AC buzzing, won't engage

Old 06-13-18, 12:00 PM
Thread Starter
Join Date: Jun 2018
Location: United States
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
AC buzzing, won't engage

So I already tried to troubleshoot what already appears to be a common issue in the when the unit buzzes and the fan motor won't spin, it is either a bad capacitor, bad motor, or both. I have already replaced both the motor and capacitor and am still getting the buzzing without the motor engaging. One video I watched, the gentleman said that the motor needs a minimum of 70+7 uf capacitor, however, the one that I pulled out of the unit was 40+5uf. I tried to look up specs/requirements of the new motor (which was the same as the one I replaced) and could not find anything that suggested how much uf it needed. So I guess this would be a two part question; is a 40+5 capacitor enough or should I return for a 70+7? And if that is enough, what is the next step in diagnosing why the fan motor wont spin?

Thank you in advance.
Old 06-13-18, 12:46 PM
Bob14525's Avatar
Join Date: Jun 2013
Location: USA
Posts: 1,744
Received 51 Likes on 44 Posts
You have a dual capacitor. The larger value of the two (40) is used by the compressor, while the smaller (5) is the fan capacitor. The fan capacitor should be the value specified for the particular motor. Bigger is not necessarily better.

It's unusual for a new motor and capacitor to not startup. The replacement motor should have come with something stating what the proper capacitor value is. Does the fan motor spin easily?

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: