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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 28066
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
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Why does my craftsman air compressor trip my circuit breaker

Customer Question

why does my craftsman air compressor trip my circuit breaker at the cut in pressure?
Submitted: 1 year ago.
Category: Small Engine
Expert:  urelectrician replied 1 year ago.

Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.

1) Take a look at the nameplate rating located on the compressor motor. What is the FLA (Full Load Current) rating of the motor. How many amps? What is the voltage and horsepower rating of the motor?

2) Did the compressor previously work OK prior to tripping the breaker or is this a new problem?

3) How many amps is the breaker? What size are the branch circuit conductors?

4) Does the breaker trip upon the motor start up or a few minutes after the compressor is running at full speed?

Customer: replied 1 year ago.
hello kevin, I am quite certain I don't need an electrician. The compressor has been working on the same 20 amp circuit since 1997. there has been no work done on the house recently and no new aplliances added. I need a tech who works on air compressors, sorry about the confusion but the web site didn't direct me very clearly.
Expert:  urelectrician replied 1 year ago.

No problem, I will opt out of the question then. Possibly another expert here can assist you.

Since it has been working correctly, I would suspect either warn out motor windings or a defective pressure switch. A defective pressure switch would be the 1st component I would check for.

No need to reply back to me. You will be notified when another expert picks up the question.


Expert:  Curtis B. replied 1 year ago.

Why din't you have both capacitors checked? One is start capacitor , other is the run capacitor. Likely the start capacitor is bad!

Expert:  Curtis B. replied 1 year ago.

Replace the start capacitor!

Expert:  Curtis B. replied 1 year ago.

I can call if you like , but a start capacitor would be cheaper!

Expert:  Curtis B. replied 1 year ago.


Customer: replied 1 year ago.
we can skip the call. I'll assume the start cap. is the one I didn't have checked. Is there some way to tell which is the start cap.?
Expert:  Curtis B. replied 1 year ago.

The capacitors are not identified in he Sears manuals, but electrical supply that sells capacitors can tell which is start, and which is run, they have different ratings.

Customer: replied 1 year ago.
OK thanks. I don't have alot of faith in the guy that checked the one, so I guess I'll do both if I can find them. Thanks.
Expert:  Curtis B. replied 1 year ago.

Thank you, ***** ***** to close.