Why is my air conditioner making a humming noise?

May 31, 2019

If your air conditioner is humming, it could be a sign of an electrical or mechanical problem. Take steps now to investigate the trouble with your air conditioner.


Probable causes of your cooling system’s hum could include:

  • The condenser fan motor on the unit could be unable to spin but still have power reaching it, causing resistance that produces a pronounced, and often loud, humming sound.
  • There could be a mechanical or electrical malfunction with the contractor relay switch, which is responsible for turning on the outside unit when the indoor temperature rises to the level where cooling is desired. When the contractor fails, it can create a humming sound.
A humming sound is a signal that something inside your air conditioner is off and needs examination. Contact the experts to inspect your system and diagnose the problem.