The situation when upper chamber of the refrigerator suddenly stops cooling food can take you by surprise and lead to inventory damage. This usually happens gradually: first the ice disappears, then the food becomes warm, and eventually the compartment reaches room temperature. Understanding why this happened requires an analysis of the operation of the entire refrigeration system, since the upper compartment often depends on the circulation of cold from the lower freezer.
In most modern models, be it Indesit, LG or Atlas, cold air is produced an evaporator located in the freezer and forced upward by a fan through special channels. If the upper chamber does not freeze, but the lower one is working properly, the problem most often lies in a disruption of this circulation, malfunction of the sensors or depressurization of the system. It is important not to panic and carry out consistent diagnostics to determine whether you need to call a technician or whether the problem can be fixed yourself.
The first thing to do when a malfunction is detected is to assess the scale of the problem. Check if the light is on, if you can hear the sound of the compressor running, if there is any extraneous noise or its complete absence. If the compressor hums, but does not start or runs endlessly without shutting down, but there is no cold, this is a sign of a serious breakdown that requires professional intervention. However, in many cases the reason turns out to be trivial and easily eliminated.
Checking the thermostat and temperature settings
The simplest and most common reason why the upper compartment stops working is due to incorrect settings or a malfunction of the thermostat. In refrigerators with mechanical control, this may be a shift in the control knob, and in electronic models, a software failure or sensor failure. If the thermostat is “stuck” in the “Off” position or shows incorrect data, the compressor simply does not receive a signal to start.
It is necessary to check the set temperature regime. For normal functioning of the upper chamber, the temperature must be set in the range from +2 to +5 degrees Celsius. If the control is set to minimum cooling, food may begin to spoil. In models with electronic control, you should try to reboot the system by disconnecting the device from the network for 10-15 minutes.
- 🔍 Check the position of the thermostat knob - it should not be moved to the extreme position.
- 🌡️ Make sure that the temperature sensor is not blocked by food or containers.
- 🔄 Try changing the settings and listen for the compressor to start after a few minutes.
Sometimes the problem lies in the thermostat mechanism itself, which does not physically close the contacts when the temperature rises. In older models, this is solved by replacing the part, which an experienced home craftsman can do. In modern systems with No Frost electronic sensors are responsible for this, the diagnosis of which requires a multimeter.
⚠️ Attention: If after adjusting the thermostat the refrigerator starts working, but after a while it stops freezing again, the thermostat is probably faulty and requires replacement, since it does not correctly read the temperature inside the chamber.
Problems with the air supply damper and freezing
In refrigerators of the system No Frost and “Crying Evaporator”, cold is supplied to the upper chamber through a special channel equipped with an air damper (damper). This damper opens and closes automatically to regulate the flow of cold air. If the mechanism is stuck in the closed position or is frozen, the circulation stops and the upper chamber stops cooling, remaining warm.
A frequent cause of the damper blocking is the formation of an ice plug in the channel. This may occur due to a door that is not closed tightly, frequently opened, or a faulty defrost system. Ice blocks the path of air, and even a properly working fan will not be able to supply cold to the upper compartment. This can be visually noticed by the presence of frost or ice around the air duct opening.
To eliminate the problem, complete defrosting of the refrigerator is often required. It is necessary to disconnect the device from the power supply, empty the chambers of food and leave the doors open for at least 24 hours. Only complete thawing will remove ice plugs in hard-to-reach channels that are invisible to the eye.
☑️ Checking the defrosting system
If after defrosting the problem returns after a few days, it means the defrosting system is broken. In this case, the evaporator becomes clogged with ice and the damper is blocked again. A check of the defrost heating element, timer or defrost sensor is required.
Fan and circulation system malfunctions
The key element that ensures the operation of the upper chamber in refrigerators No Frostis the fan. It is he who drives cold air from the evaporator located in the freezer through the air ducts into the refrigerator compartment. If the fan stops, breaks down, or its blades are blocked by ice, circulation stops instantly.
You can diagnose the operation of the fan by ear. When you open the door of the refrigerator compartment (in some models you also need to open the freezer), you should hear the characteristic noise of the motor running. If there is silence, although the compressor is humming, the fan motor may have burned out or there is no voltage being supplied to it. Also, the blades may be blocked by ice, which often happens when defrosting fails.
In some cases, the fan works, but blows weakly. This may indicate worn bearings or contamination of the axle with dust and grease deposits. Cleaning and lubrication can temporarily extend the life of the unit, but it is better to replace it with a new one to avoid repeated overheating and shutdown.
- 🔊 Open the door and listen to see if the fan is working.
- ❄️ Check if ice is interfering with the rotation of the blades.
- 🔌 Call check the motor winding with a multimeter to check for a break.
Replacing a fan is usually not difficult. It is located behind the back wall of the freezer. When installing a new part, it is important to make sure that the connectors are connected correctly and the wires are not pinched by the housing.
