Description
The York S1-02436052009 STDT Air Pressure Switch is an essential safety control components used in gas furnace systems to check proper inducer airflow before ignition. It operates by sensing differential air pressure generated by the draft inducer motor and closes its circuit only when the required 0.63 inches of water column pressure is reached in HVAC systems. In light commercial furnaces, it is installed in the burner and venting assembly to confirm that combustion gases are being properly moved through the heat exchanger and flue system. The switch helps ensure safe ignition sequencing, avoiding burner operation if airflow or venting conditions are insufficient.
