A/C causing main circuit breaker to trip???

[marcusnigel]

I know I have a Coleman split system that's 10yrs old, but I don't have the model# as it's dark outside and the label is very difficult to read, but my question is more general.

Lately, the main circuit breaker has been tripping and I'm thinking it has something to do with the a/c. I noticed the panel box is very hot by the main breaker when it does trip. And when I turned it back on, I tried turning off the a/c breaker for a while, and the main breaker got cool again. When i turned the a/c back on, the main breaker starting getting warmer.

Is there any common cause for something like this from the a/c???

Thanks for your input!
Marcus

[Robert]

Hi,

This could be a sign that your a/c compressor is going out or is overworking.

If so, it will pull excessive amps and this increases the temp in the wires which trips the breaker.


At 10 years old and with the heat wave and drought across alot of the country, this is happening alot.


IF this is it, you may could get by and extend life of compressor with a start assist kit.

This may or may not help at all.

If it has one already, then if it is the compressor, it is on it's last breath.


Would need to get amp readings to know for sure.

Also, make sure condenser coils are clean:

http://www.mobilehomerepair.com/article ... ioner.html


May be good time to have a Tech check it out.


Take care and best wishes,
Robert

[marcusnigel]

Thank you for your help sir! From reading your other messages, that's what I was thinking. And also, since it is that old, I believe you said you believe in replacing the unit rather than messing with parts right?

Just a follow up question out of curiosity: I notice that it trips the main circuit and NOT the AC circuit. The main is 100, whereas the AC is 45. Shouldn't it be tripping the AC circuit breaker first???

Thanks again!
I know enough to be dangerous!
Marcus

[Robert]

Hi,

You're very welcome. As to what it trips, depends on how it was installed.

If correct, you should have a dedicated breaker at the service pole

that goes straight to a wall disconnect next to outside condenser.


THAT dedicated breaker is what would normally trip.

Now, it could be faulty and thus the MAIN breaker for entire service panel would trip.

The wall disconnect is not an overcurrent breaker and would not trip.


If it is the compressor and it is 10 years old, replace the condenser unit.

I recommend replacing entire unit if part is $500 or more and 10 years old or more.

Now, due to age and the fact that 10 Seer units are not made anymore, the inside a-coil would need to be replaced as well.

I'd go with a 13 Seer condenser and a-coil.


Take care and best wishes,
Robert