OEM Lennox Pressure Switch with Bracket — 63K93

The Lennox 63K93 pressure switch with bracket is a critical safety device that confirms the draft inducer is producing adequate airflow before the furnace is permitted to ignite. It senses negative pressure created by the inducer motor and closes its contacts to signal the control board that venting is safe. If proper draft is not detected, the switch stays open and prevents ignition — protecting your home from unsafe combustion and flue-gas spillage. This assembly ships with the correct OEM mounting bracket for a bolt-in fit.

Common failure symptoms include a furnace that runs the inducer but never ignites, repeated safety lockouts, error codes indicating the pressure switch is stuck open or stuck closed, and short-cycling. Clogged hoses, a cracked diaphragm, or corroded contacts are typical causes of failure.

Why OEM matters: The 63K93 is set to a precise pressure trip point that matches the airflow of your specific Lennox furnace and inducer. Using a switch with the wrong set point can allow ignition under unsafe draft conditions or cause constant nuisance lockouts. The genuine Lennox part guarantees the exact calibration, terminal configuration, and bracket alignment your furnace was designed around, keeping the safety circuit accurate and reliable.