# What is causing my contactor to spark constantly



## clocert (Oct 14, 2010)

Lose wire causes sparks, make sure the wire connector is clean and tight, and no rust. get new connectors if you can.


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## SeniorSitizen (Sep 10, 2012)

I just had a visit with my tech about this and his reply was:

That's called contractor chatter and it often means a bad safety switch. I would bypass all 24v safety switches to verify.


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## Joels84944 (May 20, 2014)

Uh...

And where would I find that?. Remember I am new at this....


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## beenthere (Oct 11, 2008)

Fairview said:


> I just had a visit with my tech about this and his reply was:
> 
> That's called contractor chatter and it often means a bad safety switch. I would bypass all 24v safety switches to verify.


Seldom find a bad safety causing contactor chatter.

Maybe a bad connection on the low voltage side. Or a low voltage wire is shorting out.


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## beenthere (Oct 11, 2008)

beenthere said:


> Seldom find a bad safety causing contactor chatter.
> 
> Maybe a bad connection on the low voltage side. Or a low voltage wire is shorting out.



PS: Is the contactor chattering, or just pulling in and out quickly, there is a difference.


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## Joels84944 (May 20, 2014)

Beenthere, 

The plunger was going in and out rapidly, and sparking at same time. What I found was that we used to have a circuit board connected that our old A/C guy disconnected 2 years ago. The board has been removed, but when the unit started acting up I opened the panel and saw an extra blue cable unplugged. So silly me I plugged it into the 24 volt side and that is what caused the problem with the sparking. 

Doh....... So I unplugged it and voila the a/c is back up and running cool........


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## beenthere (Oct 11, 2008)

Good to hear.


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