Easy Installation: Standard 2-wire spade terminal connection for immediate field replacement

this model is specific to 24V on/off (two-position) applications

and A99 temperature sensors

It will not open if the inlet and outlet pressures are equalized or if the system pressure is below this threshold

the Lennox 25G43 is technically identical to the 25G4301 and can be used as a direct 1:1 replacement in all Lennox furnace and AC systems

Lochinvar & A.O. Smith 100109944 Ignition Board R-22 Easy Installation: Standard 2-wire spadeThe Lochinvar & A. O. Smith 100109944 Ignition Board is a critical OEM replacement part engineered for high performance commercial gas water heaters. Designed for precision ignition control, this integrated circuit manages the HSI (Hot Surface Ignition) sequence, ensuring consistent flame sensing and gas valve timing for specific BTN and BTR 500 series units. As a verified factory replacement board, it eliminates the timing issues and terminal