7Gas connections
Connecting gas supply piping
1.Remove the top access panel and refer to FIG.’s
a.Install ground joint union for servicing, when required.
b.Install a manual shutoff valve in the gas supply piping outside boiler 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.
Figure 7-1 Gas Supply Piping - Model 399
UNION
GAS SUPPLY
Installation & Operation Manual
Figure 7-3 Gas Supply Piping - Models 600 - 800
MANUAL SHUTOFF VALVE (FACTORY SUPPLIED)
GAS SUPPLY
DRIP LEG
UNION
3.Support piping with hangers, not by the boiler or its accessories.
SEDIMENT TRAP / DRIP LEG 
MANUAL
WARNING
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 boiler or its accessories. Failure to comply could result in severe personal injury, death, or substantial property damage.
SHUTOFF VALVE (FIELD SUPPLIED)
Figure 7-2 Gas Supply Piping - Model 500
UNION
FIELD SUPPLIED
GAS SUPPLY
SEDIMENT TRAP / DRIP LEG 
MANUAL SHUTOFF VALVE (FACTORY SUPPLIED)
4.Purge all air from the gas supply piping.
5.Before placing the boiler in operation, check the boiler 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.
WARNING Do not check for gas leaks with an open flame – use the bubble test. Failure to use
the bubble test or check for gas leaks can cause severe personal injury, death, or substantial property damage.
6.Use pipe sealing compound compatible with propane gases. Apply sparingly only to male threads of the pipe joints so that pipe dope does not block gas flow.
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