The situation when you open the refrigerator door in the hope of getting a chilled drink, and there is room temperature, while the freezer section is working properly and even “overgrown” with excess frost, is a classic sign of a serious technical problem. Many users mistakenly believe that if the compressor is humming and the freezer is functioning, then the problem is not serious and will solve itself after defrosting. However, such a temperature asymmetry is direct signal a violation of the refrigerant circulation or failures in the control system.
In normal operation of a two-chamber unit, the cold is distributed evenly or supplied according to a certain algorithm, ensuring the safety of products in both compartments. When one of the circuits ceases to perform its function, this indicates that the physics of the heat transfer process is broken. Ignoring the first symptoms, such as insufficient cooling upper compartment, can lead to damage to a large number of products and higher costs for subsequent repairs.
In this article we will analyze in detail the mechanical and electrical causes of such a problem, explain how to carry out the initial diagnosis on your own and when it is necessary to call masters Understanding the principles of operation of the freon system will help you avoid unnecessary expenses and quickly localize the source of the disaster.
The principle of operation of the No Frost system and static refrigerators
To understand why a temperature imbalance occurred, you need to briefly brush up on the theory of operation refrigeration equipment. In modern models, regardless of whether technology is used No Frost or static cooling (“crying wall”), the cold is generated in the evaporator, which is most often hidden from the user’s eyes. In units with the No Frost system, the fan drives air through the evaporator and distributes it among the chambers through special air ducts.
If we are talking about static models, then the evaporator is located in the wall of the refrigerator compartment, and the freezer has its own separate circuit or is a continuation of the main one. In both cases, the key element is refrigerant circulation the correct operation of the thermoregulatory elements. Violation at any stage - from gas compression to the distribution of air flows - leads to the described problem.
⚠️ Attempts to independently open a sealed circuit or add freon without evacuation of the system will lead to complete breakdown of the compressor and moisture getting inside, which will make further repairs economical inappropriate.
It is important to distinguish between the design features of your model. In some cases, the same evaporator is responsible for cooling the refrigerator compartment as the freezer; air is simply supplied through a damper. In others, these are two independent circuits. The list of probable faults depends on this. For example, in models Indesit or Atlant with one compressor the problem often lies in a leak, and in two-compressor Liebherr or Bosch the failure of one of the units.
Freon leakage: the most common reason
The most likely reason why the freezer continues to freeze and the refrigerator compartment is warm is partial refrigerant leak. Freon is a working fluid that circulates in a closed loop, taking heat from the chambers and releasing it to the environment through a condenser (grid at the back). When a microcrack appears in the system, the amount of gas decreases.
Why is the freezer still working? The remaining freon is only enough to cool the first section of the circuit - the evaporator of the freezer. The gas simply does not reach the refrigerator compartment or reaches it already in a warm state. You may notice that over time, the freezer will begin to cope worse, and the compressor will work almost non-stop, trying to gain temperature.
- 🔍 Visual inspection: carefully inspect the back wall and the joints of the tubes for oily stains (freon carries oil with it).
- ❄️ Ice behavior: pay attention to the character freezing - if ice forms only at the entrance to the evaporator, this is a sure sign of a lack of gas.
- 🔊 Sound of operation: listen to see if the compressor begins to hum louder or work non-stop.
Only a specialist can accurately diagnose a leak using a leak detector and a pressure gauge station. You can only assume this malfunction on your own if you heard a hissing sound when moving the refrigerator or saw mechanical damage to the case. In 80% of cases, it is necessary to find the leak, seal it, evacuate the system and charge a new portion of refrigerant.
Clogged capillary pipeline
The second most popular “culprit” for the lack of cold in the main chamber when the freezer is running is clogged capillary tube. This thin pipeline serves as a throttle separating the high and low pressure zones in the system. During operation, paraffin deposits may form in the oil circulating along with freon or microscopic particles of debris may enter.
When the lumen of the tube narrows or is completely blocked, the circulation of the refrigerant is disrupted. The compressor tries to push gas, but encounters resistance. As a result, the pressure drops and freon cannot effectively cool the entire volume of the evaporator. Often in such cases, you can hear how the compressor turns on, works for a while, and then clicks and turns off - the overload protection is triggered. thermal relay overload protection.
Signs of a blockage are often confused with a leak, but there is a nuance: if the condenser (grid at the back) is clogged, it can be cold or warm only partially, as opposed to a leak where it is usually completely cold. Another characteristic sign is that after a long defrosting (for a day), the refrigerator may begin to work normally, but after a few days the problem returns.
Removing the blockage requires a professional interventions. The technician may try to “push through” the blockage with high-pressure nitrogen or replace a section of the capillary tube. This is a labor-intensive process that requires special equipment and soldering skills.
