The situation when the refrigerator Samsung stops maintaining the set temperature in the upper compartment is one of the most common complaints of owners. In modern models with a No Frost or Twin Cooling system, disruption of cold air circulation leads to food spoilage, although ice can form normally in the freezer. This often misleads the user: since the freezer is working, it means that the compressor is working, but the upper part remains warm.
There can be many reasons for this behavior of the equipment: from a banal blockage of the drainage channel to the failure of complex control electronics. The owner may notice that the back wall is covered with a thick layer of ice, or, conversely, is completely dry and warm. Understanding the operating principle of air ducts and sensors will help you quickly determine the scale of the disaster and decide whether to call a technician or try to fix the problem yourself.
In this article we will analyze in detail the mechanical and electrical faults that lead to a lack of cold from above. We will look at the operation defrost systems, the condition of the seals and the logic of the controller. It is important not to ignore the first symptoms, since prolonged operation in abnormal mode can lead to expensive repairs of the compressor.
Impaired air circulation and malfunction of the No Frost system
The main reason why the top of the refrigerator does not freeze Samsung, lies in the forced air circulation system. Cold air is produced in the freezer compartment and is forced by a fan through special channels into the refrigerator compartment. If this process is disrupted, the temperature above begins to rise. Most often, the problem lies in freezing of the evaporator or a breakdown of the fan itself.
In systems No Frost ice freezes on the evaporator, which is hidden behind the rear panel of the freezer. The heating element periodically turns on and thaws this ice. If the defrosting cycle is disrupted, the ice “coat” grows so much that it blocks the air ducts. As a result, the fan hums, but the air simply cannot pass through the ice plug into the upper chamber. You may hear a characteristic noise or crackling of ice while trying to break through the blockage.
Another option is failure of the unit itself fan. If its impeller is blocked by ice or the motor winding burns out, circulation stops completely. In models with a system Twin Cooling, where each chamber is responsible for its own circuit and fan, a breakdown of the top fan leads to exactly the problem described, while the freezer continues to operate normally.
- ❄️ Check whether the air duct is blocked by food or ice mass.
- 🔊 Listen to the operation of the fan: extraneous noise or its absence is a bad sign.
- 🧊 Assess the amount of ice in the freezer: excess snow indicates problems with defrosting.
Problems with temperature sensors and defrost system
Refrigerator electronics Samsung rely entirely on sensor readings. evaporator temperature sensor and defrost sensorare responsible for the defrosting and cooling process. If the evaporator sensor “lies” and shows the controller that the temperature is normal, although in fact it is warm there, the compressor simply will not turn on or will work in too short cycles. This is a common reason why the upper chamber does not have time to cool.
A malfunction of the defrost system sensor leads to the heating element not turning on on time or, conversely, heating constantly. In the first case, the evaporator becomes overgrown with ice and blocks the channels (as described above). In the second case, the system may “think” that defrosting is taking too long, and emergency stop the compressor, fearing overheating. Diagnosis of these elements requires a multimeter to check the resistance.
Also worth mentioning fridge compartment temperature sensor, which is often located inside the compartment itself. If it fails or moves out of place, the controller receives incorrect data. For example, the sensor shows +2°C, although in reality it is +10°C. As a result, the refrigerator “does not see” the need for cooling.
⚠️ Attention: When replacing sensors, be sure to use original spare parts or high-quality analogues with identical resistance. Installing an unsuitable sensor can lead to incorrect operation of the entire control system and repeated breakdown after a short time.
To check the sensors, you must gain access to the rear panel of the freezer. They are often mounted on or near the evaporator itself. Before carrying out any work on electrical components, make sure that the device is completely disconnected from the network.
How to check the sensor with a multimeter?
To check, switch the multimeter to resistance measurement mode (Ohms). The normal sensor resistance at room temperature is usually several tens of kOhms (for example, 50 kOhms). When cooling (for example, if you blow cold air on it), the resistance should change smoothly. If the device shows a break (1) or zero, the sensor is faulty.
Faults of the compressor and start relay
Although the compressor is the “heart” of the refrigerator, and its complete stop usually leads to defrosting of the entire device, there are nuances. In dual-circuit systems or models with solenoid valves, the malfunction may be partial. However, most often problems with the compressor manifest themselves in its inability to create sufficient pressure for both circuits at the same time.
If the compressor works, but does not reach the required speed (wear of the mechanical part or problems with the windings), there may be enough cold only for the freezer, which has priority in the refrigeration cycle. Also, the cause may be a faulty starting relay. If the relay is “burned out,” the compressor may hum, trying to start, but not start, or work intermittently.
