The situation when the temperature rises sharply and food begins to deteriorate is familiar to many owners of household appliances. It is especially alarming when the lower part of the unit works properly, but the upper shelves remain warm. This is a classic symptom of poor refrigerant circulation or a malfunction in the temperature control system. Users often panic, believing that the equipment has completely failed, but in many cases the problem can be solved without calling a technician. refrigerator compartment The temperature rises sharply, and food begins to deteriorate, a situation familiar to many owners of household appliances. It is especially alarming when the lower part of the unit works properly, but the upper shelves remain warm. This is a classic symptom of poor refrigerant circulation or a malfunction in the temperature control system. Users often panic, believing that the equipment has completely failed, but in many cases the problem can be solved without calling a technician.
Modern two-chamber models, be it Indesit, Atlant or LG, are designed on the principle of forced or natural circulation cold air. If this process is disrupted, the cold stops flowing to the upper zone. Understanding the physical processes occurring inside the case will help you quickly localize the breakdown. In this article, we will analyze the main reasons why the refrigerator has stopped freezing in the upper compartment, and draw up an action plan for diagnosis.
It is important to immediately note that ignoring the problem can lead to failure of an expensive one. compressor. If the equipment works in increased mode, trying to compensate for the lack of cold, the load on the engine increases many times over. Therefore, at the first signs of a malfunction, it is necessary to carry out initial diagnostics in order to eliminate simple operating errors.
⚠️ Attention: If you hear an uncharacteristic hum, clicks or smell a burning smell, immediately disconnect the device from the power supply. Operation of faulty equipment can lead to a short circuit or fire.
Problems with the compressor and start relay
One of the most common reasons why the refrigerator does not freeze well above is incorrect operation compressor. In single-circuit systems, where one motor serves both chambers, it is he who is responsible for pumping freon throughout the entire system. If the compressor operates intermittently or does not gain the required power, there is not enough refrigerant pressure to reach the upper evaporator.
Often the culprit is the start relay. This small device responsible for starting the engine wears out over time. The contacts may burn out and the bimetallic strip may lose its properties. As a result, the compressor either does not start at all, or turns off after a few seconds of operation, without having time to create the necessary pressure in the system.
- 🔊 The compressor hums, but does not start, or starts with a loud click and immediately stalls.
- 🌡️ The rear engine grille remains cold, although the engine tries work.
- ⚡ Heating of the compressor itself occurs unevenly or it overheats in a matter of minutes.
Diagnosis of this malfunction requires caution. If you decide to test the start relay yourself, be sure to unplug the refrigerator. Remove the protective casing from the compressor and carefully remove the relay. Shake it: if you hear a ringing or knocking sound inside, it means the mechanical part is damaged and requires replacement. Also check the contacts for carbon deposits.
⚠️ Attention: Replacing the start relay requires precise selection of the model for a specific compressor. Using an unsuitable part can lead to burnout of the motor windings.
Leakage of refrigerant (freon)
If the refrigerator turns on, works, but the temperature in the upper chamber does not drop below +10...+15 degrees, there is a high probability freon leaks. In a working system, the refrigerant circulates in a closed circuit and is not consumed. However, over time, microcracks may form in the tubes due to corrosion or mechanical damage, through which the gas gradually evaporates.
When the amount of freon becomes critically small, there is not enough of it for the entire cooling circuit. Since the evaporator is usually located in the upper part or in the partition between the chambers, it is there that the cold stops flowing first. In this case, the compressor can work almost non-stop, trying to reach the set temperature, but to no avail.
It is rarely possible to detect a leak visually, since freon is colorless and odorless. However, there are indirect signs:
- ❄️ The evaporator (the back wall inside the chamber) is covered with ice unevenly or only in the lower part.
- 🔥 The condenser grille at the back remains barely warm or completely cold.
- 📉 The compressor operates in non-stop, but does not turn off for hours.
It is almost impossible to independently find the leak and refill the system without special equipment. A vacuum pump, pressure gauge station and scales are required for accurate gas dosing. Attempts to “refuel” the refrigerator without finding and fixing the hole will only give a temporary effect.
Is it possible to use freon from a can for cars?
No, under no circumstances. Refrigerants for household refrigerators (R134a, R600a) and automotive systems have different chemical compositions and pressures. Using the wrong gas will result in destruction of the compressor and an explosive situation, especially if R600a (isobutane) is used.
Clogged capillary tube
Another technical reason why the refrigerator does not cool top shelf is clogged capillary tube. This thin copper pipe serves as a choke, creating a pressure difference between the condenser and the evaporator. If moisture, oxidation products or paraffin deposits accumulate inside the tube, the circulation of freon is disrupted.
