773-333

This Lennox Air Pressure Switch is a critical safety component designed for high-efficiency HVAC systems and commercial rooftop units. Functioning as an air proving switch, it monitors the differential pressure within the system to ensure that the draft inducer motor is creating proper airflow before allowing the heating cycle to ignite. With calibrated set points of 0.15" WC and 0.34" WC, this dual-range switch protects your furnace or air handler from operating under unsafe conditions, such as blocked vents, flue restrictions, or inducer motor failure. Replacing a faulty or sticking pressure switch is essential for restoring reliable heating performance and ensuring the long-term safety of your HVAC equipment.
Type: Air Pressure Switch
Size: Small
Application: Primarily used in gas-fired furnaces, air handlers, and commercial rooftop HVAC units to monitor venting pressure and ensure safe combustion cycles.
Specifications: Dual set points: 0.15" WC and 0.34" WC; Air proving functionality; Safety-interlock compatible.