Gas Piping - Crown Boiler AWR Series Installation Instructions Manual

• Shut off gas supply before servicing the boiler.
• All gas piping must be gas tight. Use thread compound that is listed for gas service on all threaded joints
to avoid leaks, which may result in fire or explosion.
• Size gas piping, regulators, valves and meters so as to provide an adequate gas flow and pressure to the
boiler during operation. Failure to do so may cause poor combustion, noise, injury or death.
1) Size gas piping - Design system to provide adequate gas supply to boiler. Consider these factors:
a) Allowable pressure drop from point of delivery to boiler. Maximum allowable system pressure is ½ psig. Actual point
of delivery pressure may be less; contact gas supplier for additional information. Minimum gas valve inlet pressure is
listed on rating label.
b) Maximum gas demand. Consider existing and expected future gas utilization equipment (i.e. water heater,
cooking equipment).
2) Connect boiler gas valve to gas supply system -
a) Use methods and materials in accordance with local plumbing codes and requirements of gas supplier. In absence of
such requirements, follow National Fuel Gas Code, ANSI Z223.1/NFPA 54.
b) Use thread compounds (pipe dope) resistant to action of liquefied petroleum gas.
c) Install sediment trap, ground-joint union and manual shut-off valve upstream of boiler gas control valve. See
Figure 8.1.
d) All above ground gas piping upstream from manual shut-off valve must be electrically continuous and bonded
to a grounding electrode. Do not use gas piping as grounding electrode. Refer to National Electrical Code, ANSI/
NFPA 70.
3) Pressure test - Boiler and its gas connection must be leak tested before placing boiler in operation.
a) Protect boiler gas control valve. For all testing over ½ psig, boiler and its individual shutoff valve must be
disconnected from gas supply piping. For testing at ½ psig or less, isolate boiler from gas supply piping by closing
boiler's individual manual shutoff valve.
b) Locate and address leaks using listed combustible gas detector, a non corrosive leak detection fluid or other
listed leak detection method. Do not use matches, candles, open flames, or other ignition source.
Explosion Hazard. Do not use matches, candles, open flames or other ignition source to check for leaks.
• If gas pressure in the building is above ½ psig (3.5 kPa), an additional gas pressure regulator is required.
Using one additional regulator for multiple gas appliances may result in unsafe boiler operation. The
additional regulator must be able to properly regulate gas pressure at the input of the smallest appliance.
If the regulator can not do this, two or more additional regulators are required. Consult regulator
manufacturer and/or local gas supplier for instructions and equipment ratings.
• If an additional regulator is used to reduce boiler inlet pressure below 1/2 psig (3.5 kPa) it must be at least
6 to 10 ft. upstream of the boiler.
• It is very important that the gas line is properly purged by the gas supplier or utility company.
VIII Gas Piping
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WARNING
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DANGER
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WARNING
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