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264 CHAPTER 12 1955 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 of Varioos 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 26. 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 25, Chapter 13. For appliances see Table 26, 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 to which these are to be heated.15 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 rop" wind velocity. Inside temperature from Table 2 is assumed to be 70 F. The attic unheated. Assume ground temperature to be 50 F (see Fig. 3, Chapter 35) uau& basement and garage floors and 32 F adjoining basement walls. Estimate infiltration losses 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 garagc> r Heating Load 265 Table 8.- Heat Loss Calculation Sheet for Uninsulated Residence (Fig. 2) A Room or . Space Bedroom A and Closet Bedroom B aod Closet Bedroom C and Closet Bedroom D and Closet Bathroom 1 Bathroom 2 Living Room Lining Room Kitchen and Entrance Garage uytto and Vestibule Entrance Hall Uarage 3reation Room* -----_____ 1. B . tC D E F G Part op Structure or Infiltration Air Changes Net Area or Air Volume , Co Em CI ENT Temp. Diff. Walla Class Ceiling . Infiltration (H)* 236 sq It 40 sq ft 252 sq ft 1610 cfhb 0.28 0.45 0.69 0.018 80 8 . 39.3d 80 Walla Glass Ceiling Infiltration (M)* 166 sq ft 40 sq ft 170 sq ft .1020 cfhb 0.28 0.45 0.69 0.018 80 80 ^ 80 Walla GlassCeiling Infiltration (H)* 114 sq ft 27 sq ft 129 sq ft 87Icfbb 0.28 0.45 0.69 0.018 80 so , 39.8* 80 Walls Glass Ceiling Floor over garage Infiltration (H)* 118 sq ft 20 aq ft 110 sq ft 110 sq ft 6S0rfhb 0.28 0.45 0.69 0.25 0.018 80 80 ^ 39.3d 35* 80 Walls Glass Ceiling Infiltration (I)* 30 sq ft 14 sq ft .56 sq ft 440cfhb 0.28 0.45 0.69 0.018 80 80 -A 39.8* 80 Walla Glass Ceiling Floor over garage Infiltration (1)* 79 eq ft 9 sq ft 35 sq ft 35 sq.ft ' 280cfnb 0.26 0.45 0.69 0.25 0.018 80 80 39.3d 35 80 Walla Walls (adjoining garage) Glass Floor Infiltration OH)1* 267 sq ft 94 aq ft 50 sq ft 294 sq ft 3745 cfhb 0.28. 0.39* 0.45 0.018 80 35 80 80 Walls Glass (doors) Glass (windows) Floor Infiltration (lH)' 166 sq ft 35 sq ft 20 sq ft 168 sq.ft 2140 cfnb 0.28 0.85 0.45 0.018 80 80 80 . 80 Walls Walls (adjoining garage) Glass Door Floor Infiltration OH)' 96 sq ft 51 sq ft 18 sq ft 17 sq ft 125 sq ft 1595 cfhb 0.28. 0.39* 0.45 0.51 0.018 80 35 80 35 80 Walls Walls (adjoining garage) Glass Door Floor Infiltration OH)* 82 sq ft .. 85 sq ft 9 sq ft 19 sq ft 30 sq .ft 383 cfhb 0.28, 0.39( 0.45 0.51 0.018 80 35 80 80 80 Walls Door Ceiling*1 Infiltration (2)* 39 sq ft 21 sq ft 87 sq.ft 1110cfhb 0.28 0.38 0.69 0.01S 80 80 39.3d 80 Walla Glass Doors Infiltration (1H)" Floor Gain adjoining rooms 167 sq ft 53 sq ft 44 sq ft 2360 cfhb 29 ft*; 0.28 1.13 0.51 0.018* 0.81 45 45 45 4$ 45 Walls Glass Floor Infiltration (1) 220 sq ft 8 sq ft 287 sq ft 2010 cfhb 0.10 1.13 0.10 0.018 38 80 20 80 Heat Loss (Btu per .hour). 5330 1440 6910 2180 3490 1440 4660 1470 2560 970 3540 1260 2650 720 3020 960* 950 670 500 1510 630 1640 320 960 310 400 5980 1280* 1800 5400 3720 2380 720 3080 2150 700* 650 300 2300 1840 U6QP 320 780 550 870 640 2390 1600 2110 2700 1010 1910 1060 -4410* 840 720 570 2890 Totals (Btu per - - hour) 15,860 11,060 8.330 8.300 3,310 3,630 14,460 9,900 6,100 4.650 5.500 4,380 5,020 TOTAL 100,500