- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
Should you remove leads from capacitors before checking them with a meter? My condenser unit for my heat pump isn't running and I suspect bad capacitors.
Checking Capacitors
- Thread starter Little Bill
- Start date
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Yes, at least all but one.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
All leads from one terminal unless you know there is no possible circuit other than the capacitor being tested for your test current to flow through. For a single value capacitor anyway, dual value caps could have multiple circuit pathways and need more than just one terminal disconnected.
Bulge case in aluminum run capacitors is kind of automatic indication it is no good, they have a fuse link that pulls open when pressure builds up to cause them to bulge.
Bulge case in aluminum run capacitors is kind of automatic indication it is no good, they have a fuse link that pulls open when pressure builds up to cause them to bulge.
- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
Very strange!
I checked the capacitor, it was good.
I checked the contactor, including the coil. I even pulled it off to check the contacts and coil resistance, all good.
Put everything back and was going to check further. Now I had the disconnect pulled out, but the indoor unit was powered. As I was sitting there wondering what to to check next, I heard the contactor pull in. Had 24V on the coil and contactor working. Put the pull out back in and it fired right up!
Only thing I can think of was a loose connect somewhere, or coil or contactor stuck. So either taking the wires off and back on fixed it, or manually operating the contactor, got it going.
Whatever it was, I hope it stays and I don't have to have a tech come out.
I checked the capacitor, it was good.
I checked the contactor, including the coil. I even pulled it off to check the contacts and coil resistance, all good.
Put everything back and was going to check further. Now I had the disconnect pulled out, but the indoor unit was powered. As I was sitting there wondering what to to check next, I heard the contactor pull in. Had 24V on the coil and contactor working. Put the pull out back in and it fired right up!
Only thing I can think of was a loose connect somewhere, or coil or contactor stuck. So either taking the wires off and back on fixed it, or manually operating the contactor, got it going.
Whatever it was, I hope it stays and I don't have to have a tech come out.
Knuckle Dragger
Master Electrician Electrical Contractor 01752
- Location
- Marlborough, Massachusetts USA
- Occupation
- Electrical Contractor
Funny,
For what it's worth I had almost the exact same experience with my heat pump this weekend with the same end result.
For what it's worth I had almost the exact same experience with my heat pump this weekend with the same end result.
- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
Guess that makes us "Master HVAC Techs"!
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Stuck contactor (in open position) should likely have burned out coil when power was applied to the coil.
Sort of sounding like something happened in the control circuit and you weren't getting power to the coil.
ptonsparky
Tom
- Occupation
- EC - retired
More than one call where I fixed it and didn't know why for sure. I didn't like those, but at least I could charge.
I fixed a few without doing anything but show up.
I fixed a few without doing anything but show up.