. 942-943 935 Trane Company, The, 838-839 TIN PLATE William S. Haines & Co., 947 Hoffman Specialty Co., Inc., 948 Warren Webster & Co., 954-957 Carnegie-Illinois Steel Corp., 909 949 Numerals following Manufacturers' Names refer to pages In the Catalog Data Section 1085 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Illinois Engineering Co., 950-951 TUBING, Flexible Metallic (See VALVES, Automatic Kieley & Mueller, Inc., 1009 . also Conduit, flexible; Hose, flexi- Alco Valve Company, Inc.. 912 Mueller Steam Specialty Co., Inc., ble) . American Radiator & Standard 1010 American Radiator & Standard Sanitary Corp., 962-965 -Sarco Company. Inc., 952-953 Sanitary Corp., 962-965 Anderson Products, Inc., 1001 ' Trane Company, The, 838-839 Baker Ice Machine Co., 866 .Warren Webster & Co., 954-957 TRAPS, Scale Henry Valve Company, 920 TUBING, Steel Babcock & Wilcox Co., 966 Bethlehem Steel Co., 908 Jones & Laughlin Steel Corp., 910 Barber-Colman Co., 897, 913 Crane Company, 968-969 Bristol Company, The, 916 Detroit Lubricator Co., 914-915 Dole Valve Company, 1006 . ' * Fedders Manufacturing Co., 828 . TRAPS, Steam American District Steam Co., 1000, 1014 Armstrong Machine Works, 1002 1003 Barnes & Jones, Inc., 940 Cochrane Corp., 1005 Crane Company, 968-969 C. A. Dunham Co., 942-943 .Grinnell Co., Inc., 944-946. 1007 William S. Haines & Co., 947 Hoffman Specialty Co., Inc., 948 949 Illinois Engineering Co., 950-951 Kieley & Mueller, Inc.. 1009 TURBINES Coppus Engineering'Gorp., 848 B. F. Sturtevant Co., 886 Westinghouse Elec. & Mfg. Co., 808-809, 855 L. J. Wing Mfg. Co., 890-891 UNDERGROUND PIPE CON ' DUITS (See Conduits, Under ground Pipe) UNIT HEATERS (See Healers, Unit) Frick Company, 869 Julien P. Fries & Sons, Div. of Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 ' Manning, Maxwell & Moore, Inc., 925 ' Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co., 933 Trane Company, The, 838-839 Mueller Steam Specialty Co., Inc., 1010 Sarco Company, Inc., 952-953 Powers Regulator Co., 930-931 UNIT VENTILATORS (See Venti lators, Unit) VALVES, Back Pressure Baker Ice Machine Co., 866 Cochrane Corp.. 1005 Trane Company, The. 838-839 Crane Company, 968-969 ' Warren Webster & Co., 954-957 UNITS, Air Conditioning (See Illinois Engineering Co.,'950-951 Wright-Austin Co., 1011 . Air Conditioning Units) Jenkins Bros., 1008 .Yarnall-Waring Co., 1012 l Kieley & Mueller, Inc., 1009 TRAPS, Thermostatic . V-BELT DRIVES American Coolair Corp., 878-879 Mueller Steam Specialty Co., 1010 Spence Engineering Co., 933 Taylor Instrument Companies, 934 Barnes & Jones, Inc., 940 C. A. Dunham Co., 942-943 Frick Company, 869 935 Worthington Pump & Machinery York Ice Machinery Corp., 811 Grinnell Co., Inc., 944-946, 1007 Corp., 874-875 William S. Haines & Co., 947 VALVES, Balanced Hoffman Specialty Co., Inc., 948 . 949 - Illinois Engineering Co., 950-951 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Trane Company, The, 838-839 Warren Webster & Co., 954-957 VACUUM HEATING SYSTEMS (See Heating Systems, Vacuum) Crane Company, 968-969 Illinois Engineering Co., 950-951 Jenkins Bros., 1008 ,>. .Kieley & Mueller, Inc., 1009 VALVES, Air Mueller Steam Specialty Co., 1010 American Radiator & Standard Spence Engineering Co., 933 Sanitary Corp., 962-965 TRAPS, Vacuum Anderson Products, Inc., 1001 Armstrong Machine Works; 1002 1003 Barnes & Jones, Inc., 940 "C. A. Dunham Co., 942-943 . .William S. Haines & Co., 947 / Hoffman Specialty Co., Inc., 948 Bristol Company, The, 916 Burnham Boiler Corp., 967 Crane Company, 968-969 Curtis Refrigerating. Machine Co., Div. of Curtis Manufacturing Company, 868 ' Detroit Lubricator Co., 914-915 . 949 Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 , Mueller Steam Specialty Co., Inc., 1010 Sarco Company, Inc., 952-953 - Trane Company, The, 838-839 Warren Webster & Co., 954-957 Wright-Austin Co., 1011 Dole Valve Company, 1006 . Hoffman Specialty Co., Inc., 948 949 Jenkins Bros., 1008 Kieley & Mueller, Inc., 1009 Manning, Maxwell & Moore, Inc., 925 . Spence Engineering Co., 933 Trane Company, The, 838-839 TUBE CLEANERS Wright-Austin Co., 1011 VALVES, Blow-off Cochrane Corp., 1005 Crane Company. 968-969 ' Detroit Lubricator Co., 914-915 Henry Valve Company, 920 Jenkins Bros., 1008 \- Kieley & Mueller, Inc., 1009 * Manning, Maxwell & Moore, Inc., 925 McDonnell & Miller, 960-961 . Yarnall-Waring Co., 1012 . VALVES, By-Pass '. Crane Company, 968-969 Henry Valve Company, 920 Jenkins Bros., 1008 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 Manning, Maxwell & Moore, Inc., . Martocello, Jos. A. & Sons, 861 VALVES, Angle, Globe and 925 TUBES. Boiler Babcock & Wilcox Co., 966 Bethlehem Steel Co., 908 ' Camegie-lllinois Steel Corp., 909 . Jones & Laughlin Steel Corp., 910 TUBES, Pitot (See Air Measuring Cross Baker Ice Machine Co., 866 Burnham Boiler Corp., 967 Carbondale Div., Worthihgton Pump & Machinery Co., 874 875 Crane Company, 968-969 Detroit Lubricator Co., 914-915 VALVES, Check Cochrane Corp., 1005 : Crane Company, 968-969 . Fedders Manufacturing Co., 828 Frick Company, 869 Grinnell Co., Inc., 944-946, 1007 Henry Valve Company, 920 Illinois Engineering Co., 950-951 and Recording Instruments) , Frick Company, 869 Grinnell Co.. Inc., 944-946, 1007 Jenkins Bros.. 1008 Manning, Maxwell & Moore,- Inc., TUBING, Fabricated Bethlehem Steel Co., 908 Arthur Harris & Co., 995 Henry Valve Company; 920 . Jenkins Bros., 1008 . - York Ice Machinery Corp., 811 925 Warren Webster & Co., 954-957 York Ice Machinery Corp., 811 Please mention THE GUIDE 1940 when writing ot Advertisers 1086 INDEX TO MODERN EQUIPMENT VALVES, Diaphragm VALVES, Magnetic ^ Jenkins Bros., 1008 Alco Valve Company, 912 Illinois Engineering Co., 950-951 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 . Alco Valve Company, Inc., 912 Barber-Colman Co., 897, 913 : Detroit Lubricator Co., 914-915 Frick Company, 869 Minneap>olis-IIoneywell Regulator Co., 926-927 Sarco Company, Inc., 952-953 Manning, Maxwell & Moore, Inc,, 925 Mueller Steam Specialty Co., 1010 Powers Regulator Co., 930-931 Taylor Instrument Companies, 934 935 ' VALVES, Expansion . Alco Valve Company, Inc., 912 Crane Company. 968*969 Detroit Lubricator Co., 914-915 Fedders Manufacturing Co., 828 Frick Company, 869 Fulton Sylphon Co., 918-919 Henry Valve Company, 920 . Spence Engineering Co., 933 York Ice Machinery Corp., 811 VALVES, Float. Julien P. Frier & Sons. Div. of VALVES, Radiator Orifice Bendix Aviation Corp., 917 Ge0n1e7rafliQOELSleQcQtric Company. ' . 816-' American District Steam Co., 1000. 1014 McDonnell & Miller, 960-961 ,- American Radiator & Standard Sanitary Corp., 962-965 Minneapolis-Honeywell Regulator Co., 926-927 Penn Electric Switch Cor, 932 Spence Engineering Co., 933' Barnes & Jones, Inc., 940 . Detroit Lubricator Co., 914-915 C. A. Dunham Co., 942-943 Grinnell Co., Inc., 944-946, 1007 VALVES, Mixing, Thermostatic William S. Haines & Co., 947 Hoffman Specialty Co., Inc., 948 Barber-Colman Co., 897, 913 949 . Dole Valve Company, 1006 Illinois Engineering Co., 950-951 Fulton Sylphon Co., 918-919 Sarco Company, Inc., 952-953 Johnson Service Co., 922-923 Trane Company, The, 838-839. Minneapolis-Honeywell Regulator Warren Webster & Co., 954-957 Co., 926-927 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 VALVES, Radiator, Pneumatic Diaphragm Alco Valve Company, Inc,, 912 Anderson Products. Inc., 1001 Baker Ice Machine Co., 866 Cochrane Corp., 1005 >, Crane Company, 968-969 `VALVES, Non-Return Crane Company, 968-969 - Fedders Manufacturing Co., 828 Frick Company, 869 Bell and Gossett Co.,.941 Bristol Company, The, 916 Johnson Service Co., 922-923 ' Minneapolis-Honeywell Regulator Co., 926-927 Detroit Lubricator Co., 914-915 ' Dole Valve Company, 1006 Frick Company, 869 General Electric Company, 816 817, 892-893 Illinois Engineering Co., 950-951 Jenkins Bros., 1008 Kieley & Mueller, Inc., 1009 Manning, Maxwell & Moore, Inc., 925 Powers Regulator Co., 930-931 Taylor Instrument Companies, 934 935 VALVES, Refrigerant Line ' Illinois Engineering Co., 950-951 ' Kieley & Mueller, Inc., 1009 \ VALVES, Packless Refrigerant Henry Valve Company, 920 McDonnell & Miller, 960-961 Mueller Steam Specialty Co., 1010 Sp>ence Engineering Co., 933 Trane Company, The. 838-839 York Ice Machinery Corp., 811 VALVES, Flow Control Bell & Gossett Co., 941 Bristol Company, The, 916 Henry Valve Company, 920 VALVES, Pressure Reducing (See Regulators, Pressure) VALVES, Pump Crane Company, 968-969 . Jenkins Bros., 1008 Trane Company, The, 838 . VALVES, Relief Baker Ice Machine Co., 866 Bell and Gossett Co., 941 Cochrane Corp., 1005 . Crane Company, 968-969 Frick Company, 869 . ' " Henry Valve Company, 920 . . Illinois Engineering Co., 950-951 Kieley & Mueller, Inc., 1009 ... Crane Company, 968-969 C. A. Dunham Co., 942-943 Frick Company, 869 * VALVES, Purge Henry Valve Company, 920 Manning, Maxwell & Moore, Inc., 925 Mueller Steam Sp>ecialty Co., Inc.. General Electric Company, 816 817,892-893 VALVES, Radiator 1010 Trane Company, The, 838-839 Hoffman Sp>ecialty Co., Inc.; 948 American District Steam Co..1000. York Ice Machinery Corp., 811 : 949 : 1014 Illinois Engineering Co., 950-951 American Radiator & Standard Kieley & Mueller, Inc., 1009 Sanitary Corp., 962-965 Manning, Maxwell & Moore, Inc.; Anderson Products, Inc., 1001 925 Barnes & Jones, Inc., 940 ' McDonnell & Miller, 960-961 Bell and Gossett Co., 941 Minneapolis-Honeywell Regulator Burnham Boiler Corp., 967 Co., 926-927 Crane Company, 968-969 ' ` Mueller Steam Specialty Co., Inc., Detroit Lubricator Co., 914-915 1010 Dole Valve Company, 1006 Powers Regulator Co., 930-931 C. A. Dunham Co., 942-943 Spence Engineering Co:. 933 Fulton Sylphon Co., 918-919 Taylor Instrument Companies, 934 Grinnell Co.. Inc., 944-946, 1007 935 . 'William S. Haines & Co., 947 VALVES. Safety ; American Radiator & Standard Sanitary Corp., 962-965 Baker Ice Machine Co., 866 . Crane Company, 968-969 v Detroit Lubricator Co., 914-915 Frick Company, 869 . . Henry Valve Company, 920 Jenkins Bros., 1008 Manning, Maxwell & Moore, Inc.,- 925 * Sp>ence Engineering Co., 933 . Warren Webster & Co., 954-957 Hoffman Specialty Co., Inc., 948r 949 VALVES, Gate Crane Company, 968-969 Detroit Lubricator Co., 914-915 Grinnell Co.. Inc.. 944-946, 1007 Jenkins Bros., 1008 - Illinois Engineering Co., 950-951 Jenkins Bros., 1008 - Sarco Company. Inc., 952-953 Trane Company, The, 838-839 Warren Webster & Co., 954-957 Manning, Maxwell & Moore, Inc., VALVES, Radiator, Electric 925 Motor Operated VALVES, Solenoid Alco Valve Company, Inc., 912 Anderson Products, Inc., 1001. Barber-Colman Co., 897, 913 . Detroit Lubricator Co., 914-915 Frick Company, 869 Julien P. Friez & Sons, Div. of . Bendix Aviation Corp., 917 ' Fulton Sylphon Co., 918-919 General Electric Company, 816 VALVES, Hydraulic Barber-Colman Co.. 897, 913 Bristol Company, The, 916 Crane Company, 968-969 Julien P. Friez & Sons, Div. of Jenkins Bros., 1008 ' Bendix Aviation Corp., 917 Manning, Maxwell & Moore, Inc., Fulton Sylphon Co., 918 925 General Electric Company, 816 Yarnall-Waring Co., 1012 817, 892-893 817,892-893 . McDonnell & Miller, 960-961 - ' '. Minneapolis-Honeywell -Regulator Co.. 926-927 . Penn Electric Switch Co., 932 Spence Engineering Co., 933 . Trane Company, The, 838-839* T Numerals following Manufacturers' Names refer to pages in the Catalog Data Section 1087 ' HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 VALVES, Stop and Check {See Aneraostat Coin, of American, 895 CarbondateDiv.. Worthington Valves, Non-Return) Auer Register Co., The, 896 Pu^mp & Machiney Corp., 874- Barber-Colman Co., 897, 913 VALVES, Thermostatic Coppus Engineering Corp., 848 AIco Valve Company, Inc.. 912 Barber-Cotman Co., 897. 913 Barnes & Jones, Inc., 940 Detroit Lubricator Co.. 914-915. Fedders Manufacturing Co.. 828 Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 Fulton Sylphon Co., 918-919 Hart & Cooley Mfg. Co., 898-899 Hendrick Mfg. Co., 900 Independent Register Co., 901 L. J. Mueller Furnace Co., 824-825 B. F. Sturtevant & Co., 886 Tuttle & Bailey. Inc., 902-903 UnitedStates Register Co., 904 Waterloo Register Co., 905 General Electric Company, 816 817. 892-893 VENTILATORS, Mushroom Grinnell Co., Inc., 944-946, 1007 American Blower Corp., 802-803 Illinois Engineering Co., 950-951 Clarage Fan Company, 805 Johnson Service Co., 922-923 Coppus Engineering Co., 848 Manning, Maxwell & Moore, Inc., L. J. Mueller Furnace Co., 824-825 925 Tuttle & Bailey, Inc., 902-903 Minneapolis-Honeywell Regulator Carrier Corporation, 804 Curtis Refrigerating Machine Co Div. of Curtis Manufacturing Company, 868 Fedders Manufacturing Co. 828 * Frick Company, 869 ' General Refrigeration Corp. 870 Marley Co., Inc., 860 ' '*'* McQuay, Incorporated. 830-831 Refrigeration Economics Co 837 Servel. Inc., 872 - Trane Company, The, 838-839 Universal Cooler Corp., 873 ' Vilter Manufacturing Co., 876 Westinghouse Elec. & Mfg. Co 808-809,855 v York Ice Machinery Corp., 811 Co.. 926-927 Penn Electric Switch Co., 932 Powers Regulator Co., 930-931 Sarco Company, Inc., 952-953 Spence Engineering Co.. 933 Taylor Instrument Companies, 134 935 ^ Trane Company, The, 838-839 White-Rodgers Elec. Co., 937 Yarnall-Waring Co., 1012 VENTILATORS, Roof Airtherm Mfg. Co., 827 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 DeBothezat Division,. American Machine & Metals. Inc., 883 General Electric Company, 816- ttl 7 RQO_OQ*3 llg Electric Ventilating Co.. 884 Johns-Manville. 1040-1041 WATER COOLING TOWERS (See Cooling Towers, Water) WATER FEEDERS (Set Feeders Water) ' WATER HEATERS {See Heaters, Hot Water Service) WATER TREATMENT VALVES, Water Regulating B. F. Sturtevant Co,, 886 American Blower Corp., 802-803 ' Bell and Gossett Co., 941 Crane Company, 968-969 * Detroit Lubricator Co., 914-915 Fulton Sylphon Co., 918-919 General Refrigeration Corp., 870 Johnson Service Co., 922-923 Kieley & Mueller, Inc., 1009 Manning, Maxwell & Moore, Inc., 925 McDonnell & Miller, 960-961 Minneapotis-Honeywell Regulator Co., 926-927 Mueller Steam Specialty Co., 1010 Penn Electric Switch Co.. 932. Powers Regulator Co., 930-931 Spence Engineering Co., 933 York Ice Machinery Corp.,-811 VAPOR HEATING SYSTEMS {See Heating Systems, Vapor) VENTILATORS. Unit American Blower Corp., 802 American Coolair Corp., 878-879 Buffalo Forge Company, 881 Davies Air Filter Corp., 849 Hg Electric Ventilating Co.. 884 Herman Nelson Corp., 835 John J. Nesbitt, Inc., 836 Staynew Filter Corp., 852-853 B. F. Sturtevant Co.. 886 Trane Company, The, 838-839 L. J. Wing Mfg. Co., 890-891 Young Radiator Company, 841 / VENTILATORS. Window American Air Filter Co., 846-847 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 Cochrane Corp., 1005 . Oakite Products, Inc., 856 Vinco Company, Inc., 958-959 WEATHER INSTRUMENTS, Indicating and Recprding Bristol Company, The, 916 Julien P. Friez & Sons, Div. of Bendix Aviation Corp., 917 Johnson Service Co., 922-923 Leeds & Northrup Co., 924 Palmer Company, The, 929 Powers Regulator Co., 930-931 Taylor Instrument Companies, 934 935 WEATHERSTRIPS, Metal Chamberlin Metal Weather Strip Co.. 1018-1019 VENTILATORS. Attic {See also Fans, Electric, Propeller and Ex haust) American Blower Corp., 802-803 American Coolair Corp., 878-879 Autovent Fan & Blower Co., 877 Buffalo Forge Co., 881 Burnham Boiler Corp., 967 Buffalo Forge Company, 881 Coppus Engineering Corp., 848 Davies Air Filter Corp., 849 General Refrigeration Corp., 870 Ilg Electric Ventilating Co., 884 F. Jaden Manufacturing Co., 829 H. J. Somers, Inc., 854 Staynew Filter Corp., 852-853 B. F. Sturtevant Co., 886 "WELDINC FITTINGS {See Fit tings, Welding) WELDING ROD Carnegie-Illinois Steel Corp., 909 Wickwire Spencer Steel Co., 906 WHEELS. Blower Champion Blower & Forge Co., 882 American Blower Corp.. 802-803 Clarage Fan Co., 805 VIBRATION ABSORBERS {See Autovent Fan & Blower Co., 877 DeBothezat Division, American also Sound Deadening) Bayley Blower Company, 880 Machine & Metals, Inc., 883 Armstrong Cork Company, 1025 Buffalo Forge Company. 881 GarWood Industries, Inc., 818-819 Mundet Cork Company, 1044 General Electric Company, 816 Champion Blower & Forge Co., 882 Clarage Fan Company. 805 817, 892-893 Ilg Electric Ventilating Co., 884 Lau Blower Company, 885 WARM AIR FURNACES Furnaces, Warm A ir) {See Henry Furnacd & Foundry Co., 822 Lau Blower Co., 885 L. J. Mueller Furnace Co., 824-825 H. J. Somers, Inc., 854 B. F. Sturtevant Co., 886 WARM AIR HEATING SYS Torrington Mfg. Co., 887-889 TEMS {See Heating Systems, United States Air Conditioning ' Furnace) Niagara Blower Company, 806 B. F. Sturtevant Co., 886 Torrington Mfg. Co., 887-889 United States Air Conditioning Corp., 810 Corp., 810 Westinghouse Elec. & Mfg. Co., WATER COOLING {See also Cool 808-809, 855 ing Equipment, Water; Cooling WINDOWS, Supplementary , L. J. Wing Mfg. Co., 890-891 Towers) Sash . Aerofin Corporation, 862-864 Chamberlin Metal Weather Strip VENTILATORS, Floor and Wall Airtemp Div., Chrysler Corp., 812 Co.. 1018-1019 American Blower Corp., 802-803 813 Libby-Owens-Ford Glass Co., 1020 American Coolair Corp., 878-879 Baker Ice Machine Co., 866 1021 Please mention THE GUIDE 1940 when writing to Advertisers 1088 -v & by ; ' ' ---."I;: *> Roll of Membership American Society of heating and ventilating Engineers 1940 Contains Lists of Members Arranged Alphabetically and Geographically, also Lists of Officers and Committees, Past Officers and Local Chapter Officers Corrected to January 1, 1940 . \ Published at the Headquarters of the Society 51 Madison Avenue, New York, N. Y. . i i ENGINEERS OF HUMAN COMFORT THE Heating, Ventilating and Air Conditioning Engineer through his work and research brings to our homes, our offices and our factories, in both summer and winter, that climate best suited to our ' comfort and health. He is truly an Engineer of Human Comfort. . In September 1894, a little group of engineers, educators and manu facturers gathered in New York and agreed that the great art of heating and ventilating deserved and required recognition as an essential, dis tinctive and highly specialized division of modern engineering. These men realized the basic importance of heating and ventilating as the primary element in the well-being of civilized mankind, living and working mostly indoors. They foresaw the need for research and one of the first acts of the organized body was to establish a Committee on Standards. That the Charter Members had great faith in their enterprise is evident, although little did they dream that progress would be so rapid in their profession. During the intervening years since that little group of 75 pioneers unfurled the banner of The American Society of Heating and Venti lating Engineers--3,147 of the real leaders of thought and action in heating, ventilating, and air conditioning have gathered about that standard and carried it proudly before them far along the way of real accomplishment. They may be identified among engineering groups by the distinctive emblem which was adopted by the Charter Members. The first Annual Meeting was held in New York, N: Y., January 22-24, 1895, and the organization was incorporated under the laws of the State. The Society now has 3,147 members on its rolls, including engineers, educators, scientists, physicians, architects, contractors, and leaders of industry. There are four classes of active members, namely: Member, Associate, Junior and Student. The management of the Society is entrusted to 4 Officers and a Council of 13 members. Continuity of policy is insured by electing 4 men annually for a 3 year term and retaining the retiring president on the Council for 1 year. Research work is in charge of the Committee on Research , consisting of 15 members, 5 being elected annually for a period of 3 years. The three major activities of the Society are: Membership Service, Publication and Research, the record of its accomplishments being permanently recorded in the annual Transactions. . Headquarters of the Society are maintained in The New York Life Building, 51 Madison Avenue, New York, N. Y. Officers and Council American Society of Heating and Ventilating Engineers 51 Madison Ave., New York, N. Y. 1939-40 PresidentL_...................... First Vice-President.____ Second Vice-President__ Treasurer............... ........ Secretary......._......... ....... Technical Secretary......... .......J. F. McIntire .......F. E. Giesecke ......W. L. Fleisher --M. F. Blankin A. V. Hutchinson ...............John James Council One Year J. J. Aeberly M. C. Beman E. O. Eastwood E. Holt Gurney W. A. Russell J. F. McIntire, Chairman F. E. Giesecke, Vice-Chairman Two Years N. D. Adams A. P. Kratz J. H. Walker G. L. Wiggs . Three Years E. K. Campbell S. H. Downs A. J. Offner G. L. Tuve Committees of the Council Executive: F. E. Giesecke, Chairman; W. L. Fleisher, E. O. Eastwood. Finance: A. J. Offner, Chairman; E. O. Eastwood, J. H. Walker. Meetings: A. P. Kratz, Chairman; G. L. Tuve, G. L. Wiggs. Membership: E. K. Campbell, Chairman; N. D. Adams, W. A. Russell. Standards: S. H. Downs, Chairman; J. J. Aeberly, M. C. Beman. . Advisory Council E. Holt Gurney, Chairman; Homer Addams, R. P. Bolton, D. S. Boyden, W. H. Carrier, S. E. Dibble, W. H. Driscoll, H. P. Gant, John F. Hale, L. A. Harding, H. M. Hart, C. V. Haynes, E. Vernon Hill, John Howatt, W. T. Jones, D. D. Kimball, G. L. Larson, S. R. Lewis, Thornton Lewis, J. I. Lyle, F. B. Rowley, F. R. Still and A. C. Willard. . 1 Cooperating Committees . A.S.H.V.E. Representative on A.S.A. Sectional Committee on Standardization of a Scheme for Identification of Piping Systems (A-13): E. E. Ashley. A.S.HiV.E. Representative on NFPA Blower Systems Committee: N. A. Hollister.' 23 Special Committees Committee on Admission and Advancement: T. H. Urdahl, Chairman {one year); R. C. Bolsinger {two years), L. W. Moon {three years). Publication Committee: W. M. Sawdon, Chairman {one year); W. H. Severns {two years), P. Nichoils (three years). Guide Publication Committee: F. C. McIntosh, Chairman; P. D. Close, C. M. Humphreys, A. J. Offner, S. S. Sanford. ' Committee on Constitution and By-Laws: R. H. Carpenter, Chairman; J. F. S. Collins, Jr., W. T. Jones. A .S.H. V.E.--I.E.S. Committee on Lighting in Air Conditioning: H. M. Sharp, Chairman; E. E. Ashley, A. A. Brainerd, A. D. Cameron, F. H. Faust, W. F. Friend, W. E. Stark, and Walter Sturrock. Committee on Engineering in Its Relation to Public Health: J. J. Aeberly, Chairman; W. H. Carrier, Philip Drinker, E. V. Hill, John Howatt, A. C. Willard and B. M. Woods. Educational Publicity Committee: J. M. Frank, Chairman; W. H. Carrier, C. K. Foster, E. D. Harrington, H. M. Hart, L. C. Harvey, E. W. Lloyd, and J. O. Ross. Regional Meetings Committee: A. J. Offner, Chairman; J. J. Aeberly, and R. C. Bolsinger. A.S.H. V.E.--A.S.T.M. Committee on Thermal Conductivity: F. C. Houghten, Chairman; C. B. Bradley, H. C. Dickinson, R. H. Heilman, E. R. Queer, F. B. Rowley, T. S. Taylor, and G. B. Wilkes. F. Paul Anderson Award Committee: F. E. Giesecke, Chairman; E. O. Eastwood, W. T. Jones, A. P. Kratz, and S. R. Lewis. Comrnittee on Engineering Scholarships: N. D. Adams, Chairman; F. E. Giesecke, . G. L. Larson, F. B. Rowley, and B. M. Woods. . Committee on Code of Procedurefor Guidance of Committee on Admission and Advancement: W. T. Jones, Chairman; M. F. Blankin, F. C. McIntosh, and T. H. Urdahl. Committee to Study Method of Selecting Society Officers and Council Members: H. H. Erickson, Chairman; R. H. Carpenter, E. H. Gurney, W. T. Jones, J. F. Mclntire, and W. A. Russell. Speakers Bureau Committee: ,E. N. McDonnell, Chairman; John Howatt, W. G. Boales, and W. A. Russell. Chapter Atlanta Cincinnati Golden Gate Illinois Iowa-Nebraska Kansas City Manitoba Massachusetts Michigan Western Michigan Minnesota Montreal New York Western New York Northern Ohio Oklahoma Ontario Pacific Northwest Philadelphia Pittsburgh St. Louis . Southern California North Texas South Texas Washington, D. C. Wisconsin Nominating Committee Representative C. L. Templin H. E. Sproull G. M. Simonson , Tom Brown ` W. R. White ' . C..A. Flarsheim, William Worton .. . . James Holt ' F. J. Linsenmeyer W. W. Bradfield R. E. Backstrom L. H. Laffoley H. G. Meinke J. J. Landers C. A. McKeeman E. W. Gray H. R. Roth R. O. Wesley H. H. Erickson R. A. Miller , E. E. Carlson H. M. Hendrickson L. L. Landauer W. H. Badgett S. P. Eagleton C. H. Randolph 4 Alternate T. T. Tucker ------... W. H-. Junker G. J. Cummings M. W. Bishop T. R. Johnson N. W. Downs R. L. Kent D. S. Boyden W. C. Rans*ll L. G. Miller J. E. Swenson G. L. Ballantyne O. O. Oaks L. P. Saunders D. L. Taze A. A. Hoppe C. Tasker Lincoln Bouillon H. H. Mather F. C. McIntosh C. F. Boester S. H. Berringer C. R. (Gardner A. J. Rummel L. Ourusoff Ernest Szekely COMMITTEE ON RESEARCH^ W. L. Fleisher; Chairman ' ... ' J. H. Walker, Vice-Chairman F. C. Houghten, Director C.-E. A. Winslow, Technical Adviser A. C. Fieldner, Ex-Officio Member One Year H. E. Adams A. E. Stacey, Jr. G. L. Tuve J. H, Van Alsburg J. H. Walker Two Years M. K. Fahnestock W. L. Fleisher R. J. Tenkonohy T. H. Urdahl B. M. Woods Three Years R. E. Daly . W. A. Danielson H. J..-Rose C. TAsker . C.-E. A. Winslow A. E. Stacey, Jr. . Executive Committee . W. L. Fleisher, Chairman . T. H. Urdahl j. H. Van Alsburg ' J. H. Walker . L. T. Avery Finance Committee J. H. Walker, Chairman - E. Holt Gurney .. H. J. Rose . .. T. H. Urdahl " ' ' Technical Advisory Committees Relations.of Air Conditions to Human Health and Comfort--C.-E. A, Winslow*, General Chairman. . (a) Sensations of Comfort--LC. Tasker*, Chairman; C. R. Bellamy, Thomas Chester, . .Elliott Harrington, W. S. Kilpatrick, Dr. W. J. McConnell, A. B. Newton, ' B. F. Raber, L. C. Soule. . . (b) Physiological Reactions--C.-E. A. Winslow*, Chairman; Dr. T. Bedford, Dr. E. .. . . F. DtiBois, Dr. R. W. Keeton, Andre Missenard, Dr. R. R. Sayers, Dr. Charles Sheard, C. Tasker*. . .(e) Treatment of Disease--Dr. M. B. Ferderber, Chairman; Dr. C: J. Barone, . . , Dr; A. R. Behnke, Dr. B. Z. Cashman, W. L. Fleisher*, Dr. Ti L. Haziett, C. S. Leopold, Dr. C. D. Selby, Dr. A. W. Sherrill, Dr. H. F. Smith, Dr. C. S. . Stephenson, Dr. B. L. Vosburgh. . {d) Climate and Season--J. H. Walker*, Chairman; Dr: H. A. Abramson, O. W. Armspach, Ellsworth Huntington, Dr. C. A. Mills, Andre Missenard, T. H. Urdahl*. (e) Air Conditioning in Industry--A. E. Stacey, Jr.*, Chairman; Philip Drinker, Dr. Leonard Greenburg, H, P. Greenwald, A. M. Kinney, J. W. Kreuttner, L. L. Lewis, Dr. W. J. McConnell, Dr. C. P- McCord, P. A. McKittrick, Dr. R. R. Sayers, Dr. Charles Sheard, C. Tasker*, R. M. Watt, Jr. Air Pollution and Purification--C.-E. A. Winslow*, General Chairman. {a) Air Pollution--H. B. Meller, Chairman; F. A. Chambers, Philip Drinker, J. S: Owens; Sol Pincus, H. J. Rose*, R. J. Tenkonohy*, E. C- Webb, E. H. Whitlock, >-, . (b) Removal Atmospheric Impurities--Dr. Leonard Greenburg; Chairman; R. D. Bennett, R. S. Dill, Theodore Hatch, L. R. Koller, F. H. Munkelt, G. W. Penney, Dr. E. B. Phelps, F. B. Rowley, C. Tasker*, W. O. Vedder, Jack Waggoner, W. F. Wells, Dr. Rene Wiener. ' Radiation and Comfort---J.-C. Fitts,-Chairman; A. H. Barker, L. M. K. Boelter, R. E. Daly*, E. R. Gurney, L. N. Hunter, C. S. Leopold, A. P. Kratz, D. W. Nelson, G. W. Penney, W. R. Rhoton, C.-E. A. Winslow*. ... Instruments--D. W. Nelson, Chairman; F. R. Bichowsky, L. M. K. Boelter, R. S. Dill, M. K. Fahnestock*, A. P. Gagge, J. A. Goff, G. L. Tuve*, C. P. Yaglou. Weather Design Conditions--T. H. Urdahl*, Chairman; J. C. Albright, John Everetts, Jr., E. W. Goodwin,. J. B. Kincer, O. A. Kinzer, J. W. O'Neill, L. S. Durusoff, F. W. Reichelderfer. ; . ' Transportation Air Conditioning--A. E. Stacey, Jr.*, Chairman; W I. Cantley, T. R. Crowder, A. G. Dixon, C. C. Elmes, L. H. Laffoley, E. A. Russell, j. H. Van Als burg*, W. E. Zieber. Radiation with Gravity Air Circulation--M. K. Fahnestock*, Chairman; R. E. Daly*, ' A. G. Dixon, H. F. Hutzel, J. P. Magos, J. W. McElgin, J..F, Mclntire, T. A. Novotney, W. A: Rowe. . Heat Transfer of Finned-Tubes with Forced Air Circulation--G. L. Tuve*, Chairman; William Goodman;, W. E. Heibel, H. F. Hutzel, S. F. Nicoll, R. H: Norris, L. P. Saipiders, C. F. Wood. ' *Member of Committee on Research. 5 Cooling Load in Summer Air Conditioning--C. S. Leopold, Chairman; C. M. Ashley, John Everetts, Jr., F. H. Faust, M. G. Kershaw, A. E. Knapp, L. S. Morse, A. E. Stacey, Jr.*, R. M. Strikeleather, J. H. Walker*. , Solid Fuels--R. A. Sherman, Chairman; W. A. Danielson*, R. S. Dill, H. N. Eavenson, A. C. Fieldner, L. N. Hunter, A. J. Johnson, R. E. Kerr, H. K. Kugel, Percy Nicholls, . V. F. Parry, H. J. Rose*, D. M. Rugg, J. E. Schoen, L. E. Seeley, E. T. Selig, R. Templeton Smith, C. Tasker*. Summer Air Conditioning for Residences--M. K; Fahnestock*, Chairman; C. F. Boester, E. A. Brandt, John Everetts, Jr., Elliott Harrington, H. F. Hutzel, J. A. Kiesling, E. D. Milener, K. W. Miller, R. E. Robillard, F. G. Sedgwick, J. H. Walker*. . Air Distribution and Air Friction--J. H. Van Alsburg*, Chairman; S. H. Downs, M. K. Fahnestock*, R. D. Madison, Axel Marin, L. G. Miller, D. W. Nelson, C. H. Randolph, D. J. Stewart, Ernest Szekety, M. C. Stuart, R. J. Tenkonohy*, G. L. Tuve*. Heat Requirements of Buildings--P. D. Close, Chairman; W. H. Badgett, E. K. Campbell J. F. S. Collins, Jr., E. F. Dawson, W. H. Driscoll, H. M. Hart, H. H. Mather, F. B. Rowley, J. H. Walker*. .. Air Conditioning Requirements of Glass--M. L. Carr, Chairman; F. L. Bishop, W. A. Danielson*, H. C, Dickinson, J. E. Frazier, S. O. Hall, E. H. Hobbie, C. L. Kribs, Jr., R. A. Miller, F. W. Parkinson, Harold Perrine, W. C. Randall, L. T. Sherwood, . J. T. Staples, G. B. Watkins, F. C. Weinert. Insulation--R. T. Miller, Chairman; E. A. Allcut, R. E. Backstrom, Wharton Clay, R. E. Daly*, W. A. Danielson*, H. C. Dickinson, J. D. Edwards, W. V. Hukill, E. C. Lloyd, Paul McDermott, E. W. McMullen, W. T. Miller, E. R. Queer, T. S. Rogers, F. B. Rowley, W. S. Steele, J. H. Waggoner, G. B. Wilkes. Sound Control--J. S. Parkinson, Chairman; C. M. Ashley, A. M. Greene, Jr., A. E. Kimball, V. O. Knudsen, R. F. Norris, C. H. Randolph, J. P. Reis, W. P. Roop, A. E. Stacey, Jr.*, G. T. Stanton, F. R. Watson. Cooling Towers, Evaporative Condensers and Spray Ponds--B. M. .Woods*, Chairman; , J. C. Albright, S. C. Coey, E. H. Hyde, E. H. Kendall, S. R. Lewis, J. Lichtenstein, . J. F. Park, E. H. Taze. ... Psychrometry--F. R. Bichowsky, Chairman; D. B. Brooks, W. H. Carrier, H. C. Dickin son, A. W. Gauger, J. A. Goff, William Goodman, A. M. Greene, Jr., L. P. Harrison, F. G. Keyes, D. M. Little, D. W. Nelson, W. M. Sawdon, F. O. Urban. Corrosion--A. R. Mumford, Chairman; H. E. Adams*, J. F. Barkley, W. H. Driscoll, T. J. Finnegan,' W. Z. Friend, R. R. Seeber, F. N. Speller, A. E. Stacey, Jr.* Member of Committee on Research. Officers of Local Chapters, 1939-40 Atlanta ' Headquarters. Atlanta, Ga. Meets: First Tuesday in Month President, C. L. Templin, . 348 Peachtree St., N. E. Secretary, T. T. Tucker 260 Peachtree St., N. W. Cincinnati Headquarters, Cincinnati, O. Meets: Second Tuesday in Month President, H. E. SproIjll 1005 American Bldg. Secretary. W. H. Junker 6068 Dryden Ave. . Golden Gate Headquarters, San Francisco, Calif. Meets: First Tuesday in Month President, G; M. Simonson 74 New Montgomery St. Secretary, J. A. Hill 245 Market St. ' Illinois' Headquarters. Chicago, 111. Meets: Second Monday in Month President, Tom Brown .' 1805-27 N. Kostner Ave. Secretary, M. W. Bishop Iowa-Nebraska -Headquarters. Omaha, Nebr. Meets: Second Tuesday in Month President, T. R/ Johnson - .. . . Hubbell Bldg., Des Moines, la. Secretary, Perry La Rue " 629-3rd St., Des Moines, la.; . > Kansas City Headquarters, Kansas City. Mo. - . Meets: .Second Monday in Month . President, A. D. Marston ' ' 1330 Baltimore . Secretary, Henry Nottberg, Jr. 914 Campbell St. / v . ' . Manitoba > Headquarters, Winnipeg, Man. Meets: Third Thursday in Month President, G. C. Davis . 307 Power Bldg. . Secretary, Ivan McDonald 501 Ryan Bldg. Massachusetts Headquarters. Boston, Mass. Meets: Third Tuesday in Month President, H. C. Moore Massachusetts Institute of Technology. Cambridge, Mass., - Secretary, C. M. F. Peterson Massachusetts Institute of Technology, Cambridge. Mass. . 6 .5 Officers and List of Chapters, 1939-40--(Continued) Michigan Headquarters, Detroit, Mich. Meets: First Monday after the 10th ofthe Month President, W. C. Randall 2250 E. Grand Blvd. Secretary, W. H. Old 1761 Forest Ave., W. Oregon Headquarters, Portland, Ore. Meets: First Friday in Month President, J. D. Kroeker 926 Failing Bldg. Secretary, C. E. Heinkel 222L Northeast Breadway Western Michigan Headquarters, Grand Rapids, Mich. Meets: Second Monday in Month President, B. F. McLouth ' 135 E. Gunson St.. E. Lansing, Mich. Secretary, C. H. PeSterfield Michigan State College. E. Lansing. Mich. Pacific Northwest Headquarters, Seattle. Wash. Meets: Second Tuesday in Month President, R. O. Wesley 334 Boren Ave., N. . Secretary, H. T Griffith 324-1411 4th Ave. Bldg. - Minnesota Headquarters, Minneapolis. Minn. ~ Meets: Second Monday in Month President, F. C. Winterer 300 Broadway, St. Paul, Minn. Secretary,. H. M. Betts . 213 City Hall, Minneapolis, Minn. Montreal Headquarters. Montreal, Que. Meets: Third Monday in Month President, C. W. Johnson 630 Dorchester St., W. Secretary, F. G. Phipps 5431 Earnsciiffe Ave. . * ' Philadelphia . .Headquarters, Philadelphia, Pa. Meets: Second Thursday in Month . President, R. F. Hunger 220 South 16th St. Secretary, Edwin Elliot 560 North 16tb St. . . Pittsburgh Headquarters, Pittsburgh, Pa. . ' Meets: Second Monday in Month President, R. A. Miller 2200 Grant Bldg. Secretary, T. F. Rockwell' Carnegie Institute of Technology . New York ' Headquarters, New York, N. Y. - Meets: Third Monday in Month President, O. O. Oaks ` 119 Oakridge Ave., Summit, N. J. Secretory, T.'W. Reynolds 100 Pinecrest Dr., Hastings-on-Hudson, N. Y. St. Louis Headquarters, St. Louis, Mo. Meets: First Tuesday in Month President, R. J. Tenkonohy 3650 Shaw Blvd. Secretary, C. F. Boester 101 E. Essex, Kirkwood . . Western New York .Headquarters. Buffalo, N. Y. Meets: Second Monday in Month President, L. P. Saunders 507 Pine St., Lockport, N. Y. Secretary, H. C. Schafer 45 Church St-, Buffalo, N. Y. . Southern California . Headquarters, Los Angeles, Calif. . Meets: Second Tuesday in Month ; President, J. F. Park 1234 S. Grand Secretary, E. P; Wells 2730 E. Eleventh St. :. . North Carolina North Texas Headquarters, Durham, N. C.' Headquarters. Dallas, Tex. President, R. B. Rjce . ' . 1University of North Carolina, Raleigh, N. C. Secretary, T. C. Cooke `. 400 E. Peabody St., Durham, N. C. . Meets: Second Monday in Month President, C. L. Kribs, Jr. 4209 Shenandoah Ave. Secretary, L. S. Gilbert 1314 Liberty. Bank Bldg. . - . Northern Ohio.' Headquarters, Cleveland. O. South Texas Meets: Second Monday in Month Headquarters, Houston, Texas President, H. E. Wbtzell " 6107 .Carnegie Ave. Secretary, C. M. H. Kaercher 3030 Euclid Ave- ' ;. Oklahoma Headquarters, Oklahoma City, Okla. Meets: Second Monday in Month President, A. A. Hoppe 213 W. First St. Secretary, S. L. Rolland 321 N. Harvey Ave. . Meets: Third Friday in Month President, C. A. McKinney 1018 Rusk Bldg. Secretary, D, S. Cooper ' . 2615 Fannin St. . . . : ' . . ' ' Washington; D. C.-; . Headquarters, Washington, D. C. Meets: Second Wednesday in Month President, T. H. Urdahl 726 Jackson Place, N. W. Secretary, P. H. Loughran, Jr. 45l3-49th St. , - Ontario Headquarters, Toronto, Ont. Meets: First Monday in Month President, H. D. Henion 1623 Davenport Rd. Secretary, H. R. Roth 57 Bloor St., W. , Wisconsin . * Headquarters, Milwaukee, Wis. Meets: Third Monday in Month - ` President. H. C. Frentzel . .. 4363 N. Wildwood Ave. . Secretary, W. A. Ouwenebl ' 801 Marshall Ave., South Milwaukee, Wis. 7 HOW TO APPLY FOR MEMBERSHIP The real accomplishments of life are ' usually measured by the service one has rendered to his fellows and. the true cul tural refinement of mind, the finest sense of personal and professional ethics, factors transcending all material elements in what man calls "success," are developed through association with those of . high, ideals and cherished ambitions in the same field of activity. The American Society of Heating and Ventilating. Engineers offers to him whose work is definitely within its province-ran opportunity for such association and' an opportunity for real service to his profession. Every man in the heating, ventilating and air conditioning profession needs the Society-- * 1--Because of the contacts that it brings through national and local meetings. 2---Because of the information supplied by Society Publications. 3--Because of .the., opportunities that re search reveals-in new applications for engineering services and equipment. 4---Because of the satisfaction to be de rived in contributing to human comfort and well being. A Candidate must make, application on the printed form "Membership Appli cation" which is available at the head quarters office or from Chapter Officers and members. A statement of qualifi cations and engineering experience is required and four members must act as sponsors except under certain conditions noted in Article -111 of the By-Laws. Initiation Fees for 1940 are: Members and Associate Members $10.00; Junior Members $5.00. The Initiation Fee must accompany application. For 1940 the annual dues of the Society are: Members and Associate .^4embers $18.00; Junior Members $10.00; and Student Membership $3.00. Dues of new members are pro-rated on a quarterly basis; , C-ll--Article Membership Section 1. Persons connected with the arts and sciences related .to heating, venti lating or air conditioning are eligible for admission into the Society.. Section 4- A Member shall be thirty (30) years of age or over and shall;be a person of experience in the science of heat transfer in its application to the art of heating, ventilating or air conditioning, and shall have been in active practice of his profession and in responsible charge of important work for five (5) years and shall be qualified to design as.well as to direct such engineering work. ... Section 5. A Junior Member shall be a person over twenty (20) years and under thirty (30) years, of age, who has been actively engaged in the work of heating, ventilating or air Conditioning for. three (3) years, or is a graduate of a school of engi neering of recognized standing; Section 6. An Associate Member shall be twenty-five (25)' years of age or over. He need not be an engineer, but must have been so connected with some branch of engineering or the art of heating, venti lating, air conditioning or the industries relating thereto, that he may be considered as qualified to cooperate with heating and ventilating engineers in the advancement of professional knowledge. . y Section 7. A Student Member shah be a person between the ages of 18 and 25 years, who is regularly attending courses in an engineering college or technical school at the time of applying for member ship. 8 Roll of Membership American Society of Heating and Ventilating Engineers 1940 - - (Corrected to January 1, 1940) HONORARY MEMBERS BALDWIN, WM. J. (1915), New York, N. Y. (Deceased Mav 7 1924 ) (^96), New. York, N. Y. (Deceased March 10 1913 ) > ^I9^?GINALD PELHAM (1897), New York. N. Y (1920), North Ferrisburg, Vt. ' Pa- (Deceased January 31, 1929.) f935C)harter Menlber)' <Presidential Philadelphia, Pa. LIST OF MEMBERS Arranged Alphabetically ...'. (Asterisk Indicate, authorshipof papers) . A. ' ABBOTT, Thomas J. (M 1938) Vice-Pres, (for mail)-Geo. C. Abbott. Ltd., 119 Harbord St., and 42.Ardmore Rd., Toronto, Ont., Canada. ABRAMS, Abraham (M 1927: J 1924) Pres.. Abbey Heating Co., Inc., 81 Centre Ave.. and . (for mail) 100 Clove Rd., New Rochelle. N. Y. ABRAMSON, Ralph J. (A 1938) Estimating & Design Engr., Hipskind Heating & Plumbing Co.. 1725 Winter St., and (for mail) Rte. No. I Fort Wayne. Ind. ' .. ACHESON, Albert R. (M1919) Consulting Engr.. 501! Eckel' Theatre Bldg., and (for mail) 852- Ostrjom;Ave.;Syracuse, N. Yj - .... ADAM, Rar W. (A . 1938) Owner. William A Adam Co. (for mail) 8810 Grinnell Ave., and 5911 Courville AVe.. Detroit, Mich. .. ADAMS, Bruce P. (A.1936) Gen. Mgr. (for mail) McDonnell & Miller, 400 N.! Michigan Ave.-. and I432:Rascher Ave., Chicago, III. ADAMS, Chest** Z. (if 1939) Br. Mgr. (fbrmail) Ug-Electric Ventilating Co., Boat 1356, and A6. Dolly Madison Apts., Greensboro, N.' C. . ADAMS, Eugene E. (A 1938) Sales Engi. (for 'I;.IU,.) Garden City Fan Co., Room 1508A', 65 W 42nd St;, New York, and 3M6 79th St., Jackson Heights. L. I., N. Y. . .jscsson ADAMS. .Frank L; (if 1939) Htg. & Air Cond. li.h-ngr., FttbUc Sedce Co. of Colorado, and (for . mail).1331 14th Ave., Denver, Colo. . ADAMS, Harold Ei (if 1930) .Chief. Engr. (for mail),Nash EngineenngCo., Wilson Rd..,S6uth Norwalk and Merrill Heights.' Norwalk, Conn ADAMS; NelID;:(if, 1929;. A 1925; J 1922) (Council, 1938, 1939) Supt. (for, mail) Franklin . Heating Station, ;220-2nd Aye., S.W., and-8368th Ave., S.W.. Rochester, Minn. * ADDAMS, Homer (Charter Member* Life'Member's (Presidential Member) (Pres.. 1924; 1st Vice- Pres.,"1923; Treas.; 1915-1922; Council. 1915. .1925). Pres. Kewanee Boiler-Go., Iric.. and Fitzgibbons, Bailer -Co., Inc., .101 Park Aye New .York, N.-Y. k. ...: . . .. '' ADDINGTON. Herbert B. (if 1938) Consulting Engr. (for mail) 13 E. 37th St., New York, and 25 Lafayette Ave.. Brooklyn. N. Y. ADDINGTON, H. M. (if 1939) Mech. Engr., War Dept- Furniture Warehouse. Ft. Myer, Va.. and (formail) 2120 "G" St.. N.W.. Washington, b. C. ADEMA, George E. (if 1939) Pres.. N. M sAd5?f ?9 w- Balcom St., Buffalo. N. Y. ADLAM. T. Napier (if ig32) Vice-Pres. and Gin. Sarco Mfg. Co.. 183 Madison Ave.. New N. Y.. and (for mail) 64 Wellington Ave.. West Orange, N. J. ADLER, Herman (J 1940; S 1938) Purchasing ,Artno Cooling Ventilating Co.,-,30 West l?th f,1" 5"?- (f?r "Ml) 485 Central-ParfWest, New York, N. Y. 1928)..(C0Uncil. 1937 1939) -ChieLof Div. of Htg.. Vtg. and IiftL.Sani- tation, Chicago Board of Health, 707 CUV.vHall. ((r mail) 6225 N. -Newcastle Ave^ Norwood r*ark P. O., Chicago,. Ill - - - - AHEARN. William Ji. (Jf..l929rHtilrand Vtg ' * JPStf 21 Rd- Cochituat'e, Mass. - V AHLFF, Albert A. (Af.. 1923;' A. 1918) -Tuttle & Bailey, Inc., New Britain, and (for mail) 310 a T^fminton Ave., Hartford, Conn. - . Joseph M.' (Af- T936) -CorisulUng. Air atB.-.Cujder Ave.-. Chicago,'til. ^SWORTH, SamuelfE '(A 1939V Sales Entf., Ro^c. HewJ9n. % Co., 1316 Texas Ave., and (for mail) 1524 25th St.; Lubbock, Tex. . . AKERMAN, Joseph Reid iJ,1937), Htgl: add Air Cond. Engr. (for mail). Phoeiux OiJ .Go,. 700 . J^gRs SL, and 831-I6th SL,vAugusU, Gal- AKERS, George .W. ;;(M T929). Secy.-Treas., George W. Akers Co.;j16525 Woodward Ave., Petroit. and (for mail):,R..Fs. D. No. 3. Birining- WSi^-^K-'Cnhlraitor . (ior maU) Alben Equipment Co.* 114 E. lOth St and. Rte. N6. 4,-Box 282;. 22: Brookaide. vYancouve'r. Wash: " * . L`: . ALBRIGHT, C. Barton .1938) Consulting.Air Cond. Engr. (fot..mail) -57 Washington St., Newark, and 26 Elitabeth St., Caldwell. N. j! a w HEATING VENTILATING AIR CONDITIONING' GUIDE 1940 ALEXANDER. Samuel W. (Af 1935) Pres.. S. W. ANDRESEN, Garwood C. (7 1938; S 1936) Office Alexander Co.. Ltd., 2494 Danforth Ave., and Mgr., York Ice Machinery Corp., 1128 Broad St.. (for mail) 124 Kingsraount Park Rd., Toronto. Hartford, and (for mail) Main St., Farmington, Ont., Canada. ALFAGEME, BrauUo (Af 1935) Engr; & Mgr.. B. . Conn. ANDREWS, George H. (A 1934) Partner and Atfageme. Almagro 1, Madrid. Spain. . . Supt., Frank P. Andrews & Son. 354 Neshanock ALFERY, Henry F. (Af 1938) Chief Engr. (for Ave., and (for mail) 213 Meyer Ave., New Castle. mail) Milwaukee Gas Specialty Co... 2025-W. Pa. Clybourn St., and 1819-W. Center St., Milwan- ' ANGERMEYER, Albert H. (A 1936) Owner (for kee, Wis. ' : mail) 119 N. Commercial St., and 705 E. Forest ALFSEN, Nikolai (Af 1933) Engr., Alfsen & Ave., Neenah, Wis. Gunderson. Prinsensgate 2b, Oslo, and (for mail) Utsiktsveien 22. Stabekk, Norway. ALGREN, Axel B.* (Af 1930) Asst. Prof. Mech. Engrg., Exp. Engrg. Lab., University of Minne sota, and (for mail) 5109-17th Ave.,.S., Minne ANGUS, Frank M. (Af 1937) Dist. Sales Mgr., General Refrigeration Corp., Beloit, Wis., and (for mail) 4936 Booth Ave.. Kansas City, Kan. ANGUS, Harry H.* (Af 1918) (Council, 1927-1929) . Consulting Engr., 1221 Bay St., and (for mail) f. apolis, Minn. ALLAIRE, Lucien (A 1939; 7 1937) Resident Engr., Dept, of Highways of the Province of 34 Farnham Ave., Toronto, Ont., Canada! ' ANNAS, Henry C- (A 1937) (for mail) Annas- Brady Co., 413 Murphy Bldg..and 361 Covington Quebec, Quebec City, and (for mail) 2182 Sherbrooke St., East Montreal, P. Q., Canada. ALLAN, William (A 1937) Pres. 8c Treas. (for mail) Allan Engineering Co.. 724 E. Mason St., and 2735 N. Farwell Ave., Milwaukee, Wis. ALLCUT, Edgar A.* (Af 1937) Prof, of Mech. Drive, Apt. 306, Detroit, Mich. ANSPACHER, Thomas H. (Af 1939; 7 1936) Dist. ; Mgr. (for mail) Buffalo Forge Co., 702 Tower Petroleum Bldg., and 4512 Arcady. Dallas. Tex. ANTHES, Lawrence L. (A 1935) Pres, (for mail) Imperial Iron Corp.. Ltd., 30 Jefferson Ave., and Engrg.. (for mail) University of- Toronto, and 48 Foxbar Rd., Toronto, Ont-. Canada. - 117 Dowling Ave., Toronto, Ont., Canada. . APT, Sanford R. (Af 1935) Engrg. Asst. Borough ALLEN, A. Walter (Af 1936) Sales Engr., Pease - ' Pres., Manhattan, Rm. 2142, Municipal Bldg., Foundry Co.; Ltd. (for mail) 151 Glen Ave.,; .. : New York, and .(for mail) 36-20 168th St.. Ottawa. Ont., Canada. ALLEN, DeWitf M. (Af 1936; 7 1922) Dist. Mgr. llg Electric Ventilating Co.. 310 Board of Trade Flushing. L. I., N. Y. ARCHAMBAULT, Joseph A. (A 1939) Mgr. (for mail) C. A. Dunham Co., Ltd., 22 Wellington St.. Bldg., Kansas City, Mo., and (for mail) 3924 N., and 55A Council St., Sherbrooke, P. Q., Cambridge..Kansas City,. Kan. - ALLEN, William A. (A 1938) Sales Engr., Electric Products Corp., 5624 Penn Ave., Pittsburgh, and Canada. ARCHER, David M. (Af 1934) Sales Repr. (for mail) Sarco Co., Inc., 143 Federal St., Boston, (for maii) 106 N. Fremont, Bellevue. Pa. ALLEN. William W. (A 1936) Pres, (for mail) American Coolair Corp., Box-2300, Jacksonville, . and Venetia, Fla. ALLENSWORTH, James E. (5 1939) Student (for mail) Box 290, Carnegie Institute of Tech nology; Pittsburgh. Pa., and Amsterdam, O. ALLONIER, Howard R. (A 1936) Dist. Sates Mgr. (for mail) J. J- Nesbitt Co., 425 W. Town .St., Columbus, and Rte. No. 1,-Powell, O. ' . and 87 Cabot Ave.. Braintree, Mass. ARDEN, Irwin L. (7 1937) Engr., Lutz Engineer- log Co.,' 1611 Westminster St., and (for mail) 87 Modena Ave., Providence, R. I. ARENBERG, Milton K. (A 1920) Pres, (for mail) . Robert Barclay, Inc., 122 N. Peoria St., Chicago, and Wildwood Lane, Highland Park, III. ARGUE, Edgar J. (A 1935) Sales Engr.. Anthes ' Foundry, Ltd., Saskatchewan Ave.; and (for mail) Ste. 11, Estelle Apts., Winnipeg, Man., ALLSOP, Rowland P. (A 1940; 7 1934) Engr. (for mail) Mathers 8c Haldenby, 96 Bloor St., West,and 89 Neville Park, Toronto, Ont., Canada. Canada. ' ARKLEY, Lome M. (Af, 1922) Head, Dept, of Engrg., Queen's University, Kingston, Ont., ALT, Harold L.* (Af 1913) Mech. Engr., Voorhees, Walker, Foley 8c Smith, 101 Park Ave., New ' York, and (for mail) 115-27 2515th St., St. Albans, L. I,, N. Y. AMES, Charles S. (7 1937) Jr. Mech. Engr.; State of California, Division of Highways, 1S05-34th St., and (for mail) 1127-39th St., Sacramento, Calif. AMMERMAN, Andrew S.. Jr. (7 1937) Engr., (for mail) Aerofin Corp., Room 704, 111 W. Washington St., and 4332 N. Hermitage Ave., Canada. - ARMBRUSTER, Frank T. W. (Af 1936) Pro fessional Engr., The Portsmouth Supply Co.. 1532-1534 Gallia Ave., Portsmouth, and (for mail) 105 First Ave-.Waverly, O. ARMISTEAD, William C. (Af 1937) Sales Engr. (for mail) William C. Armistead, 205 Church St., and Murfreesboro Rd., Nashville, Tenn. ARMOUR, Edson G. (S 1939) Student. Carnegie Inst, of Technology (for mail) 5010 Morewood PI., Pittsburgh, Pa., and 55-A Sheridan St.,. a Chicago. 111. AMMERMAN, Charles R. (Af 1916) Consulting ` Engr. (for mail) 772 Century Bldg., and 3908 Guilford Ave., Indianapolis. Ind. ANDEREGG. R. H. (Af 1920) Vice-Pres.. The Trane Co., and (for mail) '420 N. Losey Blvd., LaCrosse, Wis. \ ! ANDERSON,.Carroll S. (Af 1920) Mgr. (for mail) American Blower Corp., 1105 Architects Bldg.,. Brantford, Ont., Canada. ARMSPACH, Otto W.* (Af 1919) Vice-Pres. and Chief Engr., Kroeschell Engineering Co.. 215 W. Ontario St., Chicago, and (for mail) 205 S. Summit Ave., Villa Park. III. ARMSTRONG, Charles E. (Af 1939) Chief Engr., Armstrong Heat Control Go., 1626 N. E. Union Ave., and (for mail) 1307 N. E. 11th. Ave.. 816 W. Fifth St., Lee Angeles, and 4267 Holly Knoll Drive, Hollywood, Calif. ANDERSON. David B. (A 1939; 7 1936; 5 1933) Mgr., Sales Engrg. Dept., Wood Conversion Co., 1981-ist National Bank Bldg., and (for mail) 1999 Pinehurst Ave.. St. Paul, Minn, ANDERSON. Edwin J. (A 1939) Mfrs. Agent (for Portland. Ore. `' ARMSTRONG, Edward T. (S 1939) Instructor (for mail) Clarkson College of Technology, Potsdam, and 7901 Tenth Ave., Brooklyn, N. Y. ARMSTRONG, Walter J. (Af 1938) Consulting Engr. (for mail) 1010 St, Catherine St., West, Montreal, and 15 Willow Ave., Westmount, P. Q.. mail) 14 Smith St., and 274 Lenox, Detroit, Mich. ANDERSON. George A. M. (A 1939; 7 1936) Secy, (for mail) King Ventilating Co., and 717 S. Cedar, Owatonna. Minn. . . : Canada. ARNDT. Heinrich W. (A 1935) Mgr.. Plbg. and Htg. Dept., Sears Roebuck & Co., 732 Broad St., and (for mail) 1816 Wrightsboro Rd., Augusta. ANDERSON, John W. (7 1937) Engrg. Dept., The Conditioning Co., 368 Broad St., Newark, and (for mail) 548 Westminster Ave.. Elizabeth, N. J. . ANDERSON. P. Russell (7 1938) Radio Electric Inc., Chester, Pa., and (for mail) 17 East 25th St., Wilmington, Del. Ga. ARNOLD, Robert S, (A 1926; 7 1922) Proprietor. RobL Arnold Sales & Eng. Co., Otis Bldg., and (for mail) 6391 Sherwood Rd., Philadelphia. Pa- ARONSON, Henry H. (A 1939; 7 1929) Field Engr., Premier Furnace Co., Dowagiac, Mich., and (for mail) 6145 Winthrop Ave.'. Chicago,''111. f / 10 ROLL OF MEMBERSHIP ARROWSMITH, John O. (Af 1934) Plant Engr. (for mail) Canadian Kodak Co., Ltd., and 9 Humberview Rd., Toronto, 9, Ont., Canada. ARTHUR, John M., Jr. (M 1923) Commercial Sales Mgr. (for mail) Kansas City Power & Light Co., 1330 Baltimore Ave., Kansas City, Mo., and 3311 State Ave., Kansas City, Kan. ASHLEY, Carlyle M.* (Af 1931) Dir. of Develop ment (for mail) Carrier Corp., and 207 Brattle Rd., Syracuse, N. Y. ASHLEY, Edward E. (Af 1912) Consulting Engr. (foT mail) 10 East 40th St., New York, N. Y., and Middlesex Rd., Noroton Heights, Conn. ATHERTON, Alfred E. (A 1937) Dir. (for mail) A. E. Atherton & Sons Pty., Ltd., 383 Latrobe St., Melbourne, C. 1, and 39 Ormond Esplanade, Elwood, S. 3, Melbourne, Australia. ATHERTON, George R. (Af 1930) Mgr., Vento Dept., American Radiator & Standard Sanitary Corp., 820 S. Michigan Ave.. Chicago, and (for mail) 327 Franklin St., Geneva, 111. ATKINS, Thomas J. (Af 1931) Consulting Engr.. 68 Cathedral Ave., Nutley, N. J. AUCHMOODY, Frank W. (A 1938) Chief Engr. (for mail) E. R. Squibb Institute for Medical Research, Georges Rd., New Brunswick, and 323 S. 2nd Ave., Highland Park, N. J. AUER, George G. (A 1939) Pres, (for mail) Auer Register Co., 3608 Payne Ave., Cleveland, and 14015 Lake Ave., Lakewood, O. . AUGHENBAUGH, Harry E. (Af 1935) York Ice Machinery Corp., and (for mail) 481 Madison Ave., York. Pa. AUSTIN, William H. (7 1940; 5 1937) Sales Engr., York Ice Machinery Corp., 200 Causeway St., Boston, and (for mail) 630 Adams St., Milton, Mass. AVERY, Ledyard (A 1939) Engr., Carrier Corp.. and (for mail) 594 Roberta Ave., Syracuse, N. Y. AVERY, Lester T. (Af 1934) Pres, (for mail) Avery Engineering Co., 2341 Carnegie Ave., COl.eveland, and 21149 Colby Rd., Shaker Heights. AXEMAN, James E. (Af 1932; A 1931; 7 1925) Gen. Sales Mgr. (for mail) Spencer Heater Div. of Lycoming Mfg. Co.. Box 660, and N. Campbell St., Williamsport, Pa. B BACHMAN, Fred (Af 1936) Contractor (for mail) 3004 North 21st st., Philadelphia, and 906 Bell Ave., Yeadon, Pa. BACHMANN, Arthur J. (7 1940; 5 1939) Sales Repr., Alfred L. Hart. Jnc., 164-07 Hillside Ave., and (for mail) 139-15-86th Rd., Jamaica, L. I., N. V. BACHOFER, Henry A., Jr. (7 1938) Mgr., Htg. and Air Cond. Dept., Mid-West Plumbing Co., Ill South 5th St., and (for mail) 534 South 8th St., Salina, Kan. ' BACKSTROM, Russell E.* (A 1931; 7 1928) Mgr., Ind. Sales Dept, (for mail) Wood Con--' version Co., First National Bank Bldg., and 1655 Hillcrest, St. Paul, Minn. BACKUS, Theodore H. L. (Af 1916) (for mail) Schumacher & Backus, 200-208 Hill St., and 1018 Vaughn St., Ann Arbor, Mich. . BADARACCO, John A. (A 1937) Owner (for mail) Badaracco Appliance Co., 115 W. Monroe St., and 2 Southmor, Mexico, Mo. BADGETT, W. Howard* (Af 1937; 7 1932) Research Assoc, (for mail) Texas Engrg. Experi ment Station, A. & M. College of Texas, P. O. Box 213 Faculty Exchange, and 204 Pershing Ave.. College Station, Tex. BAENDER, Frederick G. (Af 1937) Consulting Engr., Drexel, Mo. . BAGGALEY, Walter (Af 1938) Asst. Chief Mech. Engr. (for mail) The Austin Co., 16112 Euclid Ave., Cleveland, and 3390 Glencaim Rd., Shaker Heights, O- BAHNSON, Frederic F.* (Af 1917) Vice-Pres. Secy, (for mail) The Bahnson Co., 1001 S. Marshall St., Pres., Southern Steel Stampings, Inc., and 28 Cascade Ave., Winston-Salem, N. C. BAILEY, Albert E,, Jr. (A 1938) Sales Engr.. Frigidaire Div., General Motors Sales Corp., 29 Franklin Rd., and (for mail) 1624 Patterson Ave.,* S. W.. Roanoke, Va. BAILEY, Charles F. (7 1939) Asst. Prof. Mech. Engrg. (for mail) Mississippi State College, Box 425, State College, Miss. BAILEY, Edward P. (Af 1925) Sales Engr., Detroit Stoker Co., 5-125 General Motors Bldg., Detroit, and (for mail) 151 Crocker Blvd., Mt. Clemens, Mich. BAILEY, F. A., Jr. (A 1939) Owner, Bailey's Refrigerating Sales & Service, 130 King St., Charleston, S. C. BAILEY, W. Mumford (Af 1930) Managing Dir., Mumford Bailey & Preston, Ltd., and Joint Managing Dir., British Trane Co., Ltd. (for mail) "Newcastle House" Clerkenwel) Close. London, E. C. 1, and "Oldbury Court", Dainesway, Thorpe Bay, Essex, England. BAIRD, S. Alan (Af 1935) Consulting Engr. (for mail) 609 Commercial National Bank Bldg., and 411 W, Melbourne Ave., Peoria. III. BAKER, C. T.* (Af 1935) Consulting Engr. (for mail) 713 Glenn St., S. W., and 31 The Prado, Atlanta, Ga. . BAKER, George R. (Af 1936) Pres, (for mail) G. R. Baker Co., Ltd., 224 Adelaide St., W., and 37 Lappin Ave., Toronto, Ont., Canada. BAKER, Harold S. (A 1937) Sales Engr., Re frigeration, 2015 Chester Ave., and (for mail) 241 Jefferson St., Bakersfield, Calif. BAKER, Harry L., Jr. (7 1935) Sales Engr. (for mail) American Blower Corp., 50 West 40th St., New York, and 146-V. Van Tassel Apts., N. Tarrytown, N. Y. ' BAKER, Howard C. (Af 1921) Pres, (for mail) The Howard Baker Co.. 128 S. St. Clair St., and 4604 Manorwood Rd., Toledo, O. BAKER, Irving C. (Af 1921) Vice-Pre9. in Charge of Sales (for mail) Crysler Corp., Airtemp Div., 1119 I-eo St., and Mad River Rd., Dayton, O. BAKER, Lome P. (7 1937) Air Cond. Engr. (for mail) Canadian General Electric Co., Ltd., Royce Ave. Works, 830 Lansdowne Ave., and 2553 Bloor St., W., Toronto, Ont., Canada. BAKER, Roland H. (Af 1928; A 1924) Pres., R. H. Baker Co., Elkins, N. H. BAKER, Thomas (Af 1938) Engr., Suburban Air Conditioning Corp., 7 Depot Plaza, White Plains. N. Y. ' BAKER. William C. (Af 1938) Pres., and Treas. (for mail) Electric Appliances, Inc., 155-7th Ave., N., and Westover Drive, Nashville. Tenn. ' BAKER, William H., Jr. (A 1935) Gen. Mgr. (for mail) Standard Air Conditioning Corp., 40 West 40th St., and 307 E. 44th St., New York, N. Y. BALDI, G. (A 1936) Engr. (for mail) Compagnia Italiana Westinghouse, Via Pier Carlo Boggio 20, Torino. Italy. BALDWIN, Karl F., Jr. (7 1938) Engr., McCrea Equipment Co., 516-2nd St., N.'W., Washington, D. C., and (for mail) 4810 Cedar St., Hyattsville, Md. ' BALDWIN, WUUam H. (Af 1921) Sales Engr. (for mail) C. A. Dunham Co., 5757 Cass Ave., and 2432 Atkinson Ave., Detroit, Mich. BALL, William (A 1936) Pres, (for mail) Inter State Heating & Plumbing Co.. 521 Southwest Blvd., Kansas City, Mo., and 1026 Shawnee Rd:, Kansas City, Kan.- ' BALLANTYNE, George L. (A 1936) Mgr., Htg. Sales Dept, (for mail) Crane.-Ltd., P. O. Box 840, and 141 Bedbrook Ave., Montreal, West, P. Q-, Canada. BALLMAN, William H. (Af 1937) Chief Engr., Air Cond. Div. (for mail) Nash-Kelvinator Corp., Long Island City, N. Y. - BALSAM, Charles P. (Af 1932) Owner, National Home Equipment Co., 11 West 42nd St., New York, and (for mail) 324 Fourth St., Brooklyn, - N. Y. . BAMOND, Manuel J. (Af 1936) Sales Engr. (for mail) Barber-Colman Co., 221 N. LaSalle St., and 4715 Magnolia Ave., Chicago, 111.' 11 HEAT1NC VENTILATING AIR CONDITIONING GUIDE 1940 BANACH, C. J. (J 1939) Chief Draftsman. John . son Fan:& Blower Corp.,-1319 W. Lake St., and (for mail) 1427 N. Leavitt SL, Chicago, 111. BANKS. John B. (A 1937) Branch Mgr. (for mail) Minneapolis-Honeywell Regulator Co., 2405 N. Maryland Ave.. and 292S N. Maryland Ave., Milwaukee, Wis. BANNER, Francis L. D. (M 1937) Branch Mgr. ' (for mail) Minneapolis-Honeywell Regulator Co., 378 Saunders-Kennedy Bldg., and 5523 Corby St., Omaha, Nebr. BANNON, Lucas E. (A 1935) Archt., 16 Church St.. Paterson, N. J. ' BANOWSKY. Aubra B. (M 1938) Commercial Sales Mgr.. United Gas Corp.. United Gas Bldg.. and (for mail) 3735-Ingold, Houston, Tex. BANTA, Guy L. (A' 1939) Branch Mgr. (for mail) The Trane Co.. 310 Postal Bldg., and Royal Manor Apts., 3rd 8c Mill SL, Portland. Ore. BARBIERI, Patrick J. (J 1936; S 1933) Engr., Arrao Cooling & Ventilating Co., 30 West 15 St., and (for mail) 1233 White Plains Rd., New York, N. Y. '' . BARNARD, M. Everett (A 1931; J 1929) Sales Engr. (for mail) Carrier Corp** 12 S. 12tb St., and 380 Vernon Rd., Philadelphia, Pa. BARNES, Arthur F. (M 1920) Owner (for mail) Texas Engineering Co., 726 Electric Bldg., and 3015 Jarrard St.. Houston, Tex. . . BARNES, Arthur R. (M 1924) Chief: Engr. (for mail) U. S. Supply Co.. 1315 West 12th St., and 326 East 70th Terrace. Kansas City,- Mo. BARNES, Herbert (M 1936) Mgr. (for mail) Herbert Barnes Plumbing 8c Heating. Delta Block, and 114 Grosvenor Ave., S., Hamilton, Ont.. Canada. ' ......................, . BARNES, Lewis L. (J 1937) Air Cond. 8c Refng. Engr., Carrier Atlanta Corp., 348 Peachtree St,, and (for mail) 3995 N. Stratford Rd., Atlanta, Ga. ,, BARNES. R. W. (M 1939) Htg. 8c Vtg. Contractor (for mail) 1208 Main Ave., San Antonio. Tex. BARNES, Walter E. (M 1933) Pres., Barnes 8c Jones, Inc., 128 Brookside Ave.. Jamaica Plain. Boston and (for mail) 7 Woodlawn Ave., Wellesley Hilts, Mass. BARNEY, William E. (M 1936) Mgr. (for mall) Hydraulic-Press Brick Co., South Park, and 4929 E. 108th St,, Cleveland. O. . BARNSLEY, Frank Richard (A 1936) Mgr.. Air Cond. Div. (for mail) Canadian General Electric Co.. Ltd;, 1000 Beaver Hall Hill, and 5245 Byron Avei,' Montreal P. Q ; Canada. 'BARNUM, Marvin C. (M 1930; A 1928) Eastern Repr. (for mail) Waterman-Waterbury Co., P. O. Box 284, Suflem, and'Cherry Lane, Tallman, N. Y. ' ' " - BARNUM, Willis E,, Jr. (M 1933; J 1930) Mgr., Air Cond. Div., York' Ice Machinery Corp., Roosevelt Ave., and (for mail) 35 N. Rockburn BARrTGeonle W. (Life Member-, M 1905) (Board -of Governors. 1910) Dist.' Mgr.. Aerofin Corp., 2030 Land Title Bldg., Philadelphia, and (for -mail) Woods End, Villa' Nova. Pal BARRY, James G., :Jr. (M 1933) Vice-Pres. (for mail) Elliott 8c Barry'fingineering Co.. 4060 W. Pine Blvd., and 5051 Queens Ave., St. Louis, BARRY; Patrick I. (M 1920) (Peace Commis sioner) M.I.H.V.E. Managing Director (for mail) M. Barry. Ltd., 4 Marlboro St., and 8 Sidney Park. Cork. Ireland..................... BARTELS. Everett M. (7 1939) Supvr. of Mech. Equip, (for mail) Independent School DisL, 629 Third St., and 1428 E. 32nd St., Des Moines, la. BARTH, Herbert E. (Af.1920) Vice-Pres. (for mail) American Blower Coip.. 6000 Russell St., anH 15 E. Kirby, Detroit, Mich. BARTH, John W. (7 1939) (for mail) P. O. Box 169, and 410 N. E. 5th' St.. Fort Lauderdale. Fla. BARTLETT, Amos C. (Af 1919) Mgr.. Htg. and Vtg. Dept, (for mail) B. F. Sturtevant Co., Damon St., Hyde Park, and 30 Hollingsworth Ave.. Braintree, Mass. - BARTLETT, C. Edwin (Af 1922) Pres:, Bartlett ' & Co., Inc., 3223 Arch St., and 3111 W. Coulter St., Philadelphia, Pa. - BARTLEY, Henry E. (Af 1938) Dir. and Works Mgr., Matthews & Yates, Ltd., "Cyclone Works," Swinton. and (for mail) "The Grange." Hospital 'Rd.. Pendlebury. Lancs., England. ' BARTON, Edmund H. (A 1939) Mgr. Htg. Dept, (for mail) Moosomin Hardware, and Box 308, Moosomin, Sask., Canada. BARTON, Jay (Af 1937) Mgr., National Manu facturing & Engineering Co., 628 E. Forest Ave.. and (for mail) Box 221, Detroit, Mich. BASSETT, James W. (A 1938) Sales Engr. (for mail) McQuay. Inc., 2832 E. Grand Blvd., Detroit, and Birmingham, Mich. BASTEDO, Albert E. (Af 1919) Vice-Pres. and Treas., Burnham Boiler Corp., Irvington, N. Y. BASTEDO, George R. (7 1937) Service Mgr.. Thomas Shipley, Inc., York, Pa., and (for mail) 102-36 86th Rd., Richmond Hill, L. I., N. Y. BATES, John H. (5 1939) Service Dept., Sears. Roebuck & Co., 2124 Fairmount St., and (for ' mail) 1013 W. Lehigh St.. Philadelphia, Pa. BAUER, Albert E. (Af 1935) Engr., United States Air Conditioning Corp., 2101 N. E. Kennedy. Minneapolis, and (for mail) 59 S. Vlfctoria St.. St. Paul, Minn. BAUGHMAN, L. R. (Af 1935) Htg. Engr.. Helms & Baughman, 103 N. Sheridan Rd., Waukegan, and (for mail) 2706 Eschol Ave., Zion, 111. . BAUM, Albert L. (Af. 1916) Member of Firm (for mail) Jaros, Baum & Bolles, 415 Lexington Ave.. and 600 West 111 St., New York, N. Y. BAUMGARDNER, C. M. (Af 1928) Mgr., Chicago Branch (for mail) United States Radiator Corp., 3254 N. Kilbourn Ave., Chicago, and 602 Michi gan Ave:, Evanston, 111. BAXTER, William E. (A 1939) Pres, (for mail) W. E. Baxter, Ltd., 87 Vitre, W., Montreal, and 89-51st Ave., Lachine, P. Q., Canada. BAY, Charles H. (A 1938) In Charge of Steam Sales (for mail) The Detroit Edison Co., 2000 Second Ave., and 17323 Wildemere St., Detroit, Mich. ' ' BAYSE, Harry V. (Af l923) Chairman of Board (formail) American Furnace Co., 2719-31 Delmar Blvd., and 6959 Hancock Ave., St- Louis, Mo. BEACH, Walter R. (A 1936) Sales Engr. (for mail) Cleveland Electric Illuminating Co.. 75 Public Sq., Cleveland, and 1185- Yellowstone Rd.. Cleveland Heights,' O. - ` BEAIRD, Benjamin J. (Af 1939) Resident Engr.. Kribs & Landauer (for mail) 331 Bankers Mortgage Bldg.,`and 2505 Hazard, Houston, Tex. BEAN. George S. (A 1935) Mgr., Stoker Div. and Stoker Engr. (for mail) North Western Fuel Co.. E. 1203 First Natl. Bank Bldg., St. Paul, and 4949-l6th Ave., S., Minneapolis. Minn. BEARMAN, Alexander A. (Af 1937) Engr. (for mail) 20th Century-Fox Film Corp., 444 W. 56th St., New York, and 47 Edward St., Baldwin, L. I.. N. Y. . BEAULIEU, Adrian A. (Af 1937) Dist.: Htg. Engr., Boston Edison Co., 39 Boylston St.; Boston, and (for mail) 535 N. Elm "St., W.. Bridgewater, Mass. ' .. BEAURR1ENNE, Auguste* (Af 1912) Consulting Engr. & Expert, 18 Rue du Petit Val, Sucy en Brie, S et O, France. BEAVERS. George R. (Af 1929) Chief Engr.. Canadian Blower & Forge Co., Ltd., -Woodside Ave., and (for mail) 60 Church St.< Apt. "D." Kitchener, Ont.. Canada. BECHTOL, Jack J. (7 1937) Conditioner (for mail) Jos. E. Seagram & Sons, Inc., Lawrence- burg, Ind., and 4766 Rapid Run Pike, Cincinnati. BECKER, C. S. (Af 1939) Branch Mgr: (for mail) American Blower Corp;, 1011 Majestic Bldg., and 4573 W. Bluemound Rd., Milwaukee, Wis. BECKER, Roger K. (Af 1938) Dept. Mgr., Ohio Valley Hardware & Roofing Co., 300*4th Ave.. and (for mail) 1017 E. Powell Ave.. Evansville, Ind. - ` ; 12 ROLL OF MEMBERSHIP BECKER. Walter A. (Af 1935) Sales Engr. (for mail) Grinnell Co., Inc., 4425 S. Western Ave., and 5728 N. Rockwell St., Chicago, III. BEEBE, Frederick E. W. (A 1915) Johnson Service Co., 28 East 29th St.. New York, N. Y. BEERY, Clinton E.* (Af 1913) 3927 Southport Ave., Chicago, III. BEGGS, William E. (Af 1927) Owner, W. E. Beggs Co., 416 Bell St., and (for mail) 3639 Palatine Ave., Seattle. Wash. BEIGHEL, H. A. (A 1927) Sales Repr. (for mail) Herman Nelson Corp., 503 Columbia Bldg.. Pittsburgh, and 207 Puritan Rd., Rosslyn Farms, Carnegie, Pa. BEITZELL, Albert E. (A 1933; 7 1930) Mgr., Air Cond. Div., Combustioneer Corp.. 409 10th St., S. W,, and (for mail) 1213 Hamilton St., N.W., Washington, D. C. BELING, Earl H.* (Af 1936; A 1930; 7 1925) Owner, Beling Engineering Co.. 405 State Trust Bldg., and (for mail) 2428-13th St.. Moline. 111. BELL, E. Floyd (Af 1933) Pres, (for mail) Bell & Eiss, Inc., 2102 Foshay Tower, and 5337 Girard Ave., S.P Minneapolis, Minn. BELL, Sydney R. (Af 1939) Consulting Engr. (for mail) Sydney R. Bell & Associates, 374 Little Collins' St., and 83 Queens Rd., Melbourne. BELSKY, George A. (A 1937) Air Cond. Engr.. Justin C. O'Bnen Co., 734 Lexington Ave., New York, and (for mail) 53 N.`Grove-St., Valley Stream, L. I., N. Y. BELT, Newton O. (Af 1929) Engrg. Dept, (for mail) E. I. Du Pont de Nemours & Co., and 824 West 10th St., Wilmington, Del. BEMAN, Myron C. (Af 1926) (Council 1934-1939) Consulting Engr. (for mail) Beman & Candee, 374 Delaware Ave., and 699 Richmond Ave., Buffalo, N. Y. BENHAM, Colin S. K. (A 1940; 7 1937) Dir. (for mail) Benham & Sons, Ltd., 66 Wigm'ore St.. London W. 1, and 5 Constable Close, London N. W. 11, England. BENHAM, Ford C., Jr. (7 1938) Sales Engr. (for mail) c/o C. H. Ruebeck Co.. P. O. Box 141. and 709-A James St., Waco, Tex. - BENNETT, Charles A. (Af 1936) 1751 Kilbourne Place. N. W., Washington, D. C. BENNETT, Edwin A. (Af 1936; 7 1929) Sales Engr. (for mail) American Blower Corp.. 50 W. 40th SL. New York, and 45 Pondfield Rd.. W.. BronxviHe, N. Y1 BENNITT, George E. (Af 1918) 44 Cedar St.. Wakefield, Mass. ' BENOIST, LeRoy L. (Af 1934) Mgr. (for mail) Benoist Bros. Supply Co., 117 S. Tenth St., and 1500 Main St., Mt. Vernon, 111. BENOIST, Raymond E. (A 1936) Partner, Benoist Bros, and Secy.-Treas., Benoist Bros. Supply Co., 117 South 10th SL, and (for mail) 811 North 12th St., Mt. Vernon, 111. BENSEN. Clarence L. (Af 1939; 7 1935) Chief Engr. (for mail) McQuay, Inc., 1600 Broadway, N.E., and 2722 Benjamin St., N.E., Minneapolis, Minn. BENSINGER, Mark (7 1936) Mech. Engr.(Htg. & Air Cond.) Constr. Div. of Office of the Q.M.G., War Dept., and (for mail) 3718 Jocelyn St.. N. W., Washington. D. C. BENSON, Bernard C. (Af 1937) Salesman (for mail) American Radiator & Standard Sanitary Corp., 816 S. Michigan Ave., and 8127 Clyde Ave., Chicago. III. BENSON, Merrill L. (Af 1938) Mgr., Air Cond. Coil Div. (for mail) McQuay, Inc., 1600 Broad . way, N. E.t and 4521 Harriet Ave., S., Minne apolis, Minn. ' BENTLEY, Clyde E. (Af 1937) Consulting Engr.. 216 Pine St., San Francisco, and (for mail) 1875 San Antonio Ave., Berkeley, Calif. BENTZ. Harry (Af 1915) Htg. & Vtg. Engr., 18 Holland Terrace, Montclair, N. J. BERGAN, John R. (7 1937) Dist. Repr. (for mail) Minneapolis-Honeywell Regulator Co., 1220 Madison St., Toledo, and 525 W. Broadway, Maumee, O. BERGER, J. L. (Af 1939) Vice-Pres. & Secy, (for mail) The W. R. Rhoton Co., 1305 E. 107th SL, and 2652 Edgerton Rd.. Cleveland, O. BERMAN, Louis K. (Af 1908) Pres, (for mail) Raisler Corp., 129 Amsterdam Ave., and 285 Central Park West, New York, N. Y. BERMEL, Alfred II. (A 1933; 7 1928) Estimator and Engr., August Arace & Sons, Inc., 642-3rd Ave., Elizabeth, and (for mail) 16 William St., No. Arlington, N. J. BERNERT, Lawrence A, (A 1937) Branch Mgr. (for mail) Warren Webster & Co., 316 Liberty Trust Bldg., and 610 Maiden Lane. Roanoke, Va. BERNHARD. George (Af 1935; A 1929) State Roofers, 612 Ludington St., P. O. Box 394, Escanaba, Mich. BERNSTROM, Bert* (Af 1930) Consulting Engr. (for mail) B. Bernstrom & Co., 122 W. Kinzie St., and 5843 W. Roscoe St., Chicago, 111. BERR1DGE, Winston W. (Af 1938) Sales Engr. (for mail) McCoIl-Frontenac Oil Co., Ltd., Dominion Square Bldg., and 5169 Westbury Ave., Montreal, P. Q., Chnada. BERRINGER. Sidney H. (Af 1926) Inspector of Engrg. Materia], U. S. Navy, 243 Washington, and (for mail) Hotel Worth, 200 Main St., Buffalo. N. Y. BERRY, Robert U. (Af 1939) DisL Mgr., Air Cond. Dept., General Electric Co. (for mail) 1801 N. Lamar St., and 3925 Bryn MawrSt., Dallas. Tex. BERTRAND, G. F. (A 1939) Mgr., Universal Air Cond. Co.. Market St. Natl. Bank Bldg., Philadelphia, and (for mail) 235 Richfield Rd., Upper Darby, Pa. fJERZELIUS, Carl E. (Af 1936) Captain, Com manding Officer, CCC Camp, and (for mail) 101-Wisconsin. Neodesha, Kan. BETLEM, Henriette T. (7 1934) Air Cond. Engr. (for mail) Betlem Heating Co., 1926 East Ave., and 1293 Park Ave., Rochester, N. Y. BETTS, Howard M. (Af 1927) Sr. Mech. Engr.. Htg. & Vtg. (for mail) Dept, of Buildings, City of Minneapolis, 213 City Hall, and 4923 S. Russell Ave., Minneapolis, Minn. BETZ, Harry D. (Af 1928) Pres., Betz Air Con ditioning Corp., 1820 Wyandotte SL. and (for mail) 1610 Valentine Rd., Kansas City, Mo. BEVINGTON, Curtis H. (Af 1936) Mgr. (for mail) C. H. Bevington Co., 600 S. Michigan Ave., Chicago, and Park Ridge, III. BIANCULLI, Vincent A. (7 1937) Draftsman, Navy Yard. Brooklyn, and (for mail). 