HVAC condenser fan motor humming

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ms1pob
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HVAC condenser fan motor humming

Post by ms1pob » Sun May 06, 2012 1:20 pm

I am a homeowner who tries to DIY as much as possible. Today I noticed that my Carrier AC unit was not cooling and the blower was continuously running. After checking the evaporator coils and drip pan for water buildup, I checked the outside unit for frost buildup. Nothing found. I then turned the unit on and heard the humming of the fan motor for the outside condenser coils. The fan was not rotating and the motor felt hot. I shut it off to let it cool down, then turned it back on and assisted the motor to turn by pushing the blades with a long stick. The motor started to turn slowly, then picked up speed. Although it continued to turn, it did so at a slower speed, never building up to capacity.
So, my question is - could the issue be with the start capacitor or both the capacitor and the motor? I don't know if this unit has a start/run capacitor, or just a start capacitor. Should I bite the bullet and just call in an HVAC pro? I just looked on line and priced the replacement motor for about $175 US plus shipping. I don't know what a capacitor would cost, maybe $10 to 20 US. Any recommendations or suggestions?

heatseeker
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- HVAC condenser fan motor humming

Post by heatseeker » Mon May 07, 2012 8:20 am

run cap on fan motor. Installed 300 to 450 if just a normal motor not variable speed . Bite the bullet and save yourself the headache.

ms1pob
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- HVAC condenser fan motor humming

Post by ms1pob » Mon May 07, 2012 1:44 pm

Thanks! I did call an HVAC man. They are coming out today. Quoted ~$120.00 to replace cap. Hopefully the motor did not get damaged. Thanks, again.

heatseeker
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- HVAC condenser fan motor humming

Post by heatseeker » Mon May 07, 2012 1:53 pm

let us no what happens.

Freon
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- HVAC condenser fan motor humming

Post by Freon » Wed May 09, 2012 11:06 am

Make sure they use the same microfarad rated capacitor. The voltage can be higher than the old one but the capacitance has to be the same or you will burn out the motor.

melijack
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- HVAC condenser fan motor humming

Post by melijack » Fri May 25, 2012 7:39 am

Its seems a big problem and you should contact the technicians.

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