The situation when the refrigerator LG suddenly stops the upper chamber cools, while the lower one continues to operate as normal, is familiar to many owners of modern equipment. This is especially alarming, given that most models of the Korean brand are equipped with a system that should ensure uniform distribution of cold throughout the entire volume. Users often notice that food in the freezer remains hard, but in the refrigerator compartment the temperature rises to room temperature, which creates a risk of food spoilage. No Frost, which should ensure uniform distribution of cold throughout the entire volume. Users often notice that food remains hard in the freezer, but the temperature in the refrigerator compartment rises to room temperature, creating the risk of food spoilage.
There can be many reasons for this behavior: from a simple clogged drainage channel to a serious refrigerant leak or failure of electronics. It is important not to panic and consistently rule out simple faults before calling a technician. In 80% of cases, the problem lies in impaired air circulation or freezing of the evaporator, and not in a breakdown of the compressor. The following text will help you carry out an initial diagnosis and understand the scale of the disaster.
Before disassembling the unit, you should make sure that the problem is not caused by external factors. Check whether the door closes tightly, whether the seal is stuck, and whether the refrigerator is too close to the wall. Sometimes it is enough to simply defrost the device for a day to restore normal operation if the cause is ice jam.
The principle of operation of the LG cooling system and the role of TWIN Cooling
To understand why the heat became in the upper chamber, it is necessary to briefly consider the design of refrigerators LG. Unlike older models, where cold air fell down naturally, modern units use forced circulation. The key element here is the system TWIN Cooling (or its variations such as Multi Air Flow), which involves the presence of separate evaporators or a complex system of dampers for each chamber.
Cold air is generated in a hidden compartment, usually located behind the back wall of the freezer, and is supplied upward through special channels. The fan and damper system are responsible for this process. If the top chamber is not freezing, it often means that the cold flow is simply not reaching its destination. A mechanical obstruction or failure of the control electronics blocks the air supply, leaving the products to warm up.
⚠️ Attention: In models with the system Linear Inverter Compressor operation algorithms may differ from classic step compressors. Do not try to reset the electronics unless necessary, as calibrating the inverter is a complex process.
A leaky circuit or dirty filters can also throw off the temperature balance. The system No Frost requires free space for the movement of air masses. If you overload the shelves and close the outlet openings, circulation will stop and the temperature sensors in the upper compartment will no longer detect cold, although the unit itself will work for wear.
The main reasons for the lack of cold in the upper compartment
If defrosting for 10-12 hours did not help, you will have to look for a deeper fault. Most often, owners are faced with the failure of one of the key components of the system. Below is a list of the most likely culprits of the problem, arranged in descending order of frequency of occurrence.
- ❄️ Fan malfunction: The impeller could become jammed with ice or the motor could burn out, causing air to stop being pumped into the upper chamber.
- 🚪 Failure of the air damper (Damper): The mechanical valve that regulates the air flow could get stuck in the closed position or its electric drive fails.
- 💨 Leakage freon: If there is little refrigerant in the system, its pressure is only enough to cool the evaporator in the freezer, but the cold no longer reaches the top.
- 🧊 Evaporator freezing: A malfunction of the defrost system (heating element, timer or sensor) led to ice completely blocking the air duct channels.
The problem with control moduleis especially worth mentioning. The electronics may “glitch” and not send a signal to open the damper or turn on the fan, even if the components are physically working. In such cases, a reboot often helps, but if there is an error in the firmware or the triac on the board is burned out, components will need to be replaced.
Mechanical damage also cannot be ruled out. For example, if you recently washed or moved the refrigerator, the air supply pipe may have become damaged or the temperature sensor may have become dislodged. Carefully inspect the insides of the chamber for visible defects in the plastic elements.
Diagnostics of the defrost and fan system
The most common reason why LG stops freezing on top when the freezer is running is “slush” (snow porridge) in the channel evaporator. The defrost system must periodically turn on the heating element to melt ice on the radiator. If the heating element is burned out or the defrost sensor is “lying,” ice builds up and eventually blocks the path to air.
To check, you need to get to the evaporator. In most models LG to do this you need to remove the back panel in the freezer. If you see a thick layer of ice covering the entire radiator and fan, the defrost cycle is broken. In such conditions, the fan either does not spin at all, or hums, trying to break through the ice plug, but does not pump air.
☑️ Checking the defrost system
The fan is checked visually and by ear. When the freezer door is open (and the door sensor is pressed, if there is one), the fan should work. If it is silent, rotate the blades by hand - if there is jamming, it means that moisture or dirt has entered the bearing. If the fan makes noise but does not blow, most likely the motor winding has burned out.
⚠️ Attention: When checking electrical components (heating element, fan, sensors), be sure to unplug the refrigerator! Using a multimeter under voltage is dangerous to life and can damage the control board.
If the defrosting system is working properly, but the cold is still not coming out, check the condition of the air damper. It is located on the border between the freezer and refrigerator compartments. In some models LG this is simply a mechanical curtain, in others it is a motorized valve. Make sure it is not blocked by pieces of ice or fallen food.
