Lennox 38631 Transformer Freon and NF series—onto existing valve

and NF series—onto existing valve bodies manufactured before 1994

This kit is specifically engineered for mid-sized commercial systems where Buna-N compatibility with standard refrigerants and oils is required

Precise Factory Calibration: Pre-set at 0

Verification of the existing RJ-11 data cable integrity is recommended to ensure reliable signaling between the wall-mount controller and the rooftop power module

What is the difference between the A28AA-4 and the A28AA-4C

Lennox 38631 Transformer Freon and NF series—onto existing valveThe Lennox 38631 Transformer is a critical OEM replacement part designed for precise voltage regulation within residential and light commercial HVAC control systems. This heavy duty step down transformer features a 120V primary input and a 24V secondary output, providing a stable 30VA power rating required to energize high draw components such as furnace control boards, 24V thermostats, and ignition modules. Specifically engineered as a direct fit for