The situation when freezer compartment continues to freeze food properly, but the main compartment suddenly becomes warm, is one of the most common and insidious problems in household appliances. Users often fall into a stupor, believing that if there is “cold”, then the equipment is working properly, but this is a classic symptom of a refrigerant circulation problem or a failure in the control system. In modern models, especially with the system No Frost, the cold is generated precisely in the evaporator, which is most often located in the freezer compartment, and then distributed among the chambers.
If you are faced with the fact that compressor hums without stopping, but there is cold in the upper there is no separation, indicating that the system is trying to compensate for a leak or blocked air flow. Ignoring this problem for several days can lead to complete spoilage of food and failure of expensive components such as the motor or control board. It is important to promptly carry out initial diagnostics to understand whether you need to call a technician or whether the problem can be solved yourself.
⚠️ Attention: Long-term operation of the compressor in non-stop mode with damaged thermal insulation or freon leakage can lead to overheating of the motor windings and its combustion, which is expensive repair.
The principle of operation of the cooling system and the distribution of cold
To understand why a temperature imbalance occurs, it is necessary to briefly consider the device refrigeration circuit. Most modern units use a single compressor that pumps refrigerant through a condenser and capillary tube. The main heat exchange occurs in the evaporator, which is often structurally located in the freezer area. It is there that the air is cooled to extremely low temperatures.
Then the ventilation system comes into play. A special fan (fan motor) forces cold air from the freezer into the refrigerator compartment through special channels. If this mechanism works correctly, the temperature is equalized according to the settings. However, if the air flow is (clogged) or if the refrigerant does not have time to go through the full cooling cycle due to a lack of freon, there is still cold in the freezer, but it simply does not reach the upper compartment in the required volume.
There is also a difference between the systems Direct Cool (drip) and No Frost. In drip models, the evaporator is often built into the back wall of the main compartment, and there a “freezing or not freezing” problem may indicate local freezing or thermostat failure. In systems No Frost the reason almost always lies in a violation of air circulation or freezing of the evaporator in a hidden area.
Mechanical obstacles: icing and clogged channels
One of the most common reasons why refrigerator stops cooling the upper chamber when the freezer is running is simple icing of the air channels. In systems No Frost moisture from food and air condenses on the evaporator and must be thawed regularly. If the defrosting system fails, the ice coat grows and blocks the channels through which cold air should flow into the main compartment.
As a result, the fan circulates air inside the freezer, creating severe frost there, but only warm air from the kitchen or residual cold enters the refrigerator compartment. This often happens when there is a malfunction Defrost heating element, timer or defrost sensor. Ice can completely block the outlet, and no temperature settings will help until the ice blockage is removed.
It is also worth checking the tightness of the products against the back wall. If you've recently loaded a lot of food and pushed the bags close to the vents, you may have mechanically blocked the flow. This is not a breakdown, but the effect will be identical - warm at the top, ice at the bottom.
☑️ Initial check of the defrosting system
If after complete defrosting for 24 hours (this is how long it can take for ice to melt in hidden channels), the problem recurs after 1-2 weeks, it means the problem is faulty one of the elements of the automatic defrosting system. In this case, it is necessary to replace a burnt heating element or a defective sensor.
Problems with the refrigerant: freon leak
The second most common reason is refrigerant leak. Freon circulates in a closed circuit: first it passes through the condenser (grid at the back), then through the capillary tube and enters the evaporator. If a microcrack appears in the circuit (often in the foamed part of the body or at soldering points), the pressure drops.
Why then does the freezer continue to freeze? Because the evaporator often starts in the freezer. The refrigerant, even in a reduced amount, manages to boil and give off cold at the beginning of its journey (in the freezer), but it is not enough to reach the end of the circuit (refrigerator compartment), or it arrives there already in a gaseous state, without having any cooling capacity. This phenomenon is called “under-boiling” or a shift in temperature.
⚠️ Attention: Refilling the refrigerator yourself without finding and eliminating the leak is a temporary measure that will lead to repeated breakdowns in a few weeks or months. Freon is not consumed during operation!
Symptoms of a leak can also be:
- 🧊 The side walls of the refrigerator are too hot (the compressor is wearing out).
- 🔇 Periodic turning on and off of the compressor at short intervals.
- 🌡️ Lack of cold in both chambers when the problem is ignored for a long time.
- 🔊 Change in the sound of the motor (louder humming or clicking).
For accurate diagnosis of leaks, technicians use leak detectors and pressure gauge stations. Visually finding the location of the leak, especially if it occurred in the foamed layer (“sandwich” of the case), is almost impossible without special equipment.
Where does the leak most often occur?
Most often, microcracks form in the heating circuit of the door perimeter (so that the door does not freeze) or in the places where the capacitor is factory soldered. Over time, metal corrosion makes the tubes thin, and freon pressure breaks through the wall.
Faults in the compressor and start relay
Compressor are the heart of the refrigerator. If it does not work correctly, pressure is not created in the system. There are times when the compressor starts, but does not develop enough power to pump freon throughout the entire circuit. This may be due to the exhaustion of the life of the valves inside the motor.
In such a situation, there is pressure at the outlet, and at the first heat exchange point (freezer) the cold is felt, but the circulation is disrupted. Also a common problem is malfunction starting relay. If the relay is burnt out or stuck, the compressor may hum but not start, or start jerkily. In some cases, the relay allows you to start the motor, but it operates in abnormal mode.
