Found the Reach-In Cooler unit on and working. Allowed the unit to run for awhile. Noted that the compressor came right on when plugged in. Found the display went into a defrost and the compressor stayed on. Tapped the relay on the control board for the compressor and the compressor shut off. The compressor did come back on after the defrost cycle. Need one MDLSC Carel controller. Made some phone calls to try to pick up locally. Could not. Need one MDLSC Carel controller. Part identified by the manufacturer. 2/21/20 Removed defective temperature control, installed new temperature control, removed defective relay board, installed new relay board, turned on unit, allowed unit to cool, tested operations, confirmed unit working correctly at this time.