so many capacitors

[CAPAZ]

I have a Whisperlite 3.5 KW genset, blew a capacitor and had one sent from the US rep at what seemed like a bit of a cost. Now am looking to buy a couple spars. It is a 35UF with only 2 spade type connectors. When I shop online there are SO MANY choices, AC, pulse , ceramic , Non GMO ( ok just kidding)

any advice?

[a64pilot]

Yes, go buy one at a HVAC supply house, I have found that GE Gentec caps way outlast the cheap Chinese ones, I mean the Chinese one may last a month and I’ve had a Gentec cap in there for about two years now.

Or go on Amazon and shop for 35uf GE Gentec capacitor. Now you will likely find 35+5 caps. That’s fine. What they are is combination caps for house AC systems, the 35 is for the compressor and the 5 is for the fan motor, just of course don’t use the 5 connector.

This is the one I have had very good luck with. You can get it for $8 as a 370V cap but the higher rated 440V caps are supposed to last longer and seem to.
https://www.amazon.com/Z97F9848-Volt...5686471&sr=8-9

[ttex]

Capacitors tend to blow when the temp gets hot. I change out a ton of capacitors on swimming pool pumps as soon as the temps get close to 100 F outside.

https://www.amazon.com/QH-QX6535-Cap...s%2C183&sr=8-3

This is what you are looking for.

Edit: OR what a64pilot said.

[a64pilot]

Originally Posted by ttex

Capacitors tend to blow when the temp gets hot. I change out a ton of capacitors on swimming pool pumps as soon as the temps get close to 100 F outside.

Yes, and I was real tempted to move my cap to the outside of the enclosure for this, but the GE cap has worked so well, and the factory mounting is right at where the air comes into the enclosure that I haven’t.

[Dsanduril]

What they said, go for the highest voltage rating you can get, just provides additional overhead.

If for some reason online is a problem, appliance repair places (washing machines, dryers, dishwashers, etc.) and pump sales/repair (swimming pool, small farm systems, water well, etc.) places will likely have a bucket full of suitable capacitors. In a pinch the exact rating is not critical, you could probably go from 30 uF to 40uF and still be in acceptable voltage range.

[ttex]

Yes, you can replace a capacitor with a capacitor of a higher rating. Never down. The problem is that the 40 is bigger than the 30 and it wont fit in the space reserved for the smaller one sometimes.

You can put a lower rated one in and it won't explode in your face or anything. It just won't work.

[Reefmagnet]

I wouldn't recommend changing to a different uF value when replacing a capacitor for a two phase motor. This value is designed to produce an optimal second phase angle. Using a different value changes this angle and decreases the efficiency of the motor. It's possible the motor will run a lot hotter which can lead to nuisance tripping or even burning the the motor stator windings out.

[CAPAZ]

thanks for all the advice. I know we blew the last one as we were running right at the top of the genset ouput in order to try and power a rather large AC fridge compressor. That is now off the boat replaced by a DC unit, way more sane.

All the same a few spares are always good. They don't have much selection here in Pohnpei, so USPS to the rescue!

ty all