OEM Lennox Draft Inducer Motor — 18K77

The genuine OEM Lennox 18K77 draft inducer blower motor pulls combustion gases through the heat exchanger and pushes them out through the flue, establishing the safe venting airflow your furnace needs before ignition. Working alongside the pressure switch, it clears the heat exchanger of residual gases at the start of every cycle and maintains proper draft throughout the burn. As a direct factory replacement, the 18K77 is matched to the exact airflow and mounting specifications of your Lennox furnace.

Common Failure Symptoms

• No ignition because the pressure switch never proves airflow
• Loud grinding, humming, or rattling from the inducer housing
• Furnace locks out or short-cycles on startup
• Motor runs slowly, intermittently, or not at all

A failing inducer motor is a frequent cause of no-heat calls, since the furnace's safety logic will not allow the burners to fire without confirmed venting.

Why OEM Matters

The inducer must deliver the precise airflow the pressure switch expects and physically fit the burner assembly. Aftermarket motors can produce the wrong draft or mounting alignment, triggering lockouts. The OEM Lennox 18K77 ensures factory-correct performance, proper fit, and safe, reliable venting for your Lennox equipment.