Gas Piping; Connecting Gas Supply Piping - Weil-McLain Evergreen 220 User Manual

™ GAS

Gas piping

Evergreen
TM
natural gas ONLY. You must install the propane ven-
turi if the boiler will be connected to propane. See
page 12. Failure to comply could result in severe per-
sonal injury, death or substantial property damage.
See page 16 for gas line sizing information.

Connecting gas supply piping

1. Refer to Figure 60 to pipe gas to boiler.
a. Place a wrench on the gas line when tightening the gas line
assembly to the boiler gas connection (item 1).
b. Install steel pipe fittings and factory-supplied gas cock as shown
in Figure 60. All pipe fittings are supplied by the installer. The
gas cock is shipped loose with the boiler.
c. In Canada — The gas shut-off valve (item 2) must be identi-
fied by the installer.
2. 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.
3. Connect gas supply piping to the 3/4" NPT gas cock (item 2).
4. Support gas piping with hangers, not by boiler or its accessories.
5. Purge all air from gas supply piping.
6. Before placing boiler in operation, check boiler and its gas con-
nection for leaks.
a. During any pressure testing at less than 14" (356 mm) 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.
b. After placing the boiler in operation, the ignition system safety
shutoff device must be tested, page 89.
7. Install 100% lockup gas pressure regulator in supply line if inlet
pressure can exceed 14" (356 mm) w.c. at any time. Adjust lockup
regulator for 14" (356 mm) w.c. maximum.
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 substan-
tial property damage.
DO NOT adjust or attempt to measure gas valve outlet
pressure. The gas valve is factory-set for the correct out-
let 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, caus-
ing potential severe personal injury, death or substantial
property damage.
1. See Figure 85, page 89 for location of the gas inlet pressure test port.
Part number 550-100-131/0715
-
FIRED WATER BOILER
boilers are shipped ready to fire
— Boiler Manual
Connect gas supply piping
1 Boiler gas supply connection, ¾" NPT male.
2 T-handle gas cock, ¾" NPT, shipped loose with boiler.
3 Nipple, ¾" NPT
4 Union, ¾" NPT
5 Nipple, ¾" NPT
6 Tee, ¾" NPT
7 Nipple, ¾" NPT x 4", for drip leg
8 Cap, ¾" NPT
piping at boiler, using one wrench to pre-
vent the boiler gas line connection from
turning. Failure to support the boiler gas
connection pipe to prevent it from turn-
ing could damage gas line components.
2. For natural gas or propane, the pressure required at gas
valve inlet pressure port (verify minimum gas pressure
when all gas appliances are in operation):
a. Maximum: 14" (356 mm) w.c. with no flow
(lockup) or with boiler on.
b. Minimum gas pressure, with gas flowing (verify
during boiler startup, while boiler is at high fire)
3½" (89 mm) w.c.
when tightening gas
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