557 Broome St., New York, N. Y. BIBER, Herbert A. (A 1937) Engr. (Htg., Air Cond. Refrigeration) Mellon National Bank, 514 Sraithfield St., Pittsburgh, and (for mail) 323 Barnes St.. Wilkinsburg/Pa. BICHOWSKY, F. Russell (Af 1935) Consulting Engr. (for mail) Dow Chemical Co., 309 S. State St., and 1508 Granger, Ann Arbor, Mich. BIERINCER. Fred A. (7 1939) Asst. Chief House heating Engr., Brooklyn Borough Gas Co.. Mermaid Ave. & 17th St., and (for mail) 4017Gth St., Brooklyn, N. Y. BIGELOW, Edward S. (Af 1938) Mgr., Air Cond. Dept., Dravo Corp., 300 Penn Ave., Pittsburgh, and (for mail) 413 Jericho Rd., Montgomery Co., Abington, Pa. . BIGGERS, Richmond H. (A 1939) Mfrs. Agent (for mail) 2217 E. Jefferson Ave.. and 2237 E. Jefferson Ave., Detroit, Mich. BIGOLET, Louis (Af 1939) Owner, Plumbing & Heating, 40 New Chambers St., New York, and (for mail) 1145 Ocean Parkway, Brooklyn, N. Y. BILLINGSLEY, Oliver F., 2nd (7 1937) Experi mental Engr., Vitasphere Research Inst.,- Holly wood, and (for mail) 1682 W. 25th St., Los Angeles, Calif. BINDER, Charles G. (Af 1920) Mgr., Htg. Dept.. Warren Webster & Co., 17th & Federal St., Camden, and (for mail) 115 Oak Terrace, MerchantviUe, N. J. BIRD, Charles (A 1934) Treas. & Gen. Mgr. (for mail) The Doermann Roehrer Co., 450 E. Pearl St., and Box 179. D Section Rd.. R. R. No.: 6, . Cincinnati, O. 13 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 BIRD, George L H. (J 1937) Chief Engr. (for mail) Refrigeration & Allied Products. Ltd.. 92 Buckingham Palace Rd.. London, 5. W. 1. and 12 Lawn Rd., London, N. W. 3. England. BISHOP, Charles R. (Life Member\ M 1901) 22 Sagamore Rd., Bronxville, N. Y. BISHOP, Frederick R. (M 1921) Mgr. of Sales. The Brundage Co., Kalamazoo, and (for mail) 8011 Dexter Blvd., Detroit, Mich. BISHOP, J. A. (M 1939) Dist. Mgr. (for mail) American Blower Corp., 619 Mercantile Bldg., and 1115 N. Windomere, Dallas, Tex. BISHOP, Joseph W. (M 1939) Mgr. Air Cond. Div., Toronto Dist. (for mail) Canadian General Electric Co., Ltd., 214 King St., W., Toronto, and 62 Highland Crescent, York Mills, Ont., Canada. BISHOP, Marion W. (A 1939: J 1935) Sales Engr. (for mail) American Blower Corp., 228 N. LaSalle St., and 7024 Sheridan Rd., Chicago, 111. BJERKEN. Maurice H. (M 1937; A 1927) Sales Engr., Hoffman Specialty Co., 533 S. 7th St., and (for mail) 4952-l7th Ave., S., Minneapolis, Minn'. BLACK, Edgar N., 3rd (M 1922) Philadelphia Mgr. (for mail) Fitzgjbbons Boiler Co.. Inc., Rm. 502, Presser Bldg., Philadelphia, and 111 Woodside Rd., Haverford, Montgomery Co., Pa. BLACK, F. C. (Life Member; M 1919) Pres, (for mail) F. C. Black Co., 622 W. Randolph SL, and 4535 N. Ashland Ave., Chicago. 111. BLACK, Frank M. (A 1937) Chief Engr.. U. S. Government. Army Medical Center, Washington, D. C., and (for mail) P. O. Box 164, Silver Spring, Md. ' BLACK. Harry G. (M 1917) Prop, (for mail) P. Gormly Co.. 155 N. 10th St., and 927 N. 65tb St., Philadelphia, Pa. BLACK, James M. (J 1940; 5 1939) Sales Engr., Avery Engineering Co., 2341 Carnegie, Cleve land, and (for mail) 2483 Canterbury Rd., Cleveland Heights, O. BLACKBURN, E- C., Jr. (M 1929) Mech. Engr., Crow, Lewis & Wick, Archts., 200 Fifth Ave., New York, and (for mail) 5 Kenwood Rd., Garden City, L. I-, N. Y. BLACKHALL, W. R. (M 1922) Partner (for mail) McKeller & Blackball, 1104 Bay St., and 332 Waverly Rd., Toronto, Ont., Canada. BLACKMAN, Alfred O. (M 1911) Htg. and Vtg. Engr. (for mail) c/o Robert & Co., Atlanta, Ga.. and 450 W. 24th St., New York, N. Y. BLACKMORE, F. H. (M 1923) Mgr., Mfg. Dept, (for mail) U. S. Radiator Corp., 1056 Natl. Bank Bldg., Detroit, and 515 Tooting Lane. Birming ham, Mich. BLACKMORE, George C. (Charter Member; Life' Member) Pres, (for mail) Automatic Gas Steam Radiator Co., 301 Brushton Ave., and Cathedral Mansions. Pittsburgh, Pa. BLACKMORE, J. J.* (Charter Member; Life Mem ber) 32 West 40th St., New York, N. Y. BLACKMORE, Joseph J. (A 1939; J 1937) Sales Engr., Mfrs. Agency, 6327 Clayton Ave., St. Louis, and (for mail) 312 S. Fillmore, Edwards- ville, III. BLACKSHAW. J. L * (M 1937; J 1929) Branch Mgr., Air and Refrigeration Corp., 268 Mc Donough Blvd.. Atlanta, and (for mail) 247 W. Mercer Ave., College Park, Ga. BLAKELEY, Hugh J. (M 1935) Consulting Engr. (for mail) Hubbard Rickerd & Blakeley, Con sulting Engrs., 110 State St., Boston, and 145 Greaton Rd., West Roxbury, Mass. BLAKER, Alfred H. (A 1939) Secy. & Treas. (for mail) National Korectaire Co., 1619 Cortland St., and 6018 N. Francisco Ave., Chicago, 111. BLANDING, Robert L. (M 1938) Vice-Pres. (for mail) Taco Heaters, Inc., 123 South St., and 1385 Smith St., Providence, R. I. BLANKIN. Merrill F. (M 1927; A 1926: J 1919) (Treas., 1939; Council, 1939) Pres. (lor mail) Haynes Selling Co., Inc., S. E. Cor. Ridge Ave., and Spring Garden St., and 528 E. Gates St., Roxboro, Philadelphia, Pa. BLAS, Romualdo J. (Jf 1936) Mgr. & Chief Engr., Bias & Co., Apartado Postal 1006, Caracas, Venezuela, South America. BLAYNEY, W. Ronald (A 1939) Secy. & Treas.. W. B. Graves Heating Co., 162 N. Desplaines St., and (for mail) 4327 Monticello Ave., Chicago, III. BLEDSOE, Raymond P. (A 1940; J 1937) Sales Engr. & Estimator, Reinick & Krueger, 106 N. Frances, and (for mail) 530 N. Pinckney St., Madison. Wis. BLIZZARD. Bruce C. (A 1939) Asst. Mgr. Fuel Oil Dept, (for mail) Imperial Oil, Ltd., 56 Church St., and 1 Mallory Gardens, Toronto, Ont., Canada. BLOOM, Louis (M 1935) Partner, Freeport Plumbing and Heating Engineers, 84-A, Broad way, Freeport, L. 1., N. Y. BLUM, Herman, Jr. (J 1936) Mech. Engr., C. Wallace Plumbing Co., Box 1209, and (for mail) 3909 Bryn Mawr St., Dallas. Tex. BLUMENTHAL, M. I. (M 1936) Engr. in Charge Refr. & Air Cond. (for mail) National Schools, 4000 S. Figueroa, and 648 W. Santa Barbara. Los Angeles, Calif. - BOALES, William G. (M 1936; A 1923) Owner (for mail) Win. G. Boales & Associates, 6439 Hamilton Ave., Detroit, and 195 McMillan Rd., Grosse Point Farms, Mich. BOCK, 1.1. (A 1934) Pres, (for mail) Carrier-Bock Corp.. 2022 Bryan St., and 2500 South Blvd., Da|jas BODEN,' waiter F. (A 1937) Branch Mgr. (for mail) Modine Mfg. Co., 420 E. Wells St., Mil waukee, and 606 Milwaukee Ave., South Mil waukee, Wis. BODINGER, Jacob H. (M 1931) Pres, (for mail) Bodinger & Co., Inc.. 530 Tenth Ave., New York, ' and 1429 East 19th St., Brooklyn, N. Y. BODMER, Emmanuel (M 1937) Engr., Head of Tech. Dept., Ets. Dieny & Lucas, 223 Boulevard Pereire, and (for mall) 20. rue Leon, Paris (l8e) France. ` BOESTER, Carl F.t Jr.* (M 1939; A 1936) Air Cond. Engr., 101 E. Essex, Kirkwood, St. Louis, Mo. BOGATY, Hermann S. (M 1921) 735 E. PhilElJena St.. Philadelphia, Pa. BOLAND, Roy O. (A 1938) Mgr., Insulation Div. (for mail) Alexander Murray & Co., Ltd., 4035 Richelieu St., Montreal, and 348. Kensington Ave., Westmount, P. Q., Canada. BOLTON, Reginald P.* (Honorary Member; Life Member; M 1897) (Presidential Member) (Pres. 1911; 1st Vice-Pres, 1905-1910; 2nd Vice-Pres. 1903; Board of Governors, 1901,1905.1910,1911, 1912, 1913) The R. P. Bolton Co., 116 East 19th St., New York, N. Y. BOND, Harry H. (AT 1938) Partner (for mail) Edward E. Ashley, Cons. Engr., 10 East 40th St., New York, and 141-49 181st St., Springfield. L. 1.. N. Y. BOND, Horace A. (M 1930) Dist. Mgr., Warren Webster & Co., 152 Washington Ave., and (for mail) 12 Ramsey PI., Albany, N. Y. BONTHRON, Robert C. (A 1935) Syndicate Repr., Air Cond. Dept., Westinghouse Electric & Mfg. Co., 150 Broadway, New York, and (for mail) 44 Ingraham Blvd., Hempstead, L. I., N. Y. BOOT, Arthur (M 1938) Mgr., Air Cond. Div. (for mail) Boot & Co., 115 W. Fulton St., and 928 Orchard Ave., S. E., Grand Rapids, Mich. BOOTH, Charles A. (M 1917) Vice-Pres. & Sales Mgr. (for mail) Buffalo Forge Co., 490 Broadway, and 142 Summit Ave., Buffalo. N. Y. BORAK, Eugene (M1937) Engr., Buensod-Staccy Air Cond., Inc., 60 East 42nd St., New York, N. Y., and (for mail) 261 Manhattan Ave.. Jersey City, N. T. BORG, Elmer H. (M 1938) Partner (for main Proudfoot Rawson-Brooks & Borg, Archts., 815 Hubbell Bldg., and 3101 Easton Blvd., Dcs Moines, la. BORKAT, Philip (J 1936) Asst. Engr., U. S. Dept, of Agriculture, Washington, D. C., and (for mail) 900 Kennebec Ave., Takoma Park, Md^ BORLING, John R. (A 1934) Engr.-Custodian (for mail) Chicago Board of Education 214 N. Lavergne Ave., and 1000 N. Waller Ave., Chicago, 111. , 14 ROLL OF MEMBERSHIP BORNEMANN, Walter A, (M 1924; J 1923) Sales Engr. (for mail) Carrier Corp., 12 South 12th St., Philadelphia, and 123 W. Wharton Ave., Glenside, Pa. BORNSTEIN, William (A 1937) Partner (for mail) Win. Bornstein & Son, 720 New Jersey Ave., N. W., Washington, D. C., and 222 Chestnut Ave., Takoma Park, Md. BORTON, A. Robert (J 1939) Branch Mgr. (for mail) John J. Nesbitt, Inc., 720 Empire Bldg., and 1144 Tennessee Ave. (Dormont) Pittsburgh. Pa. BOTELHO, Nanto J. (A 1937) Engr. and Mgr., Ceibrasi! Represenlacoes Ltda., Rua General Camara, 64-70 andar, Rio de Janeiro, Brazil, South America. BOTTUM, Edward W. (J 1938) Research Engr., Copeland Refrigeration Corp., Sidney, and (for mail) 223 High St., Piqua, O. BOUEY, Angus J. (A 1937; J 1930) Sales Engr., (for mail) The B. F. Sturtevant Co., 681 Market St., and 4810 Fulton St., San Francisco, Calif. BOUILLON, Lincoln (M 1933) Consulting Engr. (for mail) 1411 Fourth Ave. Bldg., and 2211 32nd South, Seattle, Wash. . BOWEN, John C. (A 1938) Dist. Repr., Lennox Furnace Co. (for mail) 1917 Elm St., Denver, Colo. BOWERMAN, Everett L. (A 1937) Sales Engr. Canadian Ice Machine Co., Ltd.. Eastern Harbour Terminals, and (for mail) 274 Belsize Dr., Toronto, Ont., Canada. BOWERS, Arthur F. (A 1919) Pres, (for mail) Industrial Heating & Engineering Co., 828 N. Broadway, and 2853 N. Hackett Ave., Milwau kee, Wis. BOWLES, Edmund N. (A 1937) Northwest Air Cond. Supvr. (for mail) Westinghouse Electric Sl Mfg. Co., 20 N. Wacker Drive, and 6043 N. Paulina St., Chicago, 111. . BOWLES, Potter (A 1928) Pres, (for mail) Hoffman Specialty Co., Inc., 575 Pacific St., Stamford, and Box 61. New Canaan, Conn.- BOXALL, Frederick (M 1937) Mgr., Air Cond. Dept, (for mail) J. H. Vivian Co., Ltd., Box 301, Johannesburg, South Africa. BOYAR, Sidney L. (J 1937) Estimating Supvr., Sears Roebuck & Co., 925 S. Homan Ave., Chicago, and (for mail) 853 Wentworth Ave., Calumet City, 111. BOYD, Spencer W. (M 1937; / 1931) Consulting Engr. (for mail) Newcomb & Boyd, Trust Co. of Georgia Bldg., and 1505 Fairview Rd., Atlanta, Ga. BOYD, Thomas D. (M 1937) Sales Engr. (for mail) Johnson Service Co., 1113 Race St., and 3332 North Sterling Way, Cincinnati, O. BOYDEN, Davis S.* (Life Member; M 1909) (Pres. 1937; 1st Vice-Pres. 1936: Treas., 1933-1934; Council, 1917, 1930-1938) Consultant, Goodrich St., Lunenburg, and (for mail) Box 386, Shirley, Mass. ' BOYKER, Robert Owen (J 1935) Contractor. Mac Boyker & Son (for mail) 220 1st Ave., and 100 Kennebeck Ave., Kent, Wash. BOYLE, John R. (M 1936) Traveling Sales Mgr.. Westerlin & Campbell Co., 1113 Cornelia Ave., and (for mail) 6858 Osceola Ave., Chicago, 111. BOZEMAN, Richard (M 1936; J 1929) Pro duction Supt., United Clay Products Co., 931 Investment Bldg., Washington, D. C., and (for mail) 1706 N. Uhle St., Arlington, Va. BRAATZ, Chester J.* (M 1930) Sales Mgr., Temperature Control and Uni-Flo Dept, (for mail) Barber-Colman' Co., and 1819 Clinton St., Rockford, 111. ' BRACKEN, John H. (M 1927) Mgr., Industrial Uses Dept, (for mail) The Celotex Corp., 919 N. Michigan Ave., and 455 Oakdale Ave., Chicago, 111. BRADFIELD, William W. (M 1926) Mech. Engr. (for mail) 341 Michigan Trust Bldg., and 1352 Franklin St., S. E., Grand Rapids, Mich. BRADFORD, Gilmore G. (M 1936) Mgr., Frigidaire Div., General Motors China Ltd., 201 Rte. Cardinal Mcrcier, Shanghai. China. BRADLEY, Eugene P. (M 1906) Pres, (for mail) Hester-Bradley Co., 2835 Washington Blvd., and No. 4 Yale Ave., St. Louis, Mo. BRADLEY, J. M. (A 1938) Chicago Repr. (for mail) Airtherm Mfg. Co., 312 N. Loomis St., and 1352 Astor St., Chicago, III. BRANDI, O. H. (M 1930) Dipl. Ing. Rud. Otto Meyer, Hamburg 23, and (for mail) Reinbek b. Hamburg, Hamburgerstr 14, Germany. BRANDT, E. H.. Jr. (M 1928) Pres, (for mail) Reliance Engineering Co., Inc., P. O. Box 1292, and 1101 Providence Rd., Charlotte, N. C. BRANIFF, Paul R. (A 1939) Mgr., Braniff Engineering Co., 817 N. Broadway, Oklahoma City, Okla. BRASHAW, Clarence J. (A 1938) Sales Engr. (for mail) J. F. Stampfer Co., 800 Main SL, and 765 Chestnut St., Dubuque, la. BRATT, Hero D. (M 1937) Sales Engr., Warren Webster & Co., 228 Ottawa Ave., and (for mail) 2259 Stafford Ave., Grand Rapids, Micb. . BRAUER, Roy (M 1926) Mgr., Pittsburgh Office (for mail) The Trane Co., Magee Bldg., and 576 Austin Ave., Mt. Lebanon, Pittsburgh, Pa. BRAUN, Charles R., Jr. (S 1939) Student (for mail) Carnegie Institute of Technology, Pitts burgh, Pa., and 845 Thomas Rd., Columbus, O. BRAUN, John J. (M 1932) Factory Mgr., The United States Playing Card Go., Cincinnati, and. (for mail) 4305 Floral Ave., Norwood, O. BRAUN, Louis T. (M 1921) Executive Secy, (for mail) Chicago Master Steamfitters Assn., 228 N. LaSalle St., and 1548 Pratt Blvd., Chicago^ 111. BRAYMAN, Albert I. (J 1937) Draftsman and Estimator, Edward Brayman. Htg. Contractor, 81 Chamber SL, Boston, and (for mail) 340 Boulevard, Revere, Mass. BRECKENRIDGE, L. P.* (Honorary Member; Life Member; M 1920) Prof, of Mech.. Eagrg., Emeritus Yale University (for mail) '"The Brackens," North Feirisburg, Vt. BREDESEN. Bernhard P. (A 1931) Engr. (for mail) Reese & Bredesen, 403 Essex Bldg., and 3319 Knox Ave., N,, Minneapolis, Minn. BRENEMAN, Robert B. (A 1931; J 1927) Branch Mgr. (for mail) Armstrong Cork Co., 37 N. 3rd St.. Columbus, and Rte. 2, Westerville, O. BREX, Irving E. (A 1939) Asst. Secy. & Treas. (for mail) Brex & Bieler Div., The Excelsior Steel Furnace Co., 45th St. & 1st Ave., and 533-76th St., Brooklyn, N. Y. BRIDE, WUUam T. (M 1928; J 1925) Supt. Engrg., Bride-Grimes & Co., 9 Franklin St. (for mail) P. O. Box 777, Lawrence, and 28 Albion St., Methuen, Mass. BRIERLY, Keppel (A 1939; J 1938) Coordinator & Cons. Engr., Denver Public Schools, Oppor tunity School, 13th & Welton Sts., and (for mail) 1378 Dexter St., Denver, Colo. BRIGHAM, Clare M. (M 1935) Vice-Pres. in Charge of Sales (for mail) C. A. Dunham Co., 450 E. Ohio St., Chicago, and 420 Maple Ave., Winnetka, ill. BRINKER, Harry A. (M 1934) 2521 University Ave., Kalamazoo, Mich. BRINTON, Joseph W. (M 1920) Mgr., Boston Dist. (for mail) American Blower Corp., 1003 Statler Bldg., Boston, and 42 Gleason SL, West Medford. Mass. . BRISSENDEN. Carroll W. (J 1939) Htg. Engr.. Portland General Electric Co., Portland (for mail) Box 108 and 7424 S. W. 25th, Multnomah, Ore. BRISSETTE, Leo A. (M 1930) Treas. (for mail) Trask Heating Co., 4 Merrimac St., Boston, and 168 Florence St., Melrose, Mass. - BRITTAIN, Alfred, Jr. (M 1938) Engr., Weather- makers (Canada) Ltd., 593 Adelaide St., and (for mail) 138 Wheeler Ave., Toronto. Ont., Canada. BROCHA, John F. (M 1936) Buyer of Plbg. and Htg., Montgomery Ward & Co., 619 W. Chicago Ave., and (for mail) 5475 Hirsch SL, Chicago, IU. BROCKINTON, C. E. (A 1937) Sales Engr. (for mail) Advanced Refrigeration. Inc., 350 Peach tree St., and 734 Frederica St., N. E., Apt. 9, Atlanta, Ga. 15 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 BRODERICK, Edwin L.* (Af 1933) Research Asst, in Mech. Engrg. (for mail) University of Illinois. 213 M. E. Lab.. Urbana, and 909 S. First St.. Champaign. 111. BRODNAX, George H., Jr. (At 1938) Sales Engr. (for mail) Georgia Power Co.. Electric Bldg.. 75 Marietta St.. N. W., and 1564 Westwood Ave., S. W., Atlanta, Ga. BROKAW, George K. (/ 1939; S 1938) Office Engr., Clyde E. Bentley. Cons. Engr.. 216 Pine St.. San Francisco, and (for mail) 2424 S. Ather ton St., Berkeley, Calif. , BRONSON. Carlos E.* (Af 1919) Chief Mech. Engr., Kewanee Boiler Corp.. Kewanee, III. BROOKE. Irving E. (Af 1937) Consulting Engr. (for mail) 189 W. Madison St.. Chicago, and 830 Keystone Ave., River Forest. 111. * BROOM. Benjamin A. (Af 1914) Sales Pro motion Engr., Weil-McLain Co., 641 West Lake St., and (for mail) 1534 Fargo Ave., Chicago. 111. BROOME, Joseph H. (A 1936) Sales Engr., Minneapolis-Honeywell Regulator Co., 604 Cen tral Ave., East Orange, and (for mail) 89 Edge- mont Rd., Montclair, N. J. ' BROWN, Alfred P. (Af 1927) Vice-Pres. (for mail) Reynolds Corp., 1400 Wabansia Ave., Chicago, and 439 Maple St., Winnetka, 111. BROWN, Aubrey I.* (Af 1923) Prof, of Htg. and Vtg. (for mail) Ohio State University, and 169 Richards Rd., Columbus, O. BROWN, David (Af 1936) Owner (for mail) 67 Cooper Square, and 54 West 174th St., New York. N. Y. ^ BROWN, Foskett* (Af 1926) Pres, (for mail) Gray & Dudley Co., 222 Third Ave.. N.. and 2314 West End Ave., Nashville, Tenn. BROWN, John S., Jr. (J 1937) Sales Engr,. Smith Distributing Co., and (for mail) 2230 Talbott Ave.. Louisville. Ky. ,, ._ BROWN, Joy S. (Af 1938) Mgr., Air Cond. Dept, (for mail) J. P. Baldwin Co., 1304 W. Washington Blvd., and 5760 E. Circle Ave., Chicago, 111. BROWN, Mack D. (At 1938; J 1936) Mech. Engr., Htg. and Vtg. (for mail) Northup & O'Bnen, Archts., 602-03 Reynolds Bldg., and 915. East 21st St., Winston-Salem, N. C. BROWN, Marvin L. (Af 1939) Vice-Pres.. Dallas Air Conditioning Co.. Inc., 3500 Commerce St., and (for mail) 3461 Potomac St., Dallas, Tex. BROWN, Maurice W. (J 1938) Sales Engr. (for mail) American Blower Corp., 619 Mercantile Bldg., and 1201 E. 7th, Dallas. Tex. BROWN, Sterling D. (J 1939) Office Mgr. & Sales Engr. (for mail) The Trane Co., S-162 Lincoln, and E-930-l6th, Spokane, Wash. BROWN, Tom (At 1930) Vice-Pres. & Gen. Mgr. (for mail) Autovent Fan & Blower Co.,.1805-27 N: Kostner Ave., and 5325 N. Laramie Ave., Chicago, III. _ BROWN, William H. (A 1923) Mgr.. Brown Bros., Inc., 3015 North 22nd St., Milwaukee. Wis. BROWN, W. Maynard (A 1930) Warren Wesbter & Co., 17th and Federal Sts., Camden, N. J. BROWNE, Alfred L. (Af 1923) 253 Highland Ave., ` South Orange, N. J. BRUNETT, Adrian L. (Af 1923) Mech. Engr., U. S. Supervising Architects Office, Treasury Dept.; Washington, D. C., and (for mail) P. O. Box 36, Rockville, Md. BRUST, Otto (Af 1930) Consulting Engr;, Wil- mersdorferatrasse 95,1 Berlin-Charlottenburg. 4, Germany. ; - - J BRYANT, Alice Gertrude*, A.B..M.D..F.A.C.S., AS-E.E. (Life Member; At 1921) Otolaryngologist Physician and Surgeon, 405 Marlborough St., Boston, Mass. - BRYANT, Percy J. (Af 1915) Chief Engr. (for mail) Prudential Insurance Co. >of America, 763 Broad St., Newark, and 754 Belvidere Ave.. Westfield, N. J. ' BUCK,-David T. (A 1936) Pres, (formail) Buck Engineering Co., 37-41 Marcy St., and 116 W. Main St., Freehold, N. J. BUCK, Luclen (Af 1928) Engr., Proctor & Schwartz. Inc.,7thSt.&TaborRd., Philadelphia, and (for mail) Pardee Lane, Wyncote, Pa. BUCKER1DGE, Victor L. (A 1938) Partner (for mail) H. Buckeridge & Son, 15108 Kerchival Ave., Grosse Pointe Park, and 601 Fisher Rd., Grosse Pointe, Mich. BUCKLEY, Duane J (S 1939) Student, Uni versity of Illinois, Urbana, 111., and (for mail) 421 S. Fountain, Wichita, Kan. BUCKLEY. Malcomb L. (A 1939) Estimator (for mail) PhiUips-Getschow Co., 32 W. Hubbard St., and 4542 Beacon St.. Chicago, 111. BUENGER, Albert* (Af 1920; J 1917) (Council. 1934-37) Mech. Engr. (for mail) A. M..Kinney. Inc., Cons. Engrs., 1820 Carew Tower, and 3171 Portsmouth Ave., Cincinnati, O. BUENSOD, Alfred C. (Af 1918) Pres., Buensod- Stacey Air Conditioning, Inc., 60 East 42nd St., and (for mail) 33 Fifth Ave., New York, N. Y. BULLER, Charles R. (A 1938) Chifef Engr., Htg. Equip. & Water System Div., The Heil Co., 3000 W. Montana Ave., and (for mail) 2650 S. Shore Drive Milwaukee, Wis. BULLOCK, Howard H. (A 1933) Commercial Engr. (for mail) General Electric Co., 212 No. Vignes St., Los Angeles, and 2442 Cudahy St., Huntington Park, Catif. , BURCH, Laurence A. (Af 1934) Sales Mgr., R. L. Deppmann Co., 957 Holden Ave., Detroit, and (for mail) 78 Amherst Rd., Pleasant Ridge Royal Oak, Mich. BURGES. Joseph H. M. (J 1939) Willard Ave., Bloomfield, N. J. BURKE, James J. (Af 1939; A 1937j J 1930) . American Viscose Corp., Wilmington, Del.' BURKHART, Elder M. (A 1940: J 1935) Sales Engr., Overly Mfg. Co., 410 Bond Bldg., 14tb St. & New York Ave., N. W., and (for mail) 1631 Montague St., N. W., Washington, D. C. BURNAM, C. M., Jr. (Af 1938; A 1937) Engrg. Editor (for mail) Heating, Piping and Air Con-, ditiooing, 6. N. Michigan Ave., and 10563 S. Hale Ave., Chicago, 111. BURNETT, Earle S. (Af 1920) Senior Mech. Engr., Petroleum and Natural Gas Div., U. S. Bureau of Mines, Amarillo Helium Plant, P. O. Box 2250, and (for mail) 4223 W. Eleventh Ave., Amarillo, Tex. BURNS, Edward J. (Af 1923) Harris Bros. Plumb ing Co., 217 W. Lake St., and (for mail) 4716 Aldrich Ave., Minneapolis, Minn. BURNS, Harold J. (/ 1939) Asst. Htg. Engr.. Washington Gas Light Co., 411-10th St., N. W., and (for mail) 2039 Rosemont Ave., N. W., Washington, >. C. BURNS, John R. (/ 1936; S 1933) Htg. Dept.. Crane Co., 279 Madison Ave., New York, N. Y. and (for mail) 504 N. Main St., Wallingford; Conn. BURR, Griffith C. (Af 1937) Air Cond. Engr.. Air Conditioning Corp., 357 N. Elm St., and (for mail) 808 Cypress St., Greensboro, N. BURR, Kimball (A 1936) (for mail) American Radiator & Standard Sanitary Corp., 3251 Wilshire Blvd., Los Angeles, and 512 N. Maple Dr.. Beverly Hills, Calif. BURRITT, Charles G. (A 1916) Mgr., Minne apolis Office (for mail) Johnson- Service Co., 92 2nd Ave., S., and Leamington Hotel, Minne- . apolis, Minn. . : ' BURTON, W. Russell (A 1939) Engr;, H. J. Sandberg. 500 N. E. Umon Ave;, and' (for mail) 2816 N. E. 19th Ave., Portland, Ore. ` BUSHNELL, Carl D. (A 1921) . Pres. (for. mail) The Bushnell 'Machinery Co.,-.3111 Ross St., Pittsburgh, anil 94 Pilgrim Rd., Rosslyn Farms, Carnegie, Pa. .; BUSSE, Herbert (At 1938) Chief Engr., Fisher & Co., Fisher Bldg. Div., W. Grand Blvd., and (for mail) 16771 Burgess, Detroit, Mich. . - BUTLER, Peter D. (Af 1922) Salesman, U. S. Radiator Corp., Detroit, Mich., and (for mail) 127 Edgewater Rd., Cliffside Park,.N. J.s . BUTT, Roderick E. W. (A 1936; J 1930) 605 Beatty House, Dolphin Square, London, S. W; l. England. ' 16 ROLL OF MEMBERSHIP BUZZARD, Francis H. (Af 1939) Charles S. Leopold. Cons. Engr., 213 S. Broad St., Phila delphia. Pa., and (for mail) 624 Wood Lane, Haddonfield, N. J. ' BYRD, Tom (A 1936) Market Development Div. (for mail) The American Rolling Mill Co., and 2403 Fleming Rd., Middletown, O. BYRNE, Joseph J. (A 1939) Htg. Engr. (for mail) Mueller Furnace Sales Co.. 1836 N.` E. 7th Ave., and 6414 N. E. Rodney, Portland. Ore. BYSOM, Leslie L. (Af 1915) Mech. Engr., Puget Sound, Navy Yard, P.S.N.Y., Public Wks. Dept., and (for mail) 1214 8th St., Bremerton, Wash. c CABOT, Mathew A. (A 1940; J 1937) Mech. & Elec. Engr. (for mail) College of Engineering, University of Kentucky, and Mariemont Dr., Lexington, Ky. CADY, Edward F. (J 1937) Engr., 1003 Euclid Ave., Syracuse, N. Y. CALDWELL, Arthur C. (Af 1930) Engr. and Estimator, P. Gormly Co., 155 N. Tenth St., and (for mail) 550 South 48th St., Philadelphia, Pa. CALEB, David (Af 1923) Engr. (for mail) Kansas City Power & Light Co., 1330 Baltimore Ave., and 141 Spruce St., Kansas City, Mo. CALL, Joseph (Af 1938; / 1936) Air Cond. Engr.. Elliott-Lewis Co., 2518 N. Broad St., and (for mail) 669 Jamestown St.. Roxborough, Phila delphia, Pa. ' CALLAHAN, Peter J. (At 1934) Inspecting Engr., Central Hanover Bank & Trust Co., 60 Broad way, New York, and (for mail) 4057 Amboy Rd., Great Kills, Staten Island, N. Y. CALVER, Robert W. (A 1937) Prop., Plbg. & Htg. Contractor (for mail) P. O. Box 832, and 77 Queen St., Kirkland.Lake, Ont., Canada. CAMERON, Robert T. (`5 1938) Sales Dept.. Crane Co., 4906 Ellis Ave., Chicago, 111., and (for mail) 98 Herrick Rd., Southampton, L. I., N. Y. CAMERON, William R. (A 1936) Dist. Mgr., L. J. Mueller Furnace Co.. Milwaukee, Wis., and (for mail) 3337 Highland Ave., Kansas City, Mo. CAMPBELL, Alfred Q., Jr. (A 1940; J 1933) Engr., E. K. Campbell Heating Co.,, and (for mail) P. O. Box 365, Nashville, Tenn. CAMPBELL, Andy O. (J 1939) Engr. (for mail) Oklahoma Gas & Electric Co., Room 408. 3rd & Harvey, and 2749 N. W. 21st St., Oklahoma City, Okla. . CAMPBELL, Bowen (Af 1938) Engr. (for mail) Campbell Heating Co., 3127 Dean Ave., and 2404 E-. 29th, Des Moines, la. CAMPBELL, Everett K.* (At 1920) (Council. 1931-1933. 1939) Pres, (for mail) E. K. Campbell Heating Co., 2445 Charlotte St., and 3717 Harrisdn, Kansas City, Mo. . CAMPBELL. E. Klrker, Jr. (Af 1938; J 1930) Secy, (for mail) E. K. Campbell Heating Co., 2445 Charlotte St., and 3717 Harrison, Kansas City, Mo. CAMPBELL, Frank B. (A 1927) Mfrs. Agent, 612 W. Franklin St:, Richmond, Va. CAMPBELL, George S. (J 1937) Sales Engr., John Bouchard & Sons, and (for mail) 1100 17th Ave., S., Nashville, Tenn. .' . . CAMPBELL, George W. (/ 1939) Air Cond. Engr., T. H. Urdahl, Cons. Engr., 726 Jackson PI., N. W.. and (for mail) 2300-19th St., N. W., Washington, D. C. : ' CAMPBELL, Ralph L. (.4 1937) Sales Engr., Chrysler Airtemp, 1316 Nicollet Ave., S., and (for mail) 5241 Knox Ave., S., Minneapolis, Minn. CAMPBELL, Robert E. (A 1940; / 1935; 5 1934) Engr., Alfred L. Hart, Inc., 164-07 Hillside Ave., ' Jamaica,, and (for mail) 3520 Newkirk Ave., Brooklyn, N. Y. . CAMPBELL, Roger P. (J 1939) Sales Engr. (for mail) E. K. Campbell Heating Co., 2445 Char lotte St., and 3717 Harrison Blvd., Kansas City, Mo. CAMPBELL, Thomas F. (Af 1928) (for mail) T. F. Campbell Co., 1013 Penn Ave., and R. D. No. 1, Wilkinsburg, Pa. CANDEE, Betram C. (Af 1933) Partner, Beman & Candee, 374 Delaware Ave., Buffalo, and (for mail) 19 Tremont Ave., Kenmore, N. Y. CANON, Herbert A. (A 1938) Sales Engr. (for mail) United Clay Products Co., Carrier Div., 931 Investment Bldg., Washington, D. C,, and 8140 Dale Dr., Silver Spring, Md. CAPLE, Ira (S 1938) Grad. Student, University of Minnesota, Engrg. Experiment Sta., Minneapolis, Minn. CAPPS, Edgar Lee (A 1937) (for mail) Colonial Sales Co., 619 W. 35th St., and 619 Pennsylvania Ave., Norfolk, Va. CARBONE, James H. (At 1937) Htg.-Vtg. In spector, City of New York, New York, and (for mail) 121-13 198th St.. St. Albans, L. I., N. Y. CAREY, Paul C. (Af 1930) Consulting Engr. and Member of Firm (for mail) Runyon & Carey, 33 Fulton St., Newark, and 31 Claremont Drive, Maplewood. N. J. CARLE, William E. (M 1926) Pres, (for mail) Carle-Boehling Co., Inc., 1641 W. Broad St., and 4015 W. Franklin St., Richmond, Va. CARLOCK, Marion F. (Af 1936) Dist. Repr., American Foundry & Furnace Co., and (for mail) 7008 Amherst, University City, Mo. CARLSON, C. O. (A 1937) Owner (for mail) C. O. Carlson Htg. Co., 1627 Washington Ave., N., and 1806 Thomas Ave., N., Minneapolis, Minn. CARLSON, Conrad V. (/ 1937) Engr., c/o . Phillips Petroleum Co., Engrg Dept., Bartles ville, Okla. . CARLSON, Everett E. (At 1932; A 1929) Br. Mgr. (for mail) The Powers Regulator Co., 1010 Louderman Bldg., and 6652 Washington Ave., St. Louis, Mo. CARNAHAN, John H. (A 1940; J 1937) Design . Engrg. Dept., Oklahoma Gas and Electric Co., 321 N. Harvey St., and (for mail) 3116 N. W. 26th St., Oklahoma City, Okla. CARNEY, Edward J. (A 1939) Htg. Contractor- Partner (for mail) John C. Kohler Co., 554 N. 16th St., and 1020 N. 64th St., Philadelphia, Pa. CARON, Hector (A 1038) Mgr.-Owner (for mail) Heating & Air Conditioning, 421 S. 3rd St., Rodielie, III.* CARPENTER, Raymond D. (S 1938) California Polytechnic, San Luis Obispo, and (for mail) 534 Bay St., Santa Cruz, Cam. CARPENTER, R. H. (At 1921) (Council, 1930 1935) Mgr., New York Office (for mail) Nash Engineering Co., Graybar Bldg., 420 Lexington Ave., New York, and 20 Jefferson Ave., White Plains, N. Y.. * CARR, Maurice L.* (Af 1931) Director, Pitts burgh Testing Laboratory, Stevenson & Locust Sts., Pittsburgh, Pa. CARRIER, Earl G. (Af 1936; / 1929) Br. Mgr., Carrier Corp., P. O. 188, New Haven, and (for mail) Northford, Conn. CARRIER, Willis H.* (Af 1913) (Presidential Member) (Pres., 1931; 1st Vice-Pres., 1930; 2nd . Vice-Pres., 1929; Council, 1923-1932) Chairman of the Board (for mail) Carrier Corp., 302 S. Geddes St., and 2570 valley Drive, Syracuse, N. Y. . CARROLL, Arthur F. (Af 1938) Development Engr., Automatic Products Co., 2450 N. 32nd St., and (for mail)'5525 Brooklyn PI., Milwaukee Wis. - CARROLL, Edgar E. (A 1939) Owner (for mail) Kleenair Furnace Co., 5329 N. E. Sandy Blvd., and 2434 N. E; 43rd Ave., Portland, Ore. CARROLL, William M. (/ 1938) Sales Engr. (for mail) Tom Dolan Heating Co., 614 W. " Grand, and 908 East Drive, Oklahoma City> Okla. CARTER, Alexander W. (A 1940; J 1936) Htg. Engr. (for mail) Monarch Brass Mfg. Co., Ltd., 71 Browns Ave., and 117 Elmer Ave.,'Toronto. Ont., Canada. . CARTER, Doctor (Af 1934) Consulting Engr.,-32 New House Park, St. Albans, Herts., England. 17 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CARTER, John H.* (Af 1936) Mgr. Refrig. Dept, (for mail) Kupferle-Hicks Heating Co., 3974 Delmar Blvd., St. Louis, and 341 Spring Ave., Webster Groves. Mo. CARY. Edward B. (Af 1935) Partner (for mail) John Paul Jones, Cary & Millar, Cons. Engrs., 448 Terminal Tower, Cleveland, and Chillicothe Rd., Aurora, O. CASE, Delbert V. (Af 1937) Owner, Case Engi neering Co., 428 Dwight Bldg., Kansas City, and (for mail) Rte. 1, Hickman Mills, Mo. CASE, Walter G. (A 1930) Mgr., Ideal Boilers & . Radiators, Ltd., Ideal House. Great Marl borough St., London, W. 1, and (for mail) 66 The Ridgeway, Kenton. Harrow, Middlesex, England. CASEY, Byron L. (Af 1921) Sales Engr. (for mail) Ilg Electric Ventilating Co., 222 N. LaSalle St., Chicago, and 307 Vine Ave., Park Ridge, III. CASKEY, Luther H., Jr. (5 1938) Student (for mail) Carnegie Institute of Technology, Box 310, Pittsburgh, Pa., and 513 N. Queen St., Martins- burg, W. Va. CASPERD, Henry W. H. (A 1938; 7 1930) Engr.. Carrier Co.. Ltd., 24 Buckingham Gate, London, and (for mail) 21 Robin Hood Lane, Sutton, Surrey, England. CASSELL, Grant E. R. (A 1939) Maintenance Mech. (for mail) Cliadoz Realty Co., Inc., 9 E. 96th St., and 1250 Park Ave., New York, N. Y. CASSELL, John D.* {Life Member; M 1913) (Council, 1930-1935) Retired, 2008 Walnut St., Philadelphia, Pa. . CASSELL,William L. (M 1936) Owner (for mail) William L. Cassell, Cons. Engr., 2501 Telephone Bldg., Kansas City, and R. F. D. No. 6, Inde pendence, Mo. CAWBY, Elmer L. (A 1938; 7 1935) Sales Engr. (for mail) Carrier-Bock Corp., 804 Neil P. ' Anderson Bldg., Ft. Worth, Tex. CHALMERS. Charles H. (Af 1925) Gen. Mgr. (for mail) Chalmers Oil Burner Co., 1234 Central Ave., and 523-7th St., S. E., Minneapolis, Minn. CHAMBERS. Fred W. (Af 1936) Pres, (for mail) F. W. Chambers & Co., Ltd., 96 Bloor St., West and 122 Garfield Ave., Toronto, Ont., Canada. CHAMPLIN, Robert C. (A 1938) Assistant to Air Cond. Engr. (for mail) Timken Silent Auto matic Div., 100-400 Clark Ave., and 13640 Mendota Ave., Detroit, Mich. CHAPIN, C. Graham (Af 1933) Treas. (for mail) Hopson & Chapin Mfg. Co., 231 State St., and 66 Faire Harbour Place, New London, Conn. CHAPIN, Harvey G. (Af 1935) Sales Engr. (for mail) Westerlin & Campbell Co., 1113-15 Cornelia Ave., and 8151 Ingleside Ave., Chicago, 111. CHAPMAN, William A., Jr. (Af 1936) Sales Planning Div. (for mail) Frigidaire Div., General . Motors Sales Corp., 300 Taylor St., and 525 Daytona Parkway, Dayton, O. CHARLES, Paul L. (Af 1938) Mgr. (for mail) Walsh & Charles, 406 Tribune Bldg., and 145 Ash St., Winnipeg, Man., Canada. CHARLET, Louis W. (Af 1934) Branch Mgr. (for mail) Kewanee Boiler Corp., 37 W. 39th St., New York, and 427 Rich Ave., Mt. Vernon, N. Y. CHASE, Arthur M,, Jr. (Af 1938) Sales Engr. (for mail) York Ice Machinery Corp., P. O. Box 359, and 3333 Ozark St.. Houston, Tex. CHASE, Chauncey L. (Af 1931) Partner (for mail) Edward E. Ashley, Cons. Engr., 10 East 40th St., New York, and 8829 Fort Hamiltpn Pkwy., Brooklyn, N. Y. CHASE. L. Richard (Af 1938; J 1931) Mgr., Air Cond. Dept, (for mail) The Carter-Waters Corp., 2440 Pennway, and 4915 Bell, Kansas City. Mo. CHASE, Roger E. (A 1939) Prea. (for mail) R. E. Chase & Co.. Inc., Tacoma Bldg., Tacoma, and Wollochet Bay (via Gig Harbor), Wash. CHEATWOOD. William H. (A 1939; 7 1937) Commercial Engr. (for mail) Air-Rite Corp., 3123 Holmes St., and 1815 Grand Ave., Dallas, Tex. CHEESEMAN. Evans W. (7 1937; S 1934) Engr., Perfection Stove Co., 7609 Platt Ave., and (for mail) 2200 Prospect Ave., Clevelandj O. CHEN, Sarcey T. (Af 1936) Executive Vice-Pres. (for mail) American Engineering Corp., 989 Bubbling Well Rd., and 45/24 Great Western Rd., Shanghai. China. CHENEVERT, J. Georges (Af 1938) Consulting Engr. (for mail) Arthur Surveyer & Co., Room 1203-1010 St. Catherine St., W., and 536 Outremont Ave.. Montreal, P. Q., Canada. CHENOWETH, Dale M. (7 1938; S 1936) Asst. Supt. of So. Braintree Factory, Armstrong Cork Co., and (for mail) 1000 Washington St., South Braintree. Mass. CHERNE, Realto E. (Af 1938; 7 1929) Dist. Chief Engr.. Carrier Corp., and (for mail) 606 Char- mouth Drive, Syracuse, N. Y. CHERRY, Lester A.* (Af 1921) Consulting Engr. (for mail) Industrial Planning Corp., 271 Dela ware Ave., and 151 Euclid Ave., Buffalo, N. Y. CHESTER, Thomas* (Af 1917) Consulting Engr., c/o Davidson & Co., Ltd., Central House, Kingsway, London, England. CHEYNEY, Charles C. (A 1913) Asst. Sales Mgr. (for mail) Buffalo Forge Co., 490 Broadway, and 255 Lincoln Parkway. Buffalo. N. Y. CHILDS, Lewis A. (Af 1938) Dist. Sales Mgr. (for mail) Clarage Fan Co., 520 Commercial Trust Bldg., and 1320 Foulkrod St., Philadelphia, Pa. CHRISTENSON, Harry (A 1931) Partner (for mail) Hunter-Prell Co., 38 S. Madison St., and 121 Sunset Blvd., Battle Creek, Mich. CHRISTMAN, William F. (A 1932; 7 1931) Engr. , (for mail) Kroeschell Engineering Co., 215 W. Ontario St., and 5649 Artesian Ave., Chicago, 111 CHRISTOPHERSON, Andrew E. (Af 1935) Engr.-Custodian (for mail) Board of Education, Spalding School, 1628 Washington Blvd., and 2923 N. Kilpatrick Ave., Chicago, III. ' CHRONE, Robert E. (Af 1938) Chief Engr., R. F. Taylor, Cons. Engr., 909 Bankers Mortgage Bldg., Houston, Tex. CHURCH, H. J. (Af 1922) Mgr, (for mail) Darling Brothers, Ltd., 137 Wellington St., W,, Rm. 904, Toronto, and 358 Main St., N., Weston, Ont., Canada. CITRON, Daniel J. (S 1938) 2055 Ryer Ave.. New York, N. Y. CLAR, Robert. Jr. (A 1938) Sales Engr. (for mail) United States Radiator Corp., 127 Campbell Ave., and Lee Crest Apartments, 2nd Blvd. at Blaine, Detroit, Mich. CLARE, Fulton W. (Af 1927) 935 Plymouth Rd.. N. E., Atlanta, Ga.. . CLARK, Adrian N. (A 1939) Engr., Good House . keeping Inst.. 8th Ave. & 57th St., New York, and (for mail) 86 Chase Rd., Manhasset, L. I., N. Y. CLARK, Albert C. (A 1939) Engr., Century Co.. 223 S. W. 6th Ave., and (for mail) 3742 N. E. 68th Ave., Portland, Ore. CLARK, E. Harold (Af 1922) Manufacturer's Agent, 600 Michigan Theatre Bldg., and (for mail) 2539 Lakewood, Detroit, Mich. CLARK, Lynn W. (A 1938) Engr. and Salesman (for mail) Hall-Neat Furnace Co., 1324 N. Capitol Ave., and 737 West 32nd St., Indianapolis, Ind. CLARK, Robert L. (A 1918) Pres., The Clark Asbestos Co.. 1893 E. 55th St., Cleveland, and for mail) 927 Caledonia Ave., Cleveland Heights, CLARKSON, John R. (5 1938) David Ranken Jr. School of Mech. Trade, Air Cond. Dept., 4431 Tinney Ave., and (for mail) 4620-A'New berry Terrace, St. Louis, Mo. CLAUSEN, Arnold H. (Af 1939) Air Cond. Engr. (for mail) 404 E. Howell, Seattle, Wash., and 2820 Scott St., San Francisco, Calif. CLAY, Wharton (Af 1939; A 1938) Secy, (for mail) National Mineral Wool Assn., 1270 Sixth Ave., New York, and 127 S. Broadway, Nyack, N. Y. CLEGG, Carl (Af 1922) Dist. Mgr. (for mail) - American Blower Corp., 311 Mutual Bldg., and 3513 Gillham Rd., Kansas City, Mo. 18 ROLL OF MEMBERSHIP CLEVELAND, Clyde C. (A 1936) Htg. Engr.. Johnson & Cleveland, 192 Main St., and (for mail) 64 E. Main St.. Bradford. Pa. CLIFTON, John A. (A 1938) Salesman, Warden King, Ltd., 299 Adelaide St., W., and (for mail) 369 Belsire Drive, Toronto, Ont., Canada. CLINE, Edward A. (Af 1937) Consultant on Air and Water Conditioning, Rcyam -512 Architects Bldg., 816 West 5th, Los Angeles, Calif. CLO, Harry E. (7 1939) Sales Engr. (for mail) Air Filter & Equipment Corp., 228 N. LaSalle St., Rm. 1310 Chicago, and 630 Library PL, Evanston, 111. CLOSE. Paul D.* (Af 1928) Tech. Secy, (for mail) Insulation Board Tnst., Ill W. Washington St., Chicago, and 757 Maclean Ave., Kenilworth, III. CLOSE, Robert (Af 1938) Chief Air Cond. Engr., National Broadcasting Co.. 30 Rockefeller Plaza, New York. N. Y.. and (for mail) 199 Ames Ave., Leonia. N. J. CLOSNER, J. J. (7 1938) Sales Engr. (for mail) Robischung-Kiesling, Inc., 4848 Main St., and 4435 Jefferson. Houston, Tex. ' COCHRAN, Charles C. (A 1935) Asst. Sales Mgr., Chicago Office. Minneapolis-Honeywell Regulator Co., 433 East Erie, Chicago, and (for mail) 840 S. Clifton Ave., Park Ridge, III. COCHRAN, Lex H. (Af 1934) Sales Mgr.. Western Div. (for mail) American Blower Corp., 625 Market St., and 130 Camino Del Mar, San Francisco, Calif. COCKINS, William W. (7 1937) Sales Engr. (for mail) The Trane Co., 1129 Folsom *St., San Francisco, and 576 The Alameda. Berkeley, Calif. CODY, Henry C. (Af 1936) Sales Engr.. Pierce Butler Radiator Corp., 19th & Glenwood Ave., and (for mail) 7336 North 21st St., Philadelphia, Pa. COGHLAN, Sherman F. (A 1937) Metropolitan Water Dist. of Southern Calif., 306 W. Third St., Los Angeles, and (for mail) 414 Ninth St.. Santa Monica, Calif. COHAGEN, Chandler C. (Af 1919) Archt., 211 ' Hedden Bldg, (for mail) Box 2100, and 235 Avenue G. Billings, Mont. COHEN, Philip (Af 1932) Dist. Mgr. (for mail) B. F. Sturtevant Co., 401 E.'Qhio Gas Bldg., and 7100 Euclid Ave., Suite No. 6, Cleveland, O. COLBY, John H. (7 1939) Sales Engr. (for mail) Johnson Service Co., 20 Winchester St., Boston, and 25 Jefferson Rd., Wellesley Hills. Mass. COLCLOUGH, Otho T. (A 1933) Custodian, American Legation, and (for mail) 726 Parkdale Ave., Ottawa. Ont., Canada. COLE, C. Boynton (A 1940; 7 1937) Chief Engr., Air Cond. Dept., The Murray Co., Howell Mill Rd., P. O. Box 1517, and (for mail) 1843 Flagler Ave., N. E.t Atlanta, Ga. COLE, Grant E. (A 1925) Vice-Pres. & Gen. Mgr., Trane Co. of Canada, Ltd., 4 Mowat Ave., Toronto, Ont., Canada. COLEMAN. John B. (Af 1920) Chief Engr. (for mail) Grinnell Co., Inc., 260 West Exchange St., and 237 Cole Ave., Providence, R. I. COLFORD, John (A 1937) Pres., John Colford. Ltd.. 2007 Guy St., Montreal, and (for mail) 51 Upper Bellevue Ave., Westmount, P. Q., Canada. COLLE. Samuel S. (A 1938) Engr. & Owner (for mail) Air Conditioning Engineering Co., 361 You- ville Square, and 1489 Atwater Ave., Montreal, P. Q.. Canada. COLLIER, William I. (Af 1921) Pres, (for mail) W. 1. Collier & Co., 522 Park Ave., Baltimore, and Ellicott St., Ellicott City. Md. COLLINS, John F. S., Jr. (Af 1933) Secy.-Treas. (for mail) National District Heating Assn., 1231 Grant Bldg., and 827 N. Euclid Ave., Pitts burgh. Pa. COLMENARES, Caspar Vizoso (A 1938) VicePres. & Gen. Mgr. (for mail) Castel-Vizo, Refrigeracion y Aire Acondicionado S. A., Obrapia 407, P. O. Box 210, and 19th St., No. 1001, Vedado. Havana, Cuba. COMB, Fred R., Jr. (7 1938; 5 1937) Sales Engr., Delco-Frigidaire Conditioning Div., 2446 Uni versity Ave., St. Paul, and (for mail) 2425 Bryant Ave., S., Minneapolis, Minn. COMO, Jack A. (Af 1939) Engr. (for mail) Buck- head Plbg. & Htg. Co., 3051 Peachtree Rd., and 2865 Elliot Circle, N. E., Atlanta, Ga- COMSTOCK, Glen M. (A 1926) Sales Repr. Engrg. (for mail) L. J. Wing Mfg. Co., 604 Chamber of Commerce Bldg., Pittsburgh, and 154 College Ave., Beaver, Pa. CONATY, Bernard M. (Af 1935) Sales Mgr. (for mail) American District Steam Co., North Tonawanda, and 1306 Delaware Ave.. Buffalo, N. Y. CONE, William E. (7 1937) Air Cond. Engr. (for mail) Shook & Fletcher Supply Co., 1814 1st Ave.. N., and 1037 10th Ave., S., Birmingham, Ala. CONNELL, Harold (Af 1935) Engr.. Armo Cooling & Ventilating Co., 30 West 15th St., New York, N. Y., and (for mail) 446 Bogert Ave., Ridge wood, N. J. CONNELL, Richard F. (Af 1916) Mgr., Capitol Testing Laboratory (for mail) U. S- Radiator Corp., 1056 National Bank Bldg., and 2970 Burlingame, Detroit, Mich. CONNER. Raymond M. (Af 1931) D>r. Testing Laboratories (for mail) American Gas Asso ciation. 1032 East 62nd St.. Cleveland, and 271 East 216th St., Euclid, O. CONRAD, Roy (Af 1935) Sales Engr., Carrier Corp., 1500 S. Santa Fe, Los Angeles. Calif., and (for mail) 3416 Colfax '`B", Denver, Colo. CONSTANT, Earl S. (7 1935) Air Cond. Sales Engr., P. H. Hensarling Co., 713 Bankers Mortgage Bldg., and (for mail) 2802 Bagby St.. Houston, Tex. COOK, Arthur L. (A 1938) Engr., Power Plant, A. & M. College of Texas, and (for mail) P. O. Box 248, College Station, Tex. COOK, Benjamin F. (Af 1920) Consulting Engr.. 114 W- Tenth St. Bldg., Kansas City, and (for mail) 1720 Overton Ave., Independence, Mo. COOK, George E. (A 1937) Pres, (for mail) Air Conditioning, Inc., 2324 Hampden Ave'., St. Paul, and 2115 Blaisdell Ave., Minneapolis, Minn. COOK, H. Dale (A 1938) Sales Engr. (for mail) General Controls Co., Ino, 450 E. Ohio St.. Chicago, 111., and 73 East 10th St., Holland, Mich. . COOK, Ralph P. (Af 1930) Asst. Supt., Engrg. & Maintenance Dept, in charge of Engrg. Div. (for mail) Eastman Kodak Co., Kodak Park, and 663 Seneca Parkway, Rochester, N. Y. COOKE. Thomas C. (A 1937) Htg. & Air Cond. Engr. (for mail) Tomlinson Co., Inc., 400-402 E. Peabody St., P. O. Box 217, and 1118H Eighth St.. Durham, N. C. COOLEY, Edgerton C. (Af 1937) Mfrs. Agent (for mail) E. C. Cooley Co., 625 Market St., San Francisco, and Los Altos, Calif. COOMBE, James (A 1932) Vice-Pres. (for mail) William Powell Co., 2525 Spring Grove Ave.', and 2363 Grandin Rd., Cincinnati, O. COON, Thurlow E. (Af 1916) Pres, (for mail) The Coon-DeVisser Co., 2051 W. Lafayette, and 826 Edison Ave., Detroit, Mich. COOPER, Dale S. (Af 1938; A 1937) Consulting Engr. (for mail) 2615 Fannin St., and 2027 Sunset Blvd., Houston, Tex. . COOPER, Donald E. (7 1939) Partner (for mail) D. E. Cooper & Son. 540 Hood St., and 1440 N. Liberty. Salem, Ore. COOPER, John W. (Af 1932; A 1925; 7 1921) . Repr. (for mail) Buffalo Forge Co.. 1598 Arcade Bldg., St. Louis, and 612 Hawbrook Drive. Kirkwood. Mo. COOPER, William B. (7 1937) Application Engr., Home Htg. Dept., Air Cond. Div. (for mail) Westinghouse Electric & Mfg. Co., Springfield, and N. Main St., N. Wilbraham, Mass. COPPERUD, Edmund R. (7 1933) Asst. -Mgr., Minneapolis Plumbing Co., 1420 Nicollet Ave.; and (for mail) 17 West 25th St., Minneapolis, Minn. 19 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 COREY, George R. (M 1936) Engr., 40 Sias Lane. Milton. Mass. /. CORNWALL, Charles C. (/ 1935) Research Engr., The Bahnson Co,. 1001 S. Marshall St., and (for mail) 473 Carolina Circle, Winston- Salem. N. C. _. _ CORNWALL, George I. (Af 1919) Sales Engr., Burnham Boiler Corp., Elizabeth, N. J. CORRAO, Joseph (A 1936; J 1933) Engr., City of San Francisco. Dept, of Works. Engrg. Dept.. City Hall, and (for mail) 854 31st Ave.. San Francisco, Calif. ,, ^___ CORRIGAN. James A. (A 1940; J 1935 5 1930) Engr. (for mail) Corrigan Co., 2501 St. Louis Ave., and 6130 McPherson Ave., St. Louis, Mo. COST, George W. (J 1939; S 1938) Cornelius Engineering Corp.. 628 Rebecca Ave.. Wilkins- burg, and (for mail) 5556 Forbes St., Pittsburgh, Pa. COTT, William B. (Af 1940) Air Cond. Engr.. The Doermann-Roehrer Co., 450 E. Pearl St., and (for mail) 3001 Bellewood Ave., Cincinnati, O. COVER, E. B. (Af 1937) Sales Engr., York Ice Machinery Corp., 115 S. 11th St., St. Louis, Mo., and (for mail) 3252 Waverly, East St. Louis, 111. COVER, Richard R. (A 1936) Engr., Carrier Corp., 12 S. 12th St., Philadelphia, Pa., and (for mail) 1302 Gallatin St., N. W., Washington, D. C. COWARD, Charles W. (Af 1935) Pres, (for mail) Coward Engineering Co., 411 Cooper St., Cam den, and 815 Lincoln Ave., Palmyra, N. J. COWELL, Robert J. (Af 1922) Hotel Miramar, Prado 2, Esq. A. Malecon, Havana, Cuba. COX, Harrison F. (A 1930) Htg. & Air Cond.. 243 Carroll St., Paterson, N. J. COX, Philip E. (M 1938) Engr., Societe des Cine-Theatres d'lndochine, and (for mail) 50 Boulevard Dongkhank, Hanoi, Tonkin, French Indo China. COX, Samuel F. (Af 1939) Dir. Tech. Sales (for mail) Pittsburgh-Coming Corp., 4337-5th Ave., and 6049 Bunker Hill St., Pittsburgh, Pa. COX, Thomas M., Jr. (J 1937) Sales Engr., . Refrigeration and Air Cond. (for mail) Carrier Corp., International Div., Syracuse, and 9320 224th St., Queens Village, L. I., N. Y. COX, Vernon G. (A 1939) Dist. Sales Mgr., Century Electric Co. (for mail) 514 Mercantile Bldg., 810 Main St., and 207 Yarmouth St., Dallas, Tex. COX, William W. {Life Member; M 1923) Pres, and Mgr. (for mail) Heating Service Co., Inc., 326 Columbia St., and 6232 31st Ave., N. E., Seattle, Wash. CRANE, Robert S. {M1938) Dist. Engr. (for mail) Frigidaire Div., General Motors Sales Corp., 4 Cummins Station, and 3514 Harding Rd., Nashville, Tenn. CRAWFORD, Arthur C. (A 1938) Sales Engr., Potomac Electric Power Co., 10th & E St., N. W.. and (for mail) 429 Butternut St., N. W., Washington, D. C. CRAWFORD, John H,, Jr. (A 1936; J 1930) Air Cond. Engr.. Hitchen Co., 441 Lexington Ave., New York, N. Y., and (for mail) 289 Reynolds Terr.. Orange. N. J. CRIBARI, Hugo E. (A 1937) Salesman, American Radiator & Standard Sanitary Corp., 40 West 40th St., New York, and (for mail) 468 N. Fulton Ave., Mt. Vernon, N. Y. CRIQUI, A. A.* (M 1919) Chief Engr., Htg. & Vtg. Dept.. Buffalo Forge Co., 490 Broadway, Buffalo, and (for mail) 39 St. Johns Ave., Kenraore, N. Y. CROMBIE, James (A 1939) Sales Engr., American Radiator & Standard Sanitary Corp*. Elyria, and (for mail) 3901 Oak St., Mariemont, Cincinnati, O. CRONE, Charles E. {M 1922) Pres, (for mail) Charles E. Crone Co., 1656 N. Ogden Ave., and 1320 N. State St., Chicago, 111. CRONE, Thomas E. (Life Member', M 1920) c/o Mrs. Carol Brown, Apt. 6-B, 3705-80th St., Jackson Heights, L. I., N. Y. CRONEY, P. Alfred (M 1938) Chief of Mech. Section, U. S. Housing Authority, Interior Bldg.; N., Washington, D. C., and (for mail) 21 Phila delphia Ave., Takoma Park, Md. CROPPER, Robert O. {M 1938) Head Operating Engr. of Refrigeration Plant & Htg. Equip., War Dept., c/o Quartermaster. Fort Knox, and (for mail) Vine Grove, Ky. CROSBY, Edward L. {M 1936) Pres, (for mail) Henry Adam9, Inc., Cons. Engrs., 1015-1023 Calvert Bldg., and 5323 Belleville Ave., Balti more, Md. CROSS, Freeman G. {M 1936) Sales Mgr., Controls Div. (for mail) Fulton Sylphon Co., and 31 Nokomis Circle, Knoxville, Tenn. . CROSS, Robert C.* (M 1937) Fuel Engr. (for mail) Battelle Memorial Institute, 505 King Ave., and 1178 Virginia Ave., Columbus, O. CROSS, Robert E. (M 1938; A 1931) Dist. Mgr. (for mail) Minneapolia-Honeywell Regulator Co., 271 Columbus Ave., and 68 Kimberly Ave., Springfield, Mass. CROUT, Marvin M. (M 1939; A 1938) Branch . Mgr. (for mail) York Ice Machinery Corp., 412 Houston St., and 2392 Hurst Drive, Atlanta, Ga. CRUMP, Alvin L. {M 1937) Sales Engr. (for mail) Powers Regulator Co., 2720 Greenview Ave., Chicago, and 2701 Payne St., Evanston, 111. CUCCI, Victor J. (M 1930) Consulting Engr. (for mail) 347 Madison Ave., New York, and 451 55th St., Brooklyn, N. Y. CULBERT. William P. (A 1929) Partner (for mail) Culbert-Whitby Co., 2019 Rittenhouse St., Philadelphia, and 929 Alexander Ave., Drexel Hill, Pa. CULLEN, Augustine G. {M 1939; A 1936) Pres, (for mail) Cullen, Inc., 20 L St., S. W., Washing ton, D. C.. and 6826-19 Rd., North Falk Church, Va. - CULLIN, William W. {M 1938) Chief Engr.. Home Insulation Div., Johns-Manville Sales Corp., 22 East 40th St., and (for mail) 2995 Botanical Sq., New York, N. Y. CUMMING, Ford J. {M 1936) Pres, (for mail) Beecher-Cumming, Inc., 820 2nd Ave.. S.. Minne- . apolis, and 120 Interlachen Rd., Hopkins, Minn. CUMMING, Robert W. (M 1928) Engr. & Sales Executive, Sarco Co., Inc., 183 Madison Ave.. New York, and (for mail) 81 Alkamount Ave., Scarsdale, N. Y. CUMMINGS, Carl H. (A 1927; J 1926) Mgr. (for mail) Industrial Appliance Co. of New England, 110 Arlington St., Boston, and 41 Edgehill Rd., Chestnut Hill, Mass. CUMMINGS. C. J. (M 1923) Vice-Pres. (for mail) The Scott Co.. 113-lOth St., and 851 Trestle Glen Rd.. Oakland, Calif. CUMMINS. George H. (Af 1919) Dist. Mgr.. . Aerofin Corp., 918 United Artists Bldg., and (for mail) 16210 Ashton Rd., Detroit, Mich. CUMNOCK, H. (A 1938) (for mail) Little Rock Refrigeration Co., 417 W. Capitol Ave., and 609 Rock, Little Rock, Ark. . CUNNINGHAM, John S. (J 1937: 5 1935) Engr., Dowagiac Steel Furnace Co., and (for mail) 311 N. Front St., Dowagiac, Mich. CUNNINGHAM, Thomas M. {M 1931; J 1930) Production Mgr., Carrier Corp., 7-122 Mer chandise Mart. Chicago, III. CURRIER, Charles H. (M 1919) (for mail) Ross Heater & Mfg. Co., Inc., 1407 West Ave., and Park Lane Apts., 33 Gates Circle, Buffalo, N. Y. CURRY, Roger F. {J 1940; S 1938) Jr. Engr.. Sales Engrg. Dept., The Laclede Gas Light Co.. 1017 Olive St.. St. Louis, and (for mail) 3142 Sutton Btvd., Maplewood, Mo. CURTICE, Jean M. (A 1936) Htg. Engr. and Dist. Mgr., Citizens Utilities Co., 15 W. Fourth St., La Junta, Colo. CURTIS, Herbert F. (A 1934) Chief Engr. (for mail) Henry Furnace & Foundry Co., 3471 East 49th St., Cleveland, and 59 Fourth Ave., Berea. O. 20 ROLL OF MEMBERSHIP CUSHING, Charles F. (Af 1938) Mgr. Air Cond. Sales. Bryant Heater Co., 17825 St. Clair Ave., Cleveland, O. CUTLER, Joseph A. (Af 1916) (Council. 1920 1926) Pres, and Gen. Mgr. (for mail) Johnson Service Co., 507 East Michigan St., and 4811 N. Lake Drive, Milwaukee, Wis. D DADDARIO, Frank T. (J 1939) Air Cond. Engr., The Lancaster Co., Johnson City, Tenn., and (for mail) 1112-15th Ave., Hipkory, N. C. DAFTER, Edwin H. (Af 1938) Sales Engr. (for mail) Carrier Corp., 12 S. 12th St., and 236 Henley Rd., Penn Wynne, Philadelphia, Pa. DAHLSTROM, Godfrey A, (A 1927) Htg. Sales Engr., American Radiator & Standard Sanitary Corp., 312 S. Third St., and (for mail) 3721-47th Ave., S., Minneapolis, Minn. DAITSH, Abe (J 1937) Air Cond. & Refrig. Engr. (for mail) Henderson-Smart (Pty.) Ltd., 143-145 Annan House, and 706 Mansfield House, Johan nesburg, South Africa. DALY, Robert E. (Af 1931) Engr. (for mail) . American Radiator & Standard Sanitary Corp.. 40 W. 40th St., New York, and 270 Bronxville Rd., Bronxville, N. Y. D'AMBLY, A. Ernest (Af 1924; J 1921) (for mail) 901 Architects Bldg., Philadelphia, and 242 E. Montgomery Ave., Ardmore, Pa. DANIEL, William E. (J 1939) Partner (for mail) E. Ashby & Co., Jamaica Wharf, 20 Upper Ground, Blackfriars. and 9 Dudley House, Westmoreland St., London, W. 1, England. DANIELSON, E. B. (A 1936) Owner-Mgr. (for mail) Electric Service Co., 132 West St., and 819 Main St., Russell, Kan. DANIELSON, Ellsworth H. (A 1940; J 1938) Dist. Mgr., Minneapolis-Honeywell Regulator Co., 2831 Center SL, Des Moines, la. DANIELSON, Lloyd C. {J 1938; 5 1936) Sales Mgr., Home Service Co., 821 Main St., Russell, Kan. DANIELSON, Wilmot A.* (Af 1935) Co!.. U.S.A. Quartermaster and Constructing Quartermaster, Quarry Heights. Canal Zone, Panama. DARBY, Marion H. (A 1938; J 1930) Chief Engr., Air Cond. Dept., Servix Electrica Ltda., Rua Senador Pompeu 46/58, and (for mail) Rua Redemptor 178, Rio de Janeiro. Brazil, South America. DARLING. Arthur B. (A 1929) Asst. Sales Mgr. (for mail) Darling Bros., Ltd., 140 Prince St., Montreal, and 4326 Sherbrooke St., W., Westmount, P. Q., Canada. DARLINGTON, Allan P. (Af 1930) Sales Engr. Power Apparatus (for mail) American Blower Corp., 6000 Russell St., and 5200 Haverhill Detroit, Mich. DARTS, John A. (Af 1919) Kewanee Boiler Co., Inc., 101 Park Ave., New York, N. Y. DASING, Emil (Af 1937) Designing Engr., Sears Roebuck & Co., 925 S. Homan Ave., and (for mail) 4729 N. Talman Ave., Chicago, ill. DAUBER, Oscar W. (Af 1937) Consulting Engr. (for mail) 224 S. Michigan Ave., Chicago, and 366 Winnetka Ave., Winnetka, 111. DAUBERT. LeRoy L. {J 1937) Engr., Tone Air Conditioning Co., 561-7th St., and (for mail) 4311 Sheridan, Des Moines. la. DAUCH, Emil O. (Af 1921) Secy.-Treas. (for mail) McCormick Plumbing Supply Co.. 1675 Bagley Ave., Detroit, and 729 Bedford Rd., Grosse Pointe Park, Mich. DAVEY, Geoffrey I. (Af 1937) Consulting Engr., Haskins, Davcy & A. G. Gutteridge, 60 Hunter St., Sydney, N. S. W., Australia. DAVIDSON, John C. (A 1940; J 1936) Air Cond. Inspector, City of Minneapolis (for mail) 213 City Hall, and 4708 Isabel Ave.. Minneapolis. Minn. DAVIDSON, L. Clifford (Af 1927) Associate Dist. Mgr. (for mail) Buffalo Forge Co., 220 S. 16th St., Philadelphia, and 322 Winding Way, Merion, Pa. DAVIDSON. Philip L. (Af 1924; J 1921) Con sulting Engr. (for mail) 1600 Walnut St., Phila delphia, and Radnor, Pa. . DAVIES, George W. (Af 1918) Mgr. (for mail) G. W. Davies & Co., 19 Maclaggan St., Dunedin. C. 1, P. O. Box 390, Dunedin. N. 2, and Colins- wood, Macandrew Bay, New Zealand. DAVIES, Reginald H. (Af 1939) Gas Htg. Adviser. The Colonial Gas Assn., Ltd., Collins House', 360 Collins St., Melbourne, and (for mail) "Harelands," Wiilsmere Rd., Kew, Victoria, Australia. DAVIS, Arthur C.* (Af 1920) 73 Preston St.. Ridgefield Park, N. J. DAVIS, Arthur F. (Af 1934) Pres, (for mail) Johnson & Davis Plumbing & Heating Co., 2235 Arapahoe St., and 1901 Ivanhoe St., Denver, Colo. DAVIS, Bert C. (Life Member; Af 1904) (Council. 1917) Pres, and Treas. (for mail) American Warming & Ventilating Co., 317 Pennsylvania Ave., and 603 W. Church St., Elmira, N.' Y. DAVIS. Calvin R. (Af 1927) Branch Mgr. (for mail) Johnson Service Co.. 2328 Locust St.,` and 7534 Westmoreland Drive, St. Louis, Mo. DAVIS, Charles (Af 1938) Engr. (for mail) Rathe- Heating Corp., 700 Elton Ave., and 281 Wads worth Ave., New York, N. Y. * DAVIS, Donald W,, Jr. (J 1939) Sales Engr., B. F. Sturtevant Co., and (for mail) 307 Waverly Way, Greensboro, N. C. DAVIS, Edward J. {J 1938) Sales Engr. (for mail) Gurney Foundry Co., Ltd., 4 Junction Rd., Toronto, and Lakeview, OnL,'Canada. DAVIS, George C. (Af 1939; J 1936) Vice-Pres. (for mail) Northern Public Service Corp., Ltd., 307 Power Bldg., and 923 Somerset Ave., Winnipeg, Man., Canada. DAVIS, George L., Jr. (A 1938) Estimator (for mail) L. L. McConachie Co., 1003 Maryland Ave., and 1300 Waybum St,, Detroit. Mich. DAVIS. Joseph (Af 1927; A 1926) Owner, Heating & Refrigeration Contractor (for mail) 70 West Chippewa St., and 166 Huntington Ave., Buffalo. N. Y. DAVIS, Keith T; (Af 1937) In charge of Engrg. (for mail) L. J. Mueller Furnace Co., and 1500 E. Marion. Milwaukee, Wis. DAVIS, Otis E. (Af 1929;. A 1925) Sales Engr.. Hoffman Specialty Co., Waterbury, Conn., and (for mail) Box 98, 1402-3rd Ave., Scottsbluff, Nebr. DAVIS, Robert J. (Af 1939; A 1933) Production Engr., Sweden Freezer Mfg. Co., 84 Bell St., and (for mail) 5922-35th St.. S. W.; Seattle. Wash. DAVIS, Rowland G. (A 1921) Sales Repr., 887 Nela View Rd., Cleveland Heights, O. DAVISON, Robert L. (Af 1934) Director of Housing Research (for mail) John B. Pierce Foundation, 37 West 39th St., New York, and Meadow Glen Rd., Fort Salonga, L. I., N. Y. DAWSON, Eugene F. (Af 1934) Assoc. Prof, of Mech. Engrg. (for mail) University of Oklahoma, and 229 E. Frank St., Norman, Okla. DAWSON, Thomas L. (Af 1930) Pres, (for mail)- Thomas L.' Dawson Co., 2035 Washington St.. Kansas City. Mo., and Shawnee Mission Rd., Rosedale Station, Kansas City, Kan. DAY, Harold C. (A 1934) Mgr. (for mail) Ameri can Radiator & Standard Sanitary Corp., 1807 Elmwood Ave., Buffalo, and 223 Woodcrest Blvd., Kenraore, N. Y. . DAY. Irving M. (A .1936) Sales Engr. (for mail) 709 Mills Bldg., Washington, D. C., and 405 Cumberland Ave., Chevy Chase, Md. DAY, V. S.* (Af 1924) Director Dealer Engrg. (for mail) Carrier Corp., and 316 Highland Ave., Syracuse, N. Y. . DAYNES, Joseph H. (Af 1938) Application Engr. (for mail) Canadian General Electric Co., Ltd., 212-214 King St., W.. and 25, Elvina Gardens, Toronto, Ont., Canada. 21 heating ventilating AIR CONDITIONING GUIDE 1940 DEAN. Carl H. {M 1936) Air Cond. Engr. (Cor mail) Oklahoma Natural Gas Co., P. O. Box 871, and 109 E. 26th PI.. Tulsa. Okla. DEAN, Charles L. (Af 1932) Asst. Prof. Mech. Engrg., University of Wisconsin. 305 University Extension Bldg., and (for mail) 102 Grand Ave., Madison, Wis. _ DEAN, Frank J.. Jr. (7 1935; 5 1934) Pres.. Dean- Hagny Corp.. 14th & McGee St., and (for mail) 6028 Walnut St.. Kansas City. Mo. DEAN, Marshall H. (71938; 5 1936) Secy.-Treas.. Dean-Hagny Corp., 14th & McGee St., and (for mail) 1030 W. 55th St.. Kansas City. Mo. DeBERARD, Philip E. (A 1939) Pres- (for mail) Conditioned Air Systems, Inc.. 5544 N. Harlem Ave., Chicago, and 1220 Greenwood Ave., Wilmette. 111. . DEE, Leo H. (7 1937) Design Engr., Standard Air Conditioning, Inc., Beechwood Ave._ & 2nd St., New Rochelle, and (for mail) 94 S. Highland Ave., Ossining, N. Y. , DEGLER, Howard E. (Af 1938) Prof, of Mech. Engrg. (for mail) University of Texas, and 1405 Hardovin Ave., Austin, Tex. DeLAND, Charles W. (Af 1924 r 7 1923) Secy.- Treas. (for mail) C. W. Johnson, Inc., 211 N. Desplaines St., and 2021 Estes Ave., Chicago, 111. DELANY, John V. (S 1938) Worcester Poly technic Institute, and (for mail) 34 Fruit St.`, Worcester, Mass. DELAVAN, Nelson B. (Af 1938) Senior Partner (for mail) Delavan Engineering Co., 414 12th St., and 338 42nd St., Des Moines, la. DELL'ORTO, Luciano (A 1940; 7 1938) Engr.. Refrig. Branch, Ing. Giuseppe Dell'Orto, 18 Via Merano, Milano (139) Italy. DEMAREST, Richard T. (7 1938) Sales Promo tion, Fitzgibbons Boiler Co., Inc., 101 Park Ave., and (for mail) 18 Jacobus PI., New York, N. Y. DEMETER, Julius (A 1939) Htg. & Air Cmid. Engr. (for mail) Julio Donoso D., Calle Lirios 375; Santiago, Chile. DEMING, Roy E. (A 1939) Htg. Engr. (for mail) Premier Furnace Co,, and 107 Jay St., Dowagiac, Mich. DEMPSEY, Stephen J. (A 1938) Pres.-Treas.. Stephen J. Dempsey Co. (for mail) 79 Harvard Battle Creek, Mich. DENHAM, Howard S. (Af 1939) 80 Dexter St.. Malden, Mass. DENISE, John R. (A 1937 ; 7 1935) Development Engr. (for mail) Surface Combustion Corp., 400 Dublin Ave., and 136 E. Broad St., Columbus, O. DENNY, Harold R. (A 1934) Eastern Mer chandise Mgr. (for mail) American Blower Corp., 50 W. 40th St., New York, N. Y., and 429 Edgewood Ave., Westfield, N. J. DEPPMANN, Ray L. (A 1937) Owner (for mail) R. L. Deppmann Co., 957 Holden Ave.,- and 13201 Cloverlawn Ave., Detroit, Mich. DE ROO, William C. (A 1939) Research & Development Engr. (for mail) Hart & Cooley Mfg. Co., and 126 W. 10th St., Holland, Mich, de SALES, Monteiro, Jr. (Af 1939) Chief Engr., Air Cond. Dept, (for mail) Isnard & Co., P. O. Box 3447, and Rua Senador Verjueiro 193, Rio de Janeiro, Brazil, South America. DE SOMMA, A. Edward (7 1937) Engr. (for mail) 2052 Homecrest Ave., Brooklyn, N. Y. DES REIS, John F. (Af 1936) Rua Duvivier No. 43, Edificio Itaoca, Apt. 46, Copacabana, Rio de Janeiro, Brazil, South America. DETERLING, William C. (A 1937) Salesman (for mail) General Electric Co., 570 Lexington Ave., New York, and 32 W. Milton St., Freeport, N. Y. DEVER, Henry F. (Af 1936; A 1935) Vice-Pres., Minneapolis-Honeywell Regulator Co., and (for mail) 4609 Edina Blvd., Minneapolis, Minn. DeVILBISS, Parker T. (A 1937) (for mail) Griffith-Dickinson Theatres, Inc., 3525 Broad way, Kansas City, Mo., and 708 E. Park PI., Oklahoma City, Okla. DEVORE, Angus B. (A 1937) Sales Engr. (for mail) James A. Messer Co., Inc., 1206 K St.. N. W., Washington, D. C., and 2016 Queens Chapel Rd. (Avondale) Hyattsville, Md. DEWEY, Ritchie P. (Af 1934) Mgr., Temperature Control & Uni-Flo Depts. (for mail) Barber- Colman Co., River & Loomis -Sts., and 2301 Oxford St.. Rockford, 111. DeWlLDE, Marinus Pieter (7 1938) Ing. M. P. DeWilde, M. T. S. H.. N. V. Ind. My. Gebr. Van Swaay, Banka Straat 134, and Riouw Straat 156, Den Haag (The Hague) Holland. DeWITT, Earl S. (A 1936) Branch Mgr., Wash ington Office (for mail) American Blower Corp., 438 Woodward Bldg.. Washington, D. C., and 3224 Oliver St., Chevy Chase, D. C. . DIAMOND, David D. (7 1937) Design Engr., Twin City Furance & Appliance Co., 13 S. 3rd St., Minneapolis, and (for mail) 118 E. Congress St., St. Paul, Minn. DIBBLE, S. E.* (Af 1917) (Presidential Member) ' (Pres., 1925; 1st Vice-Pres., 1924; 2nd Vice-Pres., 1932; Council. 1921-1926) Supt., Thomas Ranfcen Patton School, Elizabethtown, Pa. DICK, Andrew V. (7 1935) Partner, National Heating & Insulation Co., 91 N. Pearl St., and (for mail) 30 Delaware Ave., Albany, N. Y. DICKASON, Gray D. (Af 1938) Pres, (for mail) Genesee Heating Service, Inc., 950 Mercantile Bldg., and 140 Windemere Rd., Rochester, N. Y. DICKENSON, Frederick R. (Af 1936; A 1934) Mgr. Industrial Relations (for mail) American Blower Corp., 6000 Russell St.. Detroit, and 715 Pilgrim Rd., Birmingham, Mich. DICKENSON, Malcolm E. (Af 1936) Vice-Pres. & Mgr. (for mail) Livingston Stoker Co., Ltd., 78 Catharine St., N., and 964 Cumberland Ave., Hamilton, Ont., Canada. DICKEY, Arthur J. (Af 1921) Vice-Pres.. Gen. Mgr., C. A. Dunham Co., Ltd.. 1523 Davenport Rd., and (for mail) 9 Mossom- Place, Toronto, Ont., Canada. DICKINSON, Robert P., Jr. (7 1938) Warehouse Mgr- (for mail) Burnham Boiler Corp. of Ohio, 301 Brushton Ave., Pittsburgh, and 219 Meade St., Wilkinsburg, Pa. DICKSON, George P. (Af 1919) Gen. Mgr. (for mail) B. F. Sturtevant Co. of Canada, Ltd., 137 Wellington St., W., and 11 Bracondale Hill Rd., Toronto, Ont., Canada. DICKSON, Robert B. (Af 1919).Pres, (for mail) Kewanee Boiler Corp., and 145 E. Division St., Kewanee, 111. - DICKSON, Robert W., Jr. (7 1938) Sales Engr., American Blower Corp., 1433^,Oliver Bldg,. Pittsburgh, Pa. --. DIETZ, C. Fred (Af 1937) Sales Engr. (for mail). Haynes Selling Co., Inc., 1124 Spring Garden St., and 1215 Allengrove St., Philadelphia, Pa. DILL, Richard S.* (Af 1939) Assoc. Mech. Engr., , National Bureau of Standards, Washington, D. C., and (for mail) 1603 S. Springwood Dr., Silver Spring, Md. DILLENDER, Eugene A. (Af 1939) Htg. Engr;, Houston Gas & Fuel Div. of United Gas Corp., Rusk Bldg., and (for mail) 3911 Poe, Houston,Tex. DTMOR, Elton J. (Af 1933) Dist. Mgr., Holcomb & Hoke Mfg. Co., Indianapolis, Ind., and (for mail) 1387 Court Ave., Memphis, Tenn. DION. Alfred M. (Af 1937) Sales Engr. (for mail) Trane Co. of Canada, Ltd., King & Mowat Sts., and 356 Bloor St., E., Toronto. Ont., Canada. DISNEY, Melvin A. (A 1934) Pres, (for mail) ' Disney-Leffel Co., Inc.. 3323 Main St., and 6648 Kenwood, Kansas City, Mo. DISTEL, Robert E. (7 1938) Distel Heating Equipment Co. (for mail) P. O. Box 133, Lansing, and 547 Bailey St., East Lansing. Mich. DIVER, M. L. (Af 1925) Consulting Engr., P. O. Box 1016, San Antonio, Tex. DIXON, Arthur G. (Af 1928) Sales Mgr. (for mail) Modine Mfg. Co., and 442 Wolff St., Racine, Wis. DODDS, Forrest F. (Af 1920) Mgr., K. C. Branch (for mail) American Radiator & Standard Sani tary Corp., 1023 Grand Ave., and Park Lane Apts.. 4600 Mill Creek Pkwy., Kansas City, Mo. 22 ROLL OF MEMBERSHIP DODGE, Harry A. (Af 1936) Elec. Engr., S. H. Kress & Co.,-114 Fifth Ave., and (for mail)514 West End Ave., New York, N. Y. DOERING, F. L. (Af 1919) Salesman, American - Radiator & Standard Sanitary Corp., 238 Boston Ave.,'Lynchburg, VaDOLAN, Raymond G- (Af 1926; 7 1922) Secy.- Treas. (for mail) Tom Dolan Heating Co., Inc., 614 W. Grand, and 2112 West 20th, Oklahoma City, Okla. DOLSON, Charles N, (A 1937) 1945 Concord Rdv, Columbus, O. DOME, Alan G. (A 1938; 7 1936) Air Cond. Engr., Bryant Air Conditioning Corp., 915 N. Front St., and (for mail) 28 Roumford Rd., Philadelphia, Pa. DONELSON, William N. (7 1937) Htg. Engr.. Harry A. Pillen, 626 Broadway, and (for mail) 415 Probasco, Cincinnati, O. DONNELLY, James A.* {Life Members Af 1904) (Trcas., 1912-1914) Largent, W. Va. DONNELLY, Russell (Af 1923) Sales Engr.. Nash Engineering Co., Graybar Bldg., 420 Lexington Ave., New York, N. Y. DONOHOE, John B. (A 1937; 7 1935) Engr. & Estimator (for mail) B. F. Donohoe Co., 51 Albany St., Boston, and 23 Primrose St., Roslin- dale. Mass. . DONOVAN, William J. (A 1930) 2239 North 27th St., Philadelphia, Pa. DORFAN, M. I. (Af 1929) Dust Control Specialist, Pangbom Corp., 604 Chamber of Commerce Bldg., and (for mail) 1217 Malvern Ave., Pitts burgh, Pa. .' DORNHEIM, G. A. (Af 1912; 7 1906) 15 Hamilton Ave., Bronxville, N. Y. DORSEY, Francis G. (Af 1920) Engr.-Contractor (for mail) Francis C. Dorsey, Inc., 4520 Schenley Rd., Roland Park, and 212 Gittings Ave., Baltimore. Md. DOSTER, Alexis (A 1934) Vice-Pres. and Secy, (for mail) The Torrington Mfg. Co., 70 Franklin St., Torrington, and South Plains, Litchfield. Conn. DOUGHTY, Charles J. (Af 1925) Mgr. (for mail) C. J. Doughty & Co., 30 Brenan Rd., and 1202 Avenue Joffre, Shanghai, China. . DOUGLAS, Howard H. (A 1936) Air Cond. and Htg. Engr. (for mail) Southern California Edison Co., 601 W. 5th St., and 2317 Kelton Ave.. Los Angeles, Calif. DOVOLIS, Nick J. (A 1939; 7 1936; S 1935) Chicago Ave., Minneapolis, Minn. DOWDY, Rufus B. (Af 1939) Sales Engr., Haydn Myer Co., Inc. (for mail) P. O. Box 746, and 10 Thom PI., Montgomery, Ala. DOWLER, Edward A. (Af 1937) Sales Engr.. B. F. Sturtevant Co. of Canada, Ltd., 137 Wellington St., W,, and (for mail) 9 Prince Arthur Ave., Toronto, Ont., Canada. DOWNE, Edward R. (Af 1927) Chief Engr. (for mail) Bryant Heater Co., 17825 St. Clair Ave., and 18301 S. Woodland Rd., Cleveland, O. DOWNES, Alfred H. (A 1937) Draftsman. 1342M Bond St., Los Angeles, Calif. DOWNES, H. H. (Af 1923) Dist. Mgr., Mgr. Navy Equip. Div. (for mail) American Blower Corp*' 438 Woodward Bldg., Washington, D. C., and 4621 Chevy Chase Blvd., Chevy Chase, Md. DOWNES. Nate W. (Af 1917) Chief Engr. & Supt. of Bldgs., School Dist. of Kansas City. Mo., 317 Finance Bldg., Kansas City, Mo. DOWNING, Clarence B: (A 1938) Secy.-Treas., N. B. Downing Co., Jefferson Ave., and (for mail) Clark Ave., Milford, Del. DOWNS, Charles R. (Af 1936) Pres., Calorider Corp., Old Greenwich, Conn., and (for mail) 50 E. 41st St.. New York, N. Y. DOWNS. Sewell H. (Af 1931) (Council, 1936-1939) Chief Engr., Clarage Fan Co., and (for mail) 211 Creston Ave., Kalamazoo, Mich. . DOXEY, Harold E. (A 1937) Supervising Engr. (for mail) Ocean Accident & Guarantee Corp., Ltd., 308 Phoenix Bldg. and 4250 Quincy St., N. E., Minneapolis, Minn. DOYLE, Bernard J. (A 1938) Sales Engr., Weil- McLain Co., and (for mail) 1430 Collingwood Detroit, Mich. DRAKE, George M. (A 1940; 7 1936) Vice-Pres. . (for mail) George H. Drake, Inc., 218 Lexington Ave., Buffalo, and 163 Renwood Ave., Kenmore, N. Y. DREHER, Louis F. {S 1938) 4816 Margaretta Ave., St. Louis, Mo. DRESCHER, Francis E. (A 1938) Sales Engr.. , Straus-Frank Co., 1618 Fannin St., and (for mail) 2725 Beatty St., Houston, Tex. DRESSELL, Russell E. (A 1938) Mech. Engr., ` Riggs Distler Co., Inc., 216 N. Calvert St., and (for mail) 918 E. Preston St., Baltimore. Md. DRIEMEYER, Ray C. (7 1937) Sales Engr., Air- therm Mfg. Co., 1474 S. Vandeventer, and (for mail) 5410 Vernon Ave., St. Louis, Mo. DRINKER, Philip* (Af 1922) Prof, of Industrial Hygiene (for mail) Harvard School of Public Health, 55 Shattuck St., Boston, and Newton Center, Mass. DRISCOLL, Marvin G. (Af 1937) Vice-Pres. (for mail) Bryant Equipment Co., Inc., 1725 Rhodes Haverty Bldg., and 20 Collier Rd., Atlanta, Ga. DRISCOLL, William H.* (Af 1904) {Presidential Member) (Pres., 1926; 1st Vice-Pres.. 1925; 2nd Vice-Pres., 1924; Treas.. 1923; Council, 1918 1927) Vice-Pres. (for mail) Carrier Corp*. Syra cuse. N. Y., and 50 Glenwood Ave., Jersey City N. J. DROPPERS, C. J. (A 1937) Partner, Wichita Insulation Co., and (for mail) 566 W. Douglas Ave., Wichita, Kan. . DRUM, Leo J., Jr. (7 1939) Sales Engr., York Ice Machinery Corp- (for mail) P. O. Box 182, and 1448 Milner Crescent, Birmingham, Ala. DU BOIS, Louis J. (Af 1931) Air Cond. Engr- York Ice Machinery Corp., 117 S. 11th St., St. Louis, Mo., and (for mail) 7451 Bland Drive, Clayton, Mo. DUBRY, Ernest E. (Af 1924) Asst. Supt., Central Heating, Detroit Edison Co., 2000 Second Ave.. and (for mail) 9116 Dexter Blvd., Detroit, Mich! DU CHATEAU, Manuel F. (7 1938) Sales Engr. (for mail) Crane Co., 824 Broadway, Cincinnati, and 8 Bachman. Greenhills, O. DUFAULT, Felix H. (A 1936) Mgr. Furnace Div., Quebec & Maritime Provinces (for mail) General Steel Wares. Ltd., 2355 Delisle St., and 5115 Bordeaux St., Apt. 6, Montreal, P. Q-. Canada. DUGAN, Thomas M. (Af 1920) Sanitary-Htgr Engr., National Tube Co., Fourth Ave. and Locust St., and (for mail) 1308 Freemont St.. McKeesport, Pa. DULL, Edgar J. (A 1937) Resident Inspector ofNaval Material, U. S. Navy (for mail) c/o York Ice Machinery Corp., York, Pa., and 3614-3rd St., Brooklyn, Baltimore, Md. DULLE, WUlferd L. (7 1936) Asst. Secy., E. E. Souther Iron Co., 1952 Hienlen Ave., St. Louis, and 2910 Lincoln Ave., Normandy, Mo. DUNCAN, William A. (A 1930) Mgr.. Process Service (for mail) Dominion Oxygen Co., Ltd., 159 Bay St., W., and 71 Jackson Ave., Toronto, Ont., Canada. .. DUNHAM, Clayton A.