The refrigeration unit will stay for days to over a week at the 36 degree set point, then randomly will go below freezing. I suspect the Thermostat and would like to know if anyone else has seen this same problem before I order it.
That cooler uses a Dixel digital cold control. So what is causing your problem, I suspect the thermistor connections are not secure to the controller or the thermal stresses of the evaporator is effecting the accuracy of the thermistor. What it comes down to is the controller is seeing a resistance that is higher than the evaporator’s real temperature.
One other item that may cause it, the thermistor bonding to the evaporator coil. The coil in a cooler has to get down to between 14 and 19 degrees before the compressor stops to get the box to temp . Called take down. Most evaporator take down’s are about 15 degrees F If the bonding clamp is loose, it will read box temp instead of coil temp.
Make sure to verify with a independent calibrated thermometer that the box temp is indeed freezing and not a reading error. Note to cooling light and fan lights if lit or not. I want to make sure you have a manual for the controller. to you can rad any codes and set the low temp alarm.
Thanks, the temperature on one occasion was 17 degrees and things were frozen solid, and some items had burst. Will set the low temp alarm next time I’m over there and see if I can get to the bottom of this extremely random problem. I believe the part number for the electronic thermostat has changed slightly, but don’t know if they were having problems with the original one or not.
Well, the problem that I found was that the Evaporator Fan Motor had gone bad. It would try to start about every 7 seconds but would not run. Replacing it solved the problem. It’s the simple things that we occasionally overlook that has a tendency to trip us up over time. Comes with age, I guess. Thanks all for your comments and help!