Description
The Lennox 14A54 2-Stage Pressure Switch 0.45/0.75″ WC senses airflow pressure changes in HVAC systems such as furnaces and air handling units. It uses a diaphragm that reacts to differential pressure, activating electrical contacts at two calibrated points. The switch is connected through tubing to the inducer or vent system and wired to the ignition circuit. It confirms adequate draft before ignition, prevents burner start under low airflow, and manages operational sequencing during heating cycles. The component improves safety response, supports accurate pressure monitoring, and regulates system operation during varying airflow conditions.
