Gas-fired water boiler
Conversion Instructions Natural to Propane Gas
STOP! Read this notice
These instructions are only for propane conversion of a boiler that has already been installed. If you are converting a new boiler, not yet installed, do not use these instructions. Instead, read and follow all instructions in the Boiler Manual. Perform the propane conversion procedure on page 9 of the Boiler Manual only in the proper sequence.
These instructions are for conversion of the following boilers from natural gas to propane gas. (The propane gas orifice is located in the Propane Conversion Kit envelope.)
Boiler Model | Orifice stamping |
Ultra boilers are shipped ready to fire natural gas ONLY. You must install the propane orifice if the boiler will be connected to propane. Follow all instructions in this document and the Boiler Manual. Failure to comply could result in severe personal injury, death or substantial property damage.
This conversion must be installed by a qualified installer/service technician in accordance with the
Follow all instructions in proper order.
Do not tamper with orifice size. DO NOT change or modify orifice in any way.
Do not leave an uninstalled orifice in the building.
Verify the following before proceeding:
Propane gas operation requirements
Pipe sizing for propane gas
1.Contact propane gas supplier to size piping, tank and install a 100% lockup gas pressure regulator, or to verify size and condition of existing piping and equipment.
Propane supply pressure requirements
1.Adjust propane supply regulator provided by gas supplier for 13" w.c. maximum pressure.
2.Pressure required at gas valve inlet pressure port:
•Maximum: 13" w.c. with no flow (lockup) or with boiler on.
•Minimum: 4" w.c. with gas flowing (verify during boiler
3.After connecting propane gas line to boiler, and BEFORE operating, check gas pressure. If gas pressure is not in the range above, close manual gas valve and contact gas supplier to correct the problem before attempting to start or operate the boiler.
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