The situation when the food in the freezer is solid, and the refrigerator compartment is warm, often catches taken by surprise. Many users think that the problem lies in the thermostat, but the reality is more complicated. Malfunction of the defrost system or a refrigerant leak are the more likely scenarios. Before calling a technician, you should carry out an initial diagnosis yourself.
In modern models with the system No Frost air circulation is carried out by a fan, which drives the cold from the freezer into the main compartment. If this process is disrupted, cold air remains “trapped” below. In two-compressor units the situation is different: there, each compartment has its own compressor, and the breakdown of one of them does not affect the operation of the other. Understanding the structure of your equipment is the first step to solving the problem.
You should not ignore the first signs of a temperature violation. If you notice that the milk is souring faster than usual, and ice has appeared on the walls, this is a signal of a failure. In some cases, simple defrosting helps, but if 10-12 hours after switching on the problem returns, it means there is a technical fault. Below we will look at the main reasons why refrigerator stopped cooling, while maintaining the functionality of the freezer.
Freezing of the defrost system and clogged air ducts
The most common reason why the freezer works, but the refrigerator does not - this is the formation of an ice plug in the defrost system. In models with No Frost, the evaporator is hidden behind the back wall. It must be thawed periodically thanks to the heating element. If the heating element burns out or the defrost sensor “fails,” ice builds up and blocks the channels through which the fan should supply cold air to the upper chamber.
Visually, you may not notice the ice, since it is located inside the housing. However, an indirect sign is the hum of the fan or its complete silence. Ice can block the blades, stopping circulation. In this case the temperature in the refrigerator compartment rises to room temperature while the freezer continues to freeze, since the evaporator is located there.
⚠️ Attention: If you hear a strange cracking or buzzing sound from the back wall, do not try to break the ice with a knife or sharp objects. This will lead to depressurization of the system and expensive repairs.
To solve the problem, complete defrosting of the unit within 24 hours is often required. This will allow the ice to melt naturally. If after switching on the equipment worked normally, but a week later the situation repeated itself, it means that one of the elements of the defrosting system has failed: the heating element, sensor or timer. Independent replacement of these parts requires disassembling the rear panel and skills in working with a multimeter.
☑️ Diagnostics of the defrost system
Leakage of refrigerant (freon) in the system
The second most popular reason why the refrigerator does not It's freezing, it's a banal freon leak. The gas circulates in a closed loop, but over time, microcracks may form in the soldering areas or in the foamed part of the housing. Freon evaporates, and its pressure is not enough to cool the entire volume of the chambers. Since the freezer is smaller in volume and the evaporator is located there, it is still able to keep minus, and in the refrigerator compartment the temperature no longer drops below +10...+15 degrees.
It is difficult to determine a leak visually. It is often accompanied by swelling of the inner wall or the appearance of rust on the outer heating circuit of the door perimeter. If your refrigerator works non-stop, trying to reach the temperature, but cannot do so, this is a sure sign of a lack of refrigerant. The compressor in this mode wears out and can burn out.
Refilling with freon is not just “topping up gas.” The technician must find the leak, fix it, and only then refill the system. If you simply add refrigerant, after a short time it will come out again through the same crack. Therefore, if you suspect a leak, independent actions are pointless and even harmful.
Is it possible to drive with a freon leak?
Technically, the refrigerator will work, but the compressor will turn on constantly, trying to compensate for the lack of cold. This will cause it to overheat and fail in 2-4 weeks. In addition, the food in the refrigerator compartment will begin to deteriorate, creating a risk of poisoning.
The cost of repairs involving leak detection and refilling is usually high, as it requires special equipment and time. In older models, where the tubes are built into the housing, repair may not be economically feasible. In new units, it is often possible to solder the leak point, if it is accessible.
Compressor malfunction: one or two?
The design of the compressor unit directly affects the nature of the failure. In two-compressor models, a separate motor is responsible for each compartment. If the freezer is cold, but the refrigerator is not, then it is the compressor of the refrigeration chamber that has failed. This simplifies diagnostics: one motor hums and vibrates, the second is silent or clicks, trying to start.
In single-compressor models there is one motor, and it serves both circuits. Here the situation is more complicated. If the compressor is running, but there is no cold anywhere or only in one compartment, the problem may be in the solenoid valve. This electromagnetic switch directs freon to either one circuit or the other. If the valve is stuck in the “freezer” position, the upper chamber will remain warm.
| System type | Failure symptom | Probable cause | Difficulty of repair |
|---|---|---|---|
| One compressor | The freezer is freezing, the refrigerator is warm | Capillary clogged, leakage, valve malfunction | High |
| Two compressors | One finish is not cold | The motor-compressor of this department has burned out | Average |
| No Frost | Heat or uneven cold everywhere | Defrost failure, fan failure | Average |
| Drip | Ice on the back wall, no cold | Thermostat malfunction or leakage | Low/Medium |
Diagnostics of the compressor often requires measuring the current consumption and pressure in system. If the engine hums but does not start, the piston group may be jammed or the start relay may be faulty. In this case, replacing the relay can revive the old one refrigerator without replacing an expensive unit.
