new circuit panel w/ 40amp breaker for large a/c unit?

15 years ago

I just had a new circuit panel installed to replace the old Pacific. After it was installed and up and running, the electrician told me I have should have the a/c unit checked out because it was causing something(a breaker?) to get warm.

I called out a/c maintainance co., they came and cleaned up my unit, and told me the breaker was only 40amps. And since it says right on the a/c unit 44min and 70max amps, I don't have a large enough breaker for it on this new circuit panel. Which is why it is getting warm.

I told the electrician before this unit was installed that I have a very large a/c unit(8tons)and since they told me I needed some maintainance on it I know they were aware of the size. Also, before this circuit panel was installed I made it clear I needed them to do whatever was necessary to give us enough power.

Hope this all make sense, I know nothing about electic, but my question is; Should I be upset with this electric company about this issue, or is it so complicated that I should understand and just give them a chance to fix it???

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Comments (6)

joed
15 years ago
Call them and ask them to change the breaker. They might just do it. If they say they need to charge for it then you can plead your case for a discounted servie call or get upset as suits you.
If the old panel had a 40 amp then they may want charge as they replaced like for like.

Either way I don't think a breaker should be getting hot just because it is too small. If it was truelly too small it would be tripping.
texasredhead
15 years ago
To begin, you were wise to have the Federal Pacific panel replaced. What is the total amperage of the new service? It should be 200 amps which would give you plenty of space for the larger breaker.

IF, your electrician merly replaced the panel without upgrading the service you may have a problem depending on the service amperage. You should also have an outside shut-off at the compressor.

If your electrician is competitent, the A/c question should have been addressed at the time of the panel/service upgrade. Also, the size of the breaker does not effect the operation of the A/C unless the breaker trips when the unit comes on. What was the amperage of the breaker that handled the A/C on the old FP panel?
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terrier96
Original Author
15 years ago
Thanks for your quick responses.

The amperage on the old panel for the a/c WAS 40 amps, and it WAS tripping the breaker frequently, one of the reasons we knew we needed to get the circuit panel replaced. Also, because we knew the Federal Pacific was dangerous. The electrician knew we were throwing breakers and specifically knew we were throwing the a/c breaker. We talked about the a/c enough that seems like he should have known to do more about it than what he did.
The total amperage of the new service is 240amps. We did want them to upgrade it which they did.

He is coming back to change the breaker, but says the wire will only allow a 50 amp. The A/c man says it would be better to install the max, because when the unit gets older it will need that. The a/c man did clean out the unit which he says will make the fan cool it better and use less amps??

We will see if he tries to charge me to change it out.
bigbird_1
15 years ago
The total amperage would be 200A, not 240A. The 40A available from the subpanel is not added to the 200A, because the sub is fed by the 200A main panel.
normel
15 years ago
If the AC nameplate says min circuit ampacity is 44 and the max breaker is 70, then the wire the electrician says is good to 50A will be OK.
texasredhead
15 years ago
What gauge of wire does he say will handle a 50 amp breaker?

new circuit panel w/ 40amp breaker for large a/c unit?

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new circuit panel w/ 40amp breaker for large a/c unit?

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joed

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