Malfunctions of the defrost system (Defrost)
In refrigerators with a No Frost system, the proper operation of the defrost system is critical. If Defrost heating element, the defrost thermostat or timer (control module) fails, a huge lump of ice (“fur coat”) begins to grow on the evaporator. This ice blocks the ventilation holes through which cold air should enter the refrigerator compartment.
It can be very cold in the freezer, since it is located directly next to the frozen evaporator, but cold air simply does not enter the upper compartment. You may notice that the back wall in the refrigerator compartment is swollen or ice is visible on it, although it may not be visually visible in the chamber - it is hidden behind a plastic panel.
Diagnosis of this malfunction often requires partial disassembly of the inside of the freezer or removing the panel in the refrigerator compartment (depending on the model). It is necessary to check:
- 🔌 Integrity of the heating element: ring the heating element with a multimeter.
- 🌡️ Temperature sensors: check the resistance of the defrost sensors.
- ⏱️ Timer/Module: make sure that the command is on defrost is turned on.
What will happen if you ignore the problem with defrosting?
Constant operation of the compressor in an attempt to cool the chamber will lead to its overheating and eventual combustion of the windings. In addition, melting ice can overfill the drain pan and leak onto the floor, damaging the floor covering.
Problems with the compressor and its startup
Although less common, it happens that the problem lies in the very “heart” of the refrigerator - the compressor. If the unit two compressors (separately for the freezer and refrigerator), then the failure of one of them explains the situation 100%. In this case, the repair is relatively simple: the faulty unit is replaced.
In models with one compressor the situation is more complicated. If the compressor has “slowed down” and lost performance (compression), its power may only be enough to maintain a low temperature in the freezer, which is better insulated. You can check the compression by disconnecting the discharge tube: if gas comes out of it in a sluggish stream, the compressor requires replacement.
It is also worth paying attention to the start-up relay. If it is faulty, the compressor may hum but not start, or it may start for a few seconds and stall. In such cases, the freezer, having greater inertia, can keep the cold longer, creating the illusion of work.
| Symptom | Probable cause | Difficulty of repair | |
|---|---|---|---|
| The compressor works constantly, it is cold no | Freon leakage | High (needs a technician) | |
| The compressor hums and clicks, does not start | Clogged or broken compressor | High | High |
| The refrigerator turns on/off cyclically | Thermostat malfunction | Medium | |
| In the freezer ice, the refrigerator is warm, the fan does not make noise | Clogged air duct with ice (Defrost) | Average |
Diagnostics of the thermostat and damper
In some models, especially with the Full No Frost system, for the distribution of cold answers air damper. This is a mechanical or electrical valve that opens and closes at the command of the electronics, allowing cold air from the freezer into the refrigerator compartment. If the damper drive is stuck in the closed position or the damper motor is burnt out, the cold simply does not enter the upper chamber.
Also, the thermostat (thermostat) cannot be discounted. If it “lies” and sends the wrong signal that the chamber is already cold enough, the compressor will not turn on. Although in this case it usually does not get cold anywhere, there are cases of desynchronization of sensors in two-chamber systems.
⚠️ Attention: In modern electronically controlled refrigerators (where the temperature is set in degrees on the display) there are air sensors instead of a thermostat. Replacing them requires precise calibration and often reflashing the control module.
Checking the damper usually requires removing the inner lining of the refrigerator compartment. Make sure the shutter lever moves freely and is not blocked by ice or fallen food. In models Samsung and LG there is often a breakdown of the plastic gears of the damper mechanism.
☑️ Do-it-yourself primary diagnostics
Frequently asked questions (FAQ)
Is it possible to continue using the refrigerator if it does not freeze in the upper compartment?
For a short time - yes, if you transfer perishable foods to the freezer or use them immediately. However, prolonged operation in this mode is harmful to the compressor, which wears out trying to reach the set temperature. In addition, bacteria will quickly multiply in a warm chamber.
How much does repair cost if a compressor burns out?
Replacing a compressor is the most expensive type of repair, amounting to 60-70% of the cost of a new refrigerator. Often in such cases, it is more advisable to consider purchasing new equipment, especially if the refrigerator is more than 10 years old.
Why did the refrigerator work after defrosting, but after a week it stopped again?
This is a classic symptom of a clogged capillary tube or micro-leak. Defrosting temporarily eliminates the ice plug or allows freon residue to circulate, but the root cause (debris in the system or a hole) does not go away.
How to understand that the problem is in the control module?
If all mechanical parts (compressor, fan, heating element) are working, but the refrigerator does not respond to temperature switching or behaves chaotically, most likely In total, the electronic module is faulty. This requires diagnostics by a specialist with an oscilloscope.