My central a/c pump outside keeps running. what is wrong and how do I fix it.?

Question

Inside my house the air shuts off fine. Even if I shut the thermostat off the unit/compresser outside runs all the time.

Answer 1

Favorite Answer

There is a contactor (relay) inside the outdoor unit that is most likely "welded" closed or the wiring is wrong causing the contactor coil to be energized all the time.

Turn the power off to the outdoor unit (this is only if you can do stuff like this, dangeous if you aren't inclined) open the electrical panel on the condensing unit ( a few 1/4 screws) and take a look at the contactor. if the contactor is pulled in with no power applied then you will need to replace the contactor.

http://www.grainger.com/Grainger/wwg/itemDetailsRe...

Source(s): 20 years in trades

Answer 2

If the fan is turning on the A/C equipment outside that does not mean that the compressor motor is running also. If you are uncomfortable dealing with electricity you really should have a heating/cooling contractor take a look. You may inadvertently cost yourself big money if you do the wrong thing - not to mention the possible hazards to your health if Mr. Amp should grab onto you.

Answer 3

Check to make sure that your "fan" switch is in the "auto" position instead of on. Other than that, I'm not sure what it could be.

Answer 4

is it the fan or the entire unit running? most likeley the switch is simply stuck....it happens we see it all the time.

Answer 5

Are you sure its not just the fan running?Could be stuck fan relay.