In inverter models Samsung the situation is more complicated. There, an electronic control module is responsible for the operation of the motor. If the inverter gives an error, the compressor may operate in “emergency” mode with reduced power, which is not enough to freeze a large volume in the upper chamber.
Refrigerant leak and capillary system clogged
One of the most unpleasant reasons why the upper part does not freeze is a partial leak freon (of the refrigerant). Unlike a complete leak, when the refrigerator simply stops cooling, with a partial leak, there is not enough pressure to push the refrigerant through the entire circuit to the upper chamber. As a result, the evaporator in the freezer is still cold, but in the refrigerator compartment it is no longer cold.
causes similar symptoms clogged capillary tube. Oil breakdown products or moisture entering the system form an ice or dirt plug in a bottleneck in the tube. The refrigerant cannot circulate fully. A characteristic sign of a blockage is that the condenser (rear grill) may be only partially hot, and the compressor runs almost non-stop.
Diagnosing a leak or blockage at home is extremely difficult and often impossible without special tools. If you notice that the refrigerator runs for days without turning off, but the temperature above does not drop, the likelihood of a leak or blockage is very high.
| Symptom | Probable cause | Action |
|---|---|---|
| The compressor is humming, but not starts | The starting relay or compressor wedge is faulty | Replace the relay, call a technician |
| The refrigerator works without stopping | Freon leakage or system blockage | Search for leaks, refueling |
| Fan noise is heard, no cold | Evaporator freezing, channels blocked | Defrost 24 hours, check heating element |
| The temperature fluctuates, sometimes cold, sometimes warm | The temperature sensor is faulty | Replacing the sensor |
Mechanical damage and seals
Do not discount simple mechanical reasons. If sealing rubber the door of the refrigerator compartment is worn out, dirty or damaged, warm air from the kitchen constantly enters the chamber. The cooling system simply cannot cope with the compensation of heat gain, especially in the summer.
Check the door for a tight fit. To do this, you can clamp a sheet of paper between the door and the body: if it comes out without force, it means the seal is broken. The reason may also be that the door is skewed due to improper installation or loosening of the hinges, which often happens after transportation or overloading of the shelves.
Another factor is the location of the refrigerator. If it is placed close to a wall or in a niche with no gaps for ventilation, the compressor will overheat and reduce efficiency. Make sure that the gap at the back is at least 5-10 cm, and that there is space on the sides for air circulation.
☑️ Diagnosis of the seal
Failures in the operation of the electronic control module
Modern refrigerators Samsung are controlled by complex electronics. Main control module (Main PCB) collects information from all sensors and makes a decision about turning on the compressor, fan and heating element. If the fan control triac or compressor relay burns out on the board, or the processor “glitches,” the system stops responding adequately to temperature changes.
Often the cause of failures is power surges in the network. Even if the board is externally intact, microscopic solder cracks or damaged traces can lead to intermittent failures. In such cases, the refrigerator may behave chaotically: it may freeze, then turn off, or display errors on the display (if there is one).
Diagnostics of the module requires special knowledge and equipment. If all mechanical parts (sensors, heating elements, fan) are in good working order, and the cold does not occur, the probability of a control board malfunction tends to 90%.
⚠️ Attention: Before replacing or reconnecting the wires on the control module, be sure to take a photo of the original connection. An error in one contact can lead to a short circuit and final failure of the board.
Frequently asked questions (FAQ)
How long does it take to defrost a Samsung refrigerator if it is frozen?
For complete defrosting of the system No Frost and evaporation of all moisture from hard-to-reach channels, a minimum of 24 hours is required. Defrosting for 2-3 hours is often insufficient, since the ice in the depths of the air ducts does not have time to melt, and after turning on the problem returns after a couple of days.
Why is the "Cooling" indicator flashing?
A flashing indicator on the control panel Samsung usually indicates that the temperature in the chamber is higher than the set one, or a system malfunction has occurred. If the blinking continues for more than a day after loading food, this may indicate a sensor malfunction or a freon leak.
Is it possible to operate the refrigerator if the top does not freeze, but the bottom does?
For a short period of time - yes, but you cannot store perishable food in the upper chamber. Long-term operation in this mode is harmful for the compressor, which will wear out, trying to compensate for the lack of cold. It is better to eliminate the cause of the breakdown.
How to reset the error on a Samsung refrigerator?
A full reset often helps: unplug the refrigerator for 15-20 minutes. This will allow the electronics to reboot. If the error is caused by a temporary power surge, it may disappear. If the reason is hardware, the error will return after a cycle of operation.
Does the amount of food affect the cooling of the upper chamber?
Yes, it does. If you load the refrigerator to capacity with warm food, the system will take time (up to 12 hours) to reach the operating mode. Also, you should not block the air ducts on the back wall with food - this blocks air circulation, and the cold does not reach the front shelves.