The situation when freezer compartment continues to work properly freezing food, and the main section of the refrigerator becomes warm, often takes you by surprise. This is a classic symptom of poor refrigerant circulation or a malfunction in the temperature control system. Instead of panicking and calling a technician from the first minute, it is worth carrying out an initial diagnosis, since in 30% of cases the problem is solved without expensive repairs.
The reason lies in the physics of the operation of single-compressor i double-compressor systems. In most modern models, cold is supplied to both chambers by one unit, but it is distributed unevenly in case of breakdowns. If you notice that temperature conditions the upper compartment is broken and there is ice below, this is a signal that the freon either does not reach the evaporator of the refrigerator compartment, or the system “thinks” that the cold has already been reached.
It is important to understand that ignoring the problem can lead to food damage and more complex compressor repairs. In this article, we will look at the mechanical and electrical reasons why refrigerator stopped cooling, and how to determine whether you need replacement parts or simple defrosting.
Principle of operation and distribution of cold
To understand the essence of the breakdown, you need to know how the cold gets into different zones. In systems No Frost a fan drives cold air from the freezer into the upper chamber through special channels. If this flow is blocked by ice or blockage, the freezer will work for wear, creating ice, and heat simply will not flow into the refrigerator.
In drip systems (crying evaporator), the tubes are located on the back wall or hidden behind the panel. Here refrigerant passes first through the freezer, giving up some of the cold there, and then enters the main compartment. If there is little freon in the system (leakage), it is only enough for the first stage of the cycle - freezing, and it no longer reaches the top in the required state.
There is also the concept of a “bypass valve” in some models, which regulates the flow. Its malfunction leads to the fact that all the cold goes into one zone. A critical sign of a leak is that the compressor runs continuously without turning off, trying to gain temperature, but there is no success.
⚠️ Attention: If you hear gurgling or hissing inside the housing after stopping the motor, this is a sure sign of movement of the gas-liquid mixture, which often indicates a low level of freon or blockage.
Different brands use different schemes. For example, in Indesit and Ariston there is often a factory defect in the sealing of the capillary tube, and Liebherr it is famous for its reliable but complex damper control electronics. Understanding the structure of your model (Atlant, Bosch, LG) will help you narrow down your search.
Mechanical reasons: blockages and ice jams
One of the most common reasons why freezer works, but the refrigerator is warm, is the formation of ice plugs in the air supply channels. This is especially true for the system No Frost. Ice blocks the path of warm air masses from the main chamber to the evaporator.
A technical clogging capillary tube is also possible. A microscopic plug of oil or moisture oxidation products may form inside the freon circulation system. This breaks the pressure: before the blockage it is high (the freezer is freezing), and after it is low (the refrigerator is warm).
How to distinguish an ice plug from a blockage?
An ice blockage is often formed due to a loosely closed door or a malfunction of the defrost heating element. A clogged capillary is an internal system problem that often requires purging with nitrogen and replacing the filter drier.
To diagnose mechanical problems, you can perform the following steps:
- ❄️ Completely defrost the refrigerator within 24 hours (unplug with doors open).
- 🔊 Listen to the sound of the operating compressor: is it a steady hum or an intermittent one?
- 🌡️ Check the temperature of the back wall inside the refrigerator compartment (it should be evenly cold or covered with frost).
If after a day of defrosting the refrigerator turned on and began to freeze normally in both chambers, but after 1-2 weeks later the situation repeated itself, which means the problem is in the defrost system (burnt out Heating element, timer or sensor).
Problems with refrigerant: freon leaks
Leak freon — the second most popular cause of temperature imbalance. Freon is a working fluid that transfers heat. When its amount in the circuit decreases due to a microcrack in the evaporator or corrosion of the tubes, the performance of the system drops.
Why does the freezer still freeze when there is a leak? Because the compressor continues to pump what is left. The areas closest to the compressor outlet and the entrance to the freezer evaporator freeze first. The refrigerant reaches the main compartment of the refrigerator already warm or in the form of steam, without having time to pick up the heat.
☑️ Signs of a freon leak
It is difficult to find the leak on your own, as it is often hidden in foam layer of the body or in sealed joints. Visually, you can notice oily stains on the floor under the refrigerator or on the pipes at the back, if access is open.
Freon charging is a procedure that requires special equipment (vacuum pump, pressure gauge station). You can’t just “top up” gas, you need to find the leak, seal it, replace filter-drier and only then refill the system.
