U-Line Freezer (L) (R) Evap T Open: Evaporator Sensor Circuit Open
(L) (R) Evap T Open means the control on a U-Line freezer found an open circuit in the left or right evaporator thermistor, so it cannot read that coil temperature reliably.
What does U-Line freezer code (L) (R) Evap T Open mean?
(L) (R) Evap T Open is a sensor circuit message on a U-Line freezer. The evaporator is the cold coil that removes heat from the zone, and a thermistor on it reports the coil temperature to the control. The L or R on the display tells you which side. An open circuit means the control receives no usable signal, as if a wire were disconnected or broken. The freezer may keep running, but the control is missing information it uses to manage that side, so the cause should be located.
(L) (R) Evap T Open at a glance
- Code
- (L) (R) Evap T Open
- Appliance
- U-Line freezer
- Applies to
- U-Line freezer with left and right evaporator thermistors
- Type
- Needs attention soon
- Can you clear it yourself?
- Sometimes, after the safe checks below
- Most likely cause
- A connector at the evaporator thermistor that has loosened or been damaged
What you may notice with (L) (R) Evap T Open
- (L) (R) Evap T Open is on the display
- The message names one side of the freezer
- Cooling cycles may look different from before
- Frost may build on that side if it persists
How the freezer detects (L) (R) Evap T Open
Inside the freezer, the evaporator is the coil where refrigerant absorbs heat. A thermistor attached to it changes resistance with coil temperature. The main control feeds it a small voltage and reads the return to work out how cold the coil is on the left or right side.
That coil reading helps the control decide how long to run the cooling system and when frost on the coil needs to be dealt with. When the circuit is open, nothing returns, and the control sees a reading outside any real temperature. Rather than guess, it shows (L) (R) Evap T Open to tell you the sensor, connector or wiring on that side is not delivering a signal.
Likely causes of (L) (R) Evap T Open
- A connector at the evaporator thermistor that has loosened or been damaged
- An evaporator sensor that has failed open
- A broken or stretched wire in the sensor harness
Can you keep using the freezer with (L) (R) Evap T Open?
The freezer will generally keep cooling with this message showing, so you do not need to empty it at once. Because the control is missing a coil reading, watch the storage temperature with a freezer thermometer over the next day. If you see thawing, frost piling up or hear unusual noise, shift items to a backup freezer and follow USDA and FDA guidance. Switch the unit off at the breaker if you smell burning.
What you can safely check
- Disconnect the freezer from its outlet and leave it off for roughly a minute.
- Note on the display whether the L or R side is named.
- Check that nothing is pressed against the back wall of that side, which could strain a wire.
- Once running, watch for the message to return. If it does, do not remove the interior panels; call us.
What our technician does for (L) (R) Evap T Open
- Check the evaporator thermistor connector on the named side
- Measure the thermistor resistance to confirm an open reading
- Inspect the harness for breaks, pulling or chafing
- Replace the sensor or repair the wire
How to keep (L) (R) Evap T Open from coming back
- Keep the freezer interior organized so items do not press on the back wall where wires run
- Avoid moving the unit by pulling on panels or the door
- Have loose connectors checked early so they do not wear into a broken wire
Technical reference
- Code
- (L) (R) Evap T Open
- Appliance
- U-Line freezer
- Control family
- U-Line freezer with left and right evaporator thermistors
- Maker documentation
- U-Line owner manuals and support
- Checked
- November 2026
Code meanings come from the maker’s documentation and our own repair work; we do not reprint the maker’s document. Confirm the full model number before acting on a code. We are an independent repair company, not affiliated with U-Line Corporation.
Related U-Line freezer error codes
(L) (R) Evap T Open questions
What does the evaporator thermistor do in a freezer?
It measures how cold the evaporator coil is. The control uses that reading to manage cooling and to know when a coil that has frosted needs attention.
Why does the code show both (L) and (R)?
The display text carries the side marker for either zone. Look at which side the message names, since that is where the sensor circuit is open.
Is my frozen food in danger because of this message?
Not necessarily, since the freezer may still cool. Check with a freezer thermometer, and follow USDA and FDA guidance if the temperature rises.
How is (L) (R) Evap T Open different from the Zone T message?
The evaporator sensor sits on the cold coil, while the zone sensor measures air in the storage space. Both can be open, but the codes tell the technician which sensor to test first.
Will a restart clear (L) (R) Evap T Open?
A short power reset can remove the message if the connector reseated itself. If the circuit is truly open, the control finds it again and the message returns.
Need help with (L) (R) Evap T Open?
A technician finds the cause at your bar or lanai and puts the price in writing before any part comes out.