* (Af 1911) Pres, (for mail) C. A. Dunham Co., 450 E. Ohio St., Chicago, and - 150 Maple'Hill Rd., Glencoe, III. DUNNE, Russell V; D. (Af 1937) Chief Engr., International Div., Air Cond. & Ref. (for mail) Carrier Corp., S. Geddes St., and 216 Robineau Rd., Syracuse, N. Y- DURKEE, Merritt E. (A 1936 ; 7 193L) Sales Engr., 97 Overlook Rd., White Plains, N. Y. DUTCHER, Harvey S. (A 1938) Htg. & Vtg. Engr.. New York State Dept. Public -Wks., Div. of Archt., 11th Floor, State Office Bldg., and (for mail) Apt. No. 25-S, 6 S. Lake Ave., Albany. N. Y. DWYER, Thomas F. (Af 1923) Chief of Htg. & Vtg. Div. (for mail) Board of Education. 49 Flatbush Ave. Ext., Brooklyn, and 82 Iris Ave., Floral Park. L. I., N. Y. 23 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 DYER, Wilfrid S. (A 1939) Partner, ,H. W. Dyer & Son (for mall) 92 Byron St., Battle Creek, Mich. DYKES, James B. (A 1939; 7 1936) Estimator (for tpail) T. A. Morrison & Co., Ltd., 1070 Bleury St., and Apt. No. 15, 3156 Maplewood Ave., Montreal, P. Q., Canada. DYKMAN, John G. (A 1938) Owner, John G. Dykman, 205 Lane Ave., S. W., Grand Rapids, Mich. ' . E . EADE, Hugh R. (Af 1935) ArchL.(for mail) Eade & Co.. 2 Imperial Bank Bldg., and 163 Cheriton Ave., North Kildonan, Winnipeg. Man., Canada. EADIE, J. G. (Af 1909) Consulting Engr., Eadie, Freund & Campbell Co., 110 West 40th St., New York, N. Y. ' EAGLETON, Sterling P. (Af 1936) Group Supt., U. S. Government, Room 2070, Interior Bldg., and (for mail) 3522 "S" St., N. W., Washington, D. C. EARL, Warren (A 1936) Vice-Pres. & Gen. Mgr., Esko Mfg. Corp., 276 Shea PI., and (for mail) 515 Fargo Ave., Houston, Tex. EARLE, Frederic E. (Af 1937) Sales Engr. (for . mail) 520 Howard Ave., Bridgeport, and 1536 Main St., Stratford, Conn. EASTMAN, Carl B. (Af 1932; 7 1929) Sales Engr. (for mail) C. A. Dunham Co., 1500 Walnut St., . Philadelphia, and 530 Brookview Lane. Brook line. Pa. EASTWOOD. E. O. (Af 1921) (Condi, 1937-1939) Head of DepL of Mech. Engrg. (for mail) Uni versity of Washington, and 4702-l2th Ave., N. E., Seattle. Wash. EASTWOOD, Harry F. (Af 1925) Mgr. Anthracite Industries, Permanent Exhibit, Architects Sam ple Corp., 101 Park Ave., New York, and (for mail) 157 Frankel Blvd., Merrick, L. I., N. Y. EATON, Byron K. (Af 1920) Sales Mgr.. Delco Htg. & Air Cond. Dept., Major Appliance Co., 2558 Farnam St., and (for mail) 817 S. 38th St.. Omaha, Nebr. EATON, William G. M. (A 1934) Sales Engr.. Pease Foundry Co., Ltd., 227 Victoria St., and (for mail) 300 Wellesley St,, Toronto, Ont.. Canada. EBERT, William A. (Af 1920) Partner (for mail) Ebert Air Conditioning. 1026 W. Ashby, and 2151 W. Kings Highway. San Antonio, Tex. ECKART, John H. (A 1938) Salesman, Htg. Dept., Sears Roebuck & Co., 6339 Market St., and (for mail) 6012 Lawndale Ave., Philadelphia, Pa. EDELMAN, Bernard P. (A. 1935) Sales Mgr. (for mail) U. S. Air Conditioning Corp., 2101 Kennedy St., N. E., and 4024 Colfax Ave..'S.. ' Minneapolis, Minn. ' .............: EDGE, Alfred J. (Af 1938) Engr. in charge Htg. & Air Cond. (for mail) c/o John F. Reynolds, Cons. Engr., Room 316 Duval Bldg., and 2051 Herschel St.. Jacksonville, Fla. ! ; EDWARDS, Arthur W. (Af 1936) Branch Mgr., The Trane Co., 626 Broadway, and (for mail)3423 Paxton Ave.-,-Cincinnati, O; EDWARDS, Don J. (A 1933) Vice-Pres. (for mail) General Heat & Appliance Co., 596 Common wealth Ave., and 8 Devon Terrace, Boston, Mass. EDWARDS, Junius D.* (Af 1936) Asst. Dir. .of Research (for mail) Aluminum Research Labora tories, Aluminum Company of America, P. O. Box 772, New Kensington, and 536 Sixth St., Oakmont, Pa. ` EDWARDS, Lawrence V. (Af 1938) Engr., ' Buensod-Stacey Air Conditioning, Inc., 60 - E. 42nd St., New York, N. Y., and (for mail) 1631 Edmund Terrace, Union, N. J. ; EDWARDS, Paul A. (Af 1919) Pres, (for mait): The G. F. Higgins Co., 608 Wabash .Bldg.. Pittsburgh, and 3074 Pinehurst Ave.. Pittsburgh (16) Pa. ... EGGLESTON, Herbert L. (Af 1938) Mgr., Gas & Ref. Depts., Gilmore Oil Co., 2423 E. 28th St., Los Angeles, and (for mail) 1017 Cumberland Rd., Glendale. Calif. EHLERS, Jacobus (A 1939; 7 1937) Engr. (for mail) Carrier Engineering South Africa, Ltd., Box 3013, Capetown, South Africa. EHRLICH. M. William* (Af 1916) Chief Engr., Commodore Heaters Corp., 11 West 42nd St., New York, N. Y., and (for mail) 56 Ridge Rd., Lyndhurst, N. J. EICHER, HuBert C. (Af 1922) Chief, Div. of School Plant, Pennsylvania State Dept, of Public Instruction. State Capitol, and (for mail) 207 North 30th St., Harrisburg, Pa. EILS, Lee C. (7 1936) Sales Engr. (for mail) Anemostat Corp. of America, 10 E. 39th St.. p >.New York, N. Y., and 3223 Kennett Sq., Pitts burgh, EISELE, Dudley E. (A 1938) Owner (for mail) Eisele Engineering Co., 121 N. Appleton St., and 1735 N. Morrison St., Appleton, Wis. EISELE, Lewis G. (A 1937) Secy, (for mail- Eisele Automatic Heating Co., Box 309, and 602 W. Hughitt St., Iron Mountain, Mich. EISELE, William S. (A 1937) Sales Engr.. Acer & Whedon, Inc., Medina, and (for mail) 88 E. Depew Ave., Buffalo, N. Y. EISS, Robert M. (Af 1933: 7 1930) Engr.. Kim berly-Clark Corp., P. O. Box 31, and (for mail) 714 Hewitt St., Neenah, Wis. EKINGS. Robert M., Jr. (Af 1938) Engr., Air Cond. Dept., General Electric Co., 5 Lawrence St.. Bloomfield, N. J., and (for mall) 132 S. Oakhurst Drive, Beverly Hills, Calif. EKLUND, Karl G. (M 1938) Consulting.Engr. (for mail). Karl G. Eklunds Ingeniorabyra. Brunkebergstorg 15, Stockholm, and Storangen, Sweden. ELBERT, Ben F. (7 1937) Sales Engr., Sidles Co., Airtemp Div., 425 Stuart Bldg., Lincoln Nebr., and (for mail) 1008 Eighth St., Des Moines, la. ELLINGWOOD, Elliott L. (Af 1909) Cons. Mech. & Elect. Engr. (for mail) 124 W. 4th St., Los Angeles, and 210 S. Los Robles Ave., Pasadena, Calif. ELLIOT, Edwin (Af 1929) (for mail) Edwin Elliot & Co., 560 North 16th St., Philadelphia, and 403 W. Price St., Germantown, Philadelphia, Pa. ELLIOT, Gerald B. (Af 1938) Sales Engr., Frands Hankin Co., Ltd., and (for mall) 4971 Victoria Ave., Montreal, P. Q-, Canada. ELLIOTT, Irwin (A 1937) Chief Engr., Universal Oven Co., 27.1. Broadway. New York, and (for mail) 103 Penfield Ave., Croton, N. Y. ELLIOTT, Louis B. (Af 1932) Consulting Mech. Engr. (for mail) Ebasco Services, Inc., 2 Rector ' St., New York, N. Y. ELLIOTT, Norton B. (A 1934) Sales Engr., American Blower Corp., 632 Fisher Bldg., Detroit, Mich. ELLIS, Frederic R. (Af 1913) Buerkel & Co., Inc.. 18-24 Union Park St.. Boston, and (for mail) 131 Beacon St., Hyde Park, Mass. ELLIS. Frederick E. (Af 1923) Sales Mgr. (for mail) Imperial Iron Corp., Ltd., 30 Jefferson Ave., Toronto, and 9 Princeton Rd., Toronto-2 Ont., Canada. ELLIS. Gershom P. .(Af 1935) Chief Engr. (for -mail) Board of Public Education, 341 Bellefield Ave., and 6601 Dalzell Place, Pittsburgh, Pa. ELLIS. Harry W. (Life Member; Af 1923; A 1909) Chairman Board of Directors, Johnson Service Co. (for mail) 2317 E. Wyoming PL, Milwaukee. Wis. .' ELLIS, Lester W. (A 1938) 406 W. 34th St., Kansas City, Mo. .. ' ELWOOD, Willis H. (Af 1936) Branch Mgr., Holland Furnace Co., 209 King St., Ithaca, N. Y. EMANUELS, Mason (J 1939) Sales Engr., ` Pacific Scientific Co., 25 Stillman St., -San Frandsco, and (for mail) 779 Vincente Ave., Berkeley, Calif. ' EMERSON, John J. (A 1939; 7 1938) Sales Engr., 424 Sherbrooke St., W.. Apt. 35, Montreal. P. Q.. Canada. :- '; ' ROLL OF MEMBERSHIP EMERSON, Ralph R. (Af 1922) Pres., Emerson EVEREST, R. Harry (Af 1935) Sales Engr., Swan Goodyer Co., 107 Arlington St., Boston, and (for mail) 44 Whitney Rd., Newtonvilie, Sheldons, Ltd., Galt, and (for mail) 235 Waterloo St.. Preston, Ont., Canada. Mass. ` EMMERT, Luther D. (Af 1919) Repr. (for mail) Buffalo Forge Co., Room 1909, 20 N. Wacker Drive, Chicago, and 1704 Hinman Ave., Evans ton. 111. . EVERETTS, John, Jr.* (Af 1938; A 1935; 7 1929) Engr.', Commercial & Air Cond. Sales Div. (for mail) - Frigidaire Div., General Motors Sales Corp., 300 Taylor SL, and 110 Oak Knoll Dr., Oakwood, Dayton, O. . EMSWILER, John E.* (Af 1917) Prof, and Chair man, Dept, of Mech. Engrg. (for.mail) University of Michigan, and 1303 Granger, Ann Arbor, Mich. EWENS, Frank G.* (Af 1937) Instructor in Mech. Engrg. (for mail) University of Toronto, Mechan ical Bldg., and 83 Madison Ave., Toronto, Ont., ENDERS, Clarence E. (A 1938) Mgr.-Engr. (for mail) Electrol Oil Burner Co., 424 E. Burnside, and 1813 S. E. 60th Ave., Portland, Ore. - . Canada. EZZ EL DIN, Kamal (7 1938) 78 Helwan St., Mounirah, Cairo, EgypL ENGDAHL, Richard B.* (7 1938) Special Re search Asst, (for mail) University of Illinois, 102 Mech. Engrg. Lab., and 607 Ohio, Urbana, 111. F ENGLE, Alfred (A 1923) Secy, (for mail) Jenkins Bros., 80 White St., New York, and 1 Edgewood Rd., Scarsdale, N. Y. ENGLISH, Harrold (Af 1935; A 1930) Pres, (for mail) English & Lauer, Inc., 1978 S. Los Angeles St., and 515 S. Norton, Los Angeles, Calif. ENSIGN, Willis A. (Af 1935) Vice-Pres.. Frontier Engineering Corp., 986 Ellicott Square Bldg., Buffalo, and (for mail) Shadagee Rd., Eden, N. Y. FABER, Dr. Oscar (Af 1934) Consulting Engr. (for mail) Romney House, Marsham St., West minster, London and Hayes Court, Kenley. Surrey, England. FABLING, Walter D. (A 1937) Sales Mgr. (for mail) Sterling Electric Motors, Inc., 5401 Tele- graph Rd., Los Angeles, and 1950 Del Mar Ave.. San Marino, Calif. EPPLE, Arnet B. (7 1934) Industrial Drying Engr., B. F. Sturtevant Co., Hyde Park, Boston, and (for mail) 247 Winter SL, Norwood, Mass. ERICKSON, E. Vincent (Af 1936) Asst, to Pres, (for mail) Wm. H. Keller, Inc., and 708 Sheldon Rd., Grand Haven, Mich. FAGIN, Daniel J. (Af 1932) Htg. Engr., Laclede Gai Light Co., 1017 Olive SL, St. Louis, Mo. FAHNESTOCK, Maurice K.* (Af 1927) Research AssL Prof, (for mail) University of Illinois. 214 M. E. Laboratory, and 701 W. California St., Urbana. Ill, ERICKSON, Harry H. (A 1929) Sales Engr. (for FA1LE, Edward H. (Af 1934) Designing and Con mail) Haynes Selling Co., 1124 Spring Garden struction Engr. (for mail) 608 Fifth Ave., New St., and 217 W./Tulpehocken St., Philadelphia, York, N. Y., and R. F. D. 1, Westport, Conn. Pa. ' FALK, David S. (7 1937) Sales Engr., The Trane ERICKSON, Martin E. (A 1926) Supt. Main Co., 8316 Woodward. Detroit, and (for mail) tenance, Board of Education, and (for mail) 809 E. Kingsley SL. Ann Arbor, Mich. 1533 South 74th St., West Allis, Wis. FALTENBACHER, Harry J. (Af 1930) Pres., ERICSSON, Eric B. (Af 1933) Engr.. Board of Harry J. Faltenbacher, Inc, 235 E. Wister SL. Education, and (for mail) 605 West 116th St., Philadelphia, Pa. Chicago, III. FALVEY, John D. (Af 1922) Consulting Engr.. ERIKSON. Harald A. (Af 1939) Vice-Pres., A. B. (for mail) 316 N. Eighth SL, St. Louis, and Svenska Flaktfabriken, Kungsgatan 16-18, Stock 6636 Pershing Ave., University City, Mo. holm 7, and (for mail) Nockebyvagen 61, Nockeby, Sweden. FAMILETTI, A. Robert (Af 1938; 7 1930) Assoc. Mech. Engr., Industrial Dept., Navy Yard, ERISMAN, Percival H., Jr. (Af 1936) Chief Engr. and (for mail) 2230 Tasker St., Philadelphia, Pa. (for mail) Washington Refrigeration Co., 1733 14th SL, N. W., Washington, D. C., and Belle Haven, Alexandria, Va. FARBER, Louis M.* (A 1940'; 7 1936) Engr. (for mail) Natkin & Co., 1800 Baltimore, and 3714 Flora Ave. Kansas City, Mo. ESCHENBACH, Samuel P. (7 1935) Sales Engr. (for mail) American Blower Corp., 135 Spring St., and 268 Dartmouth St., Rochester, N. V. FARLEY, W. F. (Af 1930) Sales Repr., American. Radiator & Standard Sanitary Corp., 50 West 40th SL, New York, and (for mail) 28 Elm St., ESPENCHIED, Frederic F. (Af 1939) Repr., New Rochelle, N. Y. American Air Filter Co. (for mall) Hill Bldg., FARNES, Bert W. (A 1938) Vice-Pres. & Sales and 3373 Stuyvesant PL, -N. W., Washington, D. C. Mgr. (for mail) Control Equipment Co., 304 Selling Bldg., and 3565 N. E. Hollyrood Court, ESTEP, Leslie G. (Af 1936) Special Assignment, Portland, Ore. Kelvinator Div., Nash-Kelvinator Corp., 14250 Plymouth Rd., and (for mail) 14909 Marlowe Ave.. Detroit, Mich. FARNHAM, Roswell (Af 1920) (Council. 1927 .1933) Dist. Mgr., Engrg. Sales (for mail) Buffalo Forge Co., P. O. Box 985, and 5 Clarendon Place. ESTES, Edwin. C. (A 1936) Mech. Draftsman Buffalo, N. Y. (for mail) Railway Transportation, Rm. 820 FARRAR, Cecil W. (Af 1920; A 1918) (Treas.. Northern Pacific Ry., Gen. Office, St. Paul, and Victoria Ave., Mendota, Minn. 1930: Council. 1930) Vice-Pres., W. A. Case & Son Mfg. Co., 31 Main SL, and (for mail) 29 ETLINGER. Martin J. (7 1936) Sales Mgr., The Oakland Place, Buffalo, N. Y. Lento Press, 441 Pearl St., and (for mail) 3026 Bainbridge Ave., New York, N. Y. FARROW, Ernest E. (A 1938) Pres.. E. E. Farrow, Inc., 2808 Maplelawn Rd., and (for mail) EUTSLER. Eugene E., Jr. (7 1938) Engr. (for 1518 Kings Highway, Dallas, Tex. mail) Buffalo Forge Co., 490 Broadway, and 375 Richmond Ave., Buffalo. N. Y. FARROW. Hollis L. (7 1937) Service & Instal lation Mgr., Sprague, Breed, Stevens & Newhall. EVANS, Bruce L. (Af 1938; A 1937) Designing Inc., 135 Broad SL, and (for mail) 910 Lynnfield Engr. (for mail) Oil Heat, Inc., 3217 Locust St., St., Lynn, Mass. and 6322 Pershing Ave., St. Louis, Mo. FATZ, Joseph L. (Af 1935) Htg. and Vtg. Engr., EVANS, Edwin C. (Af 1919) Mgr., Syracuse Office Board of Education, Room 536, 228 N. LaSalle (for mail) B. F. Sturtevant Co., 607 Eckel Bldg., St., and (for mail) 5914 W. North Ave., Chicago. and 307 Montgomery St., Syracuse, N. Y. 111. . EVANS, William A. (Af 1918) Dist. Mgr., Aerofin Corp., 1121 Fidelity Bldg., Cleveland, O.. EVELETH, Charles F.* (Af 1911) Air Cond. Engr., Smith & Oby Co., 6107 Carnegie Ave., and (for mail) 2030 East 115th St., Cleveland, O. FAUST, Frank H.* (Af 1936; 7 1930) Mgr., Commercial Engrg. Section. Air Cond. & Com mercial Refrigeration DepL (for mail) General Electric Co., 5 Lawrence St., Bloomfield, and 239 Vreeland Ave., Nutley, N. J. 25 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 FAXON, Harold C. (Af 1937) Engr., Appliance Section (for mail) Borneo Co., Ltd., Mercantile Bank. Bldg., and 73 Grange Rd., Singapore, Straits Settlements. FAY, Frank C. (Af 1925) Engr. (for mail) Raisler Heating Co., 129-31 Amsterdam Ave., New York, and 92-17-54th Ave.. Elmhurst, L. I., N. Y. FEAR, S. Lome (Af 1938) Asst. Mech. Engr. (for mail) H. E. P. C., 620 University Ave., Toronto 2, and 18 Vesta Drive, Toronto 10, Ont., Canada. FEBREY, Ernest J. (Life Member; M 1903) Pres, (for mail) E. J. Febrey & Co., Inc., 616 New York Ave., N. W., and 2331 Cathedral Ave., N. VV., Washington, D. C. FEDDERS. Melvin P. (AT 1938) Chief Test Engr., Minneapolis-Honeywell Regulator Co., 2747-4th Ave., S., and (for mail) 5212 W. Nokomis Pkwy., Minneapolis, Minn. FEDER, Nathan (J 1938) Prop, and Chief Engr. (for mail) East Side Sheet Metal Co., 403 E. 74th St., and c/o Bialek, 909 Beck St., New York, N. Y. FEEHAN, John B. (Life Member; M 1923) Pres.- Treas. (for mail) John B. Feehan, Inc.. 58 Spring St., Lynn, and 4 Long View Drive, Marblehead,' Mass. FEELY, Frank J. (Af 1935; A 1929) Mgr. of Sales. Taylor Supply Co., 700 Monroe Ave., Detroit, and (for mail) 950 Trombley Rd.. Grosse Pointe Park, Mich. FEHLIG, John B. (Life Member; M 1918) Pres.- Treas. (for mail) Excelsior Heating Supply Co., 528 Delaware St., and 2927 Brooklyn Ave., Kansas City. Mo. FEINBERG, Emanuel (J 1937) General Mgr.. Thermalair Engineering Co., 439 Penobscot Bldg., and (for mail) 2749 Elmhurst Ave., Detroit. Mich. FEIRN, William H. (Af 1937) Engr.. C. A. Hooper Co., 453 W. Gilman, and (for mail) Shorewood Hills, Madison, Wis. FELDERMANN, William (A 1937) Pres, (for mail) Walton Laboratories, Inc., 1186 Grove St., Irvington, and 357 Irving Ave., So. Orange, N. J. FELDMAN, A. M.* {Life Member; M 1903) Con sulting Engr., 40 West 77th St., New York, N. Y. FELDSTEIN, Harold (7 1938) Consulting & Design Engr., Federal Supply Co., 120 E. Main St., and (for mail) 1519 N. W. 24th St., Oklahoma City, Okta. FELLOWS. Julian R. {M 1938) Asst. Prof, of Mech. Engrg. (for mail) University of Illinois, 105 M. E. Laboratory, and 703 W. California, Urbana, III. PELS, Arthur B. {M 1919) Pres, (for mail) The Fels Co., 42 Union St., Portland, and Yarmouth, Me. . FELTWELL, Robert H. (Life Member; M 1905) Heating Engr., United States Radiator Corp., 2321-4tb St., N. E., and (for mail) 1370 Oak St., N. W., Washington, D. C. FENKER, Clement M. {M 1937) Designing Mech. Engr. (for mail) Edward J. Shulte, Archt., 920 E. McMillan, Cincinnati, and 2268 Feldman Ave., Norwood, O. FENNER, Everett M. (M 1936; A 1928) U. a Army Engr., War Dept., 819 New Industrial Trust Bldg.. Providence, and (for mail) 106 Edgewood Ave., Cranston, R. I. ' FENNER, N. Paul {A 1928) Dist. Office Mgr. (for mail) Hoffman Specialty Co., 130 N. Wells St., Chicago, and 168 Avon Rd., Elmhurst, 111. FENSTERMAKER, Sidney E. (M 1909) Partner (for mail) S. E. Fenstermaker & Co., 937 Archi- . tects & Builders Bldg., Indianapolis, and Carmel, Ind. FERDERBER, Dr. Murray B.* {M 1938) Fellow of Dept, of Industrial Hygiene, University of Pittsburgh Medical School, and (for mail) 5722 Fifth Ave., Pittsburgh, Pa. FERGESTAD, Marvin L. (AM938; J 1935) Sales Engr., Bark Prod. Div. (for mail) The Pacific Lumber Co. of Illinois, 35 E. Wacker Dr., and 2704 Arthur Ave., Chicago, 111. FERGUSON, Ralph R. {M 1934; A 1927; J 1925) Mgr. Air Cond. Dept., American Blower Corp., 50 West 40th St., New York. N. Y.. and (fOT mail) 160 Prospect St., East Orange. N. J. FERRARINI, Joseph {A 1939; J 1937) Staff Asst., Washington Gas Light Co., 411-lOth St., N. W., Washington, D. C., and (for mail) 1728 Queens Lane, Colonial Village, Apt, No. 180, Arlington, Va. FEYGE, Harold (Af 1937) Mfrs. Repr., 742 Market St., Room 230, and (for mail) 840 Van Ness Ave., San Francisco. Calif. FIDELIUS, Walter R. {M 1936) Sales Engr., Fitzgibbons Boiler Co., Inc.. 101 Park Ave., New York, and (for mail) 135 Amersfort Place, Brooklyn, N. Y. FIEDLER, Harry W. (M 1923) Owner (for mail) Air Conditioning Utilities Co., 8 West 40th St., New York, and 16 Dobbs Terrace, Scarsdale.N. Y. FIFE, G. Donald (M 1937; A 1931; J 1929) Air Cond. Engr., Architect of the Capitol, and (for mail) 211 Delaware Ave., Washington, D. C. FIGGIS, Thomas G. (A 1937; J 1936) Tech. Sales Engr.. J. & E. Hall, Ltd., Dartford Ironworks, Kent, England. FILLO, Frank B. (A 1934) Dist. Mgr., Minne apolis-Honeywell Regulator Co., 1134 N. Penn sylvania Ave., Indianapolis, Ind. - FINAN, James J. {Life Member; M 1923) Retired, 7214 Merrill Ave., Chicago, 111. . FINERAN, Edward V. (A 1940; J 1935) Mgr. Industrial Dept., Washington Gas Light Co., 411-lOth St., N. W., Washington, D. C., and (for mail) 305 Edgewood Ave., Silver Spring. Md. FINNERTY, John A. (/ 1937) Sales Mgr., Auto Heat & Air Conditioning Div., The Herman Nelson Corp., Moline, 111., and (for mail) 28 Ainsworth St., Roslindale, Mass. FINNEY, Brandon {M 1937) Tech. Engr.. Southern Water Heater Corp., 1900 N. Alameda. Compton, and (for mail) 721 Via de La Paz. Pacific Palisades, Calif. FINNIGAN, WUHam T. {M 1939) Sr. Partner (for mail) Finnigan Bros., 1421 S. E. 20th Ave., and 1634 S. E. 29th Ave., Portland, Ore. FIRESTONE, Maurice T. {M 1939) Mgr.. Carrier Air Cond. Div. (for mail) The United Clay Products Co., 931 Investment Bldg., and 1365 Rittenhouse St., N. W.. Washington, D. C. FISCHER, Lawrence {J 1937) Production Engr. (for mail) Anemostat Corp. of America, 10 East 39th St., New York, and 4823- 42nd St., Long Island City, L. I., N. Y. FISHER, John T. {J 1936) Chief Engr. (for mail) United Equipment & Supply Co., 1812 M St.. N. W., Washington. D. C.. and 805 Bonifant St., Silver Spring. Md. FITTS, Charles D. {M 1920) Mgr. (for mail) American Radiator & Standard Sanitary Corp., 692 Prior Ave.. St. Paul, and 2807 Dean Blvd., Minneapolis, Minn. FITTS, Joseph C. {M 1930) Secy.. Heating. Piping & Air Conditioning Contractors National Association, 1250 Sixth Ave., New York, N. Y.. and (for mail) 215 Kenilworth Rd., Ridgewood, N. J. FITZ, Jean Chandler {M 1924) 405 Webster Ave., New Rochelle. N. Y. FITZGERALD, Matthew J. {M 1934) SecyTreas., Standard Asbestos Mfg. Co., 820 West Lake St., Chicago, and (for mail) 1117 N. Linden Ave., Oak Park, III. FITZGERALD, William E. {J 1936; S 1935) Secy.-Treas. Engr. (for mail) Fitzgerald Plbg. & Htg. Co., Inc., 939-41 Louisiana Ave., and 435M Herndon, Shreveport, La. FITZSIMONS, J. P- (A 1940; J 1934; S 1932) Mgr. Air Cond. Dept, (for mail) Trane Co. of Canada. Ltd., 4 Mowat Ave., and 927 St. Clair Ave., W.. Toronto, Ont., Canada. FLANAGAN, James B. (A 1939) Sales Mgr. (for mail) Warden-King, Ltd., 2104 Bennett Ave., and 4244 Westhill Ave., Montreal, P. Q., Canada. 26 ROLL OF MEMBERSHIP FLARSHEIM, C. a. (A 1940; J 1933) Pres, (for mail) Clarence A. Flarsheim, Inc., 201-207 Pershing Rd.. and 3720 Holmes St., Kansas City, Mo. FLEAK, William D. (A 1938) Laboratory Engr., Refrigeration & Air Conditioning Institute, 2141 Lawrence Ave., and (for mail) 4535 N. Mozart SL, Chicago, 111. FLEISHER. Walter L* {M 1914) (2nd Vice-Pres.. 1939; Council, 1936-1939) Consulting Engr. (for mail) 11 West 42nd St., New York, and New City, N. Y. FLINK, Carl H. {M 1923) Mech. Engr. (for mail) American Radiator & Standard Sanitary Corp., 8007 Joseph Campau Ave., and 5959 Yorkshire Rd.. Dctroij, Mich. FLINN, George S. {J 1936) Engr., W. F. Slater Engineering Corp., 664 Union Ave., and (for mail) 190 w. Avalon, Memphis, Tenn. FLINT, Coll T. (Af 1919) Sales Mgr. (for mail) H. B. Smith Co., 640 Main St.. Cambridge, and 56 Brantwood Rd., Arlington, Mass. FLORETH, John J. {M 1939) Sales Mgr., Air Cond. Div., Westerlin & Campbell Co., 1113 Cornelia Ave., and (for mail) 5718 N. Richmond Ave., Chicago, 111. FOERSTNER, George C. (A 1938) Mgr., Am^na Society, Amana, la. FOLEY, Daniel F, {M 1939; A 1937) Sales Engr.. U. S. Supply Co.. Kansas City, Mo., and (for mail) 25 Wint Ave., Fort Leavenworth, Kan. FOLEY, John J, (A 1938) Pres, (for mail) Weathennakers (Canada) Ltd., 593 Adelaide St., W., and 46 Castle Knock Rd., Toronto, Ont.. Canada. - FOLEY, J, Lester {M 1938) Preapitron Specialist, Westinghouse Electric & Mfg. Co., 306 Fourth Ave., Pittsburgh, Pa., and (for mail) 3567 Reidham Rd.. Shaker Heights, O. FOLLETT, Thomas L. {J 1940; S 1936) 10900 Euclid Ave., Cleveland, and (for mail) 306 N. Main St., Hudson, O. FOLSOM, Rolfe A. {M 1938) Vice-Pres. (for mail) W. R. Ames Co.. 150 Hooper St., San Francisco, and 2411 Easton Drive, Burlingame. Calif. FOOTE, Earl E. (Af 1936) Genl Supt., Consumers Central Heating Co., 108 East 11th St., and (for mail) 3412 North 28th St., Tacoma, Wash. FORBES, Homer B., Jr. {S 1938) Student. Purdue University (for mail) 690 Waldron St., W. Lafayette, Ind., and 3218 Balmoral Ave., Chicago. 111. FORDERBRUGGEN, Kevin J. {J 1938) Engr. (for mail) Minn. Valley Natural Gas Co., 222 S. Front St., and Ben Pay Hotel, Mankato, Minn. FORFAR, Donald M. {M 1917) Mech. Engr., Grinnell Co., Inc.. 240-7th Ave., S., and (for mail) 4817 Emerson Ave., S., Minneapolis, Minn. FORRESTER, Charles M. (A 1937) Air Cond. Sales Mgr. (for mail) Gurney Foundry Co., Ltd., 4 Junction Rd., and 77 Collegeview Ave., Toronto, Ont., Canada. FORRESTER, Norman J. (A 1936) Mgr. Con . tract Div., Garth Co., 750 Belair Ave., and (for mail) 4800 Westraore Ave., Montreal, W., P. Q., Canada. FORSBERG, William (Af 1919) Secy. & Supt. (for mail) The Hopson & Chapin Mfg. Co.. 231 State St., New London, and Quaker Hill, Conn. FORSLUND, Oliver A. {M 1936) Gen. Mgr. and Partner, Forslund Pump and Machinery Co., 1717-19 Main St., and (for mail) 10$th St. & State Line. Kansas City, Mo. FOSS, Edwin R. (A 1936) Dist. Mgr. (for.mail) The Powers Regulator Co., 407 Bona Allen Bldg., and 257 Bolling Rd., N. E., Atlanta, Ga. FOSTER, Charles {M 1923) Consulting Engr. (for mail) 316 Medical Arts Bldg., and 2831 East 1st St., Duluth, Minn. FOSTER, James M. (Af 1930; A 1920) Owner (for mail) 4526 Olive St., St. Louis, and 7021 Lindell Ave., University City, Mo. FOSTER. John G. {J 1938) Sales Engr- (for mail) Air Conditioning Utilities Co., 8 West 40th St., and 3635 Sedgwick Ave., New York, N. Y. FOSTER, Philip H. (A 1937) Business Mgr. (for mail) Hudson Bay Plumbing Co., Flin Flon, Man., Canada. . FOULDS, P. A. L. (Af 1916) Partner (for mail) Hubbard. Rickerd & Blakeley, Cons. Engrs.. 110 State St.. Boston, and 72 Whitin Ave., Point of Pines, Revere, Mass. FOWLES, Harry H. (A 1940; J 1934) Htg. Engr. (for mail) Carman-Thompson Co., 12-14 Lincoln St., Lewiston, and 176 Summer St., Auburn, Me. FOX, Ernest (Af 1935) Asst, to Engr. (for mail) C. A. Dunham Co., Ltd., 1523 Davenport Rd., and 409 Glenholme Ave., Toronto, Ont., Canada. FOX, John H. (Af 1935) Sales Engr. (for mail) Minneapolis-Honeywell Regulator Co., Ltd., 117 Peter St., and 37 Macdonell Ave., Toronto, Ont., Canada. FOX, William K. (A 1939) Supt., Northwest Stove Works, 2345 S. E. Gladstone St., and (for mail) 6112 N. E. Prescott St., Portland. Ore. FRANCIS, Paul E. (Af 1937) Asst. Mgr. of Sales Northwestern Fuel Co., E-1203 First National Bank Bldg., St. Paul, and (for mail) 5115 S. Colfax Ave., Minneapolis, Minn. FRANCK, Peter {J 1938) Secy., Tiltz Air. Con ditioning Corp., 230 Park Ave., New York, and (for mail) 3311A 69th St., Jackson Heights, L. I.. N. Y. FRANK, John M. (Af 1918; A 1912) Pres, (for mail) llg Electric Ventilating Co., 2850 N. Crawford Ave., Chicago, and 1152 Chatfield Rd.. Hubbard Woods, 111. FRANK, Olive E.* (Af 1919) Vice-Pres., Frank Heaters, Inc., 150 Railroad Ave., and (for mail) 288 Graham Ave., Paterson, N. J. FRANKEL, Gilbert S. (Af 1926) Mgr., Federal and Marine Dept, (for mail) Buffalo Forge Co., 640 Woodward Bldg., and 3601 Connecticut Ave., Washington, D. C. FRANKLIN, Ralph S. (Af 1919) Pres.-Treas. (for mail) Albert B. Franklin, Inc., 38 Chauncy St., Boston, and 320 Grove St., Melrose. Mass. FRANKLIN, Sam H., Jr. (A 1938) Prop, (for mail) S. H. Franklin, Jr., Heating Contractor, 921 Main St., and 204 Colonial Court, Lynch burg. Va. FRASER, James J. (A 1936) Director (for mail) Honeywell-Brown, Ltd., Wadsworth Rd., Perivale Greenford, Middlesex, and 29 Wellesley Rd., Strawberry Hill, Twickenham, England. ' FRAZIER, J. Earl (A 1936) Vice-Pres. and Treas. (for mail) Frazier-Simplex, Inc., 436 East Beau St., and 417 East Beau St., Washington, Pa. FREDERICK, Holmes W. (Af 1937) Asst. Htg. Engr., Cornell University, Morrill Hall, and (for mail) 103 Harvard Place, Ithaca, N. Y. FREDERICK, Kendall C. (A 1938) (for mail) Major Appliance Co., 2558 Faraam SL, and 606 S. 32nd Ave., Omaha, Nebr. FREDERICK. Walter L. (A 1937) Pres, (for mail) Bryant Air Conditioning Corp., 1626 K St., N. W., and 15 Abingdon Rd., Washington, D. C. FREEMAN, Alfred W. (/ 1940; 5 1939) Gen. . Mgr., The Freeman Co., 119 Greenpoint Ave., Brooklyn, and (for mail) 31-05 88th St., Jackson Heights, L. L, N. Y. FREEMAN, Edwin M, (A 1937) Vice-Pres. & Sales (for mail) Canadian Asbestos Co., 316-322 Youville Sq., and 66 Courcelette Ave., Montreal, P. Q., Canada. FREEMAN, J. Albert (A 1940; J 1938) Partner, . Engr. (for mail) Western Engrg. Co., 1623 S. E. 11th Ave., and 3143 N. E. Wasco St., Portland, Ore. FREEMAN, John C. (A 1940; J 1936) Associate Mech. Engr. (for mail) Div. of Architecture, and 2214- 23rd SL, Sacramento, Calif. FREITAG. Frederic G. (Af 1932) 9 Harrison St.. Mt. Vernon, N. Y. FREITAS. Leo J. (A 1938) Sales Engr. (for mail) Fedders Manufacturing Co., Inc., 57 Tonawanda St., and 307 Summer SL, Buffalo. N. Y. FRENCH. Donald (Af 1926) Vice-Pres. in Charge of Engrg. (for mail) Carrier Corp., 302 S. Geddes St., and 618 Rugby Rd., Syracuse, N. Y. 27 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 FRENTZEL, Herman C. (Af 1936) Chief Engr.. The Heil Co., 3000 W. Montana St., and (for mail) 4363 N. Wildwood Ave., Milwaukee, Wis. FRIED, Harold V. (A 1935) Sales Engr. (for mail) Florida Power & Light Co., and 1775 S. W. 10th St., Miami, Fla. FRIEDLINE, James M. (J 1937) Engr., General Air Conditioning Corp., Paramount Bldg., and (for mail) 1811-5th Ave., S. E., Cedar Rapids, la. FRIEDMAN. Arthur (A 1936) (for mail) Air Controls. Inc., 1933 West 114th St.. Cleveland, and 15700 S. Moreland Blvd.. Shaker Heights. O. FRIEDMAN, D. Harry, Jr. (Af 1936) Air Cond. Engr. (for mail) Peoples Water and Gas Co., 15th & Washington Ave., and 1620 Pennsylvania Ave., Apt. 201, Miami Beach, Fla. FRIEDMAN, Ferdinand J.* (Af. 1921) Cons. Engr. (for mail) McDougall & Friedman, 1221 Osborne St., Montreal. P. Q-. Canada, and 31 Union Square, New York, N. Y. FRIEDMAN, Milton (A 1939; J 1935; 5 1933) c/o H. F. Klawuhn, Gent. Contractor, 34-24 82nd St., Jackson Heights, L. I., and (for mail) 333 West End Ave., New Yoik. N. Y. FRIMET, Maurice (/ 1936) Engr., S. I. Heating & Air Cond. Co., 452 Richmond Terrace, and (for mail) 15 Mundy Ave., West Brighton, S. I., N. Y. FRITZ, Charles V. (J 1936; 5 1933) Supt. and Estimator, Charles F. Frit* (for mail) 67 W.- Merrick Rd., and 26 Cottage Court, Freeport, L. I.. N. Y. \ FROEL1CH. H. Alien (A 1939) Gen. Mgr., The GlenAire Cooler Co.. 133)1 W. Seventh St., and (for mail) Box 404, Junction City, Kan. FUKUI, Kunitaro (Af 1926) Auditor, Oriental Carrier Engineering Co., Ltd., Toyo Menka Bldg.. Koraibashi-Higashi-ku, Osaka, Japan. FULLER, Charles A. (Af 1913) Consulting Engr. (for mail) Slocum & Fuller, Cora. Engrs., 18-E. 41st St., New York, N. Y. FULLER, Elbrldge W. (Af 1938) Mpr., Business & Industrial Air Conditioning. Frigidaire Corp... Taylor St., and (for mail) 1916 Emerson Ave., Dayton, O. ` FUNCK. Elmer H. (Af 1939; A 1928; / 1926) Sales Mgr. (for mail) Johnson Fan & Blower Corp., 1319 W. Lake SL, and 4545 Hamilton Ave., Chicago, 111. FUNK, Donald S. (A 1940) Pres., National Standard Air Products Co., 325 W. Huron-St., Chicago, and 530 Washington Blvd.. Oak Park, 111. ' G GABBARD. Frederic W. (J 1938) Engr. (for mail) Crystal Ice & Cold Storage Co., and 248 N. Central Ave., Glendale, Ariz. GABLE, H. Raymond (A 1939) Engr., Lonergan Mfg. Co., 704 Clark St., and (for mail) 600 E. Erie St., Albion, Mich. GAIR, Kenneth B. (j 1939) Sales Engr., B. F. Sturtevant Co. (for mail) 840 Kalamazoo Ave.. (XGrand Rapids, Mich. GALE, Hamilton A. 1939; J 1936) Engr.. Wallace Stebbins & Sons, Inc., 100 S. Charles St.,' Baltimore, and (for mail) Murray Hill*, Annapolis,. Md. ,, GALLAGHER, Frank H. (A 1938) Asst. Chief Engr., Board of Public Education, Forbes St. at Bellefield Ave., and (for mail) 2727 Strachan Ave., Pittsburgh, Pa. . GALLIGAN, Andrew B. (Af 1921) 716 South 51st St., Philadelphia, Pa. GALLOWAY, James F. (A 1938; S 1934) General Electric Co., 570 Lexington Ave., New York, and (for mail) 117-01 Park Lane, S., Kew Gardens, L. L, N-Y. ` GAMBLE, Cary B. (Af 1939; A 1935) Consulting Engr. (for mail) Leo S. Weil & Walter B. Moses. 427 S. Peters St., and 732 St. Peter St., New Orleans, La. ,,,, GAMM1LL, Oscar E., Jr. (A 1937; J 1930) Sales Engr. (for mail) Carrier Corp., 1413 Hibernia Bank Bldg., and 5515 Magnolia St.. New Orleans, La. GANGE, Frank B. (Af 1937) Managing Director, Gordon & Co., Ltd., 185 Yuen Ming Yuen Rd., Shanghai, China. SL,GANNON, Russell R. (Af 1939) Sales Engr. (for mail) Russel] R. Gannon Co., 519 Main and 1824 Fairfax Ave., Cincinnati, O. GANT, H. P.* (Af 1915) (Presidential Member) (Pres., 1923; 1st Vice-Pres., 1922; 2nd VIce-Ih-es., 1921; Council. 1918-1924) R. D. No. 1, Glen- moore. Pa. *. GARBER, William E., Jr. (J 1938) Sales Mgr., Farquar Heating Service Co., 3406 E. Tenth St., and (for mail) 915 Bosart St., Indianapolis, Ind. GARDNER, C. Rollins (A 1937) Vice-Pres. (for mail) Martyn Brothers, Inc., 911 Camp St., Dallas, and 4417 E. Lancaster, Fort Worth, Tex. GARDNER, S. Franklin (Af 1911) Pres, (for mail) Standard Engineering Co-. 2129 Eye St., N. W., and 4901 Hillbrook Lane, Washington. D.-C. GARDNER, William (A 1921) Pres, (for mail) Garden City Fan Co., 332 S. Michigan Ave., and 7836 Loomis Blvd.. Chicago, III. GARNEAU, Leo (Af 1938; J 1930) Sales Engr. (for mail) C. A. Dunham Co-. Ltd., 931 Dominion Square Bldg., and 2541 Maplewood Ave. (Apt. 2) Montreal, P. Q.. Canada. GAULEY, Ernest R. (A 1935) Pres, (for mail) Age Publications, Ltd., 31 Willcocks St., and 156 Dewhurst Blvd., Toronto, Ont., Canada. GAULT, George W. (J 1937; 5 1934) Army Officer, 2nd Lt., C. C. C- Camp. S-118, Clear- held. Pa. GAUSE, H. Chester (Af 1937) Power Sales Engr., Alabama Power Co. (for mail) 600 North 18th St., and 905 South 38th St., Birmingham. Ala. GAUSEWITZ, William H. (A 1937) Owner and Mgr., Conditionedaire. Inc., 513 Third Ave., N. E., and (for mail) 1321 W. Minnehaha Pkwy., Minneapolis, Minn. GAUSMAN, Carl E. (Af 1923) Partner, Gausman & Moore. 1026 First Natl- Bank Bldg., and (for mail) 2360 Chilcombe Ave., St. Paul, Minn. CAWTHROP, Fred H. (Af 1919) Pres., Gawthrop & Bro. Co., 705 Orange St., and (for mail) 2211 Shallcross Ave., Wilmington, Del. GAYLORD, Frank H. (Af 1921) Western Sales Mgr. (for mail) Hoffman Specialty Co.. Inc., 130 N. Wells St., Chicago, and 362 N. York St.. Elmhurst, 111. GAYMAN, Paul D. (Af 1938) Branch Mgr. (for mail) Johnson Service Co*/2142 East 19th St., Cleveland and 20875 Endsley Ave., Rocky River. O. GAYNER, James (Af 1937) Mech. Engr., G. M. Simonson, Cons. Engr., 74 New Montgomery St.. . San Francisco, and (for mail) 327 Magnolia Ave., ` Piedmont. Calif. ` GEE. William W.. Jr. (A 1940; J 1938) Engr. & Contractor (for mail) William Gee, Jr.` & Co., 133 Geary St., San Francisco, and 605 Burlin game Ave.. Burlingame. Calif. GEHRS. William (A 1939) Branch Mgr. (for mail) Johnson Service Co.. 1312 N. W. Raleigh St., and 3801 S. E. Woodward St., Portland, Ore. GEIGER, Irvin H. (Af 1919) Registered Prof. Engr. & Mfrs. Repr. (for mail) 319 Telegraph Bldg., and 240 Maclay St.. Harrisburg. Pa. GEIGER, Raymond L. (Af 1939) Assoc. Mech. Engr., War Dept., U.S.A., Fort Myer. Va.. and (for mail) 5811-14th St.. N. W., Washington, D. C. GELTZ, Ralph W. (J 1936) Air Cond. Engr.. York Ice Machinery Corp., 2700 Washington Ave., and (for mail) 14213 Glenside Rd., Cleve land, O. GENRE, E. John (A 1938) Wholesale Sales Mgr. (for mail) Tidraarsh Engineering Co., P. O. Box No. 8, Phoenix, Ariz. . GERHARD, David H. (A 1937) Power Sales Engr., Consumers Power Co., Jackson, and (for mail). 156 Allen, Alma. Mich. ^ GERMAIN, Oscar (M 1935) Htg. Expert. 1343 Blvd. St. Louis, Three Rivers. P. Q.. Canada. GERRISH, Grenville B. (A 1936; J 1930) Mgr., Fitzgibbons Boiler Co., Inc., 31 Main St.. .Cam bridge. and (for mail) Standish Rd.. Melrose. Mass. ' ROLL Of MEMBERSHIP GERRISH, Harry E. (Af 1910) (Council, 1919) Partner (for mail) Morgan-GeIrish Co., 84 S. Tenth St., 307 Essex Bldg*, and 4534 Fremont St., Minneapolis, Minn. GERSTENBERGER. Edgar J. (A 1938) Sales Engr., F. R. Dengel Co., 1134 North 4th St., and (for mail) 3824 North 17th St., Milwaukee, Wis. CETSCHOW, Roy M. (Af 1919) Pres. & Treas. (for mail) Phillips-Getschow Co., 32 W. Hubbard St.; Chicago, and 122 Woodstock, Kenilworth, 111. GHILARDI, Fernand (Af 1937) Chief Engr., Herdt et Charton. Inc., 34 Rue Godot de Mauroy, Paris, and (for mail) 12 Rue (rabrielle d'Estrees Vanves (Siene) France. CHOSE, Khagendra N. (A 1938) Consulting Engr., 39 Ramkanta Bose St., Bagh Bayar, Calcutta, India. GIIOSH, Bidhu B. (J 1939) Air Cond. Engr. (for mail) Messrs. Refrigerators (India) Ltd., 13 C, Russell St., and Galstaun Mansions, Calcutta. India. GIANNINI, Mario C. (Af 1935) Asst. Prof, of Mech Engrg. (for mail) New York University, University Heights, and 62 Park Terrace West, New York, N. Y. , GIBBONS, Michael J. (Af 1914) Owner. M. J. Gibbons Supply Co., 601-31 E. Monument Ave., and (for mail) 22 Oxford Ave., Dayton, O. GIBBS, Edward W. (Af 1919) Pres, (for mail) The Smith-Gibbs Co., 201 S. Main St., and 39 President Ave., Providence, R. I. GIESECKE, Frederick E.* (Af 1913) (1st Vice- Pres., 1939: 2nd Vice-Pres., 1938; Council,-1932- 1939) Professor Emeritus. Htg., Vtg. & Air . Cond., A. & M. College of Texas, College Station, Tex. GIFFORD, Clarence A. (A 1934) Salesman, .American Radiator & Standard Sanitary Corp., 1807 Elmwood. Buffalo, and (for mail) 78 Roycroft Blvd., Snyder, N. Y. GIFFORD, Edmund W. (Af 1938; J 1929) Chief Engr. (for mail) Airtemp Construction Corp., / 4841 Woodward Ave., and 745 Seyburn Ave., Detroit. Mich. GIFFORD, Robert L. (Life Member; M 1908) Pres., Illinois Engineering Co., Corl 2lst St. & Racine Ave., Chicago, 111., and (for mail) 1231 S. El Molino Ave., Pasadena, Calif. - GIFFORD, William R. (Af 1938; J 1936) Sales . - Engr., American Radiator & Standard Sanitary Corp., Connecticut Ave. & S St., N. W., Wash ington, D. C., and (for mail) Franklin & Dicken son Aves., College Park. Md. . GIGUERE, George H. (Af 1920) Mech.^Engr., ,. Smith, Hinchman & Grylls, 800 Marquette :>B|dg.. and (for mail) 17205- Fairport, Detroit, Mich. .* GILBERT, Leslie S. (Af 1937) Owner (for mail) Gilbert Engineering Co., 1305 Liberty Bank Bldg., and 3713 Southwestern Blvd., Dallas, Tex. GILFRIN, George F. (Af 1932) Climas Artificiales. S. A. (for mail) Edifido "La Nadonal" 902, and . Esplanada No. 715 Lomas de Chapultepe:, Mexico, D. F. ^ GILLE, Hadar B. (Af 1930) Consulting Engrl (for mall) Hugo Theorells Ingeniorsbyra, Skoldun' gagatan 4, Stockholm, and Svanhildsvagen 19, Nockeby, Sweden. GILLETT, M. C. (Af 1916) Dist. Sales Engr., Hoffman Spedalty Co., Inc., and (for mail) 6600 Rising Sun Ave., Philadelphia. Pa. GILLHAM, Walter E. (Af 1917) Consulting Engr. (for mail) 337 Law Bldg., and 3427 Bellfontain Ave., Kansas City, Mo/ GILMAN, Franklin W, (Af J935) Engr., C. F. Moores Co., 186 E. Evergreen Ave., and (for mail) 514 W. Coulter St., Philadelphia, Pa. GILMORE, John L, (A 1938) Owner, John L. Gilmore Htg.-Vtg., 1602 Kay Ave.; and (for mail) 1604 Union St., Brunswick, Ga. GILMORE, Louis A. (A 1940; J 1935; 5 1930) Vice-Pres. (for mail) John Gilmore & Co., 115 South 11th St., and 5906 McPherson Ave., St. Louis, Mo. * GINI, Aldo (Af 1933) via Correggio 18. Milano. Italy. GINN, Tony M. (Af 1935) General Mgr., Tony M- Ginn Co., 214-24 Fifth St., S., Great Falls, Mont- GITTERMAN, Henry (A 1937) Predpitron Specialist (for mail) Westinghouse Electric & Mfg. Co., 150 Broadway. New York, and Baptist Church Rd.. Yorktown Heights. N. Y. GITTLESON, Harold (A 1936) Sales Mgr.. Lariviere, Inc, 3715 St. Lawrence Blvd., Mon treal,and (for mail) 1125Lajoie Ave., Outremont. P. Q., Canada. ' GIVIN, Albert W. (A 1925) Vice-Pres. in Charge of Sales (for mail) The Gurney Foundry Co.. Ltd., 4 Junction Rd., and 219 St. Clair Ave., W., ' Toronto, Ont., Canada. GLASS, William (Af 1934) Mgr. (for mail) Partridge-Halliday, Ltd., 144 Lombard St.. Winnipeg, and 190 Braemer Ave., Norwood. Man., Canada. GLEASON, Gilbert H. (Af 1923) Partner (for mail) Gilbert Howe Gleason & Co., 28 St. ' Botolph St.. Boston, and 10 Edgehill Rd.. Winchester, Mass. GODFREY, Joseph E. (J 1938) Engr., Frigidaire Div., General Motors Sales Corp., 300 Taylor St., and (for mail) 1500 Ridgeway Rd., Dayton, O. GOEHLER, Elmer E. (A 1939) Pres, (for mail) ' Vortex Mfg- Co., 687 N. Tillamook St., and 2932 N. E. 37th Ave., Portland, Ore. GOELZ, Arnold H. (Af 1931) Pres, (for mail) Kroeschell Engineering Co.. 215 W. Ontario St.. Chicago, and 827 Greenwood Ave., Wilmette, 111. GOENAGA, Roger C. (Af 1931) Tech. Director. Ateliers Ventil (for mail) 109 Cours Gambetta, Lyon, and 33 Avenue Valioud-Ste-Foy-Ies-Lyon, Rhone, France. GOERG, Bernhard ('Af 1928) Director of Institute of Thermal Research (for mail) American Radi' ator & Standard Sanitary Corp., 675 Bronx River Rd., Yonkers, and 57 Minerva Drive, Tuckahoe, N. Y. . GOERGENS, Albert G. (A 1938) Asst. Engr., War Dept., O. Q. M. G-, Munitions Bldg., Washington. D. C., and (for mail) 817 Chalfonte Dr., Alexandria. Va. . GOFF, John A. (Af 1939) Dean (for mail) Towne Scientific School, University of Pennsylvania. Philadelphia, and 511 Cambridge Rd., Cynwyd. Pa. GOLDBERG, Moses (A 1934) Pres., Electric Motors Corp- 168 Centre St., New York, and (for mail) 885 E. 8 St.. Brooklyn, N. Y. GOLDSMITH, Elliot (J 1939) Engr. (for mail) Anemostat Corp. of America, 10 E. 39th St., New York, and 139-38-87 Rd., Jamaica. L. I., N. Y. GOLDSMITH, F. W. (Af 1936) Pres, (for mail) The W. Clasmann Go., 324 .E.' Wisconsin Ave., and 629 E. Day Ave., Milwaukee. Wis. GOLL, Willard A. (A 1937) Sato Engr., Standard Furnace Supply Co., 407 S/Tenth, and (for mail) 418 North 38th Ave., Omaha, Nebr: GOMBERS, Henry B.. {Life Member; A 1901) Secy. Emeritus. Heating, Piping and Air Con ditioning Contractors National Association, 1256 Sixth Ave., New York, N. Y., and (for mail) 160 Halstead St., East Orange, N. J. GONZALEZ, Rafael A. (Af 1936) Mgr., Appli cation Engrg. Dept, (for mail) Airtemp Div., Chrysler Corp., P. O. Box 1037, and 434 Dela ware St., DajXon, O. GOOD, Charles S. (S 1939) Studeift Mech. Engrg., P.H.V. Div., Carnegie Institute of Technology, Pittsburgh, and (for mail) 415 Rebecca Ave., Wilkinsburg, Pa. GOODRAM, William E. (Af 1939; A 1936) Partner, Goodram Bros.. 88 King St., W., Hamilton, and (for mail) R. R. 2, Freeman, Ont., Canada. GOODRICH, Charles Fl (M 1919) Andrews & Goodrich, Inc-, Boston, and (for mail) 336 Adams St., Dorchester, Mass. GOODWIN, Eugene W. (Af 1936) Sr. Mech. Engr., Public Bldgs. Administration, Procure ment Bldg.. Washington, D. C.. and (for mail) 7024 Hampden Lane, Bethesda, Md. 29 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 GOODWIN. Samuel L. {M 1924) Consulting Engr., John Eberson, 1560 Broadway, New York, N. Y., and (for mail) 247 Madison Ave., Has- brouck Heights. N. J. GORDON, Colin W. (A 1938) Vice-Pres. & Supt.. A. G. Baird, Ltd., 286 Lisgar St., and (for mail) 962 Shaw St., Toronto. Ont., Canada. GORDON, Edward B., Jr. {Life Member; M 1908) Pres., Pillsbury Engineering Co., 1200 Second Ave., S,, and (for mail) 2450 West 24th St., Minneapolis, Minn. GORDON, Henry H. W. (A 1940; J 1938) Asst. Resident Engr. (for mail) Carrier Engineering, S. A., 91 Smith St., Durban Natal, and 71 Pasadena Court, South Beach, Durban, South Africa. , GORDON, Peter B. (A 1938; 7 1935) Treas. (for mail) Wolff & Munier, Inc., 222 East 41st St., New York, N. Y., and 35 Park Ave., Bloomfield, N. J. , GORDON, William D. (A 1935) Air Cond. and Sales Engr., Hart & Cooley Mfg. Co. of Canada. Ltd., Fort Erie, N., and (for mail) 71 Chilton Rd., Toronto, Ont., Canada. GORNSTON, Michael H. (A 1923) Custodian- Engr. (for mail) Board of Education, Thomas Jefferson High School, 402 Pennsylvania Ave., Brooklyn, and 90-ll-149th St., Jamaica, L. I. N. Y. . GOSS. Matthew H. (M 1921) Partner (for mail) M. H. Goss Co.. 3536 Baldwin Ave., and 1476 Seyburn Ave., Detroit. Mich. GOSSETT, Arthur L. (A 1938) Gage Bros., 617 Red River, Austin, Tex. GOSSETT, Earl J. {M 1923) Pres, (for mad) Bell & Gossett Co., 3000 Wallace St., Chicago, and 314 Woodland Ave., Winnetka. 111. GOTHARD, William W. (A 1936) Editorial Director (for mail) Domestic Engineering, 1900 Prairie Ave., Chicago, and 1027 Arlington Ave., LaGrange, III. '. GOTSCHALL, Harry C. {M 1935) Chairman, Air Cond. Dept., Lane Technical High School, 2501 W. Addison St., and (for mail) 2953 Eastwood Ave., Chicago, 111. GOTTWALD, C. (A 1916) Pres, (for mail) The Ric-wiL Co., 1563 Union Commerce Bldg.. ' Cleveland, and 2225 Stillman Rd., Cleveland Heights, O. GOUEDY, Kenneth E. (A 1935) Member of Firm and Engr. (for mail) Modern Building Insulating Co., 411 Bona Allen Bldg., Atlanta, and 218 Columbia Drive, Decatur. Ga. GOULD, Henry E. (A 1939; J 1936) Secy, (for mail) Natkin & Co., 1800 Baltimore, and 6528 Summit, Kansas City, Mo. GOULDING, William (A 1933) Air Cond. Engr., World Broadcasting System, Inc., 711 Fifth Ave., New York, and (for mail) 782 Westminster Rd., Brooklyn, N. Y. GOUNDIE, Joseph K. {M 1938) Sales Engr.. Fritch Coal Co., 116 River St., Bethlehem, and (for mail) 1426 Walnut St., Allentown, Pa. GOWDY, Allen C, (7 1939) Estimator & DetaHer. The Huffman-Wolfe Co., 669 N. High St., and (for mail) 1007 Bryden Rd., Columbus, O. GRABER, Ernst (7 1936) Engr., Minneapolis^ Honeywell Regulator Co., 801 Second Ave., New York, and (for mail) 222 Hollywood Ave., Douglaston, L. I., N. Y. GRABMAN, Henry B. (S1938) Student (for mail) Carnegie Institute of Technology. Pittsburgh, and 355 E. Spring St., Zelienople. Pa. GRAFF, William F. (A 1937) Salesman-Engr., Standard Sanitary Mfg. Co., Grand Rapids, Mich. GRAHAM, J. Barrie (S 1939) Student, Carnegie Institute of Technology, Pittsburgh, and (for mail) 193H Meade St., Wilkinsburg, Pa. . GRAHAM, John M. (A 1937; 7 1936) Sales Engr. (for mail) B. F. Sturtevant Co., 528 Kentucky Home Life Bldg., and 1041 Cherokee Rd., Louisville. Ky. GRAHAM, William D. {M 1929; A 1925; J 1923) Mgr., Unit Heater Dept., Carrier Corp., and (for mail) 129 Circle Rd., Syracuse. N. Y. GRANKE, Arnold A. M 1939) Sales Engr.. Speakman Co., 816 Tatnall SL, and (for mail) 28 W. 4lst St., Wilmington, Del. CRANSTON, Ray O. (A 1939; 7 1935; S 1930) Secy, (for mail) University Plbg. & Htg. Co., 3939 University Way, and 4333-9 Ave., N. E., Seattle, Wash. GRANT, Walter A. (A 1933; J 1928) Dist. Chief Engr., Carrier Corp., 12 S. 12th St.. Philadelphia, and (for mail) 414 Haverford Ave., Narberth, Pa. GRAVES, Willard B. {Life Member x M 1906) Pres, (for mail) W. B. Graves Heating Co., 162 North Desplaines St., and 5920 Addison .St., Chicago, 111. GRAY, Earle W. {M 1938; A 1934) In charge of Air Cond.. Commercial Dept, (fdr mail) Okla homa Gas and Electric Co., Third and Harvey Sts., and 2125 N. W. 18th St., Oklahoma City, Okla. ` GRAY, Everett W. {M 1936) Dist. Mgr., The Trane Co., 1900 Euclid Ave., Cleveland, O. GRAY. George A. {M 1924) Branch Mgr. (for mail) C. A. Dunham Co., Ltd., 404 Plaza Bldg., and 114 Belmont Ave., Ottawa, Ont., Canada. GRAY, John W. {M 1938) Warm Air Htg.. 614 N. Water St., Bay City, Mich. GRAY, William E. {M 1922) Gray Engineering Co., and (for mail) Box 264, High Point, N. C. GREEN, Everett W. {J 1938) Junior Sales Engr. (for mail) Green Furnace and Plumbing Co., 2815 North 48th St., and 5100 Leighton Ave.. Lincoln, Nebr. GREEN. Sydney H. (7 1939) Design Engr. (for mail) Dallas Air Conditioning Co., Inc., 3500 Commerce St., and 2609 Routh St.. Dallas. Tex. GREEN, William C. {Life Member; M 1906) Dist. Repr. (for mail) Warren Wesbter & Co., 704 Race St., and 244 Erkenbrecher Ave., Cincinnati, GREENBERG. Irving (7 1940; S 1937) Air Cond. Engr., S. Greenberg, 873 Columbus Ave., New York, and (for mail) 1615 Walton Ave., Bronx, N. Y. GREENBURG, Dr. Leonard* {M1932) Executive Director, Div. of Industrial Hygiene (for mail) N. Y. State Dept, of Labor, 80 Centre SL, and 173 West 78th St., New York, N. Y. GREENLAND, Sidney F. {M 1934) Htg. & Vtg. Engr., Gee, Walker & Slater. Ltd., 3, Fitzmaurice Place, Berkeley Sq., London, W. 1, and (for mail) 9, Anerley Court, Anerley Park, London, S, E. 20, England. GREENWOOD, Orrin J. {M 1938) Consulting Engr.. 3429 W. 62nd PI., Chicago. III. GREGERSON, George {J 1939) Lab.. Engr. (Instructor) Refrigeration & Air Conditioning Institute, 2150 W. Lawrence, and (for mail) 1946 W. Wilson, Chicago, 111. GREGG, Scranton H. (A 1936) Pres., Shellenberger-Gregg Co., 2203 N. Prospect Ave., and (for mail) 5715 N. Lake Dr.. Milwaukee, Wis. GREGG, Stephen L. (A 1939; 7 1936) Sales Engr. (for mail) Potomac Electric Power Co., 10th & E Sts.. N. W., Washington, D. C., and 4828 Edgemoor Lane, Bethesda, Md. GREINER, George B., Jr. (7 1938; S1935) Engr., Wayne Crouse. Inc-, 4647 Centre Ave., and (for mail) 5515 Claybourne SL. Pittsburgh, Pa. GRIESS, Philip G. {M 1937) Mech. Engr., Voorhees, Walker, Foley & Smith. 10! Park Ave., New York, N. Y., and (for mail) 189 Walnut Ave., Bogota, N. J. ' GRIEST, Kermit C. (A 1940; J 1936) Htg. Engr. (for mail) Frank-Limbach & Co., 1722 E. Ohio St., and 437 Bausman St., Pittsburgh, Pa. GRIEVES, Thomas R. (A 1930) Branch Mgr. (for mail) U. S. Radiator Corp., 303 Crosby Bldg., Buffalo, N. Y. . GRIEWISCH, Alfred H. (A 1938) Pres, (for mail) Bayley Heating Supply Co., 2045 W. SL Paul Ave., and 2557 N. 47th SL, Milwaukee, Wis. GRIFFITH, Claude A. (A 1938) Contracting Engr., Griffith Heating & Air Conditioning Service, 632 Hill Top Drive, Cumberland, Md. ROLL OF MEMBERSHIP GRIFFITH, Herbert T. (M 1938) Designing Engr- (for mail) Lincoln Bouillon, Cons. Engr., 324-141 l-4th Ave. Bldg., and 1909-3rd Ave., W., Seattle, Wash. GRIFFITH, Joseph B. (7 1938) Sales Engr., Drayer and Hanson, 738 E. Pico Blvd., Los Angeles, and (for mail) 415 N. Sierra Vista Ave. Monterey Park. Calif. GRIMES, Fenner M. (7 1935) Engr.\ War Dept., O. Q` M. G. (Constr. Div.) Fort Myer, and (for mail) 849 S. Ivy St., Arlington. Va. GRITZAN, L. LeRoy (M 1939) Vice-Pres. & Gen- Mgr. (for mail) United Equipment & Supply Co., 1812 M St., N. W., Washington, D. C., and 208 Edgewood Ave., Silver Spring, Md- ' GROHS, Conrad E. (A 1939; 7 1938) Washington Repr. (for mail) American Gas Products, 4th & Channing Sts.. N. E., and 1349 Newton St., N. E.. Washington. D. C. GROOT, Harry W. {M 1937) Chief Engr., The Home Comfortable, Inc., 912 Baxter Ave., and (for mail) 3728 N. Western Parkway, Louisville, Ky. GROSS. Lyman C. (M 1931) Sales Engr., Minne- apolis-Honeywell Regulator Co., 2727 4th Ave-. S., ind (for mail) 5324 Oaklawn Ave., Linden Hill0 Station, Minneapolis, Minn. GROSSENBACHER. Henry E. (A 1938) Pres, (for mail) Grossenbacher Steel Furnace & Mfg. Co.. 9410-12 Milton Ave., and 9741 Lackland Rd., Overland, St. Louis Co., Mo. GROSSMAN, Franklin A. (7 1938; S 1937) Engr.. Servel, Inc., 119 N. Morton Ave.. and (for mail) 1161 E. Illinois St., Evansville, Ind. GROSSMAN, Harry E. (A 1933 ; 7 1927f Sales Repr-. Haynes Selling Co., Inc., Ridge Ave. and Spring Garden St.. Philadelphia, and (for mail) 218 Parham Rd.. Springfield, Pa. GROSSMANN, Harry A. {M 1931) Owner, H. A. Grossmann Co.. 3138 Cass Ave., and (for mail) 3122 Geyer Ave., St. Louis, Mo. GROSVOLD. Fred E. {M 1917) Owner (for mail) F. E- Grosvold Co., 417 Wisconsin St., and 711 Grand Ave., E., Eau Claire, Wis. GROVES, Samuel A. (A 1940; 7 1935) Sales Supvr.. American Radiator & Standard Sanitary Corp., 32-04 Northern Blvd., Long Island City, and (for mail) 21 Cassilis Ave., Bronxville, N. Y. GUEST, Perry L,, Jr. (A 1939) Sales Engr., Hoffman Specialty Co. (for mail) Box 506, and 716 Dover Rd., Greensboro, N. C. GULER. George D. (A 1937) Sales Engr. (for mail) Minueapolis-Honeywell Regulator Co., Wayne & Roberts St., and 334 E. Allens Lane, Phila delphia. Pa. GUMAER, P. Wilcox {M 1937) Consulting Engr., Toxic Vapors & Dusts. 25 Garden SL, West Englewood, N. J. GUNNELL, George T. {M 1937) Branch Mgr., F. J. Evans Engineering Co., 588 Peachtree St., N. E., and 595 Ashby, S. W., Atlanta, Ga. GURNEY, E. Holt (M 1929) {Presidential Mem ber) ( Pres., 1938; 1st Vice-Pres., 1937; 2nd Vice- Pres., 1936; Council, 1931-1939) Pres, (for mail) The Gurney Foundry Co., Ltd., 4 Junction Rd., and 347 Walmer Rd.. Toronto, Ont., Canada. GURNEY, Edward R. (A 1940; 7 1937) Asst, to Plant Supt. (for mail) Gurney Foundry Co., Ltd., 4 Junction Rd., and 50 Eastbourne Avel, Toronto, Ont., Canada. GUSTAFSON, Carl A. {M 1938) Sales Engr. (for mail) The Powers Regulator Co., 2720 Green- view Ave., and 6231 N. Fairfield Ave., Chicago, 111. H HAAS, Samuel L. {M 1923) Pres. & Treas. (for mail) Advance Heating & Air Conditioning Corp., 117-119 North Desplaines St., and 1513 Fargo Ave., Chicago, 111. HACH, Edjpard C. {M 1939) Asst. Chief Engr., Stanch^ Air Conditioning, Inc., 50 W. 40th St., New York, N. Y., and (for mail) 261 Seneca PI., Westfield. N. J. HACKETT, H. Berkeley {M 1921) Consulting Engr., 901 Architects Bldg., 17th and Sansom Sts., and (for mail) The Lennox, 13th and Spruce Sts., Philadelphia, Pa. HADEN, G. Nelson {M 1934; A 1928; 7 1922) Chairman and Managing Dir. (for mail) G. N. Haden & Sons, Ltd., 19-29 Woburn PI., London, - W. C. 1, and 36 Wildwood Rd., London, N. W. 11, England. - HADEN, William N. {Life Member; M 1902) Retired Chairman, G. N. Haden &. Sons, Ltd., 19-29 Woburn PL, London W. C. 1, and (for mail) Arnolds Hill, Trowbridge, England, HADJISKY, J. N. {M 1930) Consulting Engr., 744 Bates SL, Birmingham, Mich. HAERLE, Robert A. (A 1938) Mech. Engr., Bayley Blower Co., 1817 S. 66th St., and (for mail) 1438 Humboldt Ave., Milwaukee, Wis. HAGAN, William V. {M 1938; A 1933; 7 1926) Secy., V. J. Hagan Co., and (for mail) 1811 Jones St.. Sioux City, la. HAGEDON. Charles H. {M 1919) Partner (for mail) S. E. Fenstermaker & Co., 937 Archt. & Bldrs. Bldg., and 4156 Broadway, Indianapolis,. HAHN, Roy F. (7 1936) Air Cond. Engr. (for mail) Advance Refrigeration. Inc., 350 Peachtree St., and 435-10th St., N. E-. Atlanta, Ga. HAINES. John J. (M 1915) Pres, (for mail) The Haines Co., 1931 w. Lake St., Chicago, and 623 17th Ave., Maywood, III. HAITMANEK, Louis M. (A 1938) Sheet Metal Worker, 217 Rose St.. Newark, N. J. HAJEK. William J. (M 1932) 372 W. Johnson St., Philadelphia, Pa. HAKES. Leon M. {M 1932; 7 1929) Dist. Repr. (for mail) Warren Webster & Co., 210 Reynolds Arcade Bldg., and 144 Inglewood Drive, Roches-' ter. N. Y. HALE, Fred J. {M 1936) Mgr. (for mail) Empire Sheet Metal Works, Ltd.. 1606 West First Ave., and 3606 Point Grey Rd.. Vancouver, B. C., Canada. HALE, John F. {Life-Member', M 1902) {Presi dential Member) (Pres.. 1913; 1st Vice-Pres., 1912; Board of Governors, 1908-1910, 1912-1913) Dist. Mgr. (for mail) Aerofin Corp., Room 704, 111 W. Washington St., Chicago, and 400 S. LaGrange Rd., LaGrange, 111. HALEY, Harry S-* {M 1914) Consulting Engr., Partner (for mail) Leland & Haley, 58 Sutter St., . and 735-2l8t Ave., San Francisco, Calif. HALEY, Robert T. (A 1938) Supervisor of House Heating (for mail) Minneapolis Gas Co., 800 Hennepin Ave., and 5024-12th Ave., S., Minne apolis, Minn. HALL, Charles J. (A 1939) Htg. & Vtg. Engr. (for mail) American Radiator & Standard Sani tary Corp.. 40 W. 40th St.. New York. N. Y., and 102 Dunster Rd., Boston, Mass. HALL, Cortice H. {M 1927) Chief Engr., Stoker Div., Fairbanks, Morse & Co., and (for mail) 206 E. Hoffman St., Three Rivers, Mich. HALL, George (A 1937) Secy.-Treas. and Mgr. (for mail) Hyland, Hall & Co., 218 N. Bassett St., and 4201 Wanetah Trail, Nakoma, Madison, Wis. HALL, John R. (M 1937 ; 7 1932) Mgr., Federal Service Co., 14 W. 26th St., and (for mail) 1416 Lakeview Ave., Minneapolis, Minn. HALL, Mora S. {M 1934) Development & Sales Engr., Freed Heater & Mfg. Co.,-Collegeville, and (for mail) Rahns, Pa. HALL, Norman H. (A 1939) Supvr. House Htg. (for mail) East Ohio Gas Co., E. 62nd St. North of St. Clair, Cleveland, and 147 Beachview, Willobee, O. . HALL. Robert A. (7 1939) So. Calif. Repr. (for mail) Illinois Engineering Co., 832 W. 5th St., and 1017 S. Elden Ave., Los Angeles, Calif. HALL, Wilton L. {M 1938) Engr., Frank A. Leon Co., 901 Girard St., N. E., and (for mail) 5316 Dorsett Place, N. W.. Washington, D. C. HALLER, Arthur L. {M 1920) Pres, (for mail) Haller Appliance Sales Co., Inc., 2007 Olive St., St. Louis, and 124 W. Cedar Ave., Webster Groves, Mo. 31 HEATING VENTItATING AIR CONDITIONING GUIDE 1940 HAMACHER, K. F. (Af 1938) Partner (for mail) Hamacher & Williams, 2540 W. Wells St., and 4387 S. Austin St., Milwaukee, Wis. HAMAKER, Ambrose C. (A 1937) Sales Engr., ' Mayflower-Lewis Corp., 63 W. Milwaukee Ave., and (for mail) 18624 Santa Rosa Drive, Detroit, Mich. HAMERSKI, Francis D. (A 1940; 7 1934) Winona Coal Co., Winona, Minn. HAMIG, Louis L. (A 1940; 7 1935) Engr., John D. Falvey, Cons. Engr., 316 N. 8tb St., and (for mail) 3514 Utah St., St. Louis. Mo. HAMILTON, Lloyd L. (J 1938) Branch Office Mgr., Minneapolis-Honeywell Regulator Co., and (for mail) 208 Norwood Ave., N. E., Atlanta, Ga. HAMLET, Francis A. (A 1936) Branch Mgr. (for mail) C. A. Dunham Co., Ltd., Dominion Square Bldg., 1010 SL Catherine St., W.. and 3550 Shuter SL, Montreal, P, Q.. Canada. HAMLET, Thomas F. (Af 1938) Sales Engr. (for mail) Taylor Forbes, Ltd., 1197 University St., Montreal, and 34 Burton Ave., Westmount, P. Q., Canada. HAMLIN, James B., Jr. (A 1937) Htg. Engr., Crane Co., 14 W. Broad St., and (for mail) 1530 East 51st St., Savannah, Ga. HAMPLE, Henry (5 1939) Student, Carnegie Inst, of Technology, 4921 Forbes St.. Pittsburgh, Pa. HANBURGER. Fred W. (Af 1930) Consulting Engr., 252 West 76th St., New York, N. Y. HANLEIN, Joseph H. (Af 1937) Vice-Pres. & Treas. (for mail) Wilberding Co., Inc., S08-17th St., N. W., Room 13, and 5420 Connecticut Ave., Washington, D. C. HANLEY, Edward V. (A 1933) Pres, (for mail) & V. Hanley Co., 1653 N. Farwell Ave.. Milwau kee, and 844 E. Birch Ave., Whiteflsh Bay, Wia. HANLEY, Thomas F., Jt. (M 1933) Pres, (for mail) Hanley & Co., 1503 S. Michigan Ave., and 1640 E. 50th St.. Chicago, 111. HANSLER, John E. (Af 1937) Regional Service Engr., Delco Appliance Div., General Motors, Rochester, N. Y,, and (for mail) 104 Nelson FI., Westfield, N. J. HANSON* Leon c. (A 1918) Htg. & Plbg. Con tractor, Biorkman Bros. Co. (for mail) 712-10th St., S., and 4713 Townes Rd., Minneapolis, Minn. HANSON, Leslie P. (Af 1937: A 1936; 7 1935; S 1933) Engr., U. S. Air Conditioning Corn., 2101 Kennedy, N. E., and (for mail) 5027 Nokomis Ave, S., , Minneapolis, Minn. HANTHORN, Walter (7 1939) Engr. (for mail) Kleenair Furnace Co.. 5329 N. E. Sandy Blvd., and 2946 N. E. 54th Ave., Portland, Ore HARDAUGH, Jacob W. (Af 1937) Supt. of Erection, Kupferle-Hicks Heating Co., 3974 Del- mar Blvd., St. Louis, and (for mail) 607 Lilac St., Webster Groves, Mo. HARBERGER, G. L. (A 1939) Mgr. Peerless Htg. Div. (for mail) The Eastern Foundry Co., Boyertown, and 855 N. Evans, Pottstown, Pa. HARBORDT, Otto E. (A 1936) Sales Mgr. (for mail) U, S. Supply Co., 1315 West 12th SL, and 303 Brush Creek Blvd., Kansas City, Mo. HARD, Amos L. (A 1938) Chief Engr., Thos. Emery & Sons Co., Carew Tower, and (for mail) 910 Kreis Lane, Cincinnati, O. HARDEN, J. Clinton (Af 1938) 106 Courtland St., Dowagiac, Mich. ' HARDING, Edward R. (Af 1936) N. C. State Sales Engr. (for mail) Kewanee Boiler Corp., HARRIGAN, Edward M. (Af 1915) Gen. Mgr. (for mail) Harrigan & Reid Co., 1365 .Bagley Ave., and 7450 LaSalle Blvd., Detroit, Mich. HARRIGAN. Edward R. (Af 1939; 7 1930) Vice-Pres. (for mail) Harrigan & Reid Co., 1365 Bagley Ave., and 18688 Pennington Drive. ' Detroit, Mich. . HARRINGTON, Charles (Af 1923) 43 Indian Grove. Toronto, OnL. Canada. HARRINGTON, Elliott* (Af 1932; A 1930) Sales Mgr., Product Sales Div., Air Cond. .& Com mercial Refrigeration Dept. (for . mail) General Electric Co., 5 Lawrence St., Bloomfield, and 17 Wilson Terrace, West Caldwell, N. J. HARRIS, Albert M. (M 1938) Sales Mgr.,. Air Cond. (for mall) Baker Ice Machine Co., 509 E. 3rd St., and 2941 Glen Garden Drive, Fort Worth, Tex. HARRIS, Jesse B. (Af 1918) Co-Partner (for mail) Rose & Harris Engineers, 416 Essex Bldg., and. 3620 Colfax Ave., S., Minneapolis, Minn. HARRISON, George G. (Af 1937) Chief Engr., S. T. Johnson Co., 940 Arlington Ave., Oakland, and (for mail) 2933 Benvenue Ave., Berkeley, Calif. HARROWER, William C. (A 1937) Air Cond. Engr., Gar Wood Industries. 409 Connecticut Ave., and (for mail) 12561 Third Ave., Highland Park. Mich. ' HARSCH, Richard J. (Af 1936) Naval Archt.. U. S. Government, Navy Yard, and (for mail) , 142 Avenue O, Brooklyn, N. Y. ., ' HART, F. Donald (7 1937) Enjr. (for mail) E. I. DuPont de Nemours & Co., Inc., and 623 Delaware Ave.. Wilmington, Del. HART, Harry M.* (Af 1912) {Presidential Member) (Pres., 1916; 1st Yice-Pres., 1915; Council. 1914 1917) Pres, (for mail) L. H. Prentice Co., 1048 Van Buren St., and 3730 Lakeshore Drive, Chicago, IU. * HART. Stanley (Af 1938) Vice-Pres. (for mail) Tuttle & Bailey, Inc., and New Britain, Conn. HART, Theodore S. (Af 1938) Engr., Tuttle & Bailey, Inc., New Britain, Conn. HART-BAKER, Henry W. (Af 1918) Prop, (for mail) Hart Engineering Co., 392 E. Seward Rd.. and P. O. Box 1464. Shanghai, China. . HARTIN, William R., Jr. (7 1935) Htg. Engr.. Vice-Pres.-Secy, (for mail) W. R. Hartin & Son. Inc., 2123 Green St., and 212 S. Saluda Ave., Columbia, S. C. HARTMAN, John M. (Af 1927) Engr. (for mail) Kewanee Boiler Corp., and 618 Elliott St.. Kewanee, 111. HARTON, A. J. (A 1935) Sales Engr., St. Joseph Railway, Light, Heat & Power Co., 601 Frauds, and (for mail) 730 E. Hyde Park Ave., St. Joseph, Mo. '. HARTSOOK, Granville S., Jr. (A 1939) Mgr. (for mail) Miller & Anderson. Front Royal, Va. HARTWEIN, Charles E; (Af 1933) Supervisor, House Htg. Dept., St. Louis County Gas Co., 231 W. Lockwood, Webster Groves, and (for mail) 135 Peeke Ave., Kirkwood, Mo. HARTWELL, Joseph C. (Af 1922) Pres, (for mail) Hartwell Co., Inc., 87 Weybosset St., and 16 Freeman Parkway, Providence, R. I. HARVEY, Alexander D. (A 1928; J 1925) Sales Mgr., Bldg, insulation Div. for mail) Kimberly- Clark Corp., 8 S. Michigan Ave., Chicago, 111., and New Canaan, Conn. HARVEY, Lyle C. (Af 1928) Pres, (for mail) The Bryant Heater Co., 17825 St. Cl >ir Ave., Cleve land. and 2666 Leigh on Rd., Shaker Heights, O., P. O. Box 536, 704 Jefferson Bldg., Greensboro, HASHAGEN; John B. (Af 1930) Plant Engr. (for and Guildford College, N. C. mail) General Seafoods Corp.. 1-15 Fish Pier, HARDING, Louis A.* (Af 1911) {Presidential Boston, and 12 Park Ave., Cambridge, Mass. Member) (Pres., 1930; 1st Vice-Pres.. 1929; 2nd HATEAU, William M. (A 1939; J 1934) Drafts Vice-Pres., 1928; Council, 1922-1931) Commis man & Designer. J. O. Ross Engineering Corp., : sioner of Public Works, City Hall, and (for mail) 350 Madison Ave.. and (for mail) 1530 Sheridan -' 85 Cleveland Ave., Buffalo, N. Y. Ave., New Y.rk, N. Y. ' HARDY, Frank L. (7 1937) Secy, (for mail) Gulf-York Co., 2300-3rd Ave., N., and 2619 Arlington Ave., S., Birmingham, Ala. HARMONAY, William L. {A 1935) Treas. (for mail) M. J. Harmonay, Inc., 124 Elm St., and ' 34 Alida St., Yonkers, N. Y. HATHAWAY, Carl B. (A 1938) Salesman (for mail) Advance Insulating Co., 714 Magee Bldg., and 5204 Woodlawn Place, Pittsburgh, Pa. HATTIS, Robert E. (Af 1926) Consulting Engr. (for mail) 820 N. Michigan Ave., and 1454 W. Fargo Ave.. Chicago. 111. . 32 ROLL OF MEMBERSHIP HAUAN, Merlin J. (Af 1933) Consulting Engr.. 3412-16th S., Seattle, Wash. HAUCK, Elden L. (A 1940; 7 1936) Mgr. (for mail) Hauck Bros., 232 S. Center St., Springfield, and 1010 S. Main St., Dayton, O. HAUER, Fred (A 1937) Pies. (for mail) Fred Hauer & Co., Inc., Ill North Water St., and 315 Hettinger Place, Peoria, 111. HAUPT, Howard F. (A 1938) Htg. Salesman, Kohler Co.. 751 N. Jefferson SL, and (for mail) 614 E. Beaumont Ave., Milwaukee, Wis. HAUS, Irvin J. (A 1937; 7 1935) Engr., Everett Smith Automatic Temperatures, Inc., 789 N. Water St., and (for mail) Jackson Hotel, 926 N. Jackson St., Milwaukee, Wis. HAUSMAN, Louis M. (M 1935) Pres., L. M. Hauaman & Co., 440 Dasmarinas, and (for mail) P. O. Box 1729, Manila. P. I. HAUSS, Charles F.* {Life Member\ M 1922) Via Gesu, No. 8, Milan, Italy. HAWISHER, Harold H. (A 1938) Mech. Engr.. Automatic Heating and Engineering Co.. 418 N. Main St., and (for mail) 411 S. Jamison Ave., Lima, O. HAWK, Joseph K. (Af 1939; J 1936) Engr. & Mgr. (for mail) General Air Conditioning Co., 3096 Main SL, and 150 Byron, Buffalo, N. Y. HAWKINSON, C. F. (A 1939: 7 1936) Mech. Engr., U. S. Air Conditioning Corp., 2101 N. E. Kennedy, and (for mail) 4452-17th Ave., S.. Minneapolis. Minn. HAYES, James J. (Af 1920) Secy, (for mail) Stannard Power Equipment Co., 53 w. Jackson Blvd., and 7443 Jeffrey Ave., Chicago, IU. HAYES, Joseph G. {Life Member; M 1908) Pres.- Engr. (for mail) Hayes Brothers, Inc., 236 West Vermont St., and 2849 N. Capital Ave., Indi- . anapolis, Ind. - HAYMAN, A. Eugene, Jr. (7 1935; 5 1930) Draftsman, Moody & Hutchison, Cons. Engrs., 1701 Architects Bldg., Philadelphia, Pa., and (for mail) 2715 Washington SL, Wilmington, Del. HEDEEN, Laurel E. (7 1938) Sales Engr., The Trane Co. (for mail) 818 Hubbell Bldg., and 2823 Arnold Rd., Des Moines, la. HEDGES, H. Berkley (Af 1919) Mgr., Industrial Sales (for mail) John J. Nesbitt, Inc., State Rd. & Rhawn Sts., Holmesburg, Philadelphia, and 114 Waverly Rd., Wyncote, Pa. HEDLEY, Park S. (Af 1923) Park S. Hedley Co., 361 Delaware Ave., Buffalo, N. Y. HEDLUND, Richard A. (7 1938; 5 1937) Sales Engr. (for mail) The Trane Co., 1513 N. Cam eron, and 906 N. Third, Harrisburg, Pa. HEEBNER, Walter M. (Af 1922) Sales Engr.. Warren Webster & Co., 20 Washington Place, Newark, and (for mail) 282 Highwood Ave., Teaneck, N. J. HE1BEL, Walter E. (Af 1917) Dist. Mgr. (for mail) Aerofin Corp., 11 West 42nd St., New York; N. Y.. and Old Greenwich, Conn. HEIKKILA. Frank E. (A 1939) Salesman. Westinghouse Electric & Mfg. Co., 814 EUicott Sq., Buffalo, and (for mail) 266 Westgate Rd., Kenmore, N. Y. HEILMAN, Russell H.* (Af 1923) Senior In dustrial Fellow (for mail) Mellon Institute, 4400 Fifth Ave., and 2303 Beechwood Blvd., Pitts burgh, Pa. HEINKEL, Charles E. (7 1938) Sales Engr., Control Equipment Co.,' 304 Selling Bldg., and (for mail) 2221 N. E. Broadway, Portland, Ore. HEISTERKAMP, Herbert W. (A 1940; 7 1937) Sales Engr., The Bryant Heater Co., 17825 St. Clair Ave., and (for mail) 18103 E. Park Dr., Cleveland, O. HELBURN, I. B. (Af 1929; 7 1927) Jr. Assoc, (for mail) Wyman Engineering, 1306 Chamber of Commerce Bldg., and 3815 Winding Way. Cincinnati, O. HELLER, Joseph A. (A 1938) Sales (for mail) Air Conditioning Utilities Co., 8 West 40th SL, and 150 West 82nd SL, New York, N. Y. HELLMERS, Charles C., Jr. (7 1937) Gas Htg. HAYNES, Charles V. {Life Member; M 1917) (Presidential Member){Pres., 1934; 1st Vice-Pres., 1933; 2nd Vice-Pres., 1932: Council, 1926-1929; Engr., Iowa-Nebraska Light & Power Co., 1401 O SL. and (for mail) 2554 Woodsdale Blvd., Lincoln. Nebr. 1932-1935) Vice-Pres., Hoffman Specialty Co., Inc., 500 Fifth Ave., New York. N. Y., and HELLSTROM, John (A 1929) Vice-Pres. (for mail) American Air Filter Co., Inc., 215 Central Waterbury, Conn., and (for mail) 115 Llanfair Rd., Ardmore, Mont. Co., Pa. Ave., and 423 Lightfoot Rd., Louisville, Ky. HELMRICH, G. Bernard (Af 1936) Mech. Engr... HAYS, Charts A. (A 1937) 4868 N. Woodbum. Detroit Edison Co., 2000 Second Ave., Room 506, St., Milwaukee, Wis. Detroit, and (for mail) 26950 Dundee Rd., HAZLEHURST, Hamilton D. (A 1939) Service Huntington Woods, Royal Oak. Mich. man, Southern California Gas Co., 725 Channing HELSTROM, Clifford W. (Af 1938) Mgr., Htg. St., and (for mail) 5327 Hawley Ave., Los Plbg. & Air Cond. Dept., Globe Machinery and Angeles, Calif. . ` Supply Co., 205-11 Court Ave., and (for mail); HAZLETT. Dr. T. Lyle (Af 1938) Medical Dir. (for mail) Westigghouse Electric & Mfg. Co., 3509 Fifth Ave., and 6634 Beacon SL, Pittsburgh, Pa. HEARD, John A. E. (A 1938; 7 1930) Carrier Air Conditioning Co., Ltd., 24 Buckingham Gate, London, S..W. 1, England. HEATH, William R. (Af 1931) Asst. Chief Engr.. Buffalo Forge Co., 490 Broadway, and (for mail) 119 Wingate Ave., Buffalo, N. Y. 1614 Thompson Ave., Des Moines. Ia. HELSTROM, Herman G. (Af 1928) Fire-box Boilers and Stoker Div. (for mail) Wm. Bros. Boiler and Mfg. Co., Nicollet Island, and 4608 Arden Ave., S., Minneapolis, Minn. HENDERSON, Alexander S. (7 1940; S 1938) Engr. Draftsman (for mail) Carrier Air Con ditioning. Ltd., 36-40 Bourke St., Sydney, N. S. W., and 500 Blaxland Rd., Eastwood, 14 S Australia HENDRICKSON, Harold M. (Af 1933) Asst. HEBERLING, C. W. (A 1934) Box 115, Wayzata, Minn. Branch Engr. (for mail) York Ice Machinery Corp., 5051 Santa Fe Ave., Los Angeles, and HEBLEY, Henry F. (Af 1934) Prod. Control Mgr., 3901 Liberty Blvd., South Gate, Calif. Pittsburgh Coal Co., P. O. Box 146, Pittsburgh, HENDRICKSON, Ralph L. (Af 1938) Chief Engr., Pa. Utilities Engineering InsL, 404 N. Wells SL, HECHT. Frank H. (Af 1930) Sales Engr. (for Chicago, III. ' mail) B. F. Sturtevant Co., 2635 Koppere Bldg., HENDRIKSEN, Leonard (A 1938) Prop., Hen- and 1467 Bamesdale St., Pittsburgh, Pa. driksen Sheet Metal & Heating Service, 1919 HECKEL, Edmund P. (Af 1918) Consulting & Mechanical Engr., E. P. Heckel & Associates, 407 S. Dearborn St., Chicago, and (for mail) 314 Cuttriss Place, Park Ridge, 111. HECKLER, Samuel (7 1937) Engr. (for mail) Westchester Square Plumbing Supply Co., Inc., 4617 White Plains Ave., and 2800 Creston Ave., New York, N, Y. HEDDEN. Willard M. (A 1937) Treas., The Hedden Co. (for mail) 17-25 S. Warren St., and 7 Reservoir Ave., Dover, N. J. Vernon Ave., Flint, Mich. - HENION, Hudson D. (A 1923) Sales Mgr. (for mail) C. A. Dunham Co., Ltd., 1523 Davenport Rd., and 45 Ridge Drive, Toronto, OnL, Canada. HENNESSY, William J. (Af 1937) Personnel Dir., Green Foundry & Furnace Works, 3rd & Elm SL, and (for mail) 1238-47th St., Des Moines, la. HENRY, Alexander S., Jr. (Af 1930) 300 Central Park West, New York, N. Y. HENRY, Ernest C. (Af 1938) Mgr., E. C. Henry Co.. 101 Salzburg Ave., and (for mail) 1115 Park Ave., Bay City. Mich. 33 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 HENSZEY, William P. (A 1940; J 1935) 320 ' Hamilton Ave., State College, Pa. HERBACEK, Edward E. (Af 1938) Chief Engr. & HILL, Charles F. (J 1936) Mgr., Carrier Air Cond. Dept., United Engineers, Ltd., River Valley Rd., Singapore, Straits Settlements. Secy., Spencer Air Conditioning Co., 2936 Pilla* HILL, Edward, Jr. (J 1939) Designing Engr., bury Ave.. and (for mail) 4624 Upton Ave., S,, Warm Air Div., American Radiator & Standard Minneapolis, Minn. . HERBERT, Richard M. (J 1938) Herbert Re Sanitary Corp., 4th & Townesend, and (for mail) 3355 Octavia St., San Francisco, Calif; frigeration, 917 E. 4th St., Waterloo, la. HILL, Dr. E. Vernon* (Af 1914; A 1912) (Presi- HERING, Alfred (Af 1935) Pres., Hering Heating denlial Member) (Pres., 1920; 1st Vice-Pres., Co., Inc., 1465 Third Ave., and (for mail) 1830 1919; 2nd Vice-Pres., 1918; Council..1915-1921) Tenbroeck Ave., New York. N. Y. Owner (for mail) 179 W. Washington St., and HERKIMER, Herbert (Af 1934) Dir. (for mail) 6826 Newell Ave., Chicago, 111. Herkimer Institute. 