773-030

This premium 2-stage air pressure switch is a critical safety component designed for high-efficiency Lennox gas furnaces and HVAC systems. As an essential air-proving switch, it monitors the negative pressure generated by the draft inducer motor to ensure that combustion gases are being safely and effectively vented out of the heat exchanger. By detecting specific vacuum thresholds—calibrated to -0.85" WC and -0.50" WC—this dual-stage sensor ensures the heating system only proceeds with ignition when proper airflow is confirmed. This part is a common solution for furnaces experiencing ignition failure, short cycling, or error codes related to pressure differentials. Built for durability and precise response, it maintains the safety and efficiency of residential heating equipment during both low and high-heat cycles.
Type: Air Pressure Switch
Size: Small
Application: Used in dual-stage residential gas furnaces and heating units to verify proper venting and inducer motor operation.
Specifications: Dual-stage configuration; Low-stage setpoint: -0.50" WC; High-stage setpoint: -0.85" WC; vacuum-actuated safety sensor.