Make sure that you are operating your air compressor safely & efficiently by understanding the basics of pressure switches. This guide gives you an overview.

Air compressor pressure switches control the flow of compressed air from the compressor to various uses, ultimately protecting your air compressor from damage by over-pressurizing. Understanding how these switches work and using them correctly can help ensure that your compressor is operating safely and efficiently.

How does a pressure switch work?

A pressure switch helps to regulate the amount of environment-altering pressure in an air compressor tank. Pressure is determined by a pre-set cut-in, wherein when the pressure drops below a certain set point the switch will open, allowing the motor to come on and begin recharging the tank with air. The cut-off happens when a maximum pressure (previously set) is reached inside the tank and the switch closes, causing the motor to turn off.

If your air compressor fills up to pressure but struggles to restart or the unloader valve on the pressure switch continues to release air, your check valve is likely the cause. You can run a quick test by running the compressor up to full pressure, once it shuts down disconnect the power to the unit. Loosen the nut on the air exhaust tube at the pump head...there should be no air present. If you have air present, the check valve is bad and needs to be replaced.