The situation when the refrigerator compartment is warm, but the freezer compartment continues to work, is a classic symptom for two-chamber refrigerators of the brand LG. This indicates that the compressor is working properly, the refrigerant circulation system is not globally damaged, but a failure has occurred in the cold distribution unit. Most often, owners encounter this after they notice that the food in the upper compartment has stopped cooling, although the light is on and the fan is humming.
The main problem lies in the disruption of cold air circulation or in the incorrect operation of the system. No Frost. Unlike older models with a drip system, modern units LG rely on the precise operation of electronics and damper mechanics. If you hear the hum of the motor, but there is no cold, it means that cold is physically produced, but simply does not get into the desired compartment.
Diagnostics should begin with simple steps that do not require disassembling the equipment. Often the cause is a simple overload of products blocking the air channels, or a failure in the control board software. However, ignoring the problem can lead to spoilage of products and failure of more expensive components, such as compressor.
The principle of operation of the air distribution system
In refrigerators LG with technology Total No Frost cold air is generated in the freezer compartment and is forced into the refrigeration compartment through special channels. evaporator i fanis responsible for this process. If the freezer is working, then the evaporator is cold, and the compressor performs its function of compressing the refrigerant.
The key element here is damper air supply. This is a mechanical damper with an electric drive that opens according to a signal from the thermostat, allowing cold to enter the upper chamber. When the temperature reaches the set values, the damper closes. If this mechanism is stuck in the closed position or its motor is burned out, the air simply stops flowing, leaving the food warm.
The defrosting system also plays an important role. If a layer of ice builds up on the evaporator in the freezer due to a malfunction of the defrost heating element or timer, the air passage is blocked by ice. The fan continues to hum, but it cannot push air through the ice plug. In this case, the freezer can work, but the cooling efficiency drops sharply, and the cold does not reach the upper compartment.
⚠️ Attention: An attempt to forcibly open the damper or pick at the ice with a knife can lead to damage to the plastic elements and depressurization of the cooling system.
Independent diagnostics and initial check
Before calling a technician, you need to carry out a number of checks that will help localize the problem. Often, users do not notice that the operating mode has been accidentally changed or the door is not closed tightly. First of all, check the tight fit sealing rubber along the entire perimeter of the refrigerator door.
If the rubber is in order, listen to the operation of the unit. In a working refrigerator LG you should hear the periodic hum of the fan and clicks of the damper. If the chamber is quiet even though the compressor is running, the air duct may be clogged. Products should not lie close to the back wall where the outlet openings are located.
Try to perform reboot control systems. The electronics may have gone wrong, and a simple power reset will help restore the factory settings. Unplug the refrigerator for 15-20 minutes, then turn it on again. If the cold appeared after a couple of hours, the problem was a software failure.
It is important to check if the “Super Freeze” or “Vacation” mode is turned on if it affects the operation of the upper chamber in your model. The display can indicate which functions are active. It is also worth inspecting the back wall inside the chamber: if it is unevenly covered with frost or ice, this is a sign of poor circulation.
Main causes of malfunction and error codes
Modern refrigerators LG are equipped with a self-diagnosis system that displays error codes on the display. These codes greatly simplify troubleshooting. If you see flashing indicators or alphanumeric combinations, you need to decipher them.
The most common reasons why the refrigerator does not freeze, but the freezer works:
- ❄️ Damper malfunction: the damper is stuck closed or the drive is burned out.
- 🌡️ Temperature sensor failure: the sensor erroneously sends a signal that it is cold in the chamber and does not open the damper.
- 🧊 Freezing evaporator: a malfunction of the defrost system (heating element, timer, thermal fuse) led to an ice plug.
- 💨 Fan failure: the motor is spinning, but the impeller has fallen off or become dirty, or the winding has burned out.
Let's look at the table of the main error codes typical for cooling problems in refrigerators LG:
| Error code | Description of malfunction | Probable cause |
|---|---|---|
r F |
fridge compartment error | Temperature sensor or damper faulty |
d H |
Error defrost | The defrost heating element or timer has burned out |
f F |
Freezer error | Problem with the sensor or fan |
E r FF |
Fan error | Fan jammed or broken circuit |
If a code is lit on the display r F, this is a direct indication that the control system is not receiving correct data from the refrigerator compartment. In 80% of cases this is due to temperature sensor or drive damper. Replacing these elements usually solves the problem.
What does all the indicators blink?
