U-Line Refrigerator Error Temp Lo 12H+: Zone Too Cold
Temp Lo 12H+ shows that a zone has sat about 10 degrees F colder than the set point for more than 12 hours, a lasting overcooling condition.
What does U-Line refrigerator & drawers code Temp Lo 12H+ mean?
Temp Lo 12H+ is the extended overcooling alert from a U-Line refrigerator's digital control. It appears when a zone has remained about 10 degrees F under the set point for more than 12 hours. Half a day of overcooling is not a normal swing. Possible causes include a changed set point, a thermistor reading wrongly, or a control or damper problem that keeps sending cold air in. The zone is colder than you asked for and not correcting itself.
Temp Lo 12H+ at a glance
- Code
- Temp Lo 12H+
- Appliance
- U-Line refrigerator & drawers
- Applies to
- U-Line digital control, temperature zone
- Type
- Low urgency
- Can you clear it yourself?
- Sometimes, after the safe checks below
- Most likely cause
- A set point that was changed and never set back
What you may notice with Temp Lo 12H+
- Temp Lo 12H+ is displayed on the refrigerator
- Items in the zone have partly frozen overnight
- Ice or frost builds on shelves or containers
- The zone stays colder even after you adjust the set point
How the refrigerator & drawers detects Temp Lo 12H+
The control inside a U-Line refrigerator expects a zone to hover near its set point as cooling cycles on and off. If the zone temperature falls and stays well below target, the control starts a timer. When the cold period passes 12 hours, it escalates to Temp Lo 12H+.
The gap that triggers it is about 10 degrees F below the set point. That much overcooling, lasting half a day, tells the control that its cycling is not working. It cannot see why. A wrong set point, a sensor that misreports temperature, or a control or damper that never closes can each leave the zone stuck cold, so the order of checks matters.
Likely causes of Temp Lo 12H+
- A set point that was changed and never set back
- A zone thermistor giving a reading that does not match the true temperature
- A control or damper problem that keeps feeding cold air into the zone
Can you keep using the refrigerator & drawers with Temp Lo 12H+?
You may keep using the unit, because a cold zone is not a safety hazard. The risk is frozen produce, split bottles and extra energy use. Measure with a thermometer, correct the set point and keep fragile items elsewhere. If the zone is still freezing after you fix the setting, turn it off and arrange service.
What you can safely check
- Turn the breaker off or unplug the refrigerator before you adjust shelves or clear the vent area.
- Look at the set point shown on the control and reset it to your preferred value if it has changed.
- Make sure the door closes properly and no item presses against the vents.
- Compare a refrigerator thermometer in the zone with the display over a few hours.
- If Temp Lo 12H+ stays, call us.
What our technician does for Temp Lo 12H+
- Check the zone thermistor against a known reference
- Test the control's cooling cycle for runaway operation
- Inspect and test the damper and its motor or linkage
- Replace the part that is holding the zone too cold
How to keep Temp Lo 12H+ from coming back
- After changing a set point, note it down so an accidental change is easy to spot.
- Do not block the vents inside with tall bottles or boxes, which can confuse airflow and temperature.
Technical reference
- Code
- Temp Lo 12H+
- Appliance
- U-Line refrigerator & drawers
- Control family
- U-Line digital control, temperature zone
- 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 refrigerator & drawers error codes
Temp Lo 12H+ questions
What does Temp Lo 12H+ mean?
It means a zone has stayed about 10 degrees F under the set point for more than 12 hours. The control reports it because the zone is overcooling and not recovering.
Is Temp Lo 12H+ the same as Temp Lo 6H+?
The condition is the same, but this one has lasted twice as long. A longer duration makes a simple setting mistake less likely and a sensor or damper problem more likely.
Can I keep food in a zone showing Temp Lo 12H+?
Yes for most items, but watch for freezing. Move produce, eggs and drinks to a warmer place so they do not freeze, and use a thermometer to confirm the real temperature.
Will Temp Lo 12H+ cause damage to the refrigerator?
Overcooling is mostly a food and energy problem, not damage to the unit itself. Still, a stuck damper or runaway cooling means a part is not doing its job, so it should be tested.
What details help the repair company with Temp Lo 12H+?
Give us the exact code text, the set point you want, what a thermometer reads and whether items are freezing. Tell us if the set point changed recently, since that narrows the cause.
Need help with Temp Lo 12H+?
A technician finds the cause at your bar or lanai and puts the price in writing before any part comes out.