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Jessman
Jul 25, 2007, 11:57 PM
Hello everyone,

A few days ago, my AC went out; no heat, no air and no fan. I have a Goodman furnace and compressor. I checked the t-stat wires and there was no power. I replaced my t-stat (taking care to re-wire properly) and still nothing.

I traced the power across the entire system, starting with my breaker box, and I had power to the compressor and the furnace. I replaced the switch on the outside of my furnace (not necessary but it was suspect) and traced the power to the control panel in my furnace. I had power everywhere except the 24 Volts running out of the circuit board to my thermostat and back to the compressor. The fix ended up being the 3 Amp fuse on the circuit board. I replaced that fuse and pushed in the kill switch on the furnace, and the unit came alive and everything seemed to be fine.

I set the t-stat to cool (70 degrees) and left for about 2 and a half hours. When I came back, it was not cooling although air was blowing through the vents. It would run for a few minutes and then cut off - in cycles. I reset all the controls on the thermostat and made sure that the settings matched my system and still no cold air. I checked the compressor outside, and the fan on the condenser was not turning, so I turned off the system to avoid damaging the compressor.

When I was tracing the power across the system, I tested the compressor by pressing the points with a screwdriver. When I did that, the unit came on and everything functioned properly (including the condenser fan). So, now that I have power to the compressor, which responded properly when tested and currently makes noise when activated, and I have power to the furnace and to the t-stat, as well as air blowing in the house; why is the condenser fan not working now and cooling as before?

Is there a reset switch for the compressor, or have I missed something? I thought I had a clean fix with the fuse because I have power everywhere else. It seems as though everything should be back to normal!

Please help!

Thank you for your time and assistance,

Jessman

XenoSapien
Jul 26, 2007, 03:40 AM
Perhaps the contactor. "...pressing the points with a screwdriver" I'm unsure what you mean here, or was that when you manually pushed in the contactor?

XenoSapien

esquire1
Jul 26, 2007, 04:48 AM
Check the coil in the contactor.(the piece you pushed in with screwdriver) If it is bad, it will not pull in the contacts.

Jessman
Jul 26, 2007, 08:55 AM
Perhaps the contactor. "...pressing the points with a screwdriver" I'm unsure what you mean here, or was that when you manually pushed in the contactor?

XenoSapien

Thanks for the reply XenoSapien. Sorry about the miscommunication. By pressing the points, I meant that I manually checked the contactor and everything seemed to be working.

As of right now, when I set the temp to cool on the t-stat, the compressor comes on and seems to be working, but the fan does not turn.

esquire1
Jul 26, 2007, 09:09 AM
If you spin the fan with asick or screwdriver does the fan continue to spin? If so the capicator is bad. If not the motor could be bad. Does the motor tr to start? Does ir make any noise? Is it hot to touch?

Jessman
Jul 26, 2007, 11:50 AM
If you spin the fan with asick or screwdriver does the fan continue to spin? If so the capicator is bad. If not the motor could be bad. Does the motor tr to start? Does ir make any noise? Is it hot to touch?

Thanks esquire1, I will try that when I get home in a few hours.

What is confusing me is if I manually pressed the points on the contactor and the entire unit started (including the fan), it seems odd for the fan to not work at all now! There were no additional shorts or problems that occurred when I was tracing the power throughout the system.

I will have a better chance to look at the unit this afternoon when I get home, and I'll post my findings. Maybe I just overlooked something simple (fingers crossed)!

Thanks again

acetc
Jul 26, 2007, 12:22 PM
Some times when a fan motor is going bad (bearings) it will run for a while and then get hot and quit working, after it cools down it might start back up until it gets hot again. The answer is to replace the motor ( recommend changing capacitor for motor as well)

Jessman
Jul 26, 2007, 05:33 PM
Well, I looked at the unit and tested the contactor again.

When I engaged the contactor the unit activated, but the fan would not turn. I left it engaged and it started to give off a little heat. I disengaged the contactor, and when I tried again immediately, it would not start, but in another minute I was able to start it again - but still no fan.

I was able to turn the fan with a screwdriver and it turned freely.

Where does that leave me?

hvacservicetech_07
Jul 26, 2007, 10:06 PM
Start the unit, give the fan a spin (with a long object) if it stays running, you have a bad capacitor.

Jessman
Jul 27, 2007, 05:04 PM
Start the unit, give the fan a spin (with a long object) if it stays running, you have a bad capacitor.

Thanks for the reply hvacservicetech_07,

I switched on the unit and turned the fan with a screwdriver. The fan kept running for about 10 seconds and stopped. I tried a few more times, and I was able to turn it with the screwdriver, but it never turned on its own again. Then it began to heat up and I started to smell something burning.

Does that mean that the capacitor is OK, but the fan motor is bad; have I missed any components, or are there any other tests I can try?

Thanks for your help everybody!

esquire1
Jul 27, 2007, 05:20 PM
Replace the motor. At the same time,whenever replacing any motor replace the capacitor as well. The size of the cap is printed on the motor. If you have a duel cap the higher value is for compressor and the lower is for fan.

esquire1
Jul 27, 2007, 05:23 PM
Time to replace the motor. Change the capacitor at same time as well. If you have a dual cap the higher value is for compressor and the lower is for fan. The cap sixe for fan will be printed on new motor.

hvacservicetech_07
Jul 28, 2007, 11:42 PM
I agree, it sounds like you have a bad fan motor.

Jessman
Jul 31, 2007, 08:59 AM
Thanks for the replies everybody!

I found the Goodman repair parts specs for the CK30-1A and bought a replacement motor with corresponding capacitor. I am going to put the new motor in today... hopefully I will have air tonight! I will let everyone know what happens.

A couple of things:

Does anyone have any advice or suggestions about putting in the new motor?

Is there anyway to double check the rotation on the new motor to make sure is correct before I put it in?

Thanks again to all!

Jessman

esquire1
Jul 31, 2007, 09:15 AM
Wiring diagram should be on new motor. Fan rotation= lay fan on flat surface and observe which blade touches the surface. If it is the left side it'sCW. If right side CCW.

Jessman
Jul 31, 2007, 05:45 PM
Trying to replace the motor now.

The new motor has 3 wires and the old motor was four.

Old motor 4 wires:

BR & BR/W to capacitor

BL & WH to contactor.

New motor 3 wires:

PU
BR
BL

It looks like PU & BR to capacitor
PU from capcitor to contactor
BL to contactor

Does that sound right?

acetc
Jul 31, 2007, 05:58 PM
L-2 ( white wire)off the contactor will go the capacitor with the purple wire (same terminel) the brown will go to the other terminel of the capacitor, the black will go to the contactor(L-1) .The wiring diagram on the motor will show the connections on the capacitor (make sure it shows the purple wire on the capacitor and not the black wire in the wiring diagram).