The situation when food turns to stone in the lower chamber, and the upper part of the refrigerator barely keeps milk warm, is one of the most common and alarming for owners of household appliances. This phenomenon often takes you by surprise, because visually the unit can work quietly, the compressor hums, and the light bulb inside is on. However, the absence of cold in the upper compartment is a direct signal that the refrigerant circulation cycle is broken or the control system settings are lost.
In most modern models, especially those equipped with the system No Frost, the cold is generated in the freezer compartment, and then the fan is forced into the refrigerator compartment. If this process is disrupted, the temperature on the shelves begins to rise, which can lead to food spoilage. It is important not to panic, but to consistently analyze possible causes, ranging from simple operating errors to complex technical malfunctions.
Understanding the operating principle of your model Indesit, LG or Atlant will help you localize the problem faster. In some cases, it is enough to simply defrost the unit, in others, you will need to call a technician to charge it with freon. Let's look in detail at why this temperature imbalance occurs and what you can do on your own.
The main reasons for the lack of cold in the upper chamber
The first thing that comes to mind when a problem is detected is a compressor breakdown. However, if the lower part freezes properly, then the motor-compressor is functioning. The problem lies in the distribution of cold. In refrigerators with one compressor and one cooling circuit, the refrigerant first passes through the freezer, releasing some of the cold there, and then enters the evaporator of the refrigerator compartment. If an obstacle or leak occurs along this path, the upper chamber stops cooling.
Often the culprit is a violation of the tightness of the system. Even a microscopic hole in the tubes of the evaporator or condenser leads to a gradual release of freon. Refrigerant evaporates, and its pressure is not enough to “finish” the cold to the upper shelves. In such cases, the freezer still works by inertia or due to residual pressure, but the refrigerator can no longer cope.
Another common reason is a clogged capillary tube. An ice plug may form inside the circulation system or oil and freon oxidation products may accumulate. This creates a barrier that physically prevents refrigerant from entering the upper chamber evaporator. As a result, the compressor works hard, trying to push gas, but the cooling capacity drops to zero precisely in the refrigerator area.
⚠️ Attention: If you hear the compressor turning on, running for several minutes and turning off, and then trying to start again, this may indicate a critically low freon level or a serious blockage. Prolonged operation in this mode is dangerous for the engine.
It is also worth considering the design features. In two-compressor models, a separate unit is responsible for each chamber. If you have just such a refrigerator, then the problem is localized exclusively in the circuit of the upper chamber: either the second compressor burned out, or its power supply circuit was broken, or there was a leak in this circuit.
Faults in the No Frost system and fan
In units with automatic defrosting, a special fan is responsible for air circulation. It is (located) behind the back wall of the freezer and drives the cold flow upward through the air ducts. If fan stops due to a motor failure or icing of the blades, the cold remains below, and warm air is at the top.
A situation often occurs when the fan is working, but the air supply channel is frozen. This happens if the defrosting system is not working correctly. The heating element No Frost may burn out, or the defrost sensor may “lie”, not giving a command to turn on the heating. As a result, a coat of ice grows on the evaporator, which blocks the air duct channels.
You can check the operation of the fan by opening the freezer door (on many models, when the door is opened, it should stop, so you need to find and press the door sensor or simply listen to the operation before opening). If you do not hear the characteristic air noise or hum of the motor, the problem may be electrical or mechanical jamming.
- ❄️ Icing of the fan blades blocks rotation.
- 🔌 Broken wiring going to the fan motor.
- ⚙️ Wear of fan motor bearings or bushings.
- 🧊 Freezing of the air channel between the chambers.
They not only interfere with circulation, but can also damage the plastic dampers that regulate air flow. If the damper is stuck in the closed position, the cold simply does not enter the upper chamber.
Why does the fan hum, but does not blow?
If you hear a hum or crackling sound, but the air does not flow, most likely moisture has entered the fan bearings, or ice has formed on the blades, which physically interferes with rotation. In rare cases, the plastic sleeve dries out and the shaft begins to dangle without creating a flow.
Problems with the thermostat and temperature sensors
Electronics are the brain of the refrigerator. They are responsible for maintaining the temperature regime thermostats (in mechanical models) or temperature sensors (in electronic models). If the sensor located in the upper chamber fails and shows the control unit incorrect data (for example, that it is -5°C, although in fact it is +10°C), the compressor simply will not turn on to cool the top.
In mechanical refrigerators, the regulator is often a bellows a tube that responds to gas expansion. If the tube bursts or loses its seal, the contacts do not close and the cooling cycle does not start. The user turns the handle, but nothing changes inside.
In modern models with a display on the door, the situation is more complicated. There may be several sensors there: one controls the evaporator, another controls the air in the chamber, and the third controls the freezer. Failure of any of them can lead to incorrect operation of the entire system. The control unit receives the signal “everything is normal” and does not give a command for cooling.
| Sensor type | Location | Fault symptom | Solution |
|---|---|---|---|
| Air sensor | In the upper part of the refrigerator compartment | The refrigerator does not turn on or works without stopping | Replacing the sensor |
| Evaporator sensor | On the evaporator (behind the back wall) | Incorrect operation of the defrost, ice | Diagnostics of the defrost circuit |
| Thermostat (mechanical) | Inside the chamber or on the body | Complete absence of cold or slight frosting | Replacing the thermostat |
| Defrost sensor | On the evaporator | Ice build-up, channel blocking | Checking the heating element and sensor |
Electronics diagnostics require special knowledge and instruments, such as a multimeter. A simple continuity test can show a break, but does not always reveal a change in resistance, which leads to errors in readings. Therefore, if you suspect electronics, it is better to contact a specialist.
