OEM Lennox IMC Electric Heat Control Board — 91J88

The genuine OEM Lennox 91J88 IMC electric heat control board manages the sequencing and staging of your electric heat elements, coordinating the blower, heat relays, and safety limits to deliver safe, even warmth. This integrated module control (IMC) is the electronic brain of your Lennox electric heat section, monitoring inputs and switching high-current loads on demand.

A failing control board can produce a range of symptoms: no heat or intermittent heat, elements that fail to energize or won't shut off, a blower that runs continuously, blown fuses, or visible scorching and burnt connectors on the board itself. Diagnostic LEDs that flash fault codes or go dark are another common warning sign.

Using the OEM Lennox 91J88 guarantees the correct relay ratings, firmware, and connector pinout for your specific Lennox unit, so heat staging, safeties, and blower control all operate exactly as designed. Generic boards often lack the proper interlocks and can create unsafe conditions or nuisance faults. The factory board protects your equipment and preserves warranty compliance.