The situation when the food in the freezer remains hard, but the main compartment is warm, can take any owner of household appliances by surprise. This is not just an inconvenience, it is a signal that cooling system it has failed and the refrigerant has stopped circulating in full. Often, users ignore the first signs, trying to simply reduce the temperature on the thermostat, but the problem lies deeper.
Before calling a technician or disassembling the unit, it is necessary to conduct an initial diagnosis. It is important to understand that modern models with a No Frost system are more complex than old two-chamber refrigerators with a drip system. In them, the cold from one evaporator is distributed across both chambers, so a breakdown of one unit can lead to the described temperature imbalance.
In this article we will analyze in detail the mechanical and electrical causes of the malfunction. You will learn how to check compressorwhy it may fail thermostat and what to do if the capillary tube is clogged. Correct diagnostics at the initial stage will help save money and time.
⚠️ Attention: Before starting any work related to disassembling the case or checking electrical circuits, be sure to disconnect the refrigerator from the power supply. Working with electrical appliances under voltage is dangerous to life.
Checking the tightness and condition of the seals
The most commonplace, but most common reason is a violation of the seal of the main compartment door. If the rubber seal does not fit tightly, warm air constantly enters the chamber. The compressor tries to compensate for the heat by working non-stop, but the system’s power may not be enough to cool a large volume, while the cold remains in a small freezer.
Carefully inspect the rubber band around the entire perimeter. There should be no cracks, creases or adhering dirt that would interfere with a tight fit. Often the problem lies in the deformation of the magnetic tape inside the seal. Check whether the door itself is level and not sagging.
To quickly check the tightness, you can use a simple test with a sheet of paper. Clamp the sheet between the door and the body at different points and try to pull it out. If the paper is pulled out without resistance, then the seal is broken in that area.
- 🔍 Inspect the seal for visible damage and tears.
- 🧼 Wipe the elastic band and the mating part of the body with a damp cloth.
- 📏 Check the tight fit of the door with using sheet dough.
- 🔧 Make sure that the door hinges are not skewed and allow the door to close tightly.
Malfunctions of the defrost system in No Frost refrigerators
If you have a model with the system No Frostthen the most likely reason is a failure in the system evaporator defrost. In such refrigerators, cold air is forced by a fan from the freezer into the refrigerator. If the evaporator in the freezer becomes overgrown with a “fur coat” due to unthawed ice, the air channels are blocked.
As a result, the fan circulates air, but it cannot pass through the ice shell into the main compartment. At the same time, the freezer continues to freeze, since the evaporator is located there, and it is hot in the refrigerator compartment. The defrost process is controlled by defrost heating element, timer (or an electronic module) and defrost thermostat.
Most often the heating element burns out or the sensor fails and does not give a command to turn on the heating. Ice accumulates cyclically until it completely blocks the circulation channels. This can be seen visually if you remove the back panel in the freezer - a large lump of ice will be visible there.
How to defrost a refrigerator to check?
Unplug the appliance for 12-24 hours with the doors open. If, after complete defrosting and turning on, the refrigerator started working normally, but after 1-2 weeks the problem recurred, the diagnosis of “malfunction of the defrost system” is confirmed.
It is necessary to check the integrity of the heating element with a multimeter. If the resistance of the heating element is infinitely high, it means that the coil has burned out and requires replacement. It is also worth checking the defrost thermostat, which should open the circuit when a certain temperature is reached.
Problems with the compressor and start relay
The compressor is the “heart” of the refrigerator. If it does not work at full capacity or does not start on the second circuit (in two-compressor models), the cold in the main compartment disappears. However, if the freezer is working, then the compressor itself is most likely alive, but there may be problems with its efficiency or control.
In older models with one compressor and one circuit, this situation (the freezer freezes, the refrigerator does not) often indicates a compressor or a refrigerant leak. The engine hums, but there is no required pressure in the system. In two-compressor models, everything is simpler: the second compressor, which is responsible only for the refrigeration chamber, could burn out. loss of performance compressor or refrigerant leak. The engine hums, but there is no required pressure in the system. In two-compressor models, everything is simpler: the second compressor, which is responsible only for the refrigeration chamber, could burn out.
