The fan of my AC is working, but I hear a buzzing noise when the compressor should turn on, and then it doesn't. Is this a capacitor problem?

Answer

It could be, but I can't be 100% sure without testing it. That said, the hum is most likely the contactor being pulled in and asking the unit to turn on. It could also be that the motor or compressor is locked up and trying to run.

Updated on April 10, 2018

Original Article:

How to Diagnose and Repair Your Air Conditioner (A/C) Capacitor
By Dan Robbins
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