If all the temperature indicators are blinking, this often indicates a communication error between the main board and the display, or a serious malfunction of the compressor (inverter). In this case, professional diagnostics with a multimeter is required.
Problems with the damper and the No Frost system
The damper (damper) is a “gate” that regulates the flow of cold air. In refrigerators LG it is located in the upper part of the rear wall of the refrigerator compartment or in the partition between the chambers. The design is a plastic case with a movable curtain and a small electric motor.
Over time, the plastic can become deformed due to temperature changes, and the curtain begins to jam. The motor, trying to open the valve, hums, but the mechanism does not move. As a result, no air flows. You can check this by removing the decorative panel in the chamber (after turning off the power) and visually assessing the position of the damper when turned on.
Also, a situation often occurs when the damper is working, but the channel coming from the freezer is clogged with food or ice. In models with Multi Air Flow there may be several channels, and overlapping the main one will disrupt the temperature balance. The fan will run idle, creating noise, but there will be no cold.
Faults of sensors and thermostats
Refrigerator electronics LG entirely depends on sensor readings. If temperature sensor the refrigerator compartment “lies” and shows that there is +2°C instead of the real +10°C, the controller will not give the command to open the damper. The refrigerator will consider that the task has been completed and will save resources.
Sensors are thermistors, the resistance of which varies depending on the temperature. Over time, they can lose calibration or fail due to power surges in the network. Replacing the sensor is an inexpensive procedure, but requires access to internal wiring.
In addition, there is thermostat (mechanical in some models, electronic in most - as part of the board). If it is faulty, the compressor cycle may be disrupted. However, since the freezer is working, the compressor is working properly, so the focus shifts precisely to the sensors that control the distribution, and not the generation of cold.
⚠️ Attention: When replacing sensors, be sure to use original spare parts or high-quality analogues with the same resistance ratings. Cheap Chinese sensors can give an error of 5-7 degrees.
When professional repairs are required
Despite the possibility of self-diagnosis, there are cases when you cannot do without a specialist. If you checked the damper, sensors and fans, but the problem remains, it may be the freon leak. Although when there is a leak, the freezer usually stops freezing, in the initial stage or with a partial leak in the refrigeration chamber circuit, the pressure may drop faster.
Also complex cases include a malfunction inverter board or the main control module. If the board is “buggy” and does not supply voltage to the damper motor or fan, no amount of replacing parts will help. Re-flashing or replacement of the board is required, which requires qualification.
Another serious reason is clogging of the capillary tube. An ice or oil plug may form in the refrigerant circulation system. This disrupts the circulation of freon. In the freezer, where the evaporator is located directly, there is still cold, but it does not reach the remote chamber. Removing the blockage requires vacuuming and charging the system.
☑️ Checklist before calling the technician
Prevention and rules operation
To prevent the situation when the refrigerator does not workand the freezer is functioning from happening again, it is important to follow the operating rules. Do not place hot foods inside - this causes excessive steam formation and rapid freezing of the channels. Regularly check the cleanliness of the back wall.
Once every six months it is recommended to completely defrost the refrigerator, even if it is equipped with a system No Frost. This will help remove micro-ice build-up in hard-to-reach areas of the air ducts that the standard defrost system does not remove. This will also extend the life of the compressor.
Monitor the condition of the seals. If the gum is dry or contaminated with grease, warm, moist air enters the chamber. This leads to increased formation of ice on the evaporator and eventual airflow blockage. Wipe the seals with a soft cloth and soapy water.
Why does the refrigerator hum, but does not freeze?
Humming indicates the operation of the compressor and possibly the fan. If there is no cold, it means that the refrigerant is circulating, but does not reach the desired zone due to a closed damper, an ice plug, or a faulty sensor that does not give a command to cool.
Is it possible to operate a refrigerator with a non-working upper chamber?
For a short time - yes, if the freezer is working. However, this places increased stress on the compressor as it may be running continuously trying to reach temperature. Long-term operation in this mode reduces the resource of the unit.
How long does it take to defrost to remove the ice plug?
To completely defrost the ice in the hidden air ducts and on the evaporator, the refrigerator must be left unplugged with the doors open for at least 24 hours. A shorter defrosting may not eliminate the problem completely.
Does the voltage level in the network affect the operation of the damper?
Yes, low voltage or surges can lead to malfunctions of the electronic control module that controls the damper motor. In such cases, it is recommended to use a voltage stabilizer.