Heat/AC keeps tripping breaker

Hello,
Is "firedawgsatx" or John still around? He helped me the last time and was very helpful.

Anyway my heat pump won't turn on either heat or AC mode it keeps tripping the breaker. I put a new breaker in just to try it for a cheap fix but still the same. You can hear the compressor / unit try to start and then it cuts out right away tripping the breaker. So if someone can please help and maybe give this a shot trying to figure it out I would appreciate it if John is not around. I'd like to talk to him again but I guess it really doesn't matter. Let me know what all info and or pictures you need and I will post it.

Thanks,

Nick

 

Hi Nick, pics are a help but more importantly the model # mfg. info,any wiring Dia. Also

 

Most of the time when this happens the compressor winding is shorted to ground. Pretty easy to check just lock out the power and pull the leads off the compressor you should see three prongs once you get the cover and wires off. Most modern compressor plugs have the wiring built into the plug but if you have something pretty old you may need to tag your leads BEFORE you take them off to make sure you reconnect correctly. Use your multimeter to check continuity from each prong to a good ground on the cabinet. if it shows good there then check between each 2 prongs and report back with those readings there should be a lot of resistance between the prongs. If you can get down and see the marks there will be a C R and a S. Should see like 3 between 2 of them then maybe a 2 between the other two and then a 5 between the other two if the compressor is good. Do you see where the paint is burned off the top of the compressor or anything that might indicate an overheat condition had occurred?

 

As a precaution.... if you or anyone else reading this thread removes the wiring cover from the side of a compressor... wear safety glasses in case of a refrigerant breach.

I haven't seen either of those two in a while. I'm still here.
You could also have a defective start capacitor.

 

Yes every precaution should be taken. Safety glasses / full face shield / long sleeve shirt and gloves should be used just like if you were charging or boosting a battery on your car............ Might want to check the wiring from and including the connections at the contactor all the way through the circuit to make sure everything is tight. Make sure that you properly utilize Lock Out Tag Out procedures for all power sources as called out in the OSHA manual before starting the project. here is a link https://www.osha.gov/SLTC/controlhazardousenergy/ "Safety first"

 

Thanks guys for the info. I'll see what I can find tomorrow and get back here with the post.

Nick

 

I threw a start capacitor on it for another cheap fix, still the same. I noticed a valve on the reversing valve with a two prong connector I think is very hot to the touch. The second heat pump for downstairs is cold when I touched that one. That unit works fine. And with the power off the fan runs a slow speed on the unit that won't cut on??

 

Here is a pic of the part that's hot to the touch. It has the shiny metal bracket with a bolt through it in the black connector on top.Its actually a magnet that clicks when you unplug and plug it back in. Very hot to the touch also.

 

Does the plug or wire assembly just pull straight off the compressor? Its on there pretty tight i wasnt sure. Do o just pull it off or is there a trick to it?

 

It comes out a little like a cork. Just wiggle it out.

I put on safety glasses before checking this area because if the terminals are damaged they can shoot refrigerant oil out at over 200 psi.

 

200psi? Holy smokes now I see why the need for a full face shield as the one guy said. I've got face protection and I'll use it before doing this no doubt. Thanks for telling me I had no idea . I just hope I can figure this out so we don't have to pay a small fortune to get the local HVAC man out here. Still may have to regardless depending on what it needs. I'll see what happens tomorrow.

Is that magnet on the reversing valve suppose to be hot? It is cool on the other heat pump that does the downstairs . You can hear a click every 30-60 seconds or so coming from the compressor it sounds like but not sure. In the winter the heat pump kept kicking out with a code telling me low pressure cutout I think. I'd reset it and it kept woring until it kicked out again. It always acts up it seems.

 

It was trying to tell you that your system is low on refrigerant.

 

I can add refrigerant to my car but a home heat pump requires special equipment I'm guessing? I been a mechanic all my life and can fix about anything but if the system needs refrigerant I don't have any gauges. I probably need to called a repairman at this point don't you think? Doesn't sound like I'll be able to fix this myself. I was trying to avoid a huge bill hoping it was a simple fix. The last 3 or 4 issues I fixed but this may be a different situation.

 

Yes..... charging your home system requires the services of an EPA certified tech with the proper gauges.

 

Yep, well thanks guys but looks like a phone call is needed this time. I appreciate the v effort for trying but this one is out of my control. Thanks again.

 

Can you unplug the low pressure switch and jump it on this system to see if it will run? We did this on autos when low on freon to make sure the compressor would run first. Is it the same on a heatpump?

 

Yes, you can jumper the low pressure switch to see if the system starts. However, don't run it for any length of time, as you could cause damage to the compressor. I wouldn't suggest running it more than 15 seconds or so.

 

Ok thanks Bob... I jumped it and it cut right on, ran for 7-10 seconds then I shut it down. So now I'm thinking I need freon and a sniffer test.

 

Just keep in mind that we don't discuss charging issues, methods and pressures here as the EPA has mandated that a certified tech needs to handle those repairs.

http://www.doityourself.com/forum/ai...ng-your-c.html

 

I charged many autos back in the early eighties with R12. No special containment machine or anything. No certification just fix it. Anyway I'll get this taken care of now. Should be a simple fix and a reasonable bill. Thanks for all of your help guys.