1819 Broadway, and 25 HILL, Fred M. (Af 1930) Engr., Plbg.. Htg. & Central Park West, New York, N. Y. Vtg.. 2104 S. Vermont Ave., and (for mail) 225 HERLIHY, Jeremiah J. {Life Member; M 1914) East Avenue 39, Los Angeles. Calif. 3751 Eddy St., Chicago. 111. HERMAN, Nell B. (J 1937; 5 1936) Engr. (for HILL, Harold G. (J 1938) Sales Engr.. Gurney Foundry Co., Ltd., Junction Rd., and (for mail) mail) Riggs Distler & Co., Inc., 713 Maritime 91 Glendonwynne Rd., Toronto, Ont., Canada. Bldg., New Orleans. La., and 4217 Garfield Ave., HILL, Harold H. (Af 1935) Branch Mgr. (for mail) S,, Minneapolis, Minn. HERRING, Edgar (Life Member; Af 1919) Chair American Blower Corp., 1211 Commercial Bank Bldg., and 2303 Vail Ave., Charlotte, N. C. man and Governing Dir. (for mail) J. Jeffreys & HILL Jared A. (Af 1937) Htg. & Air Cond. Engr., Co., St. George's House, 195-203, Waterloo Rd., Pacific Gas & Electric Co., 245 Market St., San London, S. E. I, and "Kenia," Keswick Rd., Francisco, and (for mial) 717 Laurel Ave,, i!i Putney, London, S. W., England. HERSH, Franklin C. (M 1939: A 1933; J 1930) Specialty Engr. (Htg., Vtg. & Air Cond.) Pennsyl Burlingame, Calif. HILL, Vaughn H. (J 1938) Mgr. Htg. Dept, (for mail) Hager & Cove Lumber Co., 1125 S. Penn vania Power & Light Co., 901 Hamilton St., and Ave.. and Rte. 2, Lansing, Mich. - (for mail) 47 S. St. Cloud St., Allentown, Pa. HERSKE, Arthur R. (M 1926) Pres., Herske & HILLEGER. Marvin L. (J 1939) Air Cond. Engr., 1100 East 33rd St., and (for mail) 1151 W. 69th ' Timmis. Inc., 11 W. 42nd St., New York, and (for mail) 101 Brookfield Rd., Mt. Vernon, N. Y. St., Los Angeles, Calif. HILLS, Arthur H. (Af 1924) Mgr. (for mail) HERTY, Frank B. (M 1933) Rm. 3000, 51 Sarco Canada, Ltd., 85 Richmond St., W., ana Madison Ave., New York, N. Y. HERTZLER, John R.* (Af 1936; J 1928) Gen. Repr., Refrig- & Air Cond. (for mail) York Ice 100 Nealon Ave., Toronto, Ont., Canada. HINES, Guy M. (A 1937) Chief Engr., Agri cultural & Mechanical College of Texas, College Machinery Corp., and 863 S. George St., York, Pa. HESS, Arthur J. (Af 1937) Engr. (for mail) Station, Tex. HINES, John C. (Af 1937) Vice-Pres.-Treas. (for mail) R. B. Hayward Co., 1714 Sheffield Ave., English and Lauer, Inc., 1978 S. Los Angeles St., Chicago, and 6629 Ramona Ave., Lincolnwood, and 2616 West 70th St., Los Angeles, Calif. HESSELSCHWERDT, August L,, Jr. (A 1940; J 1937) Instructor, Mech. Engrg., Wayne Uni versity, 4841 Cass Ave., and (for mail) 15722 Kentucky Ave., Detroit, Mich. HESSLER, Lester W. (Af 1936) Branch Mgr., The Trane Co., 1835 N. 3rd St., and (for mail) 6034 III. HINNANT, Clarence H,, Jr. (J 1938) Chief Engr., Hungerford Coal Co., 717 E. Grace St., and (for mail) R. F. D. No. 9, Box 156, Richmond, Va. HINRICHSEN, Arthur F. (Af 1928) Pres. & Treas. (for mail) A. F. Hinrichsen, Inc., 50 Church St., New York, N. Y,, and Mountain N. Bayridge, Milwaukee, Wis. HESTER, Thomas J. (Af 1919) Vice-Pres.-Treas. (for mail) Hester Bradley Co., 2835 Washington Ave.. and 67 Aberdeen Place. St. Louis, Mo. HEWETT, John B. (Af 1937: A 1935) Anemostat Corp. of America, 10 East 39th St., New York, and (for mail) Sussex Hall, Dobbs Ferry, N. Y. I^akes J , HIRSCH, Martin H. (Af 1938) Sales Engr., Hoffman Specialty Co., Inc., 500 Fifth Ave., and (for mail) 1478 Walton Ave., New York, N. Y. HIRSCHMAN, William F. (Af 1929) Pres, and Chief Engr., W. F. Hirschman Co., Inc., 220 Delaware Ave., and (for mail) 165 Le Brun HEYDON, Charles G. (A 1923) Mgr., Sales of Western Div., Wright Austin Co., 315 West Woodbridge St., and (for mail) 2681 Nebraska Detroit, Mich. HIBBS, Frank C. (Af 1917) Htg. Engr., The H. B. Smith Co., Inc., 2209 Chestnut St., and (for mail) 846 North 65th St., Philadelphia, Pa. ` Circle. Buffalo,' N; Y. HITCHCOCK, Paul C. (Af 1931) Vice-Pres. (for mail) Burlingame, Hitchcock & Estabrook, Inc., 521 Sexton Bldg., and 5130 Harriet Ave., Minne apolis, Minn. ' HITT, John C. (A 1936) Branch Mgr. (for mail) Holland Furnace Co., 55-18th St., and Howard HICKEY, Daniel W. (A 1931) Pres., D. W. Hickey & Co.. Inc. (for mail) 1631 University Ave., St. Paul, Minn. HICKMAN, Herbert V. (A 1938) Sales Engr.. Anemostat Corp. of America, 1129 Folsom St., San Francisco, Calif. HIERS, Charles R. (Af 1929; J 1927) Sales Engr., Minneapolis-Honeywell Regulator Co., 801 Second Ave., New York, and (for mail) 19 Place, Wheeling, W. Va. '' HOBBIE, Edward H. (A 1937) Mgr. Sales Pro motion and Research (for mail) Mississippi Glass Co., 220 Fifth Ave., New York, N. Y., and Ridgedale Ave., Florham Park. N. J. HOBBS, J. Clarence (Af 1920) Vice-Pres. Dia mond Alkali Co., Painesville, O. HOBBS, William S. (A 1936) (for mail) Wm. S. Hobbs, P. O. Box 269, and 327 Park Ave., Westminster Rd., Great Neck, L. I., N .Y. Swarthmore, Pa. HIGH, John M. (A 1938) Mgr., The Ruberiod HOCHMAN, Eugene (J 1940; S 1938) Jr. Mech. Co., 500 Fifth Ave., New York, N. Y. Engr., U. S. Navy Yard, Boston, and (for mail). 286 Chestnut St., Chelsea, Mass. ' HILDER, Frederick L. (Af 1937). Chief Engr., Electric Furnace-Man, Inc., 780 E. 138th St., New York, N. Y., and (for mail) 162 Trenton HOCKENSMITH, Francis E. (Af 1936) Chief Engr. (for mail) Lennox Furnace Co., Inc., 400 Ave., Clifton, N. J. N. Midler Ave., and 124 Ludington St., Syracuse, il HILDRETH, Egbert S. (A 1936) Air Cond. Promotion (for mail) Indianapolis Power & Light Co., 17 N. Meridian SL, and 5626 E. Michigan St., Indianapolis, Ind. HILDRETH, Lane W. (Af 1935) Sales & Service Engr. (for mail) Cranberry Improvement Co., 1416 Chestnut St., and Apt. B-302, 236 W. N. Y. HODGE, William B. (Af 1934) Vice-Pres. & Engr. (for mail) Parks-Cramer Co., P. O. Box 1234, and 30l Hawthorne Lane, Charlotte, N. C. HOEHL, Edward R. (J 1935) Pres.-Mgr. (for mail) Long Island Air Conditioning Co., Inc., 544 Franklin Ave., Garden City, and 145 Terrace Walnut Lane, Philadelphia, Pa. Ave., Hempstead, L. I., N. Y. 34 ROLL OF MEMBERSHIP HOEY, James K. (A 1938) Pres.-Mgr. (Regis tered Msh. Engr.) (for mail) Crater Metal & Engineering, Inc., 142 N. Front St., and 119 Lincoln St., Medford, Ore. HOSHALL, Robert Houston (Af 1930) Associate (for mail) Thos. H. Allen, Cons. Engr., 65 McCall Place, and 1844 Cowden Ave., Memphis, Tenn. HOSKING, Homer L. (Af 1930) Mgr., Pacific Steel HOFFMAN, Charles S. (Af 1924) Pres, (for mail) Baker Smith & Co., Inc, 576 Greenwich St., Boiler Div., 101 Park Ave., New York, and 208 Madison Rd., Scarsdale, N. Y. and 108 East 38th St., New York, N. Y. HOFFMAN, Harry (Af 1939) Branch Mgr. (for HOSTERMAN, Charles O. (Af 1024) Supt., The McMurrer Co., 303 Congress St., Boston, and mail) Johnson Service Co., 105 Piedmont Bldg., (for mail) 25 Bateswell Rd., Dorchester, Mass; Greensboro, and R-l, Guilford College, N. C. HOFFMANN, Angelo (A 1938) Vice-Pres. (for mail) Louis Hoffmann Co., 117 W. Pittsburgh HOTCHKISS. Charles H. B. (Af 1927) Editor. Heating and Ventilating, 148 Lafayette St., New York, N. Y. Ave.,and4850N. Oakland Ave., Milwaukee, Wis. HOGAN, Edward L.* (Af 1911) General Con sulting Engr. (for mail) American Blower Corp., 6000 Russell St., and 700 Seward Ave., Detroit, Mich. HOGUE, William M. (A 1935) Sales Engr. (for HOTOP, Norbert C. (A 1938) Vice-Pres. and Mgr. (for mail) Fred J. Hotop & Co., 315 N. Church St., and 617 Edgemoor Ave., Kalamazoo, Mich. HOUGHTEN, Ferry C.* (M 1921) Dir. (for mail) Research Lab., A.S.H.V.E., U: S. Bureau of mail) U. S. Electrical Motors, Inc., 200 E. Mines. 4800 Forbes St., and 1136 Murrayhill Slauson Ave., and 4839 Keniston Ave., Los Angeles, Calif. ' HOLLAND, George R. (5 1938) Inspector, Abbott, Lester & Co., Inc., 140 Cedar St., and (for mail) 35-07-90th St., Jackson Heights, L. I., N. Y. HOLLAND, Robert B. (Af 1937) Sales Engr. (for mail) York Ice' Machinery Corp., 1275 Folsom St., and 3820 Scott St., San Francisco, Calif. HOLLISTER, Norman A.* (Af 1933) 7101 Colo nial Rd., Brooklyn, N. Y. HOLMES. Arthur D. (Af 1.935) Vice-Pres. (for m il) Plumbers Supply Co., 323 W. First, and 1848 East 18th St., Tulsa, Okla. Ave., Pittsburgh, Pa. HOULIS, Louis D. (Af 1935) Chief Engr., Master Baker Ovens, and (for mail) 836 Pedretti Rd., West Price Hill, Cincinnati, O. HOULISTON, G. Baillie (A 1928) Secy, (for mail) The W- C. Green Co., 704 Race St., Cincinnati, O., and 33 Tremont Ave.. Fort Thomas, Ky, HOUSKA, Arthur D. (A 1940; J 1937) Sales Engr. (for mail) Clowe & Cowan, Inc., and 1009 Monroe St., Apt.-1, Amarillo, Tex. HOWARD. Fenton L. (Af 1937) Chief Engr. (for mail) Refrigeration & Air Conditioning Inst., 2150 Lawrence Ave., and 6619 N. Rockwell St., Chicago, 111. HOLMES, Paul B. (A 1936) Branch Mgr. (for HOWATT, John* (Af 1915) (Presidential Member) mail) The National Radiator Co., 600 West St., N. E., and 4525 Fessendon St., N. W., Wash ington, D. C. HOLMES. Richard E. (A 1938; J 1934) Air Cond. (Pres., 1935; 1st Vice-Pres., 1934; 2nd Vice-Pres., , 1933; Council. 1927-1936) Chief Engr. (for mail) Board of Education, 228 N. LaSalle St., and' 4940 East End Ave., Chicago, III. Design Engr., Westinghouse Electric & Mfg. Co., HOWE, Willis W. (M 1936; A 1917) Sales Engr., 653 Page Blvd., and (for mail) 258 Redlands St., Springfield. Mass. . HOLT, James (Af 1933) Assoc. Prof, of Mech. Engrg. (for mail) Massachusetts Institute of .Technology, Cambridge, and 1062 Massachusetts Ave., Lexington, Mass. Pacific Gas & Electric Co., and (for mail) 68 Central Ave., Sausalito, Calif. HOWELL, Lloyd (Af 1915) Engr., Industrial Dept, (for mail) Peoples Gas Light and Coke Co., 122 S. Michigan Ave., and 7605 Yates Ave.; Chicago, 111. HOLT, Walter H. (J 1938) Engr. (for mail) HOYT, Charles W. (A 1931) Pres.-Treas. (for Buffalo Forge Co., 490 Broadway, and 149 Highland Ave., Buffalo, N. Y. HOLUBA, Henry J. (J 1938) Sales Engr. (for mail) mail) Wolverine Equipment Co., 31. Main St., Cambridge, and 45 Thaxter Rd., Newtonville, Mass. A-J Manufacturing Co., 2119 Washington St., and 501 W. 31st, Kansas City, Mo. HOYT, Leroy W. (Af 1930) N. Stamford Ave., Stamford, Conn. HOLYFIELD, Earl F. (A 1937) Air Cond. Engr., Oklahoma Electrical Supply, and (for mail) 121 E. Park Ave., Oklahoma City, Okla. HOMAN, John . (Af 1938) Chief Elec. Engr., Amalgamated Phosphate Co., P. O. Box 172, Brewster, Fla. . HONERKAMP, Fritz (Af 1937) Chief Engr. (for HUBBARD, George W.* (Af 1911) Consulting Engr. (for mail) 1406 Railway Exchange, Chicago, and 710 Bonnie Brae, River Forest, 111. HUBBARD, Nelson B. (Af 1919) Partner, Hub bard & Wagschal, Engineers, 243 Congress St., W., and (for mail) 2985 Blaine Ave., Detroit, Mich. . mail) Anemostat Corp. of America, 10 East 39th St., New York, and 67-12 50th Ave., Woodside, L. I.. N. Y. HOOK, Frank W. (Af 1937) Branch Mgr. (for mail) Johnson Service Co., 814 Rialto Bldg., HUBBUCH, Nicholas J., Jr. (S 1939) Student University of Dayton. Dayton, O., and (for mail) 510 Breckenridge Lane, Louisville, Ky. HUBER, Enrique (Af 1938) Mech. Engr., Calle ' Marsella Num. 66, Mexico, D. F. : 2444 Lar in St.. San Francisco, Calif. HOPPE, Albert A. (Af 1935) Design and Appli cation Engr., Carrier Corp., 213 West 1st St., and (for mail) 1941 N. W. 17th St., Oklahoma City, Okla. HUCH, A. J. (Af 1919) Sales Mgr. (for mail) American Radiator & Standard Sanitary Corp., 312 S. 3rd St., and 4037 Harriet Ave., Minne apolis, Minn. HOPPE, Marcel F. (Af 1938) Consulting Engr. HUCKER, Joseph H. (Af 1921) Partner (for mail) (for mail) 1621 Connecticut Ave., N. W.f Wash Hucker-Pryibil Co., 1700 Walnut St., Philadel ington. D. C..and P. O. Box531, Falls Church, Va. phia, and 715 Stanbridge St., Norristown, Pa. HOPPER, Garnet H. (Af 1923) Engr., Taylor- HUDEPOHL, Louis F. (Af 1936) Pres, (for mail) Forbes, Ltd., 1088 King St., W., and (for mail) 19 Brummell Ave., Toronto, Ont., Canada. T. J. Conner, Inc., 3290 Spring Grove Ave., and 4395 Haight Ave., Cincinnati, O. HOPPER, John S. (Af 1938) Instructor, Agri HUDSON, Robert A. (Af 1934) Partner (for mail) cultural & Mechanical College of Texas, Mech. Hunter & Hudson. Cons. Engrs., 41 Sutter SL, Engrg. Dept., College Station, Tex. Room 710, San Frandsco, and Route 2, Box 51, HOPSON, William T. (Life Member; Af 1915) The Cordilleras Rd., Redwood City, Calif. Hopson & Chapin Mfg. Co., New London, Conn. HORCH, George E. (Af 1939) Mech. Engr., Wm. B. Ittner, Inc., 911 Locust St., St. Louis, Mo. HORNER, S. David (J 1937) Sales Engr., Powers Regulator Co., 2720 Greenview Ave., and (for mail) 448 Barry Ave., Chicago, 111. HORNUNG, J. C. (Af 1914) 854 Bluff St.. Glencoe. III. . HUGGINS. L. Gale (Af 1939) Asst. Mgr., Air Cond. Dept., Westinghouse Electric & Mfg. Co., and (for mail) 176 Springfield St., Springfield. Mass. .' HUGHES, Harold R. (A 1938) Mgr., Fuel Oil Div. (for mail) McColl Frontenac Oil Co., Ltd., 1010 St. Catherine St., W., Montreal, and 235 St. Joseph St., Dorval, P. Q., Canada. 35 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 HUGHES, L. K. (A 1940; J 1936) Vice-Pres. in ' Charge of Sales, Howard Air Conditioning, Ltd-, 881 Yonge St., and (for mail) 43 Rivercourt Blvd., Toronto. O L, Canada. HUGHES, William U. (Af 1936) Pres, (for mail) The Lewis-Brown Co., Ltd., 1411 Crescent St., Room 206, and 1610 Sherbrooke St.. W., Apt. 36, Montreal, P. Q-. Canada. HIGHEY, Thomas M. (A 1935) Div. Sales Mgr., American Gas Machine Co.. 666 Lake Shore Drive, Chicago, 111., and (for mail) 2350 North 58th St., Milwaukee, Wis. HUGHSON, Harry H. (M 1927) Sales Engr, (for mail) The Coon-DeVisser Co., 2051 W. Lafayette St., Detroit, and 58 Florence Ave., Highland Park, Mich. HULL, Harry B. (Af 1931) Research Engr. (for mail) Frigidaire Div. of General Motors Corp., and 1454 Glendale Ave., Dayton, O. HUMMEL, George W. (Af 1937) Sales Engr. (for mail) The Trane Co., Drawer 679. and 327 E. McDowell Rd.. Phoenix, Ari?. HUMPHREY, Dwight E. (Af 1921) Htg. & Vtg. Engr., Goodyea - Tire & Rubber Co., Akron, and (for mail) 2499 Six St., Cuyahoga Falls, O. HUTZEL, Hugo F. (Af 1918) Mgr. Tech' & Training Dept., Nash Kelvinator Corp., and (for mail) 2635 Woodstock Dr., Detroit, Mich. HUYBERT, Leslie E., Jr. (J 1938) Draftsman U. S. Naval Operating Base, and (for mail) 604 Carolina Ave., Norfolk, Va. HVOSLEF, Frederick W- (M 3931; A 1921) Heating Research Engr. (for mail) Kohler Co., and 523 Audubon Rd., Kohler, Wis. . HYDE, Elmer H. (A 1937) Tech. Repr.. Koppers Co., Tar & Chemical Div., 501 Flannery Bldg., and (for mail) 442SulgraveRd., Pittsburgh (ll)Pa. HYDE, Eric F. (M 1937) Mech. Engr., GiBels & Vallet, Inc-. 1000 Marquette Bldg., Detroit, and (for mail) 708 Oakland Ave., Birmingham, Mich. HYDE, E. V. (/1939) Sales, Wood Conversion Co., 810 Stephenson Bldg., and (for mail) 5567 Somerset. Detroit, Mich. HYMAN, Wallace M. (Af 1920) Pres- (for mail) Reis & O'Donovan, Inc., 12 W. 21st St., and 23 W. 73rd St., New York. N. Y. HYNES, Lee P. (M 1919) Pres, and Chief Engr; (for mail) Hynes Electric Heating Co.. 240 Cherry St., Philadelphia, Pa., and 127 West End Ave., Haddonfield. N. J. HUMPHREY, Leonard G., Jr. (J 1938) Sales Engr. (for mail) Buffalo Forge Co., 640 Wood I ward Bldg., Washington, D. C., and 4702 IB1SON, James L. (J 1938) Sales Engr. (for mail) Highland Ave.. Bethesda, Md. HUMPHREYS, Clark M. (Af 1931) (Council, 1936-1938) Asst. Prof, of Mech. Engrg. (for mail) American Blower Corp., 632 Fisher Bldg., and 896 Pallisier Ave., Detroit, Mich. ICKERlNGILL, John C. (Af 1923) Sales Engr., Carnegie Institute of Technology, Schenley Park, Spencer Heater Co., 2020 N. Broad St., and (for and 1934 Remington Dr., Pittsburgh, Pa. HUNGER, Robert F. (Af 1927) Associate Dist. Mgr. (for mail) Davidson & Hunger, 220 South mail) 477 Flamingo St., Roxborough, Phila delphia, Pa. ILLIG. Ernest E. (J 1938) Sales Engr., Walter 16th St., Philadelphia, and 100 Avon Rd., Nar-. R. Illig, 1 Cushing St., and (for mail) 242 Blossom berth. Pa. HVNGERFORD, Leo CM 1930) Sales Mgr.. St., Fitchburg, Mass. ILLIG. Walter R. (Af 1935; A 1927) Owner. Utility Fan Corp., 2528 Santa Fe Ave., and (for mail) 828 N. Stanley Ave.. Los Angeles. Calif. Heating. Plumbing. Air Conditioning. 1 Cushing St., and (for mail) 242 Blossom SL. Fitchburg, HUNT, MacDonald (A 1936) Mfrs. Agent (for mail) McDonnell & Miller, 12 W. Madison St,, Mass. INGALLS, Frederick D. B. (Af 1900) Consulting and Windsor Court Apts., Baltimore, Md. Htg. and Air Cond. Engr., 1 Hopkins St., HUNT, Noel P. (Af 1034) Managing Director (for mail) Carrier Australasia, Ltd., 41-49 Forbes Reading, Mass. INGELS. Margaret* (Af 1923; J 1918) Mech. St., and 52 Lang Rd., Centennial Park. Sydney, Engr. (for mail) Carrier Corp., and 412 University N. S. W., Australia. HUNTER, Louis N. (Af 1936) Mgr. of Research Place, Syracuse, N. Y. '' IRWIN, Robert R. {J 1937) Air Cond. Engr. (for (for mail) The National Radiator Co.. 221 Central mail) York Ice Machinery Corp,, Mayo Building, Ave., and 839 Luzerne St., Johnstown. Pa. and 811 North Rockford SL, Tulsa, Okla. HUNZIKER, Chester E. (A 1934) Dist. Mgr. ISAACS, Harry A., Jr. (A 1939) Pres, (for mail) (for mail) American Blower Corp., 511 State St., OH Delivery, Inc, 105 Monmouth St.. Red Bank, Schenectady, and 422 Reynolds St., Scotia, N. Y. HURWICH, Sidney B. (A 1939) Engr. (for mail) and Little Silver, N. J. 1 1SETT, William M. (A 1936) Pres- (for. mail) American Lubricants, Inc., 1575 Clinton St., C. B. Isett & Son, Inc.. 3035 N. Rockwell St., and 177 Wyoming Ave-, Buffalo, N. Y. and 4236 N. Drake Ave., Chicago, ID. - HUST. Carl E, (A/ 1932) Supervisor Heating Engr. dTSSERTELLE, Henry G.* (Life Member; Af (for mail) Cincinnati Gas & Electric Co., 4th & 1913; A 1912) Consulting Engineer, 3i Park Main Sts., and 15 Mason St., Cincinnati, O. HUSTOEL. Arnold M. (A 1930) 2414 N. Kedzie Terrace W.. Apt. A-S, New York. N. Y. IVERSON, Henry R. (Af 1936) Co-Mgr. (for mail) Blvd.. Chicago, 111. The Trane Co., 1772 Columbia Rd., N. W., and HUTCHEON, Clifford R. (J 1938) Engr. (for T601 Argonne Place, N. W., Washington, D. C. mail) Anemostat Corp. of America, 10 E. 39th IVERSTROM, Carl (A 1940; J 1939) Job Engr., St., New York, and 144-03 Barclay Ave., W. P. A., 260 E. 161st St., and (for mail) 165 Flushing, L. L, N. Y. Seaman Ave.. New York, N. Y. HUTCHINGS, Robert L. (J 1937) Hughes Heating & Air Conditioning Co., 125 N. Jefferson j St.. Dayton. O. HUTCHINS, William H- CM 1934) Works Mgr., Delco Appliance Div., General Motors Corp., 391 Lyell Ave.. aod (for mail) 88 Magee St., JACKES. Herman D. (Af 1915) Consulting Engr., 185 Liberty St., Bloomfield, N. J. . JACKSON, Charles H. (Af 1923) Vice-Pres. (for mail) Blower Application Co., 918 N. Fourth St., Rochester. N. Y. and 2706 N. FarweU Ave., Milwaukee, Wis. HUTCHINSON, B. Lee, Jr. (J J939) Engr. (lor JACKSON, Gilbert R. (Af 1938) Mgr,, Boffer & mail) York Ice Machinery Corp., 659 E. Sixth Radiator Dept, (for mail) Crane, Ltd., 45-51 St., and 1945 Madison Rd., Cincinnati, O. HUTCHINSON, Frank W. (a 1937) 114 Engi neering Bldg., University of California, .Berkeley, Leman St., London, E. 1, England. JACKSON, Marshal! S. (M1919) Repr. (fox'mail) Powers Regulator Co., 250 Delaware Ave., and Calif. HUTCHINSON, Frederick A. {J 1939) Mgr.. Repair Dept., C.J. Doughty& Co., 30 Brenan Rd., and (for mail) 31 Lucerne Rd., Shanghai, China. HUTCHISON, John E. (Af 1921) Partner (for mail) Moody & Hutchison, Cons. Engrs.. 1701 Architects Bldg., and 5129 Newhall St., Phila delphia, Pa. 108 Larchmont Rd., Buffalo, N. Y. ` JACKSON, Walter F. (/ 1939) Lab. Engr. (for mail) American Stove Co., 1200 Long Ave., Lorain, and 209 Cascade St.. Elyria* O. JACOBI. Bruce A. (J 1939; S 1936) Mgr., Fan & Blower Div., Air Conditioning Utilities, 8 W. 40th St., New York, and (for mail) 1731 E. 17th St., Brooklyn, N. Y. 36 ROLL OF MEMBERSHIP JACOBSEN, K, G. S. (A 1939) Sales Repr., Imperial Electric Co., and (for mail) 309 South 22nd SL, Philadelphia, Fa. JACOBUS, Dr. David S. (Life Member; M 1916) Advisory Engr- (for mad) The Babcock & Wilcox Co., 85 Liberty St,, New York, N. Y., and 93 Harrison Ave., Montclair, N. J. JAKOBY, Albert C. (A 1938) Estimator and De signer, Sears Roebuck & Co., 4640 Roosevelt Blvd., and (for mail) 1913 E. Clearfield SL. Philadelphia, Pa, JALONACK, Irwin G. (A 1933; 5 1930) Chief Engr. (for mail) Alfred L. Hart, Inc., 164-07 Hillside Ave., Jamaica, and 60-47 Saunders SL, Rego Park. L. I.. N. Y. . JAMES, Hamilton R. (Af 1931) Service Equip. Engr., United Engineers & Constructors. Inc., 1401 Arch SL, Philadelphia, and (for mail) 55 W. Drexel Ave., Laosdowne, Pa. JAMES, John W.* (Af 1937; J 1933) Tech. Secy.. American Society of Heating & Ventilating Engineers, 51 Madison Ave., New York, N. Y. JAMES, Richard E. CM 1936) Mgr., Htg. Dept., Harry Cooper Supply Co., and (for mail) 597 E. Elm St., Springfield, Mo. JANET, Harry L. (Af 1920) Mech. Engr., Buensod- Stacey Air Conditioning, Inc., 60 East 42nd St., New York, and (for mail) 688 Decatur St., Brooklyn, N. V. JARCHO. Martin D. (A 1939; J 1936) Vice-Pres. (for mail) Jarcho Bros., Inc., 304 East 45th St.. New York, and 941 Washington Ave., Brooklyn, N. Y. JARDINE, Douglas C. (Af 1929; A 1926) Pres, (for mail) Jardine & Knight Plumbing & Heating Co., 516 S. Tejon SL, and 1612 E. Platte Ave., Colorado Springs, Colo. JARDINE, William H., Jr. (A 1938) Pres- (for mail) Iona Ventilator Co., Inc., 2821-29 W. Dauphin SL. and 3552 SheJmire St., Philadelphia. Pa. JEHLE, Ferdinand (Af 1938; A 1937) Dir. of Research (for mail) Hoffman Specialty Co., Inc,, 575 Pacific St., Stamford, and 7 Colonial Court, New Canaan, Conn. JELINEK, Frank R. (J 1937) Branch Mgr. (for mail) Johnson Service Co., 2505 Commerce SL. and Clifton Hotel, Dallas, Tex. JOHNS, Harold B.* (Af 1928; J 1927) (for mail) Peoples Gas Light & Coke Co., 122 S. Michigan Ave., Chicago, and 543 N. Elmwood Ave., Oak Park. 111. JOHNSON. Allen J * (M 1935) Dir. (for mail) Anthracite Industries Laboratory. Primos, Dela ware Co., and 344 Congress Ave.. Lansdowne, Pa. JOHNSON. Carl E. <A 1939; J 1930) Pres, (for mail) Sunbeam Htg. & Air Cond. Co., 346 Peach tree SL, N. E,, and 1154 Ridgewood Dr.. N. E., Atlanta, Ga. JOHNSON, Carl W. (Af 1912) Pres., C. W. Johnson, Inc., 211 N. Desplaines St., Chicago. III. JOHNSON, Clarence W. (M 1933; J 1931) Dist. Mgr. (for mail) Canadian Sirocco Co., Ltd., 630 Dorchester St., W., and 130 Graham Blvd., Mt. Royal, Montreal. P. Q., Canada. JOHNSON, Edward B. (Af 1919) Sales Engr., Staten Island Supply Co., Inc., 1390 Richmond Terrace, and (for mail) 154 Wardwell Ave., West New Brighton, S. I., N. Y. JOHNSON, Fred W, CM 1916) Vice-Pres. (for mail) Johnson Larsen & Co.. 6530 Beaub:en SL, Detroit, and AdamsRd.,R. F. D.No.2, Birming ham, Mich. ,' JOHNSON, Helge S. (A 1933; / 1927) Dist. Mgr. (for mail) Buffalo Forge Co.. 1305 Standard Bldg., and 20 Fleetwood Ave., Albany, N. Y. JOHNSON, Leslie O. (Af 1938: J 1930) Sales Engr., H. Y. Keeler Co., 910 Hines Bldg., and (for mail) 2520 First Ave., Huntington, W. Va. JOHNSON, Oliver W. CM 1937) Chemical Engr.. Standard OU Co. of Calif., 225 Bush SL, San Francisco, and (for mail) 1831 Waveily St., Palo Alto, Calif. JOHNSON, Robert F. (J 1938) Salef Engr. (for mail) Howard . Melton, Inc., 207 N. w. 10th St.. Oklahoma City, Okla. JOHNSON, Tracy R. (Af 1924) Branch Mgr. (for mail) The Trane Co., Hubbdl Bldg., and 3438 University Ave., Des Moines, la. JOHNSTON, J. Ambler (Af 1912) Partner (for mail) Carneal, Johnston & Wright, 1000 Atlantic Life Bldg., and 2616 Hanover Ave., Richmond. Va. JOHNSTON, Marriott T. (Af 1939) Engr., Bankers Life Co.. Seventh & High Sts., and (for mail) 1641-38th St., Des Moines; la. JENKINS, Frank H, (J 1939; S 1938) Student JOHNSTON, Robert E. (M 1929; A 1926) Pres, Engr. (for mail) Buffalo Forge Co., 490 Broad (for mail) R. E. Johnston Co., Ltd., 1070 Homer way. and 301 Woodward Ave., Buffalo, N. Y. JENNEY, Hugh B. (A 1938) General Sates Mgr. (for mail) Dominion Radiator and Boiler Co., Ltd., Cor. Royce an ' Lansdowne Avea., and 96 Dawlish Ave., Toronto, Ont., Canada. ' JENNINGS. Hal K. (Af 1937) DisL Mgr., Avery Engineering Co.. 1023 Chamber of Commerce Bldg., and (for mall) 3748 Middle Brook Ave., Cincinnati, O. JENNINGS, Irving C. (if 1924) Pres, (for mail) Nash Engineering Co., and 138 Flax Hill Rd.. South Norwalk, Conn. ' JENNINGS, Richard A. (A 1937) Chief Engr. (for mail) Keith Massachusetts Corp., 539 Washing ton SL, and 695 Atlantic Ave., Boston, Mass. JENNINGS. Stanley A. (Af 1935). AssL Chief Engr., Trane Co. of Canada. Ltd., 4 Mowat Ave., and (lor mail) 17 Avion Ave., Toronto, OnL, Canada. JENNINGS, W. G. (A 1930) Resident Vice-Pres. Sl, and 3342 W. 33rd Ave., Vancouver, B. C., Canada. JOHNSTON, Robert McC. (/ 1937) Instructor, DepL of Mech. Engrg., Virginia Polytechnic Institute (for mail) Box 548 and 707 Main St., Blacksburg, Va. JOHNSTON, Rodney M. (A 1938) Steam & Gas Htg. Sales (for mail) New York State Elec. & Gas Corp., 115-117 Main SL, and 274 Genesee St., Lockport, N. Y. JOLLEY, Edward M. (A 1939) Sales Engr. (for mail) The Marley Co., 3001 Fairfax Rd., Kansas City. Kan., and 5714 Woodland, Kansas City Mo. JONES, Alfred (Af 1928) Chief Consulting Engr. (for mail) Armstrong Cork Co., Box 540, and 402 N. President Ave., Lancaster. Pa. . JONES, Alfred L. (Af 1920) Plbg. & Htg. Con tractor (for mail) 431 Greenwich Ave., Green wich, and Box 121, Riverside. Conn* JONES, Allan T. (Af 1937; J 1935) Chief Engr. (for mail) Minneapolis-Honeywell Regulator Co.. (for mail) S. A. Armstrong, Ltd., 720 Bathurst 797 Beacon St., Boston, and 20 Chapel St., Brookline, Mass. St., and 325 Kingswood Rd., Toronto, Ont., Canada. JENNINS, Henry H. {Life Member; M 1901) 29 JONES, Bernard G. (Af 1928) Mgr. (for mail) Greyshiels Ave.. Leeds, 6, England. JENSON, Jean S. (Af 1912) (for mail) Jean S. Ranch, Falfumas, Tex., and 1634 West 106th SL, Chicago, III, JESSUP, Benjamin H. (Af 1937) Pres, (for mail) Richards & Jessup Co., Inc., 615 Main St., Stamford, and 48 Field St., Genbrook. Conn. JOHNS, Charles F. (M 1939; A 1931) Chief Engr., Enterprise Foundry Co., Ltd., and (for mail) Sackville, Nr. B., Canada. . Acme Fan 8c Blower Co,, Ltd., 868 Arlington St., and 542 Raglan Rd., Winnipeg, Man., Canada. JONES. Edwin (Af 1933; J 1924) Engr. and Estimator (for mail) Watt Plumbing, Heating & Supply Co., 60S S. Cincinnati, and 1436 East 17th Place, Tulsa, Okla. JONES. Edwin A. (M 1919) Consulting Engr. (for mail) 4381 N. Alpine Ave., Milwaukee, Wis. JONES. Edwin F. (Af 1923) Utilities Engr.. City of SL Paul, 21G Courthouse. f{^ *-*" " HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 JONES, Harold L. (Af 1920) Supt. (for mail) W. W. Farrier Co., 44 Montgomery St., Jersey City, and 11 Cambridge Rd., Glen Ridge, N. J. JONES, Hubert L. (A 1938) Sales Engr. (for mail) B. Segatl Co., 317 Travis St., and 1901 Centenary Blvd., Apt. D-27, Shreveport, La. JONES, James T. (A 1939) Air Cond. Engr. (for mail) Empire District Electric Co., and 328 N. Jackson, Joplin, Mo. JONES. John P. (Af 1937) Pres, (for mail) John Paul Jones, Cary and Miliar, Cons. Engrs., 448 Terminal Tower. Cleveland, and 3161 Scar borough Rd., Cleveland Heights. O. JONES, Lawrence K. (M 1939) Mgr. Special Test Section (for mail) Pittsburgh Testing Laboratory, 1330 Locust St., and 320 S. Aiken JOANvEe.S, ,PitStspbruargguhe, P(aA. f 1936) Pres, (for mail) Sprague Jones, Inc., 1116 Madison Ave., and 3769 S. Lockwood Ave., Toledo, O. JOSES, William T, (M 1915) (presidential Mem ber) (Pres., 1933; 1st Vice-Pres., 1932; 2nd Vice- Pres., 1931; Council, 1925-1933) Treas., Barnes .& Jones, 128 Brookside Ave., Jamaica Plain, Boston, and (for mail) 16 Harvard St., Newton- JOvRillDe,AMNa, sRs.ichard C.* (A 1940; J 1935; S 1933) Instructor (for mail) University of Minnesota, Engrg. Experiment Station, Room 209, and 805 Beacon St., S. E., Minneapolis,- Minn. JOSEPHSON, Simon {J 1936) Pres, (for mail) Astor Plumbing & Heating Corp., 1134 Bedford Ave., and 199 E. 2nd St., Brooklyn, N. Y. JOYCE, Harry B. (M 1922) Consulting Engr. (for mail),Harry B. Joyce, Registered Engineer, 616 Commerce Bldg., and 501 Liberty SC, KARCHMER, Jacob H. (A 1936) Mgr. (for mail). Karchmer Co., 600-14 N.' Jefferson Ave., and 1318 Roanoke Ave.. Springfield, Mo. KARGES. Albert (A 1935) Mgr., The James Stewart Mfg. Co., Ltd., and (for mail) 37 Perry ' St., Woodstock, Ont., Canada. KARLSON, Alfred F. (Af 1918) Chief Engr. (for mail) Parks-Cramer Co., 970 Main St., Fitchburg, * and 186 Prospect St., North-Leominster, Mass. KARLSTEEN, Gustav H. (Af 1935) Plant Engr.. Dunlop Tire & Rubber Corp., Buffalo, and (for mail) Box 55, Route 1. Tonawanda, N. Y. KARSUNKY, William K. (Af 1939) Consulting Engr. (for mail) 1223 Connecticut Ave.. N. W., Washington, D. C., and Kensington, Md. KARTORIE, V. T. (J 1935; S 1933) Sales Engr. (for mail) York Ice Machinery Corp., and 1513 Third Ave., York, Pa. - KAUFMAN, Hiram J. (Af 1937) Htg.-Vtg. Engr., Commonwealth & Southern Corp., Consumers Power Bldg., Jackson, and (for mail) 13215 Roselawn Ave., Detroit, Mich. KAUP, Edgar O. (Af 1937) Chief Engr., Air Cond. Div., W. R. Ames Co., 150 Hooper St., San Francisco, and (for mail) 1129 Curtis St., Albany, KACWalAif.SE, Sumlo (Af 1936) Chief Htg. Engr., Eiten Juhin Kyoku-Manchoukuo, and (for mail) 614 Suchikodo, Hsinking, Manchoukuo. KEANE, Gerard F. (Af 1939) In charge of Engrg. (for'mail) Cooney Refrigeration Co., 228 Walton St., and 135 Jamesville Ave., Syracuse, N. Y. KEARNEY, Joseph S. (Af 1939) Pres., North western Heating & Plumbing Co., 1465 Sherman Ave., and (for mail) 2001 Bennett Ave,, Evans KEtoAnT, I1N11.G, Arthur J. (Af 1937) Sales Engr.. JUENriGe,, PJao.hn S. (Af1930; A 1923) Heating, Piping and Air Conditioning Contractor & Engr. (for mail) 2409 W. Greenfield Ave.. and 1516 S. Layton Blvd,, Milwaukee, Wis. JUNKER, William H. (Af 1936) Plant Engr., Emery Industries. Inc., 4300 Carew Tower, and (for mail) 6068 Dryden Ave., Cincinnati, O. K Powers Regulator Co., 2720 N. Greenview Ave., and (for mail) 4429 W. Congress St., Chicago, 111. KEELAND, Burdette W. (A 1938) Vice-Pres. (for mail) RoIIosson-Keeiand Co., 3714 Main, and 2723 Kipling, Houston, Tex. KEENEY, Frank P. (A 1915) Pres, (for mail) Keeney Publishing Co., 6 N. Michigan Ave., and 7059 S>outh Shore Drive, Chicago, III. KEHM, Horace S. (Af 1928) Pres, (for mall) The Kehm Corp., 51 E. Grand Ave., and 3240 KACZENSKI, Chester (A 1939; J 1933) 315 N. Spruce St., Winston-Salem, N. C. KADEL, George B. (A 1940; J 1938) Engr., E. R. Squibb & Sons. 25 Columbia Hts., and (for mail) Lake Shore Drive., Chicago, 111. KEITH, James P,, (Af 1938) Consulting Engr., - Vice-Pres., Canadian Domestic Engineering Co., Ltd., 1440 St. Catherine St-, W., Montreal, and (for mail) 5196 Durocher Ave., Outremont, P. Q,, 237 Garfield Place, Brooklyn, N. Y. KAERCHER, C. M. H. (M 1937) Managing Dir. (for mail) Central Bureau for Heating & Air Conditioning, 3030 Euclid Ave-, Cleveland, and 2560 Ashurst Rd., University Heights, O. KAHN, Charles R., Jr. (J 1939) Sales Engr., New York Air Conditioning Co., 239 West 39th St., New York, and (for mail) 118 Wood Lane, Woodmere, L. I., N. Y. KAISER, Charles W. (A 1939; J 1938) Instructor, Board of Education, City of New York, New York Vocational High School, 21 W. 138th St., New York, and (for mail) 37-35-57tb St., Woodside, Canada. . KEITHLEY, Frank R. (/ 1939) Sales Engr., Malvin & May, Inc., 2427 S. Michigan, and (for mail) 1433 E. 65th PI., Chicago, 111. KELBLE. Frank R. (M 1928) Vice-Pres. & Mgr. (for mail) Huffman-Wolfe Co. of Philadelphia, 4660 N. 18th St., Philadelphia, and 305 Pleasant KEALveL.A, G, lWenasliddeo,nPaB. . (Af 1939) Mgr. Air Cond. Dept, (for mail) Fairbanks, Morse & Co., 217 S. Eighth St., and 910 Goodfellow, St. Louis, Mo. KELLER, George A. (A 1938) Asst. Supt. of Engrg. & Maintenance, Abraham & Straus. Inc., L. I.. N. Y. 422 Fulton St., Brooklyn, and (for mail) P. O. KAISER, Fred (Af 1935) Branch Mgr., Tempera ture Control, 415 Brainard St., Detroit, and (for Box 481. Wantagh, L. I., N. Y. * KELLEY, James J. (A 1924) Fuel Oil & Burner mail) 487 Westchester Rd., Grosse Pointe Park, Aast. (for mail) Colonial Beacon Oil Co., 378 Mich. KAJUK, Andrew E. (Af 1936) Engr., U. S. Govt., War Dept., Munitions Bldg., and (for mail) 5316-4th St., N. W., Washington. D. C, KALINSKY, Alex G. U 1936; S 1934) Htg. Engr. (for mail) American Radiator & Standard Sani tary Corp., and Y.M.C.A., Elyria, O. KAMMAN, Arnold R. (A 1925; J 1921) (for mail) Arnold R. Kamman Co., 493 Franklin St., Buffalo, and R. F. D., No. 3, Hamburg, N. Y. KAPPEL, George W. A. (Af 1921) Pres.-Treas. (for mail) Camden Heating Co., 8 Market St., Camden, and 347 W. Kings Highway, Haddon- fteld, N. J. KARAKASH, Theodore J. (A 1940; J 1936) Head Engr. (for mail) Carrier Air Cond. Dept., G. & A. Baker, Ltd., P. O. Box 468, Istanbul, Turkey. Stuart St., Boston, and 142 Governors Ave., Medford, Mass. - KELLEY, Robert D. (Af 1937) Pres, (for mail) Sunbeam Heating & Air Conditioning Co.. 346 Peachtree St., N. E., and 668 Elmwood Drive, KEALtlLaOntGa,GG,a.Alfred (Life Member; Af 1916) (Council, 1920-1921; 1923-1924) Consulting Engr., 89 Franklin St., Boston, and (for mail) 6 Haw KEthLoLrOneGSGt.,, BWelimnsotnot.nMTas.s.(A 1938) Engr. and . Secy.-Treas. (for mail) Kelbur Corp., P. O. Box 27, and 1920 Beechwood Rd., Little Rock, Ark. KELLY, Charles J. (Af 1931) Agent (for-mail) James P. Marsh Corp., 155 East,44th St., New- York, N. Y., and 440 Fairmount Ave., Jersey City. N. J. 38 ROLL OF MEMBERSHIP KELLY, John G. (A 1919) Pres.. John G. Kelly Inc., 210 East 45th Si., New York, and (for mail) 374 Park Ave-, Yonkers, N. Y. KELLY Wilbur C. (Af 1935) Field Engr. (for .mail) Iron Fireman Mfg. Co. of Canada. Ltd., *602 King St., W., and 58 Elmsthorpe Ave., KILNER, John S. (Af 1929) Sales Engr., Clarage Fan Co., 7310 Woodward Ave.. and (for mail) 1091 Seminole Ave., Detroit, Mich. . . . KILPATRICK, WUllam S. (Af 1923) Partner, W. S. Kilpatrick & Co., 1100 East 33rd St.. Los Toronto, Ont.. Canada. KENDALL, Edwin H. (Af 1930) Sales Engr., ' English & Lauer, Inc-, 1978 S. Los Angeles St., Los Angeles, Calif. " KENNEDY, Mflron (A 1936; J 1930) Sales Engr., York Ice Machinery Corp., 5051 Santa Fe Ave., Los Angeles, Calif. KENNEDY, Owen A. {J 1938; S 1933) Vtg. Engr., Angeles, Calif. .- KIMBALL, Charles W. (Af 1915) Treas. (for mail) Richard D. Kimball Co., 6 Beacon St., Boston, and 65 Prescott St., West Medford, Mass.' ` KIMBALL, Dwight D.* (Af 1908) (Presidential Member) (Pres., 1915; 2nd Vice-Pres., 1914; Board of Governors, 1912-1916) Consulting Engr. (for mail) Room 1728, Grand Central Terminal 112 Dixie Highway, South Fort Mitchell, Ky. KENNEY. Thomas W. (Af 1937) Sales Engr., Bldg., and 145 West 58th St., New York, N. Y. KIMBLE. Carl W. (J 1938) Owner-Partner. E. J. Deckman Co., 603 Oliver Bldg., and .(for mail) 171 Kendall Ave-. Bellevue, Pittsburgh, Pa. KENT, Laurence F. (A 1927; J 1924) Pres, (for Advance Heating & Sheet Metal Works, 3l5-24th St.. Rock Island, III. K1MMELL, Phillip M. (J 1936) Asst. Mech. mail) Moncrief Furnace Co., P. O. Box 1673 and 1515 Momingside Drive, N. E., Atlanta, Ga. KENT, Richard L. (Af 1936) Dist. Mgr. (for mail) Engr., Engrg. & Maintenance Dept.. Eastman Kodak Co., Kodak Park Works, and (for mail) 180 Rodessa Rd., Rochester, N.'Y. . Trane Co. of Canada, Ltd., 303-365 Hargrave KINCAIDE, Merrill C. (Af 1939; A 1937; / 1936) St., and 104 Wellington Crescent, Winnipeg, Air Cond. Engr. (for mail) Timken Silent Auto Man., Canada. KEPLER, Donald A. (J 1936; 5 1934) Vtg. Engr., matic Div., 100-400 Clark Ave., and 1160 Seward Ave., Detroit, Mich. . . New York Stock Exchange Bldg. Co., 20 Broad KINDORF. Harry L. (Af 1937) Owner, The St., New York, N. Y., and (for mail) 30 Maple wood Ave., Maplewood, N. J. KERN, Joseph F., Jr. (A 1937) Asst. Editor, Heating & Ventilating, 148 Lafayette St., New York, and (for mail) 88-24-166th St., Jamaica, L. 1., N. Y. Kindorf Co., 46. Oakwood St., San Francisco, Calif. KINDORF, Orian (A 1938) Vice-Pres. and Mgr. (for mail) General Air Conditioning Co., 1313. J St., and 3433 N St., Sacramento, Calif. KING, Arthur G. (Af 1936) Consulting Engr., 35 KERN. Raymond T. (Af 1927) Chief Engr.. Jennison Co., 17 Putman St., Fitchburg, and (for mail) 51 Ciafiin St., Leominster, Mass. KERR, William E. (Af 1937) Sales Repr., Barnes S. Dearborn St.,-Chicago, 111. KING, Lon D. (A 1937) Air Cond. and Htg. (for mail) 2325 R St., Lincoln, Nebr. KING, Roy L. .(J 1936; 5 1933) Air Cond. Engr.. & Jones, Inc; (of Boston, Mass.), 1201 Hyatt Ave., Columbia, S. C. ` KERSHAW, Melville G. (Af 1932; A 1926; J 1921) Vtg. and Air Cond. Engr. (for mail) E. I. DuPont de Nemours & Co., Wilmington, Del., and 3713 North 21st St., Philadelphia, Pa. KESSLER, Clarence F. (Af 1938) Asst. Prof. Mech. Engrg. (for mail) University of Michigan, 241 W. Engineering Bldg., and 1756 Broadway, Ann Arbor, Mich. KESSLER, Maurice E. (Af 1937) Mgr. (for mail) Pioneer Heating-Cooling Co., 901 Niagara St., Mayflower-Lewis Corp., Duluth & E. 7th Si., St. Paul, and (for mail) 2538 Clinton Ave., S,, Minneapolis, Minn. ' KINGSLAND, George D. (Af 1935) Vice-Pres. (for mail) Minneapolis-Honeywell Regulator Co., 2753 4th Ave., S., and 2036 Queen Ave., S., Minneapolis, Minn: KINCSWELL, William E. (Af 1935) Pres, (for mail) William E. Kingswell, fnc., 3707 Georgia Ave., N. W.. and 2739 Macomb St.,. N. W., Washington, D. C. . KINNEY, Aldon M. (Af 1936) Pres, (for mail) and Falls Station, P. O. Box 664, Niagara Falls, N. Y. A. M. Kinney, Inc., Cons. Engrs., 1820 Carew Tower, and 3812 Beech St., Mariemont, Cincin KETTER, Jack W. (J 1937) Design Engr.. Krenz & Co., 5114 W. Center St., and (for mail) 3042 N. 2nd St., Milwaukee, Wis. KEYSER. Herman M. (A 1937) Sales Engr., Murray W. Sales & Co.. Detroit, and (for mail) 10703 Hart Huntington Woods, Royal Oak, Mich. nati, O. KIPE, J. Morgan (Af 1919) Dir. of Education, Anthracite Merchandising School, Primos, and . (for mail) 801 Homestead Ave., Beechwood, Del. ` Co., Pa. - KIPP, Theodore (Af 1937) Pres., Kipp-Kelly. Ltd., 68 Higgins Ave., and (for mail) 1030 Wellington KICZALES, Maurice D. (M 1935) Mech. Engr., U- S. Army Motion Picture Service, 726 Jackson Crescent, Winnipeg, Man., Canada. KIRKBRIDE, J. Owen (Af 1938) Partner (for Place, N. W., and (for mail) 3000 Connecticut Ave., Washington, D. C. - KIDD, Charles R. (A 1938) Mgr. & Pres.. C. R. Kidd Co., 712 N. Broadway, and (for mail) 611 N. W. 28th-St., Oklahoma City, Okla. KIEFER, Carl J. (Af 1922) Vice-Pres. (for mail) mail) Parent & Kirkbride, 1715 Rittenhouse St., Philadelphia, Pa., and 1121 Eldridge Ave., W. Collingswood, N. J. ' . KIRKENDALL, Horton T. (A 1938) Sales Repr., Htg. Equip., 291 Catalpa PI., Pittsburgh (16) Pa. SchenJey Products Co., 607 Schmidt Bldg., and KIRKPATRICK, Arthur H. (Af 1935; J 1931) .984 Lennox PI., Avondale. Cincinnati, O. , Salesman, Ilg Electric Ventilating Co., 415 KIEFER,. E. J. (A 1932; J 1928) Treas.. H. C. Brainard. and (for mail) Hotel Webster Hall, Archibald Co., 406 Main St., and (for mail) 108 Detroit, Mtch. N. 6th St., Stroudsburg, Pa. KISTLER, Milton. L. (A 1936) Owner-Engr., KIESLING, Justin A. (Af 1930) Pres, (for mail) Kistler's Sheet Metal Works, 1952 Antoine St., Robischung-Kieslittg Contracting Corp., 4848 Mobile, Ala. Main St., and 1602 Stuart St., Houston, Tex. KILDAY, John A. (A 1938) Salesman, The Birael Co., 305 Walnut, and (for mail) 23 Cal houn St., Cincinnati, O. KILLIAN, Thomas J. (A 1937) Htg. Contractor, 118 Belvidere St., Waukegan, 111. KILLIAN, Vic. J. (A 1937) Pres, (for mail) V. J. : Killian Co., 907 Linden Ave., and 1348 Edgewood Lane. Winnetka, III. KILLOUGH, Robert E. (A 1938) Engr., Standard . Oil Co. of Pennsylvania, 1618 N. Broad St., and (for mail) 2108 E. Chelten Ave., Germantown, KITAURA, Shigeyukl (Af 1918) 191 Gotanda 6 Chomei Shiniagawa-ku, Tokyo, Japa *. ! KITCHEN, Francis A. (A 1927; J 1923) Pres. (for mail) American Warming & Ventilating Co., 1514 Prospect Ave., Cleveland, and 2077 Campus Rd., South Euclid, O. KITCHEN, John H. (Life Member; Af 1906) Pres. & Mgr. (for mail) John H. Kitchen & Co., 1016 Baltimore Ave., and 5015 Westwood Terrace, Kansas City, Mo. KITCHEN, William H. J. (A 1938) Chief Engr., Philadelphia, Pa. Bermuda Trading Co., Reid St., and (for mail) P. O. 271, Hamilton, Bermuda. 39 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 KLEIN, Albert R. (Af 1920) Managing Dir. (for mail) Lufttechnische Gesellachaft, Stuttgart-W, Konigstrasse S4, and Heidehofstrasse 40, Stutt KONZO, Seichi* (Af 1937; A 1936; 7 1932) Special Research Asst. Prof., University of Illinois. Engrg. Experiment Station, 102 Mech. Engrg. Laboratory, and (for mail) 1108 West gart. Germany. KLEIN, Edward W. (M 1917) Dist. Repr. (for mail) Warren Webster fit Co.. 152 Nassau St., N. W., and 456 Peachtree Battle Ave., Atlanta, Ga. KLEINKAUF, Henry (Af 1938; 7 1937)-Branch Mgr. (for mail) Natkin & Co., 18th & Howard Sts., and 6312 Florence Blvd., Omaha, Nebr. KLENERT, William (A 1938) Htg. Expert. Davis fit Warshow, Inc-, 75 Ludlow St., New York, and (for mail) 45-50-159th St., Flushing. L. I., N. Y. KL1E, Walter (Af 1915) Pres, (for mail) The Smith & Oby Co.. 6107 Carnegie Ave., Cleveland, and 18411 S. Woodland Ave., Shaker Heights, O. KLIEFOTH, Max H. (A 1939) Treas. (for mail) Stoughton St., Urbana, 111. KOOISTRA. John F. (Af 1933) Branch Mgr. (for mail) Carrier Corp., Room 701, 625 Market SL. San Francisco, and 1245 Laguna St., Burlingame. Calif. KORN, Charles B. (Af 1922) Reber-Kom Co.. 817 Cumberland SL, and (for mail) 1022 S. Eighth St., Allentown. Pa. . ROSTER, Howard H. (7 1939) AssL Prof. Mech. Engrg. (for mail) The George Washington University, and 1312 Saratoga Ave., N. E.. Washington, D. C. KOTHE, Frederick H. (A 1937) Resident Engr. (for mail) Carrier Engineering S. A., Ltd., Box 2421, and 258 Florida Rd., Durban, Union of Research Products Corp.. E. Washington Ave., and 1 Langdon. Madison, Wis. KLUGE, Burnett M. (7 1938) Sales Engr., Bayley Blower Co., and (for mail) 405 N. 39th St., Milwaukee, Wis. KNAPP, Andrew E. (Af 1937) Asst. Chief Engr. (for mail) Kelvinator Corp.. 14250 Plymouth Rd., and 8059 SorTento, Detroit, Mich. KNAPP, Donald S. (A 1936) Branch Mgr. (for mail) Chamberlin Metal Weather Stnp Co., South Africa. KOTZEBUE, Robert W. (A 1937) Mgr., Air Cond. Dept, (for mail) Straus-Frank Co., 301 S. Flores, and 438 Paseo Endnal, San Antonio. Tex. KRAMER, Conrad (7 1938) Air Cond. Engr., 1611 Westminster St., Providence, and (for mail) 21 Comstock St.; Pawtucket, R. I. KRAMIG, Robert E., Jr. (A 1933) Vice-Pres- Treas. (for mail) R. E. Kramig & Co., Inc., 222-4 E. 14th St., Cincinnati, and 115 Linden Drive. Inc., 2400 Hennepin Ave., and 4607 Wooddale Ave., Minneapolis. Minn. KNAPP, Joseph H. (Af 1936) Designing Htg.-Vtg. Equip., Utica Products Corp., and (for mail) 111 Lowell Ave., Utica, N. Y. KNEPPER, H. H. (A 1938) Erection Engr. (for mail) Minneapolis-Honeyweil Regulator Co., 378 Saunders-Kennedy Bldg.. Omaha, Nebr., and 122 Gold St., Kendallviile, Ind. KNIBB, Alfred E. (Af 1930) Htg. Engr. (for mail) L. L. McConachie Co., 1003 Maryland Ave., and 9333 E. Jefferson Ave., Detroit, Mich. KNOWLES, Elwtn L. {A 1937) Owner, Knowles Air Conditioning, 1324 Marshall St.. N. E., and (for mail) 36 Oliver Ave., S., Minneapolis. Minn. KNOWLES, Frank R. (A 1937) Dir. Commercial Wyoming. O. * KRAMINSKY, Victor (Af 1936) Managing Dir. (for mail) Air Conditioning fit Engineering, Ltd.. 123d Victoria SL, Westminster, and 608, Howard House, Dolphin Square, London, S. W. 1, England. KRATZ, Alonzo P.* (Af 1925) (Council, 1938 1939) Research Prof, (for mail) Dept, of Mech. Engrg.,^ University of Illinois, and 1003 Douglas at., uruana, m. KRAYENHOF, Harold G. (A 1937) 231 Dick enson Ave., Swarthmore, Pa. KRENZ, Alfred S. (Af 1937; A 1935) Pres.-Treas. (for mail) Krenz & Co., Inc.. 5114 W. Center St., Milwaukee, and 1766 N. 74th SL, Wauwatosa, Wis. KREZ, Leonard (A 1935) Secy, (for mail) Paul J. Krez Co., 444 N. LaSalle St., and 4716 N. Engrg. Dept., Pennsylvania Electric Co., 535 Paulina St., Chicago. 111. * Vine St., Johnstown, Pa. KRIBS, Charles L.. Jr. (Af 1935) Pres, (for mail) KNOX, John C. (A 1938) Secy.-Treaa. (for mail) Kribs & Landauer, 404 Dallas Gas Bldg., and Waterloo Register Co., and 176 Gates- St., 3608 Drexel Ave., Dallas, Tex. . Waterloo, la. KNUDSEN, William R. (Af 1937) Consulting KRIEBEL, Arthur E. (Af 1920) Sales Engr. (for mail) Haynes Selling Co.. Inc.. 1124.-Spring Engr., 897 S. 8th St., San Jose, Calif. Garden St.. Philadelphia, and Berwyn, Chester KOCH, Albert H. (Af 1938) Branch Mgr.. Minne apolis-Honeywell Regulator Co., 101 Marietta St. Bldg., and (for mail) 3687 Peachtree Rd.. Co., Pa. . KROEKER, J. .Donald (M1935) Consulting Engr. (for mail) 926 Failing Bldg., and 6831 N. 6. Atlanta, Ga. KOCH, Arthur C. (A 1938) Mgr., A. C. Koch & Co., 704 Anita SL. Houston, Tex. KOCH, Richard G. (A 1935) Househeating Engr. (for mail) Milwaukee Gas Light Co., 626 E. Wis consin Ave., and 734 N. 34th SL, Milwaukee, Wis. KOEHLER, C. Stewart (A 1936) Sales Engr., Minneapolis-Honeywell Regulator Co., . 801 Second Ave., and (for mail) 4374 Richardson Ave.; New York, N. Y. KOFOED, V. Beckwith (A 1937) R. F. D. No. 3, Chagrin Fails, O. KOHLER, John C. (A 1939) Partner (for mail) John C. Kohler Co., 554 N. 16th SL, and 629 Crestview Rd., Philadelphia, Pa. KOHLER. Walter J., Jr. (A 1933) Secy, (for mail) Kohler Co., and "Wlndway," Kohler, Wis. KOLB, Fred W. (Af 1938) Principal, Industrial & Bldg. Equipment (for mail) 598 Monadnock Bldg., and 82 Macondray St., San Francisco, Calff. KOLB, Robert P- (Af 1939) Prof, of Heat-Power Engrg. (for mail) Worcester Polytechnic Inst-, and 215 May SL, Worcester, Mass. ROLLAS, WU1 J. (Af 1939) Chief Engr., Montag Stove & Furnace Works, 2011 N. Columbia Blvd., and (for mail) 6104 N. Missouri Ave., Siskiyou St., Portland. Ore. KROEKER, Sanford P. (71938) Engr.. Governair Corp., 605 -W. Main SL, and (for mail) 2203 S.. Agnew, Oklahoma City, Okla. KRUEGER, James 1. (M 1921) Mfrs. Repr., Illinois Engineering Co., and Whitlock Coil Pipe Co. (for mail) 357 Ninth SL, San Francisco, Calif. KRUSE, W. C., Jr. (Af 1938) Repr. (for mail) American Air Filter CoT, 24 Commerce St.. Newark,and 32 UniversityCourt, S. Orange, N.J. KUBASTA, Robert W. (7 1936) Sales Engr. (for mail) Carrier Corp., 302 S. Geddes SL, and 405 Comstock Ave., Syracuse, N. Y. KUCHER, Andrew A. (Af 1938) Mgr. Air Cond. Engrg., Frigidaire Div. (for mail) General Motors Sales Corp., Taylor SL, and 210 Greenmount Blvd.. Dayton, O. KUCINSKI, William V, (A 1939) Chief Engr.. Atlantic Utilities Institute. Inc., 800 McCarter Highway, and (for mail) 10 Peck Ave., Newark, N. J. KUECHENBERG, William A. (Af 1937) Pres- (for mail) R. B. Hayward Co., 1714 Sheffield Ave., Chicago, and 427 Elmore Ave., Park Ridge, 111. KUEHN, Walter C. (A 1933) Kuehn Heating & Ventilating Co., 915 Seventh Ave., S., Minne apolis, Minn. ' Portland. Ore. 40 ROLL OF MEMBERSHIP KUEMPEL, Leon L. (Af 1936; 7 1929) Hughes Heating & Air Conditioning Co.. 125 North Jefferson SL, and (for mail) 200 Briarcliff Rd., Dayton, O. KUGEL, H. Kenneth (Af 1938) Smoke Regulation Engr. (for mail) Div. of Smoke Regulation and Boiler Inspection, Government of the District of Columbia. District Bldg., and 3825 Morrison St., N. W., Washington, D. C. KUHLMANN, Rudolf (Af 1928) Ameresco. Inc., 50 Church St.. New York, N. Y. KUMMER, Calvin J. (7 1938) Engr. (for mail) Carrier Corp., 7-122 Merchandise Mart Bldg., and 4820 N. Winchester, Chicago, 111. KUNEN, Herbert (7 1938) Mech. Engr. (for mail) Anemostat Corp. of America, 10 East 39th St., New York, and 117-14 Union Turnpike, Kew Gardens. L. I.. N. Y. KUNTZ, Edward C. (7 1937) Sales Engr.. Ham mond Sheet Metal Co;, 119 Cass Ave., and (for mail) 4014 Loughborough Ave., SL Louis. Mo. K.UNZOG, Theodore W. (Af 1939) Chief Engr., Hudson Heating, Ventilating & Air Conditioning Co., 158 Tonnele Ave., and (for mail) 134 Corbin Ave., Jersey City, N. J. KUREK, Ted C. (Af 1938) Mech. Engr., HenridLowry Engineering Co., 114 West 10th St.. Kansas City, and (for mail) R. F. D. No. 2, Liberty, Mo. KURTH, Frank J. (Af 1937) Tech. Dir. (for mail) . Anemostat Corp. of America, 10 E. 39th Sl, and 180 Cabrini Blvd., New York, N. Y. KURTZ, Robert W. (7 1936) Air Cond. & Sales Engr. (for mail) Air Conditioning Co., 1017 Sampson, Houston, Tex., and 1513 West Lake. Minneapolis, Minn. KWAN, I. K. (Af 1933) Gen. Mgr., The China ' Engineering Co., 30 Brenan Rd., Shanghai, China. LANGE, Fred F. (A 1934) Pres, (for mail) The Mechanical Service Co., 602 Pence Bldg.. Minne apolis, and 356 N. Cleveland Ave., St. Paul, Minn. LANGE, Robert T. (Af 1936) Engr. (Test Dept.) Hartzell Propeller Fan Co., Box 909, and (for mail) 224 Jackson SL. Piqua, O. LANCENBERG, Everett B. (Af 1914) Owner (for mail) Langenberg Hearing Co., 3800 West Pine Blvd., St. Louis, and 223 E. Adams St., Kirkwood, Mo. LANNING, E. K. (A 1927) AssL Secy. & Sales Mgr. (for mail) Warren Webster St Co., Camden, and Clayton, N. J. LANOU, J. Ernest (Af 1931) Mgr. (for mail) F. S. Lanou 8c Son, 90 St. Paul SL, and 48 Brookes Ave., Burlington, Vl LARKIN. Paul (A 1937) Service Mgr.. Minneapolis-Honeywell Regulator Co., 378 Saunders-1 Kennedy Bldg., and (for mail) 4667 Pierce, Omaha, Nebr. LaROCQUE, Paul E. (A 1937) Htg. Contractor. 86 D'Abraham Hill, Quebec. P. Q., Canada. LaROI, George H., II (7 1936) Adv. Mgr. (for mail) McDonnell & Miller, Room 1316, Wrigley Bldg., and 4443 N. Monitor Ave., Chicago, IU. LARSON, Carl W. (Af 1936) Sales Engr., Bames 8c Jones, Inc., Rm. 1219, Industrial Trust Bldg.. Providence, R. I., and (for mail) 641 Hyde Park Ave.. Roslindale, Mass. LARSON, Clifford P. (A 1939; 7 1936) (for mail) The Insulite Co., 2011 Pillsbury Ave., Minne apolis, Minn. LARSON, Gustus L.* (Af 1923) (Presidential Member) (Pres., 1936; 1st Vice-Pres., 1935; 2nd Vice-Pres.. 1934; Council. 1929-1937) Prof., Steam and Gas Engrg., and Chairman of Dept, of Mech Engrg. (for mail) University of Wis consin. Mech. Engrg. Bldg., and 1213 Sweetbriar L Rd.. Shorewood Hills, Madison, Wis. . . LADD, David (Af 1938) Mgr., Philadelphia Branch (for mail) The Powers Regulator Co., 2240 N. Broad SL, and 305 E. Wadsworth SL, Phila- deiphia. Pa. - LAFONTAJNE, Edmund A. {A 1038) Sales Mgr.. Kelvinator of Canada, Ltd., 1632 SL Catherine Sl, \V.. and (for mail) 2382 Park Row West. Montreal. P. Q., Canada. LaRUE, J. A. Delphis (A 1939) Mgr. (for mail) Roofers, Inc., 726 Atwater Ave., and 4309A Delaroche St., Montreal, P. Q., Canada. . LaRUE, Perry (Af 1938) Dir. of Bldgs, and Grounds (for mail) Independent School District, 629 Third St., and 1321-43rd, Des Moines, la. LaSALVIA. James J. (Af 1930) Mech. Engr.. Frigidaire Div.. General Motors Sales Corp., and LAGODZINSKI, Harry J. (A 1927; 7 1920) Sales (for mail) 2250 Emerson Ave., Dayton, O. Engr. (for mail) Iig Electric Ventilating Co., 220 LASETER, Frank L. (Af 1938) Mgr., Hearing N. LaSalle St., Chicago, and Crystal Lake, 111. Dept., Chief Engr. (for mail) Atlanta Gas Light LsMONTAGNE, Arthur F. (A 1936) Sales Mgr.. Htg. Div. (for mail) Gurney Foundry Co., Ltd., Co., 243 Peachtree St., and 1206 Peachtree SL, Atlanta, Ga. P. O. Box 277, Montreal, and 24 Prince Arthur LASKARLS. Nicholas G. (5 1938) David Ranken St., St. Lambert, P. Q., Canada. Jr. School of Mech. Trades, 4437 Finney Ave., LANCE, Joseph F. (Af 1923) Supt. (for mail) and (for mail) 759 Aubert Ave., SL Louis, Mo. . Harrigan & Reid Co., l365.Bagley Ave., and * 14816 Ashton, Detroit, Mich. LANDAU, Mitchel (Af 193/) Mgr.. Hearing & Air Conditioning Depts. (for mail) ABC Oil Burner 8t Engineering Co., Inc.. 2012-14 Chestnut SL, and 1934 Nedro Ave., Philadelphia, Pa. LANDAUER, Leo L. (Af 1937 ; 7 1932) Member of Firm (for mail) Kribs fit Landauer, 404 Dallas Gas Bldg., and 4433 Stanhope. Dallas, Tex. LANDERS, John J. (Af 1930; 7 1924) Mfrs. Repr. (for mail) 701 Crosby Bldg., Buffalo, and 120 Burroughs Drive, Snyder, N, Y. LAUCKNER. Charles G., 3rd (7 1938) Jr. Engr., General Electric Co., 920 Western Ave., Lynn, and (for mail) 37 Porter SL, East Lynn, Mass. /LAUER, Harold B. (Af 1930) Vice-Pres. (for mail) English 8c Lauer, Inc., 1978 S. Los Angeles SL, and 1121 S. Hayworth Ave.. Los Angeles, Calif. LAUER, Rodney F. (A 1940; 7 1936) Sales Engr. (for mail) York Ice Machinery Corp., 1238 N. 44th St., Philadelphia, and 236 Glentay Rd., Lansdowne. Pa. LAUFKETTER, Fred C. (Af 1936) Supt. & Chief LANDES, Bates E. (Af 1938) Mech. Engr. (for Engr. (for mail) Jefferson Hotel, 12th & Locust mail) 915 Hubbell Bldg., and 1603*47th SL, Sts., and 7056 West Park Ave., St. Louis, Mo. Des Moines, la. LMJTERBACH, Henry, Jr. (Af 1935) Mech. LANDES, Benjamin D. (A 1937) H. K. Porter Engr., In Charge of Contract Dept, (for mail) Co.. 49th & Harrison Sts., Pittsburgh. Pa. (carrier Corp., Merchandise Mart, and 6959 LANDEWIT, Caslmir J. (A 1939; 7 1937) Merrill Ave., Chicago, III. 115-95 226th St., St. Albans, L. I., N. Y. LAUTZ, Fritz A. (Af 1936) Sales Engr. (for mail) LANE, D. Duffy (Af 1934) Secy., Frank O'Hara, , Lau Blower Co., 2665 Boston Blvd., Detroit, Inc., 4(M0-82nd St., Jackson Heights, and (for Mich. mail) 87-65-52nd Ave., Elmhurst, L. I., N. Y- LANG, Jacob (A 1938) Warm Air Htg. Technician (for mail) Lang 8c Lang, 91-48 119th St., and 91-48 Lefferts Blvd.. Richmond Hill, L. I., N. Y. LAWLOR, John J. (Af 1935) Mgr. Hearing Div., The James Robertson Co., Ltd., 215 Spadina Ave., and (for mail) 35 Tennis Cres., Toronto. Ont., Canada. LANG, J. Clifford (7 1937) Commercial Field Eagr., York Ice Machinery Corp.. 117 & 11th . St., St. Louis. Mo., and (for mail) 606 Washington PI.. East St. Louis, IH. LAWRENCE, Floyd Dwight (A 1938) Sales Engr., Clarage Fan Co. (for mail) 500 Fifth Ave., New . York, and 34-31 8lst St., Jackson Heights, L. I., N. Y. 41 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 LAWRENCE, Lewis F.i Jr. (7 1938) Field Engr. (for mail) Minneapolis-Honeywell Regulator Co., 304-101 Marietta St.,-and 1000 Greenwood Ave., N. E., Atlanta. Ga. LEACH. Leland S. (7 1937) Asst. Chief Engr., Sidles Co., Airtemp Div., Omaha, Nebr., and (for mail) 1534-9th St., Des Moines. la. LEBRUN. Paul (Af 1038) Sales Mgr., Chaudieres & Radiateurs "Ideal" S.A. (for mail) 120. rue Neuve, and 151 Boulevard Brand Whitlock. Brussels. Belgium. LEDGETT, F. Donald (7 1940; 5 1936) 108 Clinton St., Toronto, Ont., Canada. LEE, James A. (A 1937) Southeastern Com mercial Div. Mgr. Kelvinator.Div., Nash-Kelvi- nator Corp., 1426 N. Charles St., and (For mail) 1208 Argonne Drive, Baltimore, Md. '. LEE, Robert T. (7 1937; 5 1936) Instructor in Engrg. (for mail) Brown University, and 32 Manning St., Providence, R. I. LEEK, Charles W. (Af 1938) Managing Director, Leek & Co., Ltd., 1111 Homer St., and (for mail) 4682 West 6th Ave., Vancouver, B. C., Canada. LEEK, Walter {Lift Member', M 1903) Pres, (for mail) Leek & Co., Ltd., 1111 Homer St., and 4769 W. Second Ave., Vancouver, B. C:, Canada. LEFEBVRE, Eugene J. (Af 1937) Engr., Warden King, Ltd., 2104 Bennett Ave., Montreal, and (for mail) 38 Third St., St. Lambert, P. Q., Canada. , .' LEGLER, Frederick W. (Af 1935; A 1933) Pres, (for mail) The Waterbury Co., 17 W. 28th St., and 2919 Johnson St., N. E., Minneapolis, Minn, LEHMAN. M. G. (A 1937) Owner (for mail) M. G. Lehman. 720 O St.;, and 2011 Worthington, Lincoln, Nebr. . LEHMANN, Matt (A 1939; 7 1937) Engr., Mech. & Elec. Consulting, 603 Architects Bldg., and (for mail) 1569 Midvale Ave., Westwood, Los Angeles, Calif. . LEICHNITZ, Robert W. (7 1936) Asst. Mgr., Leichnitz Johnson Co., 14 E. A St., and (for mail) 2506 W. Chestnut, Yakima; Wash. ' . LEIGH, Robert L. (A 1938) Pres., Air Control Products, Inc. and (for mail) 16 W. Grand Ave., ' Muskegon, Mich. - -- LEILICH, Robert K. (Af1937) Western Mgr. (for mail) The Marley Co.. 1144 S. Grand Ave., Los Angeles,-and 1024 Tiverton Ave., West Los Angeles, Calif. : . . LEILICH, Roger L. (Af 1922)r Pres, (for mail) Wallace Stebbins Co.,, Inc., Charles & Lombard Sts., and 2810 Elsinor Ave., Baltimore. Md. LEINROTH, J. Paul (M 1929) Gen. Industrial. , Fuel Repr. (for mail) Public Service Electric & Gas Co., 80 Park Place, Newark, and 37 The Fairway, Montclair, N. J. .. . LEITCH. Arthur S. (Af 1908) Pres, and Gen. Mgr. (for mail) The Arthur S. Leitch Co., Ltd., 1123 Bay St., and 421 Russell HiU Rd., Toronto, Ont., Canada; f LEITGABEL, Kenneth-A. (S 1939) Student, University of Wisconsin, Madison, and (for mail) '9004 Jackson Park Blvd.,- Wauwatosa, Wis.- LELAND, Warren B. (Af 1929) Sales Engr. (for - mail) The H. B. Smith Co., Inc., P. O. Box 1522, and 159 Sumner Ave.. Springfield, Mass. LELAND, WHHam E. (Af 1915) Consulting Engr. (for mail) Leland & Haley, 58 Sutter St., San Francisco, and 704 The Alameda.,Berkeley.Calif. LENIHAN, William O. (A 1936) Vice-Pres., Laverack & Haines, Inc., 718 White Bldg., Buffalo. N.. Y. ; . LENONE, Jose M. (Af 1919) Designing Engr. (for mail) Wilson & Co., Inc., 4100 S. Ashland Ave., and 2048 East 69th St'.,-Chicago, III. . LEONARD, Lorcan C. G. (7 1937) Tech. Mgr., Messrs. McCann-Jeffreys,. Ltd., 19-20 Ellis's Quay, and (for mail) 265 Clontarf Rd., Dublin, Ireland. . LEONHARD, Lee W. (Af 1936) Supvr., Eastman Kodak Co., and (for mail) 1075. Winona Blvd., Rochester, N. Y. `' LEOPOLD, Charles S. (Af 1934)'Consulting Engr. (for mail) 213 S; Broad'St., Philadelphia, and 7600 West Ave., Elkins Park, Pa. LESER, Fred A. {A 1937) Dist. Mgr. (for mail) ilg Electric Ventilating Co., 608 Mills Bldg., and 4711 Chesapeake St., N. W., Washington, D. C. LEUPOLD, George L. (A 1937) Sales Engr., Min'neapoUs-HoneyweH Regulator Co., 561 Read ing Rd., and (for mail) 1715 Stonybrook Drive. Cincinnati, O. LEUTHESSER, Fred W.. Jr. (Af 1937) Secy, (for mail) National Metal Products Corp., 21 N. Loomis St., Chicago, and 1640 Wesley Ave., Berwyn, 111. . LEVENTHAL, Bernard (7 1937; S 1935) 3913 13th Ave., Brooklyn, N. Y. LEVINE, Charles (J 1939) Service Engr, (Air Cond. Dept.) Alfred L. Hart, Inc., 315 Vanderbilt Ave., and (for mail) 402 Ocean Ave., Brooklyn, N. Y. LEVY, Marlon I. (Af 1938; A 1936; 7 1931) Pres, (for mail) Viking Air Cond. Corp., 9500 Rich mond Ave.. and 3156 Ludlow Rd., Cleveland, O. LEWIS, Carroll E. (Af 1930) Gen. Sales Mgr., Delco Appliance Div., General Motors Sales Corp., 391 Lyell Ave., and (for mail) 55 Crestline Rd., Rochester, N. Y. LEWIS, Clyde A. (A 1939; 7 1937) Engr., Carrier Corp;, Marine Div., Chrysler Bldg., New York, and (for mail) 23-27-28th St., Astoria, L. I., N. Y. LEWIS, George M. (Af 1937) Chief Engr. Penob scot Bldg., Simon J. Murphy Co., 1366 Penobscot Bldg., and (for mail) 14414 Grandmont Rd., Detroit, Mich. ' LEWIS, Harry F. (7 1939) Engr., Eagle-Picher Sales Co., Temple Bar Bldg., and (for mail) 220 Atkinson. Cincinnati,-O. LEWIS, H. Frederick (A 1937) Vice-Pres. (for mail) Dwight Oil Heat, .147 Dongan Ave., Albany, and Sweet's Crossing,. Nassau, N. Y. LEWIS, J. C. (7 1938) Salesman (for mail) York Ice Machinery Corp., 5051 Santa Fe Ave.,-and ' C327-A Middleton St., Los Angeles, Calif. LEWIS, Kenneth C. (A 1938) Air Cond. Engr.. Electric Products Corp., 5624.Penn Ave., Pitts burgh, and. (for mail) 224 Emerson Ave-V Aspin- wall. Pa. ' . LEWIS, L. Logan* (Af 1918) Vice-Pres., Chief Engr. (for mail) Carrier Corp., 300 S. Geddes St., and 207 Sedgewick Drive, Syracuse, N. Y. LEWIS. Samuel R.* (Af 1905) (Presidential Member) (Pres., 1914; 2nd Vice-Pres., 1910; Board of Governors, 1909-1910-1912; Council, 1914-1915) Consulting Mech. Engr. (for mail) 407 S. Dearborn St., and 4737 Kimbark Ave., Chicago. 111. . LEWIS, Thornton* (Af 1919) (Presidential Menu ber) (Pres., 1929; 1st Vice-Pres.. 1928; 2nd Vice- Pres., 1927; Council,-1923^1930) Holiday Hill, R.`D. No. 2, Newtown, Pa. LEWIS, W. W,, Sr. (A 1939) Mgr., Htg; Refriger-. ation & Air Cond. Depts. (for mail) Beeson Hardware Co.; P. O. Box 1390, 214 N. Main Str and 604 Woodron Ave., High Point, N. C. LIBBY, Ralph SJ (A 1939; 7 1933) Air Cond. Engr. (for mail) Kosmack & Sale, 75 Government Rd., W., and 75A Government Rd., W., Kirkland Lake, Ont., Canada. ' LICANDRO, James P. (7 1938) Air Cond Engr. (for mail).Carrier Corp., 704 Statler Bldg., and 115 Peterboro St., Boston, Mass. ' - LICHTY, Charles P. (M 1920) Mgr. (for mail) C. P. Lichty Engineering Co., 400)4 S. 21st St., and 100 Devon Drive, Birmingham, Ala. LIEBERMAN, Morris S. (S 1939) Student, Carnegie Institute of Technology, Pittsburgh, and (for mail) 646 Sixth St., Oakmont; Pa. LIFSHITZ, Hymen (S 1939) Student. Carnegie Institute of Technology,, and (for mail) 2902 Webster Ave.. Pittsburgh, Pa. ' LIGHT, John C. (A 1938) Branch Mgr., Clow Gas- team Heating Co.,223WacasterSL.Jackson, Miss. LIGHTHART, Charles H. (Af 1035) Mfrs. Sales Engr. (for mail) 254 Court St,, Buffalo, and Eden, N. Y. -- - .. . LILJA, Oscar L. (A 1937; 7 1936) Mech. Engr., Toltz, King & Day, Inc., 1509 Pioneer Bldg., St. Paul, and (for mail)' 5000-.16th Ave., S,, Minneapolis, Minn. ' ' 42 ROLL OF MEMBERSHIP LINCOLN, Roland L. (Af 1935) Mgr. Dust Lab., B. F. Sturtevant Co., Hyde Park, Boston, and (for mail) 12 Lincoln St., Dedham, Mass. LINDSAY, Griffith W.t Jr. (Af 1937) 127 W. 2nd St., Xenia, O. LINEBAUGH, John E. (Af 1937) 763 Taylor St., Dayton, O. LINGEN, Ralph A. (A 1939: 7 1938) Dist. Mgr. (for mail) American Foundry & Furnace Co.,, 709 N. 11th St., and 600 N. 51st St., Milwaukee. Wis. LINGO. Charles K. (A 1936; 7 1935) Sales Engr., Florida Power & Light Co.; and (for mail) 2814 S. W. Fifth St., Miami. Fla. LINSENMEYER, Francis J. (Af 1935) Head, LONG, Edward J. (S 1939) Student, Carnegie Institute of Technology (for mail) 7 Olympia PI., Squirrel Hill, Pittsburgh, Pa., and 327 S. Douglas Ave.f Springfield. HI. LONG, Herbert P. (Af 1938) Sales Engr. (for mail) Buffalo Forge Co., 490 Broadway, Buffalo, and 336 Stillwell Ave., Kenmore. N. Y. LONG, Wayne E. (Af 1935) Prof, of Mech. Engrg., Agricultural & Mechanical College of Texas, College Station, Tex. LONGCOY, Grant B. (Af 1933) Engr., Joseph Breslove, Cons. Engr., 845 Leader Bldg., Cleve land, and (for mail) 1215 Ramona Ave.. .Lake wood, O. ........... Dept. Mech. Engrg. (for mail) University of LOO. Ping Yok (Af 1933) Gen. Mgr. (for mail) Detroit, McNichoIs & Livernois, and 17375 China Engineering Co., 30 Brenan Rd., Shanghai, Prairie Ave., Detroit, Mich. ` LINSKIE. George A. (7 1939) Htg. Engr., Gas & Heating Specialty Co., Surface Combustion Corp.. (for mail) 2nd Unit Santa Fe Bldg., and 5848 Oram St., Dallas, Tex. ' LINTON. John P. (Af 1927) Pres., Engineering Installations, Ltd., 1154 Beaver Hall Sq., and (for mail) 247 Brock Ave., N., Montreal, West, P. Q., Canada LI SCO BE, Harold W. J. (Af 1938) . Dir., Lipscombe Air Conditioning Co., Ltd., Dacre House. Victoria St., London S. W. 1, and (for mail) Glenmore, Woodland Way, West Wickham, Kent, England. LITTLE, David H. (A 1939 : 7 1937) Engr. (for mail) Boston Edison Co., 39 Boylstoi St-* Boston, and 27 Rangelev* St., Dorchester, Mass. LITTLEFORD, Wallace H. (Af 1936) Estimating Engr. (for mail) E. J. Febrey & Co., 616 New York Ave., N. W., Washington, D. C. and Hyattsville. R. F. D. No. 1, Md. LIVAR, Allen P. (Af 1935) Chief Engr. (for mail) and 271-73 Dumbarton Rd., Tientsin, China. LORE, Henry E. (7 1938) Sales Engr., Dravo Corp., Carrier Dept., 300 Penn Ave., Pittsburgh, and (for mail) 311 Chestnut St., Sewickley, Pa. LOUCKS, David W. (A 1930) Supvr.. Commercial Electric & Steam Sales (for mail) Duquesne Light Co.. 435 Sixth Ave., and 535 Shelboume Ave., (Wilkinsburg) Pittsburgh, Pa. LOUGHRAN, Patrick H., Jr. (7 1937) Industrial Engr., Washington Gas Light Co., 411-10th St., N. W., and (for mail) 4513-49th St., Washington, D. C. LOVE, Clarence H. (Af 1919) Mfrs. Agent, Nash Engineering Co., 317 Chamber of Commerce and (for mail) 289 Norwalk Ave., Buffalo, N. Y. LOVING, William H. (7 1936) Asst. Mgr.. Govt. Dept, (for mail) Washington Gas Light Co., 421-lOth St., N. W., Washington, D, C., and McLean. Va. .. LOWE, Robert A. (7 1938) Asst. Engr., Diamond Power Specialty Corp., 10340 Oakland Ave,, and Chrysler Corp., Airtemp Div., and 44 Ivanhoe " (for mail) 20436 Briarcliff Rd., Detroit, Mich. Ave., Dayton, O. LOWE, Walter (7 1940; S 1938) Salesman. LIVERMORE, James N. (Af 1939) Engr. (for Peoples Natural Gas Co., 545 Wm. Penn Way, mail) The Detroit Edison Co., 2000 Second Ave., and (for mail) 443 Althea St., Pittsburgh, Pa. Detroit, and 5 Hanover Rd., Pleasant Ridge, Mich. ; LLOYD, Edmund H. (7 1936) Asst. Mgr., Htg. Dept, (for mail) Washington Refrigeration Co., LOWNSBERY, Benjamin F. (Af 1920) Htg. Engr., Beniamin F. Shaw Co., Second and Lombard Sts., and (for mail) 21 S. Sycamore St., Wilmington. Del.- 1733-14th St.. N. W., and 2614-39th St.. N. W., Washington, D. C. - LLOYD, Edward C. (Af 1927) Dir. of Tech. Service (for mail) Armstrong Cork Co., and R. D. 5. Lancaster, Pa. ' LUCK, Alexander W.* (Life Member; Af 1919) Pres, and Gen. Mgr. (for mail) Reading Heater & Supply Co:, Church & Woodward St., Reading, and Reiffton, Pa. . LOCK, Rowland H. (Af 1939) Gen. Mgr. & Vice- LUCKE, Charles E. (Af 1924) Stevens Prof, of Pres., J. H. Lock & Sons, Ltd., 221 Sterling Rd., Mech. Engrg. (for mail) Pupin Bldg.. Columbia and (for mail) 24 Kennedy Park Rd., Toronto, University, and 186 Riverside Dr., New York, Ont., Canada. \ N. Y. . ' ' LOCKE, James S. (Af 1939) Sales Engr., Minne- apolis-Honeywell Regulator Co., 433 E. Erie St., Chicago, and (for mail) 1828 Fairview Ave., S., Park Ridge, III. .` LUDERS, Richard H: (7 1937: 5 1936) Research Engr., Quaker Oats Research Laboratory, 345 EL 25th St., and (for mail) 2410 N. Kilbourn Ave., Chicago, III. :. LOCKE. Robert A. (Af 1935) Mgr., Steel Hearing Boiler Inst., and (for mail) 500 N. Union St., Middletown, Pa. LOCKHART. Charles W. (7 1938) Sales Engr. (for mail) Buffalo Forge Co., 708 Pershing Sq. Bldg., and 625 S. Burlington Ave., Los Angeles, Calif. LOCKHART, Harold A. (A 1936; 7 1935) Chief LUND, Clarence E.* (Af 1936; 7 1935; S 1933) . . Research Engr., University of Minnesota, Engrg. ' Exper. Sta-, 108 Experimental Bldg., and (for mail) 4817-12th Ave.,. S., Minneapolis, Minn. LUTY, Donald J. (Af 1933) Asst. Gen. Mgr., Air Conditioning Div., Gar Wood Industries, Inc., 7924 Riopelle St., and (for mail) 13661 Cloverlawn Ave., Detroit, Mich. Engr., Bell & Gossett Co., 3000 Wallace St., and LYCAN, Larb K. (A 1937) 4801 Leavenworth St.. (for mail) 11747 Hale Ave:, Chicago, 111. ' Omaha, Nebr. LOCKHART, William R. (A 1939; 7 1936) Dist. Sales Mgr. (for mail) York Ice Machinery Corp., 215 Investment Bldg., and 3430-30th St., N. W., Washington, D. C. LOCKWOOD, Glenn E. (A 1938) Sales Engr. (for mail) Howard E. Melton, Inc., 207 N. W. Tenth LYFORD. Robert G. (7 1939) Sales Engr. (for mail) The Powers Regulator Co., 1634 Allen Bldg., and 4716 St. Johns Dr., Dallas, Tex. LYKE, Henry W. (Af 1938) Engr. (for mail) Peter Smith Heater Co., 6209 Hamilton Ave., and 7359 Byron Ave., Detroit, Mich. . St., and 56th and Kelly, Oklahoma City, Okla. LOEFFLER, Frank X. (Af 1914) Pres, (for mail) Loeffler-Greene Supply Co., 1604 N. W. Fifth St., and 1811 N. W. Nineteenth St., Oklahoma City, Okla. LOH, Nan-Shee (Af 1933; A 1931; 7 1927) Mgr., Ne'w Shanghai Hearing & Plumbing Co., Room 330, National Commercial Bank Bldg., 400 Kiangse Rd., Shanghai, China. LYLE, J. I.* (Af 1911) (Presidential Member) (Pres., 1917; Council, 1917-1918) Pres., Carrier . Corp., Syracuse, N. Y. . LYMAN, Samuel . (A 1924) Buensod-Stacey Air Conditioning, Inc., 60 East 42nd St., New York, N. Y., and (for mail) 865 Hueston St., Union. N.J. LYNCH, William L. (Af 1928) Pres, (for mail) Rome-Tumey Radiator Co., and 1413 N. George St., Rome, N. Y. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 LYNN, Frederick E. (Af 1938) Chief Engr.. Electric Products Corp.. 5624 Penn Ave., Pitts burgh. and (for mail) 312 Moyhend St-, Spring dale, Pa. LYNN, Richard G. (S 1938) Htg. & Air Coed. Engr., Frigidaire Div., General Motors Sales Corp., 2446 University Ave., and (for mail) 22S4 Highland Pkwy., St. Paul, Minn. LYON, P. S. (Af 1929) Pres, and Gen. Mgr. (for mail) Cochrane Corp.. 17th St. below Allegheny Ave., and 3416 Warden Drive, Philadelphia, Pa. LYONS, Cornelius J. (A 1932) Sales Engr. (for mail) Nash Engineering Co., Wilson Ave., and 5 Olmstead Place, South Norwalk, Conn. M M ABLEY, Louis C. (Af 1937) Salesman (for mail) Surface Combustion Corp., 2375 Dorr St., and 2129 Collingwood Ave., Toledo, O. MABLEY, T. HolUster (Af 1939) Chief Engr. (for mail) Mechanical Heat & Cold, Inc., 7704 Woodward Ave., Detroit, and 2323 Yorkshire Rd., Birmingham, Micb. MABON. James E. (S 1939) Student (for mail) Carnegie Institute of Technology, Pittsburgh, and 340 N. Walnut St., Blairsville, Pa. MACCUBBIN, Howard A. (Af 1934) Buyer, Montgomery Ward 8c Co., 617 W. Chicago Ave., Chicago, and (for mail) ton. 111. 