Air conditioner will not stop

[bellco]

We have a new Goodman furnace,an older Fedders central air unit, and a Honeywell thermostat. Our air conditioning unit--both compressor and fan will not stop running once the thermostat reaches the desired temperature. We usually keep the t'stat set on 72. The fan is set to Auto. This morning when I got up the room temperature was 62. The unit had run nonstop all night. The only way we can get the unit to stop is to turn the switch to Off on the t'stat. Any ideas?

[bgrich2003]

something is wrong with your thermostat, wires, circuit board, or contactor
you should call a service tech

[markj]

Is it a round honeywell?
Common problem, have the stat replaced.

[imperix]

100% agreed have stat replaced

[dave82323]

wanna buy a t-stat LOL

[dougfamous]

I doubt it's a wire short if it stops when you switch it to off. Sounds like you need a new thermostat. I wouldn't do it yourself, have your contractor come out and swap it, and test everything at the same time to make sure nothing else is bad.

[amd]

If you don't have a heatpump or anything which requires more than four wires, replacing a t-stat can be a DIY task. (I know I’ll get flamed for this)

I'm not going to post any DIY instructions of obvious reasons, but whatever you do, turn the power off first to avoid shorting anything out.

It's your choice; many members here go overboard and think that a homeowner shouldn't even change a filter if it happens to be in the blower compartment.

[irishfan#1]

amd is right but you still may want to call a service tech out just to make sure ther is'nt any other problems.

[core]

Originally posted by bgrich2003
something is wrong with your thermostat, wires, circuit board, or contactor
you should call a service tech

This is the most intelligent answer and best advice here. I suggest you follow it.

Core

[jdb52]

I recently changed out my thermostat. Simple 4-wire project. All electic AC/Heat. But, I knew beyond doubt that my problem was the thermostat. Had I not known that, I would have called my HVAC company.

good luck,
jdb

[smokin68]

Originally posted by amd


It's your choice; many members here go overboard and think that a homeowner shouldn't even change a filter if it happens to be in the blower compartment.

Many members here think of homeowners safety first, which is why I wouldn't advise changing a filter in a compartment that contains line voltage.Alot of homeowners don't have a clue as to what can hurt them. Remember this.

[smokin68]

Originally posted by jdb52
I recently changed out my thermostat. Simple 4-wire project. All electic AC/Heat. But, I knew beyond doubt that my problem was the thermostat. Had I not known that, I would have called my HVAC company.

good luck,
jdb

Here's a classic example. JDB was successful. That's good. What if that t-stat was a old line voltage one, and homeowner doesn't know the difference. Homeowner badly hurt/dead, great internet advise to blame.

[jdb52]

Smokin 68,

You wrote:
Here's a classic example. JDB was successful. That's good. What if that t-stat was a old line voltage one, and homeowner doesn't know the difference. Homeowner badly hurt/dead, great internet advise to blame.


I understand the resistance to DIY information on this site. When I changed my stat, I researched it and got advice from another site, and frankly, I was surprised that such information and willingness to help was available given understandable liability concerns. But, the final responsibility for these kinds of decisions are with us, homeowners. If something bad happens, we are to blame, not you or any internet advice. I know that not everyone would see it that way.

If I was in your shoes, I wouldn't give DIY advice either.


jdb