The situation when refrigerator compartment stops cooling products, while freezer continues to work properly, is one of the most common complaints from owners of household appliances. This phenomenon often takes you by surprise, as it seems illogical: if the compressor is humming and the freezer is functioning, then the unit is alive. However, such an asymmetry of temperature conditions indicates specific malfunctions in the refrigerant circulation or control system.
In most modern models, especially those equipped with a system No Frost, the cold is generated precisely in the freezer chamber, and it is forced into the upper compartment. Disruption of this process can be caused by either a banal blockage of the channels or a serious breakdown of the compressor or a gas leak. Understanding the operating principle of your device is the first step to diagnosis.
Do not panic and immediately call a technician, as in some cases the problem can be diagnosed independently by checking basic settings and the condition of the seals. However, ignoring symptoms can lead to food spoilage and more costly repairs in the future. Let's look at the main reasons why the upper chamber stops freezing.
The principle of operation of single-compressor systems
To understand where to look for a breakdown, you need to clearly understand how the cold gets into the upper compartment. In classic two-chamber refrigerators with one compressor the evaporator is most often located in the freezer (hidden behind a plastic panel). This is where the main cooling process takes place.
Cold air from the freezer is forced into the fridge compartment using a special fan. Circulation occurs through air ducts that connect the two compartments. If the freezer is working, it means there is refrigerant in the system (at least partially) and the compressor is functioning. The problem lies precisely in the delivery of cold to the top.
It is important to consider that in different models this process is organized differently. In some cases it is used crying evaporator on the back wall of the refrigerator compartment, which periodically thaws. In systems No Frost everything is more complicated: there the air is constantly driven by a fan, and any failure in this circuit leads to an increase in the temperature in the upper compartment, while the temperature below is still minus.
⚠️ Attention: An attempt to independently open a sealed circuit or replace the refrigerant without a license and equipment is not only dangerous, but also may permanently damage the unit.
If you hear the fan working, but no air flows, the circulation channels may be blocked. Often, users pack shelves too tightly with products, blocking the technological openings for air intake and supply. This is the simplest and most easily eliminated reason.
Problems with the defrost system (Defrost)
One of the most common reasons why the upper chamber stops working is a malfunction of the automatic defrosting system. In refrigerators No Frost ice inevitably forms on the evaporator. To prevent it from turning into an ice block blocking the airflow, the defrost heating element is periodically turned on defrost heating element.
If this mechanism breaks down, the evaporator becomes so overgrown with ice that the fan stops blowing air through it into the refrigeration compartment. The freezer may continue to freeze, since the cold air remains there, but the circulation to the upper chamber stops completely. The main culprits here:
- ❄️ Defrost heating element — the heating element could burn out and stop heating.
- ⏱️ Timer defrost —the device that regulates the freezing and defrosting cycles could “stick” in the cooling mode.
- 🌡️ Defrost thermostat - the sensor, which should turn off the heating element when a certain temperature is reached, could fail.
It is difficult to diagnose this problem visually, since the evaporator is hidden behind the back wall of the freezer. However, an indirect sign is that the refrigerator begins to work longer than usual, trying to gain temperature, or an uneven layer of ice is visible on the back wall of the freezer.
How to check the defrost heating element?
To check, you will need a multimeter. You need to get to the heating element (disassemble the freezer), disconnect the wires and ring the element. If the resistance is infinitely high, the heating element has burned out and requires replacement.
The solution to the problem in this case will be to replace the faulty element of the defrost circuit. This is a standard repair procedure that returns air circulation to normal. After replacing parts, the unit must be defrosted for 24 hours so that all accumulated ice melts.
Compressor malfunctions and loss of power
A more serious situation occurs when the compressor, although it starts, does not develop enough power to provide cold in both chambers. This often happens when turn-to-turn short circuit motor windings or the piston group wears out its life.
In such cases, the refrigerant pressure is only enough to cool the evaporator in the freezer chamber (which is located closer to the beginning of the cycle), but before the refrigeration compartment Freon simply does not arrive in the required condition. The symptoms of such a breakdown are specific:
- 🔊 The compressor works continuously, without turning off for rest.
- 🔥 The side walls of the refrigerator (condenser) are barely warm or cold.
- 📉 The temperature in the freezer may be slightly higher than normal (for example, -10°C instead of -18°C), and at the top it is completely positive.
Another reason may be clogged capillary tube. Oil oxidation products or moisture entering the system form a plug. Freon circulates in a small circle or does not pass beyond a certain area. Often, gurgling or hissing is heard in the area of the pipelines.
Repair in case of problems with the compressor or a clogged system requires calling a specialist. The system will need to be evacuated, the filter drier replaced and charged with new refrigerant. It is impossible to carry out these operations on your own without equipment.
Refrigerant leak (Freon)
Leak freon is perhaps the most insidious reason why the upper chamber stops freezing. The refrigerant circulates in a closed circuit, and if a microcrack appears in the system, the gas gradually evaporates. Since the evaporator in the freezer is located at the beginning of the circuit, it is cooled by the last remaining freon, and the coolant no longer reaches the upper chamber.
