# 404a operating conditions



## mikey14 (Aug 26, 2014)

Need help trouble shooting a small cospolich reach in refrigerator ,35 degrees, on my ship. This refrigerator has a small cold well on top as well that is run from the same condensing units as the refrigerator. So this unit has two evaporators both having their own liquid line solenoid valve and TXV. The refrigerated box has an EPR valve and the compressor is operated by suction pressures. This pressure switch has a cut in and cut out. I believe the cut in should be at 68 and cut out at 35. Correct me if I'm wrong with those numbers. I forgot to make a note of what the pressure switch was set at. It also has a sight gauge on the liquid line with some bubbly action in the beginning of compressor on but does clear up for the most part.

Noticeable problems
1. Evap frozen over
2. very low suction pressure
3. box temperature high

suction pressure was somewhere around 10 to 5 pounds
never even bothered to hook up high side gauge

looks like its undercharged but I have a sight glass with what I believe is mostly liquid. 

Any help is appreciated! Thanks all


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## cgfmechanical (Nov 12, 2014)

Try adjusting EPR valve. If that doesn't help, top off system to full sight glass. Don't exceed 215 head pressure


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## cgfmechanical (Nov 12, 2014)

Try adjusting EPR valve. If that doesn't help, top off system to full sight glass. Don't exceed 215 head pressure.


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## airtrackinc (Feb 12, 2014)

Evaporator pressure regulating valves respond only to the difference in pressure at the inlet. Inlet pressure acts against the bottom of the plug connector into the saddle disk), opposing force generated by die adjustable setpoint spring


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