Document bOB4dGZZ5XmVNowew4OzYny06

HEATING VENTILATING AIR CONDITIONING GUIDE .1940 Table 1. Summary_>i; .Data Applied to Warm.: Air Research Residence From Rooms Chapter 7 Estimating Heat Losses Btu Leader Area . Sq In. Stack Aied Sq In. 0.7 X LA Leader Diameter Inches Stack Size Net. . .Register . Size -. Gross'- tit Heat Losses mi H First Floor = 0.00917 17250 . 6810 155 61 ' 14 9 14 X 16 8 X 12 SI Breakfast___ 2300 Kitchen__ -- 9210 25710 21 ' 83,__ 230 8 11 or 12 .......... 8X10 12 X 14 Two 12 X 14 Hall and stair 12570 113 12 12 X 14' Second Floor = 0.00617 Owner's____ 15030 90 63 11 or 12 5 X 12 12 X 14 S. W. Bed___ 9800 59 41 9 3tf X 12 8*12 Bath..---------- 2450 15 . : 10 -8 3 X 10 8X10 i N. Bed_____ 14800 Third Floor E. Bed______ .. . 8220 . W. Bed..------ 8220 89 = 0.00517 41 41 62 29 29 11 or 12 8. 8 5 X 12 3 X 10 3 X 10 12 X 14 8 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 per 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. 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 j.,,., ........ - 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 fansv instead of by the difference in weight between the heated air leaving/tne'.fop .'of the casing and 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 dehumidifying system for summer, using either ice, mechanical refrigeration, or low temperature water for cooling and dehumidifying, or adsorbers for dehumidifying. 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. 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. `See University of Illinois, Engineering Experiment Station Bulletin No. 266 by A. P. Kratz and S. Konzo for details of tests conducted in Warm Air Research Residence. 363