Lochinvar & A.O. Smith 100189283 Control R-407A or excessive vent pipe length

or excessive vent pipe length creating backpressure that exceeds the switch's operating range

preventing thermal shock and short-cycling

or performing an annual service on rear access doors and cleanout plates

this housing ensures a precise seal for the inducer motor and impeller wheel

The 3PNO (3 Pole Normally Open) configuration allows for simultaneous switching of three line-voltage legs

Lochinvar & A.O. Smith 100189283 Control R-407A or excessive vent pipe lengthThe Lochinvar & A. O. Smith 100189283 Control (Integrated FTX725) is a critical OEM boiler control board designed for high efficiency commercial hydronic systems. This integrated furnace control manages critical combustion sequences, including the hot surface igniter timing, blower speeds, and gas valve modulation. Engineered specifically for the Lochinvar Knight and high output A. O. Smith series, it serves as a direct replacement for legacy part