021-885

This professional-grade low-pressure air proving switch is a critical safety component designed for HVAC systems and industrial heating units. Functioning as a draft inducer safety sensor, this switch monitors the pressure differential within the combustion blower or ventilation system. It ensures that the appliance is venting correctly and that there is adequate airflow before allowing the ignition sequence to begin. By accurately detecting pressure changes, this switch prevents the buildup of dangerous gases and protects the system from operating under hazardous conditions. It is an essential replacement part for restoring the reliable performance and safety of furnace and rooftop heating units.
Type: Air Pressure Switch
Size: Small
Dimensions: not specified × not specified × not specified
Application: Commonly used in forced-air furnaces, rooftop HVAC units, and commercial heating systems to prove inducer fan operation and vent integrity.
Specifications: Low pressure threshold; Open point: 0.25 in WC (25); Close point: 0.41 in WC (41); SPST or SPDT configuration typical for air-proving applications.