Trane heat pump won't cool?

Question

I have a Trane 2TWB heat pump that won't cool. When the system is set to cool, the blower circulates air in the house but nothing turns on at the condenser unit. The circuit breaker keeps tripping 'off'. The outside disconnect doesn't contain fuses, the single pole contactor is pulled 'in' with 20 volts. The condenser and fan are not running, the fan isn't seized. The outside unit is pretty clean and I don't see any burned wiring. How do I test the motor capacitor to tell if it's the cause? Or could the system just be low on freon? Thanks

Answer 1

If I read your comments correctly, you stated that the breaker keeps tripping. Does it trip immediately? That would indicate a short to ground. The contactor coil gets its power from inside. Using what I think you are telling me, I would use an ohmmeter to look for a short to ground. This is done with the power off. Clean off a piece of copper tubing in the unit and check from there to the power side of the contactor. Then to the load side. If you get a reading you will need to check the compressor (with the terminal wiring off )and then the fan motor and so on. The idea is to trace it down to the source of the problem. Hope this helps you out. It is difficult to troubleshoot without being there to see for myself.

Answer 2

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RE:
Trane heat pump won't cool?
I have a Trane 2TWB heat pump that won't cool. When the system is set to cool, the blower circulates air in the house but nothing turns on at the condenser unit. The circuit breaker keeps tripping 'off'. The outside disconnect doesn't contain fuses, the single pole contactor is...

Answer 3

Are the coils in the air handler freezing up? If so you are definetly low on freon. If you kept resetting the c/b and continuously ran the a/c with low freon you may have burned up the compressor. You won't see any burned wires, because it would be all internal. It's like running a car without oil, the inside of the compressor gets so hot and soders itself together causing a short and tripping the breaker. You can perform a test with a multi-meter by testing for continuity on the +/- connections on the compressor itself. But you should have a trained professional come out and do a free estimate and he will tell you what is going on.

Answer 4

It could be as simple as a bad contact switch, or bad capacitor. Or as major as a blown compressor. It's probably something simple related to the power supply as you say nothing is coming on.
Best thing to do is call a professional to check it out for you, as you really have to be licensed to work on it because it contains refrigerant.
Do'nt play with it, you could make things worse & incur more costs for the repair.
Hope this helped, good luck!

Answer 5

I don't think it is low on freon. To test the capacitor since it could be causing the circuit breaker to blow it would be shorted. With a meter set to low ohm, say 0 to 200 or what ever your meter is in low if the capacitor is shorted the meter will point toward zero. Make sure the power is off and that you take a screw driver and discharge the capacitor, from the terminals to ground or the case of it. You also have the compressor out there, that would have a condensor too. There should be two condensors for the fan, one for run and one for start.

Answer 6

if the contactor is in it should run....does compressor and fan motor just hum and then breaker knocks....if yes then it is possible that capacitor is bad especially if it has both comp and fan motor connected to it.....if fan motor tries to run and compressor dont then it could that each has its own seperate run capacitor and the one for the compressor is bad....or...on some units trane has a start capacitor and relay to help compressor start ...these could be bad....i just repaired one today and start capacitor, start relay and run capacitor was bad and had to be changed...it was doing same thing as yours but because compressor couldnt start it would knock breaker before fan could start....it could still be possible that your compressor is down and needs to be replaced...the home owner can make any repairs except for doing anything that would cause the freon to be released into atomsphere

Answer 7

In the cooling mode the buzzing was the contactor. In heating mode, it could be the reversing valve, or it still could be the contactor. On a service call, I would test those components, the capacitor for the fan, the disconnect box fuse/switch, check loose wiring connections, terminals. edit: and the fan blade, motor.

Answer 8

probally low or the oriface is restrited time o call a pro as you will need a gauge set to properly diagnose this one