Model DFS-448-112 Air Pressure Sensing Switch is a proving switch designed for duct heater, oven, and other HVAC or Energy Management applications where an open-mounted, nonadjustable switch is needed. It is especially suitable for surface-mounting in areas where internal access is limited. Model DFS-448-112 can be used to sense positive, negative, or differential air pressure.

The plated housing contains a diaphragm and a snap-acting SPDT switch. The DFS-448-112 is equipped with convenient dual-barbed sample line connectors lo- cated on each side of the diaphragm. The dual-barbed connectors accept 3⁄16″ or 1⁄4″ ID flexible tubing.

The electrical connection consists of 1⁄4″ 90o quick connect spade terminals. The SPDT snap action switch operates on pressure rise of 0.05 ± 0.02″ wc. For additional application and technical information, please contact the sales office.