Freon leakage: symptoms and detection methods
Refrigerant leakage is a more serious problem that requires professional intervention with the equipment. Freon circulates in a sealed circuit, and if a micro-hole has formed somewhere (often due to corrosion or a manufacturing defect), the gas gradually evaporates. A characteristic symptom: the freezer still somehow keeps minus, but the upper chamber is already warm, and the compressor works almost without stopping.
How to determine a leak yourself? Carefully inspect the inside of the freezer and the rear of the refrigerator. Look for traces of oil. Freon circulates along with compressor oil, so a greasy stain often remains at the leak site. Also, uneven ice may appear on the evaporator: for example, only at the entrance of the tubes, and the rest of the radiator is dry and warm.
If you hear a hissing sound when the compressor is running or notice that the condenser (the grille at the back or the side walls) remains cold, although the engine is humming, this is a sure sign of a lack of gas. It is impossible to refill the refrigerator yourself; the system must be evacuated and charged with a strictly defined type and weight of refrigerant.
Is it possible to drive with a freon leak?
You can drive, but not for long. Operating a compressor without a sufficient amount of freon (which is also a refrigerant for oil) leads to overheating and rapid wear of the piston group. It is better to turn off the device before the technician arrives.
Problems with the air damper and temperature sensors
In modern models LG with electronic temperature control, a special damper (air damper) is responsible for the supply of cold. This is a servo-driven damper that opens and closes on command from the main processor. If the mechanism is stuck in the closed position, cold air physically cannot enter the refrigerator compartment, even if there is a snowstorm in the freezer.
Diagnostics of the damper often requires disassembling the upper part of the refrigerator compartment. You need to check whether voltage is coming to the damper motor. If there is voltage, but there is no movement, the motor has burned out. If there is no voltage, the problem is in the control board or wiring. It often happens that the plastic curtain itself or its axis breaks.
Do not forget about temperature sensors (thermistors). In refrigerators LG there are usually several of them: one in the freezer, one in the refrigerator, one on the evaporator. If the sensor in the upper chamber gives incorrect readings (for example, it “thinks” that it is -5°C, although in fact it is +15°C), the controller simply will not open the damper, believing that there is no need to cool.
| Symptom | Probable cause | Actions |
|---|---|---|
| The freezer is working, the top is warm, the compressor is constantly humming | Freon leakage or capillary clogged | Call a technician to find a leak and refill |
| There is a coat of ice in the freezer, the top is not cold, the fan silent | Malfunction of the defrost system (heating element, timer) | Replacement of the evaporator heating element or defrost sensor |
| There is cold, but weak, a whistle or hum is heard | Fan clogged or geometry violation air duct | Cleaning the fan, checking the tightness of the channels |
| The temperature fluctuates, errors appear on the display | Faulty sensors or control board | Diagnostics of thermistors with a multimeter, reset errors |
When you need to call a professional technician
Despite the desire to save money, there are situations when independent refrigerator repair LG is not only useless, but also dangerous. If diagnostics indicate a problem with a sealed circuit (leakage, clogged capillary tube), you cannot do without a specialized tool (vacuum pump, pressure gauge station, scales). Homemade methods of “puncture” often lead to the final death of the unit.
You should also contact a specialist if the inverter compressor has failed. These components are very sensitive to operating conditions and require specific knowledge for replacement and subsequent adjustment. If you try to replace the compressor yourself, you risk getting a new unit that will burn out in a week due to improper soldering or contamination of the system.
In addition, if after defrosting and checking the fan the problem does not disappear within 24 hours, further experiments may lead to food damage. Professional diagnostics takes about 30-40 minutes and gives an accurate answer whether it is worth repairing a specific unit or whether it is easier to replace the entire unit.
Why, after defrosting, did the LG refrigerator stop freezing again after a week?
This is a classic sign of a malfunction of the defrost system. You removed the ice manually, but the reason for its appearance (a burnt-out heating element, timer or sensor) has not gone away. Within a week, new ice clogged the evaporator again. The defective element of the No Frost system needs to be replaced.
Is it possible to temporarily use the refrigerator if the top does not freeze?
It can be used, but with restrictions. Perishable foods cannot be stored in the upper chamber. The compressor will work harder, trying to cool the volume, which will lead to increased electricity bills and wear on the motor. It is recommended to minimize door opening.
What does the ER FF error mean on an LG refrigerator?
Error ER FF (or ER FF) indicates a malfunction of the freezer fan. It is this node that is often responsible for supplying cold to the top. Check to see if the fan is frozen in ice, or replace it if the motor is burned out.
How to properly defrost an LG refrigerator with No Frost?
Disconnect the appliance from the power supply, open all doors. Leave it for at least 12-24 hours. Do not use a hairdryer or hot water to speed up the process - sudden temperature changes can damage the plastic and evaporator tubes. Place rags to catch the draining water.