1511 Colfax St., Evans ' . MACDONALD. Donald B. (Af 1930) Sales Engr., Donald B. Macdonald Co., 101 E. Walnut St., Kingston. Pa. MacDONALD, Douglas J. (Af 1935) Vice-Pres. (for mail) Standard Sanitary & Dominion Radi ator Co., Ltd., Royce & Lansdowne Ave., and 96 Hudson Drive, Toronto, Ont., Canada. MacEACHIN. Graham C. (Af 1938) DisL Engr-, Frigidaire Div., General Motors Sales Corp., Air Conditioning Dept., 2615 West 7th St., andjfor mail) 4613 El Campo Ave., Fort Worth, Tex. MacGREGOR, Cecil M. (A 1939) Sales Engr., Portland Gas & Coke Co., Public Service Bldg., and (for mail) 1842 S. E. 41st Ave., Portland, Ore. MACHEN, James T. (A 1938; J 1934) Chicago Branch Mgr. (for mail) The Ric-wiL Co., 549 W. Washington St., and 420 Diversey Pkwy., Chicago, 111. MACKEREL, Ferdinand (Af 2939) Engr., 50 Rue Daguerre, Algiers, French North Africa. MACHIN, Donald W. (J 1935) Fuel Engr.. The Pittsburgh & Midway Coal Mining` Co., 816 Dwight Bldg., Kansas City, Mo., and (for mail) 2112 Vermont St., Lawrence, Kan. MACK, Emil H. (A 1938) Asst. Sales Mgr., The Vilter Mfg. Co., 2217 S. First St., and (for mail) 2225 N. Booth St., Milwaukee. Wis. MACK, Ludwig (Af 1935) Dist. Mgr., Cooling & Air Cond. Div., B. F. Sturtevant Co., Cresmont 6 Haddon Aves., Camden, N. J., and (for mail) 412 W. Hortter St., Germantown, Philadelphia, Pa. . MacLACHLAN, Victor D. (A 1939; / 1938) Sales Engr., Minneapolis-Brown, Ltd., Wadsworth Rd., Perivale, Green/ord. Middlesex, England. MacLEAN. Hector A. (Af 1939) Prop. & Mgr. (for mail) The MacLean Plumbing Service, P. O. Box 400, and Tremoy Rd., Noranda, P. Q., Canada. MacMILLAN, Alexander R. (Af 1936) Mgr., Detroit Zone (for mail) Delco Appliance Div., General Motors Sales Corp., 306 General Motors Research Bldg., and 2455 Longfellow, Detroit, Mich. MACRAE, Robert B. (A 1939; J 1935) Engr. (for mail) E. J. Nell Co., P. O. Box 1640, Manila, and 5 Palm Court, Pasay, Rixal, P. 1. . MACROW, Lawrence (J 1936) Branch Engr.; Carrier Corp., 12 S. 12th St., Philadelphia, and (for mail) 166 S. Eagle Rd., Manoa, Upper Darby. Pa. MacWATT. Donald A, (Af 1938) Sales Engr., Powers Regulator Co., 231 East'46th St., New York, and (for mail) 4611-258th St., Grtat Neck, L. I.. N- Y. MADDEN, John J. (A 1937) Owner (for mail) The Madden Co., 339 Warren St., Roxbury, and 16 Brown Ave., Roslindale, Mass. MADDUX, O. Lloyd (Af 1935: A 1933) Owner. O. Lloyd Maddux, 53 Park Place, New York. N. Y., and (for mail) 95 Washington St., East Orange, N. J. MADELY, Frederick J. (A 1936) Chief Estimator, Eastern Steel Products, Ltd., 1335 Delorimier Ave., and (for mail) 6370 Louis-Hemon St., Montreal. P. Q., Canada. MADISON, Richard D. (M 1926) Research Engr. (for mail) Buffalo Forge Co., 490 Broadway, Buffalo, and 218 Brantwood Rd.. Snyder, N. Y. MAEHLINC. Leon S. (Af 1932) Supt.. Editable Gas Co., 6304 Penn Ave., and (for mail) 414. Sulgrave Rd., Pittsburgh, Pa. MAGEE, Kevin B. (A 1938) Engr., Cooling 8c Air Div., B. F. Sturtevant Co., Graybar Bldg., New York, and (for mail) 23-32 31st Ave., Astoria, , L. I., N. Y. MaGIRL, Willis J. (Af 1934; A 1931; J 1927) Chief Engr. (for mail) P. H. MaGirl Foundry & Furnace Works, 401-13 E. Oakland Ave., and 108 Warner Ave., Bloomington, 111. MAGNUSSON, Nicholas (A 1938). Estimator- Designer, Montgomery Ward & Co., 150-15 Jamacia Ave.. and (for mail) 138-05 Linden Blvd., Jamacia, L. I., N. Y. MAHON, B. B. (Af 1935) Principal of School of Air Cond. (for mail) c/o Rufus T. Strohm, Dean. International Correspondence Schools, and 433 Fig St., Scranton, Pa. MAHON, Clarence A. (A 1938) Pres.-Mgr. (for mail) Air Control Equipment Co., 1712 Main St., and 6123 Kenwood Ave., Kansas City, Mo. MAHON. Frank B. (Af 1937) Industrial Sales Promotion (for mail) Duquesne Light Co., 435 Sixth Ave., and 1241 Illinois Ave., Pittsburgh, Pa. MAHONEY, David J. (Af 1930; A 1926) Branch Mgr. (for mail) Johnson Service Co., 503 Franklin St., and 140 Linwood Ave., Buffalo, N. Y. MAIER, George M. (Af 1921) Mfg. Dept, (for mail) American Radiator & Standard Sanitary Corp., 8007 Jos Campau. Detroit, and 486 St. Clair, Grosse Pointe, Mich. MAIER, Herman F. (Af 1926) Chief Engr.-Secy.. The New York Blower Co., 3155 Shields Ave., and (for mail) 7124 S. Morgan St., Chicago, 111. MAILLARD, Albert L. ' (Af 1934) Consulting Engr., 5624 Cherry, Kansas City. Mo. MAKIN, Henry T,, Jr. (Af 1939) Engr. & Archt's. Repr., American Radiator & Standard Sanitary Corp., 2212 Walnut St., and (foT mail) 301 . Wadsworth Ave., Philadelphia, Pa. MALCOLM. Bernard L. (A 1939; J 1937) Engr. (for mail) Sidles Co., Airtemp Div., 502-South 19th, and 2711 Iowa St., Omaha, Nebr. MAL1N, Benjamin S- (A 1940; J 1939) Section Chief, Air Cond. Section, Bureau of Agricultural Engrg., U. S. Dept, of Agriculture, 400-11th St.. S. W. and (for mail) 4924 Butterworth Place, N. W,, Washington, D. C. MALLIS. William (Af 1914) Owner (for mail) 330 Lyon Bldg., and 723 Federal Ave., Seattle, Wash. MALLY, Chester F. (A 1938) General Mgr., Mally & Co,, 20420 Woodward Ave., and (for mail) 2034 Central Ave., Femdale, Detroit, Mich. MALONE, Dayle G. (Af 1929; A 1925) Branch Mgr. (for mail) Petroleum Heat and Power Co., 3301 S. California Ave., and 7337 Merrill Ave., Chicago, 111. MALONE, James S. (A 1936) Dist. Repft (for mail) Hoffman Specialty Co., 411 N. Tenth St., and 7124 Waterman Ave.. St. Louis. Mo. MALVIN, Ray C. (Af 1929) Pres, (for mail) Malvin & May, Inc., 2015 S. Michigan Ave., and 8220 Dante Ave., Chicago, 111. MANDELL. Thomas P. (A 1937) Sales Engr. (Air Cond.) Boston Filter Co., Inc., Harvard Square, Charlestown, and (for mail) South Hamilton, Mass. MANK, Merrill (A 1939) Owner, Merrill Mank Co., 14 Bonnefoy Place, and (for mail) 15 North Ave.. New Rochelle, N. Y. *. 44 ROLL OF MEMBERSHIP MANN, Arthur R. (Af 1930) Partner (for mail) Mann 8t Co.. Archts., 902 Wiley Bldg., and 122 W. 15th St*. Hutchinson, Kan. MANN, Walter N. (Af 1939) Gen. Mgr., Brockhouse Heater Co., Ltd., Victoria Works, West Bromwich, and (for mail) "Moneymore" Canwell, Sutton Coldfield, Warwickshire, England. MANNEN. Dion E., Jr. (J 1939) Vice-Pres., The Mannen 8c Roth Co., 9108 Woodland Ave., and (for mail) 12631 Britton Dr., Cleveland, O. MANNING, Charles E. (/ 1937) Sales Engr., Refrig, and Air Cond.. c/o Bond & Bond, -Ltd., 6-8 Commerce St., and Princess St., Auckland, New Zealand. MANNING, Walter M. (Af 1930) Traveling Engr-. Baker Mfg. Co., Omaha, and (for mail) P. O. Box 112, Clarks, Nebr. MANNY, J. Harvey (A 1936) Pres, (for mail) Robinson Furnace Co., 213 W. Hubbard St-, and 240 N. Parkside Ave., Chicago, 111. MARCHIO, Emilio, Jr. (J 1940; 5 1938) Beta Air Conditioning Corp., 1820 Wyandotte, and (for ' mail) 212 S. Monroe, Kansas City. Mo. MARCONETT, Vernon G. (A 1936) Supt., The Farquhar Furnace Co., and (for mail) Wilming ton, O. MARIN, Axel* (Af 1935) Assoc. Prof. Mech. Engrg. (for mail) University of Michigan, 241 W. Engineering Bldg., and P. O. Box 175, Ann Arbor, Mich. MARKLAND, Charles E. (Af 1939) Mech. Engr. (for mail) 110 Power Plant, University of Illinois, Urbana, and 1117 W. Williams St.. Champaign, 111. MARKS, Alexander (A 1930) Chief Engr.. Richmond Radiator Co., and (for mail) 818 Fayette Title & Trust Bldg., Uniontown, Pa. MARKUSH, Emery U. (Af 1931) Consulting Engr. (for mail) Midland Mechanical Instal lations, Inc.. 225 East 21st St., New York, and 8430-85th Rd., Woodhaven, L. I.. N. Y. MARRINER, John M. S. (M 1934) Vice-Pres(for mail) Taylor Engineering 8: Construction Co., Ltd., 80 Richmond St.. W.. and HIM Balsam Ave., Toronto, Ont., Canada. MARSCHALL, Peter J. (Af 1930; J 1927) Engr.. Kroeschell Engineering Co., 215 W. Ontario St., Chicago, and (for mail) 2009 Greenwood Ave., Wilmette, 111. MARSHALL, Albert W. (Af 1937) 714 N. St. Clair St., E. E.. Pittsburgh, Pa. MARSHALL, James v 1939) Engr., The Bahnson Co.. 1001 S. Marshall St., and (for mail) 231 S. Hawthorne Rd., Winston-Salem, N. C. MARSHALL, Orville D.. (A 1931) Mfrs. Agent (for mail) 514 Anderson - Bldg., and 1440 Fisk Rd.. S. E., Grand Rapids, Mich. MARSHALL, R. Douglas (A 1938) Partner. Delavan Engineering Co., 414 12th St.. Des Moines, la., and (for mail) 89 Park Ave., Port Washington, L. I., N. Y. MARSHALL, Stanley C. (Af 1939) Chief Engr.. Mayflower-Lewis Corp., Duluth Aye. & East 7th St., St. Paul, and (for mail) Oak Grove Hotel. Minneapolis, Minn. MARSHALL, Thomas A, (J 1937) Sales Engr. (for mail) York Ice Machinery Corp., 1275 Folsom SL, and 459 Fell St., San Frandsco, Calif. MARSHALL, William D. (Af 1935) Branch Mgr. (for tnail)Noland Co., Inc.,1823 N. Arlington Ridge Rd., and 1307 N. Wakefield SL, Arlington, Va. MARSTON, Anson D.* (A 1937) Industrial Engr.. In Charge of Air Cond. (for mail) Kansas City Power & Light Co., 1330 Baltimore, and 4943 Central, Kansas City, Mo. MARTEL, Charles L,, Jr. <7 1937) Pres., Martel . Heating Co., 13534 Cedargrove Ave., Detroit, Mich. MARTENS, Edward D. (Af 1937) Mech. Engr. (for mail) Thompson Starrett Co., Inc., 444 Madison Ave., New York, and 89 Eldridge Ave., Hempstead, L. I., N. Y. MARTIN, Albert B. (Af 1917) Chicago Branch Mgr., (for mail) Kewanee Boiler Corp., 1858 SWestern Ave., Chicago, and 997 Vine St., Winnetka, III. MARTIN, George W.* (Af 1911) Supervising Engr. (for mail) U. S. Realty 8t Improvement Co., Ill Broadway, New York, N. Y., and 340 Prospect St., Ridgewood, N. J. MARTIN* John O. (A 1939) Partner (for mail) J. O. & C. U. Martin, 637 Minna St., San Francisco, and 328 Jerome Ave., Piedmont, Calif. MARTIN, Leonard (7 1936) Sales Engr., H. L. Peiler & Co., Ltd., 620 Cathcart St., Montreal. P. Q., Canada- MARTIN, Raymond (A 1937) Sales Engr. (for mail) Vapor Car Heating Co. of Canada, Ltd., 65 Dalhousie St., Montreal, and 702 Melrose Ave., Verdun, P. Q., Canada. MARTINEZ, Juan J. (A 1939; 7 1929) Research and Rate Engr., The Mexican Light 8t Power Co., Ltd., Gante 20, and (for mail) Paseo de la Reforma 183, Mexico, D. F.. Mexico. MARTOCELLO, Joseph A. (Af 1934) Pres., Jos. A. Martocello & Co., 229 North 13th St., Phila delphia, Pa. MARTY, Edgar O. fAf 1916) Pres, and Gen. Mgr., Indian Head Anthracite, Inc., and (for mail) 2018 Elk Ave., Pottsville, Pa. MARTYN, Henry J. (A 1937) Pres, (for mail) Martyn Brothers. Inc., 911 Camp St., and 5306 Ridgedale St., Dallas, Tex. MARZOLF, Frank X. (A 1937) Sales Engr., Minneapolis-Honeywell Regulator Co.. 415 Brain- ard St., and (for mail) 15046 Mettetal, Detroit. Mich. MARZORATI, Giuseppe (Af 1938) Consulting Engr., S-i.N.C. (for mail) Giacomo Jucker, 28 Mauro Macchi. Milano, Italy. MASON, Gall C- (M 1939; A 1937) Sales Engr. (for mail) The Williamson Heater Co., 337 W. Fifth St., Cincinnati, O., and 52 Arcadia Ave., Lakeside Park, Covington, Ky. MATCHETT, James C. (Af 1923) Vice-Pres. and Gen. Mgr. (for mail) Illinois Engineering Co., Racine Ave. and 2lst St., and 9936 South Win . Chester Ave., Chicago, HI, MATHEKA, Charles R. (S 1939) Student. New York Technical Institute, 108 Fifth Ave., New York, N. Y., and (for mail) 304 Summit Ave., Union City, N. J. MATHER, Harry H. (A 1929) Industrial Pro motion (for mail) Philadelphia Electric Co., 1000 Chestnut St., Philadelphia, and 373 Lakeview Ave., Drexel Hill. Pa. MATHEWSON. Marvin E. (Af 1937) Secy, (for mail) A. M. Kinney. Inc., 1820 Carew Tower, and 2156 Alpine Place, Cincinnati. O. MATHIS. Eugene* (Af 1922) Vice-Pres. & Treas. (for mail) The New York Blower Co., 32nd St. and Shields Ave.. and 9161 & Hoyne Ave., Chicago, 111. MATHIS. Henry (Af 1921) The New York Blower Co., 32nd St., and Shields Ave., and (for mail) 10317 Oakley Ave., Chicago, 111. MATHIS, John (A 1938) Engr., Standard Furnace & Supply Co., 407 South 10th SL, and (for mail) 4241 Douglas SL, Omaha, Nebr. MATHIS, Julian W. (A 1921) The Ne* York Blower Co., 32nd and Shields Ave., Chicago, 111. MATHISON, Russell S. (A 1938) Asst. Mgr. (for mail) Weathermakers (Canada) Ltd., 593 Ade laide Sa... W.. and 44 Strathgowan Ave., Toronto, Ont.. Canada. MATOUSEK, A. G. (Af 1937) Air Cond. Engr.. York Ice Machinery Corp., 117 S. llth St., and (for mail) 1528 Locust SL, SL Louis, Mo. MATTHEWS, John E. (Af 1934) DisL Mgr., B. F. Sturtevant Co., 1102 Commerce Bldg., and (for mail) 5642 Lydia St., Kansas City. Mo. MATTINGLY, Maurice F. (A 1939) Sales Engr. (for mail) Johnson Service Co., 1355 Washington Blvd., and 8044 Drexel Ave., Chicago, 111. MATZ. George N. (Af 1938) Mech. Engr., A. Ernest D'Ambly, 901 Architects Bldg., Phila delphia, and (for mail) 649 Feme Ave., Drexel Hill. Pa. . HEATING VENTILATING AIR CONDITIONING CUIDE 1940 MAVES, George D. (A 1939) Sales Engr. (for mail) Minneapolis-Honeywell Regulator Co.. 617 Caro line. and 1603 Oakdale. Houston, Tex. MAWBY, Pensyl (Af 1934) Dist. Sales Mgr.. Lehigh Navigation Coal Co.. Inc.. 1421 Chestnut St., Philadelphia, and (for mail) Manor Apart ments, Ridley Park, Pa. MAXWELL. George W. (Af 1935; 5 1932) Engr., Keneaiy & Maxwell, Main St., and (for mail) Lower County Rd.. Harwich Port. Mass. MAXWELL, Robert S. (Af 1937) Gen. Mgr. (for mail) Bennett & Wright, Ltd., 72 Queen St., E,, and 107 Cheltenham Ave., Toronto. Ont., Canada. MAY, Arthur O. (A 1938; 7 1928) Sales Engr. (for mail) Stannard Power Equipment Co., 53 W. Jackson Blvd., and 5736 N. Bernard St., Chicago, 111. . MAY, Clarence W. (Af 1933) Consulting Engr. (for mail) 1201 Smith Tower, and 6056 4th, N.E., Seattle. Wash. MAY, Edward M. (Af 1931) Branch Mgr.. Steel Products Engineering Co., 1601 S. Michigan Ave.. Chicago, and (for mail) 848 N. Ridgeland . Ave., Oak Park, 111. MAY, George E. (Af 1933) Utilization Engr. (for mail) New Orleans Public Service, Inc., 317 Baronne St., and 2031 Short St.. New Orleans, La. MAY, James W. (Af 1938; 7 1935) Assoc- Prof, of Htg.-Vtg. (for mail) College of Engrg., University of Kentucky, and 261 Lyndhurst Place, Lexing- ton, Ky. MAY, Maxwell F. (M 1929) Secy.-Treas. (for mail) - Malvin & May, Inc., 332 S. Michigan Ave., Chicago, and Palos Park. III. MAYER, Robert L. (A 1938) Sales Engr.. Smedley ' & Mehl Co., 200 W. Montgomery Ave., Ardmore, and (for mail) 43 W. Albemarle Ave., Lansdbwne, Pa. MAYETTE, Charles E. (Af 1926) Consulting Engr., Room 1417 Graybar Bldg., 420 Lexington Ave., New York, N. Y. MAYNARD, J. Earle (M 1931) Chief Htg. Engr., American Radiator & Standard Sanitary Corp., and (for mail) 324 Fifth St., Elyria, O. MAYNE, Walter L. (Af 1937) Sales Mgr. (for ; mail) Marsh Valve Co., Brigham Rd. at 4th St., Dunkirk, and 130 Central Ave., Fredonia, N. Y. McCAFFERTY, Joseph E. (A 1937) Dist. Engr., Petroleum Heat ana Power Co., 419 Boylston St., Boston, and (for mall) 196 Manthome Rd., West Roxbury, Mass. McCAFFRAY, Charles E, (Af 1938) Chief Engr. (for mail) Wilson Air Conditioning Corp., 812 N.' ' Broad St., Philadelphia, and 426 Old Lancaster Rd., Haverford. Pa. McCAIN. H. King (Af 1939; A 1938; 7 1937) Air Cond. Engr. (for mail) Newcomb & Boyd, Cons. Engrs.. Trust Co. of Ga. Bldg-, and 28 Old Ivy Rd., Atlanta, Ga. McCANN, Frank D. (A 1939) Dist. Supvr. Air Cond. Sales (for mail) Westinghouse Electric & Mfg. Co., 150 Broadway, New York, and 378 Scarsdale Rd., Crestwood, Yonkers, N. Y. McCarthy. John J. (A 1937) Chief Engr. (for mail) Providence Public School Dept.'. 20 Sum- ` mer St., and 318 Academy Ave-, Providence. R. I. McCarthy, Thomas F. (Af 1938) Dist. Mgr. (for mail) Frigidaire Corp., 2031 S, Calumet Ave., and 6948 Calumet Ave., Chicago. 111. . McGAULEY, James H. (Af 1921) Pres, (for mail) J. H. McCauley, Inc., 6459 S. Central Ave., . Chicago, and 707 William St., River Forest, 111. McCLAIN, Clifford H. (Af 1937) Htg. Engr., Upper Darby Plumbing & Heating Co., Inc., 7127 Marshall Rd., and (for mail) 1600 Darby Rd., Brookline, Upper Darby, Pa. McCLANAHAN, Luther C. (Af 1930) Dist. Mgr. (for mail) Aerofin Corp., 603 Great National Life Bldg., and 811 S. Tyler, Dallas, Tex. McCLELLAN, James E. (Af 1922) Mgr., Chicago Office (for mail) American Blower Corp., 228 N. LaSalle St., Chicago, and 738 Marion Ave., Highland Park, 111. McCLINTOCK, Alexander, Jr. (Af 1928; 7 1920) Htg. Contractor (for mail) A. McClintock's Sons, 1937 Ridge Ave.. and Rochelle Ave., Phila delphia, Pa. * McCLINTOCK. William (Af 1935) Cons. Engr., Board of Education. 34J4 E. 12th St., and (for mail) 647 East 232nd St., New York. N. Y. McCLUNG, Tom H. (J 1939) Sales Engr., Brod & McClung. Lewis Bldg., and (for mail) 6626 N. E. Alameda, Portland, Ore. McCONACHIE, Lome L. (A 1928) Htg. and Plbg., Owner, L. L. McConachie Co., 1415 Harvard Rd., Crosse Pointe Park, Mich. McCONNER, Charles R. (A 1925; 7 1922) Gen. Sales Mgr., Clarage Fan Co., Kalamazoo, Mich. McCORMACK, Denis (Af 1933) Mgr., Air Cond. Instruments and Controls Dept, (for mail) Julien P. Friez & Sons, Inc., 4 N. Central Ave., Balti more, and Ruxton Post Office, Baltimore County, Md. McCOY, C. E. (Af 1936) Partner (for mail) Turner- McCoy, 315 W. Second St., and 3922 S. Lookout Ave., Little Rock, Ark. McCOY, Thomas F. (Af 1924) Mgr. (for mail) The Powers Regulator Co., 125 St. Botolph St.. Boston, and Glen Rd., Wellesley Farms, Mass. McCRAE, George W. (A 1936) Mech. & Htg. Engr., John McCrae Machine & Foundry Co., 77-81 William St., N., and (for mail) 51 Bond St.. Lindsay, Ont., Canada. . McCREA, Joseph B. (Af 1937) Owner. Heating & Ventilating, 3039 Coplin Ave., Detroit, Mich. McCULLOUGH. Henry G. (Af 1936) Mgr.. Commercial Dept., S. S. Fretz, Jr., Inc., 1902 Chestnut St., Philadelphia, and (for mail) 328 Glen Echo Rd.. Germantown, Philadelphia, Pa. McCULLOUGH, John L. (Af 1930) Asst. Branch Mgr., National Radiator Corp., and (for mail) 20 S. Roycroft Ave., (16) Pittsburgh, Pa. McCUNE, Byron V. (Af 1928) (for mail) 807 Yakima Ave., and 101 W. Yakima Ave., Yakima, Wash. . McDERMOTT*, John P. (7 1939) Sales Engr. (for mail) The Trane Co., 310 Postal Bldg., 3rd & Washington, and 3534 S. E. Claybourne, Port land, Ore. McDONALD, Anthony K. (A 1936) Sales Engr., Standard Oil Co. of New Jersey, 3035 Rodman St.. N. W.. Washington, D. C. McDONALD, Ivan (A 193ff) Dist. Repr. (for mail)- Minneapolis-Honeywell Regulator Co., Ltd., 44 Princess St., and Ste. 20 Gainsborough Apts., Winnipeg, Man., Canada. MCDONALD, James J. (7 1938) Sales Engr., Holland Furnace Co., 5760-12th St., and (for mail) 3974 Commonwealth Ave., Detroit, Mich, McDONALD, Thomas (A 1931) Vice-Pres-. Minneapolis-Honeywell Regulator Co,, 2747 Fourth Ave., S.. and 4619 Wooddale Ave., Minne apolis. Minn. McDONNELL, Everett N. (M 1923) Pres, (for mail) McDonnell & Miller, 400 N. Michigan Ave., and Drake Hotel, Chicago, 111. . McDONNELL, John E. (A 1936) Vice-Pres. (for mail) McDonnell & Miller, 400 N. Michigan Ave., Chicago, and 703 Judson Ave., Evanston, 111. McDOWELL, Harry L. (7 1939) Htg. Engr.. Syska & Hennessey, Consulting Engrs. (for mail) 111 Corcoran St., and 1609 Lakewood Ave., Durham, N. C. McELGIN, John W.* (A 1937; 7 1931) Limekiln and Butler Pikes, Ambler, Pa. McELHANEY. Gerald W. (A 1938; 7 1936) Air Cond. Engr. (for mail) Ohio Edison Co., Akron, and 2425 Fourth St., Cuyahoga Falls, O. McEWAN, Eugene E. (Af 1936) N. Y: Mgr. Air Cond. Div. (for mail) Frigidaire Div., General Motors Sales Corp., 224 W. 57th St., and Salis bury Hotel. 123 W. 57th St.. New York, N. Y. McGAUGHEY, Harold M. (Af 1937) Sales Mgr., Commercial Air Conditioning & Automatic Htg., Nash Kelvinator Corp., and (for mail) 300 Whit more Rd., Detroit, Mich. . ROLL OF MEMBERSHIP McGEORGE, Richard H. (Af 1927) Mgr., Htg. & Air Cond. Dept., McCord Radiator & Mfg. Co., 2587 E. Grand Blvd., and (for mail) 14565 Glastonbury Rd.. Detroit, Mich. McLOUTH. Bruce F. (Af 1936 ; 7 1934) Chief Engr., Heater Div. (for mail) Dail Steel Products Co., Lansing, and 135 Gunson, East Lansing, Mich. McGONAGLE, Arthur (Af 1932) Consulting McMAHON, Thomas W. (Af 1928) Dist. Mgr. Engr. (for mail) 1013 Fulton Bldg., Pittsburgh, and 6815 Prospect Ave., Ben Avon, Pa. McGOWN, Frederick H,, Jr. (7 1940; 5 1939) (for mail) American Blower Corp., 1711 Railway Exchange Bldg., and 6173 Waterman Blvd., SL Louis, Mo. - (for mail) The McGown Co., P. O. Box 105, and 4 Pine St., Cooperstown, N. Y. McGRAIL, Thomas E. (Af 1926) Local Repr., McMULLEN, Earl W. (Af 1938) Dir. of Research (for mailLThe Eagle-Picher Lead Co., and 626 Jaccard Place, Joplin, Mo. Canadian Sirocco Co., Ltd., 63 Sparks St., Ottawa, Ont., Canada. McILVAINE, John H.* (Af 1929) Vice-Pres. and Treas., Landwehr Heating Corp., Sixth and Cayuga Sts., Philadelphia, Pa. McINDOE. James F. (Af 1939; A 1931) Htg. Dept., Consolidated Supply Co., 139 S. W. Stark St., and (for mail) 1863 N. W. Aspen St., Portland, Ore. McINTIRE. James F. (Af 1915; A 1914) {Presi McNAMARA, William (A 1930) Mgr. (for mail) The Trane Co., 2694 University Ave., and 1355 Como Ave-, W,, St. Paul, Minn. ` McNEVIN, Joseph E. (Af 1937) Mgr. (for mail) Colorado Heating Co., 950 Cherokee St., and 225 E. Dakota Ave., Denver, Colo. MCPHERSON, William A. (M 1929) Chief, Htg.- Vtg. Div , Dept, of School Bldgs., 26 Norman St.. Boston, and (for mail) 86 Dwinnell St., West Roxbury, Mass. dential Member) (Pres., 1939; 1st Vice-Pres-. 1938; 2nd Vice-Pres., 1937; Council, 1926-1928; 1932 1939) Vice-Pres. (for mail) U. S. Radiator Corp., McQUAID, Daniel J. (Af 1934) Owner (for mail) Daniel J. McQuaid, Engineering Service, 614 Cooper Bldg., and 1565 Milwaukee St., Denver, 1056-44 Cadillac Square, P. O. Box 686, and 3261 Colo. Sherboume Rd., Detroit, Mich. McINTOSH, Fabian C. (Af 1921; 7 1917) (Coun cil, 1929-1931; 1933-1935) Branch Mgr. (for mail) . McRAE, Malcolm W. (Af 1939) Engr. (for mail) Crane Co., 4100 S. Kedzie Ave., Chicago, and 816 Fairview Ave., Park Ridge. 111. Johnson Service Co., 1238 Brighton Rd., and 3650 Perrysville Ave., Pittsburgh, Pa. McKEE, James W. (A 1938) Branch Mgr. (for MEAD, Edward A. (Af 1926) Sales Mgr. (for mall) Nash Engineering Co., South Norwalk, and 5 Thames St., Norwalk, Conn. mail) U- S. Radiator Corp., 439 N. Plankinton St., and 6713 W. Bluemound Rd., Milwaukee,Wis. McKEEMAN, Clyde A.* (Af 1936) Asst. Prof, of MEAD. Harry K. (A 1939) Mfrs. Agent (for mail) 1100 Guardian Bldg., Portland, and Jennings Lodge, Ore. Mech. Engrg. (for mail) Case School of Applied Science, Cleveland, and 1359 Lynn Park Drive, Cleveland Heights, O. McKENZIE, Murdock C.. Jr. (Af 1938) Htg. Engr., Southern California Gas Co., 810 S. MEAGHER. Arthur T. (Af 1938) Dir. and Sales Mgr., Plbg. 8c Htg. Dept., Wm. Stairs, Son & Morrow, Ltd., 174-190 Lower Water St., and (for mail) 83 Seymour St., Halifax, Nova Scotia, Canada. Flower St., and (for mail) 3806 Boyce Ave., Los Angeles. Calif. McKERLIE, Jardine (Af 1938) (for mail) Indus trial Training Systems, Ltd., 67 Carlton St., and 15 Glenarden Rd-. Toronto. Ont., Canada. McKINLEY, Carroll B. (7 1936; 5 1934) South MEDOW, Jules (7 1937) Designing Engr., Ilg Electric Ventilating Co., 2850 N. Crawford Ave,, a11n1.d (for mail) . 147 S. Springfield Ave., Chicago, MEHL, Oscar H. (7 1935) Engr. (for mail) Carrier western Dist. Mgr., General Refrigeration Corp., Beloit, Wis., and (for mail) 2923 Noble, Ft. Corp., 2022 Bryan SL, and 5631 Longview SL. Dallas, Tex. Worth, Tex. MEHNE, Carl A. (Af 1929) Htg.-Vtg. Expert, McKINNEY; Carl A. (A 1939; 7 1937) Air Cond. C. A. Mehne, Room 821, 101 Park Ave., New Engr. (for mail) United Gas Corp., and 1904 Brun St.. Houston, Tex. . York, and (for mail) 35 Livingston St., Valhalla, N. Y. ` McKINNEY, William J. (Af 1938; A 1934) Mgr., MEINHOLTZ, Herbert W. (Af 1936) (for mail) Atlanta Dist. (for mail) American Blower Corp., 716-101 Manetta St. Bldg., and 3363 Mathieson 608 Mayo Bldg.. Tulsa, and 1144H N. W. 26th St., Oklahoma City, Okla. Drive, Atlanta, a. . MEINKE, Howard G. (Af 1933) Div. Engr/ (for McKITRICK, Walter D. (Af 1936) Htg.-Vtg. Engr. .-(for mail) Mills, Rhines, Bellman' & Nordhoff, Archts. & Engrs-, 518 Jefferson Ave,, mail) Consolidated Edison Co. of New York, Inc., 4 Irving Place, New York, and 41 Harte St., Baldwin, L. I., N. Y. . and 2257 Upton Ave., Toledo, O. McKITTRICK, Percy A. (A 1934) Treas.-Gen. Mgr. (for mail) Parks-Cramer Co., 970 Main St., and 219 Blossom St., Fitchburg, Mass. McLaren, Fred S- (7 1935); Air Cond. Sales Engr. (for mail) Frigidaire Div., General Motors Sales Corp., 4436 Toulouse, and 7530 St. Charles Ave., New Orleans, La. . McLARNEY, Harry W. (Af 1933) Air Cond. Engr, (for mail) Union Electric Co. of Missouri, 315 N. 12th Blvd., and 5038 Bancroft Ave., St. Louis, Mo. ` MELLON, James T. J. (Af 1911) (Council, 1915) Pres, (for mail) Mellon Co., 4419 Ludlow SL. and 431 N. 63rd St., Philadelphia, Pa. MELONEY, Edward J. (Af 1937) Vice-Pres. (for mail) Bowers Bros. Co., 2015 Sansom St., Philadelphia, and 100 E. Stewart Ave., Laos- downe. Pa. MENDEN, Peter J. (Af 1935) Htg. Engr., W. H. Gilcher Co., and . (for mail) P. O. Box 762, Fairbanks, Alaska. MENSING, Frederick D. (Af 1920) (Treas., 1931 McLAUGHLIN, Joseph D. (A 1930; 7 1928) Htg. Contractor (for mail) Braley & McLaughlin, 166 Aborn St., and 45 Roslyn Ave., Providence, R. I. 1932) (Council, 1931-1932) Consulting Engr., Mensing & Co., 2845 Frankford Ave., Phila delphia, Pa- McLEAN, Dermid (Af 1917) Member of Firm (for MERGER, Charles F. (Af 1937) Prof. Physics (for mail) Snyder & McLean, 2308 Penobscot Bldg., mail) University of South Carolina, and 219 S. and 12651 Bitwood AvV, Detroit, Mich. Waccamaw. Columbia, S. C. McLEAN, James . (Af 1936) 520 Bigham Rd., Pittsburgh, Pa. MERENS, Seymour H. (A 1939) Vice-Pres. (for mail) Max Miller & Co., 2720 W. Chicago Ave., McLEISH, William S. (A 1932; 7 1928) Sales Engr. (for mail) The Ric-wiL Co., Room 1838, 101 Park Ave., New York, and 6446-184th St., Flushing, L. L. N. Y. McLENECAN, David W.* (Af 1933) Asst. Engr.. and 3355 Eastwood Ave., Chicago, 111. , MERLE, Aidr6 (Af 1934) Engr. (Air Cond. & Refrig.) Office of the Q. M. G., War Dept., U.S.A., and (for mail) 2145 California St., N. W., Washington. D. C. . ' Comm. Engr. Div., Air Cond. Dept, (for mail) General Electric Co., 5 Lawrence St., Bloomfield, and 73 Arlington Ave., Caldwell, N. J.- MERRILL, Carle J. (Af 1919) Treas. (for mail) C. J. Merrill. Inc., 54 St. John SL, and 15 Long fellow St., Portland, Me. 47 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 MERRILL, Frank A. (Af 1934) Consulting Engr. (for mail) Office of Hollis French, Cons. Engrs., 210 South St., Boston, and 19 Auburadale Rd., ' Marblehead, Mass. MERTZ, Walter A. (Af 1919) Secy, (for mail) Kehm Bros. Co., 51 E. Grand Ave., and 3753 N. Keeler Ave., Chicago, 111. MERWIN, GUe E. (M 1924; J 1923) Dist. Mgr., The Trane Co., 305 S. 51st St., Omaha, Nebr. METCALFE. Curtis (A 1937) Engr., House Htg. Dept., Detroit City Gas Co., and (for mail) 14433 Faust, Detroit, Mich. METZGER. H. J. (A 1937) Wheeter-Blaney Co.. 137 E. Water St., and (for mail) 706 Locust St., Kalamazoo, Mich. MEYER, Charles L. (Af 1930) L. J. Wing Mfg. Co., 154 W. 14th St., New York, and (for mail) American Welfare League, 86-60 Palo Alto Ave., Hollis. L. I.. N. Y. MEYER, Frank L. (Af 1932; J 1928) Vice-Pres.. The Meyer Furnace Co., and (for mail) 9 Cole Court, Peoria, 111. MEYER, Henry C., Jr * (Life Member: M 1898) (Council, 1915-1916) Pres, (for mail) Meyer, Strong & Jones, Inc., 101 Park Ave.. New York, N. Y- and 25 Highland Ave., Montclair, N. J. MEYER, Karl A. (Af 1938) Design Engr. (Fan) The New York Blower Co., 171 Factory St., and (for mail) 109 Woodward St- La Porte, Ind. MEYERS. John (Af 1937)-Branch Mgr. (for mail) Johnson Service Co. 300 Bond Bldg., 14th & New York Ave., N. W,, and 821 Maryland Ave., N. E- Washington, D. C. MICHAELS, M. A. (A 1939) Mgr. (for mail) Century Co., 223 S. W. 6th Ave., and 5239 N. E. Garfield Ave., Portland, Ore. MICHIE, D. Fraser (Af 1938; A 1930) Engrg. Sales Dept, (for mail) Crane, Ltd., 93 Lombard St., and 1047 Valour Rd., Winnipeg. Man.. Canada. MIDDLETON. David K. (/ 1936) Sales Engr. (for mail) Johnson Service Co., 230 E. Alexan drine, Detroit, and 1084 Beaconsfield, Grosse Points Park, Mich. MIDEKE, Joseph M. (A 1937) Vice-Pres.. Mideke Supply Co., 100 fe. Main St., and (lor mail) 2505 N. W.. 19th St.. Oklahoma City. Okla. MILENER, Eugene D. (Af 1936) Secy.. Industrial Gas Section. American Gas Association, 420 Lexington Ave., New York, N. Y. MILES, Clarence N. (A 1937) Foreman, Assembly Dept., Kohlenberger Engineering Corp., 805 S. Spadra Rd., and (for mail) Rte. 1, Box 174 A, Fullerton, Calif. MILLARD, E. L. (A 1938) Chief Engr. (for mail) A. Y. McDonald Mfg. Co., 1201 Dodge St., and 4238 Larimore Ave., Omaha, Nebr. MILLARD, Junius W. (Af 1929) 7 Tappan Rd., Wellesley, Mass. MILLEN, Ralph J. (A 1938) Estimating. and Layout Engr., Haried Home Appliance, 121 Downer Plate, and (for mail) 933 Harriett Ave.. Aurora, 111. MILLER, Archibald T. (M 1938) Mgr.. Insulation Sales, The Barrett Co., 40 Rector St., New York. N. Y,, and (for mail) 125 Godwin Ave., Ridge wood, N. J. MILLER, Bruce R. (Af 1935; A 1930) Mech. Engr., 1533 Northwest 25th St., Oklahoma City, Okla. MILLER, Chas. A. (A 1917) Salesman. The H. B. Smith Co., Inc., 36-46-33rd St,, Long Island City,- and (for mail) 2870 Marion Ave., New York. N. Y. MILLER. Charles W. (Af 1919: J 1908) Pres, (for mail) The Rado Co., 759 N. Milwaukee St., Rm. 405, Milwaukee, and R-l, Box 42, Meno monee Falls, Wis. MILLER, Edgar R. (A 1935) Chief Engr. (for . mail) Winnipeg Cold Storage. Cor. Jarvis and Salter, and P. O. Box 1384, Winnipeg, Man., Canada. ' MILLER, Floyd A. (Af 1911) Inspection Engr. (for mail) U. S. Treasury Dept., 377 U. S. Court " House, and 944 Montrose Ave., Chicago, III. MILLER, George F. (Af 1936) Owner (for mail) Geo. F. Miller Sales Engr.. 1625 K St.. N. W.. Washington. D. C., and 10204 Connecticut Ave., Kensington, Md. * MILLER. Glen (A 1937) Htg.-Vtg. Engr. (for mail) Southern Counties Gas Co., 810 S. Flower St., Los Angeles, and 3612 Roselawn Ave., Glendale, Calif. MILLER. Jack E. (J 1938) Engr. (for mail) Fairbanks. Morse & Co., 217 S. 8th St., St. Louis. Mo., and 7325 Phillips Ave., Chicago, 111. MILLER. Jacob (Af 1936) Pres, (for mail) Uni versal Heating Co., Inc., 121 St. Marks Place. New York, and 435 East 92nd St., Brooklyn. N. Y. MILLER, James E. (Af 1914; J 1912) Htg. Con tractor, 2210 Colfax St,, Evanston, IU. MILLER. Leo B. (Af 1926) (for mail) Perfex Corp., 415 W. Oklahoma Place, and 3481 N. Hackett Ave., Milwaukee. Wis. MILLER, Lorin G.* (Af 1933) Head. Mech. Engrg. Dept, (for mail) Michigan State College, and 525 Albert St., East Lansing, Mich. MILLER. Merl W. (Af 1932; / 1926) Plant Engr.. (for mail) The Trane Co., and 333 North 23rd St., LaCrosse, Wis. MILLER. Robert A.* (Af 1931) Tech. Sales Engr. (for mail) Pittsburgh Plate Glass Co., 2200 Grant Bldg., Pittsburgh, and 1211 Carlisle St.. Tarentum, Pa. MILLER, Robert E. (J 1935) Sales Engr. (for mail) American Radiator & Standard Sanitary Corp., 1344 Broadway, and 18264 Birchcrest Drive, Detroit, Mich. MILLER. Robert T. (A 1927) Chief Engr., Sales Dept, (for mail) Masonite Corp., Ill W. Wash ington St., Chicago, and 1412 Schilling t- Chicago Heights, 111. MILLER. Tolbert G. (A 1929; / 1921) Supt. and Engr., Herre Bros., Seventh and Emeralds St.. Harrisburg, and (for mail) 11 N. Second St.. Wormleysburg, Pa. MILLER. WUIlam T. (Af 1938) Prof. Htg.-Vtg. (for mail) Purdue University, and 525 Hayes St- West Lafayette. Ind. MILLHAM. Franklyn B. (Af 1937) Installation < Mgr., S. S. Fretz, Jr., Inc., 1902 Chestnut St and (for mail) 532 Ellet St.. Philadelphia, Pa. MILLIKEN, J. H.* (Af 1923) Repr. (for mail) American Air Filter Co., Inc., 228 N. LaSalle St- Chicago, and 1021 Ridge Court, Evanston. IU. MILLIS, Linn W. (Life Member: M 1918) Secy- Security Stove & Mfg. Co., 1630 Oakland, and (for mail) 3534 Wabash Ave., Kansas City, Mo. MILLS, Clarence A.* (Af 1936) Prof, of Experi mental Medicine (for mail) University of Cin cinnati, Cincinnati General Hospital, and 5046 Oberlin Blvd- Cincinnati. O. MILLS, Hartzell C. (A 1935) Salesman. Minne apolis Gas Light Co- 800 Hennepin Ave- and (for mail) 4137 Tenth Ave- S- Minneapolis. Minn. * MILLS, Rae Henry (J 1939) 1010 Arnette Ave- Durham, N. C. . MILNE, Arthur H. (Af 1938) Dir. Dept, of Bldgs- Protestant Board of School Commissioners of the City of Montreal (for mail) 3460 McTavish St and 4786 Grosvenor Ave- Montreal, P. Q- Canada. MILWARD, Robert K. (A 1920) Mgr. (for mail) U. S. Radiator Corp- 127 Campbell Ave- and 2441 Calvert Ave., Detroit, Mich. M1RABILE, J. James (A 1938) Installation & Service Mgr. (for mail) Thomas Shipley Inc- 143 Roosevelt Ave., and 14 Hill St- York, Pa. MITCHELL, Alva E. (Af 1939) Mgr. Oil Burner & Air Cond. Dept, (for mail) A. P. Woodson Co- 1313 H St- N. W.. and 5400 First St- N. W.. Washington, D. C. MITCHELL, Charles H. (M 1924) Engr- The Fels Co., 42 Union St., Portland, and (for mail) 2.5 Everett Ave., South Portland, Me. 48 ROLL OF MEMBERSHIP MITCHELL, Jack (Af 1938; J 1930) Mgr. Air . Cond. Dept, (for mail) Straus-Frank Co- and 2222 Nebraska, Houston, Tex. MITCHELL, John A. (A 1940: J 1938) Sales Engr- Air Cond. and Refrigeration Systems (for mail) 202 Waterloo Bldg- and 1301 Jefferson St- Waterioo, la. . MITCHELL, John G, (J 1937; 51936) Sales Engr. (for mail) Fairbanks, Morse & Co., 220 E. 5th St~, St. Paul, and 704 Delaware, S. E., Minneapolis, Minn. MITTENDORFF, Edward M. (Af 1932) Asst. Engr. (for mail) Sarco Co., Inc., Merchandise Mart, Chicago, and 956 Greenwood AveWinnetka, III. MODIANO, Rene (Af 1925) Managing DirCarrier Continentale, 4. Rue d'Aguesseau. Paris (8s) and (for mail) 55 Boulevard Beausejour, Paris (16s) France. MOESEL, F. Albert (A 1939) Asst. Mgr. (foT mail) W. A. Case & Son, 31 Main St- Buffalo, and 382 Argonne Drive, Kenmore, N. Y. MOFFAT, Ormond G. (A 1937) Application . Engr- Canadian . Westinghouse Co., Sanford Ave., and ffor mail) 141 George St- Hamilton, Ont- Canada. MOFFITT, Lloyd C. (A 1940; J 1937) Branch Engr. (for mail) Sidles Co., Airtemp Div- 509 S. 19th, and 3109 Mason, Omaha, Nebr. MOHN, H. Leroy*{Af 1937) Development Engr- Fitzgibbons Boiler Co- Inc., 23 E. Mercer St and (for mail) 136 E. 4th St- Oswego, N. Y. MOHRFELD, Herbert H. (,/ 1935) Air Cond. Engr. (for mail) C. P. Mohrfeld, Inc., 24 Lees Ave- Collingswood, and 131 Chestnut St- Haddonfield. N. J. MOLER, William H. (Af 1927; J 1923) Consulting Engr. (for mail) Kribs & Landauer, 404 Dallas Gas Bldg., Dallas, and R. F. D. No. 1, Irving, Tex. MOLFINO, Philip (Af 1938) Mech. Engr. (for mail) Leland & Haley. 58 Sutter St- and 125 Clayton St- San Frandsco, Calif. MOLLENBERG, Harold J. (Af 1936) Vice-Pres- MoUenberg-Betz Machinery Co., 22 Henry StBuffalo, and (for mail) 172 Westgate RdKenmore, N. Y. MOLONEY, Roger R. (M 1937) Design Engr- Dept. of Interior, Commonwealth Govt, of Aus . tralia. Canberra F. C. T- and (for mail) 26 Bonner Ave- Manley. Sydney, Australia. ` MONICK. Fred R. (A 1936) Mgr. (for .mail) Cochran-Sargent Co- 605 E. 8th St- and 1114 S. 6th Ave- Sioux Falls, S. D. MONTGOMERY, Edward G. (A 1938) Special Repr., Steel Co. of Canada, Ltd- 525 Dominion St- Montreal, and (for mail) 20 Finchley Rd., Hampstead. P. Q- Canada. MONTGOMERY, J. Russell (A 1937) Mgr., Standards and Research (for mail) Truscon Steel Co- Albert St- and 296 Granada Ave- Youngs town, O. . MONTGOMERY. Ora C. (Af 1933) Asst. Supt. of Power (for mail) New York Central Railroad, Grand Central Terminal, Room 1842, 70 East : 45th St- and 317 West 87th St- New York, N. Y. MOODY, Lawrence E. (Af 1919) Partner (for mail) Moody & Hutchison, Cons. Engrs- 1701 Architects Bldg- Philadelphia, Pa- and 237 Jefferson Ave., Haddonfield, N. J. MOON. L. Walter (Af 1915) (Council, 1933-1936) Pres, (for mail) Bradley Heating Co- 3834 Olive St- and 5863 Plymouth Ave- St. Louis, Mo. MOORE, Bill J,, Jr. (J 1937) 6203 Galiad, Dallas, Tex. MOORE, Bryant W. (A 1939) Mfrs. Repr. (for mail) 7408 S. E. 35th Ave- Portland, Ore. MOORE, Frank C. (A 1938) Canadian Mgr. (for mail) Aerofin Corp- 67 Yonge St- and 338 Mill wood Rd- Toronto, Ont- Canada. MOORE, H. Carlton* (Af 1935) Asst. Prof. Mech. Engrg. (for mail) Massachusetts Institute of Technology, Room 1-202, Cambridge, and 145 Beaumont Ave., NewtonvilJe, Mass. MOORE, H. Lee (Af 1919) (Coundl. 1927-1928) Repr. (for mail) Buffalo Forge Co.. 431 Fulton Bldg- Pittsburgh, and Flaccus Rd- Ben Avon, Pittsburgh, Pa. MOORE, Henry W. (Af 1935) Mgr. Air Cond. Engrg. Dept- The Birael Co- 305 Walnut St and (for mail) 1406 Myrtle Ave., Apt. 3, Cin cinnati, O. MOORE, Herbert S. (A 1923) Dist, Repr- Iron Fireman Mfg. Co. of Canada, Ltd- 602 King St and (for mail) 107 Clendenan Ave- Toronto, Ont., Canada. MOORE, R. Edwin (A 1928) Vice-Pres., Bell & Gossett Co- 3000 Wallace St- Chicago, and (for mail) 425 Merrill Ave- Park Ridge, IU. MOORE, Wesley R. (Af 1937) Branch Mgr. (for mail) Minneapoli9-HoneyweIl Regulator Co4501 Prospect Ave- Cleveland, and 14211 Ash- wood Rd- Shaker Heights, O. MOREHOUSE, H. Preston (Af 1933) Gen. Air Cond. Repr. (for mail) Public Service Electric & Gas Co- 80 Park Place, Newark, and 85 Halstead St., East Orange, N. J. MOREHOUSE, J. Stanley (Af 1938) Prof. Mech. Engrg., Villanova College, ViUanova, and (for mail) 102 Llandaff Rd- Upper Darby, Pa. MORGAN, Arthur S. (Af 1938) Mgr- Fess Oil Burners of Canada, Ltd- 85 King St., W., and (for mail) 156 Glenmanor Drive, Toronto, Ont., Canada. MORGAN. Glenn C. (Af 1911) Partner (for mail) Morgan-Gerrish Co- 307 Essex Bldg- 84 S. Tenth St- and 4308 Fremont Ave., S- Minne apolis, Minn. MORGAN, Robert C. (Af 1915) Pres, (for mail) Stewart A. Jellett Co- 1200 Locust St- and 314 W. Seymour St- Philadelphia. Pa. MORGAN, Robert W. (M 1938) Research Engr- Air Cond. & Commercial Refrigeration, Nash- Kelvinator Corp- and (for mail) 12739 Hubbell Ave- Detroit, Mich. MORIARTY, John M. (Af 1937) Owner (for mail) Consolidated Heating & Ventilating Co., 1709 West 8th St- Los Angeles, and 1616 Baldwin Ave., Arcadia, Calif. MORJN, A. R. (A 1938) Mgr- Refrigeration Dept., Macklanburg Brass & Copper Products, Inc111 N. W. 23rd, and (for mail) 925 S. W. 28th Oklahoma City, Okla. MORRIS, C. Raymond (Af 1921) Pres- Power & Heating Equipment Sales, Inc- 14 Burnett Place, Nutley, N. J. MORRIS. John A. (A 1939; J 1936) Htg. Dept.. James Robertson Co- Ltd- 946 William St- and (for mail) 4134 Marlowe Ave- Montreal, P. Q., Canada. MORRISON, Chester B. (Af 1931) Mgr. (for mail) York Shipley, Inc- 81 Jinkee Rd- and 347 Route Cohen, Shanghai, China. MORRISON, Walter B. (J 1939) Engr.. Htg. Dept, (for mail) Meier & Frank Co- 6th c Alder, and 1805 N. E. 27th, Portland. Ore. MORRISON. Wayne L. (A 1938) Owner (for mail) Fair Plumbing & Heating Co- 1908 Broadway St., and 3422 16th St- Great Bend, Kan. MORROW, J. DeWltt (A 1938) Secy.-Treas. and Gen, Mgr. (for mail) The Warren Co., Inc., 614 Walker Ave- and 5503 La Branch, Houston, Tex. MORSE, Clark T. (Af 1913) Pres, (for mail) American Blower Corp- 6000 Russell, and 8120 E. Jefferson, Detroit, Mich. MORSE. Floyd W. (A 1934) Vice-Pres. (for mail) Chamberlin Metal Weather Strip Co- 15 Oak St and 132 Villa St- Mt, Vernon, N. Y. MORSE. Louis S., Jr. (Af 1938: J 1936) Air Cond. Sales Engr. (for mail) VVesterhn Sc Campbell Co5924 Second Blvd- and 19480 Canterbury Rd,, ' Detroit, Mich. MORSE, Robert D. (Af 1936) Mfrs, Repr. (for mail) R. D. Morse Agency. 1534-lst Ave- S- and 4316 E. 43rd St- SeatUe, Wash. MORTON, Charles H. (A 1931) Sales Repr,, Kewanee Boiler Corp., Warren Webster & Co., 228 Ottawa Ave., N. W., and (for mail) 1106 Sherman St- S. E- Grand Rapids, Mich. - 49 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 MORTON, Harold S. (Af 1931) Sales Engr., Sutherland Air Conditioning Corp., 385 Minne sota St., St. Paul, and (for mail) 4330 Wooddale Ave., Minneapolis, Minn. MORTON, Paul S. (7 1939) Sales Engr., Auto matic Heating & Cooling Supply Co., 647 W. Lake St., and (for mail) 1362 Greenleaf Ave., Chicago. 111. . MOSES, Walter B., Jr. (7 1940; 5 1936) Student. Tulane University (for mail) 425 S. Peters St., and 1616 Dufossat St., New Orleans, La. MOSHER, Clarence H. (A 1919) C. H. Mosher Co.. 423 Ashland Ave., Buffalo, N. Y. MOSS, Edward (Af 1920) Htg.-Vtg. Engr., New York Rapid Transit Corp., 385 Flatbush Ave. Extension, Brooklyn, and (for mail) 9053- 204th St.. Hollis, L. I.. N. Y. MOTZ, O. Wayne (Af 1932) Consulting Engr., 234 Paramount Bldg., and (for mail) 2605 Briardiff, Cindnnati. O. MOULD. Delmar E. (Af 1936) Mgr. (for mail) J. W. Mould & Son. Ltd., 10642-l02nd Ave., and 8619-108 A St., Edmonton, Alta.. Canada. MOULDER, Albert W.* (Af 1917) Vice-Pres. (for mail) Grinnell Co., Inc., 260 W. Exchange St., Providence, and Barrington, Providence, R. I. MUCKLE, James (M 1939) Dept. Chief (for mail) Andersen, Meyer & Co., Ltd., Yuen Ming Yuen Rd., Box 265, and 11 Park Rd., Shanghai, China. MUELLER. HaraId C. (Af 1936; A 1930) Mgr., Contract Div. (for mail) Powers Regulator Co., 2720 Greenview Ave., Chicago, and 2720 Lawn dale Ave., Evanston. 111. MUELLER, Harold P. (Af 1936) Pres. & Treas. (for mail) L. J. Mueller Furnace Co., 2005 W. Oklahoma Ave., and 511 E. Monrouia Ave., Milwaukee, Wis. MUELLER, John E. (Af 1937) Mgr. of Com mercial Sales. West Penn Power Co.. 14 Wood St., Pittsburgh, and 570 Crystal Dr,, Mt. Lebanon, Pa. MUESSIG, James W. (Af 1938) Sales Engr., Oarage Fan. Co., Kalamazoo, Mich, (for mail) 333 N. Michigan Ave., Chicago, and 313 Edge- wood Ave., Lombard, ill. MUHLEMAN, Robert F. (A 1939) Asst. Mgr., Air Cond. Div., York Ice Machinery Corp., and 611 Company St., York, Pa. MUIRHEID, John G. (A 1940; 7 1937) Sales Engr., Baker Ice Machine Co., 2311 Hopedale Ave., Charlotte, N. C. MULCEY, Paul A.* (A 1939; 7 1938) AssL Dir., Anthracite Industries Laboratory, Primos, Dela ware Co., and (for mail) 300 Springfield Ave., Aldan. Pa. MULLEN, Thomas J., Jr. (7 1935) Dist. Mgr. (for mail) B. F. Sturtevant Co.. 832 Empire Bldg., and 1323 N. Franklin PI., Milwaukee. Wis. MUMFORD. William W. (7 1940; 5 1939) Johnson Auto Hospital, 1302 E. 3rd St., and (for mail) 1028 E. Haskell PI., Tulsa, Okla. MUNIER, Leon L. (Af 1919; 7 1915) Pres, (for mail) Wolff & Munier, Inc., 222 E. 4Jst SL, New YoTk, and 63 Columbia Ave., Hartsdale, N. Y. MUNKELT, Frederick H. (Af 1938) Vice-Pres., Dorex Air Cond. Div. (for mail) w, B. Connor Engineering Corp., 114 East 32nd St., New York, and 1388 East 24th St., Brooklyn, N. Y. MUNN, E. Fltz (Af 1935) Archt. (for mail) 1111 McArthur Bldg., and 65 Berrydale Ave., Winni peg, Man., Canada. MUNRO D. R., Jr. (7 1939) Mfra. Repr. (for mail) D. R. Munro & Son, 112 S. W. Pine St., and 2709 S. W. Buena Vista Dr., Portland, Ore. MUNRO. George A. (Af 1937) Member of Firm and Gen. Mgr., Hugh F. Munro & Sons, 2404 N. Mascher St., and (for mail) 173 W. Godfrey Ave., Philadelphia, Pa. MURDOCH, John P. (Af 1937) Pres, (for mail) John P. Murdoch Co., S. W. Cor. 30th & Oakford Sts., Philadelphia, and 735 Beechwood Drive. Beechwood, Pa. ' MURHARD, Erroll A. (Af 1939) Pres, (for mail) Muirhead & Murhard Co., 338 S. W. 9th Ave., and 2136 N. W. Upshur St., Portland, Ore. MURHARD, Kenneth R. (Af 1939) Sales (for mail) United States Radiator Corp., 630 N. W. 10th Ave., and 2154 N. W. Upshur, Portland, Ore. MURNIN, Edward A., Jr. (A 1937) Supt. of Development & Assembly, Sarco Mfg. Co., Clewel) & Itaska Sts., and (for mail) 802 Broad way, Bethlehem, Pa. ' MURPHREE, Robert L. (A 1940; 7 1936) Sales Engr., American Radiator & Standard Sanitary Corp.. P. O. Box 869, and (for mail) 1509 North ' 21st Place, Birmingham, Ala. * MURPHY, Edward T.* (Af 1915) Vice-Pres in Charge of Marketing (for mail) Carrier Corp., and 1055 James St., Syracuse, N. Y. * MURPHY. Howard C.* (Af 1923) Vice-Pres. (for mail) American Air Filter Co., Inc., 215 Central Ave., and Lightfoot Rd., Louisville, Ky. MURPHY. Joseph R. (Af 1934; A 1925) Vice- Pres. (for mail) Taco Heaters, Inc., 342 Madison Ave., New York, N. Y., and The Terrace, River side, Conn. MURPHY, William W. (Af 1930) Treas. (for mail) W. W. Murphy Co., 424 Worthington St., ana 25 Mansfield St.. Springfield, Mass. MURRAY, Hayward G. S. (7 1936) Sales Engr. Refrig. & Air Cond. Div. (for mail) Canadian Comstock Co., Ltd.; 1110 New Birks Bldg.,-and Apt. 36, 3719 de I'Oratoire, Montreal, P. Q., Canada. MURRAY, John J. (A 1938) Salesman-Vice-Pres.. Pierce Peny Co.. Ltd., 236 Congress St., Boston, and (for mail) 60 Commonwealth Park WeA, Newton Centre, Mass. MURRAY, Thomas F. (Af 1923) State Archt., and (for mail) 14 S. Lake Ave., Albany. N. Y. MURSINNA, Gilbert P. (A 1939) Htg. & Air Cond. Contractor (for mail) 411 Poplar St., and 732 Enright Ave., Cincinnati, O. MUSGRAVE, Merrill N. (A 1935) Pres., Harrison Sales Co., 314-9th Ave., N., and (for mail) 1005 East Roy St., Seattle, Wash. MYERS, George W. F. (Af 1930; A 1928; 7 1923) Myers Engineering Equipment Co., 3736 W. Pine Blvd., St. Louis, and (for mail) 476 Pasadena Ave., Webster Groves, Mo. MYLER, William M.. Jr. (Af 1937) Chief Engr., Janitrol Div. (for mail) Surface Combustion Corp., 400 Dublin Ave., and 1340 Glenn Ave., Columbus. O. MYTINGER, Kenneth L. (Af 1936) Owner, Kenneth L. Mytinger, 8 Monmouth St., Red Bank, and (for mail) 154 Lexington Ave., Fair Haven, N. J. N/ NACHMAN, George P. (Af 1938) Secy- & Treas. (for mail) Spohn Heating & Ventilating Co., 1775 E. 45th St., and 2870 Meadowbrook Blvd., Cleveland, O. NAROWETZ, Louis L., Jr, (Af 1929; A 1912) Active Head, Narowetz Heating & Ventilating Co., 1711-1717 Maypole Ave., Chicago, and 112 S. Northwest Highway, Park Ridge, 111. NASS, Arthur F. (Af 1927) Pres, (for mail) McGinness, Smith & McGinness Co.. 527. First Ave., and R. D. No. 8, Crafton, P. O., Pittsburgh, Pa; NATHAN, Perclval V. (A 1938) Chief Draftsman, Linde Canadian Ref. Co., Ltd., 355 St. Peter St., Montreal, P. Q., Canada. NEAL, James P. (A 1939) Consulting Engr. (for mail) 6729 Maple Ave., Mariemont, O. NEARINGBURG, Arthur (A 1938) Sales Engr. (for mail) Sheldons, Ltd., 1221 Bay St., and 130 Floyd Ave., Toronto, Ont., Canada. NEE, Raymond M. (Af 1936) Steam Service Engr. ' (for mail) Boston Edison Co., 39 Boylston St., Boston, and 10 Orkney Rd.. Brookline, Mass. NEILER, Samuel G. (Life Member: M 1893) Owner (for mail) Neiler, Rich & Co.. 431 S. Dearborn St., Chicago, and' 737 N. Oak Park Ave., Oak Park, 111. 50 ROLL OF MEMBERSHIP NELSON, Arthur W. (A 1936) Mgr., Brockton Oil Heat, Inc., 27 Legion Pkwy., Brockton, and ffor mail) 12 Sylvan Rd.. Sharon. Mass. NELSON, C. L. (A 1937; 7 1929) Chief Air Cond. Engr., Sears and Piou, 814 S. Vandeventer, St. Louis, and (for mail) 1015 Nolan Dr., Glendale, St. Louis Co.. Mo. '' NELSON, D. W.* (Af 1928) Assoc. Prof, of Mech. Engrg. (for mail) University of Wisconsin, Mech. Engrg. Bldg-, and 3906 Council Crest, Madison, Wis. NELSON, Edwin L. (A 1936) Engrg. Dept, (for mail) Union Ice Co., 1315 E. Seventh St., and 4313 Victoria Ave., Los Angeles, Calif- NELSON, George O. (Af 1923) Engr., Carstens Brothers, Ackley, la. NELSON, Harold M. (Af 1937) Pres, (for mail). H. M. Nelson & Co., Inc., 1223 Connecticut Ave-, and Rear 2208 Que St., N. W., Washington, D. C. NELSON, Herman W. (Af 1909) Pres. & Gen. Mgr. (for mail). Herman Nelson Corp., 1824 Third Ave.. and 2615-l2th St., Moline, 111. NELSON, Richard H. (A 1933; 7 1928) Secy.Treas., Herman Nelson Corp., 1824 Third Ave., and (for mail) I303-30th St., Moline, 111. NELSON, Roy O. (M 1938) Sales Engr. (for mail) C. H. Bevington Co.. 600 S. Michigan Ave., and 6419 N. Richmond St., Chicago, 211. NESBITT, A. J.* (Af 1921) Secy, and Treas. (for mail) John J. Nesbitt, Inc., State Rd., and Rhawn St., Philadelphia, and Rockfield Farm, Ambler, Pa. NESBITT, J. J. (Life Member; M 1923) Pres, (for mail) John J. Nesbitt, Inc., State Rd., and Rhawn St., Philadelphia, and Rockfield Farm, Ambler, Pa. , NESMITH, Oliver E. (A 1928) Engr., Williams Oil-O-Matic Heating Corp., Bell & Hanna, and . (for mail) 107 Warner, Bloomington, 111. NESS, William H. C. (Af 1931) Gen. Mgr. (for mail) Master Fan Corp., 1323 Channing St., , and 215 N. Kingsley Drive, Los Angeles, Calif. NESSELL, Clarence W. (Af 1937) Field Appli cation Engr., Minneapolis-Honeywell Regulator Co., 4501 Prospect, Cleveland, O. NESSI, Andre (Af 1930) Ingr. des Arts et Mfrs., " Expert pres le Tribunal Civil de la Seine (for mail) 1 Avenue du President Wilson, Paris, XVI, France. NEST, Richard E. (Af 1936) Consultant, 5018 Morello Rd.. Baltimore, Md. - NEU, Henri J. E. (Af 1933) Pres., Etablissements Neu, 47-49 Rue Fourier, Lille (Nord) France. NEUBAUER, Edwin W. (Af 1939) Engr. (for mail) Campbell Norquist& Co.. 1127 S. W. Morrison St., and 4804 N. E. Davis St., Portland, Ore. NEWCOMB, Lionel B. (A 1936; 7 1933) Junior . Engr., Philadelphia Electric Co., and (for mail) 6056 Walton Ave.. Philadelphia, Pa. NEWMAN. Harold E. (Af 1938) Asst. Mgr. (for mail) B. A. Newman Co., Box 978, and 419 Buckingham Way, Fresno, Calif. NEWPORT, Charles F.* {Life Member; M 1906) Sales Engr., Weil-McLain Co., Michigan City, Ind., and (for mail) 10001 Longwood Drive, Chicago, 111. NEWTON, Alwln B.* (Af 1938) Development Engr. (for mail) Minneapolis-Honeywell Regu lator Co., 2747-4th Ave., S., and 18 W. Rustic Lodge Ave., Minneapolis, Minn. NICHOLLS, John M. (Af 1939) Mgr. Htg. Dept., Robbins Gamwell Corp., 68 West St., and (for mail) 17 Buel St., Pittsfield, Mass. NICHOLLS, Percy* (Af 1920) Supervising Engr., Fuels Section (for mail) Bureau of Mines, 4800 Forbes St., and 5251 Forbes St., Pittsburgh, Pa. NICKLE. Arthur J. (A 1936) Sales Engr. (for . mail) Darling Brothers, Ltd.. 140 Prince St., and 4356 MardI Ave., Montreal, P. Q.. Canada. NICOLL, Scott F. (Af 1939) Air Cond. Application Engr. (for mail) York Ice Machinery Corp., and 1433 First Ave., Elmwood, York, Pa. NIELSEN, Howard B. (A 1939) Mfrs. Repr. (for mail) 409 Couch Bldg., and 5004 N. E. Wisteria Drive. Portland, Ore. NIESSE, Joe H. (Af 1937) Indiana Dist. Mgr. (for mall) Ug Electric Ventilating Co., 836 Architects & Builders Bldg., and 5837 Winthrop Ave., Indianapolis, Ind. NIGHTINGALE, George F. (A 1931) Western Sales Mgr. (for mail) Tuttle & Bailey, Inc., 01 W. Kinzie St., Chicago, and 1125 Schneider St., Oak Park, 111. NININGER, Christian H. (A 1938) Sales Engr. (for mail) Frigidaire Div., General Motors Sales Corp., Franklin Rd., and Box 198, Route 1, Roanoke, Va. NOBBS, Walter W. (Af 1919) Consulting Engr., 26 Victoria St., London, S. W. 1, and (for mail) 50 Fairhazei Gardens, London. N. W. 6. England. NOBIS, H. M. (Af 1914) Pres, (for mail) Harry Nobis Co., 305 Caxton Bldg., Cleveland, and 1827 Stanwood Rd., East Cleveland, O. NOBLE, James P. (A 1937) Mgr., The Refriger ation & Htg. Co.. 1713 Maiden Lane, and (for mail) 1512 Maiden Lane, Springfield, O. NOLAN, James J,, Jr. (Af 1939) Air Cond. Engr., United Clay Products Co., Washington, D. C., and (for mail) 5514 Johnson Ave.. Bethesda, Md. NOLAN. Ralph E. (A 1938) Owner. Ralph Nolan, Mfrs. Repr. (for mail) 429 Citizens & Southern Natl. Bank Bldg., and 3384 Mathieson Rd., N. E., Atlanta, Ga. NOLL, William F. (Af 1924) Htg. and Vtg. Contractor (for mail) 629 North 27th St., and- 2850 North 47th St., Milwaukee, Wis. NORAIR, Henry (Af 1938) Pres, (for mail) Norair Engineering Corp., U24-22nd St., N. W., and 5908-32nd St., N. W., Washington, D. C. NORBY, Karl H. (A 1938) Mgr. Htg. Dept, (for mail) Tacoma Plumbing Supply Co., 315 S. 23rd St., and 1316 S. 25th St., Tacoma, Wash. NORDINE, L. F. (Af 1914) Mgr., Washington Office (for mail) Trane Co., 1772 Columbia Rd., N. W.. Washington, D. C., and 812 Silver Spring ` Ave., Silver Spring, Md. ' NORFOLK, Leslie W. (7 1939) Consulting Engr. (for mail) E. G. Phillips. Son & Norfolk, 26 Annesley Grove, and 42 Hampden St.. Notting ham, England. NORMAN, Roy A. (Af 1937) Prof, of Mech. Engrg., Iowa State College, Mech. Engrg. Dept., and (for mail) 715 Ridgewood Rd., Ames, la. NORR1NGTON, Walter L. (7 1938) Sales Engr., The V. D Anderson Co.. 1935 W. 96th St., Cleveland, and (for mail) 1280 Cranford Ave., Lakewood. O. NORRIS, William P. (7 1938) Sales Engr., Nation & Co., 3920 Lindell Blvd., and (for mail) 410 N. Newstead Ave., St. Louis, Mo. NOTTBERG, Gustav (A 1933) Vice-Pres. (for mail) U. S. Engineering Co., 914 Campbell St., and 1835 East 68th St. Terrace, Kansas City, Mo. NOTTBERG. Henry (Af 1919) Pres, (for mail) U. S. Engineering Co., 914 Campbell St., and 150 West 54th St., Kansas City. Mo. NOTTBERG, Henry, Jr. (7 1937) Secy, (for mail) U. S. Engineering Co.. 914 Campbell St., and 150 West 54th St., Kansas City, Mo. NOVOTNEY. T. A. (Af 1928) Mgr.. Convector Div., National Radiator Corp., 221 Central Ave., and (for mail) 839 Luzerne St.. Johnstown, Pa. NOWITZKY, Herman S. (A 1931) Supt. Con struction Maintenance and Repairs, Wilmer and Vincent Theatres, 1776 Broadway, New York, N. Y.,and (for mail) 821 Llewellyn Ave.. Norfolk, Va. NOYES, Richard R. (7 193-8> Sales Engr. (for main Canadian Sirocco Co., Ltd., 630 Dorchester St., W., and 2010 Mansfield, Apt. 12, Montreal, P. Q., Canada. . NUSBAUM, Lee* (Af 1915) Owner (for mail) Pennsylvania Engineering Co., 1119-21 N. Howard St., and 315 Carpenter Lane. German town. Philadelphia, Pa. NUTTING. H. G. D. (Af 1938) Consulting Engr., 604 Donovan Bldg., and (for mail) 1461 Calvert Ave.. Detroit, Mich. NYE, L. Bert, Jr. (7 1936) Htg. Engr.. Washing ton Gas Light Co., 411 Tenth St., N. W., Wash ington. D. C.. and (for mail) 309 Piedmont St., Arlington, Va. 51 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 O OAKLEY, Le Roy W. (Af 1937) Owner-Sales Engr. (for mail) L. S. Oakley Sales Co., 408 W. Clinch Ave., and 2003 Laurel Ave., Knoxville, Tenn. OAKS, Orion O. (Af 1917) 119 Oakridge Ave., ` Summit, N. J. O'BANNON, L. S.* (Af 1928) Research Engr., Agr. Exp. Station (for mail) University of Kentucky, and 123 State St., Lexington, Ky. OBERG, H. C. (A 1933) Mgr., Engrg. Dept., Crane Co. of Minnesota. Fifth and Broadway, and (for mail) 1362 W. Minnehaha St., St. Paul, Minn. OBERSCHULTE, Richard H. (7 1938) Sales Engr. (for mail) D. T. Randall Co., 404 Boule vard Bldg., 7310 Woodward, and 13999 Mark Twain Ave., Detroit, Mich. O'CONNELL, Presly M. (Af 1916) 6749-31st Ave., N. E., Seattle, Wash. O'DOWER, Hugh J. (A 1938) Sales Engr., VUter Manufacturing Co.,-Milwaukee, Wis., and (for mail) 114 W. Tenth St., Kansas City, Mo. ODUM, Ralph A. (A 1939) Plbg. & Htg. Contrac tor, Atlee Rd., Mechanicsville, Va. OELGOETZ, J. F. (A/ 1938) Sole Owner (for mail) J. F. Oelgoetz Co.. 3365 N. High St., and 279 E. North Broadway, Columbus, O. OERTEL, Fritz H. E. (Af 1939) Consulting Engr., ; R. F. D. 2, Greensboro. N. C. . OFFEN, Ben (Af 1928) Owner (for mall) B. Offen & Co., 608 S. Dearborn St., and 3740 N. Lake Shore Dr., Chicago, 111. OFFNER, Alfred J. (M 1922) (Treas., 1935-1938; Council. 1935-1939) Consulting Engr. (for mail) 139 E. 53rd St.. New York, and 160-15-11th Ave., Beechhurst, L. I., N. Y. O'FLAHERTY, John G. (Af 1937) Chief Engr., Unifin Tube Co., 1109 York St., and (for mail) 290 Central Ave., London, Ont., Canada. O'GORMAN, J. S. (A 1934) Mgr. Detroit Office (for mail) Johnson Service Co., 230 E. Alexaiv. drine, Detroit, and 147 Abbey Rd., Birmingham, Mich. . OKE. William C. (Af 1938; 7 1934) Air Cond. Engr. (for mail) Weathermakers (Can.) Ltd., 593 Adelaide St., W., and 460 Merton St., Toronto, Ont., Canada. OLCHOFF, Maurice (M 1933) Pres, (for mail) States Engineering Co.. 923 Walnut and 501 56th St., Des Moines. Ia. - OLD. William H. (Af 1937) Asst. Mgr. (for mail) Glanz & Killian Co., 1761 Forest Ave., W., Detroit, and 18245 Devonshire Rd., R. F. D. No. 3, Birmingham, Mich. OLDES, Willard E. A. E. (A 1939; 7 1936) De signer, Standard Oil Co., Elizabeth, N. J., and (for mail) 650 West 204th St,, New York, N. Y. OLSEN, Carlton F. (A 1925; 7 1920) Kewanee Boiler Corp., 1858 S. Western Ave., and (for mail) 1836 W. 105th SL. Chicago, 1U. OLSEN, Gustav E. (Af 1930) Vice-Pres. & Sates Mgr., Fitzgjbbons Boiler Co., Inc., 101 Park Ave.. New York, and (for mail) 68-09 Amstel Blvd., Arverne, L. I., N. Y. OLSON, Bernhard (A 1929) Pres, (for mail) Barney Olson, Inc., 122 S. Michigan Ave., and 5724 N. Natoma Ave., Chicago, 111. OLSON, Gilbert E. (Af 1930) Chief Engr. (for mail) Kelley Manufacturing Co., and 8359 Park Place Blvd., Houston, Tex. OLSON, Milton J. (7 1937) Vice-Pres.. Olson Bros., 2612 Leavenworth St., and (for mail) 5627 Williams St., Omaha, Nebr. OLSON, Robert G. (Af 1923) Eastern Mgr. (for mail) Hydraulic Coupling Dv.t American Blower Corp., 50 West 40th St., and 22 East 38th St.. New York. N. Y. OLVANY, William J. (Af 1912) Pres, (for mail) Wm. J. Olvany, Inc., 100 Charles St., New York, and 109-40-71st Rd., Forest Hills, L. I., N. Y. O'NEILL, J. W. (Af 1929; A 1927; J 1925) Chief Engr., Trane Co. of Canada, Ltd., 4 Mowat Ave., and (for mail) 8 Springmount Ave., Toronto, Ont., Canada. OONK, William J. (Af 1937) Dist. Mgr., B. F. Sturtevant Co., 915 Olive St,, and (for mail) 4548 Redbud Ave., St. Louis, Mo. OOSTEN, Louis S. (7 1938) Sales Engr., Bell & Gossett Co., 3000 S. Wallace St, and (for mail) 114 E. Kensington Ave., Chicago, III. ` OPPERMAN, Everett F. (A 1940; J 1935; 51933) Estimator, Frederick Opperman. Railroad vAve., Greenwich, and (for mail) 51 Plymouth Rd., Stamford, Conn. O'REAR, Lawrence R. (Af 1934) Pres, (for mail) Midwest Plumbing & Heating Co., 2450 Blake St., and 3033 West 37th Ave., Denver, Colo. ORGAN, Frederick (Af 1939) Archt. & Engr. (for mail) 3724 Mason St, Omaha, Nebr. O'ROURKE, Hugh D., Jr. (7 1937; S 1936) 109 Webb Ave., Detroit, Mich. ORR, George M. (Af 1936) Pres, (for mail) G. M. Orr & Co..-542 Baker Arcade Bldg., and 2223 Emerson Ave., N., Minneapolis, Minn. ORR, Leighton* (Af 1937) Research Engr., Pitts burgh Plate Glass Co.. Research Laboratory, Creighton, and (for mail) 1116 Cambridge St., Tarentum, Pa. ORTIZ, Joseph V. (A 1938) c/o Steele, 2180 Bronx Park, E., New York, N. Y. OSBERGER, Thomas L. (A 1937) Mgr. (for mail) American Radiator & Standard Sanitary Corp., 90 Market St, S. W., and 918 Orchard Drive. Grand Rapids, Mich. OSBORN, Wallace J. (A 1927) Vice-Pres.. Keeney Publishing Co., Grand Central Terminal Bldg., New York. N. Y., and (for mall) 599 Old Post Rd., Fairfield, Conn. OSBORNE, G. H. (Af 1922) Managing Dir.. The Ventilating & Blow Pipe Co., Ltd., 714 St. Maurice St., and (for mail) 836 Pratt Ave.. Outremont, Montreal, P. Q., Canada. OSBORNE. Stanley R. (Af 1939) Dist Mgr. (for mail) B. F. Sturtevant Co., 220 Delaware Ave., and 27 E. Morris Ave., Buffalo, N. Y. OSTDAHL, Harold E. (7 1940; 5 1939) Engr., Minneapolis Gas Light Co., 800 Hennepin Ave., and (for mail) 712-4th St., S. E., Minneapolis, Minn. OSTROM, Eric W. (Af 1937) Chief Engr., Air Cond. Dept, A/B Svenska Flaktfabriken, Kungs- gatan, 16 and (for mail) John Ericssonagatan 18, Stockholm, Sweden. -' OTT, Oran W. (Af 1925) (Council, 2934-1936) Consulting Mech. Engr. (for mail) 606 Wash ington Bldg., and 123 S. Virgil Ave., Los Angeles, Calif. OURUSOFF, Leon* (Af 1931) Engr. of Utilization (for mail) Washington Gas Light Co.. 411-10th . St., N. W., Washington, D. C7, and 21 Cedar Pkwy., Chevy Chase, Md. OUWENEEL, William A. (Af 1937) Chief Engr., Standard Distributing Corp.. 406 E. Wells St., Milwaukee, and (for mail) 801 Marshall Ave., South Milwaukee, Wis. OVERTON. Sidney H. (Af 1929) Repr.. N. V. Radiatoren, Amsterdam, Holland, and (for mail) P. O. Box 5985, Johannesburg, South Africa. OWEN, Jeff D. (Af 1937) United States Engineers. 741 Figuera St., Los Angeles, and (for mail) 4070 East Blvd., Culver City, Calif. P PABST. Charles S. (Af 1934) Pres., Pabst Air Conditioning Corp., 55 W. 42nd St, New York,. and (for mail) 8727-98th St., Woodhaven, L. 1., N. Y. PAETZ, H. E. (Af 1922) Div. Sales Mgr., American Blower Corp., 632 Fisher Bldg., and (for mail) 1415 Parker, Detroit. Mich. PAGE, Arvin (Af 1935) Chief Engr. (for mail) The Bahnson Co., 1001 S. Marshall St., and 752 Oaklawn Ave., Winston-Salem, N. C. PAGE, H. W. (Af 1923) Pres, (for mail) Wisconsin Equipment Co., 918 N. Fourth St, Milwaukee, and 7927 Warren Ave.. Wauwatosa, Wis. 52 ROLL OF MEMBERSHIP PAGE, Vernon C. (A 1936) Mgr., Air Cond. Div. PATTERSON, James D. (A 1939) Househeating (for mail) Fftzgibbons Boiler Co., Inc., 101 Park Engr., Chattanooga Gas Co., 811 Broad St., and Ave., New York, and Colchester Hall, Scarsdale, N. Y. (for mail) 220 Signal View St.. Chattanooga, Tenn. PAINTER, David H. (Af 1924) Mfrs. Agent. PAUL, Donald I. (Af 1936; 7 1932) Sales Engr. Hoffman Specialty Co., and (for mail) 7331 Brooklyn St., Kansas City, Mo. (for mail) Gurney Foundry Co., Ltd., 4 Junction Rd.. and 408 Bayview Ave., Toronto, Ont., PAQUET, Jean*Marie (A 1940; 7 1936) Engr., Canada. J. A. Y. Bouchard, Ltd., 97 Cote d'Abraham, and PAULING, Robert E. (A 1936) Salesman and (for mail) 7 Ave. Belvedere, Apt 2, Quebec. P. Q., Canada. Repr., Illinois Malleable Iron Co., 1801 Diversey Pkwy., Chicago, 1U., and (for mail) 211 S. Gary PARENT, Harold M. (Af 1938) Partner (for mail) Ave.. Tulsa. Okla. Parent & Kirkbride, 1715 Rittenhouse St., Phila PAVEY, Charles A. (Af 1937) Dist. Mgr. (for mail) delphia, Pa., and 324 Pitman Ave., Pitman, N. J. B. F. Sturtevant Co., 812 Michigan Theatre PARK, Harold E. (A 1938; 7 1936) Sales Engr. - Bldg., Detroit, Mich., and Hyde Park, Boston, (for mail) Shaw-Perkins Mfg. Co.. 1043 Oliver Mass. Bldg., Pittsburgh, and Glenshaw Ave., Glenshaw. Pa. PAWKETT, Lawrence S. (A 1938) Mfrs, Repr. (for mail) L. S. Pawkett & Co., Insurance Bldg., PARK, J. Frank (Af 1937; A 1936; 7 1930) Sales Engr. (for mail) Western Air & Refrigeration, and 131 North Drive, San Antonio. Tex. PEACOCK, Glenn S. (Af 1939) Bldgs. & Grounds Inc., 1234 S. Grand, and 2160 Kenilworth Ave., Los Angeles, Calif. Dept., University of Pittsburgh, Oakland P. Oand (for mail) 66 Craftmont Ave., Pittsburgh, Pa. PARK, Nicholas W. (Af 1936) Htg. Engr., Phila- PEART, Alien M. (A 1937) Dist. Mgr. (for mail) ' delphia Saving Fund Society (Real Estate Minneapolis-Honeywell Regulator Co., 637 Craig Dept.) 12 South 12th St, Philadelphia, and (for mail) 509 Jericho Rd., Abington, Pa. West, Room 812, and 4635 Melrose, Montreal, P. Q., Canada. PARKER, Dudley F. (Af 1930) Sales Engr. (for mail) Nash Engineering Co.. 420 Lexington Ave., New York, ana Morristown, N. J. PARKER, Loyd L. (A 1938) Partner, Gas Appli ance Co. (for mail) 403-34th St., N. E., Washing ton, D. C. PECK, Henry E- (A 1938) Div. Mgr.. Delco Appliance Div.. General Motors Sales Corp.. 840 N. Michigan Ave., Chicago, III., and (for mail) LaSalle Hotel, 729 N. Eleventh St., Mil waukee, Wis. PEEBLES, J. K., Jr. (A 1925; 7 1924) Archi- PARKER, Paul E. (A Trane Co.. Plaza Bldg., 1938) Sales 635 N. Penn Engr., The St., Indian _. apolis, Ind. tecturaJ Engr., Baskervill & Son, Archts., Central Natl. Bank Bldg., and (for mail) 1708 Park Ave-, Richmond, Va. PARKER, Philip (Af 1915) Thermal Engineering Co., 716 Columbus Ave., Boston, and (for mail) 8 Middle St., Woburn, Mass. PARKER, Richard A. (A 1938) Secy.-Treas. (for mail) Parker-Carpenter. Inc.. 991 Bryant St., and 1464 Francisco St, San Francisco, Calif. PEISER, Maurice B. (7 1937) Sales Engr. (for mail) Natkin & Co., 1729 Howard St., Omaha. Nebr., and 22 Carter Lake Club, Carter Lake, la. PELLEGRINI, Louis C. (Af 1939) Vice-Pres.. Mario Coil Co., 6135 Manchester Ave., and (for mail) 6549 Murdoch St., St. Louis. Mo. PARKS, Charles E. (Af 1937) Dist Mgr. (for mail) Iig Electric Ventilating Co.. 805 Professional PELLER, Leonard (7 1934) 1359 N. Wells St.. Chicago. 111. Bldg., Pittsburgh, and 284 W. Steuben St., Crafton, Pa. PELLMOUNTER, Thomas (A 1936) Mfrs- Agent, Johoson-Pellmounter, 903 McGee St., and (for PARRILLI, Roberto (Af 1938) Tech. Repr. for mail) 3308 Euclid Ave., Kansas City, Mo. Europe, Nash- Kelvinator Corp., via Colonnetta 2, Milan, Italy. . PELLMOUNTER. Thomas V. (7 1938) Engr.. Cooling Coil Sales Dept, (for mail) The Trane PARROTT, Lyle G. (Af 1922) Consulting Engr.. Snyder & McLean, 2308 Penobscot Bldg., and (for mail) 3788 Gladstone, Detroit, Mich. Co'., and 401 S. 14th St.. La Crosse. Wis. PELOUZE, Henry L., II (A 1934) Mgr.-Owner (for mail) Pelouze Sales Co.. 311 Grace American PARSONS. Leonard D.. Jr. (7 1937; S 1936) Combustion Engr., Sears Roebuck & Co., Bldg., and 4209 Grove Ave., Richmond, Va. PELTZMAN, Joseph L. (7 1939) Htg. & Vtg- Technical Lab., Dept 817. Homan & Arthington ' Sts., Chicago, and (for mail) 795 Park Blvd.. Glen Ellyn, 11). Engr.. E. K. Campbell Heating Co.. 2445 Charlotte St., and (for mail) 1 E. 54th St.. Kansas City. Mo. PARSONS, Roger A. (7 1933) Htg. Engr. (for mail) Board of Water & Electric Light Com PENNEY, Gaylord W. (Af 1938) Research Engr. (for mail) Westinghouse Electric & Mfg. Co.. E. missioners, 114-16 W. Ottawa, and 2609 Clifton St.. Lansing, Midi. Pittsburgh, and 171 Orchard Rd., Wilkinsburg, Pa. PARTLAN, James W. (Life Member; Af 1916) PENNOCK, William B. (Af 1927) Sales Engr., 14290 Goddard Ave.. Detroit, Mich. Pennock Engineering, 63 Sparks St., and (for PARVIS, Ralph S. (Af 1938) Engr., Diamond Ice Sc Coal Co., 827 Market St., and (for mail) 602 McLane St., Wilmington, Del. PASSUR, Norman A. (Af 1938) Air Cond. Engr., Southern Pacific Co. (Railroad) 65 Market St., mail) 326 Waverly St., Ottawa, Ont.. Canada. PERKINS, Robert C. (A 1935) Mgr.. Dallas Office (for mail) Ilg Electric Ventilating Co-, 1115 Mercantile Bldg., and 2756 Catherine St., Dallas, Tex. San Francisco, and (for mail) 2253-39th Ave.,. Oakland, Calif. PERRAS. George E. (Af 1936) Mgr. Htg. Div. (for mail) Thomas Robertson & Co., Ltd., 262 Craig PASTOR, John C. (Af 1938) Mfrs. Repr. & Designer, 1091 Talbot Ave., Jacksonville, Fla. SL, West, and 5915 Christophe Colomb St.. Montreal, P. Q., Canada. ' PATERSON. Frederick C., Jr. (Af 1936; 7 1928) Pres., F. C. Paterson & Co., Inc., and (for mail) 70 Stone Ave., Bradford. Pa. . PERSSON, N. Bert (Af 1937) Consulting Engr., Food Service Equipment Engr., 1418 Simpson Ave., St. Paul, Minn. PATORNO, Sullivan A. S. (Af 1923) Owner. PESTERFIELD, C. H. (Af 1938; 7 1936; 5 1932) Sullivan A. S. Patomo, Cons. Engrs., 101 Park Ave., New York, N. Y. PATRICK, Horace M. (Af 1936; 7 1929) Engr., Asst. Prof, (for mail) Michigan State College Dept, of M. E., and 142 Gunson St., East Lansing, Mich. 21 Central Ave., Newark, N. J. ' PETERSEN, Christian P. (A 1937) Owner (for PATTERSON, Frank H. (Af 1936) Sales. Hoffman Specialty Co., and (for mail) 9201 Boleyn, Detroit, Mich. PATTERSON, Granville P. (Af 1939) Air Cond. mail) Petersen Sheet Metal Works, 4120 Cedar Ave., and 3914 Cedar Ave., Minneapolis, Minn. PETERSON, Carl M. F.* (Af 1936) Instructor in Mech. Engrg., Asst. Supt. of Bldgs. & Power (for 8c Htg. Contractor, W. H. Sullivan Co. (for mail) P. O. Box 232, and 200 S. Mendenhall St., Greensboro. N. C. mail) Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, and 40 Fletcher Rd., Woburn, Mass. 53 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 PETERSON, Clarence L. (Af 1938) Branch Mgr., Minneapolis-Honeywell Regulator Co., 1136 Howard St., San Francisco, and (for mall) 2 Indian Rock Path, Berkeley, Calif. PETERSON, Hans P. (7 1939) Engr. (for mail) Bush Mfg. Co., 100 Wellington St., and 224 S. Whitney St., Hartford, Conn. PETERSON, Neil H. (Af 1937) Mgr. (for mail) The Trane Co., 1129 Folsom St., and 2744 Green St., San Frandsco, Calif. PETERSON, S. D. (A 1930) N. W. Mgr. (for mail) Johnson Service Co., 514 Colmon Bldg., and 5051 Prince St., Seattle, Wash. PETIGROW, Ben N. (Af 1939) Engr. (Carrier Distributor) (for mail) P. O. Box 872, Tel Aviv, Palestine. PETTIT, Ernest N., Jr. (Af 1937) Air Cond. Engr. (for mail) United Gas Corp., United Gas Bldg., and 2930 Quenby, Houston. Tex. PETTY, Charles E. (A 1939) Sales Engr., U. S. Radiator Corp., Detroit, Mich, (for mail) Box 1301, and 2120 Providence Rd., Charlotte, N. C. PEXTON, Frank S. (A 1936) Sales Engr. (for mail) Kansas City Gas Co., 824 Grand, and 43 West 73rd Terrace, Kansas City, Mo. PFEIFFER, Frank F. (Af 1938) Engr., Service Equip. Div., United Engineers & Constructors, Inc., 1401 Arch St., and (for mail) 7421 Sommers - Rd,, Philadelphia. Pa. PFRIEM, Peter G. (A 1937) Sales Engr.,-The Knapp Supply Co., Ohio and Dudley Sts., and (for mail) 211 N. Hackley St., Muntie, Ind. PFUHLER, John L. (A 1925; 7 1923) Owner. John L. Pfuhler, Plumbing & Heating. 