The dual run cap on my central a/c condensing unit went bad (had a hole in the side of it, leaking). It was a 35/3 mfd 370v dual run. I ordered one on eBay http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT, and I have installed it. The contacter is working, and if I flip the outside breaker on, the unit will cut on (fan and compressor) and will run for 5 seconds and cut off. I shut off the breaker, waited 5 min, and did it again, same result.

I then looked more closely at the cap and saw that it is actually a 470v. I didn't think that would matter, but would that be my problem? Or just a bad cap? Or did something else happen at the same time that the cap exploded. A/C was working fine, one day it wasn't, found the fan and comp not running, but very hot, found the bad cap. Thanks in advance for your help.

Curious to hear opinions on this. I have used 470v in place of 370v in emergencies and never had a problem, or course I have always ordered the correct cap and changed it out, so I wouldn't know about long term. Anybody have some info on this. I don't think its going to hurt anything as long as your system is a 240v system. Now if the system where a 440v commercial system, you wouldn't want to use a 370 in place of a 470. Im thinking the 370 or 470 is just the max load you can put to the cap.

Maybe a bad Cap? Do you have a Capacitance Meter or a Analog Volt Meter?
Verify the Correct cappacitance is connected to the correct wires.

All seems to be working now. I'm guessing that being that the thermostat was calling for cooling, and I simply installed the cap and then flipped the breaker, that the cap had no charge stored, thus causing my problem? I simply left the thermostat in cooling and the breaker on. Went back out an hour later and she's running, don't know for how long.

Glad its working.