Derek ColeGM, Simmons One Hour Heating & Air · AI HVAC Answers

Bad Capacitor Causing Unit Humming Noise? Call a Pro! #shorts

19 Mar 2026 · 0 min

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0:28

In this short video, Derek Cole explains that a failing capacitor prevents an electric motor from turning, which results in a humming noise as the motor attempts to draw power without success. He identifies the likely cause as a bad capacitor and advises viewers that the humming noise and non‑functioning unit indicate the need to call a professional for repair.

The capacitor is trying to turn that motor. So when the capacitor goes bad, that motor can't turn. So then you hear that kind of a humming noise of the motor trying to get power, but the capacitor is out. Therefore, you're not getting it to operate. So it's probably a bad capacitor, but the humming noise and the unit not working means you need to call a professional. The biggest reason you have a humming noise is a bad capacitor.