The situation when the refrigerator stops cooling food in the upper compartment often takes you by surprise. The lower chamber may be icy cold, and the upper chamber may be as warm as a room. This is a sure sign that the refrigerant circulation system is broken or the temperature sensor is faulty.
Before panicking and calling a technician, it is necessary to carry out initial diagnostics. Freon circulation disruption or failure of one of the electronic components may be the cause. In this article, we will look at the main breakdown scenarios and how to fix them.
Sometimes the problem lies in simple overheating or incorrect settings. However, if you hear that the engine is running non-stop, but there is no cold, the matter is more serious. Let's figure out why The refrigerator does not freeze the upper chamber and how to return it to functionality.
Primary diagnostics: checking simple reasons
The most common mistake is ignoring basic operating rules. If the unit is standing close to a wall or next to a radiator, heat exchange is disrupted. The compressor tries to compensate for the lack of cold by working hard, but the upper zone remains warm. Make sure that the gap between the back wall and the wall is at least 5-7 cm.
Check the thermostat settings. In some models with one compressor and No Frost system a failure in the electronics could disrupt the operating mode. Try defrosting the equipment completely (at least 24 hours) and turning it on again. If the problem does not go away, then the problem is in the hardware.
⚠️ Attention: Do not try to pick out the ice with a knife or other sharp objects. Damage to the evaporator will lead to freon leakage, which will require expensive repairs with sealing of pipes.
Pay attention to how tightly the doors are closed. If the sealing rubber is worn out or dirty, warm air constantly enters the chamber. The system does not have time to cool it, especially in the upper compartment, where cold air falls worst of all when the ventilation is faulty.
Refrigerant problems: freon leak or blockage
If you hear the quiet hum of the compressor, but it periodically turns off, and there is no cold anywhere (or it is weak), there is a high probability of a leak. Freon is the “blood” of the refrigerator. Without it, heat cannot be removed. In systems with one circuit, cooling often starts from the freezer, and only then does the cold go to the upper chamber.
Clogged capillary tube is another technical reason. Plugs from oil or moisture oxidation products may have formed in the circulation system. This blocks the flow of refrigerant. The pressure in the system increases, the compressor is overloaded, but the cooling capacity drops to zero.
It is difficult to visually determine a leak, but you can pay attention to swelling on the walls of the evaporator or a characteristic hissing sound when punctured (which you cannot do on your own). Also a sign is a hot condenser (grid at the back) with cold chambers.
Is it possible to fill a refrigerator with freon yourself?
Self-refueling is impossible without special equipment (vacuum pump, pressure gauge station, scales). In addition, you need to know the exact brand and dosage of the refrigerant indicated on the nameplate. An attempt to refuel “by eye” will lead to compressor failure.
To eliminate these problems, you need to call a specialist. He will perform a nitrogen pressure test, find the leak, replace the filter drier and refill the system. This is a standard procedure for refrigerator repair older than 7-10 years.
Faults of the compressor and start relay
The compressor is the heart of the refrigeration unit. If it does not start or operates intermittently, the upper chamber will not receive the necessary cooling. Often guilty starting relay. This is a small part that provides an impulse to start the engine. If the relay is “stuck” or burnt out, the compressor hums, clicks, but does not start.
You can check the relay visually (for the presence of carbon deposits) or by replacing it with a known good one. If the problem is in the motor itself (turn-to-turn short circuit of the windings), then the unit will get very hot and knock out the circuit breakers in the electrical panel.
In two-compressor models, the situation is simpler: one motor is responsible for the freezer, the second for the upper compartment. If the lower chamber freezes, but the upper one does not, it means that the upper compressor is faulty or does not receive a signal to turn on.
⚠️ Attention: Replacing the compressor requires soldering copper tubes and evacuating the system. This is a job for a professional with a burner and pump.
Sometimes the compressor is working, but cannot start due to low voltage in the network. If your light fluctuates frequently, install a voltage stabilizer. Operating the motor in such conditions reduces its service life by several times.
Failure of sensors and thermostat
Electronics controls the cooling process. If thermostat (in mechanical models) or temperature sensor (in electronic) transmits incorrect data, the compressor may simply not turn on. He “thinks” that it is already cold in the chamber, although in fact it is warm there.
In No Frost systems, a timer and a defrost sensor are responsible for defrosting the evaporator. If the sensor “lies” and shows that the evaporator is cold, although it is covered with ice, the system will not start the heater. The evaporator becomes overgrown with a “fur coat”, blocking the ventilation ducts. Cold stops flowing into the upper chamber.
