One hot and one cold compressor

[Electrocool]

Hi!
I´m trying to troubleshoot a ground heat pump system. There are two compressors in parallel and one of the compressors is very hot and the other is cold. The cold one is frosty on the suction pipe. The system has only one expansion valve and one recipient.
Could it be so that the hot one is broken in some way.
Has anybody any ideas?

[bill1983]

how hot is "very"? is it hot on the body or pipework? is it hot at the top or the bottom? is the cold compressor running? is the hot compressor running?
more information will help.

[Electrocool]

Hi
Both compressors are running and the hot one is very hot on the body but the pipes seems to be at normal temperatures. The top is hottest.The cold one is cold and frosty on the suction pipe and the body is very cold and a little frosty where the suction pipe is connected to the compressor.
Thank you for your quick answer!

[Grizzly]

Hi Electrocool.
You don't give much detail about the system.
So I will give it a guess as to what is happening.
It is possible that the cold compressor has a Crankcase heater problem.
Which has caused any refrigerant vapour that has condensed during the off cycle.
To remain in the sump which with the temperature drop it causes would create the situation where further refrigerant could migrate.
Basically when turned off does the crankcase heater on both systems work?
Because it sounds as if your cold comp has liquid refrigerant within it.
On a smaller critical charge system the remaining operational system would run hot.
The above is just a guess at this stage, but somewhere to start would be the heaters as I suggest.
Also have a look at the common oil return line if there is one.
Paying particular attention to any solenoid valve control?
Good Luck I hope this is of some help?
Grizzly

[Electrocool]

Hi
Thanks for your answer. I´ll check it up tomorrow and then come back with more detailed questions or answers:)

[Grizzly]

Hi electrocol.
What is a Kylmontor?
Grizzly

[coolhibby1875]

possible that the head gasket is passing across some discharge presure into the suction side!

[Electrocool]

Sorry I´ve got wrong information. There is four compressors in a rack Two and two is in parallel and one of them is very hot and noisy but the pressures are ok. I think the problem with it is bad bearings. There was also a frosty compressor and suction pipe but is was a compressor in the other pair. I think that the discharge pressure is passing into the suction side exactly what coolhibby says.

[Electrocool]

Kylmontör is a swedish word and means refrigeration engineer