Quote Originally Posted by abrando1 View Post
I am running Copeland 6TM1 compressors with R408A in Low temperature application. There are two compressors with similar TEV settings but one is running a discharge temp of 90 deg C (good) and the other is running a discharge temperature of 28 deg C (bad). What is going on? The cool running compressor is icing all over the compressor. The condensors of both are 200 psig. Suction of the cold compressor is 0 psig. The warm compressor is ~ 20 in hg vacuum (ideal for this application). How do you under heat a compressor?
Welcome abrando.
I'm with the Viking on this one!
Using the back to basics theory.
The most logical reason is because your compressor has liquid flood-back.
What has or is causing it you need to establish.
Hence the question from viking about the superheat readings.
The subcooling readings are relevant also.
many things can cause this, so check things like,, (in no particular order).
SUPERHEAT AND SUBCOOLING, CORRECT OPERATION OF THE EVAP FAN/S AND IS THE COIL/S CLEAR.
CRANKCASE HEATER.(NOT WORKING- IS COMP COLD UPON STARTUP)
LIQUID LINE SOLENOID VALVE (PASSING).
These are some of the more obvious contributing factors.
But with the little info so far it is hard to pin down what is actually happening.
So most of this is based on educated guesswork!
I hope it helps?
Cheers Grizzly