Refrigerant leak and problems with the compressor
A more serious reason why the upper chamber does not freeze is a freon leak or a compressor malfunction. Unlike problems with the damper, here the cold disappears in the entire refrigerator, but due to design features (the evaporator is often located at the bottom), the cold can stay in the freezer longer, creating the illusion of its normal operation.
If there is a refrigerant leak, the compressor works almost non-stop, trying to gain temperature, but there is no cold or it is very weak. The condenser (grid at the back) may be barely warm or cold, although it should be hot. If the compressor is hot, but does not start or hums and clicks, the motor may be jammed or the start relay has burned out.
It is impossible to fix the leak or replace the compressor yourself without special equipment and skills. You need to call a technician who will pressure test the system, find the leak, seal it, replace the filter drier and fill the refrigerator with new freon.
Symptoms of a freon leak
If you notice that the refrigerator works constantly without turning off, and there is no frost on the back wall inside the chambers or it appears only in shreds - this is a sure sign lack of refrigerant. A specific smell may also appear if the leak occurs in the foamed part of the housing.">
Clogged capillary tube and filter-drier
Another technical malfunction leading to a lack of cold in the upper chamber is a clogged capillary tube or filter-drier. Oil and refrigerant circulate inside the system, and Over time, oxidation products or moisture can accumulate in the filter, turning into an ice plug (if there is a lot of moisture) or solid sediment.
If the refrigerator is partially clogged, it may freeze, but not reach the desired temperature, working in intensive mode. If the freon is completely clogged, the circulation of freon stops completely, but the evaporator remains cold only at the beginning of the cycle or does not get cold at all. This is often accompanied by a dull hum from the compressor.
To eliminate the blockage, it is necessary to purge the system with nitrogen under high pressure and replace the filter-drier. This procedure can only be performed by a qualified specialist using professional equipment. Attempts to clean the system yourself can lead to ruptured tubes or damage to the compressor.
Fault diagnosis table
To quickly determine the cause of a breakdown, use the summary table of symptoms. It will help you figure out which part to check first and whether you should count on self-repair.
| Symptom | Probable cause | Difficulty of repair | Do you need a technician |
|---|---|---|---|
| The compressor does not turn on, silence | The thermostat or start relay is faulty | Low | No (you can do it yourself) |
| Humming, but not freezing, warm grill | Freon leak or blockage | High | Yes (required) |
| The freezer is freezing, the top is warm | The fan does not work or damper | Average | Desirable |
| Frost on the back wall, then disappears | Problems with the defrost system (heating element, sensor) | Average | Yes (a tester is needed) |
| The compressor is hot, clicks and turns off | The compressor is jammed or the relay is burned out | High | Yes |
Symptom analysis saves time and money. If the problem clearly indicates a complex breakdown associated with a sealed circuit, it is better not to waste time on disassembly, but to immediately contact service.
⚠️ Attention: Never try to break through the ice plug in the channel with sharp objects (knife, screwdriver). This can lead to a puncture of the evaporator and an immediate leak of freon, which will turn a simple repair into an expensive replacement of the entire evaporator.
When you need to call a specialist
Despite the desire to save money, there are situations where self-repair is not only ineffective, but also dangerous. If diagnostics show a refrigerant leak, specialized equipment for evacuation and charging is required. A technician is also needed if the compressor itself has failed - replacing it requires soldering tubes and fine-tuning the system.
In addition, if the refrigerator is under warranty, any independent intervention, removing seals or disassembling components will lead to loss of the manufacturer's warranty. In this case, the only right decision would be to contact an authorized service center.
It is also worth considering that modern refrigerators are full of electronics. Errors in the control board can simulate mechanical failures. To diagnose electronic modules, you often need to connect to a service computer or use a special tester, which only professionals have.
Frequently asked questions (FAQ)
Why does the upper chamber not freeze, but the lower one works?
Most often this is due to impaired air circulation. In refrigerators No Frost the cold is created in the freezer and supplied to the top. If the duct is clogged, the fan does not work or the damper is closed, the cold does not reach the upper chamber. A partial leak of freon is also possible when the cold reserve is only enough for the freezer.
How long does it take to defrost the refrigerator to remove the ice plug?
To completely defrost the ice in the hidden channels and on the evaporator, it is recommended to turn off the refrigerator for at least 24 hours. Defrosting for 2-3 hours often removes visible ice, but does not eliminate blockages deep in the system, so the problem can quickly return.
Is it possible to operate a refrigerator if the upper chamber does not freeze?
Short-term - yes, if you transfer perishable food to a working freezer or other place. However, long-term operation with a malfunction (especially if the fan does not work or there is a leak) can lead to overheating and failure of the compressor, which will significantly increase the cost of repairs.
How to check if the thermostat is working?
The simplest way is to close the thermostat contacts directly (by disconnecting the refrigerator from the network!). If the compressor starts working after being plugged in, it means the thermostat is faulty. However, for accurate diagnostics, it is better to use a multimeter, checking the “continuity” of the contacts when the temperature of the sensor changes.