[gdwrnch29]

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.

[mygirlsdad77]

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.

[Stratmando]

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.

[gdwrnch29]

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.

[mygirlsdad77]

Glad its working.