Gas Piping - Weil-McLain WMB-155C Manual

W
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AquaBalance

20 Gas piping

Boilers are shipped ready to fire natural gas
ONLY. You must install the propane venturi
if the boiler will be connected to propane.
See page 12. Failure to comply could result in
severe personal injury, death or substantial
property damage.
Connecting gas supply piping
1. Remove jacket door and refer to Figure 56 to pipe gas to
boiler.
a. Place a pipe wrench on the gas line inside the jacket
when tightening the gas line assembly to the boiler gas
connection (item 1).
b. Install steel pipe fittings as shown in Figure 56. All pipe
fittings and gas cock are supplied by the installer.
c. In Canada — The gas shut-off valve (item 2) must be
identified by the installer.
2. Use pipe dope compatible with propane gases. Apply spar-
ingly 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 substan-
tial property damage.
3. Connect gas supply piping to the ½" NPT gas cock (item 2).
4. Support gas piping with hangers, not by boiler or its ac-
cessories.
5. Purge all air from gas supply piping.
6. Before placing boiler in operation, check boiler and its gas
connection for leaks.
a. During any pressure testing at less than 13" w.c., close
the gas shutoff valve and disconnect system gas piping.
At higher test pressures, disconnect boiler and gas valve
from gas supply piping.
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.
DO NOT adjust or attempt to measure gas valve
outlet pressure. The gas valve is factory-set for the
correct outlet pressure. This setting is suitable for
natural gas and propane. Attempting to alter or
measure the gas valve outlet pressure could result
in damage to the valve, causing potential severe
personal injury, death or substantial property
damage.
Flexible appliance gas connectors are NOT rec-
ommended.
44
M -
ALL OUNT GAS FIRED WATER BOILER
— C
OMBI Boiler Manual
Figure 56
1 Boiler gas supply connection, ½" NPT male
2 T-handle gas cock, ½" NPT
3 Nipple, ½" NPT
4 Unions, ½" NPT
5 Nipple, ½" NPT
6 Tee, ½" NPT
7 Nipple, ½" NPT x 6", for drip leg
8 Cap, ½" NPT
ing at boiler, using one wrench to prevent the
boiler gas line connection from turning. Failure
to support the boiler gas connection pipe to
prevent it from turning could damage gas line
components.
when tightening gas pip-
Part number 550-100-305/1016