Document wq9RkR3BzJq1RkQBn7vjgJ2X4

492 CHAPTER 19 1958 Guide Table 4. Btuh Capacities and Cfm of Individual Ducts in Pebimeter Systems Used in Cbawl-Space or Basement Construction section A. FOR 5-INCH individual round pipe and for sidewall, floor, and BASEBOARD DIFFUSERS Bonnet Protore 0.16 in. Static Bonnet Temperature 170 F No. OFElbows Actual Length of Pipe from Bonnet to Diffuser--Feet 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 0 Btuh Cfm 8700 7900 7150 6450 5800 5230 4700 4230 3830 3470 3150 2860 2600 100.5 96.2 92.7 89.7 87.0 84.6 82.5 80.4 78.4 76.5 74.8 73.2 71.7 1 Btuh Cfm 8620 95.8 7800 91.7 7100 88.7 6470 86.0 5830 83.8 5350 81.6 4850 79.7 4370 77.7 3960 76.0 3600 74.2 3260 72.5 2950 71.2 2650 69.8 2360 68.5 2 Btuh Cfm 8700 7900 7180 6530 5950 5400 4920 4430 4050 3680 3350 3040 2750 2480 2220 90.8 87.9 85.2 .82.7 80.7 78.9 77.1 75.4 73.6 72.0 70.5 69.2 67.9 66.7 65.6 3 Btuh Cfm 8800 8000 7300 86.6 84.0 81.5 6650 79.3 6070 77.5 5530 75.8 5050 74.3 4600 72.8 4180 71.3 3800 70.0 3440 68.7 3120 67.5 2830 66.3 2550 65.2 2300 64.1 2060 63.0 4 Btuh 8250 7520 6850 6230 5680 5180 4720 4300 3900 3550 3220 2900 2630 2360 2120 1880 . Cfm 81.0 78.8 77.0 75.3 73.7 72.2 70.8 69.5 68.2 67.2 66.0 65.0 63.6 62.5 61.5 60.5 5 Btuh Cfm 7720 7050 6420 5840 5330 4850 4430 4030 3650 3320 3020 2730 2460 2200 1950 1730 76.4 74.5 73.0 71.6 70.3 69.0 67.8 66.6 65.5 64.4 63.2 62.0 61.2 60.2 59.2 58.1 6 Btuh 7280 6630 6070 5530 5050 4600 4180 3800 3470 3150 2850 2550 2280 2050 1820 1600 Cfm 72.6 71.2 69.8 68.5 67.3 66.0 -64.7 63.5 62.4 61.4 60.5 59.5 58.1 57.8 57.0 56.3 The Equivalent length Values used and included in calculating this table are: DiEuser and Boot = 35 ft; Plenum Takeoff = 15 ft; Each Elbow = 12 ft. For each additional 12 ft equivalent length of boot and diffuser count one additional elbow. All cfm values are based on standard air. SECTION B. FOR 6-INCH INDIVIDUAL ROUND PIPE AND FOR SIDEWALL AND FLOOR DIFFUSERS Bonnet Pressure 0.16 in. Static Bonnet Temperature 170 F No. 07 Elbows Actual Length of Pipe from Bonnet to Diffuser--Feet 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 0 Btuh Cfm 1 Btuh Cfm 2 Btuh Cfm 3 Btuh Cfm 4 Btuh Cfm . 5 Btuh Cfm 6 Btuh Cfm 8700 8060 7460 6920 6430 5960 5550 127.7 124.8 122.3 119.7 117.4 115.0 113.0 8620 8000 7430 6900 6400 5930 5500 5100 122.8 120.0 117.6 115.3 113.0 111.0 109.0 107.3 8600 7960 7390 6860 6380 5940 5530 5150 4800 118.5 116.2 114.0 112.0 110.0 107.8 106.0 104.5 103.0 8640 8020 7450 6950 6460 6020 5600 5200 4850 4500 114.0 112.0 110.0 108.2 106.5 104.7 103.0 101.4 99.6 98.0 8760 8160 7580 7050 6540 6080 5640 5250 4880 4550 4250 110.2 108.4 106.6 105.0 103.0 101.5 100.2 99.0 97.5 96.0 94.5 8850 8250 7670 7140 6640 6170 5740 5340 4960 4620 4290 3990 106.8 105.0 103.5 102.0 100.5 99.0 97.5 96.0 94.6 93.4 92.0 91.0 9050 8420 7840 7280 6750 6300 5850 5440 5060 4700 4370 4060 3760 104.0 102.5 100.7 99.2 97.8 96.5 95.2 94.0 92.6 91.4 90.0 88.7 87.5 The Equivalent Length Values used and included in calculating this table are: Diffuser and Boot = 40 ft; Plenum Takeoff => 20 ft; Each Elbow =* 14 ft. For each additional 14 ft. equivalent length of boot and diffuser count one additional elbow. All cfm values are based on standard air. calculate its heat loss. Information in Manual 3 supplements that contained in Chapter 12, particularly with respect to crawl space neat losses. 2. Determine the required furnace-bonnet capacity from the heat loss of the building. 