Cleveland Controls AFS-275-112 SPDT Adjustable Air Pressure Sensing Switch Range

The Cleveland Controls AFS-275-112 Dual Air Pressure Sensing Switch, SPDT Adjustable for several HVAC systems. This switch is programmable to calculate any variation in pressure within a given pressure range and produce an electrical signal. It works by using a diaphragm that changes with the pressure of the air. Whenever the air pressure is either higher or lower than the set point, the diaphragm bends and triggers the internal switch. This then includes closing or opening the electrical contacts to trigger a signal in the adjacent control system. It is found to be used in many different HVAC systems, such as air handlers, fan coil units, VAV boxes, and pneumatic controls.