U-Line Refrigerator Error Code Evap T Open

The "Evap T Open" error code on a U-Line refrigerator indicates that the control board has detected an open circuit in the evaporator thermistor loop. The evaporator thermistor is a temperature-sensing resistor mounted near the evaporator coil, and it continuously reports coil temperature data to the main control board. When the circuit is open, no valid resistance signal reaches the board, so the system cannot monitor evaporator performance and triggers this fault code.

An open circuit in the thermistor system can originate at several points along the signal path. The most common failure points are the connector between the thermistor lead and the wiring harness, and the connector where that harness plugs into the main board. Moisture or corrosion at either of these connection points can interrupt continuity and produce the same open-circuit reading as a fully failed thermistor. Physical damage to the wiring, such as a pinched or broken lead, is another possibility.

Diagnosing this fault begins with inspecting both connectors for signs of moisture intrusion, corrosion, or loose pins. If the connectors are clean and fully seated and the fault persists, the thermistor itself has likely failed internally and needs to be replaced. Because an open thermistor prevents accurate temperature monitoring of the evaporator coil, the refrigerator may not cool correctly or may run continuous defrost or compressor cycles until the fault is resolved.