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486 CHAPTER 26 1965 Guide And Data Book Table 10------ Summary of Heat loses of Insulated Residence (Btu Per Hour) Hoorn or Spats WdJs CeUing and Hoof Floor Gfcm JrSDoer tralioB Tofah ` Temperature and Wind Frequency Table* for North America and Greenland (Vols. 1 and 2, Arctic Meteorology Research Group, Publication in Meteorology Nos. 24 and 25, McGill Uni versity, 1960). 1 Evaluated Weather for CooUngEquipment Design, Addendum No. t. Summer and Winter Data (Fluor Products Company, Santa Rosa, Calif.,1964). Bedroom A Bedroom B Bedroom C Bedroom D 2620 1720 1260 1300 Bathroom 1 Bathroom 2 Living Room Dining Room 330 870 3630 1830 2770 1870 1470 1220 610 280 1530 2310 1530 1560 1030 1340 790 770 1010 540 670' 250 340 430 1910 5730 3300 3270 I M. K. Thomas: A method for determining winter design ' temperatures (AfiHAE Transactions, Vol. 61, 1955, p. 387). * A. P. Krat* and S. Konzo: Investigation of Oil-Fired Forced Air Furnace Systems in the Research Residence (University.of 5,090, ' Illinois, Engineering Experiment Station Bulletin No. 318). * A. P. Kratz, - w. S. Harris, M.. K. Fahnestock, and R. J. Martin*. Performance of a Hot-Water Heating System in the I-B-R - Research Home at the University of Hanoi* (University of Illinois, EngvneervngExperunent Station Bulletin No. 349). II A. P. Krais and W. 8. Harris: A Study of Radiant Baseboard Heating in the I-B-R Research Home (University of Illinois, 8,400 Engineering Experiment Station Bulletin No. 358). KitoW lAvette Entrance H*11 Garage Recreation 1430 1520 430 -580* 950 960 --1040* 1180 720 1040 1160 680 4120 770. 2440 1700 2120 3080 4,910 3^770 5,520 Design Totals 17,310 Operating Totals* 17,310 Percentages4 28.7 8,140 2,940 18,720 26,250 73,360 8,140 2,940 18,720 13.5 4.9 31.1 21.8 100.0. , 1080 Btoh missa* inHhcoA 4 BBmmId fosnltsompe7r9s0timtatdota2l5*.0 Btub. * Rfcwd on }cif 680,3TO, aad610 Btoh.~ 'eotnpnted infiltntioa. " W. S. Harris: Performance of a One-Pipe Steam System in the I-B-R Research Home (University of Illinois, Engineering Experiment Station Bulletin No. 383). " G. L. Larson, D. W. Nelson, and John James. ASHVE Research Report No. 1011--Tests of three heating systems in . an industrial type of building (ASHVE Transactions, Vol 41, 1935, p. 185). u F. A. Joy, J. J. Zabrony, and 3. Bhaduri: Insulating Value of Reflective Elements in an Attic Under Winter Conditions (Penn sylvaniaState University, October 1956). u F. A. Joy: Improving attic space insulating values (ASHAE Journal Section, Heating, Pipxng and Atr Conditioning, Janu ary 1958, p. 223). u F. B. Rowley, A. B. Algren, and C. E. Lund: Methods of Moisture Control and Their Application to Building Construc tion (University of Minnesota, Engineering Experiment Station Bulletin No. 17). i irttrtjenftA, the clast and door transmission heat losses of 19.8 per cent are relatively smalL The infiltration losses of 14.0 percent are also comparatively small because the storm windows are equivalent to weatherstripping. In this problem, the wall, ceiling, and floor transmission loses comprise 66.2 percent of the .total Example 7: Calculate the heat loss of residence shown in Fig. 1, based on the same'conditions as in Example 6, but having constniction improved or insulated to; obtain coefficients as follows: : Walls, 0.13; Wall* of Dormer oner Oarage, 0.12; Attic Wallt, 0.28; Walls Adjoining Garage, 0-18; Basement Walls (Recrea tion Room), 0.10. ' Rod, 0.83. CeMng (Second Floor), 0.15. Windows (Same as in Example 8). ' Floor (Bedroom D),- 0.18. Solution: The procedure for calculating the heat losses is gimilar to that for Example 6. A summary of the results is given in Table 10.. REFERENCES 1 Evaluated Weather Data for Cooling Equipment Design, (Fluor Products Company, Santa Rosa, Calif., 1958,1sted.), " * Engineering- Weather Data, (Army, Navy, and Air Force Manual TM 5-785, 1963). * * L. 