Service manual

Installation & Operation Manual
42
7 Gas connections
Connecting gas supply piping
1. Remove the top access panel and refer to FIG.’s 7-1 thru 7-4
to pipe gas to the water heater.
a. Install ground joint union for servicing, when
required.
b. On Models 150 - 399 install a manual shutoff valve in
the gas supply piping outside water heater jacket when
required by local codes or utility requirements.
c. In Canada – When using manual main shutoff
valves, it must be identified by the installer.
2. Install sediment trap / drip leg.
SEDIMENT TRAP / DRIP LEG
Figure 7-1 Gas Supply Piping - Models 150 - 199
3. Support piping with hangers, not by the water heater or its
accessories.
SEDIMENT TRAP / DRIP LEG
Figure 7-2 Gas Supply Piping - Models 285 - 399
4. Purge all air from the gas supply piping.
5. Before placing the water heater in operation, check the
water heater and its gas connection for leaks.
a. The appliance must be disconnected from the gas
supply piping system during any pressure testing of
that system at a test pressure in excess of 1/2 PSIG
(3.5 kPa).
b. The appliance must be isolated from the gas supply
piping system by closing a manual shutoff valve
during any pressure testing of the gas supply piping
system at test pressures equal to or less than 1/2 PSIG
(3.5 kPa).
c. The appliance and its gas connection must be leak
tested before placing it in operation.
The gas valve and blower will not support
the weight of the piping. Do not attempt
to support the weight of the piping with
the water heater or its accessories. Failure
to comply could result in severe personal
injury, death, or substantial property
damage.
 WARNING
Figure 7-3 Gas Supply Piping - Model 500
UNION
GAS SUPPLY
DRIP LEG
MANUAL
SHUTOFF VALVE
(FACTORY SUPPLIED)
Figure 7-4 Gas Supply Piping - Models 600 - 800