Weil-McLain EG - Manual (Page 14)

Part Number 550-110-639/0703 14
EG, PEG, EGH G
AS
-
FIRED
B
OILERS
—
SERIES
4 — B
OILER
M
ANUAL
Gas piping
5
Connecting gas supply piping
Size gas piping considering :
a. Diameter and length of gas supplying piping.
b. Number of fittings.
c. Maximum gas consumption (including any possible
future expansion).
d. Allowable loss in gas pressure from gas meter outlet
to boiler. For pressure drops, see ANSI Z223.1.
Canadian installations must comply with CAN/CSA
B149.1 or .2 Installation Codes.
1. For natural gas:
a) Refer to following tables. To obtain cubic feet per hour,
divide the input by 1000.
b) Size for rated boiler input.
c) Inlet gas pressure:
5" W.C. minimum
13" W.C. maximum
d) Manifold gas pressure: 3 ¹⁄₂" W.C.
e) Install 100% lock-up gas pressure regulator in supply
line if inlet pressure exceeds 13" W.C. Adjust for 13"
W.C. maximum.
2. For propane gas:
a) Inlet gas pressure: 11" W.C. minimum
13" W.C. maximum
b) Manifold gas pressure: 10" WC.
c) Gas pressure regulator provided by gas supplier must be
adjusted for maximum pressure of 13" W.C.
d) Contact gas supplier to size pipes, tanks and regulator.
3. Remove knock-out disc from jacket panel which gas
supply is to be piped.
4. Follow good piping practices.
5. Pipe joint compound (pipe dope) must be resistant
to corrosive action of liquified petroleum gases. Apply
sparingly only to make threads of pipe joints.
6. Install drip leg at inlet of gas connection to boiler.
Where local utility requires, extend drip leg to floor.
7. Install ground joint union when required for
servicing. See Figure 22.
8. Install manual shut-off valve outside boiler jacket as
shown in Figure 22 when required by local codes.
9. Support piping by hangers, not by boiler or its
accessories.
10. In Canada only, the manual main shut off valve
(when used) must be identified by the installer.
11. Purge all air from piping.
12. Before placing boiler in operation, check boiler and
its gas connection for leaks.
Do not check for gas leaks with an open
flame - use bubble test. Failure to do so
can cause severe personal injury, death or
substantial property damage.
a) Close manual main shut-off valve during any pressure
testing at less than 13 inches water column.
b) Disconnect boiler and gas valve from gas supply piping
during any pressure test greater than 13 inches water
column.
Figure 22 Gas supply piping