Nortek iHybrid DF6SF Series, Installation Instructions Manual

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GAS FLOW RATES (CUBIC FEET PER HOUR)
TIME FOR
ONE REVOLUTION
(SECONDS)
CUBIC FEET PER REVOLUTION
OF GAS METER
TIME FOR
ONE REVOLUTION
(SECONDS)
CUBIC FEET PER REVOLUTION
OF GAS METER
1 5 10 1 5 10
10 360 1,800 3,600 66 55 273 545
12 300 1,500 3,000 68 53 265 529
14 257 1,286 2,571 70 51 257 514
16 225 1,125 2,250 72 50 250 500
18 200 1,000 2,000 74 49 243 486
20 180 900 1,800 76 47 237 474
22 164 818 1,636 78 46 231 462
24 150 750 1,500 80 45 225 450
26 138 692 1,385 82 44 220 439
28 129 643 1,286 84 43 214 429
30 120 600 1,200 86 42 209 419
32 113 563 1,125 88 41 205 409
34 106 529 1,059 90 40 200 400
36 100 500 1,000 92 39 196 391
38 95 474 947 94 38 191 383
40 90 450 900 96 38 188 375
42 86 429 857 98 37 184 367
44 82 409 818 100 36 180 360
46 78 391 783 102 35 176 353
48 75 375 750 104 35 173 346
50 72 360 720 106 34 170 340
52 69 346 692 108 33 167 333
54 67 333 667 110 33 164 327
56 64 321 643 112 32 161 321
58 62 310 621 114 32 158 316
60 60 300 600 116 31 155 310
62 58 290 581 118 31 153 305
64 56 281 563 120 30 150 300
Table 14. Gas Flow Rates
CAPACITY OF BLACK IRON GAS PIPE (CU. FT. PER HOUR)
FOR NATURAL GAS (SPECIFIC GRAVITY - 0.60)
NOMINAL BLACK
IRON PIPE
DIAMETER (IN.)
LENGTH OF PIPE RUN (FT)
10 20 30 40 50 60 70 80
1/2 130 90 75 65 55 50 45 40
3/4 280 190 150 130 115 105 95 90
1 520 350 285 245 215 195 180 170
1 1/4 1,050 730 590 500 440 400 370 350
1 1/2 1,600 1,100 890 760 670 610
NOTES
The cubic feet per hour listed above must be greater than the cubic feet per hour of gas flow required by the equipment.
To determine the required cubic feet per hour of gas flow, divide the input rate of the unit by the heating value (from gas
supplier) of the gas.
Cubic Feet Per Hour Required =
Input To Furnace (Btu/hr)
Heating Value of Gas (Btu/Cu. Ft.)
Table 13. Black Iron Gas Pipe Capacities
GAS INFORMATION