600 Manor Rd., W. New Brighton, S. I., N. Y. PHILIP, William (Af 1937) Sales Engr., Dominion Radiator & Boiler Co.. Ltd., Royce & Lansdowne Aves., and (for mail) 74 Bastedo Ave., Toronto, Ont., Canada. PHILIPPI, Joseph J. (Af 1939) Sales Engr. (for mail) Johnson Service Co., 1355 Washington Blvd., and 8241 S. Marshfield, Chicago, 111. PHILLIPS. F. W. (Af 1921) Htg. & Vtg. Engr.. Queens Borough Gas & Elec. Co., 1610 Far Rockaway Blvd., Far Rockaway, L. I., and (for mail) 825 E. 38th St., Brooklyn. N. Y. PHILLIPS, Ralph E. (Af 1936) ConsulUng Mech. & Elec. Engr. (for mail) Ralph E. Phillips, 816 W. Fifth St., Room 603. and 5153 Angeles Vista Blvd., Los Angeles, Calif. PHILLIPS, Robert H. (7 1938) Engr., Carrier Corp. (for mail) 1500 S. Santa Fe, and 2343 London St., Los Angeles, Calif. PHILLIPS, Walter L. (A 1938) Mgr., Airtemp Div. (for mail) Griffith Consumers Co., 1413 New York Ave., N. W., Washington, D. C., and 305 E. Columbia St., Falls Church, Va. PHIPPS, Frederick G. (Af 1930) Vice-Pres.. Pres ton Phipps, Inc., 955 St. James St., and (for mail) 5431 Eamscliffe Ave., Montreal. P. Q., Canada. PIATNITZA, John, Jr. (S 1939) (for mail) 4043 W. Parker Ave., Chicago, 111. PICKETT, Clinton A. (Af 1937; A 1923) Branch Mgr. (for mail) Herman Nelson Corp., 540 N. Michigan Ave., Chicago, and 2000 Beechwood Ave., Wilmette, 111. PICOT, John W. (A 1937) Dir., Air Cond. Div., John Taylor & Son, (Aust.) Pty., Ltd., 252 George St., Sydney, and (for mail) 19 Marine Parade, Watsons Bay, N. S. W., Australia. PIERCE, Edgar D. (A 1939; 7 1933) Mgr., Carrier Air Cond. Dept, (for mail) Electrical Products Consolidated, 585 S. Broadway, and 1365 Corona, Denver, Colo. PIETSCH, James A. (Af 1936) Consulting Engr. & Pres, (for mail) James A. Pietsch, Inc., 155 Prospect Ave., and 101 Cebra Ave., New . Brighton, S. I., N. Y. PIHLMAN, Arthur A. (Af 1928) Sales Tech. Repr. (for mail) Consolidated Edison Co. of New York, Inc., 4 Irving Place, New York, N. Y., and 98 Sherman Place, Jersey City, N. J. PIKE, Wallace H. (Af 1935) Design Engr.. New comb David Co., 5779-81 Russell St., and (for mail) 4708 Buckingham Rd., Detroit, Mich. PILLEN, Harry A. (A 1933) Owner, Mfrs. Agent, Htg., Cooling & Power Equipment (for mail) Harry A. PiJJen Co., 626 Broadway, and 2124 Crane Ave., Cincinnati, O. PINES, Sidney (Af 1920) Gen. Mgr. (for mail) Pines-Natkin Co., 209 Browder St., and 4441 Livingston Ave., Dallas, Tex. PINTO, Chester B. {A 1937) Div. Head., PIbg. and Htg. (for mail) Montgomery Ward & Co., 150-18 Jamaica Ave., Jamaica, and 11 Buena Vista Ave.. Lawrence, L. I., N. Y. PISTLER, Willard C. (Af 1934) ConsulUng Engr., 61 Leverone Bldg., 4 W. Seventh St., and (for mail) Orchard Lane & Crestview Ave., Pleasant Ridge, Cincinnati, O. PITCHER, Lester J. (Af 1929; A 1928; 7 1924) Electrimatic Corp., 2100 Indiana Ave., and (for mail) 1224 E. 69th St., Chicago, 111. PLAAG, Albert F. (A 1938) Owner (for mad) Frezon Refrigeration Service, 245 N. Warren St,, and 550 Miller Ave., Trenton, N. J. PLACE, Clyde R. (Af 1924) Consulting Engr. (for mail) 420 Lexington Ave., and 333 East 57th St., New York, N. Y. PLANT, Edward B. (Af 1938) Asst. Engr. (for mail) Canadian Pacific Railway Co.. Room 401, Windsor St. Station, and 2 Thurlow Rd., Hamp stead. Montreal. P. Q.. Canada. PLAYFAIR, George A. (A 1924) Mgr. (for mail) Johnson Temperature RegulaUng Co., 113 Simcoe St., Toronto, Ont., Canada. PLEUTHNER. Richard L. (7 1938) Engr., Buffalo Forge Co., and (for mail) 393 Starin Ave., Buffalo, N. Y. PLEWES, Stanley E. (Af 1917) Branch Mgr. (for mail) Johnson Service Co., 2853 N. 12th St., and 341 E. Hortter St., Philadelphia, Pa. PLUM, L. H. (Af 1935; A 1934) Engr. (for mail) Warren Webster & Co., 17th & Federal Sts., Camden, and 207 Guilford Ave., Collingswood, N. J. PODOLSKE, Arthur R. (A 1938) Prop., Arthur R. Podolske Sheet Metal Works, 818A E. Center St., and (for mail) 820 E. Center St., Milwaukee, Wis. POEHNER, R. E. (Af 1928) Prop, (for mail) Heating Contractor, 846 Massachusetts Ave., and 2308 Coyner Ave.. Indianapolis, Ind. POGALIES, Louis H. (Af 1931) Mech. Engr., Wilbur Watson & Associates, 4614 Prospect Ave., and (for mail) 4102 Archwood Ave., Cleveland, O. POHLE, K. F. (A 1930) Vice-Pres. (for mail) W. F. Hirschman Co., Inc., 143 Federal St., Boston, and 172 Hamilton Ave., Quincy, Mass. POLING, Dudley B. (Af 1936) Pres, (for mail) Poling Engineers, Inc., 264 Cozzens St., and 797 E. Fulton St., Columbus. O. POLLAK, Rudolf (Af 1937) Chief Engr. (for mail) Rockefeller Center, Inc., 50 Rockefeller Plaza, New York, and 79 Pinebrook Drive, Larchmont, N. Y. POLLARD, Alfred L. (A 1932) Gen. Supt. Light & Power (for mail) Puget Sound Power & Light Co., 860 Stuart Bldg., and 3009-28th Ave., W., SeatUe, Wash. POLLOCK, Carl A. (A 1937) Vice-Pres. and Gen. Mgr. (for mail) Dominion Electrohome Indus tries, Ltd., 39 Edward St., and 120 Sterling Ave., Kitchener, Ont., Canada. POND, William H. (Af 1938) Sales Engr.. Fitz- gibbons Boiler Co., 101 Park Ave., New York, N. Y., and (for mail) 820 West Front St., Plain field. N. J. . PONDER, E. A. (A 1939) Mgr. Oil Burner Dept., A. G. Rushlight & Co., 407 S. E. Morrison St., and (for mail) 1411 S. E. 25th, Portland, Ore. POPE, S. Austin (Af 1917) Pres, (for mail) William A. Pope Co., 26 N. Jefferson St.. Chicago, and 831 Ashland Ave., River Forest, 111. PORTER, Carl W. (A 1940; 7 1936) Engr. (for maill Richards & Porter, 42 W. Concord Ave., and 915 Bradshaw Terrace, Orlando, Fla. . PORTER, Noel E. (7 1938) Engr., General Air CondiUoning Co., 1313 J St., and (for mail) 2600 M St.. Sacramento Calif. ' 54 ROLL OF MEMBERSHIP POSEY, James. (Af 1919) Consulting Engr. (for mail) 1755 Baltimore Trust Bldg., and 4005 Liberty Heights Ave., Baltimore, Md. POTTER, J. Robert (A 1939; 7 1938) Design Engr., Lockwood-Green, Engrs., 2 Rockefeller Plaza, New York, and (for mail) 2 Grace Court, Brooklyn, N. Y. POUGHER, Ernest W. (Af 1939) Dir., Messrs. Ernest W. Pougher & Son, Old Trafford, and (for mail) 99, Mauideth Rd., W., Manchester, Eng land. POUNDS, Carlos A., Jr. (7 1937) Asst. Chief Htg. Engr. (for mail) Sunbeam Heating & Air Conditioning Co., 346 Peachtree St., N. E., and 116 North Ave., N. E., Atlanta, Ga. POWELL, George W., Jr. (Af 1938) Consulting Engr. (for mail) 415 Otis Bldg., 16th & Sansom Sts., Philadelphia, and 458 S. 4th St., Colwyn, Del. Co., Pa. POWERS, Earle C. (Af 1939) Sr. Partner (for mail) E. C. Powers & Son. 240 Cherry St., Philadelphia, Pa., and 22 E. Stiles Ave., Collingswood, N. J. POWERS, Edgar C. (A 1934; 7 1931) Partner (for mail) E. C. Powers & Son, 240-242 Cherry St., Philadelphia, Pa., and 309 Westmont Ave., Westmont, N. J. POWERS, F. W. {Life Member; Af 1911) Pres, (for mail) The Powers Regulator Co., 2720 Greenview Ave., and 900 Castlewood Terrace, Chicago, 111. POWERS, Lowell G. (A 1937; 7 1930) Dist. Mgr. (for mail) Carrier Corp., 795 Union Commerce Bldg., Cleveland,'and 2730 Cranlyn Rd., Shaker Heights, O. ' PRATT*, Foster J. (Af 1937) Marine Engr., U. S. Navy Yard. Puget Sound, Bremerton, and (for mail) Annapolis Terrace, Port Orchard, Wash. PRATT, Joseph C. (A 1936) Sales (for mail) Fess Oil Burners of Canada, Ltd., 1405 Drum mond St., and 12 Killamey Gardens, Pr. Claire, Montreal, P. Q., Canada. PRAWL, Frank E. (A 1940j 7 1936) Owner & Engr. (for mail) Prawl Engineering Co., Weller Bldg., and 401 E. 24th, Scottsbluff, Nebr. PREBENSEN, Harold J. (Af 1938) Vice-Pres., Air Comfort Corp., 1307 S. Michigan Ave., Chicago, and (for mail) 1066 Pine St., Winnetka, III. PREECE, Leo W. (A 1936) Htg. & Air Cond. Engr., Erie Oil Co., 1516 Myrtle St., and (for mail) R. F. D. No. 5, Erie, Pa. ' PRENTICE, O. J. (A 1927) Dir. Publicity & Public Relations (for mail) C. A. Dunham Co., 450 East Ohio St., and 850 Lake Shore Drive, Chicago,' III. PREWITT, H. B. (A 1939) Sales Engr., American Blower Corp., and (for mail) 615 E. Allen Lane, ML Airy, Philadelphia, Pa. PRICE, Charles E. (A 1933) Treas. (for mail) Keeney Publishing Co., 6 N. Michigan Ave., Chicago, and 1151 Chatfieid Rd., Winnetka, IU. PRICE, Charles F, (7 1937) Htg. and Air Cond. Engr., The Knapp Supply Co., Ohio Ave., and Dudley St., and (for mail) 1015 W. Washington St., Muncie, Ind. PRICE, D. O. (Af 1934) Htg. & Air Cond. Engr.. General Steel Wares, Ltd., 199 River St., and (for mail) 131 St. Germain Ave., Toronto, Ont., Canada. PRICE, Ernest H. (Af 1939; A 1937; 7 1934; 5 1932) Htg. Engr., W. G. Chester & Son, 179 Bannatyne Ave., and (for mail) 170 Harblson Ave., Winnipeg, Man., Canada. PRIESTER, Gayle B. (7 1935: 5 1934) Air Cond. Engr.' (for mail) Carrier Corp., Merchandise Mart, and 5904 N. Kenmore, Chicago, IU. PRINCE, Raymond F. (7 1936) Htg. & Sales Engr.. R. B. Dunning & Co., 54 Broad St., and (for mail) 27 McKinley St., Bangor, Me. PRITCHARD, William J. (A 1939; 7 1937) Carrier Corp., 212 Maple St., W. Roxbury, Mass. PROEBSTLE, Leonard (7 1938) Air Cond. Engr., Belden-Porter Co., 65 N. 17tb St., and (for mail) 4609-28th Ave., S., Minneapolis, Minn. PROIE, John (Af 1936) Gen. Mgr. (for mail) Proie Brothers, 856 W. North Ave., and 101 Dilworth St., Pittsburgh, Pa. PRYIBIL, Paul L. (A 1932) Partner. Hucker- Pryibil Co., 1700 Walnut St., and (for mail) 328 E. Phil-Ellena St., Philadelphia, Pa. PRYKE, John K. M. (A 1937) Director, Lips- combe Air Conditioning Co., Dacre House, Dacre St., London, S. W. 1, and (for mail) 216 Clive Court, Maida Vale, London, W. 9, England. PUGH, Daniel C. (S 1939) Student, Carnegie Institute of Technology, 4608 Forbes St., Pitts burgh, and (for mail) 267 Virginia Ave., Roches ter, Pa. PULLEN, Royal R. (Af 1935) Chief Mech. Engr., Homestake Mining Co., and (for mail) 109 East Hill St., Lead. S. D. PURCELL, Frederick C. (Af 1926) Sales Engr., Minneapolis-Honeywell Regulator Co., 415 Brainard St., and (for mail) 18680 Santa Rosa Dr., Detroit, Mich. PURINTON, Dexter J. (A 1923) Vice-Pres., Mahoney-Troast Construction Co.. 657 Main Ave., Passaic, N. J., and (for maU) 148 E. 53rd St., New York. N. Y. PURSELL.H. E. (Af 1919) Special Repr., Kewanee Boiler Corp., Kewanee, III. o QUALL, Clarence O. (A 1937) Owner, Quail Plumbing & Heating Co., 65 Ninth St., and (for mail) 54 Pearl St., Clintonville, Wis. QUEER, Elmer R. (Af 1933) Asst. Prof. Engrg. Research (for mail) Pennsylvania State College, Engrg. Experiment Station, and 338 Arbor Way, State College, Pa. QUICK, Blair A. (A 1938) Sales Mgr., The Inde pendent Register Co., 3747 E. 93rd SL, and (for mail) Fenway Hall, Cleveland, O. QUIRK, C. H. (Af 1916; 7 1915) Eastern Repr. (for mail) The Trane Co., 250 East 43rd St., New York, and 465 Front St., Hempstead. L. I., N. Y. R RABE, Albert E. (Af 1938) Chief Engr. (for mail) Carrier Engineering, South Africa, Ltd., Beresford House. Main & Simmonds Sts., and 152 Mowbray Rd., Greenaide ExL, Johannesburg, South Africa. RABER, Benedict F. (Af 1937) Prof, of Mech. Engrg. (for mail) University of California, Room 114 Engrg. Bldg., and 1124 Arch St., Berkeley, Calif. RACHAL, John M. (A 1936; 7 1930) Mgr., Air Cond. Dept, (for mail) Volkart Bros., 8 Clive St., and 1 Bishop Lefroy Rd., Calcutta, India. RAGATZ, Theodore E. (A 1937) Sales, Sidles Co., Airtemp Div., 14th St., and (for mail) 2222-14th St., Columbus, Nebr. . RAINE, John J. (Af 1912) Vice-Pres. (for mail) G. S. Blodgett Co., 190 Bank St., Burlington, and Essex Junction, VL RAINGER, Wallace F. (A 1930; 7 1924) Jaros, Baum & Bolles, 415 Lexington Ave., and (for mail) 441 Hawthorne Ave., Yonkers, N. Y. RAISLER. Robert K. (A 1933; 7 1930) Treas. (for mail) Raisler Corp., 129 Amsterdam Ave., and 38 East 85th St., New York, N.`Y. RALPH, David S. (7 1938) Engr. (for mail) The Walker Co., 231 Court SL, Hamilton, and 620 Kenilworth Ave., Dayton, O. RAMSAY, James W. (A 1936) Sales Engr. (for mail) King & Shepherd, 50 Church St., New York, and 8415 Fourth Ave., Brooklyn, N. Y. RAND, Fred R. (Af 1938) Htg. Engr. & Sales Mgr., Enamel & Heating Products, Ltd., and (for mail) P. O. Box 521, Sackville. N. B., Canada. RANDALL, Robert D. (A 1930) Partner (for mail) D. T. Randall & Co., 7310 Woodward Ave., and 340 E. Grand Blvd., Detroit. Mich. RANDALL, W. Clifton* (Af 1928) Chief Engr. (for mail) Detroit Steel Products Co., 2250 E. Grand Blvd., Detroit, and 770 Shirley Drive, Birmingham, Mich. RANDOLPH. C. H. (Af 1930; A 1928; 7 1926) Air Cond. Engr., Wisconsin Electric Power Co., 231 W. Michigan St., and (for mail) 1614 E. Royall Place, Milwaukee, Wis. 55 HEATING VENTILATING AIR CONDITIONING CUIDE 1940 RANZ1NGER, Gustav (5 1939) 147-05 Willett Pt. Blvd., Queens, L. N. Y. RASMUSSEN, Robert P. (Af 1931) Pres., Economy Equipment Co., 223 N. Wolcott Ave., and (for mail) 1243 E. 46tb St., Chicago. 111. RATHER, Max F. (Af 1919) Mgr.. Eastern Terri tory (for mail) Johnson Service Co.. 28 East 29th St., New York. N. Y., and 90 Orchard Drive, Greenwich, Conn. RAVEN, Andrew H. (Af 1938) Htg. Engr.. Wigman Co., 316 Perry St., and (for mail) 2119 George St., Sioux City, la. RAY, George E. {J 1939) Engr., William A. Scherff, 1827 Vauxhall Rd.. Union, and (for mail) 32 Forest Ave., Cranford, N. J. RAY, Lewis B. (Af 1932) Pres, (for mail) Ray Engineering Co., Inc., 830 Broad St., Newark, and 151 Augusta St., Irvington, N. J. RAYMER, W. F., Jr. (A 1936: 7 1934) Sales Engr. (for mail) American Blower Corp., 249 High St., Newark, and 18 Bradley Terrace, West Orange, N. J. RAYMOND. Fred-1.* {A 1929) Owner (for mail) F. I. Raymond Co., 629 W. Washington Blvd., Chicago, and Glencoe, III. RAYN1S, Theodore {A 1939; J 1934) Asst. Naval Archt., New York Navy Yard, Design Section Building No. 5. Brooklyn, and (for mail) 58 Hilltop Drive, Manhasset, L. I.. N. Y. READER, Joseph T. (A 1938) Partner (for mail) Kerr Machinery Co.. Detroit, and 263 Roosevelt PI., Grosse Pointe, Mich. REAMER, William S., Jr. (Af 1937) Vice-Pres., Treas. (for mail) Reamer Industries, Inc.. Sea board Park, and 2400 Blossom St., Columbia. S C. RECK, William E. (Af 1927) Civil Engr. (for mail) Reck Heating Co., Ltd., Esromgade 15, Copen hagen, and Sundvej 16, Hellerup, Denmark. REDRUP, Will D. (Af 1936) Pres, (for mail) Majestic Co., and 310 Randolph St., Huntington. Ind. REDSTONE, Arthur L. (Af 1931) Research Engr.. Proctor & Schwartz. 7th & Tabor Rd., and (for mail) 1636 E. Duval, Philadelphia, Pa. REED, Frederick J. (Af 1939) Asst. Prof. Mech. Engrg, Duke University, and (for mail) 263 Col lege Station. Durham. N. C. REED, Irving G. (A 1937; / 1934) Asst. Supt. and Chief Engr. (for mail) Grant Building. Inc., 420 Grant Bldg., and 3227 Middletown Rd., Sheradan. Pittsburgh, Pa. . REED, Van A., Jr. (Af 1930) Mech. Engr. (for mail) Federal Engineering Co., 239-4th Ave., Pittsburgh, and 114 Water St., Elizabeth, Pa. REED, Virgil C. (Af 1938) Owner (for mail) James H. Pinkerton Co., 927 Howard St., and 1234 Second Ave., San Francisco, Calif. REED, William H., HI (A 1938) Sales Engr. (for mail) Dravo Corp., Industrial Dept., 302 Penn Ave., and 5675 Beacon St.. Pittsburgh, Pa. REGER, Henry P. (Af 1934) Pres.-Treas. (for mail) H. P. Reger & Co., 1501 East 72nd Place, and 6939 Bennett Ave., Chicago, lit. REID, Henry P. (Af 1931; A 1927) Operating Engr. (for mail) Universal Atlas Cement Co., 135 E. 42nd St., Chrysler Bldg., New York, and 72 Mercer Ave., Hartsdale, N. Y. REID, Herbert F. {A 1932) Partner, Reid-Graff Plbg. Co.. 1417 Peck St.. Muskegon Heights, Mich. REIF, Allan F. (Af 1937) Pres, (for mail) Reif- Rexoil, Inc., 37-43 Carroll St., Buffalo, and 10 Livingston Pkwy., Snyder. N. Y. REIF, Charles A. (Af 1937) Vice-Pres., Treas. (for mail) Reif-Rexoil, Inc., 37-41 Carroll St., Buffalo, and 77 Ruskin Rd., Eggertsville, N. Y. REIFSCHNEIDER, Jake {A 1938) Supt. of Maintenance (for mail) Eppley Hotels Co., 1802 Dodge St., and 2121 Emmet. St., Omaha, Nebr. REILLY, Bertram B. (J 1938) Engr. (for mail). Dravo Corp., Air Cond. Dept., 300 Penn Ave., Pittsburgh, and Ridgeview Apt., Ridgewood Ave., West View, Pa. REILLY, Charles E. (A 1936; J 1928) Pres., Wynnefield & Bala Steam Heat Cos. (for mail) 4920 City Line Ave., Philadelphia, Pa. REILLY, J. Harry (Af 1931; J 1929) Sales Engr.. American Radiator & Standard Sanitary Corp.. 528 Ferry St., Newark, and (for mail) 14 Watson Ave., East Orange, N. J. REINKE, Alfred G. (A 1940; J 1933) Secy., Gus Reinke Machinery & Tool Co., 63 Dickerson St.. Newark, and (for mail) 321 Park Place. Irving ton, N. J. REINKE, Louis F. (A 1937) Owner (for mail) Reinke Sheet Metal Works, 534 S. Fifth St., and 1535 W. Walker St., Milwaukee, WisREINOLDI, Charles (/ 1937) Gas Engr. (for mail) Consolidated Gas, Electric Light & Power Co., 1068 Front St., and 3965 Wilsby Ave., Baltimore. Md. REIS, Robert (J 1939) Engr. & Estimator, Reis & O'Donovan, Inc., 12 W. 21st St., and (for mail) 440 Park Ave., New York, N. Y. REISBERG. Lester K. (A 1939) Vice-Pres. (for mail) Goodin Co., 707 N. Third St., and 4434 Central Ave.. Minneapolis, Minn. RENOUF, E. Prince (Af 1933) Air Cond. Supvr.. Westinghouse Elec. & Mfg. Co.. 1005 Insurance Bldg., and (for mail) 3431 Rankin St., Dallas, Tex. RESS. Otto J. (A 1940; / 1937) Gas Htg. Engr., iowa-Nebraska Light & Power Co., 1401 O St., and (for mail) 1900 South I7th, Lincoln, Nebr. RETTEW, Harvey F. (Af 1929) Chief Engr., Board of Education, 21st St. and the Parkway, and (for mail) 4039 Chestnut St., Philadelphia, Pa. REYNOLDS, Thurlow W. (Af 1922) Consulting Engr. (for mail) 100 Pinecrest Drive, Hastings- on-Hudson, N. Y. REYNOLDS, W. V, (A 1928) Pres., Walter Reynolds. Inc., 861 Third Ave., New York, N. Y. RHINE, George R. (A 1938) Air Cond. Engr. (for mail) San Antonio Public Service Co., 201 N. St. Mary's St., and 322 E. Laurel St., San Antonio, Tex. RHOTON, W. R. (Af 1936) Pres., The W. R. Rhoton Co.. 1305 East 107th, Cleveland, and (for mail) 1728 Lee Rd., Cleveland Heights, O. RICE, Clarence J. (A 1923) Pres, (for mail) Sterling Engineering Co., 3738 N. Holton St., and Rte. 6, Box 374, Milwaukee, Wis. ' RICE, Robert B. (Af 1934) Prof, of Experimental Engrg. (for mail) State College of Agr. & Engrg., University of North Carolina, and 2902 White Oak Rd., Raleigh,.N. C. RICHARD, Edwin J. (Af 1933) Owner (for mail) Edwin J. Richard Equipment Co., 2137 Reading - Rd., and 3147 Victoria Ave., Cincinnati. ORICHARDS, Guy H. (A 1939) Mgr. Htg. Dept.. Crane Co., and (for mail) 420 N. 78th St.. Birmingham. Ala. RICHARDSON, Henry C. (Af 1934) Partner. Williams & Richardson, 204 Dooly Bldg., and (for mail) 1433 Harvard Ave.. Salt Lake City, Utah. RICHARDSON, Laurence S. (A 1939) Mgr. & Engr. of Heat Dept., Stark-Davis Co.. 110 S. W. Front St., and (for mail) 6929 S. E. Yamhill St., Portland, Ore. RICHARDSON, Robert D. (J 1938) Htg. Engr.. Hope's Heating & Lighting, Ltd.. Smethwick, and (for mail) 85 Silhill Hall Rd., Solihull, Birmingham, England. RICHFIELD. Nicholas H. (Af 1937) Engr., Oil Burner Div., American Radiator & Standard Sanitary Corp., 40 West 40th St., New York, and (for mail) 173 N. Tyson Ave., Floral Park, L. I., N. Y. RICHTMANN, W. M.* (A 1932; J 1926) Assoc. Prof, of Mech. Engrg. (for mail) Texas College of Arts and Industries, and 600 W. Richards St., Kingsvilte, Tex. RIDLEY, Walter H. (Af 1939) Mgr.. Dryer Div., Riggs & Lombard, Inc., Suffolk St., Lowell, and (for mail) High St., Chelmsford, Mass. RIES, Lester S. (Af 1929) Supt. of Bldgs, and Grounds (for mail) Oberlin College, 32 E. College St., and 221 Woodland Ave., Oberiin. O. ROLL OF MEMBERSHIP . RIESMEYER, Edward H., Jr. (A 1936; J 1930) Engr., Schaffer Heating Co., 231 Water St., and (for mail) 4702 Stanton Ave., Pittsburgh, Pa. RIETZ, Elmer W.* (Af 1923) Mgr., Specialty Div. (for mall) The Powers Regulator Co., 2720 Greenview Ave., Chicago, and 2250 S. Sheridan Rd., Highland Park, 111. ' RIGBY, Robert A. (A. 1937) Salefi Engr., Air Conditioning (for mail) 3325 North 48th Ave., and 109 Drake Court Annex, Omaha, Nebr. R1ST, Lawrence M. (A 1939; J 1937) Sales Engr. (for mail) 1753 Insurance Exchange Bldg., 175 W. Jackson Blvd., Chicago, lit., and 3326 Harney, Omaha, Nebr. RITCHIE, A. G. (Af 1933) Pres, (for mail) John Ritchie, Ltd., 102 Adelaide St., E., and 41 Gar field Ave., Toronto, Ont., Canada. RITCHIE, E. J. (Af 1923) Vice-Pres.. Sales; Sarco Co., Inc., 183 Madison Ave., New York, and (for mail) 2 Grace Court, Brooklyn, N. Y. RITCHIE, William {Life Member; Af 1909) 17 Van Reipen Ave., Jersey City, N. J. RITTER, Arthur (Af t9ll) Dist. Mgr. (for mail) American Blower Corp., 50 West 40th St., New York, and 29 Edgemont Rd., Scarsdale. N. Y. RIVARD, Melvin M. (M 1935) Mgr., Rivard Sales Co., 4550 Main SL, and (for mail) 1805 West 49th St. Terrace, Kansas City, Mo. ROBB, Joseph E. (A 1936) Sales Engr., Minne- apolis-Honeywell Regulator Co., 2753-4th Ave., S., Minneapolis, Minn., and (for mail) 1737 Mississippi, Lawrence. Kan. ROBERTS, Henry L. (Af 1916) Htg. Engr. and . Contractor (for mail) 228 North 16th St.. Philadelphia, and 1014 Allston Rd.. Brookline, Del. Co. (Upper Darby P. O.) Pa. ROBERTS, Henry P. (A 1936) Secy, (for mail) Roberts-Hamilton Co., 713 South 3rd St., and 1901 James Ave., S., Minneapolis. Minn. RODGERS. Joseph S. (A 1937: J 1934) Principal Engrg. Draftsman, U. S. Government, War Dept., Edgewood Arsenal, Edgewood, and (for mail) 1 Third Ave., Brooklyn Park, Md. RODMAN, R. W. (Af 1922) Supt. of Plant Opera tion (for mail) Board of Education, City of New York, 500 Park Ave., and 175 West 73rd St.,' New York, N. Y. ROEBUCK, William, Jr. (Af 1917) Mfrs. Agent (for mail) 220 Delaware Ave., and 1240 Delaware Ave., Buffalo. N. Y. ROGERS, Robert C. (A 1937) House Htg. Engr.. Community Natural Gas Co., and (for mail) 4020 Dickason St., Dallas, Tex. ROGERS, Thomas L. C. (A 1939) Managing Dir. & Chief Engr. (for mail) The National Air Conditioning Co.. Ltd., 200 Piccadilly SL, W., and 158 Victoria St., London, Ont., Canada. ROLLAND, Sverre L. (A 1934) Design Engr. (for mail) Oklahoma Gas & Electric Co.. 321 N. Harvey Ave., and 2131 Northwest 20ti) St., Oklahoma City. Okla. ROLLOSSON, John A. (A 1940; J 1938) Pres, (for mail) Rollosson-Keeland Co., 3714 Main SL, and 1918 McGregor Ave., Houston, Tex. RONS1CK, Edward H. (Af 1937) House Htg. Engr. (for mail) The SL Louis County Gas Co., 231 W. Lockwood, Webster Groves, and 7739 Stanford Ave., University City, Mo. ROOT, Edwin B. (Af 1936) Mgr. Htg. & Air Cond. Dept., Nelson Co., 2604 Fourth Ave., Detroit, and (for mail) 964 Pierce SL, Birmingham, Mich. ROSE, Harold J. (Af 1937) Sr. Industrial Fellow (lor mail) Mellon Institute, 4400 Fifth Ave., and 219 Lytton Ave., Pittsburgh. Pa. ROSE, Howard J.* (Af 1934) Mgr. of Engrg. Sales, Suburban Air Conditioning Corp., 7 Depot Plaza, White Plains, and (for mail) 100 Siebrecht Place. New Rochelle, N. Y. ROBERTSON, James A, M. (A 1936) Vice-Pres. ROSE, Jerome C. (Af 1937) Air Cond. Engr., (for mail) The James Robertson Co., Ltd., 946 William St., Montreal, and 109 Sunnyside Ave., Westmount, P. Q,, Canada. Buensod-Stacey Air Conditioning, Inc., 60 East 42nd St.. New York, and (for mail) 8831 Fort Hamilton Pkwy.. Brooklyn, N. Y. ROBINSON, Arthur S. (Af 1936) Engrg. Dept., ROSE, William H.t Jr. {J 1938) Sales Engr. (for E. I. duPont de Nemours Co., c/o Dye Works. mail) B. F. Sturtevant Co., 812 Michigan Theatre Carney's Point. N. J., and (for mail) 730 Ogden Bldg., and 5442 2nd Blvd., Detroit, Mich. Ave., Swarthmore, Pa. ' ROSEBROUGH, J. Stoddard (A 1937) Sales ROBINSON, Donald M. (A 1936) Sales Engr. Engr. (for mail) L. J. Mueller Furnace Co., 4246 (for mail) Buffalo Forge Co., 640 Woodward Bldg.. Washington. D. C., and 12 Cedar St., Forest Park Blvd., and 5917 Washington Ave., St. Louis, Mo. Hyattsville, Md. ROSEBROUGH, Robert M. (Af 1920) Branch ROBINSON, Edgar R. (A 1938) Draftsman, Hull . Ventilation, Shipyard Div., Bethlehem Steel Co.,v Sparrows Point, and (for mail) 5434 Jonquil Ave., Baltimore, Md. . ' ROBINSON, George L. (A '1935) Draftsman and Designer, E. I. duront de Nemours (for mail) 210 West 28th St., Apt. 1, Wilmington, Del. ROBINSON, Jack A. (A 1940; J 1936) Air Cond. . Engr., Australian Gas Light Co., Parker St., Sydney (for mail) Box 481 AA, G. P. O., Sydney, . and 595 New South Head Rd., Rose Bay, N.S.W. Australia. Mgr. (for mail) L. J. Mueller Furnace Co., 4246 Forest Park Blvd., SL Louis, and 519 S. Gore Ave., Webster Groves, Mo. ROSEBY, Thomas A. (Af 1939) Chief Design Engr. (for mail) Carrier Australasia, Ltd., 36-40 Bourke St., Sydney, N. S. W,, and 11 Gillies St., North Sydney, N. S. W., Australia. ROSELL, Axel F. (Af 1935) Engr., A. B. Svenska Flaktfabriken, Kungsgatan 16-18, Stockholm, and (for mail) Per Hdrbergs v&g 4, S. Angby. Sweden. ROSEN, Edmond J. (A 1939) Mgr. Temperature Control Dept., Parker-Carpenter, Inc. (for mail) ROCHE, I. F. (A 1936) Mgr., Fess Oil Burners of 991 Bryant St., San Francisco, and 3272 Dakota Canada, Ltd., 1405 Drummond St., and (for mail) St., Oakland, Calif. 4709 Cote St. Catherine Rd., Montreal, P. Q., Canada. ROSENBERG, Irwin (5 1939) Student Carnegie Institute of Technology, and (for mail) 1003 ROCK, George A. (Af 1937) Plbg. & Htg. Con Mirror St., Pittsburgh, Pa. ' tractor (for mail) 1351 S. W. 8th St., Miami, Fla. ROSENBERG, Philip (A . 1928) Secy.-Treas., ROCKWELL, Theodore F. (Af 1933; J 1932) Universal Fixture Corp.. 135 West 23rd St., and Instructor (for mail) Carnegie Institute of Tech (for mail) 250 West 104th St.. New York, N. Y. nology, Schenley Park, and Glenover Place, ROSENBLATT, Arthur M. (Af 1938) Partner Aspinwall, Pittsburgh, Pa. (for mail) Rosenblatt & Hunt, P. O. Box 828, RODEE. E. John (Af 1936) Chief Engr. (for mail) John B. Pierce Foundation, 290 Congress Ave., New Haven, and 130 Bellevue Ave., West Haven, Conn. 923 Virginia St., E., and 1250 Edgewood Drive, Charleston, W. Va. ROSS, John D. {A 1937) Sales Engr. (for mail) Railway & Engineering Specialities, Ltd., 637 . RODENHEISER, George B. (Af 1933) Asst. Dir. (for mail) David Rankenjr. School of Mechanical Trades, 4431 Finney Ave., and 3639a Dover Place, St. Louis, Mo. RODGERS, F. A. (A 1934) Pres, (for mail) Rodgers Engineering Co., Thomas Bldg., and 3421 St. Johns Drive, Dallas, Tex. Craig St., West, and 4376 EarnkJiff Ave., Montreal, P. Q., Canada. ROSS, J. O.* (Af 1920) Pres., Ross Industries Corp., 350 Madison Ave., New York, N. Y. ROSS, Roderick (Af 1937) Consulting Engr. (for mail) Nicholas Bldg., 37 Swanson St., P. O. Box 1381 M, Melbourne, C. 1, and 5 Bums St., Elwood. Melbourne, S. 3, Australia. 57 V HEATING VENTILATING AIR CONDITIONING GUIDE 1940 ROSSITER, Irvin J. (A 1939) Sales Engr. (for mail) American Blower Corp., 1011 Majestic Bldg., and 1317 N. Franklin PI., Milwaukee, Wis. ROTH, Charles F. (A 1930) Pres, (for mail) International Exposition Co., Grand Central Palace, and 141 East 36th St., New York, N. Y. ROTH, Harold R. (M 1935) Sales Engr. (for mail) Canadian Sirocco Co., Ltd., 57 Bloor St., W., and 5 Castleview. Toronto, Ont., Canada. ROTHMANN, S. C. (M 1936) Industrial Hygiene Engr. (for mail) West Virginia Compensation Commission, State Capitol Bldg., and 2008H Kanawha St., Charleston, W. Va. ROTTMAYER, Samuel I. (A 1933; 7 1928) Mech. Engr. (for mail) Samuel R. Lewis, Cons. Engr., 407 S. Dearborn St., and 8641 Drexel Ave., Chicago, 111. ROWE, Irving E. (A 1936) Engr., Erie Sheet Metal Works, 1704 Houston Ave., and (for mail) 2517 Fletcher St., Houston, Tex. ROWE, William A.* (M 1921) (Council, 1929 1931) Mech. Engr. (for mail) The Trane Co., LaCrosse. Wis.. and 718 Longfellow Ave., . Detroit. Mich. ROWE, William M. (.7 1936) Salesman (for mail) American Blower Corp., 1302 Swetland Bldg., Cleveland, and 151 Bradley Ave., Chagrin Falls, ROWLEY, Frank B.* (M 1918) (Presidential Member) (Pres., 1932; 1st Vice-Pres.. 1931; 2nd Vice-Pres., 1930; Council, 1927-1933) Prof, of Mech. Engrg. and Director of Experimental Engrg. Lab., University of Minnesota, and (for mail) 4801 E. Lake Harriet Blvd., Minneapolis. Minn. ROY, Arthur C. (A 1937) Metropolitan Sales Mgr., Hoffman Specialty Co., Inc., 500 Fifth Ave., New York, N. Y., and (for mail) Box 507, Morristown, N. J. ROY, Leo (A 1937) Power Sales Engr. (for mail) Quebec Power Co., 229 St. Joseph St., and 41 Laurentide Ave., Quebec, P. Q., Canada. ROYER, E. B. (M 1928) Designing Engr., Fosdick & Hilmer, Cons. Engrs., 1703 Union Trust Bldg., and (for mail) 6635 Iris Ave., Cincinnati, O. RUDD, Dann J. (M 1937) Htg. & Vtg. Engrg.. N. Y. City Board of Education, 49 Flatbush Ave. Extension, Brooklyn, and (for mail) 369 Deer Park Ave., Babylon, L. I., N. Y. RUEMMELE, Albert M. (7 1938) Sales Engr. (for mail) L. L. Silkensen & Co., Inc., 412-23rd St., and 3628-0H. Galveston, Tex. RUFF, Adolph G. (M 1935) Supt. of Power, U. S. Playing Card Co., Park Ave., Norwood, and (for mail) 3824 Woodford Rd., Cincinnati, O. RUFF, DeWltt C. (M 1922) Healy-Ruff Co.. 765 Hampden Ave., St. Paul, Minn. RUFF, Herbert A. (A 1938) Pres. & Treas., Herbert A. Ruff, Inc.,39 Olcott Place. Station E.. Buffalo, N. Y. RUGART, Karl (A 1924) Warren Webster & Co. (for mail) 26 S. 20th St.. Philadelphia, and 612 Bryn Mawr Ave., Narberth, P. O., Penn Valley, Pa. RUGGLES, Robert F. (M 1936; A 1927; 7 1926) *Dist. Mgr., Autovent Fan & Blower Co., 2 Rector St., New York, and (for mail) 15 Gregg Place. Randall Manor, S. I., N. Y. RUMMEL, Adolph J.* (M 1937) Air Cond. Engr. (for mail) San Antonio Public Service Co., 201 N. St. Marys St., and 319 Thorman Place, San .Antonio, Tex. RUNKEL, Charles (M 1935) Pres, (for mail) Acme Heating & Ventilating Co., Inc., 4224 S. Lowe Ave., Chicago, 111. RUPLE, Paul E. (A 1936) Owner, Gen. Mgr., Bradford Oil Burner Co., 61 Main St., Bradford, Pa. RUPPERT, C. Farrell (5 1939) Student, Purdue University, 400 Northwestern Ave., West Lafay ette. Ind. RUSSELL, Edward A. (M 1936) Chief Engr., Vapor Car Heating Co., Inc., 1600 S. Kilbourn Ave., and (for mail) 8103 Dorchester Ave., Chicago, 111. - - RUSSELL, J. N. (Life Member; M 1899) Managing Dir., Rosser & Russell. Ltd., (for mail) Romney House, Marsham St., Westminster, and Fernacres Fulmer. Buckinghamshire, England. RUSSELL, Wayne B. (A 1936) Engr., Russell Furnace Co., Inc., 601 N. Monroe, and (for mail) 1203 S. Cedar, Spokane, Wash. . RUSSELL, William A. (M 1921) (Council, 1934- 1939) Hoffman Specialty Co., and (for mail) 628 West 57th Terrace, Kansas City, Mo. RYAN, James D. (M 1935) Supt. and Engr., Whitney National Bank, St. Charles and Gravier - St., and (for mail) 4962 D'Montluzin St.. New Orleans. La. ' RYAN, Joseph B. (M 1938) Chief Engr. & Mgr. (for mail) Engineering Service Co., and 3904' Tracy Ave-. Kansas City, Mo. ' RYAN, William F. (A 1939; 7 1933) Sales Engr., The Salina Supply Co., 302-304 North Santa Fe and (for mail) 310 West Republic, Salina, Kan. RYBOLT, Arthur L. (A 1938) Gen. Mgr', (for mail) The Rybolt Heater Co., Miller St., and 75 Samaritan Ave., Ashland, O. . RYERSON, Herbert E. (M 1937).Archts. & Bldre. Div. (for mail) Peoples Gas Light & Coke Co., 122 S. Michigan Ave., Chicago, and 908 S. Wheaton Ave., Wheaton, 111. s SABIN, Edward R. (M 1919) Pres., E. R. Sabin & Co., 4710-12 Market St., Philadelphia, Pa. SABLE, Edward J. (M 1939) Treas. (for mail) The T. O. Murphy Co., 25-27 E. College St., and 246 W. Lorain St., Oberlin; O. SADLER, C. Boone {M 1928) Associate Civil Engr. (for mail) 11th Naval Dist., and 4828. Orchard Ave., San Diego, Calif. SAGINOR, S. V. (M 1939) Mech. Engr., Carbide & Carbon Chemicals Corp., South Charleston, and (for mail) 1420 Virginia St., Charleston, * W. Va. .. SAHLMANN, Frank L. (A 19371 Member, Trans portation Dept., Electrical Mfg. (for. mail) General Electric Co., and 3926 Beech Ave., Erie, Pa. * SAITO, Shozo (M 1923) (for mail) Saito Shozo Shoten, Ltd., Marunouchi Bldg., Opposite Tokyo Station 3, No. 4, 3 Chome, Kamata-Ku, Tokyo, Japan. ' SALE, Francis B. (A 1939) Sales Engr., Preferred Utilities Co., 33 w. 60th St., New York, N. Y., and (for mail) 2032 Belmont Rd., Washington, D. C. _ SALINGER, Robert J.` (7-1937) Mech. Engr. (for mail) Reginald F. Taylor. Consulting Engineer, 909 Bankers Mortgage Bldg., and 1654 Danville, Houston, Tex. - SALLANDER. H. A. (A 1937) Branch Mgr., Sidles Co., Airtemp Div., 502 S. 19th St., and (for mail) 4514 Fontenelle Blvd., Omaha, Nebr. SALTER, Ernest H. (M 1936) Engr. (for mail) Electrical Testing Laboratories, 2 East End Ave., New York, and 182 Cleveland Ave., Great Kills, S. I.. N. Y. SAMPSON, Edwin T. (A 1938) Mgr., Acoustical Dept, (for mail) Atlas Asbestos Co., Ltd., 110 McGill St., and 5382 Clanranald Ave., Montreal. P. Q...Canada. SAMUELS, Sidney (A 1928; 7 1925) Pres, (for mail) Sidney Samuels, Inc., 146 W. 99th. St., and 245 W. 107th St., New York, N. Y. SANBERN. E. N.* (M 1923) Engr. & Asst. Secy., Hoffman Specialty Co., Inc., 500 Fifth Ave., and (for mail) 523 West 112th St.. New York. N. Y. SANDERS. Charles M., Jr. (7 1938) Air Cond. Syndicate Repr. (for mail) Westinghouse Electric & Mfg. Co.. 20 N. Wacker Drive, and 5830 N. Kenmore. Chicago, 111. '' SANDFORT, John F. (7 1938) Instructor in Mech. Engrg. (for mail) Mech. Engrg. Dept., Iowa State College, and 8213^ Duff Ave:. Ames, la. ' - ' SANDS. CHve C. (Af 1929) G. P. O. Box 601 F. F.. Sydney, N. S. W.. Australia. ' 58 ROLL OF MEMBERSHIP SANFORD, Arthur L. (M 1915) Mech. Engr., SCHMUTZ, Jean (M 1933) Adnunistrateur- C. H. Johnston, Archts. and Engrs.. 360 Robert Delegue (for mail) Societe P. R. S. M,, 8 Passage St., and 1129 Portland Ave., St. Paul, Minn. de l'Atlas, Paris I9e, and 18, rue Dufrenoy, Paris, SANFORD, S. S.* {M 1930) Sales Engr. (for mail) 16e, France. The Detroit Edison Co.. 2000 Second Ave., and SCHNEIDER, Charles H. (7 1937) Sales Engr. 1503 Seyburn Ave., Detroit. Mich. (for mail) llg Electric Ventilating Co., 1031 SAPP, Charles L. (A 1936) Sales Mgr.. Farquhar Commercial Trust Bldg., Philadelphia. Pa., and Furnace Co., and (for mail) 620 North Walnut 222 Second Ave., Haddon Heights, N. J. St., Wilmington, O. SAUNDERS, L. P. (M 1933) Chief Engr., Research Div. (for mail) Harrison Radiator Div., General Motors Corp., and 507 Pine St., Lockport, N. Y. SAURWEIN, George K. (M 1938) Supt. Engrg. Dept, (for mail) Harvard University, Lehman Hall, Cambridge, and 247 Slade St., Belmont, Mass. - SAWDON. W. M.* (M 1920) Prof, of Experimental ' Engrg. (for mail) Cornell University, College of Engrg., and 1018 E. State St., Ithaca, N. Y. SAWHILL, R. V. (A 1929) Exec. Vice-Pres. (for mail) Domestic Engineering Co., 110 East 42nd St., New York, and 115 Townsend Ave., Pelham Manor, N. Y. SCALINGI, Giro R. (7 1940; S 1938) Sales Engr., Melchoir,' Armstrong, Dessau Co., 614 Memorial Drive, Cambridge, and (for mail) 94 Josephine Ave., Somerville, Mass. SCANLON, Edward L. (A 1934) Chief Htg. Engr., Equitable Gas Co., 435 Sixth Ave., and (for mail) 3310 Regan Ave., Brentwood, Pittsburgh, Pa. SCARLETT, William J. (M 1936) Kooler-Keg SCHNELL, Robert H. (A 1938) Asst. Mech. Engr. (for mail) B. E. Landes, 915 Hubbell Bldg., and 1617-33rd St,, Des Moines, la. SCHOEFFTER, Hans M. (7 1939) Sales Engr. (for mail) Aerofin Corp., 410 S. Geddes St., and 666 W. Onondaga St,, Syracuse, N. Y. SCHOENHOFEN, Leo H., Jr. (7 1938) North western University, Evanston, III SCHOENIJAHN, Robert P. (M 1919) Consulting Engr. (for mail) Industrial Trust Bldg., and 719 Nottingham Rd., Wilmington, Del. SCHOEPFLIN, Paul H. (M 1920) Pres, (for mail) Niagara Blower Co., 6 E. 45th St.. New York, and 91 Valley Rd., Larchmont, N. Y. SCHOLL, Howard O. (7 1938; S 1937) Engr., Colfax, 111. SCHREIBER, Herbert W. (A 1937) Sales (for mail) Johnson Service Co., 507 East Michigan St., and 3136 N. Eighth St., Milwaukee, Wis. SCHROEDER, William R. (A 1939) Sales Engr. (for mail) General Heating Corp., 7120 N. Clark St., Chicago, and 326 Custer St., Evanston, 111. Div., Novadel Agene Corp., Belleville, and (for SCHROTH, August H. (M 1911) N. Y. Prof. mail) 214 Park St., Montclair, N. J. Engr. Lie. No. 4550; N. Y. Mgr., Columbia SCHAD, Clifford A. (A 1938; 7 1937) Engr., Radiator Co., 101 Park Ave., Rm. 808, New United States Air Conditioning Corp., 2101 N. E. York, N. Y.. and (for mail) 167 N. Grove St., Kennedy St., and (for mail) 4425-43rd Ave., S., East Orange, N. J. Minneapolis, Minn. SCHUBERT, Arno G. (Af 1939) Asst. Prof. Mech. SCHAFER, Harry C. (M 1937) Sales Mgr. (for Engrg., Renssalaer Polytechnic Inst., Troy, and mail) Iroquois Gas Corp., 45 Church St., Buffalo, (for mail) 1301 Broadway, Watervliet, N. Y. and 197 Union St., Hamburg, N. Y. SCHECHTER, Jack E. (7 1937) Service Engr., S. J. O'Brien Sales Corp., 124 W. 124th St.. New York, and 816 Eastern Parkway, Brooklyn, N. Y. SCHECHTER, John P. (7 1935) Engr.. J. L. Skuttle Co., 1015 Franklin St., and (for mail) 1812 Burns Ave., Detroit, Mich. SCHEIDECKER, Daniel B. (A 1919) Secy, (for mail) Hunter-Clark Ventilating System Co., 2800 Cottage Grove Ave., and 4626 N. Kilbourn Ave., Chicago, 111. SCHERMER, Richard (7 1938; 5 1936) Sales Engr., American Radiator & Standard Sanitary Corp., 40 W. 40th St., New York and (for mail) 40-67 Hampton St., Elmhurst., L. I., N. Y. SCHERNBECK, Fred H. (A 1930) Salesman (for SCHUETZ, Clyde C. (A 1936) Research Engr. or mail) United States Gypsum Co., 1253 giversey Parkway, and 2728 W. Agatite Ave., Chicago, 111. SCHULEIN, Ernst H. (A 1939; 71937) Consulting Engr., Birch & Krogboe, 31 V. Farimagsgade, Copenhagen V., and (for mail) 3 Dalgas Blvd., Copenhagen F., Denmark. SCHULER, William B. (A 1937) Sales, Taco Heaters, Inc., 342 Madison Ave., New YoTk, .N. Y., and (for mail) 7655 Merrill Ave., Chicago, 111 SCHULTZ, Albert W. (Af 1936) Engr., Grinnell Co., Inc., 240-7th Ave., S., and (for mail) 5204 France Ave., S., Minneapolis, Minn. . mail) William Bros Boiler & Mfg., Co., Nicollet SCHULTZ, Stewart F. (A 1938) Sales Engr., Island, and 5045. Portland' Ave., Minneapolis, Minn. Bruce Wigle Co., 9117 Hamilton Ave., and (for mail) 19312'Yacama, Detroit, Mich. SCHERRER, Leon B. (7 1936) Engr., St. Louis SCHULZ, Edward L. (7 1937) Engr. (for mail) Cooperage'Co., 101 Arsenal St.-,and (for mail) Carrier Corp., 12 S. 12th St., Philadelphia, and 6112 Simpson Terrace, St`. Louis, Mo. 411 Pembroke Rd., Bala-Cynwyd, Pa. SCHLICHTER, Charles F. (M 1938) Dist. Mgr., Surface Combustion Corp., 600 W St., N. E., SCHULZ, Howard I. (A 1915) Crane Co., 1223 W. Broad St., Richmond, Va. Washington, D. C.t and (for mail) 6740 Fairfax Rd., Bethesda, Md. SCHLICHTING, Walter G. (M 1932) Mgr.. Air SCHULZE, Ben H. (M 1921) Eastern Sales Mgr. (for mail) Kewanee Boiler Corp., 37 W. 39th St., and 67 Park Ave., New York, N. Y. Cond. Dept., Clarage Fan Co., North & Porter Sts., and (for mail) 1417 W. Lovell St., Kala mazoo, Mich. SCHMID, John U. (J 1938) Sales Engr., Louis SCHURMAN, John A. (M 1936; 7 1935) Sales Engr. (for mail) York Ice Machinery Corp., 2700 Washington Ave., N. W., Cleveland, and 14507 Delaware Ave., Lakewood, O. Allis Co., 427 E. Stewert, and (for mail) Milwau kee Athletic Club, Milwaukee, Wis. SCHMIDT, E. Georg (M 1938) Consulting Engr., SCHWARTZ, Jacob (A 1936; 7 1929) Contractor (for mail) Samuel Schwartz & Son, Inc., 30 West 27th St., Bayonne, and 12 Van Houten Berlin-Wilmersdorf, Kaiserallee 43, Germany. Ave., Jersey City, N. J. SCHMIDT. Harry (M 1937) Air Cond. Engr., SCHWARTZ, Maurice (A 1938) Air Cond, Fedders Mfg. Co., Inc., 57 Tonawanda St., and (for mail) 233 Norwalk Ave., Buffalo, N. Y. Supervisor (for mail) Queens Borough Gas & Electric Co.. 1610 Far Rockaway Blvd., Far SCHMIDT, Karl, Jr. (7 1937) House Htg. Engr., Rockaway. and 1445 Broadway, Hewlett, L. I.. Michigan Consolidated Gas Co., 415 Clifford, N. Y. and (for mail) 14438 Mayfield Ave., Detroit, Mich. SCHWARTZ, Norman E. (M 1939; A 1938) Gen. Mgr., Sidles Co., Airtemp Div., 502 S. 19th, and SCHMIELER, Joseph B.* (7 1938) Research (for mail) 4611 Davenport St., Omaha, Nebr. Engr., A.S.H.V.E. Research Lab., U. S. Bureau of Mines, 4800 Forbes St., and (for mail) 220 Zara St., Pittsburgh 10, Pa. SCOFIELD, Paul C. (A 1937; 7 1933) Engr., Lockheed Aircraft Corp., Burbank, and (for mail) 3879 Edenhurst Ave., Los Angeles, Calif. 59 fTSETIOgeKS HEATING VENTILATINC AIR CONDITIONING GUIDE 1940 SCOTT, Allison F. H. (Af 1937) Vice-Pres, (for mail) Hoffman Specialty Co.. Inc., 500 Fifth Ave., and Columbia Club, 4 W. 43rd St., New York, N. Y. SCOTT, G. M. (Af 1915) Pres, (for mail) Child & Scott-Donohue, Inc., 153 East 38th St., New York, and Fort Hill Village, Scarsdale. N. Y.. SCOTT, William P., Jr. (7 1939) Mgr. Htg. Dept., Scott Co., 243 Minna St., and (for mail) 255 Santa Paula. San Francisco, Calif. SCOTT1, Frederico D. (Af 1939) Tech. Dir., G. De Micheli & C. S. A., and (for mail) Via Brunelleschi, 4, Florence, Italy. SCRIBNER, Eugene D. (A 1933; 7 1929) Sales Engr., R. C. Jones, Jr., 331 E. 28th St., New York, N. Y., and (for mail) Diamond Hill Rd., Scotch Plains, N. J. SEAL, Alfred T. (Af 1938) Air Cond. Engr. & Asst. Purchasing Agent, Research Corp., Bound Brook, and (for mail) 60 Jennings Lane, North Plainfield. N. J. SEARLE, William J., Jr. (Af 1937) Air Cond. Engr., The Ballinger Co.. 105 S. 12th St., Phila delphia, and (for mail) 207 Maple Ave., Narberth, Pa. SEARS, Charles B. (7 1938) College Repr., John Wiley & Sons, Inc., 440-4th Ave., New York, N. Y. SEEBER, R. R.+ (Af 1934) Prof. Mech. Engrg. Dept., Michigan College of Mining 8c Technology, Houghton, Mich. SEELBACH, Herman, Jr. (A 1937) Sales Engr., Minneapolis-Honeywell Regulator Co., 45 Allen St., and (for mail) 280 Crescent Ave., Buffalo, N.Y. SEELERT. Edward H. (A 1935) Secy.-Treas. (for mail) McQuay, Inc., 1600 N. E. Broadway, and 2927 Ulysses St., N. E., Minneapolis, Minn. SEELEY, L. E.* (Af 1930) Asst. Prof, of Mech. Engrg. (for mail) Mason Laboratory, Yale Uni versity, and 130 Event St., New Haven, Conn. SEEL1G, A. E. (Af 1926) Pres. & Gen. Mgr., L. J. Wing Mfg. Co., 154 W. 14th St., and (for mail) 640 Riverside Drive, New York, N. Y. SEELIG, Lester (Af 1925) Head Engrg. Dept., Museum of Science & Industry, Jackson Park, and (for mail) 725 Irving Park Rd., Chicago. III. SEICEL, Lawrence J. (7 1939) Test Engr., Cleveland Electric Illuminating Co., Cleveland, and (for mail) 350 E. 211th St., Euclid, O. SETTER, J. Earl* (Af 1928) Asst. Mgr. in Charge of Dist. Steam Sales (for mail) Consolidated Gas, Electric Light & Power Co., 500 Lexington Bldg., and 7117 Bristol Rd., Baltimore, Md. SEK1DO, Kunisuke (Life Member; Af 1903) Consulting Engr. (for mail) 19 Momozono, Nakano, Tokyo, Japan. `' SELIG, Ernest T., Jr. (Af 1936) Registered Professional Engr. and Industrial Fellow (for mall) Mellon Institute of Industrial Research, 4400 Fifth Ave., and 6609 Woodwell SL, Squirrel Hill, Pittsburgh, Pa. SELLMAN, Nils T. (Af 1922) Asst. Vice-Pres., Consolidated Edison Co. of New York, Inc., 4 Irving Place, New York, N. Y. SELTZER, Paul A. (7 1938) Engr., Bryant Air Conditioning Corp., 915 N. Front St., Philadel phia, and (for mail) 154 E. Marshall Rd.. Lansdowne, Pa. SENIOR, R. L. (Af 1925) Pres, (for mail) R. L. Senior, Inc., 103 Park. Ave., New York, and 10 Cherry Ave., New Rochelle, N. Y. SESSLER, Robert E. (5 1938) 52 Fountain Rd.. Arlington, Mass. SETTELMEYER, James T. (A 1940; 7 1937) Instructor in Refrig. & Air Cond., Essex County Vocational Schools, 294 Norfolk Si., Newark, and (for mail) 332 N. Maple Ave., East Orange, N. J. SEVERNS, W. H.* (Af 1933) Prof. Mech. Engrg. (for mail) University of Illinois, and 609 Indiana, Urbana, III. SEYFANG, William G. (if 1939) Managing Engr., Div. of Plant, Board of Education, 814 City Hall, and (for mail) 116 Dorchester Rd., Buffalo, N. Y. SEYMOUR, James E. (A 1937) Partner & Mgr., Lee & Seymour Warm Air Htg. & Sheet Metal Works, 346 Russell St., and (for mail) 208 Lakewood Blvd., Madison, Wis. SGAMBATI, Anthony P. (5 1939) Student, Carnegie Institute of Technology (for mail) 5029 MoTewood PL, Pittsburgh, Pa., and 3 Spencer St., Youngstown, O. SHAER, I. Ernest (A 1934) Treas. and Sales Mgr., Capitol Engineering Co., 71 Rogers St., Cam bridge, and (for mail) 43 Ormond St., Dor chester, Mass. . SHAFER. W. P. (S 1939) Student Engr., Trane Co., 108 N. 9th St., La Crosse, Wis. SHAFFER, Chester E. (Af 1937) Research Engr. (for mail) Koppers Co., Kearny, and 2801 Hudson Blvd., Jersey City, N. J. SHANKLIN, Arthur P. (Af 1929) Dist. Mgr. (for mail) Carrier Corp., 12 S. 12th St., Philadelphia, and 40 Amherst Ave., Swarthmore, Pa. SHANKLIN. John A. (Af 1928) Vice-Pres. & Treas. (for mail) West Virginia Heating & Plumbing Co., 233 Hale St., and 1507 Quarrier St., Charleston, W. Va. SHAPIRO, Charles A. (7 1938) Sales Engr., Johnson Service Co., 2853 N. 12th St., and (for mail) 2041 N. Wanamaker St., Philadelphia, Pa. SHAPIRO, Maurice M. (7 1937) Sales Engr.. Sidles Co., Airtemp Div., 1228 "P" St., and (for mail) 2145 *`N" St., Lincoln, Nebr. SHARP, Henry C. (Af 1935) Sales Repr., Herman Nelson Corp., and (for mail) 7442 Melrose St., St. Louis, Mo. ' SHARP, John E. (A 1939) Owner (for mail) Springfield Stoker & Heating Co., 215 N. Fifth St., and 1529 W. Grand S., Springfield, 111. SHARP, John R. (A 1937) Supervisor. Htg. and Air Cond. Reprs., Bergen Div., Public Service Electric & Gas Co., 235 Main St., Hackensack, and (for mail) Maple St., Haworth, N. J. SHAW, Burton E.* (A 1930; 7 1934) Research Chief (for mail) Penn Electric Switch Co.. Goshen, and Bristol. Ind. SHAW, Charles G. (A 1936) Engr. and Prop., Shaw Engineering Co., Port Arthur, Tex. SHAW, Norman J. H. (Af 1927 ; 7 1925) Barnes & Jones. Inc., 128 Brookside Ave., Jamaica Plain, and (for mail) 37 Benjamin Rd.. Arlington, Mass. SHAW, John A. (Af 1938) General Elec. Engr. (for mail) Canadian Padfic Railway Co., Windsor Sta., Montreal, and 448 Lansdowne Ave.; Westmount, P. Q., Canada. SHAWLIN, Walter C. (A 1931) Mgr., Industrial Air Cond., Northwestern Ventilation Co., 2540 West Wells St., Milwaukee, Wis. SHEA, Michael B. (Af 1921) Sales Dept, (for mail) American Radiator & Standard Sanitary Corp.. 8019 Jos. Campau, and 4080 Blaine St., Detroit, Mich. SHEARER, William A., Jr. (5 1939) Student. Carnegie Inst, of Technology, Pittsburgh, and (for mail) 407 Sixth Ave., New Kensington, Pa. SHEARS. Matthew W. (Af 1922) Engr. (for mail) C. A. Dunham Co., Ltd., 1523 Davenport Rd.," and 39 Sylvan Ave., Toronto, Ont., Canada. SHEFFIELD, Raymond A. (Af 1937) Prop., Air Conditioning Engineering Co., Cambridge, and (for mail) 84 Governor Winthrop Ave., Somer ville, Mass. ' SHEFFLER, Morris (Af 1921) Pres, (for mail) Sheffler-Gross Co., 1000 Drexel Bldg., Phila delphia, and 419 Chapel Rd., Melrose Park,' Montgomery Co., Pa. SHELDON, Nelson E. (Af 1927) Dist. Mgr. (for mail) Carrier Corp., 302 S. Geddes St., Syracuse, and 41 Lanark Crescent, Rochester, N. Y. SHELDON, William D., Jr. (A 1936: 7 1934) Chief Engr., Sheldon's, Ltd., and (for mail) Cedar St., Galt, Ont., Canada. SHELEY, Earle D. (Af 1937) Pres, (for mail) Glanz & Killian Co., 1761 W. Forest Ave., Detroit, and Box 243, Birmingham, Mich. SHELNEY, Thomas (Af 1931) Pres.. Pierce Blower Corp.. 105 Brayton St.. Buffalo. N. Y. 60 ROLL OF MEMBERSHIP SHENK, Donald H. (Af 1934) Assoc. Prof. Mech. Engrg. (for mail) Clemson Agriculture College, Riggs Hall, Clemson, S. C. SHEPARD, John deB. (Af 1937; 7 1929) Air Cond. Repr. (for mail) Consolidated G&s Electric Light & Power Co., Lexington Bldg., Room 406. and 4823 Keswick Rd., Baltimore, Md. SHEPPARD, F. A. (Af 1918) Salesman (for mail) Johnson Service Co., 1031 Wyandotte St., and 27 East 70th St., Kansas City, Mo. SHEPPERD, Parker D. (A 1940; 7 1938) Branch Mgr. (for mail) Johnson Service Co., 17 Metairie Court, New Orleans, La. SHERBROOKE. Walter A. (Af 1938) Grinnell Co., 29-50 Northern Blvd., Long Island City, and (for mail) 143 Main St., Tottenville, S. I., N. Y. SHERET, Andrew (Af 1929; A 1925) Pres, (for mail) Andrew Sheret, Ltd., 1114 Blanshard St., and 1030 St. Charles St., Victoria, B. C., Canada. SHERMAN, Ralph A.* (Af 1933) Supvr., Fuels Div. (for mail) Battelle Memorial Institute, 505 King Ave., and 1893 Coventry Rd., Columbus, O. SHERMAN, Victor L. (Af 1935) Assoc. Prof. Mech. Engrg., Lewis Institute, 1951 W. Madison St., Chicago, and (for mail) 643 Hillside Ave., Glen Ellyn, 111. SHERMAN, W. P. (Af 1937) Commercial Branch Engr. (for mail) York Ice Machinery Corp., P. O. Box 2210, Atlanta, and 208 Michigan Ave., Decatur, Ga. SHERWOOD, Laurence T. (Af 1937) Glass Tech nologist, Pennsylvania Wire Glass Co., Dunbar, Fayette Co., Pa. SHIELDS. Carl D. (7 1937: 5 1936) Engrg. Dept, (for mail) U. S. Rubber Co.. 6600 E. Jefferson, Detroit, and 1167 Kensington Rd., Grosse Pointe, Mich. SHILLING, Howard C. (A 1936) Sales Engr. (for mail) Barber-Colman Co., 221 N. LaSalle St., and 7068 N. Paulina St., Chicago, 111. SHIPLEY, Sylvanus C. (Af 1938) Cost Engr.. (for mail) Minneapolis-Honeywell Regulator Co., 2753 4th Ave., S., and 1550 East River Terrace, . Minneapolis, Minn. SHIRLEY, William B. (Af 1937) Sales Mgr. (for mail) Lennox Furnace Co., Inc., and Ward Apartments,' Marshalltown, la. SHIVERS, Paul F. (Afl930) Chief Engr. (for mail) . Minneapolis-Honeywell Regulator Co., W. Canal St,, and 75 W. Maple St., Wabash. Ind. SHODRON, John G. (Af 1921) Prof., Marquette University Engrg. School, and (for mail) 1810 West Wisconsin Ave., Milwaukee. Wi9. SHOEMAKER; Forrest F. (A 1936) Pres, and Mgr. (for mail) Air Conditioning Co., Inc., 1136 S. Peoria, and 2412 Exist 22r.d St., Tulsa, Okla. SHORB, Will A. (Life Member; Af 1909) Dist. Mgr., Decatur Pump Co., Decatur, 111., and (for mail) 47 N. Lime St., Apt. 6, Lancaster. Pa. SHORE, David* (7 1938) Research Engr. (for mail) A.S.H.V.E. Research Laboratory, 4800 Forbes St., and 969 Flemington St., Pittsburgh, Pa. SHROCK, John H. (Af 1924) Vice-Pres. (for mail) New York Blower Co., and 1002 Indiana Ave., LaPorte, Ind. SHUMAN, Laurence (Af 1939) Mech. Engr., . U. S. Housing Authority, Washington, D. C., and (for mail) 8367-16th St., Silver Spring, Md. SHULTZ, Earle (A 1919) Mgr. (for mail) Com mercial National Safe Deposit Co., 72 West Adams St., and 5555 Sheridan Rd., Chicago, 111. SIDELL, Philip A. (7 1938; 5 1937) Gale Prod. Div. (for mail) Outboard Marine & Mfg. Co., and 456 N. Cherry St., Galesburg, III. SIEBS, Claude T. (A 1927) (for mail) Bell Telephone Labs., Inc., 463 West St., New Yorx, N. Y., and 185 Kent Place Blvd., Summit. N. J. SIEGEL, Daniel E. (5 1938) Estimator, Guaran teed Heating & Engineering Co., 1923 Olive St., St. Louis, and (for mail) 7710 Wise Ave., Rich mond Heights, Mo. SIEGEL, Roy C. (A 1939) Owner (for mail) International Chimney Co., 503 EUicott Sq., and 243 Norwalk Ave.. Buffalo. N. Y. SIEGEL, William A. (Af 1937) Field Supt., York Ice Machinery Corp., 117 South Uth St., St. Louis, and (for mail) 3333 Cambridge, Maple wood. Mo. SIGMUND, R. W. (Af 1932) Dist. Mgr. (for mail) B. F. Sturtevant Co., 913 Provident Bank Bldg., and 130 E. Auburn, Cincinnati. O. SILBERSTEIN, Bernard G. (Af 1937) Dist. Mgr. (for mail) Ilg Electric Ventilating Co., 622 Broadway, and 814 East Mitchell Ave.. Cin cinnati, O. SILVERA, Americo (7 1939) Engr., Refrig. Dept., Viana's Auto Supply (for mail) P. O. Box 116, and House Silvia. San Nicholas, Aruba, Nctherland West Indies. SIMKIN, Milton (71936; 51933) Engr.. BuensodStacey Air Conditioning, Inc., 60 E. 42nd St.. New York, N. Y., and (for mail) 103 Brighton Ave., Perth Amboy, N. J. SIMONS, Byron C. (Af 1938) St. Louis Branch Mgr. (for mail) Minneapolis-Honeywell Regu lator Co., 3033 Locust Blvd., St. Louis, and 20 Orchard Ave., Webster Groves. Mo. SIMONS. Edward W. (Af 1938) Engr., Redwood Manufacturers Co., 1600 Hobart Bldg., and (for mail) 2418-30th Ave., San Francisco, Calif. SIMONSON, George M. (Af 1937) Consulting Engr. (for mail) 74 New Montgomery St., San Frandsco, and 20 Loreta Ave.. Piedmont. Calif. SIMPSON, W. K. (Af 1919) Vice-Pres. (for mail) Hoffman Spedalty Co., and 9 Sands St., Waterbury. Conn. SINGLETON, John H. (A 1937) Gen. Mgr. (for mail) Annas Heat & Cold, Inc., 13 N. Perry, and 66 Franklin Blvd., Pontiac, Mich. SKAGERBERG, Rurcher (Af 1924 ; 7 1921) Sr. Mech. Engr., U. S. Housing Authority, Wash ington, D. C., and (for mail) 2811 Holly, Alex andria, Va. SKELLEY, Jerome H. (A 1938) Mfrs. Agent. 4101 E. Ellsworth Ave., Denver, Colo. SKIDMORE, John G. (A 1937; 7 1930) Sales Engr., Almirall & Co., Inc., 53 Park PI., New York, and (for mail) 5101-39lh Ave., Long Island City. L. I.. N. Y. SKINNER. Henry W. (Af 1920) Consulting Engr., 4816 DeTter St., Fort Worth, Tex. SKLAREVSKI, Rimma (A 1940; 7 1936) Mech. Engr., Brown Instrument Co., Wayne & Roberts Aves., Philadelphia, Pa., and (for mail) 226 E. University Parkway. Baltimore, Md. SKLENARIK, Louis (A 1937; 7 1928) 305 East 72nd St.. New York. N. Y. SLAWSON, Lloyd E. (A 1938) Mgr., Temperature Control Dept., Barber-Colman Co., 3030 Eudid Ave.. Cleveland, O. SLEMMONS, John D. (Af 1937) Branch Mgr., American Blower Corp., Columbus, and (for mail) Rte. 2, Wilson Rd., Worthington, O. SLUSS, Alfred H.* (Af 1935) Prof. Mech. Engrg., . University of Kansas, and (for mail) 827 Missis sippi Ave., Lawrence, Kan. SLUTSKY, David J. (5 1939) Student, Carnegie Institute of Technology, and (for mail) 4929 Forbes St.. Pittsburgh, Pa. ' SMAK, Julius R. (A 1934) Supt. of Service Dept., Crane Co., South Ave., and (for mail) 3135 Park Ave., Bridgeport. Conn. SMALL. Bartlett R. (Af 1938; A 1937 ; 7 1932) Industrial Engr. (for mail) Aluminum Co. of America, SOI Gulf Bldg., and 34 Hillman St., Brentwood, Pittsburgh, Pa. SMITH, Elmer G.* (Af 1929) Assoc. Prof, of Physics (for mail) Agricultural & Mechanical College of Texas, Department of Physics, College Station. Tex. SMITH, Card W. (Af 1927) Sales Engr., Premier Furnace Co., Dowagiac, Mich., and (for mail) 1131 Guilford St., Huntington, Ind. SMITH, Milton S. (Af 1919) Treas. & Gen. Mgr. (for mail) Buensod-Stacey Air Conditioning. Inc., 60 East 42nd St., New York. N. Y., and 13 North Terrace, Maplewood, N. J. 61 r' HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 SMITH, Nelson J. (Af 1938) Air Cond. Design SOPER, H. A. (Af 1916) Vice-Pres. (for mail) Engr., Frigidaire Div., 300 N. Taylor St., American Foundry 8c Furnace Co., Washington Dayton. O. at McClun St., and 1122 E. Monroe St., Bloom SMITH, Reginald J. (Af 1936) Mgr., Smith & ' ington, 111. Elston, 71 Third Ave., and (for mail) 212 S. SOULE, Lawrence C.* (Af 1908) Secy, and Con Maple St.. Timmins. Ont., Canada. sulting Engr., Aerofin Corp., Syracuse, N. Y., SMITH, Roy L. (5 1939) Student. Carnegie and (for mail) Essex.Fells, N. J. Institute of Technology (for mail) 5010 Morewood PI.. Pittsburgh, Pa. SOUTHMAYD, Richard T. (7 1936) Salesman (for mail) American Blower Corp., 1302 Swetland SMITH, Stuart (A 1936) American Radiator & Bldg., Cleveland, and 65 Church St., Chagrin Standard Sanitary Corp., Connecticut & S St., Falls, O. N. W., Washington. D. C., and (for mail) 6922 SPALL, Edward G. (A 1939) Sales Engr., Power- Fairfax Rd.. Bethesda, Md. SMITH, Walter H. (Af 1939) Chief Engr. (for lite Devices, Ltd., Penn Electric Switch Div., 171 John St., and (for mail) 3 Thornhill Ave., mail) The T. Eaton Co., Ltd., Engineers Office, 190 Yonge St., and 7 Kingscourt Dr., Toronto, Ont., Canada. Toronto, Ont., Canada. ' SPARK, William (Af 1938) Mgr., Insulation Dept, (for mail) Atlas Asbestos Co., Ltd., 110 SMITH, Wilbur F. (Af 1920) Consulting Engr., McGill St., and 6171 Sherbrooke St., W., W. M. Anderson Co., 600 Schuylkill Ave., Pitts Montreal, P. Q., Canada. burgh. and (for mail) 709 Braeburn Lane, Penn SPARKS, James D. (A 1937) Northwest Repr.', Valley, Narberth P. O., Pa. SMITH, William D. (Af 1937; A 1935) Pres, (for mail) Bryant-Smith, Inc., 2153 Prospect Ave., Cleveland, and 3265 Enderby Rd., Shaker Heights, O. SMITH, William O. (A 1937) Pres, (for mail) Smith Automatic Heat Service Co., 19250 John R St., Detroit, and 343 E. Maplehurst, Femdale, Mich. SMOOT, T. H. (Af 1935) Gen. Mgr. & Chief Engr., Fluid Heat Div., Anchor Post Fence Co., 6500 Eastern Ave., and (for mail) 1302 Southview Rd., Baltimore, Md. Ilg Electric Ventilating Co. (for mail) 7331 W. Green Lake Way, Seattle, Wash. , SPECKMAN, Charles H. (Af 1918) Consulting Htg. and Vtg. Engr., Room 375, Philadelphia, Bourse, Philadelphia, Pa. SPELLER, F. N.* (Af 1908) Advisory Engr. (for mail) National Tube Co., P. O. Box 266,' Frick Bldg., and 6411 Darlington Rd., Pittsburgh, Pa. SPENCE, Morton R. (7 1934) Asst. Purch. Agt. (for mail) Runelle 8c Spence Mfg. Co., 445 N. Fourth St., and 709 E. Lexington Blvd., Milwau kee, Wis. SPENCE, Robert A. (7 1937) Asst, to Supt., Engrg. Dept., Harvard University, Lehman Hall, SMYERS. Edward C. {A 1933) Sales Engr., Barber-Colman Co., 1013 Penn Ave., Wilkiris- burg, and (for mail) 148 Jamaica Ave., West Cambridge, and (for mail) 37 Davis Rd., Bel mont, Mass. SPENCER, Dean (A 1937) Commercial Mgr. (for View, Pittsburgh, Pa. mail) Brown Electric Division, Brown Supply SNAVELY. A. Bowman (Af 1937) Chief Engr., Co., 120 E. Grand, and 3110 Northwest 23rd, Hershey Chocolate Corp., Hershey, Pa. Oklahoma City. Okia. SNAVELY, Earl R. (Af 1937) Tech. Dir., New York Technical Inst., 108 Fifth Ave., New York, N. Y., and Sales Dept., Thomas A. Edison, West SPENCER, J. Boyd (Af 1935) Pres. 8c Treas. (for mail) Spencer Air Conditioning Co., 2936 Pillsbury Ave., and 2215 Newton Ave., S.. Minneapolis, Orange, and (for mail) 222 Victory St., Roselle, N. J. SNYDER, Jay W. (Af 1917) Member of Firm (for mail) Snyder 8c McLean, 2308 Penobscot Bldg., and 8987 Martindale Ave., Detroit, Mich. SNYDER, Joseph S. (A 1925) Sales Repr., Detroit Lubricator Co., 1807 Elmwood Ave., Buffalo, and (for mail) 9 Knowlton Ave., Ken- more, N. Y. ' SOBEL, Frank {S 1939) Student, New York Technical Inst., 108 Fifth Ave., and (for mail) 745 E. 175th St.. New York, N. Y. . Minn. SPENCER. Roland M. (A 1940; 7 1934) Branch Mgr. (for mail) The Powers Regulator Co., 329 M 8c M Bldg., and 3010 Blodgett. Houston,. Tex. SPENCER, Warner E. (A 1938) Sales Repr. (for mail) National Radiator Co., 220 Delaware Ave., Buffalo. N. Y. SPIELMANN, Gordon P. (A 1931; 7 1923) VicePres. (for mail) Harrison-Spielmann Co., 480 Milwaukee Ave., Chicago, and 730 N. Prospect Ave.. Park Ridge, -1U-- __ SPIELMANN, Harold J. (Af 1933) Air Cond. SODEMANN, Paul (Af 1926; 7 1920) Sales Engr., Sodemann Heat 8c Power Co., 2306 Delmar Blvd., Engr., Vilter Mfg. Co., 230 W. Superior SL, Chicago, and (for mail) 507 Elmore Ave., Park and (for mail) 4136 Farlin Ave., St. Louis, Mo. Ridge. 111. . SODEMANN, William C. B. (Af 1919) Pres, (for SPITZLEY, Joseph H. (7 1939) Test Dept., mail) Sodemann Heat 8c Power Co., 2306 Delmar General Electric Co.. 1 River Rd., and (for mail) Blvd., St. Louis, and 7542 Teasdale Ave., 13 State St., Schenectady, N. Y. University City, Mo. - SPITZLEY, Ray L. (Af 1920) Pres. 8c Gen. Mgr. SOETERS, Matthew (Af 1937) Consulting Engr., (for mail) R. L. SpiUley Heating Co., 1200 W. 858 E. Grand Blvd., Detroit, Mich. Port St., Detroit, and 26 Renaud Rd., Grosse SOGG, Allen (A 1937) Sales Engr., Strong, Pointe Shores, Mich. ' Carlisle 8c Hammond Co., 1392 W. Third St., SPOERR, Frank F. (7 1937) Chief Engr., Hearn- Cleveland, and (for mail) 3084 E. Derbyshire ens, So. Warren 8c E. Front St., Trenton, N. J.. Rd.. Cleveland Heights. O. and (for mail) 140-19 Queens Blvd., Jamaica. SOLSTAD, Lester L. (7 1936) Htg. Engr. (for L. I., N. Y. mail) Austin Sheet Metal Works, 5109 W. SPOFFORTH, Walter (Af 1930) Chief of Mech. Chicago, and 5128 Blackstone, Chicago, 111. Services, U. S. Penitentiary, McNeil Island, and SOLZMAN. Isel l. {A 1937) Owner (for mail) (for mail) 615 N. Ainsworth Ave., Tacoma, Pasol Engineering Co., 532 World Herald Bldg., Wash. and 2714 North 55th St., Omaha, Nebr. SPREKELMEYER, J. M. (Af 1938) Mgr. (for SOMERS, William S. (Af 1938; A 1928; 7 1926) Chief Engr., Lamneck Products, Inc.,416 Dublin mail) General Engineering Corp., 1014`Jennings Ave., and 1912 Benhali Court, Fort Worth, Tex. Ave., and (for mail) 2229 Coventry Rd., Colum SPRING, Claude L. (A 1938) Htg. Engr., Dcs bus. O. ' Moines Stove Repair Co., 107 S. W. 2nd Ave., SOMMERFIELD, Sumner S. (7 1936) (for mail) and (for mail) 3840 Columbia Ave., Des Moines, 5705 School St., Chicago, 111. la. SOMMERS. William J. (Af 1937) Sales Repr.. SPROULL, Howard E. (Af 1920) Div. Sales Mgr. llg Electric Ventilating Co., 505 Delaware Ave.. (for' mail) American Blower Corp., 1005-6 Buffalo, and (for mail) 150 Stillwell Ave.. American Bldg., and 3588 Raymar Drive, Kenmore, N. Y. Cincinnati, O. 62 ROLL OF MEMBERSHIP SPURGEON, Joseph H. (Af 1924) Salesman (for . mail) Spurgeon Co., 5203 General Motors Bldg., and 17215 Pennington Drive, Detroit, Mich. SPURNEY, Felix E. (A 1938) Bldg. Mgr., Federal Reserve Bldg., 20th 8c Constitution Aves.,N. W., Washington, D. C., and (for mail) 28 W. Balti more St., Kensington, Md. STACEY, Alfred E., Jr.* (Af 1914) Vice-Pres., Buensod-Stacey Air Conditioning, Inc., 60 East 42nd St., New York, N. Y., and (for mail) 35 Wooton Rd., Essex Fells, N. J. STACK, Arthur E. (A 1935) Asst. Mgr. of Utilization Dept., Washington Gas Light Co. . of D. C., 411 10th St., N. W.. Washington. D. C., and (for mail) 911 Gist Ave., Silver Spring, Md. STACY, Loyd D. (A 1936) Sales Engr., Ilg Electric Ventilating Co., 222 N. LaSalle St., Chicago, and (for mail) 8423 Monticeilo Ave., Evanston, 111. STACY, Stanley C. (Af 1931) Mech. Engr. (for' mail) Board of Education, 13 S. Fitzhugh St., and 531 Wellington Ave., Rochester, N. Y. STAFFORD, J. Fuller (A 1938) Owner, T. Fuller Stafford Steam Specialties, 519 N. Snelling Ave., St. Paul, and 2925-33 Ave., S., Minneapolis, Minn - STAFFORD, Thomas D. (A 1937) Secy.-Mgr., Alexander-Stafford Corp.. 313-19 Allen St., N. W., and (for mail) 954 Ogden Ave., Gran d Rapids, Mich. ' STAHL, Walter A. (Af 1938) Operating Engr., Real Estate Div., Marshall Field 8c Co., 222 Bank Dr., Chicago, and (for mail) 2504 Harrison St., Evanston, 111. STALB, Joseph G. (A 1934) Mgr., Air Cond. Div., Reynolds Coro., 19 Rector St., New York, and for mail) 149 Columbia Heights, Brooklyn, N. Y. AMMER, Edward L. (Af 1919) Supt. Htg. and Vtg., Board of Education, Ninth and Locust Sts., and (for mail) 4430 Tennessee Ave., St. Louis, Mo. STANDRING, Ronald A. (7 1938) Htg. Designer, Gurney Foundry Co., Ltd., 100 Principal St., St. Laurent (near Montreal) and (for mail) 2358 Leclaire St., Maisonneuve, Montreal, P. Q., ' Canada. STANFIELD, Richard E. (7 1938) Industrial Engr. (for mail) Nebraska Power Cp., 723 Electric Bldg., and 5013 Cuming St., Omaha, Nebr. STANGER, R. B. (Af 1920) Prop, (for mail) Robinson 8c Stanger, Empire Bldg., Pittsburgh, and Middle Rd., Gienshaw, Pa. . STANGLAND, B. F. (Charter Member) (2nd Vice- Pres., 1908; Board of Governors, 1905-1906-1909; Board of Mgrs., 1895-1899; Council, 1896-1897) Retired Htg. 8c Vtg. Cons. 8c Constr. Engr., Howard 8c Morse, New York, and (for mailj Kendall, N. Y. . 1 STANLEY, Robert L. (Af 1938) Engr., Crown Furnace Sc Supply Co., 114 W. Union St., Pasadena, and (for mail) 2518 Dearborn Drive, Los Angeles, Calif. STANNARD, J. M* {Life Member; Af 1906) Pres, and Treas. (for mail) Stannard Power Equipment Co., 53 W. Jackson Blvd., Chicago, and 1402 Elinor Place, Evanston, 111. STANTON, Harold W. (Af 1937) Commercial . Engr. (for mail) Iowa-Nebraska Light 8c Power Co., and 2807 Washington St., Lincoln, Nebr. STARK, Clarence E. {A 1939) Vice-Pres., Mont clair Plumbing Supply Co., 83-101 Walnut SL, Montclair, and (for mail) 237 Sherman Ave., Glen Ridge, N. J. STARK, W. E.* (Af 1926) Regional Mgr., The Bryant Heater Co.. 17825 St. Clair Ave., Cleve land, and (for mail) 1875 Rosemont Rd., East ' Cleveland, O. STASZESKY, Francis M. (S 1938) Student (for mail) Massachusetts Institute of Technology Dormitories, Cambridge, Mass., and 10 Roselawn, Wilmington, Del. STEEL, R. Justin (A .1938) Engr. (for mail) Wilmington Auto Sales Co., 221 West Tenth St., Wilmington, and 165 W. Main St., Newark, Del. STEELE, John B. (Af 1932) Chief Operating Engr., Winnipeg School Board, Ellen and William Ave., and (for mail) 184 Waterloo St., Riverheights, Winnipeg, Man., Canada. STEENKAMP, Willem {S 1938) Box 12. Sheepmoor, Transvaal, Union of South Africa. STEFFNER, Edward F. (A 1937; 7 1934) Htg. and Air Cond. Engr., Henry Furnace 8c Foundry Co., 3471 East 49th St., Cleveland, and (for mail) 11016 Langton Ave., Garfield Heights, O. STEGGALL, Howard B. {A 1934) Branch Mgr. (for mail) United States Radiator Corp., 941 Behan St., and 1166 Murray Hill Ave., Pitts burgh, Pa. STEINER, Theodore J. (A .1938) Cons. Engr., 2100 S. Orange Dr., Los Angeles. Calif. STEINHORST, T. F. (Af 1919) Pres, (for mail) Emil Steinhorst 8c Sons, Inc., 612 South St., and (for mail) 1664 Brinckerhoff Ave., Utica, N. Y. STEINKE, Bernard J. (7 1940; 5 1937) Htg. and Vtg. Engr., Bernard H. Steinke 8c Son. 1104 East 180th St., New York, N. Y.. and (for mail) 17 Westervelt Place, West Englewood, N. J. STEINMETZ, C. W. A. (Af 1934) Mgr. of Newark Office (for mail) American Blower Corp., 249 High St., Newark, and 50 Oakwood Ave., Bogota, N. J. STELLWAGEN, Frank G. (A 1937) Salesman, Fitzgibbons Boiler Co., Inc., 101 Park Ave., New York, and (for mail) 8637-77th, Wood- haven, L. I., N. Y. STE-MARIE, Gaston P. (Af 1930) Examiner Technician (for mail) Department of Labour, Provincial Government, 97 Notre-Dame St., East, and 5329 Duquette Ave., N. D. G., Montreal, P. Q., Canada. STENCEL, R. Arthur (Af 1938) Chief Engr., Canadian Ice Machine Co., Ltd., 65 Villiers St., and (for mail) 45 Willowbank Blvd., Toronto, Ont., Canada. STENGEL, Frank J. (A 1935) Secy, (for mail) R. F. Stengel 8c Son, 76 Rosehill PL, and 723 Stuyvesant Ave., Irvington, N. J. STEPHENSON, L. A. (Af 1917) Mgr. (for mail) The Powers Regulator Co., 409 East 13th St., and 801 West 57th Terrace, Kansas City, Mo. STERMER, Clarence J. (Af 1936) Engr., Crane Co., 836 S. Michigan Ave., and (for mail) 7839 Clyde Ave., Chicago, 111. STERNBERG, Edwin (A 1932; 7 1931) Air Cond. Engr., Armo Cooling 8c Ventilating Co., 30 West 15th St., and (for mail) 115 East 92nd St., New York, N. Y. STERNE, Cecil M. (A 1934) Chief Engr., Metro politan Refining Uo., Inc., 23-28-50th Ave., Long Island City, L. I., N. Y. STERNER, Douglas S. (A 1940; 7 1938; A 1936) Branch Mgr., Electrical Div., Barber-Colman Co., 78 Baker St., N. W., Atlanta, Ga. STETSON, L. R. (Af 1913) Engr. (for mail) McMurrer Co., 303 Congress St., Boston, and 35 Bradfield Ave., Roslindale, Mass. STEVENS, Alfred L. (A 1939; 7 1938) Refriger ating Engr., MoIIenberg-Betz Machine Co., 20 Henry St., Buffalo, and (for mail) 45 Pasadena __Place, WiUiamsville, N. Y. ` STEVENS, Harry L. (Af 1934; A 1927 ; 7 1924) Secy.-Treas. (for mail) M. M. Stevens Co., 108 W. Sherman St., and 7 West 22nd St., Hutchin son, Kan. STEVENS, Kenneth M. (7 1936) Sales Engr. (for mail) The Powers Regulator Co., 409 East 13th and 4734 Summit, Kansas City, Mo. STEVENS, Wayne H. (A 1939) Engr. 8c Service Mgr. (for mail) Shellenberger, Gregg 8c Co., 2203 N. Prospect Ave., and 1609 E. Riverside PI., Milwaukee1, Wis. STEVENS, William R. (A 1934) Partner, L. E. Stevens Co., 626 Broadway, Cincinnati, O., and (for mail) 30 Chalfonte Court, Fort Thomas, Ky. STEVENSON, Melvin J. (Af 1935) Chief Design Engr. (for mail) Tropic-Aire, 4501 Augusta Blvd., and 7915 Euclid Ave., Chicago, 111. 63 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 STEVENSON, W. W. (M 1928) Steam Htg..Engr. (for mail) Allegheny Co. Steam Htg. Co., 435 Sixth Ave., and 1125 Lancaster Ave., Pitts burgh, Pa. STEWART. Charles W. (M 1919; A 1918) Asst. ' Secy, (for mail) Hoffman Specialty Co., Water- bury National Bank Bldg., and 21 Yates Ave., Waterbury, Conn. STEWART, Duncan J.* (M 1936; A 1930) Mgr. Electrical Div. (for mail) Barber-Colman Co., Drawer 99, and R. R. No. 4, Rockford, 111. STEWART, James P. (A 1940; 7 1937) Engr., Air Conditioning, Power Engineering Corp., 517 Brooks Bldg., Wilkes-Barre, and (for mail) 338 Maple Ave., Kingston, Pa. STEWART, John N. (A 1939) Smoke Inspector, District of Columbia, 306 District Bldg., and (for . mail) 2019 N St., N. W., Washington, D. C. STEWART, Wesley O. (A 1938) Branch Mgr. (for mail) Johnson Service Co., 153 West Ave.,34 and 192^$ Rodnay Dr., Los Angeles, Calif. STIEGLER, Alvin J. (A 1938) Owner (for mail) Valley Sheet Metal Works, 315 Main St., and 319 Monroe St., Neenah, Wis. ` STILES, Gordon S. (7 1936) Sales Engr. (for mail) Airtemp Div., Sidles Co., 118 Tenth St., and 206-1 Uh St., Des Moines, la. STILL. Fred R.* (Life Member; M 1904 ^Presi dential Member) (Pres., 1918; 2nd Vice-Pres.. 1917; Council, 1916- 1919) Vice-Pres. in charge of Export (for mail) American Blower Corp., 50 West 40th St., New York, and 3457-82nd St., Jackson Heights, L. I., N. Y. STILLER, F. W. (7 1933) Estimator (for mail) F. C. Stiller Co., 129 South Tenth St., and 138 West 49th St., Minneapolis, Minn. STINARD, R. L. (7 1934) Sales Engr., American Radiator & Standard Sanitary Corp., 32-04 Northern Blvd., Long Island City, L. I., N. Y., and (for mail) 1377 Boulevard East, West New York. N. J. STIRLING, Walter N. (Af 1939) Resident Repr., Messrs. J. & E. Hall, Ltd., c/o Jessop & Co., 93 Clive St., and (for mail) 63 Elliot Rd., Calcutta, India. STITES, Richard, Jr. (7 1937) Sales Engr. (for mail) Buffalo Forge Co., 2051 W. Lafayette, and 2170 E. Jefferson, Detroit, Mich. STOCK, Charles S. (M 1936) Dist. Repr.. The Herman Nelson Corp.. Rra. Il08-16th St., N. W,, Washington, D. C., and (for mail) 6752 Fairfax Rd., Bethesda, Md. STOCKWELL, William R. (Life Member M 1903;71901) Gen. Mgr., Mfg.Div., Weil-McLain Co.. Michigan City, Ind. STOKES, Alvin D. (M 1936) Engr., Adsco Building Contractors, 901-7th St., S. W., Wash ington, D. C.,-and (for mail) 4010 Eltendale Rd., Drexel Hill, Pa. STOKES, Arledge (7 1936) Air Cond. Engr. (for mail) Mehring and Hanson Co., 12 H St., N. E., Washington, D. C., and 320 N. Piedmont St., Arlington, Va. . STORCH. Clemens A. (M 1930) Sales Engr., Johnson Service Co., 1355 Washington Blvd., Chicago, and (for mail) 331 Cumnor Rd., Kenil worth, 111. STORMS, Robert M. (M 1936) Mech. Engr., Consulting Htg. and Vtg. (for mail) 816 West 5th St., Los Angeles, and 354 W. Wilson, Glen dale. Calif. STOTT, F. W. (M 1937) Sales Engr., C. A. Dunham Co., Ltd., 1139 Bay St., Toronto, and (for mail) 3 Palmer Ave., Oakville, Ont., Canada. STOTZ, Robert B. (7 1938) Sales Engr. (for mail) Frigidaire Div., General Motors Sales Corp., 675 Greenwood Ave., and 1702 Harvard Rd., Atlanta, Ga. STRAUCH, Paul C. (A 1934) Sales Engr.. The Henry Furnace & Foundry Co., S. 18th & Merre- man Sts., and (for mail) Cambridge Court Apts., 131 Edgewood Ave., Edgewood, Pittsburgh; Pa. STREATER, Edward C. (A 1939) Mgr. (for mail) L. E. Streater Lumber Co.. Spring Park, and Mound. Minn. STREVELL, R. P. (M 1934) Pres. & Treas. (for mail) The Wm. R. Hogg Co., Inc., 900 Fourth Ave., Asbury Park, and State Highway & Victor Place, Neptune, N. J. STRICKLAND, Albert W. (A 1929) Htg. & Vtg. Engr., Big Timber, Mont. STROCK, Clifford (M 1937; A 1929) Associate Editor (for mail) Heating & Ventilating, 148 Lafayette St.. New York, and 82-15 Britton Ave., Elmhurst, L. I., N. Y. STROMGREN, Sven G. (M 1938) Mgr. (for mail) Asea Electric, Ltd., 4 Lyon Range, and 14/1 Rowland Rd., Calcutta, India. STROUSE, Sherman W. (A 1934) Branch Mgr., The Trane Co., 493 Franklin St., and (for mail) 198 Lovering Ave., Buffalo, N. Y. STROUSE. Sidney B. {M 1921) Consulting Engr. (for mail) 500-529 Guarantee. Trust Bldg., and 22 S. Illinois Ave., Atlantic City, N. J. STRUNIN, Jay (4 1939; 7 1933) Engr. & Con tractor, Strunin PIbg. & Htg. Co., Inc. (for mail) 408 Second Ave., and 54 West 89th St., New York. N. Y. STUART, Milton C.