Air Compressor: Won't start
Check the electrical outlet for power. Reset the house circuit breaker if the electrical outlet is dead. If the electrical outlet works, shut off the compressor and bleed all the air from the tank. Flip the pressure switch control lever to the Auto position. If the pump starts when the tank is empty, then the check valve may be stuck open. The check valve prevents tank air from back flowing to the pump. A stuck-open check valve causes high pump head pressure, preventing the compressor from restarting. Test the check valve by allowing the compressor to fill the tank until the pump shuts off. Then pull the ring on the safety valve to bleed air out of the tank to reach the cut-in pressure, so the pressure switch attempts to restart the motor to refill the air tank. If the compressor won't start with air in tank, replace the check valve. If the compressor won't start with an empty air tank, replace the pressure switch if it isn't activating the pump motor. Replace the pump motor if it doesn't start when activated by the pressure switch.
Replace the air compressor pressure switch
The pressure switch turns the air compressor pump on and off to regulate tank air pressure. If the compressor isn't cycling on and off to fill the tank, replace the pressure switch.
Replace the air compressor check valve
The check valve prevents tank air from back flowing to the pump. A failed check valve will apply high air pressure to the head of the pump preventing the motor from restarting once the tank has filled. If the motor starts when the tank is empty of air but won't restart when the tank is full, replace the check valve.
Replace the air compressor pump motor
The pump motor spins the shaft that drives the compressor piston. Replace the pump motor if it doesn't run when activated.
You can replace a defective air compressor check valve in about 10 minutes.
If the air compressor won't fill the tank with compressed air, rebuild the pump using these steps in about 45 minutes.
Find out how to reduce air compressor noise.
Learn how to maintain an oil-less air compressor for safe and efficient operation.