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Heating, Air Conditioning, Fridge, HVAC/Air handler motor is noisy after replacing run capacitor


Hi Marcus,
My air handler motor stopped working at home. I called a tech who suspected that run capacitor got bad and so he replaced it. For first 6 hours, it seemed to run fine although with some noise however later the noise level increased and I noticed that at times, motor was not running as if not enough torque. I then called York to get specs of capacitor originally on the unit (my tech took away the old part with him) and was told that it was 7.5 microfarad. What I have now is 6 microfarad one which also has a 100K resistor mounted in parallel (which was not there on my old one as I recall).

Does the problem I have is because of motor itself or lower microfarad rating capacitor and/or 100K resistor mounted in parallel with the capacitor?

i will greatly appreciate a response.

     The wrong size run capacitor is a problem ( needs to be within 10% of required rating ). It will cause the motor to run inefficient , draw higher than rated amperage often the motor will cycle off on internal overload shut down . I don't believe I have ever seen a bleed resistor on a run capacitor before - don't believe it is needed . Start capacitors with much higher mf rating have the to bleed voltage off and save contacts on start device .
Hope this helps .   Marcus

Heating, Air Conditioning, Fridge, HVAC

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Marcus Cass


I can answer question regarding small refrigeration units ,walk in cooler/freezer,commercial ice machines,exhaust hoods,supermarket rack systems,all residential air conditioning units and commercial air conditioning equipment. No appliance questions please


20 years plus experience in supermarket chains , restaurant refrigeration service , and residential and commercial air conditioning service. Florida class A air conditioning contractor. Currently own an air condition and refrigeration company.

Graduated trade school , hundreds of hours of manufacturer training as well as in house training over the years and best of all - hands on real world experience . Class A license holder in Florida

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