20 Most Recent True TSSU-48-12 Refrigerator Commercial Questions & Answers

Either low on refrigerant or a blocked capillary tube. Since you have attached a gauge I assume you have tried adding refrigerant so the next step is to replace the capillary tube and drier and weigh in the charge.

The symptoms are consistent with a bad thermostat. Start with being sure fans Inside and at the Compressor are running and if so replace the thermostat, if the unit still malfunctions, you'd need a refrigeration tech. That altitude won't make any difference. The Salad top units are just fine up to 7000 feet ASL no problem.

You will need to adjust the thermostat.
The thermostat will be hidden at the bottom back of the fridge near the compressor.
You may need a screw a flat blade driver driver to adjust the themostat

This hinge is a cartridge and the bottom hinge has to be removed to replace it, then you just unscrew the cartridge and change it out, it's pretty simple.

You will need to replace the defrost thermostat on the coils.

cooling coil freezing

Yes for sure it is the thermostat but whether the unit has failed or if the controller is faulty or a wirelink had cut off is to be found out with a detailed check.
Look from the controller and see the sensor, if intact and at lower settign of temperature the compressor does not cut off, the thermostat is faulty.

Question edited for clarity. The Service Manual says that the wiring diagram is hidden in various parts of the unit. https://www.manualslib.com/manual/1177583/True-Gdm-Series.html?page=43&term=wiring+diagram&selected=1#manual It doesn't appear to be all in one place, but you could contact their Customer Service, or Technical Service Department? https://www.google.com/search?q=true+gdm-35em+wiring+diagram ..