Supco NS2000031 Universal Air Pressure Switch Low cost, high accuracy and reliable universal air pressure switch that replaces many small foot print type switches. Features / Benefits Senses positive, negative or differential air pressure. Set Point Range: 0.01" to 10" w.c. Electrical Ratings: 1/10 hp @ 120 to 277 VAC. 28 VA pilot duty @ 24 VAC, 125 VA pilot duty @ 120 VAC. Contact Arrangement: SPDT Operating Temperature Range: 40F (4.4C) to 190F (87.8C). UL CSA Approved. 2-year warranty Common HVAC R Applications On gas fired warm air furnaces, prove fan flow by sensing draft down from blower; switch actuation allows ignition start up or shuts system down upon insufficient draft. Electronic air cleaners and humidifiers can employ sensing switches to prove airflow; switch actuation starts unit with sufficient airflow or draft. Strip heaters employ airflow sensing switches to prove positive pressure/airflow in duct and air movement across heat source; shuts off heat source with insufficient airflow. Exhaust fans and draft hoods employ sensing switches to sense draft down from exhaust fan; switch actuation signals condition upon fan failure or insufficient draft. Refrigeration and cooling coils are maintained by sensing differential pressure/airflow drop across coils; switch actuation signals condition when they ice, or actuates the defrost cycle. http://www.unicontrolinc.com/CC%20PDFs/LITNS2-11.pdf Powered by Turbo Lister The free listing tool. List your items fast and easy and manage your active items.