Operating instructions

GW A Gas-Fired Water Boilers – Boiler Manual
13Part Number 550-101-010/0703
Figure 10 Gas supply piping
Table 5 Pipe capacity for 0.60 specific gravity natural gas
4 Install gas piping
Natural Gas:
1. See Table 5 for pipe length and diameter. Base on rated boiler
input (divide by 1,000 to obtain cubic feet per hour). Table 5 is
only for gas with specific gravity 0.60, with a pressure drop
through the gas piping of 0.30" w.c. For additional gas pipe sizing
information, see ANSI Z223.1 (B149.1 or B149.2 for Canadian
installations).
2. Inlet pressure required at gas valve inlet:
• Maximum: 13" w.c.
• Minimum: 5" w.c.
• Manifold gas pressure: 3.5" w.c.
3. Install 100% lockup gas pressure regulator in supply line if inlet
pressure exceeds 13" w.c. Adjust for 13" w.c. maximum.
Propane Gas:
1. Contact gas supplier to size pipes, tanks and 100% lockup gas
pressure regulator.
2. Adjust propane supply regulator provided by gas supplier for
13" w.c. maximum pressure.
3. Inlet pressure required at gas valve inlet:
• Maximum: 13" w.c.
• Minimum: 11" w.c.
• Manifold gas pressure: 10" w.c.
Gas pipe
length
(feet)
Capacity of pipe for pipe size of:
(
Capacity in standard cubic feet gas per hour )
½" ¾" 1" 1¼" 1½"
10 132 278 520 1050 1600
20 92 190 350 730 1100
30 73 152 285 590 860
40 63 130 245 500 760
50 56 115 215 440 670
75 45 93 175 360 545
100 38 79 150 305 460
150 31 64 120 250 380
1. Remove jacket front panel and see Figure 10 to pipe gas to
boiler.
a. Install drip leg at inlet of gas connection to boiler. Where
local utility requires drip leg to be extended to the floor, use
appropriate length of nipple between cap and tee.
b. Install ground joint union for servicing, when required.
c. Install manual shutoff valve in gas supply piping outside
boiler jacket when required by local codes or utility
requirements.
d. In Canada — When using manual main shutoff valve, it must
be identified by the installer.
2. Support piping with hangers, not by boiler or its accessories.
3. Purge all air from gas supply piping.
4. Before placing boiler in operation, check boiler and its gas
connection for leaks.
a. Close manual main shutoff valve during any pressure
testing at less than 13" w.c.
b. Disconnect boiler and gas valve from gas supply piping
during any pressure testing greater than 13" w.c.
Do not check for gas leaks with an open flame —
Use bubble test. Failure to use bubble test or check
for gas leaks can cause severe personal injury, death
or substantial property damage.
5. Use pipe dope compatible with propane gases. Apply sparingly
only to male threads of pipe joints so that pipe dope does not
block gas flow.
Failure to apply pipe dope as described in this manual
can result in severe personal injury, death or
substantial property damage.
Connecting gas supply piping to boiler