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282 CHAPTER 12 .1958 Guide 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. This heat is retained in the room if the product 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 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. Table 7 shows the heat output equivalent Table 7. Heat Equivalents op Various Sources* Machinery (Motor in room) = Motor Hp/efficiency x 2544 Btu/hr. , Machinery (Motor outside room) = Motor Hp x 2544 Btu/hr. Electric Lights = Kilowatts x 3413 Btu/hr. Gas (Producer = 150) (Manufactured = 535) (Natural = 1000) Btu/cu ft. Additional values are given in Chapter 13,Table 28. of various sources of heat in a factory. For information concerning the heat supplied by persons, refer to data given in Chapter 6, and also Table 27, Chapter 13. For appliances see Table 28, Chapter 13. INTERMITTENTLY HEATED BUILDINGS In the case of intermittently heated buildings additional heat is required for raising the temperature of the air, the building materials and the ma terial contents of the building, to the specified. inside temperature. The rate at which this additional heat must be supplied depends upon the heat capacity of the structure and its material contents, and upon the time in which these are to be heated.16 This additional heat'may be computed and allowed for as conditions re quire, but inasmuch as the heating system proportioned for taking care of the heat losses will usually have a capacity about 100 percent greater than that required for average winter weather, and inasmuch as most buildings may either be continuously heated or have more time allowed for heating up during the few minimum temperature days, no allowance usually is made, except in the size of boilers .or furnaces. For churches, auditoriums and other intermittently heated buildings, additional capacity should be provided. RESIDENCE HEAT LOSS PROBLEMS The following Examples 6 and 7 will illustrate the procedure for calcu lating the heat loss of a residence, uninsulated and insulated, in accordance with the recommendations given in this chapter. Example 6: Calculate the heat loss of the residence shown in Fig. 2 located in the vicinity of Chicago. From Table 1, design outdoor conditions are --10 F and 12 mp*> wind velocity. Inside temperature from Table 2 is assumed to be 70 F. The attic is unheated. Assume ground temperature to be 50 F (see Fig. 3, Chapter 34) under basement and garage floors and 32 F adjoining basement walls. Estimate infiltrationlosses by the air change method. No wall, ceiling or roof insulation is to be con-sidered in this problem, but all first and second floor windows, except in the garage.' Heating Load 283 Table 8. Heat Loss Calculation Sheet for Uninsulated Residence (Fig; 2) A Room ob Space Bedroom A and Closet Bedroom B and Closet Bedroom C and Closet Bedroom D and Closet Bathroom 1 Bathroom 2 Living Room Dining Room Kitchen and Entrance to Garage Lavette and Vestibule Entrance Kali Garage Recreation Room** ! B. C D E F|G Past op Stbuctubb ob Infiltbation Aib Changes Walls Glass Ceiling Infiltration (H)9 Walls Glass Ceiling Infiltration (%)* Walls Glass Ceiling Infiltration (H)9 Walls Glass Ceiling Floor over garage Infiltration (H)9 Walls Glass Ceiling Infiltration (1)* Walls Glass Ceiling Floor over garage Infiltration (1) Walls Walls (adjoining garage) Glass Floor Infiltration (lH)h Walls Glass (doors) Glass (windows) Floor Infiltration (1*$)* Walls Walls (adjoining garage) Glass Door Floor Infiltration (1HP Walls Walls (adjoining garage) Glass Door Floor Infiltration (lH)k Walls Door Ceiling1 Infiltration^)1 Walla Glass Doors Infiltration (1H)" Floor Gain adjoining rooms Walls Glass Floor Infiltration (1) Net Abba ob Aib Volume Coeffi Temp. cient Diff. 238 8Q ft 40 sq ft 252 sq ft 1510 cfh*> 0.29 0.45 0.74 0.018 80 80 , 39.8^ 80 156 sq ft 40 sq ft 170 sq.ft 1020 cfhb 0.29 0.45 0.74 0.018 80 80 ^ 39.8* 80 114 sq ft 27 sq ft 129 sq ft '874 cfhb 0.29 0.45 0.74 0.018 80 3809.3^d 80 118 sq ft 20 sq ft 110 sq ft 110 sq.ft 680 dhb 0.29 0.45 0.74 0.26 0.018 80 8 , 39.8* 35* 60 30 sq ft 14 sq ft 55 sq.ft 440 <5hb 0.29 0.45 0.74 0.018 80 80 ^ 39.8* 80 79 sq ft 9 sq ft 35 sq ft 35 sqjt 280 cffib 0.26 0.45 0.74 0.26 0.018 80 8 . 39.3d 35 80 267 sq ft 94 sq ft 50 sq ft 294 sq.ft 3745 cfhb 0.29. 0.39f 0.45 0.018 80 35 80 80 166 sq ft 35 sq ft 20 sq ft 168 sq.ft 2140 cfhb 0.29 0.85 0.45 0.018 80 80 80 80 96 sq ft 51 sq ft 18 sq ft 17 sq ft 125 sq ft I595cfhb 0.29. 0.39* 0.45 0.51 0.018 80 35 80 35 80 82 sq ft 85 sq ft 9 sq ft 19 sq ft 30 sq.ft 383cfnb 0.29 0.391 0.45 0.51 0.018 80 35 80 80 80 39 sq ft 21 sq ft 87 sq.ft 1110cfhb 0.29 0.38 0.74 0.018 80 3809.3^d 80 167 sq ft 53 sq ft 2360 elU* 29 ft* 0.29 1.13 0.51 0.018 0.81 45 45 45 45 45 220 sq ft 8 sq ft 287 sq ft 2010 cfbb 0.10 1.13 0.10 0.018 38 80 20 80 Heat Loss (Btu per boar) Totals (Btu per hour) 5520 1440 7410 2180 16,550 3620 1440 5000 1470 . 11.530 2650 970 3800 1260 8,680 2740 720 3240 960p 950 8,610- 690 500 1620 630 3,440 1640 320 1060 320p 400 3,740 6200 1280p 1800 5400 14,680 3850 2380 720 3080 10,030 2220 700p 650 300 2300 6,170 1900 1160P 320 780 550 4,710 900 640 2560 1600 5,700 2180 2700 1010 1910 1060 --4420p 4,450 840 720 570 2890 5,020 1 | TOTAL | 103,310