U-Line Freezer Error Code (L) (R) Temp Lo 12H+

This code means the left or right zone temperature has been running more than 10 degrees Fahrenheit below the set point for over 12 continuous hours. The letter in parentheses tells you which zone is affected. It is a sustained fault, so it will not trigger from a brief cold spike during normal operation. The first step is to check that the door is fully closed and the gasket is sealing properly.

A reset may temporarily clear the displayed error, but if the underlying condition causing the temperature deviation has not been corrected, the code will return after another 12-hour period of sustained low temperature. It is important to identify and fix the root cause rather than relying on resets alone. Persistent return of the code after a reset is a strong signal that professional service is needed.

If the fix is as simple as adjusting the door or replacing a worn gasket, costs are generally low, typically in the range of $20 to $80 for parts and minimal labor. If a thermistor or control board replacement is required, repair costs can range from $150 to $400 or more depending on parts and local labor rates. A service call for diagnosis is usually the first cost to factor in if the door and environment checks do not resolve the issue.

Start by verifying the affected zone door is completely closed and that the door gasket is free of damage or debris. Check whether the freezer is located in a space with unusually low ambient temperatures, which can push the compartment below set point. If these checks do not resolve the issue, contact U-Line Customer Care, as further diagnosis of the thermistor, control board, or refrigeration circuit will likely be needed.

This code indicates the compartment is running colder than the set point, not warmer, so frozen food is unlikely to be at immediate risk of thawing. However, excessively low temperatures sustained over time can affect food quality and texture. Monitor the actual compartment temperature and address the fault to keep the unit operating within its intended range.