OEM Lennox Integrated Furnace Control Board — 46M99

The genuine OEM Lennox 46M99 integrated furnace control board is the electronic brain of your Lennox gas furnace. It manages the ignition sequence, monitors safety limits, and coordinates the timing of the inducer, igniter, gas valve, and blower motor to deliver safe, reliable heating. This board is engineered to the exact specifications of Lennox furnace platforms for a true plug-and-play fit.

Common failure symptoms: When the 46M99 fails you may see no ignition, a furnace that runs then shuts down on a fault, an inducer or blower that won't start, error codes flashing on the diagnostic LED, or intermittent no-heat calls. Scorch marks, cracked relays, or corroded traces on the board are also telltale signs of a board that needs replacement.

Why OEM matters: Aftermarket boards often use substitute relays and firmware that can mis-time the ignition sequence or trip Lennox safety circuits, leading to nuisance lockouts or unsafe operation. The factory-original 46M99 guarantees correct terminal pinouts, ignition timing, and safety-limit logic so your Lennox furnace performs to its rated efficiency and warranty specifications.