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View Full Version : Compressor or fan does not run intermittently


ncyankee101
Jun 11, 2012, 10:55 AM
I have a Goodman CPKE30-1b heat pump, about 14 yrs old, dual run capacitor.

A few weeks ago when we had our first hot spell in a while, I noticed the a/c was no longer blowing cold (it had been) so I went out and checked and the compressor was not running, though the fan was. I was going out of town for a few days so shut it off. When I returned it seemed to be running fine, cooled the house down 5 degrees in about an hour.

We then had a cool spell where the a/c did not run for a week or so. On the first hot day I turned the a/c back on, at first it was blowing cold air but a half hour or so later I noticed it was not. I checked outside and this time the compressor was running but not the fan. Turned the thermostat off for a few minutes, then back on - this time the compressor and fan both ran for a couple minutes, then the fan speed dropped for a couple more minutes, then stopped with the compressor still running.

There are some spider webs in the control unit that I am about to clean, but I don't see how they would cause problems like that. I am also about to perform some voltage checks on the cap and contactor, which results I will report back, but I thought I would post this now in case there is a common problem that could cause this type of erratic behavior.

ncyankee101
Jun 11, 2012, 12:17 PM
Ok an update - the system ran fine for a half hour after it was off for two days, the house temp has dropped 2 degrees in that time - I don't have an accurate thermometer to read the temp at the registers.

Next time I checked at around 40 minutes the compressor was still running but the fan was not. I turned off the system and am going to restart it in a few minutes to see what happens.

It seems the problem only appears after the system has been on for a while.

The compressor comes on when I push the contactor with the system set to off, is this normal?

OK I pulled the run cap and had it checked, the fan side was at 1.9 so I put in a new one - I assume this could have caused the problem I was experiencing, right?

mygirlsdad77
Jun 11, 2012, 04:06 PM
What was the rating on the cap? Definitely a good place to start.

ncyankee101
Jun 11, 2012, 11:23 PM
What was the rating on the cap? Definately a good place to start.

It was 34/5, and the compressor side reading was 40 which I guess could have accounted for the one time the compressor wouldn't run. That makes sense, right? - capacitance too high, hard start - too low, early shutoff.

Since then the problem has always been the fan shutting off early.

ncyankee101
Jun 19, 2012, 01:24 PM
Well it would appear replacing the cap has solved the problem, it finally got hot enough to run the a/c for a while and it has been going for over an hour without any problems.

mygirlsdad77
Jun 19, 2012, 03:21 PM
Good to hear. Thanks for the update.