Most likely causes, in order
1. Ice blocking the evaporator (defrost failure)
LG refrigerators cool the fresh-food section with air that passes over the freezer evaporator. Every few hours a defrost heater melts the frost off that coil. When the heater, its sensor or its fuse fails, frost builds into solid ice, the air path to the fridge closes, and the fridge warms while the freezer stays fairly cold. Telltale signs: frost on the back panel inside the freezer, water dripping under the crispers, Er dH or Er FF codes.
2. A fan has stopped
The freezer fan (behind the freezer back panel) and on many models a separate fresh-food fan move the cold air. A fan iced in place or with a worn motor shows Er FF or Er rF. Open the freezer door, press the door switch: on most models you should hear the fan run.
3. Demo mode
If the display shows OFF or O FF and the lights work but nothing cools, the refrigerator is in demo (display) mode. It is not broken. See how to exit demo mode.
4. Condenser problems
A dusty condenser coil or a failed condenser fan (Er CF) makes the refrigerator lose its ability to shed heat — especially in a Las Vegas summer or a hot garage.
5. Compressor, inverter board or refrigerant
If both sections are warm, the compressor is the suspect. On LG linear-compressor refrigerators you may hear a click every few minutes as it tries and fails to start. A failed inverter board produces the same symptom for much less money, and a refrigerant leak causes slow, steady loss of cooling over weeks.
Safe checks you can do
- Check the display for OFF (demo mode) or an error code.
- Check the set temperatures: 37 °F fresh food and 0 °F freezer are good targets.
- Do not block the vents inside the fresh-food section; overpacked shelves stop airflow.
- Clean the condenser: unplug, remove the lower rear cover (or front grille on some models) and vacuum the coil and fan.
- Listen at the back bottom: is the compressor running? Is the condenser fan spinning?
- Look for frost on the freezer back panel. Heavy frost = defrost problem.
- Temporary fix for ice: unplug the refrigerator, prop the doors open with towels on the floor for 8–24 hours, then restart. If it cools again, the defrost system has failed and the ice will return within days to weeks.
When to stop and call
- Both sections warm and the compressor clicks or is silent.
- The ice comes back after a manual defrost.
- Any error code that returns after a 5-minute power reset.
- Food is at risk: the fresh-food section above 40 °F for more than 2 hours.
What the repair costs
| Repair | Typical total |
|---|---|
| Defrost heater, sensor or fuse | $190 – $400 |
| Freezer fan / fan-grille assembly | $180 – $360 |
| Condenser fan motor | $180 – $330 |
| Main or inverter board | $230 – $520 |
| Compressor replacement | $650 – $1,270 |
| Refrigerant leak repair | $350 – $940 |
All totals include the $75 service call. See LG refrigerator repair.
Questions about an LG refrigerator not cooling
Why is my LG freezer cold but the fridge is warm?
The fresh-food section depends on cold air from the freezer evaporator. When that coil ices over from a defrost failure, or the fan or damper stops moving air, the freezer stays cold but the fridge warms up.
How do I reset my LG refrigerator?
Unplug it or switch off its breaker for 5 minutes, then restore power. A reset clears temporary faults but does not fix ice buildup or failed parts.
How long does it take an LG refrigerator to cool after a repair?
Usually 12 to 24 hours to reach full temperature. The fresh-food section is often below 40 °F within a few hours.