U-Line Freezer Error Code (L) (R) Evap T Open

This error means the control board has detected an open circuit on either the left or right evaporator thermistor. The thermistor is a temperature sensor that monitors the evaporator coil, and an open circuit means the board is receiving no signal from it. This can be caused by a failed sensor, a loose connector, or a break in the wiring harness. The freezer may not regulate temperature correctly while this fault is active.

Continuing to use the freezer with an open evaporator thermistor error is not recommended for food safety. The control board relies on this sensor to regulate the cooling cycle, and without accurate temperature data, the freezer may not maintain proper temperatures. Check the actual compartment temperature with a standalone thermometer and consider moving frozen food if cooling performance is compromised.

A power reset may temporarily clear the error display, but the code will return if the underlying fault in the thermistor circuit has not been corrected. The control board detects the open circuit condition each time it polls the sensor, so the error will reappear during normal operation. Resetting should only be done as part of a diagnostic process, not as a standalone fix.

A knowledgeable DIYer can start by inspecting and reseating the thermistor connector, which sometimes resolves the error without parts. If the connector is secure, testing the thermistor with a multimeter is the next step to determine whether the sensor needs replacement. Wiring repairs and control board replacement are generally better handled by a qualified technician.

If only the thermistor sensor needs replacement, parts typically range from around $15 to $50 depending on the specific model, plus labor if a technician is involved. If the control board is at fault, board replacement can cost significantly more, generally in the range of $150 to $400 or higher for parts alone. A diagnostic visit from an appliance technician usually adds $75 to $150 to the total cost.