3. Locate the diffusers on the plan. Allow at least one diffuser for each exposed Warm Air Heating Systems 493 Table 4. Btuh Capacities and Cfm of Individual Ducts in Perimeter Systems Used in Crawl-Space or Basement Construction {Concluded) SECTION C. FOR 6-INCH INDIVIDUAL ROUND PIPE AND FOR BASEBOARD DIFFUSERS ONLY Bonnet Pressure 0.15 in. Static Bonnet Temperature 170 F No. OF Elbows Actual Length of Pipe from Bonnet to Diffuser--Feet 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 0 Btuh Cfm 1 Btuh Cfm 2 Btuh Cfm 3 Btuh Cfm 4 Btuh Cfm 5 Btuh Cfm 6 Btuh Cfm 8570 8000 7450 6910 6420 5960 5560 5150 4800 4450 4160 109.0 107.2 105.5 103.7 102.0 100.4 98.8 97.5 96.1 94.8 93.5 8700 8100 7550 7000 6520 6060 5630 5250 4860 4530 4220 3930 105.5 104.0 102.3 100.7 99.2 97.6 96.2 95.0 93.6 92.3 91.1 90.0 8890 8270 7700 7160 6660 6200 5750 5350 4980 4620 4300 4000 3700 102.8 10^.3 99.8 98.2 96.7 95.3 94.0 92.7 91.5 90.2 89.0 87.8 86.5 8440 7870 7320 6820 6350 5880 5460 5070 4700 4350 4020 3710 3440 98.4 96.8 95.3 93.9 92.5 91.3 90.0 89.0 88.0 86.9 85.8 84.7 83.5 8690 8080 7500 6980 6500 6030 5580 5180 4800 4450 4120 3820 3520 3250 95.8 94.4 93.0 91.6 90.3 89.0 87.8 86.7 85.7 84.6 83.7 82.6 81.6 80.5 8940 8320 7740 7200 6680 6190 5720 5320 4920 4550 4220 3890 3600 3350 3100 93.4 92.2 91.0 89.8 88.5 87.3 86.2 84.8 83.8 82.8 81.7 80.8 79.9 79.0 78.0 8580 7960 7380 6850 6350 5880 5440 5040 4660 4320 4000 3670 3400 3150 2930 90.0 89.8 87.6 86.5 85.5 84.2 83.1 82.0 80.9 80.0 79.0 78.0 77.3 76.5 76.0 The Equivalent Length Values used and included in calculating this table are: Diffuser and Boot -- 100 ft; Plenum Takeoff = 20 ft; Each Elbow = 14 ft. For each additional 14 ft equivalent length of boot and diffuser count one additional elbow. All cfm values are based on standard air. wall in each room or area of building, and locate them preferably beneath window areas. For residential installations limit each diffuser to a maximum of 7,000 Btuh. 4. Determine the required'Btuh delivery of each diffuser. Where more than one diffuser is used per room, proportion the heat loss equally among all diffusers. 5. Measure length and count number of elbows in each duct. From Table 4, deter mine the duct size (5 or 6-in. diameter) needed. Section A is for 5-in. duct, Section B is for 6-in. duct using sidewall or floor diffusers, and Section C is for 6-in. duct using baseboard diffusers. Perimeter Extended Plenum Systems in Crawl Space or Basement Con struction The considerations involved in the design of extended plenum systems are essentially the same as those of the individual pipe system. A simpli fied design procedure is summarized as follows: r 1- Calculate the heat loss of each room or area using the method explained in Chapter 12. Consider the basement or crawl space as a part of the structure and calculate its heat loss. Information in Manual 3 supplements* that contained in Chapter 12, particularly with respect to crawl space heat losses. buddDetermme reciu*re<^ furnace-bonnet capacity from the heat loss of the 3. Locate the diffusers on the plan. Allow at least one diffuser for each exposed wall in each room or area of building, and preferably beneath window areas. For residential installations limit each diffuser to a maximum of 7,000 Btuh. , _ Determine the required Btuh delivery of each diffuser. Where more than one "user is used per room, proportion the heat loss equally among all diffusers. 5. Measure the length of each duct and count number of elbows from the extended Se"UI5, to the diffuser. Note whether top or side plenum take-offs are to be used, /o *?. f "ole 5, determine the duct size needed. (Note: Use that section of Table 5 he used1) ^ ^ which applies both to the type of plenum take-off and diffuser to _ The cfm values in Table 5 are used with Table 6 for sizing the extended plenum y rem. No one extended plenum should exceed 35 ft in length.