Diagnostics of the sensors is carried out with a multimeter. The resistance of a working sensor changes depending on the temperature. If the device shows a break or short circuit, the part needs to be replaced. This is a consumable item that often fails.
In modern models with a display, a sensor error is often displayed as a code. The decoding of the code can be found in the instructions or on specialized forums for repairing your brand of equipment.
| Symptom | Probable cause | Nature of the failure |
|---|---|---|
| The compressor hums, but does not start | Start relay | Electrical fault |
| The refrigerator runs constantly, but does not freeze | Freon leak | Mechanical damage to the circuit |
| It’s warm in the upper chamber, there’s ice in the lower one | Clogged capillary | Impaired refrigerant circulation |
| The compressor is silent, there is light | Thermostat/Sensor | Electronics failure |
Features of the No Frost system and freezing of channels
In refrigerators with technology No Frost cold air is pumped by a fan from the freezer into the refrigerator through special air ducts. If these channels become clogged with ice, circulation stops. As a result, the food in the Antarctica freezer, and above, spoils.
The cause of freezing lies in a malfunction of the defrosting system. The heating element (heating element) may burn out, and the defrost sensor may fail. The ice does not melt, the layer grows with each cycle until it completely blocks the passage for air.
- ❄️ Check whether the fan in the freezer is spinning when the door is open (you need to press the door sensor button).
- 🌬️ Assess the strength of the air flow from the holes in the upper chamber - it may not be there completely.
- 🧊 Pay attention to the back wall: if it is covered with an uneven layer of frost, the defrosting system does not work.
The solution to the problem is complete defrosting (as a temporary measure) and replacing the burnt elements of the defrosting system (heating element, sensor, fuse). They often change the entire set at once to avoid calling the technician again in a month.
☑️ Diagnostics of the No Frost system
Influence of the environment and operating conditions
Do not forget that the climate class of the refrigerator determines the temperature range at which it can operate. If you place a refrigerator designed for a temperate climate (SN, N) in an unheated garage or on a balcony in winter, it may stop freezing. The oil in the compressor thickens, and the sensors “get confused” in the readings.
In the summer the situation is the opposite: if the room is +30°C or higher, and the refrigerator is standing next to the stove or in the sun, it may not cope with the heat flow. The compressor will work non-stop, trying to reach the set temperature, but the upper chamber will remain warm.
⚠️ Attention: Operating equipment outside the climate class specified in the passport will void the warranty and accelerate the wear of the compressor.
It is also important what the refrigerator is filled with. It is more difficult to cool an empty chamber, since the products serve as cold accumulators. But if the chamber is jam-packed, air circulation will be disrupted. Air flow must pass freely between the products.
When you need to call a technician: final summary
Only simple faults can be eliminated on your own: replace the light bulb, clean the drainage hole, defrost the unit or replace the seal. If the problem lies in refrigeration circuit (leak, blockage) or complex electronics, you cannot do without special equipment and knowledge.
Attempts at self-repair with a soldering iron and a cylinder of freon “on the knee” often end in the final breakdown of the equipment. The cost of restoration work after such attempts may exceed the cost of a new refrigerator.
If after defrosting for 24 hours the problem does not disappear, and you do not have the skills to work with a multimeter and electrical circuits, call the service. Professional diagnostics will save you time and money in the long run.
Why is it cold in the refrigerator, but the food in the upper chamber is warm?
Most likely, air circulation is impaired. In No Frost systems, the channels are clogged with ice due to a failure of the defrost system. In drip systems, cold air is heavier and falls down; if there is no forced ventilation or the thermostat is not set correctly, the upper zone may not freeze.
Can a refrigerator not freeze due to a power surge?
Yes, a power surge could damage the start relay, sensors or control board. If after the jump the refrigerator hums, but does not start, or behaves inappropriately, you need to check the electrical part.
How long does it take for the refrigerator to get cold after defrosting?
Usually it takes from 2 to 8 hours to reach operating temperature, depending on the model, the amount of food and the temperature in the room. If after 12 hours the upper chamber remains warm, there is a malfunction.
What to do if ice forms in the upper chamber?
Ice indicates increased humidity or a leak. Check the door seal, do not place hot food in, and make sure the vents are not blocked by cookware. This may also be a sign of a malfunction of the defrost sensor.