Heat Pump Not Cooling

[ApplianceDoctor]

I have a customer called and said that their heat pump was not cooling. When I arrived I confirmed that there was a problem and unit was not cooling. I found everything was running even the compressor was running. I connected gauges to unit and found while compressor was running the high and low side pressures were equalized. This sounds to me like a bad or inefficient compressor. Is there any other thing or component could be bad in this unit that would cause the high and low pressure to be equalized while the compressor is running? Can anyone help me with this?

 

Thank You

 

ApplianceDoctor

[jumptrout]

What refrigerant is in system?

What are the pressures?
What are LRA draw? (locked rotor)

What is LRA rating?
What are running amp draw?

What is running amp rating?

Is reversing valve actuating or stuck mid range?

[ApplianceDoctor]

Refrigerant is R-22

Low side pressure 125 psig

High side pressure 125 or 130

LRA rating on compressor 48 amps

Unit is actually drawing while running 3.7 amps

Info. on label on unit is wore off could not see RLA

I can hear reversing valve clicking and energizing but

cant hear sound of gas switch.

Pressures are equalized or almost equalized.

[ahh-cool]

I don't work on a lot of a/c heat pumps, no heat in south florida, but it sounds like your reversing valve is stuck mid position. try hitting it with the back of a screwdriver and try putting on the heat see if it moves and what are the pressures in heat?

Ahh-Cool A/C

[jumptrout]

Running amps is too low.

Remove the compressor relay cover and check for a broken wire on compressor.

Verify the compressor capacitor is good.

[ahh-cool]

what size unit? 3.7 amps is probably ok with no load.

[ApplianceDoctor]

How would the compressor be running with a broken wire? Even if it had a bad capacitor, would the compressor still run as it is doing? I have run unit in heat and cool position and pressures are still equalized. Would a reversing valve stuck in mid position cause the pressures to be equalized?

 

Thanks

 

ApplianceDoctor

[ahh-cool]

again I don't work on a lot of heat pumps. the compressor pumps refrigerant to the reversing valve and the valve determins which way the refrigerant goes. if it's stuck in mid position it willpump to the valve and bypass right back to the compressor

[ApplianceDoctor]

Thanks guys for all your help.

 

ApplianceDoctor

[jb8103]

Sounds like he's given up on us.

 

I don't believe the compressor is running. He's hearing a lot of racket from the outside unit fan, and assuming the compressor is making some of that racket.

 

Where in the circuit did he check for amp draw? Did he mistakenly get the fan L1? 3.7 A would be about right.

 

It is not likely that pressures would be equal on both sides if the compressor was actually running. 125 PSIG corresponds to about 100 degrees F ambient, typical of an outdoor coil in the summer sun. The indoor coil P/T would correspond if he's taking pressures at the outdoor coil.

 

I'd have to be standing there to say for sure, but I bet our man has a bad capacitor.

Edited May 25, 2013 by jb8103

[ahh-cool]

the fan amp draw should be anywhere between .8 and 1.5. 3.7 is too much for a fan, unless the fan is bad