As a result of the blockage, freon cannot circulate freely throughout the system. The pressure in front of the capillary increases and behind it decreases. The evaporator either does not get cold at all, or is covered with frost only at the entrance. The compressor begins to work with increased load, which is often accompanied by a louder hum.
| Symptom | Probable cause | Solution method |
|---|---|---|
| The compressor is hot, its tubes are cold | Clogged in the capillary tube | Purge with nitrogen or replace the filter-drier |
| Ice only at the entrance to the evaporator | Partial blockage | Evacuation and refilling systems |
| The refrigerator is silent, but there is light | Complete blockage or failure of the electronics | Diagnostics of the thermostat and power circuit |
To eliminate this problem, the technician needs to depressurize the system, replace the filter-drier (which is often the cause of moisture accumulation) and purge the circuit with high pressure nitrogen. After this, evacuation is carried out and a new portion of refrigerant is charged.
Malfunction of the thermostat or sensor
In older models of refrigerators, mechanical ones are responsible for the temperature thermostat, and in modern ones - electronic sensors (thermistors). If this control fails, it may send an incorrect signal to the compressor. For example, “report” that it is already quite cold in the chamber, although in fact it is warm there.
In this case, the compressor simply does not turn on, and the temperature in the upper chamber is gradually compared to room temperature. You can check a mechanical thermostat by closing its contacts directly. If after this procedure the refrigerator starts working and starts freezing, it means that the regulator is faulty.
In electronic models Samsung, Bosch or Whirlpool diagnosis is more complicated. This often requires checking the resistance of the sensor with a multimeter at different temperatures. If the resistance values do not correspond to the rating table for a particular model, the sensor must be replaced.
⚠️ Attention: In models with the No Frost system, sensors can be located in different places: on the evaporator, in the air duct or in the chamber itself. An error in choosing the measuring location will lead to incorrect diagnosis.
No Frost system malfunction
If you have a refrigerator with the system No Frost (or Low Frost), and it stopped freezing from above, the problem may lie in freezing of the evaporator. In such units, the cold is produced in a hidden block and is pumped by a fan into the chamber through special channels. If the evaporator is covered with a thick coat of ice, air cannot circulate.
The cause of ice fouling is most often a malfunction of the defrost system. This could be a burnt heating element (heating element), a failed defrost relay or timer. Also, the defrost sensor often breaks down, which does not give the command to turn on the heater.
- 🌬️ The fan hums, but the air does not blow from the holes or blows barely.
- 💧 Water appears at the bottom of the refrigerator or under the vegetable drawers.
- 🧊 The back wall inside the freezer is covered with an uneven layer of ice or a snow coat.
To confirm the diagnosis, you often have to disassemble the back panel of the freezer. If ice is visible on the evaporator and the fan is clean, the defrost cycle is broken. A temporary solution may be to completely defrost the refrigerator within 24 hours, but to eliminate the cause, you will need to replace the defective part.
☑️ Checking the defrosting system
Deformation of the sealing rubber
Sometimes the reason for warm air from above is trivial - leakage doors. If sealing rubber the top door is worn out, dirty or deformed, warm air from the room constantly enters the chamber. The refrigerator tries to compensate for heat loss, but cannot cope, especially in the hot season.
You can check the tightness with a simple test with a sheet of paper. Clamp the sheet with the door in different places around the perimeter. If the paper comes out easily, without resistance, it means that the seal does not fit tightly in this place. Also carefully inspect the rubber for cracks, tears or sticky deposits.
If the rubber is simply dirty, just wash it with warm water and soapy water. If it has lost its elasticity, you can try to restore its shape by heating it with a hairdryer or boiling water (with caution). In case of serious damage, only complete replacement of the seal will help.
Frequently asked questions (FAQ)
Why is there cold in the freezer, but warm in the refrigerator compartment?
This indicates that the compressor is working, but there is no cold reaches the top compartment. Most likely, a freon leak has occurred, the capillary tube is clogged, or the fan is not working (in No Frost models). It is also possible that the air supply channels may freeze.
How long does it take to defrost the refrigerator when icing occurs?
To completely defrost the No Frost system or remove the ice plug in the channel, a minimum of 24 hours is required. The doors must be open. A shorter defrosting may not produce results, since the ice in hard-to-reach places will not have time to melt.
Is it possible to use a refrigerator if it does not freeze on top?
Short-term - yes, so that the food does not disappear. But long-term operation in this mode is dangerous for the compressor, which will wear out. In addition, bacteria will begin to multiply in a warm chamber. It is better to eliminate the malfunction.
Why, after defrosting, did the refrigerator stop freezing again after a week?
This is a classic sign of a malfunction of the defrosting system (heating element, timer, sensor) or the presence of a freon leak. Defrosting temporarily removes the ice jam, but does not eliminate the cause of its appearance. Diagnostics and replacement of defective components are required.