Weil-McLain GOLD CGS-4E - Manual (Page 25)

Part number 550-110-282/1108
25
GOLD CGs-4E Gas-Fired Water Boiler — Boiler Manual
Gas piping
5
Table 4 Pipe capacity for 0.60 specific gravity natural gas
Gas
pipe
length
(feet)
Capacity of pipe for pipe size of:
(Capacity in 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
Natural Gas:
1. Refer to Table 4 for pipe length and diameter. Base
on rated boiler input (divide by 1,000 to obtain cubic
feet per hour).
Table 4 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, refer to ANSI Z223.1 (or 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: 3.50” w.c. at high fire
(0.90” w.c. at low fire while in low fire at start-
up)
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. at high fire
(3.50” w.c. at low fire while in low fire at start-
up)
Connecting gas supply piping to boiler
1. Remove jacket front panel and refer to Figure 14 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 appropri-
ate length of pipe 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 dur-
ing 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 detailed above can result
in severe personal injury, death or substantial property
damage.
Figure 14 Gas supply piping