Problems with the thermostat and sensors
The “brain” of the refrigerator is the thermostat (in mechanical models) or electronic temperature sensor (in models with display). If this element transmits incorrect data about the temperature inside the chambers, the compressor may simply not turn on, believing that the cold has already been gained. Although more often than not, if the thermostat breaks down, the refrigerator either does not turn off at all or does not turn on at all, in some scenarios the readings may become desynchronized.
In modern models with electronic control, several sensors are responsible for the temperature: air in the chamber, evaporator, defrost. If air sensor in the refrigerator compartment it “lies” and shows that it is +2°C, although in fact it is +15°C, the controller will not give the command to cool. The freezer can operate according to its own cycle or be cooled by residual cold.
You can check the mechanical thermostat by closing its contacts. If the compressor starts working after closing, it means the regulator is faulty and requires replacement. It is more difficult with electronic sensors: their resistance changes depending on the temperature, and to check you need a multimeter and a table of resistances for a specific model refrigerator.
⚠️ Attention: When replacing the thermostat, it is important to correctly install the sensitive element (bellows) in the seat. Inaccurate installation will lead to incorrect operation of the equipment even with a new part.
Often users themselves change the settings by accidentally touching the regulator. Make sure that the wheel is not set to minimum, and in electronic models the “Vacation” or “Eco” mode is not activated, which can limit the cooling of the upper chamber to save energy.
Clogged capillary tube
The capillary tube is the thinnest channel through which freon enters the evaporator. Its diameter is extremely small, so even a microscopic piece of debris remaining after poor-quality repairs, or moisture that has turned into an ice plug, can block the flow of refrigerant. As a result, the pressure in the system drops, and the freon does not reach the evaporator of the refrigeration chamber, remaining in the condenser or the initial sections of the circuit.
Symptoms of a blockage are similar to a leak: refrigerator it works, but does not freeze. However, there is a difference: if clogged, the compressor may operate more quietly or, conversely, overheat, and the condenser (grid at the back) will only be partially hot. Often, when there is a blockage, you can hear gurgling or hissing, which should not normally be present.
Removing a blockage is a complex technical procedure. The technician needs to pressurize the system with nitrogen under high pressure or use a special cleaning fluid. In some cases, it is necessary to replace the filter-drier, which is supposed to trap debris, but could itself become clogged. It is impossible to carry out this operation independently without a vacuum pump and a pressure gauge station.
Why it is important to consider the type of defrosting
Understanding the operating principle of your equipment helps to narrow down the scope of troubleshooting. In systems Direct Cool (drip) water flows down the back wall, and if it is frozen in the form of a fur coat, thermal conductivity is disrupted. In the system No Frost ice forms on a hidden evaporator, and the problem is most often in the fan or heating element.
In refrigerators with a “crying” wall, a common reason that the upper chamber does not cool is the freezing of the melt water drainage channel. The water freezes, rises higher and blocks the exit of cold air. In this case, it is enough to defrost the unit, but you need to find the reason why the water did not drain (dirt, tilt of the body).
Models with a “zero temperature” or “freshness” zone have their own nuances. There may be separate dampers controlled by servo drives. If the damper is stuck in the closed position, no cold will flow into this compartment, although the rest of the refrigerator will work properly. This often happens when crumbs or ice get into the damper mechanism.
Why did the refrigerator work after defrosting, but after a week it stopped again?
This is a classic sign of a malfunction of the defrost system. Defrosting removed the ice plug, and the cold entered the chamber again. But since the heating element, sensor or timer did not work, the ice accumulated again within 5-7 days and blocked the channels again. The faulty part needs to be replaced.
Is it possible to use the refrigerator if the freezer is working but the upper chamber is not?
Short-term - yes, if you store products there that do not require strict cold (vegetables, drinks). However, the compressor will work overload, trying to gain temperature, which will shorten its life. In addition, bacteria multiply quickly in a warm chamber.
How long does it take to defrost the refrigerator for testing?
It takes at least 24 hours for the ice in the hidden channels and on the evaporator to completely melt. Defrosting for 2-3 hours is often insufficient, since the ice in the depths of the case does not have time to turn into water.
Does the amount of food affect the operation of the refrigerator?
Yes, but indirectly. An empty refrigerator loses cold faster when the door is opened. However, if the system is working properly, it will compensate for this. If the refrigerator is so jam-packed that the air ducts are blocked, the cold will not circulate, and there will be heat in the upper part.
What to do if the refrigerator has an error on the display?
Modern models display error codes (for example, F5, E1). The decoding must be found in the instructions for the specific model refrigerator. The code will indicate a specific component: sensor, fan or control board, which will simplify repairs.