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A common query I see across the internet is Campbell Hausfeld air compressor won’t start under load. This article will provide you will all the possible reasons as to why your Campbell Hausfeld air compressor won’t restart, along with existing reader questions and responses related to the issue.

To learn more about Campbell Hausfeld air compressors, visit our brand page here!

Table of Contents

Reasons Campbell Hausfeld Air Compressor Won’t Restart

If your Campbell Hausfeld air compressor won’t restart after it fills the air tank, the check valve is likely stuck open causing the air compressor not start under load. The check valve’s role is to prevent tank air from back-flowing towards the pump. The stuck-open check valve will cause high pump head pressure, preventing the compressor from being able to restart.

Follow these steps to test the check valve:

  1. Shut off the compressor and pull the ring on the safety valve to bleed the air from the air tank until it’s empty.
  2. Turn on the compressor to fill the air tank.
  3. 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.

Reasons Campbell Hausfeld Air Compressor Won’t Restart Tips

If the Campbell Hausfeld compressor won’t start with air in the tank, you must replace the check valve. If the check valve is not the issue, then it’s likely that it may be the unloader valve that is the component failing. To diagnose if the unloader valve is working properly, simply listen to the compressor closely as it reaches the cut-off pressure.

Just after the compressor stops running you should be able to hear a short sharp discharge of air from the unloader valve, which is usually located on the pressure switch itself.

If you don’t hear the unloader valve releasing pressure, this could be the cause of your air compressor not restarting when there’s pressure in the tank. Visit our Air Compressor Won’t Start Under Load guide for information!

Other possibilities include the motor being too hot and the thermal overload switch not allowing the compressor to restart until it’s cooled down, or even a faulty/weak start capacitor that has the capability to initially start the compressor but not restart the compressor.

Additional Troubleshooting Pages

Air Compressor Types Troubleshooting

Air Compressor Brand Specific Troubleshooting

Air Compressor Brand/Problem Specific Troubleshooting

Air Compressor Part Specific Troubleshooting

Reader Questions & Responses

Campbell Hausfeld Air Compressor Won’t Kick Back On – Campbell Hausfeld Air Compressor Troubleshooting

I have a Campbell Hausfeld air compressor 20 gallon, it builds air just fine but after I start using it the motor try’s to crank back up but barely turns over a few times then nothing.

I have to let the air out and wait a few minutes and start all over.

Smaller Campbell Hausfeld air compressor
Smaller Campbell Hausfeld air compressor

Response

Friend, I have uploaded an image of a new Campbell Hausfeld air compressor 20 gallon. If yours is different than the compressor shown, how about uploading a photo or three of yours?

The key thing you’ve written is “I have to let the air out and wait a few minutes and start all over.”

If you have to let the air out for the compressor for it to restart, that indicates that the compressor hasn’t got enough power from the motor to overcome the start procedure, or there is enough air trapped over the piston to increase the start load beyond the capability of the compressor motor.

This air compressor symptom is typically related to a problem with the unloader valve not working. The unloader’s job is to vent any air over the piston when the compressor stops, reducing the restart load.

Please empty the tank, start the compressor, and check the unloader valve operation, will you? If you aren’t sure what the unloader is, there’s a page on this site with complete details.

Or, the compressor start problem could be related to the compressor power supply.

If you are not using an extension cord or power bar, if the socket into which the compressor is plugged is working, if the amperage of the socket power is 20 amps (better than 15 for compressors), you’ve checked and the compressor the unloader valve works, then it’s time to look to the possibility of a failing start capacitor being the issue.

If you are not sure what the capacitor is and does, there’s a page on this site that describes it, and another that tells how to spec and buy a new one.


If you have any questions regarding Campbell Hausfeld air compressors not restarting, please leave a comment below, with a photo if applicable, so that someone can help you!