The Lennox furnace pressure switch is a safety device that confirms proper airflow and draft before the furnace ignites. It monitors pressure changes created by the inducer motor and signals the control board to allow or stop ignition. If the switch does not close or open correctly, the furnace will not start or may shut down during operation. Problems usually occur due to clogged vent tubes, a faulty inducer motor, damaged wiring, or a defective switch diaphragm. The Lennox furnace pressure switch ensures safe combustion and proper venting of exhaust gases. Identifying these faults and fixing the exact cause helps restore normal furnace operation and prevents system failure. Table of Contents:What Does a Lennox Furnace Pressure Switch Do?Top Lennox Furnace Pressure Switch Problems You Shouldn’t IgnoreCommon Causes Behind Lennox Pressure Switch FailuresHow to Diagnose and Repair Lennox Furnace Pressure Switch Issues What Does a Lennox Furnace Pressure Switch Do? The Lennox furnace pressure...