Have recently done some work on an industrial refrigeration unit which is having an issue with liquid flood back. When the unit runs there is a constant build up of ice from the accumulator (whole thing) to the compressor. This then runs all the way up to the evap and freezes up.
The system has four evap coils each with a solenoid valve used for staging, water cooled condenser, recipricating compressor, is on R22 and runs a cooling tunnel at about 8 degrees C.
I believe this flood back issue has been a problem in the past as the suction accumulator appears to have been replaced recently.
On further inspection one of the txv's was faulty and replaced, however this did not solve the problem.
Unfortunatly I was only filling in at this site and will have little opportunity to work on it for some time but am very interested in helping solve the issue.