Heat Pumps and Electric Heating - 7 Year Old Bryant Heat Pump - Dead?

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shoey
06-19-07, 02:48 PM
OK, I have a 7 year old Bryant heat pump that is not working. I did not use it much in the winter, and when Spring came, I tried to get it to cool, and nothing happened when I turned it on.

The circuit breakers were not tripped, although I reset them anyway. The thermostat seems to be fine. When I call up the cool function or the electric heat function, both the outside unit and thermostat make a single click. The inside fan turns on. When I turn the cooling/electric heat function off, I hear another click at the outdoor unit and indoor thermostat. I do not hear any other sounds coming from it when it is "on", even after sticking my head down next to it.

The outdoor unit itself looks very clean on the inside. I removed the fan and looked for anything visual that may be wrong and unplugged and cleaned the contacts on the wire that leads into the house.

I am assuming that I may have a problem with the capacitor and/or motor from reading a few other similar threads here. Is this the case?

How would you recommend proceeding, and where is the best place to get parts for these units?

Thanks in advance for any help on this. I am pretty good at fixing a lot of other things, but am just learning about these heat pumps.

Shoey


Ed Imeduc
06-19-07, 05:31 PM
When I call up the cool function or the electric heat function, both the outside unit and thermostat make a single click.
Is that the contactor in the outside unit that clicks????? Do you read 220V in the outside unit????

shoey
06-19-07, 06:29 PM
I believe that that it is the contactor that clicks. Is that what the plug from the house plugs into? It sounds like it is coming from there.

Thanks for the reply.

Shoe


shoey
06-19-07, 06:32 PM
Also, I do not have a meter here. I can get one from work if necessary.

Thanks again.

mattison
06-20-07, 06:33 AM
You need to verify line voltage out there and that the contactor is pulling in.

shoey
06-20-07, 01:04 PM
Thanks for the help, guys.

OK, I hooked up a meter to the contactor, and it read 240. I then found where the contactor gets pulled in, and it was not pulled in when I turned on the thermostat. I pushed it in, and the outside unit kicked on. There was a small spark when it went in. It is a single pole contactor. The unit had not been used in awhile.

The interesting thing is when I shut the unit off at the thermostat, I waited a short while for the unit outside to shut off and it did not. I had to trip the outside breaker to turn it off.

After I shut off the breaker, I eased the contacter out and turned the power back on with the thermostat in the off position. The outdoor unit still kicked on immediately. So, as long as the breaker is on, the outdoor unit now will not shut off.

Another note, I rechecked the voltage when I turned the power back on and the unit was running, and it read 120 whereas before it was 240.

So I gather that I will need a new contactor, and maybe some other parts. Where should I turn from here.

Thanks again, guys.

Shoey

shoey
06-21-07, 08:56 AM
I should have been more specific. Are there any other parts that I should replace while I am replacing the contactor?

Once again, thanks! You guys are a tremendous help.

Shoe

shoey
06-21-07, 06:24 PM
I went to the local Bryant dealer and got a new contactor that was the exact same as the one in the unit.

I replaced the contactor (it was definitely bad), and turned the breaker back on. The thermostat was turned off. The outdoor unit still fired up. The contactor did NOT pull in.

How could this happen? Could I have a short somewhere? First the unit was dead, now it will not shut off! Once again, the contactor is not in, and the thermostat is off.

HELP!

Thanks again,

Shoe

Ed Imeduc
06-22-07, 04:00 PM
Not sure what to say look for. The unit cant run if the contactor dont pull in. Check the wire hook up again . On the 220V

shoey
06-23-07, 05:54 PM
Thanks for the help, guys. I think it is some type of back feed problem. I posted it at another location and people are just as baffled. There is some good info here if interested. I also included some pictures.

http://www.askmehelpdesk.com/heating-air-conditioning/heat-pump-will-not-shut-off-103418.html

Thanks again for the help,

Shoe

ClassicDave
06-27-07, 10:52 PM
My best guess with out being there
Here is what I would do,
Take your Fan power wires off the contactor and capacitor.
Does your compressor Still run?
yes you have a short in your compressor windings, it is back feeding through your single pole contactor. If you went to a double pole contactor then you find the compressor would not run but it its getting it's power through that one leg.
somewhere in the compressor windings they are fused

Next take your compressor wires off,
Does your Condensing Fan still run?

If so then your short is there.

You definately have a short within the windings of one or both of the fan motor and compressor. This can cause motors to turn backwards or run off one leg of power. The Fan motor and or Compressor will get hot and go off on thermal overload. Check the amps the motors are drawing.

either way it looks like bad news.

you can also measure ohms from your compressor terminals.

(Run to Common) + (Common to Start) = Run to Start

Here is something I found that goes into a little detail about the Compressor Terminals. So I don't have to write a book I just copied and pasted and gave the link.


There are 3 terminals, C=Common, S=Start, and R=Run. The start winding between S & C and the Run Winding is between R & C. On most compressors there is an internal overload on the C terminal. If you get a continuity reading between S & R but show open between S & C and R & C then the internal overload is open. If the compressor is hot then wait for it to cool down and test again. The overload should be closed if the compressor is cool to the touch. If it does not close then replace the compressor.

If you have the compressor specifications, you can look up what the winding resistance should be. In most cases this information is not readily available, but there are some common guidelines you can use. The ohm reading on the run winding between R to C read be the lowest ohm reading, the start winding S to C will be the next higher, and the S to R which is both the run and the start reading will be the highest and should be equal to the sum of the other two.

I.E. Run winding C to R =2 ohms, S to C =6 ohms, and S to R = 8 ohms.

If the reading on S to R is less than the sum, then a short exist between the run and start windings. If one winding reads open or infinite then winding is damaged and the compressor needs to be replaced.

http://www.hvacoracle.com/cgi-bin/publish.cgi?p=306&s=cooling