Faults of the thermostat and sensors
Electronics controls the "brains" refrigerator. If thermostat (in mechanical models) or temperature sensor (in electronic) are out of order, they may transmit incorrect signals to the control module. For example, the sensor “thinks” that the refrigerator is already -5°C, and turns off the cold supply, although it is +15°C.
In models with electronic control (Samsung, LG, Beko), the air valve often fails sensor located at the top of the refrigerator compartment. It may oxidize or simply lose calibration. In this case, normal values may appear on the display, or, conversely, an error may flash.
Checking a mechanical-type thermostat is simple: you need to remove the regulator handle, unscrew the screws and carefully remove the unit itself. By ringing the contacts with a tester at different temperatures, you can understand whether the circuit opens. If the contacts are “stuck” in the open state, no cold will be produced.
⚠️ Attention: When replacing sensors, be sure to use models with identical resistance. Installing an unsuitable sensor will lead to incorrect operation of the compressor and possible freezing of the products.
A frequent problem is also the breakdown of the control module, which simply “does not see” the sensors or does not supply voltage to the solenoids that open the supply of freon to different circuits.
Failures in the operation of the compressor and start relay
Although less common, it happens that it itself compressor loses its performance. It may hum, creating the appearance of work, but not create the necessary pressure in the system. This is called "loss of productivity". In this case, the freezer is barely freezing, and the refrigerator is completely defrosted.
It is also worth paying attention to starting relay. If it is faulty, the compressor may try to start, click and switch off after a few seconds (thermal protection). Or work only on one winding, without developing full power.
Compressor diagnostics include:
- 🔌 Checking the current strength of the windings (a multimeter is needed).
- 🔨 Listening to startup sounds (there should be a confident hum, not a crackling sound).
- 🌡️ Measuring the temperature of the motor housing (severe overheating indicates an interturn short circuit).
If the compressor is hot, but does not start or works at half capacity, most likely In all, it will need to be replaced. This is an expensive repair that often requires resoldering the entire system.
Diagnostic table: symptoms and solutions
For convenience, we will systematize the main symptoms of a malfunction in a table. This will help you quickly navigate the nature of the breakdown.
| Symptom | Probable cause | Difficulty of repair | Necessary actions |
|---|---|---|---|
| The freezer is freezing, in The refrigerator is warm, the compressor is silent | The thermostat or sensor is faulty | Low | Replacing the sensor/thermostat |
| The compressor hums incessantly, there is no cold | Freon leak or capillary blockage | High | Looking for leaks, vacuuming, refilling |
| Ice in the freezer, warm in the refrigerator, works after defrosting | System failure defrost (No Frost) | Average | Checking the heating element, timer, fuse |
| The compressor clicks and turns off | Start relay or compressor windings | Medium/High | Replacing a relay or compressor |
Algorithm of actions when a problem is detected
If you find that refrigerator stopped cooling, do not rush to buy a new one. Follow the plan. First, rule out simple reasons: check whether the door is tightly closed, whether the ventilation duct is not clogged with food, whether the temperature is set correctly.
Then carry out a complete defrost. This is a free diagnostic method that eliminates ice jams. If after turning on the network after 2-3 hours (the time of the first cycle) the situation has not changed, then the problem is technical.
When calling a specialist, be sure to describe the symptoms: is the compressor working, is there ice in the freezer, how long ago has the problem appeared. This will help the technician take the necessary equipment with him.
⚠️ Attention: Do not try to open a sealed circuit yourself or change the compressor without soldering and vacuuming skills. This can lead to complete failure of the equipment and is dangerous to health due to the possible ignition of some types of freon.
Frequently asked questions (FAQ)
Why did the refrigerator work after defrosting, but after a week it stopped again?
This is a classic sign of a malfunction of the defrost system in No Frost models. Most likely, the defrost heating element, timer or defrost sensor has burned out. Ice again accumulates on the evaporator and blocks the air supply channels.
Is it possible to operate the refrigerator if the freezer is freezing, but the upper compartment is not?
For a short time - yes, the food in the freezer will not spoil. However, long-term operation in this mode (especially if the compressor does not turn off) will lead to overheating and combustion of the motor-compressor, which is much more expensive to repair.
How much does the repair cost if refilling with freon is needed?
The cost consists of the work of the technician, the cost of freon, oil and filter-drier. The price may vary depending on the region and model of the refrigerator, but usually this is an average cost repair.
Why is the back wall of the refrigerator covered with ice, but the inside is warm?
This indicates that the evaporator is working, but the cold does not circulate through the chamber. Either the fan is faulty (in No Frost), or the air supply channels are clogged with food or ice.