It is almost impossible to determine a leak visually, since freon is colorless and odorless. However, there are characteristic signs:
- The refrigerator works almost non-stop.
- The condenser grille at the back remains cold.
- In the freezer, only a small “fur coat” may appear at the entrance, and the rest of the evaporator is dry.
Often leaks occur in the foamed part of the housing (internal pipelines) or in soldering areas hidden by thermal insulation. In older models, the cause could be corrosion of the metal parts of the evaporator. In modern refrigerators, the tubes are often made of aluminum, which also makes them vulnerable to mechanical damage (for example, due to careless defrosting with a knife).
| Symptom | Probable cause | Action |
|---|---|---|
| Compressor silent | No electricity, compressor or relay burned out | Check the socket, replace the relay |
| The compressor hums, but does not start | The compressor is jammed or the starter is burned out | Replacing the start relay, repairing the compressor |
| Works without stopping, no cold | Freon leak or blockage | Call a technician to find a leak |
| The freezer is freezing, the top no | No Frost system malfunction or clogged channels | Defrost, checking heating element and fan |
Clogged air supply channels
In models with the system No Frost air moves through special plastic boxes and channels. Over time, debris, crumbs, pieces of plastic from food, or even small insects can get into them. This creates a mechanical obstacle to the flow.
Also, the channels can freeze from the inside if the defrosting system does not work correctly (see section above). Ice blocks the cross-section of the air duct, and warm air from the refrigerator compartment cannot go down for cooling, and cold air cannot rise up.
To eliminate this problem, it is often enough to completely defrost the refrigerator. It is necessary:
- 🔌 Disconnect the device from the network for at least 24 hours (preferably for two days).
- 🚪 Leave the doors of all chambers completely open.
- 💧 Place containers for draining water or lay down rags.
If after this procedure the refrigerator started working normally, but after a week or two the situation repeated itself, then the problem is not a one-time freezing, but a malfunction of the sensors or heating elements that need to be changed.
⚠️ Attention: Never use a hairdryer or hot water to speed up the defrosting of ice inside the channels. A sudden change in temperature can lead to cracks in the plastic box or damage to the evaporator tubes.
Malfunction of the thermostat or sensors
The refrigerator electronics control the temperature based on sensor readings. In two-chamber models, there may be one thermostat (in the refrigeration chamber), which turns off the compressor when the desired temperature is reached there. If this sensor “lies” and shows that there is already cold (although in fact it is warm), the compressor will not turn on or will turn off too early.
As a result, the freezer, receiving cold according to the residual principle or having its own evaporator, still maintains the temperature, but the upper chamber is already warm. In modern models with electronic control, separate temperature sensorss can be responsible for each compartment. The output of one of them leads to desynchronization of operation.
Diagnostics of sensors is carried out with a multimeter by measuring their resistance at different temperatures. If the readings do not correspond to the technical data sheet of a particular model (for example, Indesit, LG, Samsung), the part must be replaced. This is a relatively inexpensive repair.
☑️ Diagnostics before calling a technician
Problems with the seal and thermal insulation
Sometimes the reason lies not inside, but outside. If sealing rubber the door of the refrigeration chamber is worn out, dirty or deformed, warm air from the room constantly enters the chamber. The compressor is trying to cool it, but there is not enough power.
Less warm air gets into the freezer (since cold air is heavier and sinks down, and warm air remains at the top, at the refrigerator door), so the temperature there can remain normal as long as it is above zero. You can check the seal using a sheet of paper: hold it with the door and try to pull it out. If it is pulled out without effort, the seal is broken.
It is also worth checking whether the refrigerator is level. If it is tilted forward, the door may not close completely on its own. Adjusting the legs of the refrigerator often solves the problem of a loose fit.
In conclusion, it is worth noting that if simple methods (defrosting, checking temperature settings, cleaning the seal) do not help, and the upper chamber still does not cool, professional intervention is necessary. Long-term operation of the refrigerator in the “undercooling” mode is harmful to the compressor, which in such conditions wears out.
Is it possible to operate the refrigerator if the upper chamber does not freeze?
Short-term - yes, if you put the food in the freezer or use it quickly. However, prolonged operation in this mode will lead to damage to the compressor due to continuous operation without shutdowns. In addition, bacteria will begin to multiply in a warm chamber.
How long should defrosting last to remove the ice jam?
To completely melt the ice in hidden channels and on the evaporator, it is recommended to unplug the refrigerator for at least 12, and preferably 24, hours. A shorter defrosting may not eliminate the problem completely.
Why did the refrigerator work after defrosting, but after 3 days it stopped again?
This is a sure sign of a malfunction of the defrosting system (heating element, timer or sensor). Ice accumulated again and blocked the channels. The burnt element of the defrosting circuit needs to be replaced.
Does the amount of food in the refrigerator affect its operation?
Yes. If there is too much food and it blocks the ventilation openings, air circulation is impaired. Also, a full refrigerator requires more energy for cooling, but holds the temperature better when the lights are turned off.