U-Line Ice Maker Error Code E1

The E1 code on a U-Line ice maker indicates that the Refrigerator Zone thermistor circuit is open, meaning the control board cannot receive a valid temperature reading from that sensor. This is typically caused by a failed thermistor, a disconnected wiring connector, or a break in the wiring harness. The unit cannot regulate the refrigerator zone temperature without this signal, so it halts normal operation until the fault is corrected.

A simple reset will not permanently clear the E1 error if the underlying fault still exists. The code will return as soon as the control board attempts to read the thermistor again. The error will only clear and stay clear after the open circuit condition in the thermistor or its wiring has been diagnosed and repaired.

If the fix is simply reseating a loose connector, there is no parts cost involved. If the thermistor itself needs replacement, parts typically range from around $20 to $60 depending on the specific model. If a professional technician is needed for diagnosis and repair, expect total costs in the range of $100 to $250 including labor, though this can vary based on your location and service provider.

Start by checking the thermistor wiring connector and reseating it firmly at both the sensor and control board ends. Next, OHM test the thermistor by submerging it in a 32 degree Fahrenheit ice water bath. A properly functioning thermistor should read approximately 16.1k ohms. If the reading is open or far outside that range, replace the thermistor. If the sensor tests correctly, trace the wiring harness for any damage or corrosion.

It is not advisable to continue using the unit with an active E1 error. Without a functioning refrigerator zone thermistor, the unit cannot accurately monitor or regulate temperature in that compartment. This can result in improper ice production, inconsistent food safety temperatures if the zone is used for storage, and potential long-term stress on the compressor from unregulated cycling.