Particular attention should be paid to the starting relay. This is a small box on the side of the compressor. If it is faulty, the compressor may hum, click, but not start, or start and immediately stall. Check the relay for contact deposits or mechanical damage.
| Symptom | Possible cause | Action |
|---|---|---|
| The compressor hums, but does not start | The starting relay is faulty or the compressor is jammed | Replace the relay, call a technician |
| Compressor is hot, cold is weak | Freon leak or system clogged | Looking for leaks, refilling |
| The compressor does not turn on at all | The thermostat or control module is faulty | Electrical diagnostics |
Clogged capillary tube or freon leak
One of the most difficult problems to fix on your own is impaired refrigerant circulation. If there is a formation in the system (often in the area of the capillary tube or filter drier), freon cannot circulate freely throughout the circuit. microscopic blockage (often in the area of the capillary tube or filter drier), freon cannot circulate freely throughout the circuit.
In this case, part of the circuit (usually in the freezer) will be cold, and the rest (in the refrigerator) will be cold. warm. You can often hear gurgling or hissing noises inside the cabinet. Another option is freon leak. If there is not enough gas in the system, it is only enough for the beginning of the cooling cycle, that is, for the freezer.
It is difficult to determine a leak visually, since freon is colorless and odorless. However, if you notice oily spots on the rear grille or where the tubes connect to the compressor, this is a sure sign of depressurization. It is impossible to fix this problem on your own.
⚠️ Attention: Filling the refrigerator with freon and searching for leaks requires special equipment (vacuum pump, pressure gauge station, leak detector). Do not try to simply “add gas” without eliminating the cause of the leak - this will lead to compressor failure.
To confirm the diagnosis, technicians often cut off the capillary tube and look at the gas pressure. If the gas comes out with a hissing sound, there is no leak and the problem is a clog or compressor. If the gas does not come out, look for where the circuit is damaged.
Malfunction of the thermostat or electronic module
The thermostat (or temperature sensor in electronic models) regulates the operation of the compressor. It “tells” the system when to turn on and when to turn off. If the sensor in the refrigerator compartment “lies” and shows that it is already cold there, the compressor simply will not turn on to cool this compartment.
In mechanical models, the thermostat has a long capillary tube that is attached to the evaporator. If this tube is loose or damaged, the thermostat will not sense the actual temperature. In electronic models with a display, the NTC sensor.
You can check a mechanical thermostat by closing its contacts directly. If after this the refrigerator starts working normally (and both compartments freeze), then the problem is in the regulator. However, remember that in this mode the refrigerator will not turn off on its own.
☑️ Thermostat diagnostics
Failure of the airflow control damper
In modern two-chamber refrigerators, especially with the system Total No Frost, a special damper is often used to regulate the flow of cold air from the freezer to the refrigerator compartment. This is a mechanical or electric damper that opens based on a sensor signal.
If the damper is stuck in the closed position, cold air physically cannot enter the upper chamber. The freezer operates normally, even with excessive capacity. This malfunction is typical for brands Liebherr, Bosch, LG.
To check the damper, you need to get to the air duct (usually on the back wall of the refrigerator compartment or at the top). Manually try to open and close the damper. If it moves slowly or does not respond to commands (in electric models), it must be replaced or lubricated (if the design allows).
When you need to call a professional technician
Despite the desire to save money, there are situations when independent repairs can lead to final breakdown of the unit. If diagnostics indicate problems with the tightness of the circuit, freon leakage or replacement of the compressor itself, it is better to contact specialists.
Also, the help of a specialist is needed if replacement is required evaporatorsealed into the wall of the refrigerator (the so-called “crying” evaporator). Opening the thermal insulation and sealing a new circuit is a complex technological operation that requires experience.
Do not forget that after repairs associated with opening the cooling system, professional vacuumization and charging with the exact amount of refrigerant is required. Violation of the technology will lead to rapid breakdown of expensive equipment.
Why does the refrigerator work silently, but does not freeze?
If the compressor does not make sounds or vibrate, but the light inside is on, it means that the power-on signal does not come to it. Most likely, the thermostat, start relay or electronic control module is faulty. The compressor simply “sleeps.”
Is it possible to operate the refrigerator if the freezer is working but the refrigerator is not?
For a short time - it is possible if you temporarily transfer the food to the freezer. However, prolonged operation in this mode is dangerous for the compressor, which can work non-stop, trying to gain temperature, which will lead to its overheating and burning of the windings.
How often do you need to defrost a No Frost refrigerator?
The No Frost system does not require manual defrosting to remove ice, as this happens automatically. However, it is recommended to turn off the refrigerator once every 6-12 months for hygienic washing and checking the condition of the seals and drainage holes.