'W. Crow: Study qf Weather Design Conditions, (ASHRAE Research Project No. 23, Bulletin 1963). * D. W. Boyd': Climatic Informationfor Building Design to Can ada, (Supplement No.! 1, National Building Code of Canada, National Research Council, Ottawa). " F. C. Houghten, S. I. Taimuty, Carl Gutberlet, and C. J. Brown: ASHVE Research Report No. 1213--Heat loss through basement walls and floors (ASHVE Transactions, VoL 48,1942, p. 369). 17 W. D. Collins: Temperature of water available for industrial use in the United States'(U. S. Geological Survey Water Supply Paper No. 520 F). u R. 8. Dili, W. C. Robinson, and H. E. Robinson: Measure ments of Heat Losses from Slab Floor (U. S. Department of Commerce, National Bureau of Standards, Building Materials and Structures Report BMS 103). 11 H. D. Bareither, A. N. Fleming; and B. El Aiberty: Tem perature and Heat Loss Characteristic* of Concrete Floors Laid on the Ground (University of-Illinois, Small Home* Council Technical Report). 11 Concrete Floors for Basementle** House* (University of Illinois, Small Home* Council Circular No. F 4.3). a J. R.' Jamieson, R. W. Roose, and S. Konzo: Warm-air perimeter beating, Part 111--Heat losses from floor slab ASHVE Transactions, VoL 58, 1952 p. 217). a Warm-Air Perimeter Heating (National Warm Air Beat ing and Air Conditioning Association, Manual 4). ** Slab-on-Ground Construction far Residence* (Building Re search Advisory Board, National Research Council, Publica tion No. 385). M Heat Requirement Table* for Intermittently Heated Build ing* (A. and M. College of Texas, College Station, Texas, En gineering Experiment Station Bulletin No. 60) contains a set of tables applicable to either; intermittent heating or cooling. ' Further information maybe found in a paper by E. G. Smith: A method of compiling tables for intermittent heating (ASHVE Journal Section, Heating, Piping and Air Conditioning, June 1942, p. 386). CHAPTER 27 AIR-CONDITIONING COOLING LOAD COMMERCIAL AND fNDl/STR/Al COOLING LOAD CALCULAT/ONS; Design Conditions; Instantaneous Heat load; Solar Radiation; Periodic Heat Flow; Tables for Calculating Solar Heat Gain Through Walls, Roots, and Glass; Instantaneous Heat Gam vs Cooling loads; Load from Interior Partitions, Ceiling, and Floors; Load from Outdoor Air, Ventilation and Infiltration} Effect of Outdoor Air on Load; Heat Sources Within Conditioned Space; Moisture Transfer Heat Load; Miscellaneous Heat Loads; Apparatus Dew Point and Required Air Quantity Through Conditioning Eguipmenf,Minimum Entering Air Temperature; Example Cooling Calculation; RESIDENTIAL COOLING LOADS: Interpretation of Data; Design Temperatures; Equivalent Temperature Differential*; Heat Gains; Infiltration and Ventilation; Occupancy Loads; Total Cooling Load THIS chapter discusses the methods and data used for COOLING LOAD CALCULATIONS calculation of air-conditioning cooling loads for both com fort and prooess applications. Part I HpaI* with the loads commercial and industrial buildings and processes. Part II foror Scuommmfoerrt cooling load applications, calculations, whether for require consideration of: industrial deals with the load for residential cooling. 1. Design Condition*: (a) indoor conditions, (b) outdoor conditions (Table 1), (c) ventilation rate (Table 2). PART I: COMMERCIAL AND INDUSTRIAL 2. Instantaneous Heat Load, Sensible and Latent: (a) load from eolar radiation, sky radiation, and from outdoor-indoor COOLING LOADS temperature differential for glass areas and exterior walls and roofs, modified by periodic heat flow or lag factors, depending The variables affecting cooling load calculations are numerous, often difficult to define precisely, and always intri on the type of structure, (b) load due to heat gain through interior partitions, ceilings, and floors, (c) load due to ventila tion, either natural or mechanical (d) toad due to heat sources cately interrelated. Many of the components of the cooling within the conditioned space- such as people, lights, power load vary in magnitude over a wide rangeduring a 24-hour period, and as the cyclic changes in load components are not usually in phase with each other, careful analysis is required equipment, and appliances, (e) load due to moisture transfer through permeable building materials, and (0 miscellaneous heat sources. 