My blower and compressor are always running

[rajasethuraman]

Hello experts

I am facing a unique problem with my central air system.

Make of the system is Goodman.

For the past two months, my central air system\\s blower and compressor would not shut off when I place the thermostat to off position.

I called a specialist from Sears. He studied at my system for more than 2 hours and could not diagonize the problem. But he suggested to try changing the furnace circuit board.

I ordered a new circuit board and replaced it myself. Same problem. Blower / Compressor won't shut-off.

Then, I read in the internet that the cooling part of my thermostat might be broken. So, I changed my thermostat. Same problem continues. (my old thermostat was white-rodgers and my new one is Honeywell)

Now I am running out of options.

Please help me.

Thanks in advance.

Regards Raja

[Zyp]

I'd call another company! It sounds like a problem that can't be fixed here. Try alt.home.repair.

[Tony Hwang]

Hi, Your outdoor unit gets power when signal from thermostat calles for cooling. Y terminal from 'stat goes to 24V AC which goes to board on the air handler(inside unit-furnace) and then to out door unit. This 24V will pull main contactor which will supply power to compressor and fan. What happens if you turn off the breaker supplyng power to the unit? Since replacing 'stat won't do anything, probably the main contactor is stuck closed due to badly pitted contacts. Trouble-shooting is excercising logic step-by-step. Don't try to shot gun it wasting time and money. That Sears guy sounds like he does not know what he is talking about. What a shame!

[<kjpro]

You have many more options...

Change out the thermostat wiring. If that doesn&#39;t do it... Change the wiring to the outdoor unit. If that still doesn&#39;t resolve the issue... Change the transformer. Next would be the contactor. You still have the problem? Change out both run capacitors. That should just about cover everything.

Wait, one last thing... If you still have the problem after changing all of the above, you may need a new furnace.

If all else fails, maybe you should call a competent tech next time. That way you won&#39;t be posting to a NG and looking like a complete cheapass idiot.

Oh, and another thing, How much do you want for that new circuit board? LOL

[<kjpro]

It still runs, DUH! Why, you ask, because it&#39;s magical.

Were you the tech? I have to ask, since you&#39;re assuming the indoor blower isn&#39;t what he&#39;s talking about.

[Tony Hwang]

Hi, Me? I am no tech. Retired engineer from Honeywell after 30 odd years. OP said blower and compressor which made me to think ODU. Then wonder if he refered to compressor outside and blower inside?

[<kjpro]

More than likely the OP&#39;s talking about both pieces of equipment. Normal homeowner&#39;s refer to the ODU as a compressor. Not very many will call it a blower and compressor.

One never really knows, but the odds are in favor of the blower meaning the IDU. Which is likely the reason the Sears Tech (term used loosely) suggested the board replacement.

[Bubba]

I love your story, Raja. I wish I were the parts house for you. YOu must really be saving a fortune with all the home repairs you do. Bubba

[lytning]

Disconnect wire going to contactor on compresser. That should stop compresser. If not a stuck contactor could be the problem.

[<kjpro]

Do you read what you type? Or is it a fact that you don&#39;t know anything about HVAC?

[Stormin Mormon (on backup com]

By blower, do you mean the fan on top of the outoor unit, or the blower in the air handler?

Check for shorts, in the wire from the thermostat to the board. Check also for sticky contactor.

[Bubba]

Hold onto your wallets. Stormy is going to try another diagnosis. Bubba

[Mr.Tony to you]

Lytning You are right or check if low voltage is coming to line contactor if is not you line contactor is welded or frozen if power is present then is Tst how hard can that be to trouble shoot I would call Sears and refuse to pay for service call because apparently that was not tech. more likely janitor. Tony

[Zyp]

Unlike learning good speaking [typing] techniques.

[Zyp]

I knew there was a reason Honeywell&#39;s stock went up.

[Tekkie]

But they will have to take a charge against profits because they are looking for the crap Tony Hunglow worked on so the they can recall it. Lead paint - think stupid valve...