GC9S96 Service Manual
SCHEDULED MAINTENANCE
29
4.
of seconds and below the Size of Test Dial (selected in step 3 and shown in Table 1) will be the Cubic Feet per Hour
(CFH).
1/4
cu/ft
1/2
cu/ft
1
cu/ft
2
cu/ft
5
cu/ft
1/4
cu/ft
1/2
cu/ft
1
cu/ft
2
cu/ft
5
cu/ft
10 90 180 360 720 1800 36 25 50 100 200 500
11 82 164 327 655 1636 37 -- -- 97 195 486
12 75 150 300 600 1500 38 23 47 95 189 474
13 69 138 277 555 1385 39 -- -- 92 185 462
14 64 129 257 514 1286 40 22 45 90 180 450
15 60 120 240 480 1200 41 -- -- -- 176 439
16 56 113 225 450 1125 42 21 43 86 172 429
17 53 106 212 424 1059 43 -- -- -- 167 419
18 50 100 200 400 1000 44 -- 41 82 164 409
19 47 95 189 379 947 45 20 40 80 160 400
20 45 90 180 360 900 46 -- -- 78 157 391
21 43 86 171 343 857 47 19 38 76 153 383
22 41 82 164 327 818 48 -- -- 75 150 375
23 39 78 157 313 783 49 -- -- -- 147 367
24 37 75 150 300 750 50 18 36 72 144 360
25 36 72 144 288 720 51 -- -- -- 141 355
26 34 69 138 277 692 52 -- -- 69 138 346
27 33 67 133 265 667 53 17 34 -- 136 340
28 32 64 129 257 643 54 -- -- 67 133 333
29 31 62 124 248 621 55 -- -- -- 131 327
30 30 60 120 240 600 56 16 32 64 129 321
31 -- -- 116 232 581 57 -- -- -- 126 316
32 28 56 113 225 563 58 -- 31 62 124 310
33 -- -- 109 218 545 59 -- -- -- 122 305
34 26 53 106 212 529 60 15 30 60 120 300
35 -- -- 103 206 514
GAS RATE -- CUBIC FEET PER HOUR
Seconds fo
r
One
Revolution
Size of Test Dial
Seconds fo
r
One
Revolution
Size of Test Dial
Locate 40 seconds for one
revoluon in the chart below
Then locate the 1 cu dial column and select the
corresponding CFH from the 40 seconds for one revoluon row
TABLE 2
5. Use this formula to verify the Cubic Feet per Hour (CFH) input determined in step 4 is correct:
(3600 x Gas Meter Dial Size) / Time (seconds) = Cubic Feet per Hour (CFH)
3600 is used as there are 60 seconds in
a minute and 60 minutes in an hour.
60x60=3600
6. Check with your local utility for actual BTU content (caloric value) of natural gas in the area (the average is 1025
BTU’s).
7. Use this formula to calculate the BTU/HR input (See BTU/HR Calculation Example):
8.
increase pressure and input, and upward (counterclockwise) to decrease pressure and input. A properly operating unit
must have the BTU per hour input and CFM of air, within the limits shown to prevent short cycling of the equipment. As
the external static pressure goes up, the temperature rise will also increase. Consult the proper tables for temperature
rise limitation.