* (M 1935) Prof, of Mech. Engrg. (for mail) Lehigh University. Mech. Engrg. Dept., and 505 Norway Place, Bethlehem, Pa. STUBBS, William C. (M 1934) Associate Naval ArchL, U. S. Government (for mail) Norfolk Navy Yard, and 37 Channing Ave., Ports mouth, Va. STURDY, Oswald C. (M 1938) Sales Engr. (formail) Foster Wheeler. Ltd., Commerce & Trans portation Bldg., and 193 Dunn Ave., Toronto, Ont.. Canadia. STURM, William (7 1937; 5 1936) Engr., Spencer Cooling & Air Cond. Co.. 413 S. Sixth St., and (for mail) 315-16th Ave., S. E., Minnear polis, Minn. SUDDERTH, Leo (7 1936) Sales Engr. (for mail) Johnson Service Co., Bona Allen Bldg.', and 1115 Los Angeles Ave., N. E., Atlanta, Ga. SULLIVAN, Charles J. (A 1938) Owner & Mgr., C. J. Sullivan, 5456 Baltimore Ave.. and (for. mail) 5470 Baltimore Ave., Philadelphia, Pa. SUMMERS, Clarence G. (A 1938) Dist. Mgr.. Ilg Electric Ventilating Co., 2144 Madison Ave., Toledo, O. SUMMERS. Ernest T. (4 1930) Mgr. (for mail) E. T. Summers 8c Co., 192 Pacific Ave., and 47 Newcastle Apts.. Winnipeg, Man., Canada. SUNDERLAND, Richard P. (4 1938) Pres, (for mail) General Meters St Controls Co., 205 Wacker Drive, Chicago, and 936 Judson Ave., Evanston, 111. SUPPLE, Graeme B. (M 1934) Dist. Mgr. (for mail) American Blower Corp., 625 Architects & Builders Bldg., and 6224 Park Ave., Indianapolis. Ind. SUTCLIFFE, Arthur G. (M 1922; A 1918) Chief Engr., Ilg Electric Ventilating Co., 2850 N. Crawford Ave., and (for mail) 4146 N. SL Louis Ave., Chicago, III. SUTFIN, George V. (4 1937) Sales Engr. (for mail) American Blower Corp., 1005-6 American Bldg., and 3270 Hildreth Ave., Cincinnati, O. SUTHERLAND, David L. (4 1934) Pres, and Treas.. Sutherland Air Conditioning Corp., 15 N. Eighth St., and (for mail) 1815 Colfax Ave.. Minneapolis, Minn. SUTHERLAND, Floyd A. (M 1938) 403 Crest Ave.. Charleroi, Pa. ' SUTTER, Edgar E. (4 1936) Sales Engr.. Mueller Brass Co., Port Huron. Mich, and (for mail) 6705 Sixth St., N. W., Washington, D. C. - SWAIN, William L.. (M 1939) Dir., Messrs. Young, Austen & Young, Ltd., 35 Uphill Rd., Mill Hill, London, N. W. 7, England. SWANEY, Carroll R. (M 1929 ; 7 1921) Co Partner (for mail) Gilbert Howe Gleason St Co., 28 St. Botolph St.. Boston, and 43 Clyde St., Newtonville. Mass. 1 ROLL OF MEMBERSHIP SWANSON, Donald F. (7 1938) Test Engr., Seegef Refrigerator Co., 850 Arcade St.. SL Paul, and (for mail) 4316 Bloom Ave., Minne apolis, Minn. SWANSON, Earl C. (4 1935) Vice-Pres.. Andersen Corp.. Bayport, Minn. SWANSON, Nils W. (4 1936) Salesman, Mc Donnell & Miller, 400 'N. Michigan Ave., and (for mail) 2746 Morse Ave., Chicago, 111. SWEENEY, Robert H. (4 1939) Sales Engr. (for mail) Minneapolis-Honeywell Regulator Co., 86 S. 26th St., Minneapolis, Minn-, and 2910 Voelkel Ave., Pittsburgh, 1%. SWENSON, J. E. (4 1930) Mgr., House Htg. Dept, (for mail) Minneapolis Gas Light Co., 800 Hennepin Ave., and 4853-14th Ave., S., Minneapolis, Minn. ' SWINGLE, Wayne T. (4 1938) Chief Engr.. F. Jaden Mfg. Co., Inc;, and (for mail) Y. M. C. A., Hastings, Nebr. SWISHER, Stephen G-, Jr. (M 1936; 4 1934) Branch Mgr. (tor mail) The Trane Co., 1835 N. 3rd St., and 1711 E. Dean Rd., Milwaukee, Wis. SYDOW, Louis J. (M 1936) Vice-Pres.. Grossen- bacher Steel Furnace Mfg. Co-. 9410 W. Milton Ave., and (for mail) 9456 Midland Ave., St. Louis, Mo. SYMONDS, Edward S. (M 1939) Mgr. (for mail) Abain Engineering. Ltd., 1 Devonshire Square, London, E. C. 2, and 84 The Ridgeway. Ching- ford, Essex. England. ' SYSKA, Adolph G. (M 1933) Consulting Engr. (for mail) Syska & Hennessy, 420 Lexington Ave., New York, and 3 Alden PI., Bronxvitle, N. Y SZEKELY, Ernest (M 1920) Vice-Pres. and Gen. Mgr. (for mail) Bayley Blower Co., 1817 S. 66th St., Milwaukee, and 6026 W. Washington Blvd., Wauwatosa, Wis. SZOMBATHY, L. R. (4 1930) Pres, (for mail) Ferguson Sheet Metal Works, 3^ N. Florissant Blvd.. Ferguson, and 3125 Hawthorne Blvd., St. Louis, Mo. T TAGGART, Ralph C.* (M 1912) Div. of Archi tecture, Dept, of Public Works, New York State, ! and (for mail) 14 Lyon Ave., Menands, Albany, N. Y. TAHR.Y, Mahmoud El (M 1939) Engr. in Charge (for mail) Carrier Egypt, S. A. E., 37 Sharia Kasr El Nil, Cario. Egypt. TALIAFERRO, Robert R.* (M 1919) Service Engr., Carrier Corp., 300 S. Geddes St., and (for mail) 714 Ostrom A^e., Syracuse, N. Y. TALLIANOS, Peter C. (4 1938) Mgr., The Egyptian Wireless Co., 36 Nebi Daniel SL, Alexandria, EgypL TALLMADCE, Webster (M 1924) Pres, (for mail) Webster Tallmadge & Co., Inc., 255 North 18th St., East Orange, and 7 Claremont Place, Mont clair, N. J. TANGER, Othon C. F. (4 1937) Dir., N. V. Technische Handelsmaatschappij "Renova" Rembrandtlaan 34, Arnhem, Netherlands. TAPLEY, Mark S. (M 1937) Htg., Vtg. and Air Cond. Engr., 3280 Holdrege SL, Lincoln, Nebr. TARR, Harold M. {M 1931) Htg. & Vtg. Engr., 21 Montague SL, Arlington Heights, Mass. v TASKER, C.* (M 1935) Research Fellow (for mail) Ontario- Research Foundation, 43 Queens Park, and 737 Avenue Rd., Toronto, Ont., Canada. ' - TAVERNA, F, F. (M 1928; A 1927;7 1924) Engr., . Raieler Corp., 129 Amsterdam Ave., New York, N. Y., and (for mail) 406-12tb St., Union City, N. J. * TAYLOR, Edward M. (4 -1934) Tech. Mgr. (for mail) Taylors. Ltd., 643 Colombo SL, and 51 Totara Rd.. Christchurch, New Zealand. TAYLOR, Fielding, Jr. (74938) Sales Engr. (for mail) American Machine & Metals, Inc., DeBothezat Ventilating Div., 100 Sixth Ave., New York, and 7105-37th Ave., Jackson Heights, L. I.. N. Y. TAYLOR, Harold J. (M 1937) Owner. Harold J. Taylor, Htg. & Vtg., 17514 Greenlawn Ave., Detroit, Mich. TAYLOR, Robert B. (7 1938) Sales Engr. (for mail) Buffalo Forge Co., 702 Tower Petroleum Bldg., and 3000 Yale Blvd., Dallas. Tex. TAYLOR, R. F. (M 1915) Consulting Engr. (for mail) 910 Bankers Mortgage Bldg., and 2332 Watts Rd., Houston, Tex. TAYLOR, Thomas E. (7 1937) Consulting Mech. Engr. (for mail) 307 Postal Bldg., and 7307 N. Wall Ave., Portland, Ore. TAZE, D. L. (M 1931) Dist. Mgr. (for mail) American Blower Corp., 1302 Swetland Bldg.. Cleveland, and 19412 Winslow Rd., Shaker Heights. O. TAZE, Edwin H. (M 1937) Branch Mgr. (for mail) American Blower Corp., 620 Court Square Bldg., Baltimore, and 28 Normal Terrace, Towson, Md. TEASDALE, Lawrence A. (M 1926) Engr., . University Service Bureaus (for mail) Yale University, 20 Ashmun SL, and 262 West Rock Ave., New Haven, Conn. TEELING, Geo. A. (M 1930) Consulting Engr. (for mail) 1 Columbia Place, Albany, and Box 81, Clarkesville, N. Y. TEMPLE, W. J. (M 1931) Engr., J. A. Temple Co., 108 Parkway, and (for mail) 1215 Real SL. Kalamazoo, Mich. TEMPL1N, Charles L. (Af 1921) Pres, (for mail) Carrier Atlanta Corp., 348 Peachtree SL, and (for mail) 781 Sherwood Rd., N. E., Atlanta. Ga. TENKONOHY, Rudolph J. (M 1923) 3650 Shaw Blvd., St. Louis, Mo. TENNANT, Raymond J. J. (4 1929) Engr. (for mail) Pittsburgh Business Properties. Inc., 2237 Oliver Bldg., and 301 Hazel Dr., Pittsburgh, Pa. TENNEY, Dwight (Af 1932) Pres. & Chief Engr. (for mail) Tenney Engineering. Inc.. 46 Farrand SL. Bloomfield, and 33 Summit Rd., Verona. NJ. TERHUNE, Ralph D. (4 1936) Sales Engr.. American Radiator & Standard Sanitary Corp.. ' 1747 Connecticut Ave., Washington, D. C., and (for mail) 4516 Highland Ave., Bethesda, Md. TERRY, Matson C. (Af 1936) Pres, (for mail) Certified Products Co., 136 Huron SL, and 3520 Island Rd., Toledo, O. ter WEEME, Albert (4 1938) Sales Engr.. N. V. Radiatoren, Singel 206-208, Amsterdam, C, and (for mail) Archimedesweg 13, Amsterdam, O. Holland. THEOBALD, Art (4 1937) Research Engr. (for mail) Payne Furnace & Supply Co., Inc., 336 N. Foothill Rd., Beverly Hills, and 116J S. Kings Rd., Los Angeles, Calif. THEORELL, Axel T. (M 1939) Civil Engr., Theorells Ingeniorsbyra, Skoldungagatan 4, and (for mail) Lokattsvagen 41, Appelviken, Stock holm, Sweden. THEORELL, Hugo G. T.* (Life Member; M 1902) Consulting Engr., Hugo Theorells Ingeniorsybra, Skoldungagatan 4, Stockholm. Sweden. THINN, C. A. (Af 1921) C. A. Dunham Co.. 450 - East Ohio SL, Chicago, IU. THOM, Arthur J. (7 1939) Sales Engr., Johnson Service Co., 507 E. Michigan SL, and (for mail) 3037 S. 39th SL. Milwaukee, Wis. THOM, George B. (M 1937) AssL Prof. Mech. Engrg., Swarthmore College, Swarthmore, Pa. THOMAN, Estelle O. (4 1938) Htg. & Air Cond. Engr. (for mail) Boot & Co., 115 Fulton SL, W.. and 403 College St., S., Grand Rapids, Mich. THOMAS, Arthur E. (7 1938) Contracts Mgr., Young, Austen & Young. Ltd., H35/36 Exchange Bldgs., Liverpool 2, and (for mail) `'Arten" 56,. Tbingwail Rd., Wavertree, Liverpool, 15, Eng land. THOMAS, Bernard A. (4 1927; 7 1923) Mgr., Htg. & Engrg. Dept., Crane Co., 1405 Twiggs SL. and (for mail) 405 E. Idlewild Ave., Tampa, Fla. THOMAS. Glegge (Af 1923) Mgr., Wash. Office (for mail) Clarage Fan Co., 723 Albee Bldg., Washington, D. C., and 7 W. Leland SL, Chevy Chase. Md. 65 v HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 THOMAS, L. G. Lee {M 1934) Vice-Pres, (for mail) Economy Pumps, Inc,, 1000 Weller Ave., and Anthony Wayne Hotel, Hamilton, O. THOMAS, Melvem F. {M 1909) Consulting Engr. (for mail) 24 Bloor St., W,, and 74 Rivercrest Rd., Toronto, Ont., Canada. THOMAS, Norman A. (M 1928) Pres., Thomas Heating Co.. 142 South 14th SL, La Crosse, Wis. THOMAS, Ralph C. (A 1938) Vice-Pres. & Mgr., Bonair Conditioning & Refrigerating Co., Inc., West Norfolk, and (for mail) 819 Westover Ave., - Norfolk, Va. THOMAS, Richard H. {Life Member; M 1920) Pres, (for.mail) Economy Pumps, Inc., 2522 W. Congress St., Chicago, and 426 Forest Ave., Oak Park, 111. THOMMEN, Adolph A. (A 1929) Air Cond. Fitting Mfr., John W. Thomson Co., 10316 S. Throop St., and (for mail) 3400 W. 61st Place, Chicago, 111. THOMPSON, Edward B. (A 1938) Htg. Engr., Cincinnati Gas & Electric Co., 4th & Main Sts., and (for mail)1198 Coronado Ave., Cincinnati, O. THOMPSON, Frank (M 1935) Gen. Supt.. Vulcan TOBIN, John F. (A 1934) Salesman (for mail) American Blower Corp., 228 N. LaSalle SL, and 11256 S. Artesian Ave., Chicago, III. ' TODD, Meryl L. (A 1940; J 1936) Meryl L. Todd, Mech. Engr. (for mail) 1111 Independence Ave., . and 100 Highland Blvd., Waterloo, la. ' TODD. Stanton W. (A 1939; J 1935) Sales Repr., American Radiator Co., 8019 Jos. Campau St., Detroit, and (for mail) 309 Paris, S. E,, Grand Rapids, Mich. . TOLHURST, George C. (M 1936) in Charge of Engr. Dept., Gumey Massey Co.. Ltd., 36 Principal St., and (for mail) 142 Blvd. St. Germain, St. Laurent (near Montreal) P. Q., Canada. TONRY, Robert C. (M 1936) Mgr. (for. mail) Wiedbusch Plumbing & Heating Co.. 511 First St., and 217 Fairmont Ave., Fairmont, W. Va. TOONDER, C. L. (M 1933) Asst. Mgr. Air Cond. Sales, Norge Div., Borg-Warner Corp., 670 E. Woodbridge, and (for mail) 13391 Marlowe, DetroiL Mich. TORNQUIST, Earl L. (A 1934) Test Engr. (for mail) Public Service Co. of Northern Illinois. Iron Works, Ltd., Pt. Douglas Ave., and (for 72 West Adams St., Chicago, and 465 Parkside mail) 543 Newman St., Winnipeg, Man., Canada. Ave., Elmhurst. 111. THOMPSON, Nelson S.* (Life Member; M 1917; TOROK, Elmer {M 1936) Supt. of Power (for 7 1897) 1615 Hobart St., N. W., Washington, . mail) North American Rayon Corp., and 203 D. C. West G St., Elizabethton, Tenn. THOMSEN, Nis B. {M 1938) Consulting Engr. TORR, Thomas W. (M 1933) Chief Engr.. Rudy (for mail) Baymond Corp., Victory Bldg., 21st Furnace Co., and (for mail) 205 Green St., Floor, Toronto, Ont., Canada. . THOMSON, Thomas N.* (Life Member; M 1899) Plbg. and Htg. Consultant, 37 Irwin Place, Huntington, L. I., N. Y. THORNBURG, Harold A. (M 1932; J 1929) 620 Murrell Blvd., Paducah, Ky. THORNTON, Thaddeus L. {M 1937) Main tenance Engr., Prudential Insurance, 96 Barclay St,, Newark, and (for mail) 37 Perry SL* Belle ville, N. J. THORNTON, W. B.* {M 1931) Engr., Carrier Corp., Merchandise Mart, and (for mail) 8314 Indiana Ave., Chicago, 111. THRUSH, Homer A. (M 1918) Pres., H. A. Thrush & Co., 21 East Riverside Drive, Peru, Ind. THULMAN, Robert K* {M 1938) Mech. Engr., Federal Housing Administration, Vermont and K Sts., N. W., Washington, D. C., and (for mail) 6505 Ridgewood Ave., Chevy Chase. Md. THUNEY, F. M. (A 1939; 7 1936) Application . Engr. (for mail) Wo;' E. Kingswell, Inc., 3707 Georgia Ave., N. W., Washington, D. C., and 202 Glenwood Rd., Bethesda, Md. TIDMARSH, Patrick M,.(M 1938) Vice-Pres. & Gen. Mgr., Tidmarsh Engr. Co., P. O. Box 2425, Tucson, Ariz. - TILLER, Louln (A 1935; S 1933) Air Cond. Engr. Oklahoma Gas & Electric Co.. 321 N. Harvey, and (for mail) 2712 Northwest 15th SL, Okla homa City, Okla. TILTON, Neil K. (A 1939) Pres, (for mail) May flower Air Conditioners. Inc., Duluth Ave. & East 7th St., and 876 Osceola Ave., St. Paul, Minn. TILTZ, Bernard E. (M 1930) Pres, (for mail) Tiltz Air Conditioning Corp., 230 Park Ave., New York, and 24 Barnum Rd., Larchmont, N. Y. . TIMMINS, W. W. {M 1937) Dist. Mgr. (for mail) Canadian Powers Regulator Co., Ltd., 344 University Tower Bldg., Montreal, and 351 Brock Ave., North, Montreal WesL P- Q.. .Canada. TIMMIS, Pierce (M 1920) Service Equip. Engr. (for mail) United Engineers & Constructors, Inc. 1401 Arch St., Philadelphia, and 202 Midland Ave., Wayne. Pa. TIMMIS, W. Walter {M 1933; A 1925) Vice-Pres. (for mail) Herske & Tiramis. Inc., 33 W. 60th SL, New York, and PleasantviUe, N. Y. TJERSLAND, AJf {M 1916; 7 1906) E. Sunde & Co., Ltd., Oslo, Norway. Dowagiac, Mich. TOULOUKJAN, Yeram (S 1939) Grad. Student, Massachusetts Institute of Technology, and (for mail) Graduate House, Massachusetts Institute of Technology, Cambridge, Mass. TOUTON, R. D. {M 1933) Tech. Director (for mail) Bayuk Cigars, Inc., Ninth and Columbia Ave., Philadelphia, and 19 Lodges Lane, Cynwyd, Pa. ' TOWER, Elwood S. (M 1930) Consulting Engr. (for mail) 213 Investment Bldg., and 5516 Wood- mont St., Pittsburgh, Pa. TOWLE, Philip H. (7 1938) Air Cond. Engr. (for mail) General Air Conditioning Co;, 1313 Jay St., and 942-42nd St., Sacramento, Calif.- TOWNE, Charles O. (J 1938) 3020 W. Ninth- Ave., Amarillo, Tex. TRACY, William E. (7 1937) S^les Engr. (for mail) B. F. Sturtevant Co., 404 Wrigley Bldg., Chicago, and Glen Ellyn. 111. TRAMBAUER, Charles W. (J 1936) Sales Engr., . Hoffman Specialty Co.,' 500 Fifth Ave., New York, and (for mail) 145-50-18th Ave., White- stone, L. I., N. Y. TRANE, Reuben N.* (M 1915) Pres, (for mail) The Trane Co., and 126 South 15th SL, La Crosse, Wis. TRAUGOTT, Mortimer (A 1930) (for mail) Bryant Air Conditioning Corp., 915 N. Front St., Philadelphia, and 8208 Westminster Rd.. Elkins Park. Pa. TRAWICK, Jack G. (M 1937) Dist. Repr. (for mail) Minneapolis-Honeywell Regulator Co., 1316 Comer Bldg., and 512 S. 47th SL, Birming ham, Ala. . TRAYNOR, Harry S. (7 1937) Engr., Carrier Corp., S. Geddes St., and (for mail) 594 Roberts Ave., Syracuse, N. Y. TREADWAY, J. Quentin (A 1936; J 1932) Dist. Sales Mgr. (for mail) Clarage Fan Co., 210 Reynolds Arcade, and 826 Winona Blvd., Rochester, N. Y. . TRELEAVEN, Herbert M. (J 1938) Junior Engr., Weathermakers (Canada) Ltd., 593 Adelaide St., W., and (for mail) 21 Glenfern Ave., Totonto, Ont., Canada. . TRENNER, Kelvin (A 1938) Dist Engr., Eastern Stokol Corp., 311 Ross St., Pittsburgh, Pa., and (for mail) 666 Roosevelt Ave., Warren, O. TRIGGS. Fred E. (M 1938) Mfrs. Agent. P. O. Box 1, H. P. Sta., and (for mail) 3901-2nd SL, Des Moines, la. 66 ROLL OF MEMBERSHIP TROSTEL, Otto A. (M 1935) Engr. (for mail) Kern Engineering Co., Inc., 161 W. Wisconsin Ave., and 3155 N. 7th St., Milwaukee, Wis. TROUP. John D. (M 1938) Managing Dir. (for mail) John D. Troup, Ltd., 90 High Holbom, London, W. C. 1, and 48 Plough Lane, Purley, Surrey, England. TRUITT, G. Scott (7 1937; S 1936) Production Dept., Bastian-Morley Co., Inc., and (for mail) 907 Indiana Ave., LaPorte, Ind. TRUMBO, Silas M. (A 1926) Sales (for mail) Buffalo Forge Co., 20 N. Wacker Dr., Chicago, and 921 Franklin SL, Downers Grove, 111. TRZOS, Otto A. (A 1940; 7 1938) Industrial Gas ' Engr., Consumers Power Co., 26 W. Lawrence St., and (for mail) 78H Murphy SL, Pontiac, Mich. TUCKER, Frank N. (M 1926) Field Engr., Ilg Electric Ventilating Co., 15 Park Row, New York, and (for mail) 239 Whaley SL, Freeport, L. I., N. Y. TUCKER, Leonard A. (M 1935) Service Sales Mgr., J. J. Pocock, Inc., 3lst & Jefferson Sts., Philadelphia, and (for mail) 518 Monroe Ave., Ardsiey, Pa. " TUCKER, Thomas T. (M 1938; A 1936) Chief Engr., Armor Insulating Co., 260 Peachtree SL, and (for mail) 3619 Old Ivy Rd., N. E., Atlanta, Ga. TUCKERMAN, George E. {M 1932) Mgr. (for mail) Anderson Conditioning Co., 600 Schuylkill Ave., Philadelphia, -and 502 Rodman Ave., Jenkintown, Pa. TUMPANE, James P., Jr. (S 1939) Student, Carnegie, Institute of Technology (for mail) 5029 Morewood PI., Pittsburgh, Pa., and Big Flats, N. Y. TUPPER, George B. (A 1930) Gen. Sales Mgr., National Standard Air Products Co., 325 W. Huron St., and (for mail) 5921 Kenmore Ave., Chicago, 111. TURK, Leonard (7 1940; S 1938) Maintenance & Construction Engr. (for mail) Firestone Tire & Rubber Co.. Firestone Park, and 771 Merriman Rd., Akron, O. TURLAND, Charles H. (M 1934; A 1930) Sales Engr. (for mail) R. E. Johnston Co., Ltd., 1070 Homer St., and 4553 W. 3rd Ave., Vancouver, B. C., Canada. TURNER, Edmond S. (A 1939) Pres., Wm. S. Turner & Co., 311 Pacific Bldg., and (for mail) 3455 N.' E. 36th Ave., Portland, Ore. - TURNER. George G. (A 1934) Western Repr. (for mail) Heating & Ventilating, 228 N. LaSalle St., Chicago, and 827 Hinman Ave., Evanston, III. ` TURNER, John (M 1930) Engr. (for mail) Capitol Engineering Co., Potter and Binney Sts.. Cambridge, Mass., and Contoocock, N. H. TURNER, Prescott K. (A 1937; J 1935) Engr., L. C. Kelly Sates Co., 300 Fairfield Ave., Bridge port,and (for mail) 99 GroveSt., Stratford, Conn. TURNO, W. G. W. (M 1917; A 1912) Secy., H. W. Porter & Co., Inc., Newark, and (for mail) 71 Lafayette Ave., East Orange, N. J. TUSCH, Walter (M 1917) Secy., Teeney & Ohmes, Inc., 101 Park Ave., New York, and (for mail) 881 Sterling Place, Brooklyn, N. Y. TUTHILL, Arthur F. (S 1938) Instructor Mech. Engrg. (for mail) The Cooper Union, Cooper Sq., New York, and Cutchogue, L. I., N. Y. -' TUTSCH, Rodney J. (7 1939) Asst. Mgr. (for mail) Iron Fireman of Milwaukee. Inc., 4507 W. Wisconsin Ave., and 4455 N. Oakland' Ave., Milwaukee, Wis. TUTTLE. George H.* (M 1937; A 1936; J 1934) Htg. Engr. (for mail) The Detroit Edison Co., 2000 Second Ave., and 16714 Kentfield, Detroit, Mich. TUTTLE, J. Frank (M 1913) Sales Agent (for mail) Warren Webster fit Co., 127 Federal St., Boston, and 9 Lewis Rd., Winchester, Mass. TUVE, G. L.* (M 1932) (Council, 1939) Prof, of Heat-Power Engrg. (for mail) Case School of Applied Science, Cleveland, and 2510 Newbury Dr.. Cleveland Heights, O. TUXHORN, David B. (M 1936) Engr., L. P. Steuart and Bro., Inc., 138-12th St., N. E., and (for mail) 4853 Sedgwick SL, N. W., Washing ton, D. C. TWIST, Charles F. (M 1921) Pres.. (for mail) Ashwell-Twist Co., 967 Thomas St., and 2310 Tenth Ave., N., Seattle, Wash. TWIZELL, Edwin W. (M 1937) Partner (for mail) Connolly & Twizell Regd., 1405 Bishop St., and 5176 Westbury Ave., Montreal, P. Q., Canada. TYLER, Roy D. (M 1928) (for mail) Modine Mfg. Co., 101 Park Ave., Room 1734, New York, N. Y., and 5 Ferris Drive, Old Greenwich, Conn. TYSON, William H. (if 1928) Mgr. of Engrg. (for mail) Goodyear Tyre .& Rubber Co., Ltd., and "Kipevva" Codsail Rd., Nr. Wolverhampton. England. u UHL, Edwin J. (M 1925) Partner (for mail) Uhl Co., 132 S. Tenth St., and 4830 Pleasant Ave^ S., Minneapolis, Minn. UHL, Willard F. (M 1918) Partner (for mail) Uhl Co., 132 S. Tenth St., and 4716 Lyndale Ave., S., Minneapolis, Minn. " UHLHORN, W. J. (M 1920) 733 S. Highland Ave., Oak Park, 111. ULLRICH, Anton B,, Jr. (7 1937) Sales Engr., Gilbert Engrg. Co., 1305 Liberty Bank Blag., Dallas, Tex. . .. UPSON, Walter L. (M 1938) Dir. of Research (for mail) Torrington Manufacturing Co., Tor- rington, and Litchfield, Conn. - URBAN, Frank F. (A 1939) Vice-Pres.. Urban Plumbing & Heating Co., 1215 S. W. 5th Ave^ and (for mail) 6726 S.' W. Burlingame Ave^ Portland, Ore. URDAHL, Thomas H. (M 1930) Consulting Engr. (for mail) 726 Jackson Place, N. W., and 1505 44th SL, N. W., Washington, D. C. V VALE, Henry A. L, {M 1929) Managing Director (for mail) Vale & Co., Ltd., 141-43 Armagh St., and 203 Ilam Rd., Fendalton, Christchurch, New Zealand. . VAN. ALSBURG, J, H.* \M 1931) Sales Engr., Hart & Cooley Mfg. Co., 61 W. Kinzie St., Chicago, 111. VANCE, Louis G. (M 1919) Partner, VanceMcCrea Sales Co., 2700 Sisson St., and (for mail) 4402 Maine Ave., Forest Park, Baltimore, Md. VANDERHOOF, A. L. (A 1933) Dist. Repr. (for mail) Warren Webster & Co,, 2341 Carnegie Ave., Cleveland, and 2762 Landon Rd., Shaker Heights, O. VAN NOUHUYS, Herbert C. (7 1937) Engr., Detroit Southern Pipeline Co., 9332 Buffalo Blvd., Hamtramck, and (for mail) 2007 Seward Ave., Detroit, Mich. VAN NUYS. Jay C. (7 1938; S 1936) Junior Partner. P. C. Van Nuys, Archt., 1 W. Main St., and (for mail) 56 W. Cliff St., Somerville, N. J. VARNER, John L. (A 1935) Air Cond. and Com mercial Engr., Jacksonville Refrigeration, Inc., 35 W. Monroe St., and (for mail) 26 W. 6th SL, Jacksonville, Fla. VAUGHAN, John G-, Jr. (7 1935) Asst. Engr. (for mail) U. S. Housing Authority, Tech. Div., N. Interior Bldg., Washington, D. C., and 8405 16th St., Silver Spring, Md. VAUGHAN, Lillian Lee {M 1938) Prof, of Mech. Engrg. (for mail) North Carolina State College, State College Station, and 11 Enterprise SL, Raleigh, N. C. VAUGHN, Frank R. {M 1937; A 1936) Vice-Pres. (for mail) Green Foundry & Furnace Wks., and 532 Polk Blvd., Des Moines, la. 67 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 VEALE, Tinkham (7 1938) Sales Engr.. Avery Engineering Co., 2341 Carnegie Ave., Cleveland, and (for mail) 18519 Kinsman Rd.. Shaker Heights, O. VEGLERY, Alexander (A 1939) (for mail) Ship ping Dept., Socony-Vacuum Oil Co., Inc., P. O. Box 660, and Dirhem So., No. 11, Yenikoy. Istanbul. Turkey. VELTMAN, B. M. (Af 1936) Sales Engr., Western Blower Co.. 1800 Airport Way, and (for mail) 5531 Seward Park Ave., Seattle, Wash. VERNON, J. Rexford (Af 1928; A 1926) Ad vertising Mgr. (for mail) Johnson Service Co., 1355 Washington Blvd., Chicago, and 733 Brummel St., Evanston, 111. * VERVOORT, Edward L. (7 1937; 5 1936) Sales Engr., Brooklyn Union Gas Co., 180 Remsen St., Brooklyn, and (for mail) 31 Yale Place, Rockville Centre, L. I., N. Y. VETLESEN, G. Unger (Af 1930) Consulting Engr., 1 Beekman Place, New York, N. Y. VIDALE, Richard (Af 1935) Air Cond. Engr. (for mail) Flesch & Schmidt, Inc., 118 Brown St., and 92 Harding Rd., Rochester, N. Y. VINCENT, Paul J. (Af 1931) Owner, Paul J. Vincent Co., 2208 Maryland Ave., Baltimore, Md. . VINSON. Neal L. (7 1936; 5 1932) Engr. and Estimator (for mail) L. W. Vinson & Son, Box 3007, Lowell and Bisbee, Ariz. VISSAC, Gustave A. (Af1937) Consulting Mining Engr., Coal Preparation. 1325 Frontenac Ave., Calgary. Alta., Canada. VIVARTTAS, Eugene (Life Member; M 1910) Engr., 154 Maine Ave.. West Brighton. S. I.. N. Y. VOISINET, Walter E. (Af 1930) Repr. (for mail) John J. Nesbitt, Inc., 250 Delaware Ave., Buffalo, and 151 Warren Ave., Kenmore, N. Y. VOLBERDING, Leroy A. (A 1936) Deer Lake Dr., Rte. 1, Clarkston. Mich. VOLK, Joseph H. (Af 1923) Pres, and Treas. (for mail) Thos. E, Hoye Heating Co., 1906 W. St. Paul Ave.. and 2965 South 43rd St.. Milwaukee. Wis. VOLKHARDT, Aqulla N. (M 1938) Owner (for mail) A. N. Volkhardt, 942 Bay St., and 104 Townsend Ave., Rosebank, S. I., N. Y. VOLLMANN. Carl W. (Af 1938) Pres, (for mail) Linde Canadian Refrigeration Co., Ltd., 355 St. Petre St., Montreal, and 517 Roslyn Ave., Westmount, P. Q.. Canada. vonCHRISTIERSON, Carl A. (A 1939; 7 1937) Field Engr., Carbondale Dept., J. H. Vivian & Co., P. O. Box 301, and (for mail) P. O. Box 3249 Johannesburg, South Africa, von ROSENBERG, Paul C. (7 1939) Htg. & Vtg. Engr., Illinois Engineering Co., 2035 S. Racine Ave., and (for mail) 1221 Hood Ave., Chicago, IU. VOORHEES, G. A. (M 1922) Mgr. (for mail) Furblo Co., and P. O. Box 63. Hermansville, Mich. VOSS. Walter W. (A 1938) 1347 N. Dearborn St., Chicago. 111. VROOME, Albert E. (Af 1932) Air Cond. Engr., Phoenix Engineering Corp., 2 Rector St., New York, and (for mail) 6218 Amboy Rd., Prince Bay. a I., N. Y. w WACHS, Louis J. (A 1936 : 7 1930) Salesman. Carrier Corp., Chrysler Bldg., and (for mail) 1820 Cortelyou Rd., Brooklyn, N. Y. WADDINGTON, B. C. (Af 1922) 4523 Wirt St.. Omaha, Nebr. WADE, Richard H. (M 1937) Engr., Spencer Heater Co., 101 Park Ave., New York, and (for mail) 130-72-230th St., Laurelton. L. I., N. Y. WADSWORTH, Raymond H. (7 1937) Air Cond. Sales Engr. (for mail) Clarage Fan Co., 500 Fifth Ave., New York, N. Y., and 112 Summit St., East Orange. N. J. WAECHTER, Herman P. (A 1930; 7 1927) Air Cond Engr., W. T. Grant Co., 1441 Broadway, and (for mail) 308 W. 44th St., New York, N. Y. WAGGONER. Jack H. (M 1937) Product Control Supervisor, Owens-Corning Fiberglas Corp., and (for mail) 214 Rugg Ave., Newark, O. WAGNER, Earle K. (Af 1938) Sales Erigr. (for mail) The Powers Regulator Co., 2240 N. Broad St.. Philadelphia, and 312 Myrtle Ave., Chelten ham, Pa. WAGNER, Edward A. (Af 1937; A 1936) Pres., Wagner Engineering Corp., 22 Dunham St., and (for mail) 28 Waverly St., Pittsfield. Mass. WAHRENBROCK, Orin K. (A 1939; 7 1936) Engr., Automatic Appliance Corp., 36 Richmond Hill Ave., Stamford, Conn., and (for mail) 4062- Swift St., San Diego, Calif. WAID, Glen H. (A 1930) Dist. Sales Mgr., Scott Valve Mfg. Co., 3963 McKinley Ave., and (for mail) 2928 Northwestern Ave., Detroit, Mich. WALDEN, H. Kenneth (7 1939) Secy, (for mail) Haydn Myer Co., Inc., 2224 Comer Bldg., and 512 S. W. 5th St., Birmingham, Ala. WALDON, Charles D. (A 1932) Consulting Engr... Spencer Foundry Co., Penetang, and (for mail) 32 Femdale Ave., Toronto, Ont., Canada. WALDREP, James E. (7 1939) Htg. 8: Air Cond. Engr., Poe Piping & Heating Co., Box 1940, and, (for mail) 14 Whitner St., Greenville, S. C. WALFORD, Leslie C. A. (Af 1938) Chief Designer, G. Lome Wiggs, Consulting Engineer, 727 Uni versity Tower, and (for mail) 4264 Royal Ave., Notre Dame de Grace, Montreal, P. Q., Canada. WALKER. Edmund R. (M 1934) Mgr. Htg. Div. (for mail) Fedders Mfg. Co., Inc., 57 Tonawanda St., Buffalo, and 365 McKinley Ave., Kenmore, N. Y. WALKER, J. Herbert* (M 1916) (Council, 1938 1939) Engrg. Asst, to the Gen. Mgr. (for mail) The Detroit Edison Co., 2000 Second Ave., Detroit, and 432 Arlington Rd., Birmingham, Mich. WALKER, Kirby (Af 1935) Sales Engr., Walker & Eder, 37 W. 39th St., New York. N. Y. WALLACE, David R. (A 1937) Htg. Engr. (for mail) Young & Bortic Coal Co., 9'Franklin Ave., Ridgewood, and 94 Harding Rd., Glen Rock, NJ. WALLACE, George J. (Af 1923) Principal Engr. and Contractor. 96-19-35th Ave., Corona, and (for mail) 27-36 Ericsson St.. East Elmhurst, L. I., N. Y. WALLACE, George N. (Af 1937) (for mail) George N. Wallace Co., 271 Madison Ave., New York,' and 77 Valley Rd., New Rochelle, N. Y. WALLACE, Harry P., Jr. (A 1936) Branch M$r., Sales Promotion (for mail) Crane Co., 400 Third Ave., N., and 4909-34th Ave., S., Minneapolis, Minn. WALLACE, William M., II (Af 1929) Resident Partner (for mail) Syska & Hennessy, Cons. Engrs., Ill N. Corcoran St., and 2603 Highland Ave., Durham, N. C. WALSH, Edward R., Jr. (M 1936; A 1935) Head of Automatic Htg. Div., York Ice Machinery Corp., and (for mail) Wyndham Hills, York, Pa. WALSH, James A, (A 1932: 7 1929) Vice-Pres. & Gen. Mgr. (for mail) Air Conditioning Co.. 1017 ` Sampson St., and 513 Branard St., Houston, Tex. WALTERS, Arthur L. (Af 1928; A 1925; 7 1924) Chief Engr. (for mail) Green Foundry & Furnace Works, 322 S. W. 3rd SL. and 900-29th St., Des . Moines. Ia. WALTERS, William T, (Af 1917) Engr., Illinois Engineering Co., Cor. 21st St., and Racine Ave., and (for mail) 12747-Wallace Ave.. Chicago, 111. WALTERTHUM, John J. (A 1922) Htg.-Vtg. Contractor, 212 E. 58th St.. New York, N. Y., and (for mail) 42-a Van Reipen Ave., Jersey City, N. J. WALTHER, Frederick G. (A 1939; 7 1938) Draftsman and Engr., York Ice Machinery Corp., 42nd St., Brooklyn, and (for mail) 4606 Richard son Ave., Bronx, N. Y. . ROLL OF MEMBERSHIP WALTON, Charles W., Jr. (Af 1934) Mech. Engr. (for mail) Rockefeller Center, Inc., 50 Rockefeller Plaza, New York, N. Y., and 120 Monte Vista Ave., Ridgewood, N. J. WALZ, Chester D. (A 1939) Assoc. Mech. Engr., 11th Naval Dist., San Diego, and (for mail) 709 25th St., Santa Monica, Calif. WALZ, George R. (A 1940; 7 1937) Sales Engr. (for mail) Minneapolis-Honeywell Regulator Co., 1101 Vermont Ave., N. W., Washington, D. C., and 1808 Queens Lane. Apt. 209, Arlington. Va. WARD, Edward B. (Af 1937) Pres, (for mail) Edward B. Ward & Co., 270 Fremont St., and 235 Lansdale Ave., San Francisco, CaUf. WARD, Frank J. (Af 1935) Owner (for mail) Frank J. Ward Co., 237 W. Court St., Cincinnati, O., and Cold Spring, Ky. WARD, Harry H. (A 1937) Dist. Engr., Frigidaire, Meltzer Motor Co., 230 N. E. 14th St., and (for mail) 273 N. W. 92nd St., Miami. Fla. WARD, Jerry J. (A 1921) Pres, (for mail) Wenzler & Ward, Inc., 1703 Textile Tower, and 1107 31st Ave., Seattle. Wash. WARD, Oscar G. (Af 1919) Vice-Pres. & Dist. Mgr. (for main Johnson Service.Co., 1355 Washington Blvd., Chicago, and 1345 Ashland Ave., Wil mette, 111. WARDELL, Arthur (Af 1935) Asst. Prof, of Engrg. Drawing, University of Toronto, and (for mail) 124 Melrose Ave., Toronto, Ont., Canada, WARE, John H., Ill (Af 1937) Vice-Pres., Citizens Gas & Fuel Co., Pres., Oxford Co.: Vice-Pres., Gas Oil Products, Inc. (for mail) 45 S. Third St., and "The Woods", Oxford, Pa. WARING, James M. S. (Af 1932) Consulting Engr., 277 Park Ave., New York, N. Y. WARREN. Francis C. (Af 1934) Branch Mgr., (for mail) American Blower Corp., 200 Division Ave., N., and 329 Gladstone Ave., S. E., Grand Rapids, Mich. . WARREN, John S., Jr. (7 1937) Sales Engr. (for mail) York Ice Machinery Corp., 115-121 South 11th St., and 2017 Maury Ave., St. Louis, Mo. WARREN, Robert M,, Jr. (7 1938) Chief Engr. (for mail) Page-Williamson, Inc., 228 W. First St., and 522 Fenton Place, Charlotte, N. C. WASHINGTON, Laurence W. (Af 1929) (for mail) The Powers Regulator Co., 702 American Bldg., and 1627 Northwood Drive, Cincinnati, O. WASSER, Munny (Af 1938) Htg., Vtg. & Air Cond. Engr., Vasile Lascar 8, et II, Bucharest, Roumania. WASSON, Robert A. (Af 1938) Eastern Dist. Mgr. (for mail) Clarage Fan Co., 500 Fifth Ave., New York, and 15 Willow St., Brooklyn. N. Y. WATERMAN, John H. (Af 1931) Engr. (for mail) Ch&8. T. Main, Inc., 201 Devonshire St., Boston, and 7 Centre St., Cambridge, Mass. WATERS, Frank A. (A 1936) Htg.-Vtg. Engr., Westinghouse Elec. Supply Co., 150 Varick SL, New York, and (for mail) Bedford Hills, N. Y. WATERS, George G. (Af 1931; A 1926) Dist. Mgr. (for mail) American Blower Corp., 1433 Oliver Bldg., and 110 Longuevue Drive, Pittsburgh (16), Pa. WATKINS, George B. (A 1936) Dir. of Research (for-mail) Libbey-Owen-Ford .Glass Co., 1701 E. Broadway, and 3004 Berdan Ave., Toledo, O. WATSON, Kenneth W. (A 1939) Mgr. Htg. Dept., Crane Co., 710 N. W. 14th Ave., and (for mail) 11012 N. E. Prescott Ave., Portland, Ore. WATT, Richard M.. Jr. (Af 1939) Lt. Com mander (CC) (for mail) U. S. Navy, 2121 Navy Dept., Washington, D. C., and 2328 S. Nash SL, Arlington, Va. WATT, Robert D. (7 1937) Engr.. H. W. Beecher. Consulting Engr., Securities Bldg., and Pres., Electrol Oil Burner Corp., 314 Stewart St., and (for mail) 3617-47th Ave., N. E., Seattle, Wash. WATTS, Albert E. (A 1937) Mgr., A. E. Watts, 637. Craig St., W., and (for mail) 2347 Beaconsfield Ave., N. D. G., Montreal, P. Q., Canada. WAUDBY, Walter (Af 1938) Engr. (for mail) American Radiator Co.. 149 Blvd., Haussmann, Paris, and (for mail) 26 Rue de la Tourelle, Boulogne sur Seine, France. WAUNG, Tsing Fi (Af 1935; 7 1933) Htg. Engr., (for mail) Andersen Meyer & Co., Ltd., Yuen Ming Yuen Rd., and Apt. A-5, 1562 Ave. Joffre, Shanghai, China. WAYLAND, Clarke E. (A 1937) Vice-Pres. (for mail) Western Asbestos Co., 675 Townsend St., and 42 Allston Way, San Francisco. Calif. WEATHERBY, Edward P., Jr. (7 1936; S 1935) Product Engr., Air Conditioning Dept., General Electric Co., 4966 Woodland Ave., Cleveland, and (for mail) 1243 Warren Rd., Lakewood, O. WEBB, Ernest C. (Af 1935) Engrg. Service Mgr. (for mail) Iron Fireman Mfg. Go., 3170 West 106th St., Cleveland, and 1202 Woodside Drive. Rocky River, O. WEBB, John W. (Af 1926) Managing Dir. (for mail) Webb Dust Removing & Drying Co., Ltd., Vinery Works. Town Lane, Denton Nr. Man chester, and "Ebor," Brinnington, Stockport, England. WEBER, Erwin L. (Af 1921) Consulting Engr., 534 Medical Arts Bldg., Seattle, Wash. WEBER, Eugene F. (A 1940; 7 1937) Sales Engr., York Ice Machinery Corp., 117 S. 11th St., and (for mail) 4405 W. Pine, St. Louis, Mo. WEBSTER, E. Kessler (Af 1915) Secy. & Asst. Gen. Mgr. (for mail) Warren Webster & Co., 17th and Federal Sts., Camden, and First Ave. & Kings Highway. Haddon Heights, N. J. ' WEBSTER, Warren, Jr. (Af 1932; 7 1927) Pres, and Treas. (for mail) Warren Webster & Co., 17th & Federal Sts., Camden, and 200 Colonial Ridge Drive, Haddonfield, N. J. WECHSBERG, Otto (Af 1932) Pres.-Gen. Mgr. (for mail) Coppus Engineering Corp., 344 Park Ave., and 4 Richard St., Worcester, Mass. WEDDELL, George O. (Af 1936) Branch Mgr., York Ice Machinery Corp., 2400 Parson St., and (for mail) 3114 Wainbell Ave., Dormont, Pitts burgh, Pa. ` WEGMANN, Albert (Af 1918) Owner, A. Wegmann Co., 2811-13 W. Fletcher St., and (for mail) 6206 North 17th St., Philadelphia, Pa. WEID, Harry L. (S 1938) Test Engr., Hynes Electric Heating Co., 240 Cherry St., Philadel phia, Pa., and (for mail) Blackwood, N. J. WEIL, F. H. Eugene (A 1938) Engr., The Maag Co., 831 N. Milwaukee St., and (for mail) 2515 N. 59th St., Milwaukee. Wis. WEIL, Martin (A 1925) Vice-Pres. (for mail)-' Weil-McLain Co., 641 W.'Lake St., and 4259 Hazel St., Chicago, 111. - WEIL, M. I. (A 1928) Pres, (for mail) Chicago Pump Co., 2336 Wolfram SL, and 3300 Lake Shore Drive. Chicago, 111. WEIMER, Fred G. (A 1919) Mgr.. Milwaukee Office, Kewanee Boiler Corp., 312 It. Wisconsin Ave., Room 503, and (for mail) 3958 N. Stowell Ave., Milwaukee, Wis. . WEINERT, Fred C. (A 1937) Asst. Sales Mgr., Sales Engr. (for mail) Chamberlin Metal Weather Strip Co., Inc., 1254 Labrosse St., Detroit, and Rte. No. 2, Plymouth, Mich. WEINSHANK, Theodore* (Life Member', M 1906) (Board of Governors. 1913) Consulting Engr., 3307 Belden Ave., Chicago, 111. WEISS, Arthur P. (Af 1928) Burnham Boiler Corp., Irvington, and (for mail) 134 Farrington Ave., North Tarrytown, N. Y. WEISS, Carl A. (Af 1936; A 1924) Gen. Mgr. (for mail) Kornbrodt Kornice Co., 1811-15 Troost Ave., and 29 East 68th St., Kansas City, Mo. WEISSBLATT, Norman (S 1938) Student. N. Y. Technical Inst., 108 Fifth Ave., New York, and (for mail) 1435 53rd St., Brooklyn, N. Y. WEITZEL, Cameron B. (Af 1936) Owner and Operator, 122 E. High St., Manheim, Pa. WEITZEL, Paul H. (7 1936; S 1934) Jr. Engr., Cameron B. Weitzel, 122 East High St.. Man heim, Pa. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 WELCH, Louis A., Jr. (A 1929) Owner (for mail). Welch Bros., 443-2nd St., and 2001 Campbell Ave., Schenectady, N. Y. , WELDY, Lloyd O. (Af 1930) Branch Mgr. (for WHITE, Eugene B. (Af 1934) Arch. & Engr. (for. mail) Architectural & Engineering Bureau, 19 S. LaSalle Street, Chicago, and 309 N. Taylor Ave., Oak Park, 111. - mail) The Powers Regulator Co., 2341 Carnegie WHITE, Everett A. (Af 1921) Mgr., Crane Co., Ave.. Cleveland, and 19623 Laurel Ave., Rocky 921 E. Monroe, and (for mail) 1010 W. Edwards River, O. ' St., Springfield, 111. WELLER, Albert K. (A 1939) Factory Agency WHITE, Everett G. (A 1938) Asst. Custodian (for mail) 1231 N. W. Hoyt St., and 3827 N. E. Engr., Bronx Central Post Office, Bronx, and Davis SL, Portland, Ore. (for mail) 425 Rochelle Terrace, Pelham Manor, 1 WELLS, Earl P.* (Af 1938) Air Cond. Engr., Gay N. Y. ` . Engineering Corp., 2730 E.-llth St., Los Angeles, WHITE, Harry S. (A 1936) Mgr. (for mail) Acme and (for mail) 1133 Graynpld Ave., Glendale, Sheet Metal Co., 2201 Broadway, and 20 West cam. .. . .,, Dartmouth Rd., Kansas City, Mo. . WELLS, William F.* (Af 1939) Dir. Lab. for WHITE, John C. (Af 1932) State Power Plant . Study of Air-Borne Infection (for mail) .Uni ! Engr. (for mail) Wisconsin Bureau of Engineer versity ` of Pennsylvania, School of- Medicine, ing, Power Plant Div., 624 E! Main St., and 622 Philadelphia, and 112 Pine Ridge. Media. Pa. E. Main St., Madison, Wis. WELSH, Harvey A. (A 1936) Eastern Dist. Mgr., WHITE, Taylor G., Jr. (A 1937) Branch Mgr., Control Corp. of Minneapolis (for mail) 4118 Lee U.S. Radiator Corp., 709 Ashland, Louisville, Ky. Highway. Arlington, Va. . - - ' WENDT, Edgar F. (Af 1918) Pres, (for mail) Buffalo Forge Co., 490 Broadway, and 120 Lincoln Parkway, Buffalo, N. Y. WHITE, Thomas J. (7 1938) Sales Engr. (for mail) American Blower Corp., 625 Market St., and 225 Mallorca Way, San Francisco, Calif. . WHITE, William R. (Af 1938; A 1936) Engr., Air WENDT, Edwin H. (7 1936) Engr. (for mail) O. A. Wendt Co.. 2124 N. Southport Ave., and 4728 N. Lawndale Ave., Chicago, 111. Cond. Dept, (for mail) Nebraska Power Co., 723 Electric Bldg., and 4339 Larimore Ave., Omaha, Nebr. ''' WERKER, Herwart (Af 1939) Engr.. Inst, of Thermal Research, American Radiator & Stand ard Sanitary Corp., 675 Bronx River Rd., and WHITELAW, H. Leigh (Af 1916) Jones & Laugb- lin Steel Corp., Third & Ross,. Pittsburgh. Pa., and (for mail) Rings End Rd.; Noroton, Conn. (for mail) 60 Ball Ave.,-Yonkers, N. Y. WHITELEY, Stockett M. (Af 1933) Consulting WERNER, John G. (Af 1937). Sales Engr., L. J. Mueller Furnace Co.. Lafayette & Dickson Sts., Baltimore, 'Md., and (for mail) 4512-49th St., N. W., Washington, D. C. Engr. (for mail) Baltimore Life Bldg., and 3931 Canterbury Rd.i Baltimore, Md. ' WHITMER, Robert P. (Af 1935) Secy, (for mail) . American Foundry & Furnace Co., McClun & WERNER, P. H. (7 1939) Br. Sales Mgr. (for mail) - Washington Sts... and 1402 E. Washington St., BarberrColman Co., 914 N. Broadway, and 711 Bloomington, 111. ' N. 16th St., Milwaukee, Wis. WHITNEY, C. W. (Af 1935) Pres., ABC OU WERNER. Richard K. (Af 1936) Consulting Burner & Engineering Co., 2012-14 Chestnut Engr. (for mail) 316 W. T. Waggoner Bldg., and ' St., Philadelphia; and (for mail) Apt. F-3, Sevilla 3671 Monticello Drive, Fort Worth, Tex. Court. Bala-Cynwyd, Pa. ' WESLEY, Ray O. (A 1937) Sales Engr. (for mail) WHITT, Sidney A. (A 1938; 7 1937) Htg. Div. U. S. Radiator Corp., 334 Boren. Ave., N., Engr., Fedders Mfg. Co., 57 Tonawanda St., and Seattle, and Yarrow Point. Bellevue, Wash. (for mail) 227 Linden Ave., Buffalo', N.-Y. WEST, Perry* (Af 1911) Prof, of Steam & Power WHITTAKER, Wayne K. (A 1935) Building- Engrg., Head of Dept. Mech. Engrg. (for mail) Maintenance Dept., Irving Trust/ Co., Bldg., College of Engineering. University of Kentucky, 1 Wall St., New York, and (for mail) 119-23 and 185 E. Maxwell St., Lexington, Ky. 226th St., St. Albans. L. I.. N. Y. WESTENDARP, Francisco G. (Af 1939) Chief WHITTEN, Horace E. (Af 1924) Pres, and Treas., Engr., Carrier Dept, (for mail) Guinard Freres, H. E. Whitten Co., 9 Federal Court, Boston, and Sues Dept. Tecnico, Apartado 668, Caracas, (for mail) 56 Highland Rd., Somerville, Mass. . Venezuela. WHITTINGTON, James A. (Af 1936) Utilization WESTOVER, Wendell (Af 1936) Pres, (for mail) Testing Engr. (for mail) Peoples Gas Light & Westover-Wolfe. Inc., 170 Washington Ave., and Coke Co., 3921 S. Wabash Ave., Chicago, and 143 Washington Ave., Albany, N. Y. 622 Sheridan Square, Evanston, 111. WESTPHAL, Norman E. (7 1940; 5 1937) Engr.,. WIDDOWFIELD. Arthur S: (7 1937) Sales Engr. Northern Indiana Public Service Co., and (for (for mail) The Mercoid Corp.. 4201 Belmont mail) Long Beach, Michigan City, Ind. , Ave., and 6109 N. Campbell Ave., Chicago, 111. WETHERED, Woodworth (Af 1937) Mech. Engr., WIDMER, Walter J. (A 1939) Secy.-Treas. (for Bohemian Club, Post and Taylor Sts., San mail) Widmer Plumbing & Heating Co., Inc., Francisco, Calif. ' 34 N. E. 7th Ave., and 1565 N. Shaver St., WETZELL, Horace E. (Af 1934) Chief Engr. (for mail) The Smith & Oby Co.. 6107 Carnegie Ave^ Cleveland, and 21144 Aberdeen Rd., Rocky River, O. * WHEELER, Joe, Jr. (Af 1937) Sales Repr. (for mail) Johnson Service Co., 28 E. 29th St., New York, and 261 Dogwood Lane, Manhasset, L. I., N. Y. . WHELAN, William J. (Af 1923) Purchasing and Estimating (for mail) Harrigan & Reid Co., 1365 Bagley, and 3790 Seminole Ave., Detroit, Mich. Portland, Ore. ' . WIEGNER, Henry B. (Af 1919) Branch Mgr.,- Johnson Service Co., 20 Winchester St., Boston, and (for mail) 143 Standish Rd.,. Watertown, Mass. . WIESNER, Blaine K. (5 1939) Student, Purdue University (for mail) 931 Sixth St., West Lafay ette, lnd. . WIGGS, G. Lome (Af 1936: A 1932; 7 1924) (Council, 1938-1939) Consulting Engr. (for mail) 727 University Tower and 4797 Grosvenor Ave., Montreal, P. Q., Canada. WILCOX, Chester M. (A 1939) Engr., Construes WHELLER, Harry S. (Af 1916) Vice-Pres., L. J. tion Div., Design Section, O. Q. M. G., War Wing Mfg. Co., 154 W. 14th St., New York, N.Y., Dept., and (for mail) 3118-Mt. Pleasant' St., and (for mail) 725 Union Ave., Elizabeth, N. J. N. W., Washington, D. C. WHITE, Elmer D. (A 1939; 7 1937) Draftsman WILDE, Ray S. M. (Af 1916) Consulting Mech. (for mail) A. M. Kinney, Inc., 1820 Carew Tower, Engr., 3500 Union Guardian Bldg., and (for mail) and 2201 Reading Rd., Cincinnati. O. . 194 Connecticut Ave., Highland Park, Mich. WHITE, Elwood S. (Af 1921) Pres, (for mail) U. S. Radiator Corp., 1056 National Bank Bldg., Detroit, Mich, and Meadowbank Rd., Old WILDER, Edward L. (Af 1915) Engr., Industrial Dept, (for mail) Rochester Gas & Electric Corp., 89 East Ave., and 369 Bonnie Brae Ave., Roches Greenwich, Conn. ter, N. Y. ' . . 70 ROLL OF MEMBERSHIP WILDER, Herbert P. (Af 1938) Engr. (for mail) Patterson-Kelley Co., 101 Park Ave., New York, ' and Ardsley Rd., Scarsdale. N. Y. .' WILDMAN, Eugene L. (7 1939) Mgr. Air Cond. Dept.. Stewart A. Jellett Co.. 1200 Locust St., Philadelphia; Pa., and (for mail) 132 N. Arlington Ave., East Orange, N. J. " WILEY; Donald C. (A. 1939; 7 1936) Engr. (for mail) John J. Nesbitt, Inc., State Road & Rhawn St., and Kelvin Ave., Somerton, Philadelphia, Pa. WILHELM, Joseph-E. (7 1936 ; 5 1934) Office Engr. and Purch. Agent., Avery Engineering Co., 2341 Carnegie Ave., Cleveland, and (for mail) 294 E. 195th St/. Euclid, O. . WILKES, Gordon B.* (Af 1937) Prof, of Heat Engrg. (for- mail) Massachusetts Institute of Technology, Cambridge, and 51 Everett St,, Newton Centre, Mass. .' WILKINSON,- Arthur (A 1936) Mgr.- (for mail) Wilkinson Engineering Agencies, 1253- McGill College Ave., Montreal, and 469 Argyle Ave., Westmount. P. Q.. Canada. WILKINSON, F. J. (Af 1933) Mgr., Cent. Engrg. Service, Montgomery Ward & Co.-, Chicago Ave. & Larabee St., Chicago,' and (for mail) 18257 . Martin Ave., Homewood, 111. ' WILLARD, Arthur C.* (Af 1914) {Presidential Member) (Pres., 1928; 1st Vice-Pres., 1927; 2nd Vice-Pres.. 1926; Council, 1925-1929) (for mail) President, University of Illinois, and 711 Florida Ave.. Urbana, 111. . WILLER, Murray D. (7 1937; 5 1936) Air Cond. Engr., F. W. Chambers & Co.-, Ltd., 96 Bloor St., W., arid (for mail) 1243 St. Clair Ave., W., Toronto, Ont., Canada. WILLEY, Earl C. (Af 1934) Asst. Prof, of Mech. Engrg., Oregon State College, and (for mail) ' 121 N. 29th, Corvallis, Ore. WILLIAMS, Allan E. (Af 1938) Branch Mgr. (for . mail) Buffalo Forge Co., 428 Dwight Bldg.', and ' 3535 Wabash Ave., Kansas City, Mo. ` WILLIAMS, Allen W. (Life Member; A 1915) Managing Dir., National Warm Air. Heating & ' Air Conditioning Association, 5 E. Long St., Columbus, O. WILLIAMS, Chester D. (Af 1938) Mgr.,-General Air Conditioning & Heating Co. (for mail) 4001 Piedmont Ave., Oakland, and 2709 College Ave., Berkeley, Calif. . WILLIAMS, Donald D. (A 1940 ; 7 1937) Gas Htg. Engr.' (or .mail) lowa-Nebraska Light & - Power Co., 14th and O Sts., and 2236 A St., Lincoln, Nebr. WILLIAMS, Douglas C. (A 1938) 595 Illinois "Rd., Lake Forest, I1L ' WILLIAMS, Elwin C. (A 1939) Sales Engr. & Repr. (for mail) 4028 Egbert Ave., Cincinnati, O. WILLIAMS, Frank H. (A 1940; 7 1934) Engr., Frigidaire Div., General Motors Sales Corp., 4584 Maybury Grand Ave., Detroit, and (tor mail) 68 Amherst Rd., Pleasant Ridge, Mich. WILLIAMS. Gordon S. (7 1937; 5 1936) 15 .Chapel St., Woodmont, Conn. .. ' . WILLIAMS, H. Edmund (7 1939) Jr. Engr., Nash-Kelvinator Corp., 27th St. & Pearson Place, Long Island City, and (for mail) 14 W. 103rd St., - New York, N. Y. . .* WILLIAMS, J. Walter (Af 1915) Pres, (for mail) Forest City Plumbing Co., 332 E. State St., and 923 E. State St., Ithaca, N. Y. . WILLIAMS, Lyle G. (Af 1939) Design Engr., Williams' Plumbing Co., and (for mail) P. O. Box 304, Gladstone, Ore. WILLIS, Leonard L. (7 1936; S 1935) Chief Engr., Conrad Refrigeration Co., 17 E. Hennepin Ave., and (for mail) 5036 Lyndale S., Minne apolis, Minn. : WILLNER, Ira (Af 1937) Pres, (for mail) Willner Heating Co., Inc., 415 Lexington Ave^, and 308 E. 79th St., New Yoxk, N. Y. WILLS,- Fred W. (7 1938)-Sales (for mail) Tuttle ' & Bailey, Incl, 61 W. Kinzie St., and 2511 Leland Ave., Chicago, III. WILMOT, Charles S. (Af 1919) Supervising Engr., Philadelphia, Pa;, Wilmington', Del. and Collings- wood, N. J.. Building Insulation Co., and (for mail) 406 Essex Ave., Narberth.'Pa. ' . ' ' WILSON, Alexander (Af 1936) Consulting Engr. (for mail) 1537 St. Matthew St., Montreal, P. Q., Canada. : . V.- WILSON, Alexander M. (5 1939) Engr., Andrew Wilson Co..' 616 Essex St.. Lawrence, and (for mail) 27 WillianrSL, Andover, Mass. , . WILSON, Andrew (Af 1935) Survey and Esti mating Engr., Paragon Oil Burner Corp., 75 Bridgewater St., and (for mail) 5523 Seventh Ave., Brooklyn, N. Y. . WILSON, Eric D. (Af 1936) General Mgr. in India (for mail). c/o Carrier Engrg.-Co... Ltd., 24 Buckingham Gate; .London, S. W. 1, and Tyrgorof, Ystradgynlais, Swansea, England. WILSON, Frederick-J. (A 1938) Pres, (for mail) F. J. Wilson Co.-, 1530 Chestnut Stl, Philadelphia, and 527 Baird Rd'.', Merion, Pa/' - WILSON, George. T; (Af 1925) Sales Engr., Gurney Foundry Co., Ltd., ,4 Junction- Rd., Toronto, and (for mail) 25 Tyre Ave., Islington, Ont., Canada. ' WILSON; Raymond W. (Af 1934) Member of . Firm (for mail) Wilson-Brinker Co., 412 Pythian Bldg., and 429 Creston-Aye.,-Kalamazoo. Mich. WILSON; Robert A. (Af 1936) Sales Engr., Minne- apolis-Honeywell Regulator Co., 4501 Prospect Ave., Cleveland, and (for mail) Cor. Olive St. & Rubens Court, Chagrin Falls. O. - WILSON, Victor H. (A. 1938) Distributor & Contractor in - Refractories, Plibrico -Jointless Firebrick Co., 211-8th Ave.,'N.. Nashville, and (for mail) "The Thistlepatch," Donelson, Term. WILSON, Westray E.:(A 1939) Owner' (for mail) Wilson Plumbing Co., 227 Haywood Rd;, and U0 Salola St.. Ashville, N.'C. - WILSON, W. H. (A 1932) Chief Power Plant Engr., Pullman-Standard Car Mfg. Co.. 11001 Cottage Grove AveJ, and (for mail) 22 West 110th Place, Chicago, 111. ' WILTBERGER, Constant F. (Af. 1935) Partner, Pennell & Wiltberger, Cons. Engrs., Land Title Bldg., and (for mail) 2650 North 9th St., Phila delphia, Pa. - WINANS, Glen D. (Af 1929) Engr. of Steam Distribution (for mail) The Detroit Edison Co., 2000 Second Ave., and 16183 Wisconsin, Detroit, r Mich. ' ' WINKLER, Ralph A. (A 1940; 7 1937) Sales Engr., Alfred C. Goethel Co., 2337 North 31st St., Milwaukee, and (for. mail)' P. O. Box 179, Elm Grove, Wis. '. WINSLOW, C.-E. A.* (Af 1932) Prof, of Public Health (for mail) Yale School of Medicine^ 310 Cedar St-., and.314 Prospect St., New Haven, Conn. . . . . WINSTEL, Frank E. (A 1938) Delco Sales Mgr., ; The Bimel Co.,'305 Walnut St., and (for mail) 1126 Regent Ave., Cincinnati, O. WINTERBOTTOM, Ralph F. (Af 1923) Engr., .Winterbottom Supply Co., and (for mall) 400 . Campbell Ave., Waterloo, la. . WINTERER, Frank C. (Af 1920) Sales Mgr. (for . mail) Cochran-Sargent Branch, American Radi ator & Standard Sanitary Corp., 300 Broadway, and 836 Juno St., St. Paul, Minn. - WINTHER, Anker (Af 1937; A 1936; 7 1932) (for mail) York Ice Machinery Corp., 659 E. 6th St., and 3526 Pape.Ave., Cincinnati. O. . . WISSING, Clement B. (A 1936) Secy, and Sales Mgr. (for mail) Ebner Ice & Cold Storage Co., Locust 8c Chestnut St., and 702 N. 6th St., Vindnnes, Ind. WITHERIDGE, David E. (7 1936) Sales Engr., W. A. Witheridge Co., 746 S. -Fourth Ave., Saginaw, Mich. WITMER, Charles N. (A 1937; 7 1930) Sales Engr. (for mail) Straus-Frank Co., 1618 Fannin St., and 2301 Southgate Blvd., Houston, Tex. 71 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 WITMER, Howard S. (A 1937) Design Engr., City Engrg. Office, City Hall,-and (for mail) WOOTAN, Charles (A 1937) 11118 Clifton Blvd., Cleveland, O. P. O. Box 135, Bay City, Mich. WORLD, Harry P. (M 1936) Engr., Mackenzie WITTIG, Frederick E. (7 1939) Jowein. Inc., Waters, ArchL, 96 Bloor St., W., and (for mail) 150-17 Liberty Ave., Jamaica, and (for mail) Box 30 Rosewell Ave., Toronto, Ont., Canada. . 145 Glenwood Landing, L. I., N. Y. WORMLEY, Robert F. (A 1938) Branch Mgr. WOESE, Carl F. (if 1934) Consulting Engr. (for (for mail) Grinnell Co. of Canada, Ltd., 700 mail) Robson & Woese, Inc., 1001 Burnet Ave., Beaumont St., and 6092 Terrebonne Ave., and 256 Robineau Rd., Syracuse, N. Y. Montreal, P. Q., Canada. WOLF, Philip (if 1935) Proprietor, City Con WORSHAM, Herman (if 1925:7 1918) National tracting Co., 304 East 62nd St., New York, N. Y. Business Dept, (for mail) Frigidaire Div., General WOLFF, Peter P. (if 1935) Engr., Bell & Gossett Co., 3000 Wallace SL, and (for mail) 7509 S. Ridgelan Ave., Chicago, 111. Motors Sales Corp., 300 Taylor St., and 519 W. Norman Ave., Dayton, O. WORTHING. Stanley L. (if 1936) Mech. Engr. WOLIN, Milton W. (7 1938; 5 1937) Engr., Typhoon Air Cond. Co., Inc., 252 W. 26th'SL., New York, N. Y.. and (for mail) R. F. D. (for mail) Knecht, McCarty, Thebaud, Archts., 200 Watson Bldg., Grand Rapids, and Spring Lake, Mich. No. 2, Box 73-D, New Brunswick, N. J. WORTHINGTON, Thomas H. (if 1937) Mgr. WOLL, Willard M. (if 1938) Engr. (for mail) Commonwealth Edison Co., Room 1000 Edison Bldg., and 9320 S. Throop St., Chicago, 111. (for mail) Dominion Radiator & Boiler Co., Ltd.. 405 Beaubien SL, W., and 5145 Cote SL Luc Rd., Montreal, P. Q., Canada. WOLLENBERGER. Louis (if 1938) Industrial Gas Engr. (for mail) Coast Counties Gas & Electric Co., 22 Pacific Ave., and 424 King St., Santa Cruz, Calif. WONG, W. S. B. (if 1938) Dir. (for mail) Ameri can Engineering Corp. (China) 989 Bubbling / Well Rd.. and 669 .Hart Rd., Shanghai, China. WONSON, Arthur S., Jr. (5 1938) Gauge Pro duction Foreman, John D'Arcey, Inc., 184 Parkway, Chelsea, and (for mail) Walnut Park Ave., Essex, Mass. WOOD, Alfred W. (7 1938) Sales Engr., Clare Bros. & Coy, Ltd., and (for mail) Fourth Ave., Preston, Ont., Canada. WOOD, Charles F. (if 1937) Air Cond. Mgr., Prod. Development & Application Dept., Frigidaire Div., General Motors Sales Corp., 300 Taylor St., and (for mail) 359 Aberdeen Ave., Dayton, O. WOOD, Roderick A. (7 1937) Assoc. Editor.. Shipping Management, Inc.. 425 Fourth Ave., New York, and (for. mail) 482 Bard Ave., West New Brighton, S. 1., N. Y. WOODBURY, Clyde D. (if 1938) Mech. Engr.. Iceland & Haley. Consulting Engrs., 58 Sutter St., and (for mail) 1321 37th Ave., San Francisco, Calif. WOODGER, Herbert W. (if 1939) Htg. & Vtg. Engr. (for mail) General Electric Co., 100 Wood- lawn Ave., Pittsfield, and East SL, Lenox, Mass. WOODHOUSE, Graham D. (A 1938) General Supt., Dowagiac Steel Furnace Co., and (for mail) 304 West St.. Dowagiac, Mich. - WOODMAN, Lawrence E. (if 1934) Pres, (for mail) Woodman Engineering Corp., Air Cond. Engrs., 203 E. Capitol, and 725 Adams, Jefferson City, Mo. ` WORTON, William (if 1937) Branch Mgr. (for mail) C. A. Dunham Co., Ltd., 504 Scott Bldg., and 292 Landowne Ave., Winnipeg, Man.. Canada. WRIGHT, Clarence E. (A 1940; 7 1935; S 1933) . Mgr., Htg. & Vtg. Dept., Fairmont Wail Plaster A Co., Tenth SL, and (for mail) 908 Gaston Ave., Fairmont, W. Va. WRIGHT, Daniel K,, Jr.* (7 1938) Instructor in Mech. Engrg., Case School of Applied Science, and (for mail) 2044 Cornell Rd., Cleveland, O. WRIGHT, Harris H, (if 1917) Prop, (for mail) H. H. Wright. 1322 Walnut SL, and 808 Green way Terrace, Kansas City, Mo. WRIGHT, R. A. (if 1921) Branch Mgr. (for mail) Johnson Service Co., 1113 Race St., Cincinnati, O.. and. 113 Orchard Rd., Fort Mitchell, Ky. WRIGHTSON, Wllbor T. (if 1937) Eastern Mgr. (for mail) Garden City Fan Co., 55 West 42nd SL, New York, and 22 Sagamore Rd., Bronxville, N. Y. . WUNDERLICH, Milton S.* (if 1925) Asst. Resident Mgr., Insulite Co., 1100 Builders Exchange. Minneapolis, and (for mail) 545 Ml Curve Blvd., SL Paul, Minn. WYATT. DeWltt H. (if 1936) Consulting Engr. (for mail) Cooling & Heating Supply Co.. 364 N. High St., and 226 Northridge Rd.. Columbus, O. WYLD, Reginald G. (if 1937) Vice-Pres.. Charge of Engineering (for mail) Chrysler Corp., Air- temp Div., 1119 Leo SL, and 736 Devonshire Rd., Dayton, O. WYLIE, Howard M. (if 1925; 7 1917) Vice-Pres. in Charge of Sales (for mail) The Nash Engi neering Co., and 51 Elmwood Ave., South Norwalk. Conn. WOODS, Baldwin M. (if 1937) Prof, of Mech. Engrg. (for mail) University of California, and 249 The Uplands^ Berkeley, Calif. Y WOODS, Edward H. (if 1934) Engr. (for mail) Higgins & Zabriskie, 314 E. State SL, and Hook YAGER, John J. (if 1921) Pres. & Treas., Place. Ithaca, N. Y. ` Goergen-Mackwirth Co., Inc!, 817 Sycamore SL. WOODWARD, Rothwell (if 1938) Air Cond. Engr., Frigidaire Div., General Motors Sales Corp., 300 Taylor St., and (for mail) 910 Cum berland Ave., Dayton, O. WOOLCOCK, Edwin (A 1938) Plbg. & Htg. Contractor (for mail) Woolcock Plumbing &' Heating Co.. 2217-15th St., and Red Coach and (for mail) 425 Woodbridge Ave., Buffalo. N. Y. YAGLOU, C. P.*(Af 1923) Assoc. Prof., Industrial Hygiene (for mail) Harvard School of Public Health, 55 Shattuck St., Boston, and 10 Vernon Rd., Belmont, Mass. YARBOROUGH, Thomas R. (if 1938) Dist. Inn, Niagara Falls, N. Y. WOOLLARD, Mason S. (M 1934) Htg. Engr., H. H. Angus, Consulting Engr., 1221 Bay St., . and (for mail) 31 Hillcrest Park Ave., Toronto, 5. Ont., Canada. . WOOLLEY, J. Herbert (A 1936) Vice-Pres. (for mail) Woolley Coal Co., Inc., 12 Burnett Ave., Maplewood, and Oakview Terrace, Short Hills, Sales Engr., Frigidaire Div., General Motors Sales Corp., and (for mail) 788 Greenwood Ave., Apt. 4, Atlanta, Ga. YATES, James E. (if 1934) Mgr. (for mail) Yates. Neale & Co.. 231-10th SL, and 431-16th St.. Brandon, Man., Canada. ' YATES, James E., Jr. (7 1936) Sales Engr. (for ' mail) Yates, Neale & Co., 231-10th SL, and N. J. 43l-16th St., Brandon, Man., Canada. WOOLSTON, A. H. (if 1919) Chief Engr. (for YATES, Joseph E. (if 1939) Asst. Engr. (for mail) mail) Woolston-Wooas Co., 2132 Cherry St., and - Pacific Power & Light Co..,405 Public Service 4815 N. 12th St.. Philadelphia. Pa. Bldg., and 1820 N. E. 57th Ave., Portland, Ore. 72 ROLL OF MEMBERSHIP YATES, Robert A. (7 1939) Steamfitter (for mail) Yates, Neale & Co.. 231-10th St., and 431-l6th SL, Brandon, Man., Canada. YATES, Walter (Life Member; if 1902) Governing Dir. (for mail) Matthews & Yates, Ltd., Cyclone Worlra, Swinton, Manchester, and 4 Egerton Park, Worsley, Manchester, England. YEAZEL, Gordon A. (7 1938) Air. Cond. Engr., Sampson Electric Co., 3201 S. Michigan Ave., and (for mail) 8130 EberharL Chicago, 111. YERRES, WUllam L. (A 1937) Engr. (for mail) c/o Miss P. McCochrane. 103 Washington Ave.. Albany, N. Y. YOUNG, Emil O. (A 1935) Pres, (for mail) Young Regulator Co., 4500 Euclid Ave., and 2040 East 83rd St., Cleveland, O. YOUNG, Forest H,, Jr. (A 1936) Mgr.. Secy.Treaa., Young Heat Engineering Co., 116 N. 26th St., Billings, Mont. YOUNG, Harold J. (if 1937) Sales Engr.. Young Radiator Co., Occidental Hotel Bldg., and (for mail) 1364 Lakeshore Drive, Muskegon, Mich. YOUNG, J. T,, Jr. (A 1936) Mgr., Htg. Dept, (for mail) Crane Co., Box-1410, and 1364 Ken sington Ave., Salt Lake City, Utah. YUSKA!; Leonard J. (5 1938) 41-C Quadrangle, Iowa City. Ia. Z ZACK, Hans J. (if 1928) Pres., Zack Co., 2311 Van Buren SL, Chicago, 111. ZANGRILLI, Albert J. (7 1937; 5 1935) Htg. Engr., Zangrille Plumbing Co., 7930 Frankstown Ave., and (for mail) 230 Hastings St., Pittsburgh, Pa. ZEMELMAN, Irving M. (S 1939) Asst. Engr., Sears, Roebuck & Co., Port Newark, and (for mail) 85 Schuyler Ave., Newark, N. J. ZIBOLD, Carl E. (if 1929) Mech. Engr.. Htg. and Vtg., 13 Chadwick Rd., Westminster Ridge, White Plains, N. Y. ZIEBER, W. E. (if 1935) Asst. Chief Engr. (for mail) York Ice Machinery Corp., Roosevelt Ave., and 112 S. Penn SL, York, Pa. ZIESSE, Karl L. (A 1931) Secy.-Treas. (for mail) Phoenix Sprinkler & Heating Co., 115 Campau Ave., N. W., aiid 315 Hampton Ave:. S. E., Grand Rapids, Mich. ZIMMERMAN, Alexander H. (if 1939; A 1930) Ventilation Engr., Chicago Board of Health, 54 W. Hubbard SL, and (for mail) 6259 N. Francisco Ave., Chicago, III. ZINK, David D. (if 1931) Engr. in Charge of Air Cond. Div. (for mail) B. D. R. Engineering Corp., Midland Bldg., Kansas City, and Hickman Mills, Mo.. ZITZMAN, Francis T. (7 1940; 5 1938) Asst. Master Mechanic, South Mills, Jones & Laughlin Steel Corp., Aliquippa, and (for mail) 411 Pine St., Beaver Falls, Pa. ZOKELT, C. G. (if 1921) Consulting Engr.. 3810-24th Ave., S., Seattle, Wash, ZOLITSCH, Harry G. (A 1938) Partner (for mail) George J. Zolitsch & Son, 123 Grape St., and 392 Sandera Rd., Buffalo, N. Y. ZUBER, Otto (A 1938) Chief Engr. (for mail) Amana Society, Refrig. Dept., Amana, and South Amana. la. ZUHLRE, W. R. (if 1928) 54 Midland Ave., Yonkers, N. Y. ZUMWALT, Ross (7 1938) Partner (for mail) Zumwalt & Vinther, 507 Thomas Bldg., and 4501 Sycamore SL, Dallas, Tex. ZUROW, William (7 1937) Sales Engr. (for mail) St. Joseph Railway, Light, Heat & Power Co., 520 Francis St., and 728 South 10th St., St. Joseph, Mo. . ZWALLY, August L. (A 1937) Chief Air Cond. Engr.. Interstate Electric Co., and (for mail) 908 Elmwood, Shreveport, La. * 73 SUMMARY OF MEMBERSHIP .. . ...... -. .. :2 Presidential Members .- ' ! - 23 A3 ........................ .......... 1676 Total. ...... ... 937 . 39t ______55 ................ ..................... ......... ......... 3147 UNITED STATES AND POSSESSIONS Alabama... Alaska...... ; Arizona..... Arkansas... California. Canal Zone (Panama). Colorado.....-................. . Connecticut------ -----Delaware......^------- .-. District of Golumbla.- Florida__............. Georgia................. J..-.:..: Illinois..........................-- Indiana........................... Iowa....... _........................ Kansas...................-......... Kentucky....................... Louisiana........ ............... Maine.... .......................... Maryland........................ Massachusetts.--......... Michigan...... .................. Minnesota...................... Mississippi..................... Missouri........... .............. Montana......................... Nebraska.-...................... New Hampshire........... New Jersey..... _............. New York....... --............. North Carolina:........ -- Ohio................................. Oklahoma.-.................... Oregon ;.................... Pennsylvania-............... Philippine Island------- Rhode Island--............. South Carolina............. South Dakota............... Tennessee....................... Texas................................ Utah................................. Vermont......................... Virginia........................... .... 11 1 .... 5 ... 3 115 .1 12 .. 35 ..... 14 ; 76 ... 13 ... 39 .... 277 .... 33 ..... 38 .... 18 .... 15 .... 11 .... 5 .... 41 ..... 107 .... 194 ...... 109 .... 2 ...... 128 .4 ...... 38 .. 1 ...... 110 . 441 .... 31 ... 188 ...... 28 .... 44 ...... 298 ...... 2 ...... 11 .... 7 ....... 2 14 ...... 91 ...... 2 ...... 3 ...... 28 Washington.:._................... :............-- 36 West Virginia..........................9 Wisconsin............................ '................. 91 2782 DOMINION OF CANADA.____ __ 216 FOREIGN COUNTRIES Australia.......................... .12 Belgium__ -.......... 1 Bermuda.-.--....... .. 1 Brazil.................... 4 Chile.-...................................................... 1 China..................................................-- 13 Cuba... ................ 2 Denmark--................... 2 Egypt............................i.........-................ 4 England......... ........... 38 France................ -... --.......-- 9 French Indo CKihar.- .......................; 1 French North Africa...............--........ 1 Germany.-.......... ............ 4 India.... .................................................... 5 Ireland--............................ 2 Italy.............................. 7 Japan....................................................... 4 Manchukuo.................. 1 Mexico..................................................... 3 Netherland West Indies-................. 1 Netherlands................... -- .................. 3 New Zealand......................................... 4 Norway.................................................... 2 Palestine................................................. 1. Roumania.................. 1 South Africa..................................-...... 8 Spain.............................................. 1 Straits Settlements.-...................... 2 Sweden...... .............................................. 7 Turkey............................................... 2 Venezuela.............:................................. 2 149 TOTAL MEMBERSHIP.................... 3147 74 LIST OF MEMBERS (Geographically Arranged) ALABAMA Birmingham-- Cone, W. E. Drum. L. J,, Jr. Gause, H. C. Hardy, F. L. Lichty, C. P. ' Murphree. R. L. Richards, G. H. Trawick, J. G. Walden, H. K. Mobile-- Kistler, M. L. Montgomery?--- Dowdy; R. B. ALASKA Fairbanks-- Menden, P. J. ARIZONA Bisbee--: Vinson, N7 L.- V. !. 7 Glendale-^ . .. , Gabbard, F. W. , Phoenix--7., ` . . Genrei E/J. Hummel. G.W.* Tucson--.' . . Tidmarsh, P. ;M.. ARKANSAS' . Little Rock-- . ;./ Cumnock, H.' Kellogg, W. T. " McCoy, C. El - CALIFORNIA Albany-- =; Kaiip, E. O. UNITED STATES and POSESSIONS Bakersfield-- Baker, H. S. Berkeley-- Bentley, C. E. Brokaw, G. K. Emanuels, M. Harrison, G. G. Hutchinson, F. W. Peterson, C. L. Raber, B. F. Woods, B. M. Beverly Hills-- Ekings, R. M. .Jr, Theobald, A. Burlingame-- Gee, W. W. Hill, J. A. Culver City-- Owen, J. D. Fresno^-- Newman. H. E. Fullerton-- Miles, C. N. Glendale-- . Eggleston, H. L. Wells. E. P. Lockhart, C. W. McKenzie, M. C.. Jr. Miller, G. Moriarty, J. M. Nelson, E. L. Ness, W. H. C. Ott, O- W. Park. J. F. Phillips, R. E, ' Phillips, R. H. Scofield, P. C. Stanley, R. L. Steiner, T. J. . Stewart, W.'O. * Storms, R. M.'- Monterey Park-- Griffith, J. B. Oakland-- . Cummings, G. J. Passur, N. A. '; Rosen, E. J; : . Williams, C. D. HiU, E.. Jr. Holland, R. B.' Hook, F. W. Hudson, R. A. Kindorf, H. L. Kolb. F. W. v- .. Kooistra, J. F. Krueger.-J. I.- ` Leland, W. E. Marshall, T. A. Martin, Molfino, P. . Parker* R. A.'.' : Peterson, N. H. Reed, V. C. Scott, W. P,, Jr. Simons, E. W. Simonson* G. M. Ward, E. B. Wayland, C. E. : Wethered, W. White, T. J. Woodbury, C. D. ' San Jose-- Knudsen, W. R. Pacific Palisades-- Finney, B.. " Palo Alto-- ( Santa Cruz-- Carpenter, R, D. Wollenberger, -L. Johnson, O. W. Pasadena-^-;- ' Gifford, R. L." -Santa Monica-- Coghlan, S. F. Walz, C. D. . Los Angeles-- Anderson. C. S., ., Billingsley, O. F'.. II Blumenthal, Mv l. Bullock, H. H.; i Burr, K.; ; : Cline, E: A; Douglas, H; H. . Dowries, A-'H; Ellingwood; E.` L. ` English, H. Fabling, W. D. Hall, R. A. Hazlehurst. H. D. Hendrickson, H. M. Hess, A. J. Hill, F. M. - Hilleger, M. L; . Hogue, .W. M. , Hungerford, L, ': Kendall, E. H. -. Kennedy, M: 7.! Kilpatrick, W. S.' Lauer, H. B. _ Lehmann, M. Leilich, R. K. ; Piedmont-- Gayner, J. Sacramento-- Ames, C. Sr. Freeman, J. C. Kindorf, O. Porter/N. E: ' Towle, P: H. . : : San Diego-- Sadler, C. B. Wahrenbrock, O. K. San Francisco-- Bouey, A. J. Cochran, L. H. Cockins, W. W.Cooley, E. C. Corrao, J. Feyge, H. Folsom', R. A. Haley, H. S. j Hickman, H. V.' Sauaallto-- .,7.;.. Howe, W. Wv. COLORADO . Colorado Springs__ Jardine, D. C, Denver-- .. .. ' Adams, F. L. . Bowen, J. C. Brierly, K. Conrad, R. " Davis, A. F. McNevin, J. E. McQuaid, -D. " O-Rear, L. R., .. .. Pierce/E. DV. 7 \ Skelley. J. H; " La Junta-- ' : : v Curtice, J. M. ' 75 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 CONNECTICUT Bridgeport-- Earie. F. E. Smak, J. R. Fairfield-- ' Osborn. W. J. Farmington-- Andrcsen, G. C. Greenwich-- Jones, A. L. Hartford-- ` Ahlff, A. A. Peterson, H. P. New Britain-- Hart, S. Hart. T. S. New Haven'-- Rodee, E. J.. . Seeley. L. E. Teasdale, L. A. Winslow, C.-E. A. New London-- Chapin, C. G. Forsberg, W. Hopson. W. T. Noroton-- Whitelaw, H. L. Northford-- Carrier, E. G. South Norwalk-- Adams, H. E. iennings, 1. C. .yons, C. J. Mead. E. A. Wylie, H. M. Stamford--- Bowles, Pi Hoyt, L. W. Jehle, F. Jessup. B. H. Opperman, E. F. Stratford-- Turner, P. K. Torrington-- Doster, A. Upson, W. L. . 'Wallingford-- Burns, J. R. Waterbury-- Simpson, W. K. Stewart. C. W. Woodmont-- Williams, G. S. DELAWARE Milford-- Downing. C. B. Wilmington-- Anderson, P. R. Belt, N. O. Burke. J. J. Gawthrop, F. H. Granke, A. A. Hart, F. D. Hayman, A. E., Jr. Kershaw, M. G. Lownsbery, B. F. Parvis, R. S. Robinson, G. L. Schoenijahn, R. P. Steel. R. J. Norair, H. Nordine, L. F. Ourusoff, L. Parker, L. L. Peller, L. Phillips. W. L. Robinson. D. M. Sale, F. B. Stewart, J. N. Stokes, A. Sutter, E. E. Thomas. G. Thompson, N. S. Thuney, F. M. Tuxhorn, D. B. Urdahl, T. H. Vaughan, J. G., Jr. Walz, G. R. Watt, R. M.. Jr. Werner, J. G. Wilcox, C. M. DISTRICT OF COLUMBIA Washington-- . Addington, H? M. Beitzell, A. E. Bennett. C. Bensinger, M. Bomstein, W. Burkhart, E. M. ' Burns. H. J. Campbell, G. W. Canon, H. A. Cover, R. R. Crawford, A. C. Cullen, A. G. Day, I. M. _ Devore, A. B. ' DeWitt, E. S. Downes, H. H. Eagleton. S. P. Erisman, P. H., Jr. Espenschied, F. F. Febrey, E. J. Feltwell, R. H. Fife, G. D. Firestone, M. T. Fisher, J. T. Frankel, G. S. Frederick, W. L. Gardner, S. F. Geiger. R. L. Gregg. S. L. Gritzan, L. L. Grohs, C. E. Hall, W. L. Hanlein, J. H. Holmes. P. B. .Hoppe, M. F. Humphrey, L. G., Jr. Iverson, H. R._ Kajuk, A. E. Karsunky, W. K. Kiczales, M. D. Kingswell, W. E. Koster, H. H. Kugel, H. K. ' Lcser, F. A. Littleford, W. H. Lloyd, E. H. Lockhart, W. R. Loughran. P. H.. Jr. Loving, W. H. Malin, B. S. . McDonald, A. K. Merle, A. Meyers, J. Miller, G. F. Mitchell. A. E. Nelson, H. M. FLORIDA Brewster-- Homan. J. D. Fort Lauderdale-- Barth, J. W. Jacksonville-- Allen. W. W. Edge. A. J. Pastor. J. C. Varner. J. L. Miami-- Fried, H. V. Lingo. C. K. Rock, G. A. Ward. H. H. . Miami Beach-- . Friedman, D. II., Jr. Orlando-- Porter. C. W. Tampa-- .. Thomas, B. A: GEORGIA Atlanta-- Baker, C. T. Barnes. L. L. Blackman, A. O. Boyd, S. W. Brockinton, C. E., Brodnax, G. H., Jr. Clare, F. W.. Cole, C. B. Como, J. A. Crout, M. M. Driscoll, M. G. Foss. E. R. Gouedy, K. E. Gunnell, G. T. Hahn, R. F. Hamilton, L. L. Johnson, C. E. Kelley, R. D. Kent. L. F. . Klein. E. W. . Koch, A. H. ; Laseter, F. L. Lawrence, L; -F., Jr. .76 McCain. H. K. McKinney, W. J. Nolan, R. E. Pounds, C. A., Jr.Sherman, W. P. Sterner, D. S. ' Stotz, R. B. . ' Sudderth, L.. Jr. Templin, C. L. Tucker. Ti T. Yarborough, T. R. Augusta-- Akerman, J. R. Arndt, H. W. Brunswick-- Gilmore, J. L. College Park-- Blackshaw, J. L. Savannah-- Hamlin. J. B.. Jr. ILLINOIS Aurora-- Millen, R. J. Bloomington-- MaGirl, W. J. Nesmith, O. E. Soper, H. A.Whitmer, R. P. Calumet City-- Boyari S. L. Chicago-- Aeberly, J. J. Aikman, J. M. Ammerman, A. S., Jr. " Arenberg, M. K. Aronson, H. H. Bamond, M. J. Banach, C. J. Baumgardner, C.' M. Becker, W. A. Beery, C. E. . . . Benson, B. C. * Bernstrom, B. : Bevington, C. H. Bishop, M. W. . Black, F. C. Blaker, A. H. Blayney, W-. R. Borling, J. R. : Bowies, E. N. Boyle, J. R. Bracken. J. H. Bradley. J. M. Braun, L. T. . Brigham, C. M. . Brocha, J. F. Brooke, I. -E.Broom, B. A. . . Brown, A. P. Brown, J. S. Brown, T. Buckley, M. L. Burhatn. C. M.. Jr. Casey,. B. L. . Chapin, H. G. Christman, W. F. . Christopherson, A. E. ROLL OF MEMBERSHIP Clo, H. E. Close, P. D. Cook, H. D. Crone, C. E. Crump, A. L. * Cunningham, T. M. Dasing, E. Dauber, O. W. DeBerard, P. E. DeLand. C. W. Dunham. C. A. Emmert, L. D. Ericsson, E. B. Fatz, J. L. Fenner, N. P. Fergestad, M. L. Finan, J. J. Fleak, W. D: Floreth, J. J. Frank, J. M. Funck, E. H. Gardner, W.p Jr. Gaylord. F. H. Getschow, R. M. Goelz, A. H. Gossett, E. J, Gothard, W. W. Gotschall, H. C. Graves, W. B. Greenwood, O. J. Gregerson, G. Gustafson; C. A. Haas, S. L. Haines, J. J. Hale. J. F. ' Hanley, T. F.. Jr. Hart, H. M. Harvey, A. D. Hattis, R. E. Hayes. J. J. Hendrickson, R. L. Herlihy, J. J. Hill. E. V. Hines, J. C. Horner. S. D. Howard, F. L. .Howatt, J. Howell, L. Hubbard. G. W. Hustoel, A. M. Isett, W. M. Johns, H. B. Johnson, C. W. Keating, A. J. Keeney, F. P. Kehro. H. S. Keithley, F. R. King, A. C. Krez, L. Kuechenberg, W. A. Kummer, C. J. Lagodzinski. H. J. La Roi, G. H., II Lauterbach, H,, Jr. Lenone, J. M. Leuthesser, F. W., Jr. Lewis, S. R. Lockhart, H. A. Luders, R. H. Machen, J. T. Maier. H. F. Malone, D. G. Malvin, R. C. Manny, J. H. Martin, A. B. Matchett, J. C. Mathis, E. Mathis, H. Mathis, J. W. Mattingly, M. F. May, A. O. May, M. F. McCarthy. T. F. McCauley. J. H. McClellan. J. E. McDonnell, E. N. McDonnell, J. E. McRae, M. W. Medow, J. Merens. S. H. Mertz, W. A. Miller, F. A. Miller. R. T. Mifliken, J. H. Mittendorff, E. M. Morton, Pi S. Mueller. H. C. Muessig, J. W. Narowetz, L. L., Jr. Neiler, S. G. Nelson, R. O. Newport, C. F. Nightingale, G. F. Offeri, B. Olsen, C. F. Olson, B. Oosten, L. S. Peck. H. E. Philippi. J. J. . Piatnitza, J., Jr. Pickett, C. A. Pitcher, L. J. Pope, S. A. Powers, F. W. Prentice, O. J. Price, C. E. Priester, G. B. Rasmussen, R. P. Raymond. F. I. Reger, H. P. Rietz, E. W. Rist. L. M. Rottmayer, S. I. Runkel, C. Russell.