Air Conditioning - Capacitor Interchange

The start/run capacitor in my A/C unit is bad and the local (only) supply house is out of the exact one that was in my unit. It is a 5-30uF, 370VAC, +/- 6%. I know that a higher voltage can be swapped in but what about uF. Can any other uF combination be used such as 5-25 or 5-35? There is a secondary booster capacitor that looks like it was added a few years back but it is only for the compressor, and thus, the compressor will run but not the condensor fan.

Thanks for any guidance.

You should replace the capacitor(s) with the same rating.
Too high and it could cause the windings to overheat from too much amperage and too low and the motor might not have enough power to start.

If you have enough room you could use two separate capacitors of the correct rating.
Even though the compressor side still works it would be a good idea to change it anyway, especially since there is a booster capacitor on it already.

I suspect the booster is the only thing that is working. The original cap is all bulged out so I doubt it is doing much of anything for the fan or the compressor. The supply house has 5-25 and 5-35 so they will match up with the fan but not match up correctly with the compressor.

that cap is available at Johnstone supply their part number G33-077

Do you have a Johnstone Supply near you?

or at Grainger. Their part number 2GU33.

Is there a Grainger near you?

or at MSC. Thier part number;08687436

Go someplace else. That capacitor should not be hard to find. Alternatively, you can buy two single capacitors if a dual is not available. You can post back if you need help wiring two separate units.

If I did two caps then would I just connect the power from the contactor to one or the other then jump over the the other one. Then connect the fan to the fan cap and the compressor cap with the booster as it was before.

I don't have any of the other supply houses suggested, wish I did. Only the one local. The next closest will take me a half my work day to go and get back. Maybe I could send the better half.

The wiring scheme you described is correct.

The supply house had a 5 and a 30 so I put two single caps in. She is up and running again. Thanks for the help.