I was hoping Moulder would get back to us on this. These True prep tables have a inherent problem with control. He stated that he set it at “0”, so he must have a mechanical thermostat. If it has been replaced with the wrong one or not bonded to the coil properly it will cause problems. They use a constant cut in temp to facilitate defrost every cycle. And it has to sense the evaporator core temp to do this. And the cut-out will be in the range of 10F to 12F. So that the air coming out will be about 15F to 17F at the bottom of the cycle. If the unit has draws, it becomes more pragmatic. Never saw a Draw unit that wasn’t. Especially if you have a active food inspector that likes to measure product temp.
Do I believe that his problem is control, YES. But replacing the control is not always the answer. Overloading can also factor in with this problem. I’d like to know if it freezes all the product or just near the evaporator discharge. And if all the evaporator fans are working correctly.