Outside A/C fan not spinning - Need to verify it's the capacitor


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Old 04-15-13, 07:21 AM
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Outside A/C fan not spinning - Need to verify it's the capacitor

So I noticed the A/C was blowing warm air, went outside and discovered that the fan would not turn on. After spending a few minutes reading the forums, I performed the "stick" test and was able to get the fan going. I also checked the temperature of the copper lines by touch, and one was indeed warm and the other cool. However, a couple minutes went by and the fan turned itself off.

With the fan shutting down, is the capacitor still the likely culprit?

Thanks in advance.
 
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Old 04-15-13, 09:06 AM
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Welcome to the forums.

If you pushed the fan and it started turning..... that would suggest the capacitor.
If the fan didn't get up to full speed, it could thermally shut down which would still suggest the capacitor.

I would replace it first.
 
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Old 04-15-13, 09:28 AM
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Thanks for the reply, PJmax. Now to spend time removing the awkwardly placed capacitor

Thanks again.
 
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Old 04-15-13, 09:42 AM
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Be sure to turn the power off to the unit first.

After turning off power.....short capacitor to ground to remove any residual charge.
 
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Old 04-16-13, 11:05 AM
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Wasn't able to remove the capacitor yesterday due to being called away, but today is the day Anyone know a place in North DFW where I could find a replacement?
 
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Old 04-17-13, 07:38 AM
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I wasn't able to get to the parts store in time yesterday, so I had someone pick it up today. But there may be a problem.

Nothing is labeled and there is one thing missing...



It is a Dayton 2MDZ3. The one being replaced is a GE unit. Not sure which is the model number but these two are on the side 45F1181FB and HC96xxx25D (can't make out the middle three due to being scratched)

Should I go back and ask for another or will this do?
 
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Old 04-17-13, 10:39 AM
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I replaced the capacitor, but unfortunately that didn't fix the issue. There are also some things I forgot to mention, there is a buzzing sound coming from the unit. After examining the contactor I noticed burnt posts, but it was still able to pull in. What else can I do to troubleshoot?

Any assistance would be appreciated.
 
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Old 04-17-13, 11:57 AM
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Definitely replace the contactor. You may be getting a voltage drop across the terminals which is just going to cause more issues.
 
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Old 04-17-13, 02:40 PM
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use a volt meter and verify power across the contactor. Also, the capacitor in your post looks like a compressor capacitor and not a fan capacitor.
 
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Old 04-17-13, 06:19 PM
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That and a much smaller capacitor look to be the only two visible. It's a bit hard to read, but I'll try to get the model number of the AC unit tomorrow.



This is what I see in a box with a sliding cover with the contactor just south of these two. It's a bit dark out, so I'll have to wait for the morning to test.

Thanks
 
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Old 04-17-13, 06:28 PM
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The much smaller cap would be the fan cap. The larger one is the compressor cap.
 
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Old 04-17-13, 06:33 PM
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Of course it would be. For whatever reason I just assumed the larger one would be powering the fan.

I'll report back tomorrow.

Thanks!
 
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Old 04-23-13, 06:26 AM
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I was finally able to get back to it today (good thing for the 60 degree weather the past few days), and the fan is still not powering on by itself. How would I go about testing for power at the contactor?

Also, with the fan capacitor not having any labels (OEM and replacment), could it still be possible to install the capacitor incorrectly?

Thanks
 
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Old 04-23-13, 08:23 AM
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A two lead capacitor can be connected in either direction....there is no polarity.

You would use a voltmeter to check the wiring on both sides of the contactor. Supply in from house and switched out to compressor and fan. Both should be 240 VAC.
Is the compressor running ?
 
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Old 04-23-13, 09:27 AM
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Unfortunately a light shower started, may have to wait until tomorrow to check with the voltmeter. As for the compressor, the only tests I did a couple of days ago was check the lines. One was hot and the other cold.
 
 

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