3. Determination ofAir Quantity and Apparatus Dear Paint. to establish the resultant maximum cooling load for a building or zone. A zoned system must often handle peak loads in These factors will be discussed in turn. The material pre different zones at different hours. sented leads to an illustrative procedure for a cooling load Economic considerations mist be of particular influence in calculation, and a numerical example is given to demon the selection of equipment for cooling season operation in strate the calculations involved. comfort air conditioning, and this fact, coupled with present inadequacies in available data and knowledge of the air- DESIGN CONDITIONS conditioning art, places a premium on the experienced judg ment essential to successful design or practice. Variations in the weather, building occupancy, and other factors affecting load, necessitate carefully coordinated controls to regulate simultaneously the components and the equipment in order to maintain the desired room conditions. The calculation procedures presented in this section deal with the various instantaneous rates of heat gain, both sen sible and latent, in a conditioned space. There may be an appreciable difference between the net instantaneous rale of heat gain and the total coding load at any instant. This differ ence is caused by the. storage and subsequent release of heat by the structure and its contents. This thermal-storage effect may be quite important in determining an economical cooling equipment capacity. This effect has been demonstrated by investigators using thermal circuit techniques and com puters.*-11 The lack of any adequate means of treating this storage analytically in its entirety for a complete structure must be recognized in judging the procedures and data pre sented for calculating individual components of the net rate of ingfamtaflapys frpftfr'gwm Indoor Conditions Indoor air conditions for human health and comfort con tinue to be the subject of discussion and research. Research at the ASHRAE Research Laboratory1* concludes that, for inactive individuals, lightly clothed in still-air con ditions, the line of optimum comfort ranges from 77.6 F at 30 percent relative humidity to 76.5 F at 85 percent relative humidity. It is only slightly dependent on humidity. This . research was based on 3-hr exposures to constant conditions in a room where the walls were held at room air temperatures; whereas earlier research resulting in the Effective Tempera ture Chart was based on subjective reactions to sudden tem perature change. < s' Indoor design conditions, for .which summer air-condi tioning equipment is selected, should preferably be chosen at 75 F dry-bulb, with a relative humidity of 50 percent for the average job in the United States and Canada. In arid climates, a design relative humidity of 40 percent should be chosen. The 75 F design dry-bulb temperature, which is slightly lower than the optimum range of 76.5 to 77.6 (with walls at Solar heating calculations involve the same principles as cooling load calculations. Many of the data on solar radiation given in this section can be used in calculations for solar heating room temperature), will partially compensate for the higher mean radiant temperatures normally encountered in comfort cooling applications. For brief occupancy only, a higher drybulb temperature may be chosen, although complaints of dis Th* CBaenT roponabilitv for tU* eh&ptr U wtgwrt to TC J.l. Load Cofeulatum Dot* *od Fumciiiw; TC X2. Weather Data and Dcaicn Coodi- ttan*; and TC 24, Feneetralm. . .v comfort may be expected with continuous occupancy. (Continued on p. 4&4). -i 487