Window AC Compressor won't shut off

I had a bad double capacitor do that to me once on a full size split system. The power for the fan was backfeeding through the capacitor to the compressor.

Need to look at the circuit and start checking things out with a meter. Often the circuit diagram is inside the housing somewhere.

Sounds like the thermostat is stuck. Or, more correctly, the electrical contacts within the thermostat.

OK thanks, But would I still hear a "click" when I turn it (the thermostat) from low to high? Thanks, Tony

Yes. The click is the coil pulling the relay armature down, but the contacts could still be stuck solid. Try a new relay, and odds are your problem could be gone.

Joe

I cant recall seeing a thermostat labeled Low and High. Usually those are fan speed settings. Does the low and high knob you are turning have some extra travel in between the low and high or does it just click from low to high?

No sorry, it don't really say High and low, It is actually labeled

Thanks, Tony

Ok that makes sense. If you gave the capacity in BTU/hr and the voltage it might help. If you actually hear contacts clicking and not just some of the mechanics inside the thermostat clicking there might be a stuck relay. I've seen welded shut contactor points on residential compressors so it's possible on a window unit if equipped with a contactor aka relay.

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A good appliance parts store like we have nearby in the Chicago suburbs can probably cross-match the thermostat to another one. Where are you located?

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I am Near Wheeling WV. We have a Appliance connection (the name of it) in town I will check with to try to get the best price. Repair Clinic .com has it for $45.00 plus shipping. Thanks, Tony

Yes, very possible. You could dissemble, and check for continuity at the stat, and then rotate the knob. See if continuity makes and breaks.

Stat itself; no relay. Access from front.

Yeah Good call Christopher, looks like thats what it is, see my post above with the pictures.

Thanks. Nice to hear a kind word, once in a while. I got your picture, but not sure what it was, or what was going on, in the pic. No big loss.

Glad it worked out well, for you.

This is a 220V unit. Do you know If I could swap out the one from a 110V unit I am not using , As long as there are only 2 connections going to it,till I get the new one ordered. I have to get it on line, as no one local carries it. The old T-Stat does say on it;120/277 VAC. Have not looked at the one in the 110V unit yet. Thanks, Tony

Well Maybe I better not!? The 220 Volt unit states;

Thanks, Tony

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I ordered the T-Stat today from repair clinic.com,and it will be here tomorrow they said. That is quick! I just put the 110 volt T-Stat back in the 110 Volt unit and put it in another window for now. It's nowhere as powerful as the 220 unit, But I can cool the room with the 220 Volt unit (T-Stat jumped out) and use the little one to maintain the temperature.

Question; There is a large capacitor in the 220 V unit, after I unplug the unit, can I just short the capacitor leads to the case one at at time, or do I need to use some type of shunt, like a light bulb. Thanks, Tony

Most likely, it will work. Can't guarantee the 110 volt stat is safe with 220 volt power.