-E. A. Ryerson, H. E. Sanders. C. M., Jr. Scheidecker, D. B. Schroeder, W. R. Schuetz, C. C. Schuler, W. B. Seelig, L. Shilling, H. C. Shultz, E. Solstad, L. L. Sommerfield, S. S. Spielmann, G. P. Stannard, J. M. Stermer, C. J. Stevenson, M. J. Sunderland, R. P. Sutcliffe, A. G. Swanson, N. W. Thinn, C. A. Thomas, R- H. Thoramen,-A. A. Thornton, W. B. Tobin, J. F. Tornquist, E. L. Tracy. W. E. Trumbo, S. M. Tupper, G. B. Turner, G. G. Van Alsburg, J. H. Vernon, J. R. von Rosenberg, P. C. Voss, W. W. Walters. W. T. Ward. O. G. Weil. M. Weil. M. I. Weinshank, T. Wendt, E. H. White. E. B. Whittington, J. A. . Widdowfield, A. S. Wills. F. W. Wilson. W. H. Wolff. P. P. Woll, W. M. Yeazel, G. A. Zack, H. J. Zimmerman, A. H. Colfax-- Scholl. H. O. Peoria-- Baird. S. A. Hauer, F. Meyer, F. L. Rochelle-- Caron, H. East St. Louis-- Cover, E. B. Lang, J. C. Edwardsville-- Rockford-- Braatz, C. J. Dewey, R. P. Stewart, D. J. Blackmore, J. J. Rock Island-- Evanston-- Kimble, C. W. Kearney, J. S. Springfield-- Maccubbin. H. A. Miller. J. E. Schoenhofen, L. H.. Jr. Sharp, J. E. White, E. A. Stacy, L. D. Stahl, W. A. ' Urbana-- Broderick, E 1 Galesburg-- Sidell.lP. A. Engdahl, R. Fahnestock, Fellows, J. R Konzo, S. Geneva-- Kratz, A. P. Atherton, G. R. Markland, C. E. Severns, W. H. Willard, A. C. Glencoe-- Hornung, J. C. Villa Park-- GlenJEllyn-- Armspach. O. W. Parsons. L. D.. Jr. Sherman, V. L. Waukegan-- Killian, T. J. Homewood-- Wilkinson, F. J. Kenilworth-- Storch, C. A. Kewanee-- 'Bronson, C. E. Dickson, R. B. Hartman, J. M. Pursell, H. E. Wilmette-- Marschall, P. J. Winnetka-- Killian, V. J. Prebensen, H. J. Zion-- Baughman, L. R. INDIANA Lake Forest-- Williams, D. C. Moline-- Beling, E. H. Nelson, H. W. Nelson, R. H. Mt. Vernon-- Beooist, L. L. Benoist, R. E. Oak Park-- Fitzgerald, M. J. Funk. D. S. May, E. M. Uhjhorn, W. J. Park Ridge-- Cochran, C. C. Heckel. E. P. Locke. J. S. Moore, R. E. Spielmann, H. J. Evansville-- Becker, R. K. Grossman, F. A. Fort Wayne-- Abramson, R. Goshen-- Shaw, B. E. Huntington-- Redrup, W. D. Smith, G. W. Indianapolis-- Ammerman, C. R. Clark. L. W. Fenstermaker, S. E. Fillo, F. B. Garber, W. E., Jr. Hagedon, C. H. Hayes, J. G. Hildreth, E. S. Niesse, J. H. Parker, P. E. Poehner, R. E. Supple, G. B. 77 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 La Porte-- Meyer, K. A. Shrock. J. H. Truitt, G. S. Lawrenceburg-- Bechtol, J. J. Michigan City-- Stockwell, W. Ri Westphal, N. E. Muncle-- Pfriem, P. G. Price, C. F. Peru-- Thrush, H. A. . Vincennes-- Wissing, C. B. Wabash-- Shivers, P. F. West Lafayette-- Forbes, H. B., Jr. MiUer, W. T. . Ruppert, C. F, Wiesner, B. K. IOWA Ackley-- . Nelson, 0.[G. Amana-- Foerstner, G. C. Zuber, O. Norman, R. A. Sandfort, J. F. Cedar Rapids-- Friedline, J. M. Des Moines-- Bartels, E. M. Borg, E. H. Campbell, B. Danielson, E. H. Daubert, L. L. . Delavan, N. B. * Elbert, B. F. Hedeen, L. E. Helstrom, C. W. Hennessy, W. J, Johnson, T. R.. Johnston, Mi T. Landes, .B. E. . LaRue, P. Leach, L. S. Olchoff. M. Schnell, R. H. Stiles, G. S. . Spring, C; L.' Triggs, F. E. Vaughn, F. R. : Walters,-A. L.'' ' Dubuque-- . . Brashaw, C. J.. Iowa City-- * Yuska, L. J. Marshalltown-- Shirley, W. B. Sioux City-- Hagan. W. V. Raven, A. H. Waterloo-- Herbert, R. M. Knox, J. C, Mitchell, J. A. Todd. M. L. Winterbottom, R. F. KANSAS Great Bend-- Morrison, W. L. Fort Leavenworth-- Foley, D. F. N Hutchinson-- Mann, A. R. Stevens, H. L. Junction City-- Froelich, H. A. Kansas City-- Allen. D. M. Angus, F. M. Jolley, E. M. Lawrence-- Machin, D. W. Robb, J. E. Sluss, A. H. ' Louisville-- Brown, J. S., Jr. Graham, J. M. Groot, H. W. Hellstrom, J. Hubbuch, N. J., Jr. Murphy, H. C. White. T. G., Jr. Paducah-- Thornburg, H. A. S. Fort Mitchell-- Kennedy, O. A*. Vine Grove-- Cropper, R. O. Seiter, J. E. Shepard. J. deB. Sklarevski, R. Smoot, T. H. Taze. E. H. Vance, L. G. Vincent, P. J. . Whiteley, S. -M. Bethesda-- - Goodwin, E. W. Nolan, J.J., Jr. ' Schlichter, C. F* Smith, S. Stock, C; S. - Terhune, R. D. . Brooklyn Park-- Rodgers, J. S. . LOUISIANA Chevy Chase--Thulman, R. K. New Orleans-- .. Gamble. C. B. Gammill, O. E., Jr. Herman, N. B. May, G. E. McLaren, F. S. Moses, W. B., Jr. Ryan, J. D.` Shepperd, P. D. Shreveport-- Fitzgerald, W. E. Jones, H. L. Zwally, A. L. MAINE Bangor-- Prince, R. F. Lewiston-- . College Park-- Gifford, W. R. ; Cumberland-- Griffith, C. A. Hyattsville-- _ Baldwin, K, F;, Jr. Kensington--. Spurney, F. E. Rockville-- ' Brunett, A. L. Sliver Spring- Black, F. M.. Dill, R. S. . : : Fineran, E. V. Shuman, L. . Stack, A. E. Neodesha-- Berzelius, C. E. Russell-- Danielson, E. B. Danielson, L. C. Salina-- Bachofer, H. A., Jr, Ryan. W. F. . Wichita-- . . Buckley, D. J. . Droppers, C. J. KENTUCKY " Fort Thomas-- Stevens, W. R. Lexington-- Cabot.M. A. May, J. W. O'Bannoa, L. S. West, P. Fowles, H. H. Portland-- Fels, A. B. Merrill, C. J. . . South Portland-- Mitchell, C. H. MARYLAND Annapolis--. .. Gale, H. A. Baltimore-- . Collier. W. I., Crosby, E. L.. . Dorsey, F. C. Dressell, R. E. Hunt, M.\ Lee, J. A. Leilich, R. L. McCormack, D. Nest, R. E. Posey, J. ` Reinoldi, C. ' Robinson, E. R. --Takoma Park-- Borkat, P/ . Croney, P. A. MASSACHUSETTS Andover-- : - Wilson, A. M. Arlington-- . ... Sessler, R. E. Shaw, N. J. H. Arlington Heights-- Tarr, H. M.'- Belmont-- . Kellogg, A. Spence, R. A. . Boston-- Archer, D.'.M. Blakeley, H; J. Brinton, J. W. Brissette, L. A. 78 ROLL OF MEMBERSHIP . i Bryant, A. G. Lawrence-- Wakefield-- Basse, H. Colby, J. H. Cummings, C. H. Bride, W. T. Bennitt, G. E. Champlin, R. C. Clar, R., Jr. Donohoe, J. B. Drinker, P. Leominster-- Watertown-- Clark. E. H. Connell, R. F. Edwards, D. J. Kern, R. T. Wiegner, H. B. Coon, T. E. Foulds, P. A. L. Cummins, G. H. Franklin, R. S. Gleason, G. H. Hashagen, J. B. Jennings, R. A. Lynn-- Farrow, H. L. Feehan, J. B. Wellesley-- Millard, J. W. Darlington, A. P. Dauch, E. O. Davis, G. L., Jr. Deppmann. R. L. Jennings, W. G. Wellesley Hills-- Dickenson, F. R. i Kelley, J. J. Kimball, C. W. Licandro, J. P. Little, D. H. McCoy, T: F. Merrill, F. A, Malden-- Denham, H. S. Melrose-- Gerrish, G. B. Barnes, W. E. West Roxbury-- McCafferty, J. E. McPherson, W. A. Doyle. B. J. Dubry, E. Elliott, N. B. Estep, L. G. Feinberg, E. Flink, C. H. Nee, R. M. Pritchard, W. J. Gifford, E. W. Pohle, K. F. Stetson, L, R. Swaney, C. R. Tuttle, J. F. Milton-- Austin, W. H. Corey, G. R. Woburn-- Parker, P. Giguere, G. H. Goss, M. H. Hamaker, A. C. Harrigan, E. M. Waterman, J. H. Harrigan, E. R* Yaglou, C. P. Newton Centre-- Worcester-- Hesselschwerdt, A. L., Jr, Murray, J. J. Delany, J. V. Heydon, C. G. Bridgewater-- Kolb. R. P, Hogan. E. L. ' Beaulieu, A. A. Cambridge-- Newtonville-- Emerson, R. R. Jones, W. T. Wechsberg, O. Hubbard, N. B. Hughson, H. H. Hutzel, H. F. Hyde, E. V. Flint, C. T. Holt. J. Norwood-- MICHIGAN Ibison, J. L. Johnson, F. W. Hoyt, C. W. Epple, A. B. Kaufman, H. J. Moore, H. C. Peterson, C. M. F. Saurwein, G. K. Staszesky, F. M. Touloukian, Y. Turner, J. Wilkes, G. B. Pittsfield-- Nicholls, J. M. Wagner, E. A. Woodger, H. W. Albion-- Gable, H. R. Alma-- Gerhard, D. H. Kilner, J. S. Kincaide, M. C. Kirkpatrick, A. H. Knapp, A. E. Knibb, A. E. Lance, J. F. Lautz, F. A. ' Chelmsford-- Reading-- Ingalls, F. D. B. Ann Arbor--' Backus, T. H. L. Lewis, G. M. Linsenmeyer, F. J. Livermore, J. N. Ridley, W. H. Revere-- ' Bichowsky, F. R. Emswiler, J. E. Lowe, R. A. Luty, D. J. Chelsea-- Hochman, E. Cochituate-- Ahearn, W. J. - Dedham-- Lincoln, R. L. Dorchester-- Goodrich, C. F. Hosterman, C. O. Shaer, I. E. Brayman, A. I.. Roslindale-- . Finnerty, J. A. Larson, C. W, Roxbury-- Madden, J. J. Sharon-- Nelson, A. W. Shirley-- Boyden, D. S. Falk, D. S. Kessler, C. F. Marin, A. Battle Creek-- Christenson, H. Dempsey, S. J. Dyer, W. S. `Bay City-- Gray, J. W. Henry, E. C. Witmer, H. S. Birmingham-- Lyke. H. W. Mabley, T. H. MacMillan, A. R. Maier, G. M. Martel, C. L. Marzolf, F. X. McCrea, J. B. McDonald, J. J, McGaughey, H. M. McGeorge, R. H. Mclntire. J. F. McLean, D. ' Metcalfe, C. . Middleton, D. K. Miller. R. E. Milward, R. K. Morgan, R. W. East Lynn-- Lauckner, C. G., Ill Somerville-- Akers, G. W. . Hadjisky, J. N. Hyde. E. F. Morse, C. T. Morse, L. S., Jr.- Nutting. H. G. D. Sheffield, R. A. Root, E. B. Oberschulte, R. H. Essex-- Wonson, A. S., Jr. Fitchburg-- lllig, E. E. Illig, W. R. Karlson, A. F. McKittrick, P. A. Harwich Port-- Maxwell, G. W. Hyde Park-- Bartlett, A; C. Ellis* F. R. Scalingi, C. R. Whitten, H. E. South Braintree-- Chenoweth, D. M. South Hamilton-- Mandell, T. P. Springfield-- Cooper, W. B. Cross, R,. E. Holmes, R. E. Huggins. L. G. Leland, W. B. Murphy,.W. W. Clarkston-- Volberding, L. A. Detroit-- Adam, R. W. Anderson,' E. J. Annas, H. C. Baldwin, W. H. Barth. H. E. Barton, J. Bassett, J. W. Bay. C. H. . Biggers, R. H. Bishop, F. R. Blackmore, F. H. Boales, W. G. .. O'Gorman, J. S. Old. W. H. O'Rourke, H. D., Jr. Paetz, H. E. Parrott, L. G. Partlan, J. W. - Patterson, F. H. Pavey, C. A. Pike, W. . Purcell, F. C. Randall. R. D. Randall, W. C. Reader, J. T. Rose, W. H.. Jr. ; Sanford, S. S. Schechter, J. P. Schmidt, K., Jr. Schultz, S. F. . . 79 HEATINC VENTILATING AIR CONDITIONING GUIDE 1940 Shea. M. B. Sheley. E. D. Shields. C. D. Smith. W. O. Snyder, J. W. Soeters, M. Spitzley, R. L. Spurgeon, J. H. Stiles. R.. Jr. Taylor, H. J. Toonder, C. L. TutUe, G. H. Van Nouhuys, H. C. Waid. G. H. Walker. J. H. Weinert, F. C. Whelan. W. J. White, E. S. Winans. G. D. Dowaglac-- Cunningham, J. S Deming, R. E. ` Harden, J. C. Torr. T. W. Woodhouse, G. D. East Lansing-- Miller, L. G. Pesterfield, C. H. Escanaba-- Bernhard. G. Ferndale-- Mally, C. F. Flint-- Hendriksen. L. Grand Haven-- ` Erickson, E. V. Grand Rapids-- Boot, A. ' Bradfield, W. W. Bratt, H. D. Dykman, J. G. Gair. K. B. Graff, W. F. Marshall, O. D. Morton, C. H. Osberger, T. L. Stafford, T. D. Thoman, E. O. Todd. S. W. Warren, F. C. Worthing, S. L. Ziesse. K. L. Grosse Pointe Park-- Buckeridge, V. L. Feely. F. J. Kaiser, F. McConachie, L. L. H ermansville-- Voorhees. G. A. Highland Park--. Harrower, W. C. Wilde, R. S. M. Holland-- DeRoo. W. C. Houghton-- Seeber, R. R. Iron Mountain-- Eisele, L. G. Kalamazoo-- Brinker, H. A. Downs. S. H. Hotop, N. C. McConner, C. R. Metzger. H. J. Schlichting, W. G. Temple, W. J. Wilson. R. W. Lansing-- Distel, R. E. Hill, V. H. McLouth, B. F. Parsons, R. A. Mt. Clemens-- Bailey. E. P. Muskegon-- Leigh, R. L. Young, H. J. Muskegon Heights-- Reid. H. F. Pleasant Ridge-- Williams, F. H. Pontiac-- Singleton, J. H. Trzos, O. A. Royal Oak-- Burch, L. A. Helmrich, G. B. Keyser, H. M. Saginaw-- Witheridge. D. E. Three Rivers-- Hall. C. H. MINNESOTA Bayport-- Swanson, E. C. Duluth-- Foster, C. Burritt, C. G. Campbell, R. L. Caple, I. Carlson, C. O. Chalmers, C. H. Comb, F. R,, Jr. Copperud, E. R. Cvmming, F. J. Dahlstrom, G. A. Davidson, J. C. Dever, H. F. Dovolis, N. J. Doxey, H. E. Edelman, B. P. Fedders, M. P. Forfar, D. M. Francis, P. E. Gausewitz. W. H. Gerrish, H. E. Gordon, E. B., Jr. Gross, L. C. Haley, R. T. Hall. J. R. Hanson, L. C. Hanson, L. P. Harris, J. B. Hawkinson, C. F. Helstrom, H. G. Herbacek, E. E. Hitchcock, P. C. Huch, A. J. Jordan, R. C. King, R. L. Kingsland, G. D. Knapp. D. S. ' Knowles, E. L. Kuehn, W. C. Lange, F. F. Larson, C. P. Legler, F. W. Lilja, O. L. Lund, C. E. Marshall, S. C. McDonald, T. Mills. H. C. Morgan; G. C. Morton, H. S. Newton, A. B. Orr. G. M. Ostdahl, H. E. Petersen, C. P. Proebstle, L. Reisberg, L. K. Roberts, H. P. -- Rowley, F. B. Schad, C. A. Schembeck, F. H. Schultz, A. W. Seelert, E. H. Shipley, S. C. Spencer, J. B. Stafford. J. F. Stiller, F. W. Sturm, W. Sutherland, D. L. Swanson, D. F. Sweeney, R. H. Swenson, J. E. Uhl, E. J. Uhl. W. F. Wallace, H. P., Jr. Willis, L. L. Mankato-- Forderbruggen, K. J. Owatonna-- Anderson, G. A. M. Minneapolis-- Algren, A. B. Bell. E. F. Bensen, C. L. Benson, M. L. Betts, H. M. Bjerken, M. H. Bredesen, B. P. Bums, E. J. Rochester-- Adams, N. D. St. Paul-- Anderson, D. B. Backstrom, R. E. Bauer, A. E. Bean, G. S. 80 Cook, G. E. Diamond, D. D. Estes. E. C. Fitts, C. D. Gausman, C. E. Hickey, D. W. Jones, E..F. Lynn, R. G. McNamara, W. Mitchell, J. G. Oberg, H. C. - . Persson, N. B. Ruff, D. C. Sanford, A. L. Tilton, N. K. Winterer. F. C. Wunderlich, M. S. Spring Park-- Streater, E. C. Wayzata-- Heberling. C. W. Winona-- Hamerski. F. D. MISSISSIPPI Jackson-- Light, J. C. State College-- Bailey. C. F. MISSOURI Clayton-- DuBois. L. J. Drexel-- Baender, F. G. Ferguson-- Szombathy. L. R. Glendale-- Nelson. C. L. Hickman Mills-- Case, D. V. Independence-- Cook. B. F. Jefferson City-- Woodman. L. E. Joplin-- Jones, J. T. McMullen. E. W. Kansas City-- Arthur, J. M., Jr. Ball, W. Barnes. A. R. Betz. H. D. Caleb. D. Cameron, W. R. Campbell, E. K. Campbell. E. K., Jr. ROLL OF MEMBERSHIP Campbell, R. P. Cassell. W. L. Chase, L. R. Clegg, C. Dawson, T. L. Dean, F. J., Jr. Dean, M. H. DeVilbiss, P. T. Disney, M. A. Dodds. F. F. Downes, N. W. Ellis. L. W. Farber, L. M. Fehlig, J. B. Flarsheim, C. A. Forslund, O. A. Gillham, W. E. Gould, H. E. Harbordt, O. E. Holuba, H. J. Kitchen. J. H. Mahon, C. A. Maillard, A. L. Marchio, E., Jr. Marston, A. D. Matthews, J. E. Millis, L. W. Nottberg, G. Nottberg, H. Nottberg, H., Jr. O'Dower, H. J. Painter, D. H. Pellmounter, T. Peltzman, J. L. Pexton, F. S. Rivard, M. M. Russell, W. A. . Ryan, J. B. * Sheppard, F. A. Stephenson, L. A. Weiss, C. A. White, H. S. Williams. A. E. Wright, H. H. Zink, D. D. Liberty-- Kurek, T. C. Maplewood-- Curry, R. F. Siegel. W. A. Mexico-- Badaracco, J. A. Normandy-- Dulle, W. L. Richmond Heights-- Siegel, D. E. St. Joseph-- Harton, A. J. ` Zurow, W. St. Louis-- Barry, J., Jr. Bayse. H. V. Boester, C. F., Jr. Bradley, E. P. Carlson, E. E. Carter, J. H. - Clarkson, J. R. Cooper, J. W. Corrigan, J. A. Davis, C. R. Dreher, L. F. Driemeyer, R. C. Evans, B. L. Fagin, D. J. Foster, J. M. : Gilmore, L. A. . Grossenbacher, H. E. Grossmann, H. A. Haller, A. L. Hamig, L. L. . Hester. T. J. Horch, G. E. Kella, W. B. Langenberg, E. B. Laskaris, N. G. Laufketter, F. C. Malone, J. S. Matousek, A. G. McLarney, H. W. McMahon, T. W. Miller. J. E. Moon. L. W. Norris, W. P. Oonk, W. J. Pellegrini, L. C. Rodenheiser, G. B. Rosebrough, J. S. Scherrer, L. B. Sharp, H. C. Simons, B. C. Sodemann, W. C. B. Sodemann, Pi Stammer, E. L. Sydow, L. J. . Tenkonohy, R. J. Warren, J. S., Jr. Weber, E. F. Springfield-- James, R. E. . Karchmer, J. H. University City-- Carlock, M. F. Falvey, J. D. Webster Groves-- Harbaugh, J. W. Hartwein, C. E. Myers, G. W. F. Ronsick. E. H, Rosebrough, R. M. Lincoln-- Green, E. W. King. L. D. Ress, O. J. Shapiro, M. M. Tapley, M. S. Williams, D. D. Omaha-- Banner, F. L. D. Eaton. B. K. Frederick, K. C. GoU, W. A. Kleinkauf, H. Knepper, H. H. Larkin, P. Lycan, L. K. Malcolm, B. L. Mathis, j. Merwin, G. E. Millard, E. L. Moffitt, L. C. Olson, M. J. Organ, F. Peiser, M. B. Reifschneider, J. Rigby, R. A. Sallander, H. A. Schwartz, N. E. Solzman, I. I. Stanfield, R. E. Waddington, B. C. White. W. R. Scottsbluff-- Davis. O. E. Prawl, F. E. NEW HAMPSHIRE Elkins-- Baker, R. H. NEW JERSEY MONTANA Big Timber-- Strickland, A. W. Billings-- Cohagen, C. C. Young. F. H., Jr. Great Falls-- Ginn. T. M. NEBRASKA Clarks-- Manning. W. M. Columbus-- Ragatz. T. E. Hastings-- Swingle, W. T. Asbury Park-- Strevell, R. P. Atlantic City-- Strouse, S. B. . Bayonne-- Schwartz, J. Belleville-- Thornton, T. L. Blackwood-- Weid. H. L. Bloomfield-- - Burges. J. H. M. Faust, F. H. Harrington, E. 1 Jackes. H. D. McLenegan, D. W. Tenney, D. Bogota-- Griess, P. G. 81 Camden-- Brown, W. M. Coward, C. W. Kappel, G.`W. A. Lanning, E. K. Plum, L. H. Webster, E. K. Webster, W., Jr. Cliffslde Park-- Butler, P. D. Clifton-- Hilder. F. L. Collingswood-- Mohrfeld, H. H. Cranford-- Ray. G. E. Dover-- Hedden, W. M. East Orange-- Ferguson, R. R. Gombers, H. B. Maddux, O. L. Reilly, J. H. Schroth, A. H. Settelmeyer, J. T. Tallmadge, W. Turno, W. G. W. Wildman, E. L. Elizabeth-- Anderson, J. W. Cornwall, G. I. Wheller, H. S. Essex Fells-- Soule. L. C. Stacey, A. E., Jr. Fair Haven-- Mytinger, K. L. Freehold-- Buck, D. T. Glen Ridge-- Stark, C. E. Haddonfield-- Buzzarcf, F. H. Hasbrouck Heights-- Goodwin, S. L. Haworth-- Sharp. J. R. Irvington-- Reinke, A. G. Stengel, F. J. Jersey City-- Borak, E. Jones, H. L. Kunzog, T. W. Ritchie, W. Walterthum, J. J. p HEATINC VENTILATING AIR CONDITIONING CUIDE 1940 Kearny-- Shaffer, C. E. Leonla-- Close, R. Lyndhurst-- Ehrlich, M. W. Maplewood-- Kepler, D. A. Woolley, J. H. Merchantvilli Binder, C. G Montclair-- Bentz, H. Broome, J. H. Scarlett, W. J. Morristown-- Roy, A. C. Newark-- Albright, C. B. Bryant, P. JCarey, P. C. Haitmanek, L. M. Kruse, W. C., Jr. Katinski, W. V. Leinroth, J. P. Morehouse, H. P. Patrick. H. M. Ray, L. B. Raymer, W. F., Jr. Steinmetz, C. W. A. Zemelman, I. M. New Brunswick-- Auchmoody, F. W. Wolin, M. W. North Arlington-- Bermel, A. H. North Plainfield-- Seal, A. T. Nutley-- * Atkins, T. J. Morris, C. R. . Orange-- Crawford, J. H., Jr. Paterson-- Bannon, L. E. Cox, H. F. Frank, O. E. Perth Amboy-- Simkin, M. Plainfield-- Pond, W. H. Red Bank-- Isaacs, H. A., Jr. Ridgefield Park-- Davis, A. C. Ridgewood-- Connell, H. Fitts, J. C. Miller, A. T. Wallace, D. R. Roselle-- Snavely,- E. R. Scotch Plains-- Scribner, E. D. Somerville-- Van Nuys, J. C. South Orange-- Browne, A. L. Feldermann,' W. Summit-- Oaks, O. O. Teaneck-- Heebner, W. M. Trenton-- Plaag, A. F. Union-- Edwards, L. V. Lyman, S. E. Union City-- Matheka, C. R. Taveroa, F. F. West Englewood-- Gumaer, P. W. Steinke, B. J. Westfield-- Hach, E. C. Hansler, J. E. West New York-- Stinard, R. L. West Orange-- Adlam, T. N. NEW YORK Albany-- Bond, H. A. Dick, A. V. Dutcher, H. S. Johnson, H. S. Lewis, H. F. Murray, T. F. Taggart, R. C. Teeling, G. A. Westover, W.. Yerkes, W. L. Bedford Hills-- Waters, F. A. Bronxville-- . Bishop. C. R. Dornheim, G. A. Groves, S. A. Brooklyn-- Addington, H. B. Balsam, C. P.. Bieringer, F. A. Bigolet, L. Brex, I. E. Campbell, R. E. DeSomma, A. E., Dwyer, T. F. Fidelius, W. R. Goldberg, M. Gornston, M. H. Goutding, W. Harsch. R. J. Hollister, N. A. Jacobi, B. A. Janet, H. L. Josephson.S. Kadel. G. B. Leventhal, B. Levine, C. Phillips, F. W. Potter. J. R. Ritchie. E. J. Rose, J. C. Schechter, J. E. Stalb, J. G. Tusch, W. Wachs, L. J. Weissblatt, N. Wilson, A. Buffalo-- Adema, G. E. Beman, M. C. ' Berringer, S. H. Booth, C. A. Cherry, L. A. Cheyney, C. C. Currier, C. H. Davis, J. Day, H. C. Drake, G. M, Eisele, W. S. Eutsler, E. E.t Jr. Farnham, R. . Farrar, C. W. Freitas, L. J. Grieves, T. R. Harding, L. A. Hawk, J. K. Heath, W. R. Hedley, P. S. Hirschman, W. F. Holt. W. H. Hurwich, S. B. Jackson. M. S. Jenkins, F. H. Karaman, A. R. Landers, J. J. Lenihan, W. O. Lighthart, C. H. Long, H. P. Love, C. H. Madison, R. D. Mahoney, D. J. Moesel, F. A. Mosher, C. H. 82 Osborne, S. R. Pleuthner, R. L. Reif, A. F. Reif. C. A. Roebuck, W., Jr. Ruff, H. A. Schafer, H. C. Schmidt, H. Seelbach, H., Jr. Seyfang, W. G. Shelney, T. Siegel, R. C. Spencer, W. E. Strouse. S. W. Voisinet, W. E. Walker, E. R. Wendt, E. F. Whitt. S. A. Yager, J. J. . Zolitsch, H. G, Gooperatown-- McGown, F. H.; Jr. Croton-- Elliott, I. Dobbs Ferry-- Hewett, J. B. Dunkirk-- Mayne, W. L. Eden-- Ensign, W. A. ' Elmira-- Davis, B. C. Glenwood Landing-- Wittig. F. E. Hastings-on-Hudson__ Reynolds, T. W. Irvington-- Bastedo, A. E. Ithaca-- Elwood, W. H. Frederick, H. W. Sawdon, W. M. Williams, J. W. Woods, E. H. Kendall-- Stangland, B. F. Kenmore-- Candee, B. C. Criqui, A. A. , Heikkila, F. E. Mollenberg, H. J. Snyder, J.. S. Sommers, W. J. Lockport-- Johnston, R. M. Saunders, L. P. T }J' ROLL OF MEMBERSHIP Long Island-- Pinto. C. B. Cullin, W. W. Olvany, W. J. Alt, H. L. (St. Albans) Apt, S. R. (Flushing) Bachmann, A. J. (Jamaica) Ballman, W. H, ' (Long Island City) Bastedo, G. R. (Jamaica) Ranzinger, G. (Whitestone) Raynis, T. (Manhasset) Schermer, R. (Elmhurst) Skidmore, J. G. (Long Island City) Daly. R. E. Darts, J. A. Davis, C. Davison. R. L. Demarest, R. T. Denny, H. R. ' Deterling, W. C. Dodge, H. A. Donnelly, R. Downs, C. R. Ortiz, J. V. Page. V. C. Parker, D. F. Patorno, S. A. S. Pihlman, A. A. Place, C. R. Poliak. R. Purinton, D.f Quirk, C. H. Raisler, R. K. (Richmond Hill) Spoerr, F. F. Driscoll, W. H. Ramsay, J. W. Belsky, G. A. (Jamaica) Eadie. J. G. Rather, M; F. (Valley Stream) Stellwagen, F. G. Eils. L. C. Reid, H. P. j Blackburn, E: C., Jr. (Garden City) Bloom, L. ' (Freeport) Bonthron, R. C. (Hempstead) Cameron, R. T. (Woodhaven) Sterne, C. M. (Long Island City) Marshall, R. D. (Port Washington) Richfield, N. H. (Floral Park) Elliott, L. B. Engle, A. Etlinger, M. J. Faile, E. H. Fay, F. C. Feder, N. Feldman, A. M. Fiedler, H. W. . Reis, R. Reynolds. W. V. . Ritter, A. Rodman, R. W. . Rosenberg, P. . Ross, J. O. . . Roth, C. F. Salter, E. H. (Southampton) Carbone. J. H. Rudd, D. J. (Babylon) Fischer, L. . Fleisher, W. L. Samuels, S. Sanbern, E. N. (St. Albans) Schwartz, M. Foster, J. G. Sawhill, R. V. Clark, A. N. (Far Rockaway) Friedman, M. Schoepflin, P. H. (Manhasset) Crone, T. E. (Jackson Heights) Eastwood, H. F. (Merrick) Franck, P. (Jackson Heights) Freeman, A. W. ' (Jackson Heights) Fritz, C. V. : Thomson, T. N. ' (Huntington) Trambauer, C. W, (Whitestone) Tucker, F. N. (Freeport) Vervoort, E. L. - (Rockville Centre) Wade, R. H. . (Laurelton) Fuller, C. A. Giannini, M. C. Gctterman, H. Goldsmith, E. Gordon, P. B. Greenberg, I. Greenburg, L.' Hall, C. J. Hanburger, F. W. Hateau, W. M. Heckler, S. Schulze, B. H. Scott, A. F. H. Scott, G. M. Sears, C. B. Seelig, A. E. Sellman, N. T. Senior, R. ,L. Siebs. C. T. Sklenarik, L. Smith, M. S. Sobel, F. (Freeport) Wallace, G. J. Heibel, W. Sternberg, E. Galloway, J. F-. (Kew Gardens) Graber, E. (Douglaston) . Hiers, C. R: (Great Neck) Hoehl, E. R. (GardenCity) Holland, G. R. (Jackson Heights) (East Elmhurst) Whittaker, W. K. (St. Albans) Mt. Vernon-- Cribari, H. E. Freitag, F. G. Herske, A. R. Morse, F. W. Heller, J. A. Henry, A. S., Jr. Hering, A. Herkimer, H. Herty, F. B. High. J. M. Hinrichsen, A. F. Hirsch, M. H. Hobbie, E. H. Hoffman, C. S. Honerkamp, F. ' Still, F. R. Strock, C. ' Strunin, J. Syska, A. G. Taylor, F., Jr. Tiltz, B. E. Timmis, W. W, TuthiU, A. F. Tyler, R. D. Vetlesen, G. U. Wadsworth, R. H. Jalonack, I.'G. . Hosking, H. L. Waechter, H. P. Qamaica) . Kahn, C. R-, Jr. (Woodmere) Kaiser, C. W. (Woodside) Keller, G. A. (Wantagh) Kern, J. F., Jr. (Jamaica) . Klenert, W. / New Rochelle--- Abrams, A. Farley, W. F. Fitz, J. C . Mank, M. Rose, H. J. New York-- Adams, E. E. Hotchkiss, C. H. B. Hutcheon, C. R. Hyman, W. M. dTssertelle, H. G. Iverstrom, C. jacobus. D. S. James, J. W. Jarcho, M. D. Kelly, C. J. Kimball, D. D. Koehler, C. S. Walker, K. Wallace, G. N. Walther, F. G. Walton, C. W,, Jr. Waring, J. M. S. Wasson, R. A. ' Wheeler, J., Jr. Wilder. H. P. Williams, H. E, (Flushing) . ` Addams, H. Kuhlmann, R. Willner, I. . Landewit, C. J. Adler. H. Kunen, H. Wolf. P. . ... (St. Albans) Ashley, E. E. Kurth. F. J. Wrightson, W. T. Lane, D. D. (Elmhurst) Lang, J. (Richmond Hill) . Lewis. C. A. (Astoria) Baker, H. L., Jr. Baker, W. H.. Jr. - Barbieri, P. J. Baum, A. L. Bearman, A. A. Beebe, F. E. W. Bennett, E. A. Lawrence, F. D. Lucke, C. E. Markush, E. U. Martens, E. D. Martin, G. W. Mayette, C. E. McCann, F. D. ; ' ' Niagara Falls-- Kessler, M. E. . Woolcock, E. MacWatt, D. A. . Berman, L. K. McClintock, W. North Tairytown-- (Great Neck) Magee, K. B. Bianculli, V. A. Blackmore. J. J. McEwan, E. E, McLeish, W. S. Weiss, A. P. (Astoria) Bodinger, J. H. Meinke, H. G. Magnusson, N. Bolton. R. P. Meyer. H. C., Jr. North Tonawanda-- (Jamaica) Meyer, C. L. (Hollis) (Hollis) Bond, H. H. Brown, D. ' Buensod, A. C. Carpenter, R. H, ' Cassell. Q. E. R. Charlet, L. W. Milener, E. D. Miller, C. A. Miller, J. Montgomery, O. C. Munier, L. L. Munkelt, F. H. Conaty, B. M. Ossining-- Dee. L. H. Olsen, G. E. Chase,.C. L. Murphy, J. R. (Arverne)Pabst, C. S.; Citron. D. J. Clay, W. Offner, A. J. Oldes, W. E. Oswego-- (Woodhaven) Cued, V. J. Olson, R. G. Mohn, H. L. 83 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 Pelham Manor-- White. E. G. Potsdam-- Armstrong, E. T. Rochester-- . Betlem. H. T. Cook, R. P. Dickason, G. D. Eschenbach, S. P. Hakes, L. M. Hutchins, W. H. Kimmell, P. M. Leonhard. L, W. Lewis, C. E. ' Stacy, S. C.' Treadway, J, Q. Vidale. R. Wilder, E. L. . Rome-- Lynch, W. L. Scarsdale-- Gumming, R. W. Schenectady-- Hunziker, C. E. Spitzley, J. H. Welch, L. A., Jr. Snyder-- Gilford, C. A. Staten Island-- Callahan, P. J. (Great Kills) Frimet, M. (West Brighton) Johnson, E. B. (W.'New Brighton) Pfuhler, J. L. (W. New Brighton) Pietsch, J. A. (New Brighton) Ruggles, R. F. (Randall Manor) Sherbrooke, W. A. (Tottenville) Vivarttas, E. (W. New Brighton) Volkhardt. A. N. (Rosebank) Vroome,"A. E. (Prince Bay) Wood. R. A. (W. New Brighton) Suffern-- Barnum, M. C. Syracuse-- Acheson, A. R. Ashley. C. M. Avery, L. Cady, E. F. Carrier. W. H. Cherne, R. E. Cox. T. M.. Jr. Day, V. S. Dunne, R. V. Evans, E. C. French. D. Graham, W. D. Hockensmith, F. E. Ingels, M. M. Keane, G. F. Kubasta, R. W. Lewis, L. L. Lyle, J. I. Murphy, E. T. Schoeffter, H. M. Sheldon. N. E. Taliaferro, R. R. Traynor, H. S. VVoese. C. F. Tonawanda-- Karlsteen, G. H. Utica-- Knapp, J. H. Steinhorst, T. F. Valhalla-- Mehne, C. A. Watervliet-- Schubert, A. G. White Plains-- Baker. T. Durkee, M. E. Zibold, C. E. WUUamsville-- Stevens. A. L. Yonkers-- Goerg, B. Harmonay, W. L. Kelly. J. G. Rainger, W. F. Werker, H. Zuhlke, W. R. NORTH CAROLINA Asheville-- Wilson. W. E. Charlotte-- Brandt. E. H., Jr. Hill. H. H. Hodge. W. B. Muirheid, J. G Petty, C. E. Warren, R. M., Jr. Durham-- - Cooke, T. C. McDowell, H. L. Mills, R. H. Reed. F. J. Wallace, W. M., II Greensboro-- Adams, C. Z. Davis, D. W., Jr. Guest,.P. L., Jr. Harding, E. R. Hoffman, H. Oertel. F. H. E. Patterson/G.' P. Hickory-- Daddario, F. T. High Point-- Gray. W. E. Lewis. W. W.. Sr. Raleigh-- Rice, R. B. Vaughan. L. L. Sproull, H. E. Sigmund, R. W. Silberstein, B. G. Sutfin, G. V. . Thompson, E. B. Washington, L. W. Ward, F. J. White, E. D. Williams, E. C.. Winstel. F. E. , Winther, A. Wright. K. A. . Cleveland-- Winston-Salem-- . ' Bahnson, F. F. : Brown, M. D. Cornwall, C. C. Kaczenski, C. Marshall, J. Page. A. OHIO Akron-- McEihaney, G. W. Turk. L. Ashland-- Rybolt, A. L. Chagrin Falls-- Kofoed, V. B. ' Wilson. R. A. Cincinnati-- Bird. C. Boyd, T. D. Buenger, A. Coombe, J. Cott. W. B: - - Donetson, W. N. DuChateau, M. F. Edwards, A. W. Fenker, C. M. Gannon. R. R. Green. W. C. Hard, A. L. Helbura, I. B. Houlis, L. D. Houiiston, G. B. Hudepohi, L. F. Hust, C. E. Hutchinson, B. L., Jr. Jennings, H. K. Junker. W. H. Kiefer, C. J. Kilday, J. A. Kinney, A. M. Kramig, R. E., Jr. Leupold. G. L. Lewis, H. E. ' Mason. G. C. Mathewson. M. E. Mills, C. A. Moore, H. W. Motz, O. W. Mursinna, G. P. Pillen. H. A. Pistler, W. C. Richard. E. J. Royer. E. B. Ruff, A. G. Auer, G. G. Avery, L. T. Baggaley. W. Beach. W. R. Berger, J. L. Cary, E. B. Cheeseman, E. W. Cohen, P. ' Conner, R. M. Cushing. C. F. Curtis, H. F.* Downe, E. R. Evans. W. A.' Eveleth, C. F. Friedman, A. Gayman, P. D. Geltz, R. W. Gottwald, C. Gray. E. W. Hall, N. H. Harvey, L. C- Heisterkamp, H. W. Kaercher, C. M. H. Jones, J. P. ` Kitchen. F. A. ' Klie, W. Levy, M. I. Mannen, D. E., Jr. McKeeman, C. A. Moore, W. R. Nachman, G. P. Nessell, C. W. Nobis. H. M. Pogalies, L. H. Powers, L. G. Quick, B. A. Rowe, W. M. Slawson, L. E. Smith, W. D. Southmayd, R. T. Taze, D. L. . Tuve, G. L. ' Vanderhoof, A.'L. Webb. E. C. : Weldy. L. O. Wetzell, H. E. Wilhelm, J. E. Wootan, C. C. ` ' Wright, D. K.. Jr. Young, E. O. Cleveland Heights-- Black, J. M. Clark, R. L. Davis. R. G. Rhoton, W. R. Sogg, A. Columbus-- Allonier, H. R. Breneman, R. B. Brown, A. I. Cross, R. C. Denise, J. R. Dolson, C.-N. Gowdy, A. C. Myler. W. M.. Jr. 84 ROLL OF MEMBERSHIP Oelgoetz, J. F.Poling, D. B. Sherman, R. A; Somers, W. S. Wiliiams,-A. W. Wyatt, DeW. H. Cuyahoga Falls-- Humphrey, D. E. Dayton-- Baker, I. C. Chapman. W. A., Jr. Everetts, J., Jr. Fuller, E. W. Gibbons, M. j. Godfrey, J. E. Gonzalez, R, A. Hull. H. B. Hutchings, R. L. Kucher, A. A. Kuempel, L. L. LaSalvia, J. J. Linebaugh, J. E. Uvar, A. P. Johnson, R. F. Ralph, D. S. Smith, N. J: Wood. C. F. Woodward, R. Worsham, H. Wyid, R. G. East Cleveland-- Stark, W. E. Elyria-- Kalinsky, A. G. Maynard, J. E. 'Euclid-- Seigel, L. J. Garfield'Heights-- Steffner, E. F. Hamilton--' Thomas, L. G. L. Hudson-- Follett, T. L. Lakewood-- Longcoy, G. B. Norrington, W. L. Schurman, J. A. Weatherby, E. P., Jr. Lima-- Hawisher, H. H. Lorain-- Jackson, W. F. Mariemont-- Crombie, J. Neal. J. P. Middletown-- Byrd, T. Newark-- Waggoner, J. H. Norwood-- Braun, J. J. Oberlin-- Ries, L. S. Sable. E. J. Painesville-- Hobbs, J. C. Plqua-- Bottum, E. W. Lange, R. T. Shaker Heights-- Foley, J. L. Veale, T. South Park-- _ Barney, W. E. Carnahan, J. H. Carroll, W. M. Dolan, R. G. Feldstein, H. Gray, E. W. Holyfield, E. F. Hoppe, A. A. Kidd. C. R. Kroeker, S. P. Lockwood, G. E. Loeffler, F. X. Mideke, J. M. Miller. B. R. Morin. A. R. Rolland, S. L. Spencer, D. Tiller. L. Tulsa-- . . Dean, C. H. Holmes. A. D. Irwin, R. R. Jones, E. ' Meinholtz, H. W. Mumford, W. W. Pauling, R. E. Shoemaker, F. F. * Springfield-- Hauck, E. L. n Noble, J. P. ' Toledo-- ' Baker, H. C. Bergan, J. R ` Jones, S. Mabley, L. C. McKitrick, W. D. Summers, C. G. Terry, M. C. Watkins. .G. B. OREGON Corvallis-- . Willey, E. C. . Gladstone-- Williams, L. G. Medford-- Hoey, J. K. Warren-- Trenner, K. M ultnomah-- Brissenden, C. W. Waverly-- Armbruster, F. T. W. Wilmington-- Portland-- ; Armstrong. C. E.. Banta, G. L. Burton, W, R. Marconett, V. G. Sapp, C. L. Worthington-- Slemmohs. J. D. ... Youngstown-- ' Montgomery, J. R. Xenia-- Lindsay, G. W-., Jr. ` OKLAHOMA . Norman-- - Dawson, E.'FV '* . Oklahoma City-- . . Braniff, P. R.:> . ; Campbell, A..y). y Lrfirruu, c.. c. Clark, A. C. Enders; C. E. Fames, B. W. Finnigan, W. T. Fox. W. K. Freeman, J. A. Gehre. W. . Goebler, E. E. Hanthom, W. Heinkel; C. E. Kolias, W. J. Kroeker. J. D. MacGregor, C. M. McClung, T. H. McDermott, J. P. Mclndoe, J. F. Mead, H. K. Michaels, M. A. Moore, B. W. Morrison, W. B. Munro, D. R., Jr. Murhard, E. A. Murhard, K. R. Neubauer, E. W. Nielsen, H.. B. Ponder, E. A. Richardson. L. S. 85 Taylor. T. E. Turner, E. S. Urban, F. F. Watson. K. W. Weller, A. K. Widmer, W. J. Yates. J. E. Salem-- Cooper, D. E. PANAMA Canal Zone-- Danielson, W. A. PENNSYLVANIA Abington-- Bigelow. E. S. Park. N. W. . Aldan-- ", \ ; Mulcey, P. A;` ; Allentown-- Goundie, J. K. Hersh, F. C. . Kora, C. BL Ambler--. . . McElgin, J. W. Ardmore-- Haynes, C. V.. . Ardsley-- - . Tucker, L. A. Aspinwall-- - - Lewis, K. C. Bala-Cynwyd-- . Whitney, C.-'W.' Beaver Falls-- Zitzman, F. T. Bellevue-- Allen. W. A. . . Kenney, T. W. . Be thlehem--, Murnin, E. A., Jr. Stuart, M. C. Blalr8ville^T- , Mabon, J. E. Boyertown-- Harberger, G. L. V HEATING VENTILATING AIR CONDITIONING CUIDE 1940 Bradford-- Cleveland, C. C. Paterson. F. C., Jr. Ruple. P. E. Charleroi-- Sutherland, F. A. Clearfield-- Gault. G. W. Collcgeville-- Hall. M. S. Drexel HiU-- Matz, G. N. Stokes, A. D. ` Dunbar-;-- Sherwood, L. T. East Pittsburgh-- Penney, G. W. Elizabethtown-- Dibble. S. E. Joyce, H. B. Preece, L. W. Sahlmann. F. L. Glenmoore-- Gant, H. P. Harrisburg-- Eicher, H. C. Geiger, I. H. Hedlund. R- A. Hershey-- Suavely, A.B. Johnstown-- Hunter, L. N. Knowles, F. R.. Novotney, T. A. Kingston-- Macdonald, D. B. Stewart, J. P. Jones, A. Lloyd, E. C. Shorb, W. A. Lansdowne-- James, H. R. Mayer, R. L. Seltzer, P. A Manheim--, Wdtsd. C. B. Wdtxel, P. H. McKeesport-- Dugan, T. M. Middletown-- Locke, R. A. Narberth-- Grant, W. A. Searle, W. J., Jr. New Castle-- Andrews, G. H. New Kensington-- Edwards, J. D. Shearer. W. A., Jr. Newtown-- Lews, T. .. Oakmont-- Liebermann, M. S. Oxford-- Ware. J. H., Ill Penn Valley-- Smith, W. F. Philadelphia-- Arnold, R. S. Bachman, F. Barnard, M. E. Bartlett, C. E. Bates, J. H. Black, E. N.. 3rd Black, H. G. . Blankin, M. F. Bogaty, H. S. - Bornemann, W. A Caldwell, A. C. , Call. J. ' Carney, E. J. Cassell, J. D. Childs. L. A. Cody. H. Cl Culbert, W. P. Dafter, E. H.. D'Ambly, A. E; Davidson, L. C, Davidson, P. L. ` Dietz, C. F.; . Dome, A. G. ' Donovan, W. J. Eastman, C. B. Eckart, J. H.. Elliot, E. . Erickson, H. H: Faltenbacher, H. J. Familetti, A R. ' Galligan, A. B. . Gillett, M. C: Gilman, F. W. Goff, j. a; . Guler, G. D. Hackett, H. B. Hajek, W. J. Hedges. H. B. . Hibbs, F.C; ." : Hildreth, L. W. Hucker, J. Hi. Hunger, R. F. Hutchison, J. E. ' Hynes, L. P. . Ickeringill, J. Jacobsen. K. C. S. Jakoby, A. C. Jardine. W. H.. Jr. Kelble, F. R. Killough, R. E. Kirkbride, J. O. Kohler, J. C. Kriebel, A. E. Ladd, D. Landau, M. Lauer, R. F. Leopold, C. S. Lyon, P. S. . Mack, L. ' Makin, H. T., Jr. Martocello, J. A. Mather, H. H. McCaffray, C. E. McClintock, A., Jr. McCullough, H. G. Mcllvaine, J. H. Mellon, J. T. J. Meloney, E. J. Mensing, F. D. Millham, F. B. Moody, L. E. Morgan, R. C. Munro, G. A. Murdoch, J. P., Jr. Nesbitt, A. J. Nesbitt, J. J. Newcomb. L. B. Nusbaum, L. - Parent, H. M. Pfeiffer. F. F. Plewes, S. E. Powell. G. W.. Jr. Powers. Earle C. Powers, Edgar C. Prewitt, H. B. Pryibil. P. L. Redstone, A. L. Reilly. C. E. Rettew, H. F. Roberts, H. L. Rugart, K. Sabin, E. R. Schneider, C. H. Schulz, E. L. . Shanklin. A. P. Shapiro. C. A. Sheffier, M. Speckman, C. H. Sullivan, C. J. Timmis, P. Touton, R. D. Traugott, M. Tuckerman, G. E. Wagner, E. K. Wegmann, A. Wells, W. F. Wiley, D. C. Wilmot, C. S. Wilson, F. J. Wiltberger, C. F. Woolston, A. H. Pittsburgh-- Allensworth, J. E. Armour, E. G. Beighel, H. A. Blackmore, G. C. Borton, A. R. Brauer, R. Braun, C. R-, Jr. Bushnell, C. D. Carr, M. L. Caskey, L. H., Jr. Collins. J. F. S., Jr. Comstock, G. M. Cost. G. W. . Cox, S. F. Dickinson. R. P., Jr. Dickson, R. W., Jr. 86 Dorfan, M. I. Edwards, P. A. Ellis, G. P. Ferderber, M. B. Gallagher, F. H. Grabman/H. B. Greiner, G. E.p Jr. Griest, K. Hampie, H. J. Hathaway, C. B. . Hazlett, T. L. Hebley, H. F. J. Hecht, F. H. Heilman, R. H. Houghten, F. C. Humphreys, C. M. Hyde, E. H. Jones, L. K. Kirkendall, H. J. Landes. B. D. Lifshitz, H. ` Long, E. J. ' . Loucks, D. W. . Lowe. W. ` Maehling, L. S. Mahon, F. B. - Marshall, A. W. ! McCullough, J. L. McGonagle, A. McIntosh, F. C/* McLean, J. E. Miller, R. A. Moore, H. L. ' Mueller, J., E. Nass, A. F. NichoJls, P. Park, H.* E. Parks, C. E. Peacock, G. S. ` Proie, J. Reed, I. G. - . Reed, V. A., Jr. Reed. W. H., Ill . Reilly, B. B. Riesmeyer, E. H., Jr. Rockwell, T. F.. ' Rose, H. J. . Rosenberg, I. Scanlon, E. L. Schmieler. J. B. Selig, E. T., Jr. ' ; Sgambati. A P..- Shore, D. -- - Slutsky, D. J. Small, B. R. ' Smith, R. L. .. - Smyers, E. C. Speller, F. N. < Stanger, R. B. :' SteggaU, H. B. Stevensoh, W. W; Strauch, P. C. Tennant, R. J. J. ,, Tower, E. S. Tumpane, J. -P.. Jr: Waters, G. G. ' Weddell, G. O. Zangrilli, A; J. Pottsville-- Marty, E. O. Primes--: Johnson, A. J. Reading-- . Luck, A. W: . Ridley Park-- Mawby, P. ROLL OF MEMBERSHIP Rochester-- Pugh; D. C. Scranton-- Mahon, B. B. Sewickley-- Lore. H. E. Springdale-- Lynn, F. E. Springfield-- Grossman, H. E. State College-- Queer, E. R. Stroudsburg-- Kiefer, E. J., Jr. Swarthmore-- Hobbs, W. S. ' Krayenhof, H. G. Robinson, A. S. Thom, G. B: Tarentum-- * Orr, L. Uniontown-- Marks, A. A'. Upper Darby-- Bertrand, G. F. Kipe, J. M. Macrow, L. McClain, C. H. Morehouse, J. S. Hertzler, J. R. Kartorie, V. T. Mirabile, J. J. Muhleman, R. F. Nicoll, S. F. Walsh, E. R., Jr. Zieber, W. E. PHILLIPINE ISLANDS Manila-- Hausman, L. M. Macrae, R. B. RHODE ISLAND Cranston-- Fenner, E. M. Pawtucket-- Kramer, C. Providence-- Arden, I. L. . Blanding, R. L. Coleman, J. B. Gibbs, E. W. Hartwell, J. C. Lee. R. T. McCarthy, J. J. McLaughlin, J. D. Moulder, A. W. SOUTH CAROLINA Villa Nova-- Barr*, G. W. Washington1-- Frazier, J. E. Wilkinsburg-- Biber, H. A. Campbell, T. F. Good, C. S. Graham, J. B. Williamsport-- Axeman, J. E. Wormleysburg-- * Miller, T. G. Charleston-- Bailey, F. A., Jr. Clemson College-vShenk. D. H. ' Columbia-- Hartin, W. R., Jr. Kerr. W. E. Mercer, C. F. Reamer, W. S., Jr. Greenville-- . Waldrep, J. E. SOUTH DAKOTA Wyncote-- Buck, L. York-- Aughenbaugh, H. E. Barnum, W. E., Jr. Dull. E. J. Lead-- Pullen,-R. R. Sioux Falls-- Monick, F. R. TENNESSEE Chattanooga-- Patterson, J. D. Donelson-- Wilson, V. H. Elizabethton-- Torok. E. Knoxville-- Cross. F. G. Oakley, L. W. Memphis-- D'lmor, E. J. Flinn, G. S. Hoshall, R. H. Nashville-- Armistead, W. C. Baker, W. C. Brown, F. Campbell, A. Q., Jr. Campbell, G. S. Crane, R. S. TEXAS . Amarillo-- Burnett, E. S. Houska, A. D. Towne, C. O. Austin-- - Degler, H. E. Gossett, A. L. College Station-- Badgett, W. H..... Cook, A. L. Giesecke, F. E. Hines, G. M. Hopper, J. S. Long, W. E. Smith, E. G. Dallas-- Anspacher, T. H. Berry, R. U. Bishop, J. A. Blum, H.P Jr. Bock, 1. I. Brown, M. L. Brown. M. W. Cheatwood, W. H. Cox, V. G. Farrow, E. E. Gardner, C. R. Gilbert. L. S. Green, S. H. Jelinek, F. R. Kribs, C. L., Jr. Landauer, L. L. Linskie, G. A. Lyford. R. G. Martyn, H. J. McClanahan, L. C. Mehl, O. H. Moler, W. H. Moore, B. J., Jr. Perkins. R. C. Pines, S. Renouf, E. P. Rodgers, F. A. Rogers, R. C. Taylor, R. B. Ullrich, A. B., Jr. Zumwalt. R. Falfurrias-- Jenson, J. S. Fort Worth-- Cawby, E. L. Harris, A. M. MacEachin, G. C. McKinley, C. B. Skinner, H. W. Sprekelmeyer, J. M. Werner, R. K. Galveston-- Ruemmele, A. M. Houston-- Banowsky, A. B. Barnes, A. F. Beaird, B. J. Chase, A. M., Jr. Chrone, R. E. Closner, J. J. Constant, E. S. Cooper, D. S. Dillender, E. A. Drescher, F. E. Earl, W. Keeland, B. W. Kiesling, J. A. Koch. A. C. Kurtz, R. W.. Maves, G. D. McKinney, C. A. Mitchell, J. Morrow, J. DeW. Olson, G. E. Pettit, E. N., Jr. Rollosson, J. A. Rowe, I. E. Salinger, R. J. ` Spencer, R. M. Taylor, R. F. Walsh, J. A. Witmer, C. N. Kingsville-- Richtmann, W. M. Lubbock-- Ainsworth, S. E. Port Arthur-- Shaw, C. G. San Antonio-- Barnes. R. W. Diver, M. L. Ebert, W. A. Kotzebue, R. W. Pawkett, L. S. Rhine, G. R. Rummel. A. J. Waco-- Benham, F. C., Jr. HEATING VENTILATING AIR CONDITIONING GUIDE 1940 UTAH Salt Lake City-- Richardson, H. G. Young, J. T-, Jr. VERMONT Burlington-- Lanou, J. E. Raine, J. J. North Ferrisburg-- Breckenridge, L. P. VIRGINIA Alexandria-- Goergens, A. G. Skagerberg, R. Arlington-- Bozeman, R. Ferrarihi, J. Grimes, F. M. Marshall, W. D. Nye, L. B.. Jr. Welsh, H. A. Blacksburg-- . Johnston, R. M. Front Royal-- Hartsook, G. S., Jr. Lynchburg-- Doering, F. L. Franklin, S. H., Jr. Mechanicsvilli Odum, R. A. Norfolk-- Capps. E. L. . Huybert, L. E.. Jr. Nowitzky, H. S. Thomas, R. C. Portsmouth-- Stubbs, W. C. Richmond-- Campbell, F. B. Carte, W. E. Hinnant, C. H., Jr. Johnston, J. A. Peebles, J. K,, Jr. Pelouze, H. L., II Schulz, H. I. Roanoke-- Bailey, A. E., Jr. Bernert, L. A. Nininger, C. H. WASHINGTON Largent-- ' Donnelly, J. A. . Bremerton-- Bysom, L. L. Kent-- Boyker, R. O. Wheeling-- Hitt. J. C. WISCONSIN Port Orchard-- Pratt. F. J. Seattle-- Beggs, W. E. Bouillon, L. Clausen, A. H. Cox. W. W. Davis,-R. J. Eastwood, E. O. Granston, R. O. Griffith, H. T. Hauan, M. J. Mallis, W. May, C. W. Morse. R. D. Musgrave, M. N. O'Connell, P. M. Peterson, S. D. Pollard, A. L. Sparks, J. D. Twist, C. F. Veltman, B. M. Ward, J. J. Watt, R. D. Weber, E. L. Wesley, R. O. Zokelt, C. G. Spokane-- Brown, S. D. Russell, W. B. Tacoma-- Chase, R. E. Foote, E. E. Norby. K. H. Spofforth, W. Vancouver-- Alben, E. Yakima-- Leichnitz, R.- W.McCune. B. V. WEST VIRGINIA Charleston-- Rosenblatt, A. M. Rothmann, S. C. Saginor, S. V. Shankiin, J. A. Fairmont-- Tonry, R. C. Wright. C. E. Huntington-- Johnson, L. O. Appleton-- Eiseie, D. E. Clintonville-- Quail, C. O. Eau Claire-- Grosvold. F. E. Elm Grove-- Winkler, R. A. Kohler-- Hvosief, F. W. Kohler. W. J.. Jr. La Crosse-- Anderegg, R. H. Miller. M. W. Pellmounter, T. V. Rowe, W. A. Shafer. W. P., Jr. Thomas, N. A. Trane, R. N. Madison-- Bledsoe, R. P. Dean, C. L. Feirn, W. H. Hall. G. Kliefoth, M. H. Larson. G. L. Nelson, D. W. Seymour, J. E. White. J. C. Milwaukee-- . Alfery. H. F. Allan, W. Banks, J. B. Becker, C. S. Boden, W. F. Bowers, A. F. Brown, W. H. Buller, C. R. Carroll, A. F. Cutler, J. A. Davis, K. T. Ellis, H. W. Frentzel, H. C. Gerstenberger, E. J. Goldsmith, F. W. Gregg, S. H. > Griewisch, A. H. Haerle, R. A. Hamacher, K. F. Hanley. E. V. Haupt, H. F. . Haus, I. J. Hays, C. A. Hessler, L. W. Hoffmann, A. 88 Hughey, T. M. Jackson. C.. H. Jones, E. A. ' Jung, J. S. Ketter, J. W. * * Koch, R. G. Kluge. B. M. Krenz, A. S. Lingen, R. A. Mack. E. H. McKee, J. W. Miller, C. W. Miller, L. B. Mueller, H. P. Mullen. T. J., Jr. Noll. W. F. Page. H. W. Podolske, A. R. . Randolph, C. H. Reinke, L. F. Rice, C. J. Rossiter, I. J. Schmid. J. U. Schreiber, H. W. Shawlin, W. C. Shodron, J. G. Spence, M. R- Stevens, W. H. Swisher, S. G.. Jr. Szekely, E- ' Thom, A. J. Trostel, O. A. Tutsch, R. J. Volk, J. H. Weil, F. H. E. Weimer, F. G. Werner, P. H. Neenah-- Angermeyer, A. H. Eiss, R. M. . Stiegler. A. J. Racine-- Dixon, A. G. South Milwaukee-- uweneel, W. A. Wauwatosa-- Leitgabel. K. A. West Allis-- Erickson, M. E. DOMINION OF CANADA Brandon, Man.-- Yates, J. E. Yates. J. E.. Jr. Calgary, Alta.-- Vissac, G. A. Edmonton, Alta.-- Mould. D. E. FIin Flon, Man.-- Foster. P. H. ` ROLL OF MEMBERSHIP Freeman, Ont.-- Goodram. W. E. Galt, Ont.-- Sheldon. W. D. Halifax, Npva Scotia Meagher, A. T. Hamilton, Ont.-- Barnes, H. Dickenson, M. E. Moffat, O. G. Hampstead, P. Q.-- Montgomery, E. G. Islington, Ont.-- Wilson, G. T. Kingston, Ont.-- Arkley, L. M. Kirkland Lake, Ont. Calver, R. W. Libby. R. S. Kitchener, Ont.-- Beavers. G. R. Pollock, C. A. Lindsay, Ont.-- McCrae. G. W. London, Ont.-- O'Flaherty, J. G. Rogers, T. L. C. Johnson, C. W. Lafontaine, E. A. LaMontagne, A. F. LaRue, J. A. D. Linton, J. P. Madely. F. J. Martin, L. Martin, R. Milne. A. H. Morris, J. A. Murray, H. G. S. Nathan, P. V. Nickle, A. J. Noyes, R. R. Osborne, G. H. Peart, A. M. Perras, G. E. Phipps, F. G. Plant, E. B. Pratt, J. C. Robertson, J. A. M. Roche, I. F. Ross. J. D. Sampson, E. T. Shaw, J. A. Spark, W. Standring, R. A. Ste Marie, G. P. Timmins, W. W. Tolhuret, G. C. Twizell, E. W. Vollmann, C. W. Walford, L. C. A. Watts, A. E. Wiggs, G. L. Wilkinson, A. Wilson, A. Wormley, R. F. Worthington, T. H. Moosomin, Sask.--: Barton, E. H. Noranda, P. Q.-- MacLean, H. A. Montreal. P. Q.-- ' Allaire, L. Armstrong, W. J. Ballantyne, G. L. Barnsley, F. R. Baxter. W. E. Berridge, W. W.. Boland, R. O. Chenevert, J. G. Colle, S. S. Darling, A. B. Dufault, F. H. Dykes, J. B. Elliot. G. B. Emerson, J. J. Flanagan, J. B. Forrester, N. J. Freeman, E. M. Friedman, F. J. Gameau, L. Hamlet, A. - Hamlet. T. F. Hughes. H. R. Hughes, W. U. Oakville, Ont.-- , Stott, F. W. 'Ottawa*. Ont.-- Allen, A. W. Colclough, O. T. Gray, G. A. McGrail. T. E. Pennock, W. B. Outremont, P. Q.-- Gittleson. H. Keith, J. P. Preston, Ont.-- Everest, R. H. Wood, A. W. Quebec, P. Q.-- LaRocque, P. E. Paquel, J. M Roy, L. Sackvlile, N. B.-- Johns, C. F. Rand, F. R. St. Lambert, P. Q.-- Lefebvre, E. J. Sherbrooke, P. Q.-- Archambault, J. A. Three Rivers, P. Q.-- Germain, O. Timmins, Ont.-- Smith, R. J. Toronto, Ont.-- Abbott, T. J. Alexander, S. W. Allcut. E. A. AUsop, R. P. Angus, H. H. Anthes, L. Arrowsmith, J. O. Baker, G. R. Baker, L. P. Bishop, J. W. Blackball. W. R. Blizzard, B. C. Bowerman, E. L. Brittain, A., Jr. Carter, A. W. Chambers, F. W. Church, H. J. Clifton, J. A. Cole. G. E. Davis, E. J. Daynes, J. H. Dickey, A. J. Dickson, G. P. Dion, A. M. Dowler, E. A. Duncan, W. A. Eaton. W. G. M. EUis, F. E. Ewens, F. G. Fear, S. L. Fitzsimons, J. P. Foley; J. J. Forrester, C. M. Fox, E. Fox, J. H. Gauley, E. R. Givin, A. W. Gordon. C. W. Gordon, W. D. Gumey, E. H. Gurney, E. R. Harrington, C. Henion, H. D. Hill. H. G. Hills. A. H. Hopper, G. H. Hughes, L. K. Jenney, H. B. Jennings, S. A. Jones, A. T. Kelly, W. C. Lawlor, J. J. Ledgett, F. D. Leitch, A. S. Lock. R. H. MacDonald, D. J. Marriner, J. M. S. Mathison, R. S. Maxwell, R. S. McKerlie, J. Moore, F. C. Moore, H. S. Morgan, A. S. Nearingburg, A. Oke. W. C. O'Neill. J. Paul. D. I. Philip, W. Playfair, G. A. Price, D. ORitchie, A. G. Roth. H. R. Shears, M. W. Smith. W. H. Spall, E. G. Stencel, R. A. . Sturdy, O. C. Tasker, C. Thomas, M. F. Thomsen, N. B. Treleaven, H. M. Waldon, C. D. Wardell, A. Wilier, M. D. Woollard, M. S. World, H. P. Vancouver, B. C.-- Hale. F. J. Johnston, R. E. Leek, C. W. Leek. W. Turland, C. H. Victoria, B. C.-- Sheret. A. Westmount. P. 0-- Cotford. J. Winnipeg, Man.-- Argue. E.. J. Charles, P. L. Davis, G. C. Eade, H. R. Glass. W. Jones, B. G. Kent. R. L. Kipp, T. McDonald, I. Michie, D. F. Miller, E. R. Munn, E. F. Price, E. H. / Steele, J. B. Summers, E. T. Thompson, F. Worton, W. Woodstock, Ont.-- - Karges, A. W" HEATING VENTILATING AIR CONDITIONING GUIDE 1940 AUSTRALIA Melbourne-- Atherton. A. E. Bell. S. R. Davies. R. H. Ross, R.. Sydney-- Davey, G. I. Henderson. A. S. Hunt. N. P. Moloney, R. R. Picot, J. W. Robinson, J. A. Roseby, T. A. Sands, C. C. BELGIUM Brussels-- Lebrun. P. BERMUDA Hamilton--- Kitchen, W. H. J. BRAZIL Rio de Janeiro-- Botelho. N. J. Darby. M. H. DeSales, M,, Jr. DesReis, J. F.- CHILE Santiago-- Demeter, J. CHINA Shanghai-- Bradford, G. G. Chen. S. T. Doughty. C. J. . Gange, F. B. Hart-Baker, H. W. Hutchinson, F. A. Kwan, I. K. Loh, N. S. Loo, P. Y. Morrison, C. B. Muckle, j. Waung, T. F. Wong. W. S. B. CUBA Havana-- Colmenares, C. V. Cowell, R. J. DENMARK Surrey-- Casperd. H. W. H. Reinbeck-Hamburg-- Brandi, O. H. Copenhagen-- Reck. W. E; Schulein, E. H. EGYPT Alexandria-- Tallianos, P. C. Cairo-- Ezz El Din, K. Henszey. W. P. Tahry, M. E. Trowbridge-- . Haden, W. N. Warwickshire-- Mann. W. N. Westminster-- ' Russell, J. N. Wolverhampton--. Tyson, W. H. FRANCE Stuttgart-- Klein, A. INDIA Calcutta-- , Ghose. K. N. Ghosh, B. B. . Rachal, J. M. . Stirling, W. N. Stromgren, S. G. IRELAND ENGLAND Birmingham-- Richardson, R. D. Kent-- Figgis, T. G. Lipscombe, H. W. J. Lancaster-- Bartley, H. E. Leeds-- Jennins, H. H. Liverpool-- Thomas, A. E. London-- .. Bailey, W. M. Benham, C. S. K. Bird, G. L. H. Butt, R. E. W. Chester, T. Daniel, W. E. Faber, O. Greenland, S. F. Haden G. N. . Heard, J. A.'E. Herring, E. Jackson, G. R. . Kraminsky, V. Nobbs, W. W. Pryke, J. K. M. Swain, W. L. Symonds, E. S. Troup, J. D. Wilson, E. D. Boulogne-- . Waudby, W. Lille-- Neu, H. J. E. Lyon-- Goenaga, R. Paris-- Bodmer, E. Modiano, R. Nessi, A. Schmutz, J. Sucy en BrieBeaunienne, Vanves-- Ghilardi, F. FRENCH INDO CHINA Hanoi-- Cox. P. E. FRENCH NORTH AFRICA Cork-- Barry, P. 1.5 Dublin-- - . Leonard, L. C.` G. ITALY Florence-- Scotti, F. D. Milan--r Dell'Orto, L. Gini, A. Hauss, C. F. Marzorati. G. Parrilli, R. . Torino-- Baldi, G. JAPAN Osaka-- . Fukui, K, Tokyo-- ' Kitaura, S. Saito, S.. ; 'Sekido, K.' Manchester-- Pougher, E. W. Webb, J. W. Yates, W. Middlesex-- Case, W. G. Fraser, J. J; MacLachlan, V. D. Nottingham-- Norfolk, L. W. St. Albans-- Carter, D. Algiers-- Macherel, F, GERMANY BerlinCharlottenburg-- Brust, O. Berlin-Wilmersdorf-- Schmidt, E. G, 90 MANCHUKUO Hslnking-- Kawase, S. MEXICO Mexico, D. F.-- Gilfrin, G. F. Huber, E. . Martinez, J.'J. ROLL OF MEMBERSHIP NETHERLAND WEST INDIES San Nicholas-- Silvera, A. Dunedin-- Davies. G. W. NORWAY NETHERLANDS Amsterdam-- ter Weeme, A. Arnhem-- . Tanger, O. C. F. The Hague-- DeWilde, M. P. NEW ZEALAND Auckland-- Manning, C. E. Christchurch-- Taylor, E. M. . Vale, H. A. L. Oslo-- Tjersland, A. Stabekk-- a Alfsen, IjJ. PALBSTINE Tel Aviv-- . Petigrow, B. N. ROUMANIA Bucharest-- Wasser, M. SOUTH AFRICA SWEDEN Capetown-- Ehiera, J. Durban-- Gordon, H. H. W. Kothe, F. H. Johannesburg-- Boxall. F. Daitsh, A. Overton, S. H. Rabe, A. E. von Christierson, C. A. Sheepmoor-- Steenkamp, W. ' SPAIN Lidingo-- Rosell. A. F. Nockeby-- Erikson, H. A. Stockholm-- Eklund, K. G. Gille, H. Ostrom, E. W. Theorell, A. T. TheoreU. H. G. T. TURKEY Madrid-- Alfageme, B. .Istanbul-- Karakash, T. J. Veglery, A. STRAITS SETTLEMENTS VENEZUELA Singapore-- Faxon,, H. C. . Hill, C. F. Caracas-- Bias, R. J. Westendarp, F. G. 91 PAST OFFICERS American Society of Heating and Ventilating Engineers 1894 President:.__________________ --___ Edward P. Bates 1st Vice-PresidentWm. M. Mackay Snd Vice-President______________ -.Wiltsie F. Wolfe Srd Vice-PresidentChas. S. Onderdonk Treasurer___________Judson A. Goodrich Secretary____ -- ................. ........---*-L. H. Hart 1898 President________ _____________ ____Wiltsie F. Wolfe 1st Vice-President.J. H. Kinealy Snd Vice-President___________ _____-A- E. Kenrick Srd Vice-President..... ......... ............--John A. Fish Treasurer-,Judson A. Goodrich Secretary.1.1Stewart A. Jellett Board of Managers . Chairman, Fred P. Smith Henry Adams A. A. Cary Hugh J. Barron James A. Harding Edward P. Bates. Pres. L. H. Hart. Secy. Council Chairman, R. C. Carpenter Albert A. Cryer Chas. W. Newton F. W. Foster Ulysses G. Scollay. Secy. . 1895 President________________________ Stewart A. Jellett 1st Vice-PresidentWm. M. Mackay end Vice-President_Chas. S. Onderdonk Srd Vice-President---D. M. Quay Trsnxttrer .................. .......... Judson A. Goodrich Secretary........................... -................... ....... L. H. Hart Board of Managers Chairman, James A. Harding Geo. B. Cobb Ulysses G..Scollay Wm. McMannis B. F. Stangland Stewart A. Jellett. Pres. L. H. Hart. Secy. Council Chairman, R. C. Carpenter Henry Adams T. J. Waters Edward P. Bates Albert A. Cryer. Secy. 1896 President______ ___ ________________ R. C. Carpenter ' 1st Vice-President.............................. ....... -D. M. Quay end Vice-PrestdentEdward P. Bates Srd Vice-PresidentF. W. Foster Treasurer_______ _Judson A. Goodrich Secretary......................... ........................--L. H. Hart Board of Managers Chairman, Wm. M. Mackay Thomas Barwick ' A. C. Mott John A. Connolly Francis A. Williams Wiltsie F. Wolfe. Pres. Stewart A. Jellett. Secy. Council Chairman, R. C. Carpenter Henry Adams W. S. Hadaway. Jr. Albert A. Cryer Wm. McMannis Wiltsie F. Wolfe. Pres. Stewart A. Jellett. Secy. 1899 President__________________________ _..Henry Adams 1st Vice-President__________ ---------------- D. M. Quay end Vice-PresidentA. E. Kenrick Srd Vice-President__ ___________Francis A. Williams Treasurer____________ _____ _ , Judson A. Goodrich Secretary___;-:________ Wm. M. Mackay Board of Managers Chairman, Stewart A. Jellett B. H. Carpenter Wen. Kent A. A. Cary Wiltsie F. Wolfe Henry Adams. Pres. Wm. M. Mackay. Secy. Council Chairman, R. C. Carpenter John Gormly Wm. McMannis W. S. Hadaway. Jr. B. F. Stangland Henry Adams. Pres. Wm. M. Mackay. Secy. Board of Managers . Chairman. Wm. M. Mackay Hugh J. Barron Stewart A. Jellett W. S. Hadaway. Jr. Wiltsie F. Wolfe R. C. Carpenter. Pres. L. H. Hart. Secy. Council Chairman, A. A.1 Cary Albert A. Cryer B. F. Stangland Wm. McMannis J. J. Blackmore, Secy. 1897 President.Wm. M. Mackay 1st Vice-President..---.................... ........ H. D. Crane end Vice-PresidentHenry Adams Srd Vice-President........... .......------------ A. E. Kenrick Treasurer.Judson A. Goodrich Secretary_________ ____ _____________H. M. Swetland Board of Managers Chairman, R. C. Carpenter Edward P. Bates Stewart A. Jellett W. S. Hadaway. Jr. Wiltsie F. Wolfe Wm. M. Mackay. Pres. H. M. Swetland. Secy. Council Chairman. Albert A. Cryer John A. Fish James Mackay Wm. McMannis B. F. Stangland President--------------1st Vice-Presidentend Vice-President. -Treasurer Secretary__________ 1900 _______JD. M. Quay . -A. E. Kenrick .Francis A. Williams Judson A. Goodrich ___Wm. M. Mackay Board of Governors Chairman, D. M. Quay Wm. Kent. Vice-Chm. D. M. Nesbit R. C. Carpenter C. B. J. Snyder John Gormly Wm. M. Mackay. Secy. President______ __ 1st Vice-President_ $nd Vice-President. Treasurer-------------Secretary............. -- 1901 ........... ............J. H. Kinealy ____ ________A. E. Kenrick Andrew Harvey '.Judson A. Goodrich _________ Wm. M. Mackay Board of Governors Chairman, J. H. Kinealy Wm. Kent, Vice-Chm. John Gormly R. C. Carpenter C. B.J. Snyder R. P. Bolton Wm. M. Mackay. Secy. 92 ROLL'OF MEMBERSHIP President -________ 1st Vice-President-- Snd Vice-President_ Treasurer.._________ Secretary^______ ....A. E. Kenrick -Andrew Harvey --Robert C. Clarkson -Judson A. Goodrich ___ Wm. M. Mackay Board of Governors Chairman, A. E. Kenrick John Gormly, Vice-Chm. J. H. Kinealy R. C. Carpenter C. B. J. Snyder Wm. Kent Wm. M. Mackay, Secy. President__________ 1st Vice-Presidents Snd Vice-Presidents TreasurerSecretary.... ..C. B. J. Snyder __James Mackay ...Wm. G. Snow -------- Ulysses G. Scollay .........--Wm. M. Mackay Board of Governors Chairman. C. B. J. Snyder James Mackay, Vice-Chm. Frank K. Chew R. E. Atkinson A. B. Franklin R. C. Carpenter Wm. G. Snow Edmund F. Capron Wm. M. Mackay, Secy. 1903 President________________________ _____ H. D. Crane 1st Vice-President-____________________ Wm. Kent Snd Vice-PresidentR. p. Bolton Treasurer----------------- ----------------Judson A. Goodrich Secretary.---------------------------------- Wm. M. Mackay Board of Governors Chairman, H. D. Crane C. B. J. Snyder. Vice-Chm. A. E. Kenrick R. C. Carpenter Geo. Mehring John Gormly Wm. M. Mackay, Secy. 1st Vice-Presidentm Snd Vice-President_ Treasurer__________ Secretary.___ -........... ____ James Mackay ___Jas. D. Hoffman ----B. F. Stangland ..Ulysses G. Scollay __Wm. M. Mackay Board of Governors Chairman, James Mackay Jas. D. Hoffman, Vice-Chm. John F. Hale n. F. Stangland August Kehm R. C. Carpenter C. B. J. Snyder Frank K. Chew Wm. M. Mackay. Secy. 1st Vice-Presidents Snd Vice-President____ Treasurer______________ Secretary_______________ ..Andrew Harvey John Gormly ----- Robert C. Clarkson ------- Ulysses G. Scollay ___ 1__Wm. M. Mackay Board of Governors Chairman-, Andrew Harvey John Gormly H. D. Crane Robert C. Clarkson A. E. Kenrick J. J. Blackmore C. B. J. Snyder R. C. Carpenter Wm. M. Mackay, Secy. PraUUntsss-. 1st Vice-President_________ Snd Vice-President______ ._ Treasurer_________________ Secretary--......... -------Wm. G. Snow _____ .August Kehm --------B. S. Harrison ..Ulysses G. Scollay __Wm. M. Mackay Board of Governors Chairman, Wm. G. Snow August Kehm, Vice-Chm, Samuel R. Lewis John R. Allen James Mackay R. C. Carpenter B. F. Stangland B. S. Harrison Wm. M. Mackay, Secy. President- . 1st Vice-Presidents Snd Vice-Presidents. Treasurers^________ Secretary___________ 1905 --Wm. Kent _______R. P. Bolton ------C. B. J. Snyder -Ulysses G. Scollay __Wm. M. Mackay . Board of Governors . Chairman, Wm. Kent * R. P. Bolton James Mackay C. B. J. Snyder B. F. Stangland ' B. H. Carpenter J. C. F. Trachsel A. B. Franklin Wm. M. Mackay, Secy. Presidents 1st Vice-President___ Snd Vice-Presidents. Treasurer^._________ Secretary -Jas. D. Hoffman ____ :R. P. Bolton .Samuel R. Lewis -Ulysses G. Scollay __Wm. M. Mackay Board of Governors Chairman, Jas. D. Hoffman ' R. P. Bolton, Vice-Chm. John F. Hale Geo. W. Barr Samuel R. Lewis R. C. Carpenter James Mackay Judson-A. Goodrich Wm. M. Mackay, Secy. 1906 1st Vice-President___ Snd Vice-President___ Treasurer____________ Secretary_____________ ........... John Gormly ------C. B. J. Snyder _______T. j. Waters -Ulysses G. Scollay __Wm. M. Mackay President____ __ __ 1st Vice-President_. Snd Vice-President_ Treasurers Secretary................... 1911 ,,R. P. Bolton -John R. Allen .......-A. B. Franklin -Ulysses G. Scollay ___ Wm. W. Macon Board of Governors Chairman, John Gormly C. B. J. Snyder, Vice-Chm. James Mackay R. C. Carpenter B. F. Stangland Frank K. Chew T. J. Waters A. B. Franklin Wm; M. Mackay, Secy. Board of Governors Chairman, R. P. Bolton John R. Allen, Vice-Chm. A. B. Franklin John T. Bradley ' Jas. D. Hoffman R. C. Carpenter . August Kehm James H. Davis Wm. W. Macon, Secy. 93 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 President_______....,, 1st Vice-President End Vice-Presidents Treasurer__________ Secretary ______ John R. Alien ______;..John F. Hale .Edmund F. Capron --James A. Donnelly ____ Wm. W. Macon Board of Governors Chairman, John R. Allen John F. Hale, Vice-Chm. Dwight D. Kimball ' Edmund F. Capron Samuel R Lewis R. P. Bolton Wm. M. Maclcay Jas. D. Hoffman Wm. W. Macon. Secy. President__________ 1st Vice-President__ Snd Vice-Presidents Treasurer___ ___ ___ Secretary___________ 1913 --John F. Hale A. B. Franklin .Edmund F. Capron _James A. Donnelly .____ Edwin A. Scott Beard of Governors Chairman, John F. Hale A. B. Franklin, Vice-Chm. James A. Donnelly John R. Allen Dwight D. Kimball Edmund F. Capron Wm. W. Macon R. P. Bolton James M. Stannard Frank T. Chapman Theodore Weinshank Ralph Collamore Edwin A. Scott. Secy. President______ ---- 1st Vice-President__ Snd Vice-President-- Treasurer__________ Secretary.................... - _____J. Irvine Lyle .Arthur K. Ohmes _____ Fred R. Still ___Homer Addams ___ Casin W. Obert Council Chairman, J. Irvine Lyle A. K. Ohmes. Vice-Chm. Harry M. Hart Homer Addams E. Vernon Hill Davis S. Boyden James M. Stannard Bert C. Davis Fred R. Still Milton W. Franklin Walter S. Timmis Charles A. Fuller Casin W. Obert, Secy. 1st Vice-President__ Snd Vice-Presidents. Treasurer___ _____ Secretary___________ 1918 ______ Fred R. Stiff .Walter S. Timmis ____ E. Vernon Hill ___ Homer Addams ___ Casin W. Obert Council Chairman, Fred R. Still W. S. Timmis, Vice-Chm. J. Irvine Lyle Homer Addams E. Vernon Hill William H. Driscoll Frank G. Phegley Howard H. Fielding Fred. W. Powers H. P. Gant Champlain L. Riley C. W. Kimball Casin W. Obert, Secy. 1914 President.. 1st Vice-President_____ Snd Vice-President------Treasurer....--................ Secretary_________ .1-- ;_Samuel R. Lewis --Edmund F. Capron .Dwight D. Kimball --James A. Donnelly _____J. J. Blackmore . Council Chairman, Samuel R. Lewis R. F. Capron. Vice-Chm. John F. Hale Dwight D. Kimball' ' Harry M. Hart John R. Allen Frank G. McCann Frank T. Chapman Wm. W. Macon Frank I. Cooper ` James M. Stannard James A. Donnelly J. J. Blackmore. Secy. 1st Vice-Presidents. Snd Vice-President_ Treasurer's.;______ Secretary 1915 .Dwight D. Kimball _____ Harry M. Hart --Frank T. Chapman _____ Homer Addams __ "-'.J. J. Blackmore Council Chairman. Dwight D. Kimball Harry M. Hart, Vice-Chm. Samuel R. Lewis Homer Addams . Frank G. McCann Frank T. Chapman J. T. J. Mellon Frank I. Cooper Henry C. Meyer, Jr. E. Vernon HiU Arthur K. Ohmes . Wm. M. Kingsbury J. J. Blackmore, Secy. 1919 _ ................. . ..Walter S. Timmis 1st Vice-President___________________ E. Vernon Hill Snd Vice-PresidentMilton W. Franklin Treasurer! __________________ IHomer Addams Secretary!___________________________Casin W. Obert Council Chairman, Walter S. Timmis E. Vernon Hill, Vice-Chm. Frank G. Phegley Homer Addams Fred. W. Powers Howard H. Fielding Robt. W. Pryor, Jr. Milton W. Franklin Champlain L. Riley Harry E. Gerrish . Fred R. Still George B. Nichols Casin W. Obert, Secy. President___________ 1st Vice-President__ Snd Vice-President-- Treasurer_____ __ _ Secretary___________ _ 19.20 ______ E. Vernon Hill .Champlain L. Riley --____ Jay R. McColl . Homer Addams --___Casin W. Obert Council Chairman, E. Vernon HiU C. L. Riley, Vice-Chm. Jay R. MCC9II Homer Addams George B.' Nichols Jos. A. Cutler Robt. W. Pryor. Jr. Wm. H. Driscoll W. S. Timmis A. C. Edgar Perry West Alfred Kellogg Casin W. Obert, Secy President_____________ 1st Vice-President____ Snd Vice-President___ Treasurer,,,--------------- -------- Secretary_____________ .Harry M. Hart .Frank T. Chapman --Arthur K. Ohmes _____Homer Addams _____ Casin W. Obert Council Chairman, Harry M. Hart F. T. Chapman, Vice-Chm. Dwight D. Kimball Homer Addams Henry C. Meyer, Jr. Charles R. Bishop Arthur K. Ohmes Frank I. Cooper Fred R. Still Milton W. Franklin Walter S. Timmis E. Vernon Hill Casin W. Obert, Secy. President____ __ 1st Vice-President___ Snd Vice-President___ Treasurer.___________ Secretary____________ 1921 .Champlain L. Riley _____ Jay R. McColl ....... .......... H. P. Gant _____ Homer Addams _____ Casin W. Obert * Council Chairman, Champlain L. Riley Jay R. McColl. Vice-Chm. E. S. Hallett Homer Addams . E. Vernon Hill - Jos. A. Cutler Alfred Kellogg Samuel E. Dibble E. E. McNair Wm. H. Driscoll Perry West H. P. Gant Casin W. Obert, Secy. 94 ROLL OF MEMBERSHIP President___ _______ 1st Vice-President__ Snd Vice-President. Treasurer__________ Secretary____ ______ ____Jay R. McColl _______ H. P. Gant .Samuel E. Dibble ___Homer Addams ___Casin W. Obert Council ,,^_ Chairman, Jay R. McColl H. P. Gant, Vice-Chm. L. A. Harding Homer Addams E. E. McNair Jos. A. Cutler H. J. Meyer Samuel E. Dibble C. L. Riley Wm. H. Driscoll Perry West E. S. Hallett ' Casin W. Obert, Secy. President............... .. 1st Vice-President.n Snd Vice-President-- Treasurer-- Secretary.__________ ---F. Paul Anderson _______A. C. Willard ____ Thornton Lewis _____ W. E. Gillhara -__A. V. Hutchinson Council Chairman, F. Paul Anderson A. C. Willard, Vice-Chm. John Howatt H. H. Angus W. T. Jones W. H. Carrier J. J. Kissick W. H. Driscoll E. B. Langenberg Roswell Famham Thornton Lewis H. H. Fielding J. F. Me Intire W. E. Gillham H. Lee Moore C. V. Haynes F. B. Rowley ' President...___ __________ 1st Vice-President____ , Snd Vice-President..... ..... Treasurer_____ _________ Secretary_______ ...... ..... --......_H. P. Gant. --Homer Addams ___ E. E? McNair ...Wm. H. Driscoll _____ C. W. Obert Council __ Chairman, H. P. Gant Homer Addams, Vice-Chm. E. S. Hallett W. H. Carrier Alfred Kellogg J. A. Cutler Thornton Lewis S. E. Dibble E. E. McNair Wm. H. Driscoll Perry West Casin W. Obert, Secy. President_________ _ 1st Vice-President ' Snd Vice-President.. Treasurer________ __ Secretary___________ --Homer Addams ...S. E. Dibble ..William H. Driscoll ......... ........ Perry West --------F. C. Houghten Council Chairman. Homer Addams S. E. Dibble, Vice-Chm. W. E. Gillham F. Paul Anderson L. A. H' arding W. H. Carrier Alfred Kellogg J. A. Cutler Thornton Lewis William H. Driscoll Perry West . H. P. Gant F. C. Houghten,' Secy. President................... 1st Vice-President__ Snd Vice-Presidents Treasurer_______ . Secretary.__________ _____ A. C. Willard __ Thornton Lewis ____ L. A. Harding ____W. E. Gillham --A. V. Hutchinson Council . Chairman, A. C. Willard -Thornton Lewis, Vice-CAm. C. V. Haynes F. Paul Anderson John Howatt H. H. Angus . W. T. Jones . W. H. Carrier J. J. Kissick N. W. Downes E. B. Langenberg Roswell Farnham J. F. Mclntire W. E. Gillham H. Lee Moore F. B. Rowley 1st Vice-President__ Snd Vice-PresidentTreasurer__________ SecretaryTechnical Secretary__ ___ Thornton Lewis -....... T. A. Harding _____ W. H. Carrier ____ .W. E. Gillham --A. V. Hutchinson ________P. D. Close President__________ 1st Vice-President__ Snd Vice-President_ Treasurer.__________ . Secretary_________ _ ______ S. E. Dibble __Wm. H. Driscoll _F. Paul Anderson Perry West ___F. C. Houghten Council Chairman, S. E. Dibble. Wm. H. Driscoll, Vice-Chm. W. T. Jones Homer Addams Thornton Lewis F. Paul Anderson J. H. Walker W. H. Carrier Perry West J. A. Cutler W. E. Gillham A. C. Willard Houghten, Secy. President 1st Vice-President__ Snd Vice-President_ Treasurer____, , , , Secretary___________ 1926 W; H. Driscoll . Paul Anderson ___ ,,W. E. Gillham --A. V. Hutchinson Council Chairman, W. H. Driscoll F. Paul Anderson. Vice-Chm. C. V. Haynes W. H. Carrier "W*. ~T. J'ones J. A. Cutler E. B. Langenberg S. E. Dibble Thornton Lewis W. E. Gillham J. F. Mclntire A. C. Willard Council Chairman, Thornton Lewis L. A. Harding, Vice-Chm. John Howatt H. H. Angus W. T. Jones W. H. Carrier - * E. B. Langenberg N. W. Downes G. L. Larson Roswell Famham . F. C. McIntosh W. E. Gillham W. A. Rowe C. V. Haynes F. B. Rowley . A. C. Willard Treasurer Technical Secretary- 1930 . IL.. Afi . Harding w F r A VU P Council Chairman, L. A. Harding W. H. Carrier, Vice-Chm. ' John Howatt H. H. Angus W. T. Jones D.' S. Boyden E. B. Langenberg R. H. Carpenter G. L. Larson J. D. Cassell Thornton Lewis N. W. Downes F. C. McIntosh Roswell Famham W. A. Rowe C. W. Farrar F. B. Rowley 95 HEATING VENTILATING AIR CONDITIONING GUIDE 1940 1931 1st Vice-President__ Snd Vice-President 'Treasurer................... Secretary_ Technical Secretary..__ _____ W. H. Carrier ____ ..F. B. Rowley ______ W. T. Jones ____ F. D. Mensing _A. V. Hutchinson ...=_____ P. D. Close Council Chairman, W. H. Carrier F. B. Rowley, Vice-Chm. L. A. Harding -D. S. Boyden John Howatt E. K. Campbell W. T. Jones R.H. Carpenter E. B. Langenberg J. D. Qggyii G. L. Larson E. O. Eastwood F. C. McIntosh Roswell Farnham F. D. Mensing E. H. Gumey W. A. Rowe 1st Vice-President__ Snd Vice-President... Treasurer_________^ Secretary_ Technical Secretary__ ___F. B. Rowley ______.W. T. Jones _____ C. V. Haynes ____F. D. Mensing _A. V. Hutchinson _______ P. D. Close Council Chairman, F. B. Rowley W. T. Jones. Vice-Chm. ' F. E. Giesecke D. S. Boyden E. H. Gurney E. K. Campbell C. V. Haynes R. H. Carpenter John Howatt W. H. Carrier G. L. Larson John D. Cassell J. F. Mclntire E. O. Eastwood F. D. Mensing Roswell Farnham W. E. Stark President____ _____ ,,W. T. Jones 1st Vice-President__ _C. V. Haynes Snd Vice-Presidents .John Howatt Treasurer________________D. S. Boyden Secretary___ A. V. Hutchinson Council Chairman, W. T. Jones ;C. V. Haynes, Vice-Chm. E. H. Gurney D. S. Boyden J'o'hn "Howatt E. K. Campbell G. L. Larson R, H, Carpenter J. F. Mclntire J. D. Cassell F. C. McIntosh E. O. Eastwood ` 1 UW. Moon R. Farnham F. Bl Rowley F. E. Giesecke W. E. Stork President..................... "John Howatt 1st Vice-President..... ____-__ G. L. Larson 2nd Vice-President ______ D; S. Boyden Treasurer....... ............. ________A.'J. Offner Secretary____ ._A. V. Hutchinson Council Chairman, John Howatt G. L. Larson, Vice-Chm. ' C. V. Haynes M. C. Beman J. F. McIntire D. S Boyden F. C. McIntosh Albert Buenger R. H. Carpenter L. Walter Moon A. J. Offner J. D. Cassell O. W. Ott F. E. Giesecke W. A. Russell E. H. Gurney W. E. Stark 1st Vice-President__ 1936 ,,G. L. Larson ,,D. S. Boyden Snd Vice-President_ Treasurer___ ______ Secretary.__________ _E. H. Gurney _A. J. Offner _A. V. Hutchinson Council Chairman, G. L. Larson D. S. Boyden, Vice-Chm. John Howatt M. C. Beman C. M. Humphreys R. C. Bolsinger L. Walter Moon Albert Buenger J. F. Mclntire S. H. Downs A. J. Offner W. L. Fleisher O. W. Ott F. E. Giesecke W. A. Russell E. H. Gurney W. E. Stark President___________ 1st Vice-President__ 2nd Vice-President.^ Treasurer__________ Secretary____ 1937 ,D. S. Boyden _E. Holt Gurney J. F. Mclntire ,,A. J. Offner __A. V. Hutchinson Council - - . Chairman, D. S. Boyden E. H. Gurney. Vice-Chm. E. O. Eastwood J. J. Aeberly W. L. Fleisher M. C. Beman F. E. Giesecke R. C. Bolsinger Albert Buenger C. M. Humphreys G. L. Larson S. H. Downs W A'. Russell W. E. Stark - 1938 President__ ______ _____________ ____E. Holt Gurney 1st Vice-President_____________ ___ __J. F. Mclntire 2nd Vice-PresidentF. E. Giesecke Treasurer___ _______ ___________ -----------A. J. Offner Secretary;A. V.. Hutchinson Technical Secretary_____............... ....... ...John James Council Chairman. E. Holt Gurney J. F. Mclntire. Vice-Chm. . W. L. Fleisher N. D. Adams -F. .E. Giesecke J. J. Aeberly . ' C. M. Humphreys M. C. Beman ' . R. C. Bolsinger A. P. Kratz A. J. Offner D. -S. Boyden W. A. Russell S. H. Downs J5. O. Eastwood J. H. Walker G; L. Wiggs President... 1st Vice-President. 2nd Vice-President. Treasurer. Secretary. Chairman, C. V. Haynes John Howatt, Vice-Chm. W. T. j M. C. Beman G. L. ___ D. S. Boyden J. F. MclntiH Albert Buenger F. C. McIntosh R. H.. Carpenter L. Walter Moon ' J. D. Cassell O. W. Ott F. E. Giesecke W. A. Russell E. H. Gurney W. E. Stark 1939 nt...................................................J. F..Mclntire l'S&tk-President.................................. F. E. Giesecke SM&ttc-President.................................W. L. Fleisher. rrmffijp...................................................M. F. Blankin. SeGfegmy.""............................. ........... A. V. Hutehinson> TeliytTial Secretary..................................... John James A/ Council . ' -'"J Chairman. J. F. Mclntire .. Giesecke. Vice-Chm. W. L. Fleisher ,, fD. Adams - E. H. Gurney J. J. Aeberly A. P. Kratz M. C. Beman A. J. Offner M. F. Blankin W. A. Russell E. K. Campbell G. L. Tuve S. H. Downs J..H. Walker E. O. Eastwood ' G. L. Wiggs 96