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gotoman for ac
gotoman for ac, HVAC Technician
Category: HVAC
Satisfied Customers: 5206
Experience:  51 years of experience install design and repair of all makes and models of AC
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How do I test a capacitor on a heat pump

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How do I test a capacitor on a heat pump
The only way to test with ohmeter is take wire off capacitor and go from C or common to F and Herm. You will have to reverse wire. If the capacitor is good the needle will jump. But you will have to keep reversing leads to charge cap. This is the way we checked them in the old days. If your capacitor is swollen ot puffy on top that is also a signe of bad cap. Russ. I am here if you have anymore questions.
Customer: replied 7 years ago.

what does reverse wire mean?


Touch one lead to C terminal and one lead to either F or Herm terminal. If capacitor is good you will see alittle voltage spike on meter. Reverse the lead by just changing positions on terminals this will recharge cap. and it will spike a little voltage. When it spikes a little it will bleed back down to 0 volts. Russ
Customer: replied 7 years ago.

I took the capacitor out of the unit. It looks like the top is puffed around the C and FAN terminals. I think you said that is bad.Frown

I am using a didgital multimeter. I am getting infinite resistance w/o so much as a blip. That's not good, right?


Yes you have a bad capacitor. Need to replace it. Look on side of cap. You will see something like 35 uf 5uf 370 VAC. That is size of capacitor. You have gone this far you can change this yourself and save 150.00. Just call a local HVAC shop they will sell you one. Russ
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