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Looking to replace a capacitor in a room air conditioner. The unit runs on 110 vac, but the suspect capacitor is labeled 250 vac 10uF unit. Is the 250 the rated output?
Thanks again for all the responses. Here's the back story. I recently retrieved a large window air conditioner that has been sitting idle for several years. When I put it in place and powered it up the blower fan came on directly. However when the compressor triggers to cycle it does not, it causes the blower fan all but stop. It seems as if the current supply is being drained. So I figured the start cap may be faulty. After checking on line there are 2 caps in the system. One for the compressor motor (large) and one for the blower motor (smaller) the larger of the two was still available from Admiral. The second which I knew I did not need is NLA so I was looking for alternatives when the original topic arose. Thanks again.
LT, so the fan did come on and run okay initially. Yes So is the fan running all the time and when the compressor try's to kick on, the fan motor stops or comes close to stopping? Correct That doesn't sound like the fan starting capacitor is bad. Agreed But it does point to maybe some corroded terminals. If the fan comes on without the compressor running, then the fan starting capacitor is doing its job.Again agreed, I was looking to see if a replacement was available(should it be required in the future) because the original part was NLA on several online parts websites. The fact that it nearly stops when the compressor kicks in points to something draining the available current and the fan suffers from that.Yes, and the compressor motor never actually starts, that's why I think the compressors start cap is bad. That part is still available online. So unplug the air conditioner and start checking connections. Could be some iffy wire nut connections or screw connections need cleaned and you don't need any starting capacitors at all. JMHO!
The 10 uF cap on the fan motor is a run capacitor as most smaller AC fan motors are PSC (Permanent Split Capacitor) motors. Sounds like a problem with the compressor. Could be a number of things such as frozen compressor, open start windings, bad start relay, etc. First thing I would do is check resistance of windings of the motor. If that checked out ok then grab a few of jumper wires and a good start cap and by connecting the right connectors on the compressor and holding a jumper against the start winding pin check the compressor to see if it would run at all. Not for the feint of heart but the quickest way to test rather than throw parts at it. What was the rating on compressor capacitor? Some of the smaller units do use PSC compressor motors and can be revived by the addition of a hard start kit.
When I put it in place and powered it up the blower fan came on directly. However when the compressor triggers to cycle it does not, it causes the blower fan all but stop. It seems as if the current supply is being drained.
GM, thanks for the response, see above in red.