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Wrong run capacitor?

1157 Views 12 Replies 4 Participants Last post by  Bitters
My question is about my run capacitor for a heat pump unit. The compressor says it requires a "45 mfd 370v" capacitor, but the run capacitor on the unit is 25+5mfd. Is that the wrong capacitor for the unit or is there some other reason the run capacitor is less than what it says on the compressor?

Thank you!
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Yes, that's the wrong cap, should match the compressor.
Guess that would explain why sometimes it would work fine, and sometimes it wouldn't engage the compressor....
I'm surprised the 25 mfd would start the compressor.
Capacitors have a tolerance rating on them .Some are as much as 10% depending on the quality .You should try and match the capacitance as close as possible .The voltage is fine as long as it meets or exceeds the requirement.
Every time the ac/heat was off for a while it would be a pain getting it to run again. I'd have to flip breakers numerous times and 'something' would eventually catch and the compressor would work.. it would work fine for weeks/months till either it set for awhile without coming on, or the power would flicker/go off.. then back to flipping breakers. I've told 3 different service men this and they just wanted to add freon, which I did twice.. second time I had them put a sealer in. Guy that came yesterday (guy #3) said may be time for a new one since it's 15yrs old.. said the pressure was low, but hard to say since compressor didn't work.. he checked the capacitance and the capacitor was in limits for what it was labeled, but not that it was the correct capacitor.. so have a new run capacitor coming..
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After the right cap is installed and you are still having the same problem, ask them to install a hard start kit. Might gave you a few more years.
So you think just putting the right capacitor in won't fixit?
He is only saying "if" it isn't enough. Try the correct standard cap first, then if that doesn't cut it get a hard start cap kit. Old worn out equipment sometimes will need a little extra kick is all.

So you think just putting the right capacitor in won't fixit?
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Well the new run capacitor didn't do it.. I was watching the electric meter as the compressor was trying to kick in and it would occasionally speed up for a second or two, but never fully engage. Does this mean that either my compressor is shot, or I'm low on freon, or possibly both, other? I could drop more cash and get the hard start kit, but it still may not work. thoughts?

Left feedback to the HVAC repair company that was out three times and didn't notice the wrong capacitor. Supposedly they are going to call me Monday, see what they offer as a remedy.
Best way to see if the compressor is bad is to OMH it out, Does it trip the breaker?
Best way to see if the compressor is bad is to OMH it out, Does it trip the breaker?
Not familiar with how to do that.. did a quick google search and no luck. Have any links or can you explain the process?
Go to youtube and check out drzarkloff. He has some good vids.
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