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Gas-fired water boiler

Conversion Instructions Natural to Propane Gas

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-155	155-LP
Ultra-230	230-LP

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 Weil-McLain instructions and all codes and requirements of the authority having jurisdiction. The qualified agency performing this work assumes responsibility for this conversion.

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 start-up per Boiler Manual).

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.

Part number 550-141-951/1002

550-141-951/1002 specifications

The Weil-McLain 550-141-951/1002 is a highly regarded heating solution ideal for residential and commercial applications. Known for its efficient performance and robust design, this boiler is a reliable choice for those seeking effective temperature regulation and heating solutions.

One of the standout features of the Weil-McLain 550-141-951/1002 is its high-efficiency rating. The unit is designed to convert a significant amount of fuel energy into usable heat, minimizing waste and maximizing energy savings. This efficiency is further enhanced by advanced technologies that optimize the combustion process.

Built from high-quality materials, the Weil-McLain boiler boasts exceptional durability and longevity. Its corrosion-resistant heat exchanger enhances reliability while working under varying pressure levels. Moreover, its construction allows for excellent thermal conduction, ensuring rapid heating and reduced operational costs.

The 550-141-951/1002 features a user-friendly control panel, making it easy for homeowners and facility managers to adjust settings as needed. The integrated control system allows for precise temperature management, enabling users to achieve their desired comfort levels efficiently. In addition, this boiler is compatible with various heating systems, including hydronic and radiant heating applications.

Noise levels are often a concern with conventional boilers, but the Weil-McLain 550-141-951/1002 addresses this with its quiet operation. The design focuses on minimizing sound, creating a more pleasant environment for users.

Safety is paramount in the design of the Weil-McLain 550-141-951/1002. It comes equipped with multiple safety features, including pressure relief valves, automatic shut-off systems, and safety locks. These mechanisms work collectively to prevent accidents and ensure that the boiler operates within safe parameters.

Installation versatility is another strong point of the 550-141-951/1002. Its compact size allows it to fit into various spaces, making it suitable for both new constructions and retrofits in existing buildings.

In summary, the Weil-McLain 550-141-951/1002 stands out in the heating market due to its high efficiency, durability, user-friendly controls, quiet operation, and stringent safety features. This makes it a top choice for those looking for a dependable and effective heating solution, ensuring a warm, comfortable environment throughout the cold months.

Conversion Instructions Natural to Propane Gas