Please help!!

My outside unit not working both fan and compressor, and it keep tripping the outside circuit breaker within second after I tried to reset the breaker.

Here what I did so far:

1. Remove the dual capacitor, reset the breaker, it tripped again even without the cap in the circuit.

2. Check the cap per instruction in the internet (low resistance then OL) both fan and compressor side seems OK

3. Remove the contactor (24V relay) , one contact surface sticked, repair and clean and test to make sure the contactor working Ok .

4. Install both cap and relay, reset the breaker, no more circuit breaker tripping.

5. Even thermostat is in "off" position (inside the house), the moment I reset the breaker, the fan start running. However its speed seems slower then normal. The fan keeps running as long as the circuit breaker is on.

6. Change the thermostat from "off" to "cool" : the circuit breaker trip again, shut off power to the the outside unit

7. Change "cool" to "off" , reset the breaker, the fan running OK again as in step 5.

Question:

1. Why the fan running even the thermostat is in "off" position??

2. Why the fan speed slower then normal? Can it be a "closed to bad" capacitor??

3. Shall I get the new cap??

Thank you for you help

It sounds like you may have miswired something, can you post some pictures of the electrical panel?

I recorded every wiring before I removed the cap and the relay. The cap has three terminals, 2 yellow wires go into common tab, the brown wire goes into compressor tab and blue wire goes into fan tab.

The relay has 24V and ground go into the coil, two 220V wire black and white go into one side of the relay. Other side has 2 yellow wires (comm) and 2 black wires.

I am very sure (100%) that the wiring are correct.

Thank you very much for your input

I get this from an other forum:

"There are cases where a grounded compressor or bad fan motor will cause the fan motor to run slow even though the contactor is not pulled in. A bad run capacitor will cause the compressor not to run and the same for the fan motor..."

This is exactly happen to my unit, the fan running even thought the relay is not pulled in, and it running slow also.

What does "grounded compressor " mean?? How do we fix this

Question:

If the relay is not pull in, in other word, the thermostat not call in yet, then how we determine that the compressor is "grounded"??

A grounded compressor or fan motor is not something that can be repaired, you would need to replace either or. The "relay" you are talking about is a contactor, does it have contacts on both sides, or just one? Do you own a voltage meter?

It is a single poles relay. However it has 2 pairs of contact for 220V. One side of 220V is feed through. Other side is connect bywhenever the relay pulled in.

Yes I have aVolt meter. How do I verify that my compressor is grounded??

I hope that just the bad fan motor instead of a grounded compressor.

What do you think??

My guess is the motor, switch your meter to ohms, put one lead to the ground lug on the unit and the other to the load side of the contactor both sides, see what you get, if you get readings, disconnect the compressor wires, if you still get readings, the fan is grounded, if not, it's the compressor.

First, with the contactor open, and the power on, take a voltage reading on the load side, What do you get? Chances are, nothing is grounded or the breaker would trip, you may have a shorted fan motor.

Thank you very much. I decided to call the service guy this morning. I have 10 year warranty on the cmpressor and this is a 8 year old unit, so I still have 2 years left.

I think the compressor is shorted to ground, the voltage is bleeding from this shorted leg through the cap and causing the fan motor to run at haft speed 120V .

Yes, Indeed, the compressor is DEAD shorted to ground.

Does the warranty also pay for labor and material?? I have 2 years left on the outside unit.

What is the procedure the change the compressor?? How much will I have to pay??

It depends on what type of warranty you have, if you have 10 year parts and labor then you will not have to pay anything, this is something you will need to ask the technician. I'd say you are looking at about an hour and a half, of labor, it's usually a pretty simple task. Good luck!