OEM Lennox Ignition Control Module — 49W66

The genuine OEM Lennox 49W66 ignition control module is the brain that manages the ignition sequence and safety logic of your Lennox furnace. It coordinates the igniter, gas valve, flame sensor, and blower timing, monitoring each step to ensure a safe, reliable light-off every heating cycle. Manufactured to exact Lennox specifications, it delivers the precise voltage, timing, and flame-sensing thresholds your system depends on.

A failing ignition control module produces telltale symptoms: the furnace won't ignite or locks out after several attempts, the igniter never glows, the system short-cycles, or the unit ignites intermittently and drops out on the flame sensor. You may also see error codes flashed by the diagnostic LED or hear the blower run without any heat. Because this board governs gas ignition, faults here directly affect both comfort and safety.

Installing the OEM 49W66 is critical for Lennox equipment. The board's firmware, relay ratings, and safety interlocks are matched to your furnace's design. Substitute boards may not properly control flame sensing or timing, risking nuisance lockouts, unsafe operation, or damage to connected components. This factory-authorized module restores dependable, code-compliant ignition and protects your investment.