Diagnostics of the compressor requires measuring the current and discharge pressure. If the current consumption is significantly lower than the nominal one, and there is no pressure, this is a sign of loss of compressor performance (valve breakdown). If the current is high and the motor hums and clicks, the mechanical part may be stuck or the relay is faulty.
| Symptom | Probable cause | Nature of motor operation |
|---|---|---|
| The freezer is freezing, the top warm | Freon leak / Clogged | Works continuously or turns on frequently |
| Humming and clicking, no cold | Faulty start relay | Tries start, then a click and silence |
| Warm everywhere, the motor is cold | Open circuit / Burnt out motor | Does not turn on at all |
| Intense cold in both compartments | Malfunction thermostat | Works without stopping |
Electronics failures: sensors and control board
In modern electronically controlled refrigerators (where the temperature is set in degrees on the display), the climate inside the chambers is responsible thermal sensors. There are usually two of them: one in the refrigerator compartment, the other in the freezer (or evaporator area). If the sensor of the fridge compartment produces incorrect data (for example, it “shows” -5°C, although it is +15°C), the “brain” of the refrigerator will not give a command to cool, believing that the norm has been reached.
In this case, the freezer can be cooled according to the residual principle or due to the operation of a separate circuit (in two-compressor models). In single-compressor models with electronics, sensor failure often results in the fan stopping turning on to draw air from the freezer.
It is also worth mentioning clogged capillary tube. This is a technical malfunction in which a plug from oil or moisture breakdown products forms in a narrow section of the pipeline. The symptoms are similar to a leak: the freezer is stone cold, but the refrigerator is warm. The difference is that when clogged, the compressor works very hard and gets very hot, and the tube before entering the evaporator can be covered with frost or, conversely, be dry and warm where it should be cold.
Specifics of two-compressor models
If you have a refrigerator with two compressors (a separate motor for the freezer and a separate one for the refrigerator compartment), then the situation “the freezer freezes, but the refrigerator does not” simplifies the diagnosis. This means that the refrigeration chamber circuit is isolated and the problem is localized there.
In such cases, the options are as follows:
- ❄️ The refrigeration chamber compressor is faulty (does not start or does not pump).
- 📉 Freon leakage is in the refrigeration compartment circuit.
- 🔌 There is a problem with the control board that does not send a signal to the second motor.
- 🌡️ The refrigerator thermostat is faulty (does not close the circuit).
Two-compressor systems are considered more reliable in terms of temperature conditions, since shutting down one circuit does not affect the other, but repairing them is often more expensive due to the presence of two motors and a larger number of filling ports.
⚠️ Attention: In two-compressor models, the operating noise may be asynchronous. Do not be alarmed if the motors turn on one by one - this is a normal operating mode to save energy.
Human factor and settings
Before calling a technician, it is worth eliminating trivial operating errors. Sometimes users accidentally touch the temperature control or activate special modes. For example, the Super Freeze (Super Freeze) mode in some models can prioritize cooling of the freezer compartment, temporarily reducing the activity of the refrigerator compartment circuit for maximum freezing of food.
It is also worth checking whether the refrigerator compartment door is not open tightly. If the seal is worn out or the door is warped, warm air constantly flows inside. The sensor will register heat and the compressor will run continuously, but due to a leak, the cold will evaporate faster than it accumulates, creating the illusion of a breakdown.
Check the settings:
- Make sure that the "Holiday" (Eco) mode is not turned on, which can keep the temperature in the refrigerator compartment elevated to save money energy.
- Check the position of the air distribution damper (if there is a mechanical regulator).
- Make sure that the products are not lying on the shelf directly at the outlet of cold air.
Why did the refrigerator start working after defrosting, but after a week it stopped again?
This is a sure sign of a malfunction of the defrosting system (heating element, sensor or timer). Ice has again accumulated in the evaporator and blocked the channels. The burnt element of the defrost system needs to be replaced.
Is it possible to continue to use the refrigerator if the freezer is freezing and it is warm at the top?
For a short time - yes, the food in the freezer will be preserved. However, food in the refrigerator compartment will spoil. In addition, long-term operation of the compressor without rest cycles (due to the fact that it cannot gain temperature) can lead to its overheating and combustion.
How much does repair cost if the compressor burns out?
Replacing a compressor is a complex and expensive repair, including the cost of a new motor, starting relay, filter drier and repair work vacuuming and refilling with freon. Often the cost of such repairs is 50-70% of the price of a new refrigerator, so it is often more advisable to buy new equipment.
How to understand that a freon leak has occurred in the foamed part?
Only a technician with a leak detector can determine this for sure. An indirect sign is if, when the refrigerator is operating, there is no characteristic heating on the side walls (where the circuit is foamed), or the heating is uneven, although the compressor is hot. This is also indicated by the lack of effect after regular refilling without searching for a leak.
What to do if the refrigerator makes a strange sound (gurgling, hissing)?
Gurgling and hissing are normal sounds of freon and oil moving through the pipes, especially immediately after the compressor is turned off. However, if the sounds become louder, a whistle or knocking appears, this may indicate a circulation problem or problems with the compressor.