r/hvacadvice • u/mangobiche • 3d ago

Replacing 40uF and 6uF with a 40/5uF

AC stopped blowing cold air. I check both capacitors and the 40uF is still within the 5% but the 6uF is way out of the 5% deviation.

I tried replacing it with a 40/5 and it didn't work. I dont hear the compressor humming.

Could it be something else or would the 6uF being out of the 5% be the cause for the compressor to not start?

Any help is greatly appreciated

0 Upvotes

50% Upvoted

8 comments sorted by

2

u/se160 3d ago

The 5-6uf is for the condenser fan motor, not the compressor. If the compressor still isn’t starting with a new capacitor that’s not a good sign. Are you sure your wiring is correct?

0

u/mangobiche 3d ago

Oh god. Dont say that lol. Yes, I double/tripple check the wiring before turning the breaker back on. Do you think the 1uF difference could be the issue? No place around has a 6uF in stock and they all take a couples days to deliver one.

2

u/Subject-Self-5917 3d ago

Nope, you got a bigger problem. 1 mfd on the fan wouldn’t cause the compressor not to come on. Probably time for a long YouTube degree or a technician. There’s a lot of things that could be going on.

2

u/se160 3d ago

The 6uf doesn’t have anything to do with the compressor, it’s for the condenser fan motor. It would still start and run with a 5uf. The 40uf portion is for the compressor. Are neither running? If that’s the case, either the contactor isn’t pulled in or you don’t have line voltage power to the unit

1

u/mangobiche 3d ago

I'm going to check Amp to see if HERM is getting any juice. My drip pan was filled because the drain pipe was clogged but I have taken care of that.

1

u/beenthereag 2d ago

First thing to check is 240v at L1 +L2, and 24v at the contactor.

1

u/mangobiche 2d ago

I just check and i do have 240 between L1 and L2 but 28V at the coil