AC capacitor question

barnacle bob

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10:36a, 3/11/23

AG

I'm trying to order a spare run capacitor. Having a hard time finding exact match.

The current unit has +/- 10% tolerance. How critical is that? 6% is as close as I can find.

BenTheGoodAg

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11:00a, 3/11/23

AG

+/- 6% tolerance is better. Go for it.

Needs to be said - Make sure you discharge before touching the old one if it's still in there. There are some good videos, but watch a couple of them.

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Cromagnum

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6:03p, 3/11/23

AG

Getting a bigger capacity one works great as long as it physically fits the space the old one did. More startup energy.

BrazosDog02

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9:07p, 3/11/23

AG

You can see if it's discharged the same way you check a 9V battery to see if it's good.

Just give it a lick.

(Ok, I'm kidding. Don't do this.)

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Animal Eight 84

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6:18a, 3/12/23

AG

April 1 is coming up.
Just slip that charged cap into a buddy's jacket pocket that's hanging up.
At the end of the day he will put on his jacket, feel the weight and reach his hand into the pocket…..,.

Always good for a laugh.

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Texker

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10:45a, 3/12/23

AG

Don't overlook American made capacitors.

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BenTheGoodAg

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In reply to Cromagnum • 11:50a, 3/12/23

AG

Cromagnum said:
Getting a bigger capacity one works great as long as it physically fits the space the old one did. More startup energy.

I would not do this... Buy the size the manufacturer recommends.

More start-up energy reduces winding life (and I think this is a run-capacitor, anyway). Don't reduce the life of the $500-1000 component to save money on the $10 capacitor.

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javajaws

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4:10p, 3/12/23

AG

And if you keep blowing capacitors every year your motor is probably going bad. Make sure it spins freely when not under power.

Aggietaco

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8:30a, 3/13/23

AG

Considering that unit is a replacement, you might check to see what size the fan comes with from the factory.

Cromagnum

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In reply to BenTheGoodAg • 1:03p, 3/13/23

AG

BenTheGoodAg said:
Cromagnum said:
Getting a bigger capacity one works great as long as it physically fits the space the old one did. More startup energy.
I would not do this... Buy the size the manufacturer recommends.

More start-up energy reduces winding life (and I think this is a run-capacitor, anyway). Don't reduce the life of the $500-1000 component to save money on the $10 capacitor.

My startup fans went out 2x a piece on my home AC units until our AC tech installed slightly bigger capacitors. Trouble free for at least 5 years ever since.

UmustBKidding

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In reply to Cromagnum • 4:18p, 3/13/23

What is your definition of bigger? Higher capacitance? Probably not, higher voltage rating, absolutely. Most are 370V 440vac. But some are lower. Also many like made in usa, but there is crap at least marked usa. The $7 one may have had its quality leak out before you opened the box.