Overheated AC disconnect

[Ron A. Bishop]

Hi guys...I am new to this post. Attached is a pic of an overheated AC disconnect. What would cause that? Should a breaker have tripped before this overheating occured? Can an AC unit be run if the air handler is off at the breaker?

[mnahrgang]

The breaker in the panel may have been over fused. There should have been a maximum amperage listed on the label.

Obviously there has been a problem that needs to be addressed by a specialist. AND if the unit is functioning, it should be turned off at the breaker until it is fixed.

[Robert Ernst]

That's a great pic. I looked it up and it said it was rated for 60 amps. How big was the breaker? I would guess it wasn't an issue of over current but and issue of a loose connection inside the disconnect that caused it to heat up.

[Frank P. Newman]

Likely the plug was not properly or completely inserted resulting in the overheat failure. The rating of the device or the upstream breaker is probably not an issue; however, if the compressor locked up and the breaker feeding it did not trip, the result could be the same - not the situation if the unit was found to be running.

[Chuck Evans]

That's a good one. That's the kind of thing that a buyer would never notice until it was too late.

[David A. Andersen]

Can an AC unit be run if the air handler is off at the breaker?

No.

The low voltage control comes from there.

They are not on the same circuit though! Outside is still hot!