Harsco Industrial C750, Installation & Owner'S Manual, Page: 25 / 58

MACH
®
Gas Fired Boiler
25
Gas Piping Schematic (left)
Install a sediment trap (drip leg) and a union
connection ahead of the primary manual shutoff
valve on the boiler. Gas piping should be installed
in accordance with National Fuel Gas Code, ANSI
Z223.1, latest edition, and any other local codes
which may apply; in Canada see CAN/CSA-
B.149.1, latest edition. In the Commonwealth of
Massachusetts, the gas cock must be a “T-handle
type.”
NOTICE! See Pipe Capacity for Natural Gas chart below for required pipe size, based on overall length of pipe
from meter plus equivalent length of all fittings. Approximate sizing may be based on 1 cubic foot of natural gas per
1,000 Btu per hour input, i.e., 500,000 Btu per hour requires about 500 cubic feet per hour. (See "Typical Boiler
Operating Conditions," Section 4.3, for more information.)
Pipe Capacity for Natural Gas
Nominal
Iron Pipe
Size
(Inches)
Internal
Diameter
(Inches)
Equivalent Pipe
Length
Maximum Capacity in Cubic Feet of Natural Gas per Hour
Pressure Drop of 0.5 inch Water Column/Equivalent Length of
Pipe (in feet)
90º Ell
(Feet)
Tee
(Feet) 20 40 60 80 100 150 200
1/2 0.622 1.55 3.1 120 82 66 57 50 40 35
3/4 0.824 2.06 4.12 250 170 138 118 103 84 72
1 1.049 2.62 5.24 465 320 260 220 195 160 135
1- 1/4 1.380 3.45 6.9 950 660 530 460 400 325 280
1- 1/2 1.610 4.02 8.04 1460 990 810 690 620 500 430
2 2.067 5.17 10.3 2750 1900 1520 1300 1150 950 800
2- 1/2 2.469 6.16 12.3 4350 3000 2400 2050 1850 1500 1280
3 3.068 7.67 15.3 7700 5300 4300 3700 3250 2650 2280
4 4.026 10.1 20.2 15800 10900 8800 7500 6700 5500 4600
3.6.1 Gas Supply Piping by Installer
The boiler and all gas piping connections should be pressure-tested and must be checked for leaks before being
placed into service. Test with compressed air or inert gas if possible.
The boiler must be disconnected at the boiler manual shut-off valve (located at the end of the supplied gas train)
from the gas supply piping system during any pressure testing of the system at pressures in excess of 1/2 psig (14"
W.C.).
During any pressure testing of the gas supply piping system at pressures equal to or less than 1/2 psig (14" W.C.), the
boiler should be isolated from the gas supply piping system by closing the manual shut-off.
Boiler Main Gas
Valve
Gas
Supply
Union
Drip Leg
Remote Gas
Shutoff
Field Supplied Piping