Condenser fan of AC in packaged unit stops running mid operation


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Old 06-19-22, 09:32 PM
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Condenser fan of AC in packaged unit stops running mid operation

Turning on central AC first time this year today during excessive heat but the cooling didn't last long. AC worked fine for a few minutes until I hear and feel abnormally high vibration from the outside unit so I went out to see. The condenser fan had stopped running and the fins and the housing are pretty damn hot. The outside unit would then stop running (and vibrating) on its own or I went inside to shut cooling off from thermostat on the wall. Tried a few more times same issue. Works fine for a few minutes then condenser fan stops and unit vibrates high..

My unit is an older Lennox package unit that had its heat exchanger replaced in May. I had a feeling the guy worked on it was a fly by night type as he visibly faltered a bit when reattaching cables to the control board. The heating part acted strangely during test later but eventually seemed to run fine to make sure the new heat exchanger worked and not leaking CO.

Back to the AC unit. Could it be a bad job of reattaching wires to the board or wrong wire attached, or the capacitor? Suggestions appreciated.


 
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Old 06-19-22, 10:28 PM
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Could be a wiring issue but doubtful as the control board doesn't really control the A/C.
The condenser fan gets its power from the A/C contactor.
Could be a defective/weak capacitor.
As it's an old unit it could be a defective fan motor.

If you are trying to fix it yourself.... replace the capacitor first.
 
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Old 07-04-22, 04:50 PM
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Thanks Pete, it's been a while and I just got to open up the unit to check out the capacitor.

Turns out the 2 prong base on the capacitor has nothing attached to it and there is a light brown colored cable lay unattached. The 4 prong has one red and one purple cable attached in a perpendicular adjacency, and the 3 prong has one yellow cable attached to the middle prong.

Might it work if I attach the light brown cable to one of the prongs of the 2 prong base? That seems that it is for fan, and 3 prong for herm and 4 prong for common from the internet. Also, is attachment of cables to each group of prongs location specific? Eg. the red and purple cable on common, do they have to be attached perpendicular to one another or can they be attached parallel?

Thanks again.
 
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Old 07-05-22, 11:27 AM
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Pictures of what you are seeing would be very helpful..... How to insert pictures.
 
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Old 07-05-22, 08:37 PM
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pictures



 
 

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