No cold air - HVAC issue

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Old 06-29-14, 01:41 PM
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No cold air - HVAC issue

Another issue as per many on this forum.

Our upstairs unit has stopped cooling. I replaced the dual capacitor last spring.

This time, the outside fan is running and the inside blower fan is running, but no cold air. (last time, the compressor fan did not run). Could this again be the replacement dual capacitor but it has failed only on the compressor motor (is that possible)? Best method to check this? Is the compressor enclosed next to the fan in the outside unit?

thx
 
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Old 06-29-14, 01:54 PM
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The compressor is directly under the fan in most condensor units.
I have a capacitor meter for checking capacitors but for the price of the cap it's easier for you to just replace the cap.
 
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Old 06-30-14, 08:40 AM
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is it possible for the compressor portion of the cap to go bad and the fan still be OK?

My multi-meter does not measure capacitance. Since I have two units, I may swap caps to see if it fixes the issue. My concern is doing so will somehow damage the good cap.

thx
 
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Old 06-30-14, 08:53 AM
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You shouldn't hurt the cap by swapping it.
 
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Old 06-30-14, 09:57 AM
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It is not uncommon for half of a dual cap to fail. A new dual cap should be installed when this occurs.

Uni T offers a $25 pen type meter that I use several times a day that measures up to 300 uF caps, voltage and ohms.

I bought it as a supplement to a Fluke 902 that has a poor ohm meter .
 
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Old 06-30-14, 10:38 AM
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I swapped caps and it solved the issue. Found a local supply shop that has a replacement.
Not happy this failed in 2 years (evidence of a bigger issue?) but pleased that was the only problem.
 
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Old 06-30-14, 12:20 PM
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Probably not a bigger issue, cheap caps (China?) fail pretty quickly. I had a fan cap that was indeed from China last me exactly 1 cooling season.
 
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Old 07-01-14, 05:36 AM
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I guess I'm having the same issue...my outside unit runs..my inside unit runs..but I'm not getting cold air..the outside unit occasionally makes a 1-2 sec hum..would this be a capacitor?
 
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Old 07-01-14, 05:40 AM
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It is usually the cap or the wire between the cap and the compressor start terminal is melted at one end.
 
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Old 07-01-14, 05:42 AM
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Sorry..Houston was that for me?
 
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Old 07-01-14, 05:44 AM
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If you had started your own thread it would be easier to tell that yes, it was for you.
 
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Old 07-01-14, 05:46 AM
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Whoops..thank you..I will work on taking it apart and take a peek.
 
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