Air Compressor: Won't start with a full air tank

If the compressor won't restart after it fills the air tank, the check valve is likely stuck open. The check valve prevents tank air from back flowing to the pump. The stuck-open check valve causes high pump head pressure, preventing the compressor from restarting. Test the check valve by shutting off the compressor and pulling the ring on the safety valve to bleed the air from the air tank until it's empty. Turn on the compressor to fill the air tank. 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 the tank, replace the check valve.

air compressor

These repairs may help solve your air compressor problem

Replace the air compressor check valve

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.

How to replace an air compressor check valve

If your air compressor won't restart after the tank fills, the check valve might be the problem. This DIY repair guide and video explain how to replace an air compressor check valve in less than 15 minutes.

Repair difficulty
Time required
 15 minutes or less
Read more

Symptoms common to all air compressors

Choose a symptom to see related air compressor repairs.

Main causes: lack of electrical power, check valve failure, bad pressure switch
Main causes: loose air tube fitting connections, bad check valve, faulty safety valve, damaged or corroded air tank, bad air pump
Main cause: bad air tank pressure gauge
Main cause: faulty output air pressure regulator
Main causes: bad safety valve, pressure switch failure
Main causes: tank drain valve open or leaking air, leaky air tank, bad safety valve, worn pump seals, bad pump valve plate
Main causes: rusted air tank, loose air tube fitting connections, bad check valve, leaky safety valve, bad tank drain valve

Repair guides common to all air compressors

These step-by-step repair guides will help you safely fix what’s broken on your air compressor.

How to replace an air compressor check valve

You can replace a defective air compressor check valve in about 10 minutes.

Repair difficulty
Time required
 15 minutes or less
May 1, 2015
By Lyle Weischwill
How to rebuild an air compressor pump

If the air compressor won't fill the tank with compressed air, rebuild the pump using these steps in about 45 minutes.

Repair difficulty
Time required
 45 minutes or less
How to replace an air compressor pressure switch

You can replace a broken air compressor pressure switch in about 45 minutes.

Repair difficulty
Time required
 45 minutes or less

Articles and videos common to all air compressors

Use the advice and tips in these articles and videos to get the most out of your air compressor.

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