Resizethecommonventingsystemto theminimum ventpipesizedeterminedbyusingtheappropriate tablesin appendixG. (Thesearein thecurrentstan- dardsoftheNationalFuelGasCodeANSIZ223.1in theUSA,andtheappropriateCategory1NaturalGas
andPropaneappliancesventingsizingtablesin the currentstandardsof theCSAB149NaturalGasand
PropaneInstallationCodesinCanada.)
A,CAUTION
3 - The gas piping must not run in or through air ducts, clothes chutes, gas vents or chimneys, dumb waiters, or elevator shafts.
4 - The piping should be sloped 1/4 inch (6.4 mm) per 15 feet (4,57 m) upward toward the meter from the fur- nace. The piping must be supported at proper intervals [every 8 to 10 feet (2.44 to 3.01 m)] with suitable hang- ers or straps, Install a drip leg inside vertical pipe runs to the unit,
5 - In some localities, codes may require the installation of a manual main
A, IMPORTANT
Gas Supply
1 - This unit is shipped standard for left or right side instal- lation of gas piping (or top entry in horizontal applica- tions). Connect the gas supply to the piping assembly.
2 - When connecting the gas supply piping, consider fac- tors such as length of run, number of fittings, and fur- nace rating to avoid excessive pressure drop. Table 9 lists recommended pipe sizes for typical applications.
NOTE - Install a 1/8 inch NPT plugged tap in the field piping upstream of the gas supply connection to the unit. The tap must be accessible for test gauge connection. See figure 19. NQ TE - If emergency shutoff is necessarj4 shut off the main manual gas valve and disconnect main power to the fur- nace. The installer should properly label these devices.
TABLE 9
Gas Pipe Capacity - ft3/hr (m3/hr)
Nominal | Internal |
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| Length of Pipe |
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Iron Pipe |
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Diameter |
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Size | inches | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | 100 | |
inches | ||||||||||||
(mm) | (3.048) | (6.096) | (9.144) | (12.192) | (15.240) | (18.288) | (21.336) | (24.384) | (27.432) | (30.480) | ||
(ram) | ||||||||||||
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3/8 | .493 | 95 | 65 | 52 | 45 | 40 | 36 | 33 | 31 | 29 | 27 | |
(9.53) | (12.522) | (2.69) | (1.84) | (1.47) | (1.27) | (1.13) | (1.02) | (.73) | (.88) | (.82) | (.76) | |
1/2 | .622 | 175 | 120 | 97 | 82 | 73 | 66 | 61 | 57 | 53 | 5O | |
(12.7) | (17.799) | (4.96) | (3.40) | (2.75) | (2.32) | (2.07) | (1.87) | (1.73) | (1.61) | (1.50) | (1.42) | |
3/4 | .824 | 360 | 250 | 2OO | 170 | 151 | 138 | 125 | 118 | 11o | 103 | |
(19.05) | (20.930) | (10.19) | (7.08) | (5.66) | (4.81) | (4.28) | (3.91) | (3.54) | (3.34) | (3.11) | (2.92) | |
1 | 1.049 | 680 | 465 | 375 | 32O | 285 | 26O | 24O | 22O | 2O5 | 195 | |
(25.4) | (26.645) | (919.25) | (13.17) | (10.62) | (9.06) | (8.07) | (7.36) | (6.80) | (6.23) | (5.80) | (5.52) | |
1.380 | 1400 | 950 | 77O | 66O | 580 | 53O | 490 | 46O | 430 | 400 | ||
(31.75) | (35.052) | (39.64) | (26.90) | (21.80) | (18.69) | (16.42) | (15.Ol) | (13.87) | (13.03) | (12.18) | (11.33) | |
1.610 | 2100 | 460 | 1180 | 990 | 9OO | 81o | 75O | 690 | 65O | 62O | ||
(38.1) | (40.894) | (59.46) | (41.34) | (33.41) | (28.03) | (25.48) | (22.94) | (21.24) | (19.54) | (18.41) | (17.56) | |
2 | 2.067 | 3950 | 2750 | 2200 | 1900 | 1680 | 1520 | 1400 | 1300 | 1220 | 1150 | |
(50.8) | (52.502) | (111.85) | (77.87) | (62.30) | (53.80) | (47.57) | (43.04) | (39.64) | (36.81) | (34.55) | (32.56) | |
2 | 2.469 | 6300 | 4350 | 3520 | 3000 | 2650 | 2400 | 2250 | 2050 | 1950 | 1850 | |
(63.5) | (67.713) | (178.39) | (123.17) | (99.67) | (84.95 | (75.04) | (67.96) | (63.71) | (58.05) | (55.22) | (52.38) | |
3 | 3.068 | 11000 | 7700 | 6250 | 5300 | 4750 | 4300 | 3900 | 3700 | 3450 | 3250 | |
(76.2) | (77.927) | (311.48) | (218.03) | (176.98) | (150.07) | (134.50) | (121.76) | (110.43) | (104.77) | (97.69) | (92.03) | |
NOTE - Capacity given in cubic feet (In 3) of gas per hour and based on O.60 specific gravity gas.
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