MACH® Series
Gas-Fired Boiler
Installation
21
Pipe Capacity for Natural Gas
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)
Nominal
Iron Pipe
Size
(Inches)
Internal
Diameter
(Inches)
90º Ell
(Feet)
Tee
(Feet)
20
40
60
80
100
150
200
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.
Some leak test solutions, including soap and water, may cause corrosion. These solutions should be rinsed-off with
water after testing.
3.7
B
OILER
W
ATER
P
IPING
3.7.1 Piping
Design
Water Flow in System/Pumping Requirements
See the charts below for proper water flow requirements. Incorrect flow may result in eventual damage or premature
boiler failure that may not be covered by warranty.
Proper flow rates may be achieved through a combination of primary and secondary flow loops. Multiple zones and
pumps may result in different flow rates at different times. Consideration must be given to all possible conditions and
their consequences. For minimum flow rates at other than maximum firing rate, see C2500 Variable Pumping (below)
Flow
20 °F
Δ
T
40 °F
Δ
T
Pressure Drop (ft)
at Max Flow
GPM 238
119
16