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UncleGnarley's avatar
UncleGnarley
Explorer
Aug 16, 2015

HELP! Run Capacitor size for Duo Therm 13.5k p/n57915.331

My a/c quit a few weeks ago. The model is Duo Therm Brisk Air 57915.331 - 13.5k BTU. I tested the unit at the beginning of the year and all was fine. I turned on the AC a few weeks ago while conne...
Golden_HVAC's avatar
Golden_HVAC
Explorer
Aug 16, 2015
The fan motor normally takes a 5 mfd capacitor. Even if you had a 3 or 4 or 7.5 MFD the 5 can replace it, and it will work.

The compressor can be anything from 35 to 50 Mfd. You what one of those to be 'close' to the right size, not off by more than about 5 mfd.

I have seen home capacitors in the 70 mfd range, but this one should be 35-50.

For a 120 volt compressor, a 370 volt rated capacitor is used.

Good luck,

Fred.

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