A/C compressor running non-stop

[mcburton3]

Hello all,

I have a classic A/C and heating system with an inside down-flow fan unit, furnace, and cooling coils, and an outside compressor/condenser unit. Just this week, I noticed that the compressor/condenser unit continues to run like it normally would when the A/C is on (i.e., the compressor and the condenser fan are running), but it runs non-stop, even when I have cooling turned off on the thermostat. When I pull the 110V plug on the inside fan unit, the compressor and condenser shut off, but as soon as I plug it in, they come back on.

I have seen this happen before some years ago in a different house after a thunderstorm and we had a recent thunderstorm here, but I can't remember what the problem was as how to fix it. Any ideas on what this might be? I thought it might be a relay on the inside fan unit but I pulled the only relay I could find without any luck -- turns out that relay is for the inside fan blower motor. Maybe I have a stuck relay on the outside unit?

Probably doesn't matter, but the system is a Rheem RAFD-036JAS.

Thank you in advance!

Matt

[d_griff]

Hello all,

I have a classic A/C and heating system with an inside down-flow fan unit, furnace, and cooling coils, and an outside compressor/condenser unit. Just this week, I noticed that the compressor/condenser unit continues to run like it normally would when the A/C is on (i.e., the compressor and the condenser fan are running), but it runs non-stop, even when I have cooling turned off on the thermostat. When I pull the 110V plug on the inside fan unit, the compressor and condenser shut off, but as soon as I plug it in, they come back on.

I have seen this happen before some years ago in a different house after a thunderstorm and we had a recent thunderstorm here, but I can't remember what the problem was as how to fix it. Any ideas on what this might be? I thought it might be a relay on the inside fan unit but I pulled the only relay I could find without any luck -- turns out that relay is for the inside fan blower motor. Maybe I have a stuck relay on the outside unit?

Probably doesn't matter, but the system is a Rheem RAFD-036JAS.

Thank you in advance!

Matt

explain what you mean when you pull the plug???
If you turn the stat off and the unit still runs it could be a bad stat. If the contactor outside was welded shut, It would not shut off when you killed power to the furnace inside, It would only shut off when you turned off the 220 to the condenser.
It most likely is a bad stat, shorted stat wire, or whatever powers the 24 volt to the condenser is shorted/bad. Call a pro!!!!!

[Shophound]

Many furnaces in California plug right into the wall. Here in my area they are all hard wired into a fused safety switch.

Yes, a pro can determine why the outdoor unit will not shut off whenever the furnace is plugged in. Hard to call it from here.

[mcburton3]

Thanks guys. It was my thermostat -- I didn't see that one coming. It was a new LuxPro thermostat I installed in the winter and it apparently has problems with cooling.

Regards,

Matt