Air handler works intermittently


Old 10-17-04, 07:41 PM
The Mad Hermit
Visiting Guest
Posts: n/a
Unhappy Air handler works intermittently

I have a 5 year old Goodman A60-10REVB/C air handler unit. The thermostat and compressor seem to work correctly all the time, but the air handler doesn’t come on some times. When this happens, I notice the area around the air handler intake vent get a little chilly and the air handler fan does not come on (Seems like everything is working but the fan). To get the air handler fan to turn on I go to the air handler unit and turn the circuit breaker off. I wait until all the gurgling stops as the water leading to and from the unit stabilizes. When all is quiet (about 30 seconds after I turn the circuit breaker switch off) I flip the circuit breaker switch back to on. The air handler makes its usual sounds during power-up and then within 15 seconds the fan comes on and all is good again. Once working, the fan from the air handler has no problem staying on for the duration of the cooling cycle. It’s only after the temperature reaches its pre-programmed setting that the fan will turn off (as it should). When the temperature increases above that setting however, and the unit turns itself back on, the intermittent behavior of the air handler is displayed (i.e. it might come on, or it might not… Depending on its mood I assume). The fact that I can apply a work-around (by toggling the circuit breaker) suggests that the fan works. Note that the circuit breaker does not trip. It is on when I experience this problem, and I manually turn it off and back on to apply my work-around. So the question is, to those of you with a more intimate understanding of the inner workings and hidden mechanisms of air conditioning systems, is:

1) What is the most likely cause of this behavior? (Relay? Capacitor?)
2) How do I verify it?
3) How do I fix it?
4) Is there any good literature available with regard to this?

Any help would be greatly appreciated.
Sponsored Links
Old 10-17-04, 08:25 PM
Visiting Guest
Posts: n/a
What you have is a bad fan relay.

The fan relay used by Goodman is notorious for failing. I wouldn't recommend replacing it with the same part. Go with an instant on / off relay instead of the time delay that is in it. It will require a little know how to replace it with a different relay and if you could get a new one just like you got then it would be no problem to replace it, without much know how. Of course, I'm saying this with zero knowledge of your expertise, so don't take it wrong.

In the mean time, you could switch the fan switch at the thermostat to 'on' and leave it that way until it gets fixed. Your compressor will thank you and it won't cost much to run the fan full time.

Be careful, Randy Yates
Old 10-18-04, 07:09 AM
The Mad Hermit
Visiting Guest
Posts: n/a
Excellent! Thanks Randy

So assuming it is the fan relay, how do I go about replacing it? Will I have to desolder the existing relay or do these things fail so frequently that the relay is a plug-in piece. Also, once I remove the screws on the panel of the air handler is the circuit board with the relay typically easily accessible? And finally, how do I determine what type of relay I need and where can I get a new one? Radio Shack?

Thanks again for your help. You are the man!

-Mark A. Barros
Old 10-18-04, 03:24 PM
hvac4u's Avatar
Join Date: Aug 2001
Location: NW atlanta
Posts: 3,145
Received 0 Votes on 0 Posts
good answer heatpumpman, notorious is the word i use for that part going bad

it has a total of 5 wires (ithink) all spade connections, 5/16 screw holding it in place

it will take 2 minutes tops, do one wire at a time
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: