T-state white-rodgers 1f58w-77, after temp reached the outside compressor keeps running.
might be a relay to compressor I'm thinking or t-state not disconnecting. unit ac/heat pump Rheem. I shut down air handler from breaker, but the outside ac compressor still runs unless I power it off also from the breaker. Unit is 10 years no problem until now. what might it be? Thanks

I believe the contactor is stuck/defective in the outside unit.

Contacts are probably welded shut causing the unit to run without a signal from the thermostat.

It is not your thermostat.

[QUOTE=hvac1000]I believe the contactor is stuck/defective in the outside unit.

Contacts are probably welded shut causing the unit to run without a signal from the thermostat.

It is not your thermostat.[/QUOTE thanks for your time to answer my question. earlier this morning I removed the contact and seen it closed. cleaned it, but need new one. later I seen your answer. you are correct. thank you again for your help. http://www.askmehelpdesk.com/images/smilies/smile.gif
:)

Glad you got it working.