I just pulled out a bad start capacitor from an air conditioner unit. It is a 108-130MFD, 165Vac, 50-60Hz. Grainger doesn't have this one listed, and it appears to be obsolete. Does anyone know what different rated capacitor I could use in place of this? Also, why is it 165V if it's used on a 110V circuit?

 

its a 165v as 165v is its max capacity.... if it was 110v and a 110v capacitor it would be maxed out and probably overheat and explode! so you always rate it higher to stop this happening!

have you got the model number of the con unit? I'll try and help you find the right cap!

 

You can use any capacitor the same size, with equal or higher voltage rating. You'll probably wind up with a 370 volt capacitor because they are more commonly used on 230 volt air conditioners.