Freon leakage and system clogging
This is one of the most serious technical problems. Freon is a working fluid that transfers heat. If its amount in the system decreases due to a microcrack, the pressure drops. The refrigerant boils ahead of time, before reaching the evaporator of the refrigerator compartment. As a result, the freezer is still cold (since evaporation occurs there at the beginning of the circuit), and the top is already warm.
Leaks often occur in places where tubes are soldered or in the foamed part of the body, where the heating circuit of the door perimeter passes. In older models of the “crying” type, the evaporator itself often rots, especially if it was cleaned with sharp objects. In models No Frost A leak can occur in the defrost circuit or at the point where the tubes enter the foam.
A clogged capillary tube is a “thrombus” in the circulatory system of the refrigerator. It is formed due to moisture entering the system or oil breakdown products. A characteristic sign is that the compressor runs very hot, the filter drier heats up, but there is no cold anywhere or it is very weak. Sometimes gurgling or hissing is heard.
⚠️ Attention: Self-filling with freon without evacuating the system and replacing the filter-drier is a temporary measure that will quickly lead to complete failure of the compressor. Moisture and air in the system are fatal to equipment.
To eliminate these problems, professional equipment is required: a filling station, a vacuum pump, a soldering torch. The technician must find the leak (often using a leak detector), solder it, replace the filter, and only then fill the system with gas strictly according to the scale.
The influence of the operating mode and loading of products
The reason does not always lie in a breakdown. Sometimes we ourselves create conditions under which the refrigerator cannot cope. For example, if you have loaded a large amount of warm food into the chamber, the system may not have time to cool the volume. Warm air rises, and the sensors record the high temperature, but due to the inertia of the system, the cold has not yet been distributed.
Dense loading of products also plays a role. If shelves are jam-packed and food is stacked against the back wall or blocking vents, air circulation is compromised. Cold air cannot penetrate deep into the chamber, creating “heat pockets.”
Frequent opening of doors, especially in a hot room, leads to a constant influx of moist warm air. The system No Frost begins to work hard to freeze out moisture, and the power may not be enough to maintain a low temperature in the upper zone. It is also worth checking whether food is leaning against the temperature sensor, distorting its readings.
- 🥩 Do not place hot pots inside - this will stress the compressor.
- 🌬️ Leave a gap of 2-3 cm between the food and the back wall.
- 🚪 Check the tightness of the door sealing rubber.
- 🌡️ Make sure that the refrigerator is away from the radiator and stove.
Check the settings. Perhaps one of the household members accidentally switched the temperature regulator to the “Min” or “Eco” mode, or activated the “Vacation” function, which turns off the cooling of the refrigerator compartment, leaving only the freezer to work.
☑️ Do-it-yourself primary diagnostics
When you need to call a technician: critical symptoms
There are a number of signs in which independent repair is not only useless, but also dangerous. If you see that the compressor is getting very hot (to the point where it hurts to touch), is humming louder than usual, or is constantly clicking when trying to start, this is an alarming sign. Further operation may lead to burning of the motor windings.
If you find oily spots under the refrigerator or on the rear grille, this is an almost guaranteed leak of freon along with oil. In this case, no amount of dancing with a tambourine will help, you need soldering and refueling. You should also be wary if a strange chemical smell appears inside, which was not there before.
It is important to consider the age of the equipment. If the refrigerator is more than 10-12 years old, the cost of spare parts and work to eliminate complex faults (compressor replacement, circuit re-soldering) can be 70-80% of the cost of a new unit. In such cases, it makes more economic sense to think about buying a new model that will be more energy efficient and quieter.
⚠️ Attention: Do not try to pierce the pipes or disassemble the compressor. The system contains a refrigerant that, when in contact with an open flame (cigarette, spark), can form toxic compounds (phosgene). Repairs should only be carried out by a certified specialist.
Contacting an authorized service center guarantees the use of original spare parts and compliance with repair technologies. This gives confidence that after repair the refrigerator will last a long time and will not become a source of constant problems.
FAQ: Frequently asked questions
Is it possible to use the refrigerator if the upper chamber does not freeze?
Short-term - yes, if the food does not spoil (for example, you only store drinks there). However, continuous operation in this mode is harmful to the compressor, which is working overload, trying to reach the set temperature. In addition, bacteria can multiply in a warm chamber.
Why did the refrigerator start working after defrosting, but after a week it stopped cooling again?
This is a classic sign of either a freon leak or a malfunction of the defrost system (the heating element or timer burned out). The defrosting water temporarily removed the ice blockage or allowed residual freon to circulate, but the root of the problem was not eliminated. A technician's diagnostics are required.
How much does a repair cost if you need to refill freon?
The cost consists of a technician's visit, diagnostics, the cost of gas and labor. Prices vary greatly depending on the region and refrigerator model. This is usually an average-cost service, but if you need to replace the compressor, the price will increase 2-3 times.
How to check if the thermostat is working at home?
In mechanical models, you can try closing the thermostat contacts (after disconnecting the refrigerator from the network!). If the compressor starts working after turning on and closing the contacts, it means the thermostat is faulty. But this method requires skills in working with electricians.
Does the time of year affect the operation of the refrigerator?
Yes, indirectly. In summer, when the room is hot, it is more difficult for the refrigerator to transfer heat through the condenser (rear grill). If the room is above +30°C, the refrigerator may not be able to cope with the freezer, working at its maximum capacity. In winter, on the contrary, if the refrigerator is on an unheated balcony, the oil in the compressor may thicken.