The situation when lower chamber the refrigerator continues to freeze food, and the upper compartment suddenly becomes warm, causes panic in anyone housewives. This is a classic symptom of poor refrigerant circulation or a malfunction in the temperature control system. In modern models with a system No Frost or static cooling, the reasons may be radically different, but the result is the same - the risk of food spoilage.
Before calling a technician, it is worth understanding the basic principle of operation: cold air either naturally falls down or is forced by a fan. If this process is disrupted, the upper zone stops cooling. In 80% of cases, the problem lies in freezing of the evaporator or failure of one of the sensors, and not in a complete breakdown of the compressor. Independent diagnostics will help save time and money.
Sometimes the reason is trivial: you simply loaded the shelves too tightly, blocking air access to the sensor. However, if the food is laid out correctly and the temperature does not drop, you will have to look deeper. It is important not to ignore the first signs of a malfunction, since prolonged downtime of equipment in abnormal mode can lead to failure of an expensive compressor.
Impaired air circulation and freezing of the evaporator
The most common reason why the upper chamber does not cool is the formation of a “snow coat” on the evaporator. In refrigerators with a system No Frost moisture released by food settles on the cold element and must be thawed periodically. If this process is disrupted, the ice blocks the channels through which cold air enters the main compartment.
As a result, the fan circulates air inside the freezer, but it simply does not reach the top. You can hear the engine humming, but there is no cold above. This happens especially often if the door seal is worn out and allows warm, moist air inside, accelerating the freezing of ice.
⚠️ Attention: An attempt to break off the ice with a knife or sharp objects will lead to a breakdown of the evaporator tubes. This is a fatal failure, requiring replacement of the entire assembly and complex soldering.
To fix the problem, complete defrosting of the refrigerator is often required. You need to turn off the device from the network, open the doors and leave it for at least 24 hours. This is the only way the ice in hard-to-reach channels will have time to completely melt.
Malfunctions of the defrost system (Defrost)
If after a day of defrosting the refrigerator worked like new, but a week later the situation repeated itself, it means that the automatic defrosting system has failed. It consists of several key elements, and the failure of any of them leads to ice fouling on the evaporator.
First of all, check Defrosting heating element. This is a heating element that turns on on a timer and melts the ice. If it burns out, the ice does not melt and blocks the air dampers. Also, the defrost sensor often breaks down, which “does not see” that the evaporator has already warmed up, or the timer, which simply does not give a command to turn on the heating.
How to check the heating element without disassembling?
You cannot directly check the heating element without removing the back panel of the freezer. However, an indirect sign of its malfunction is the absence of a click on the timer and the constant hum of the compressor when the upper chamber is warm.
Replacing these parts requires partial disassembly of the inside of the freezer. It is necessary to remove the plastic casing, get to the evaporator and test the circuit with a multimeter. Usually they change the entire set: heating element, sensor and timer (or control module) to avoid calling the technician again in a month.
Problems with the fan and dampers
In two-chamber models, the fan is responsible for moving air masses. If it stops spinning, cold air remains in the freezer, and room temperature is set in the upper compartment. There may be several reasons for the stop: wear of the bearings, freezing of the blades or breakdown of the electric motor.
Often the fan simply jams due to frozen ice. In this case, you may hear extraneous noise, crackling or humming coming from the rear wall. The blades are trying to turn, but the ice crust prevents them from doing so.
- ❄️ Check to see if the ice is frozen on the fan blades.
- 🔌 Make sure there are no wires or labels wrapped around the impeller.
- 🔊 Listen: if the motor hums, but does not spin - it is jammed or burned out.
- 🌬️ Evaluate the permeability of the air ducts: they should not be clogged with products.
In addition to the fan, air dampersplay an important role. These are special valves that regulate the amount of cold supplied. If the damper mechanism is stuck in the closed position, air will physically be unable to enter the upper chamber. In some models Indesit or Atlant this is a common mechanical problem.
Freon leakage and clogged capillary tube
More serious problems are associated with violation circuit tightness or (clogged) system. If in the refrigerator a micro-leak of refrigerant has occurred, its quantity is only enough to cool the first section of the circuit - usually the freezer. Freon simply does not reach the top, losing its cooling capacity.
Signs of a leak or blockage often appear gradually. First, the upper chamber begins to cool worse, then the temperature in it becomes comparable to room temperature. In this case, the compressor can work almost non-stop, trying to achieve the specified parameters, but to no avail.
Clogging of the capillary tube occurs due to moisture or debris entering the system. An ice or oil plug forms, blocking gas circulation. Unlike a leak, if there is a clog, the compressor may cycle or make unusual noises, and the condenser on the back wall will only be partially hot.
Only a specialist with a pressure gauge manifold can diagnose these faults. It will connect to the service fitting and measure the pressure in the system. Low pressure will indicate a leak, and abnormal behavior of the arrows will indicate a blockage.
Failures in the electronic control module
Modern refrigerators, such as Samsung, LG or Boschare controlled by complex electronics. If the “brain” of the device malfunctions, it may incorrectly read sensor readings or not supply voltage to the heating element and fan. In this case, everything is mechanically correct, but the operating logic is broken.
Often the problem lies in oxidation of the contacts or a power surge in the network. The electronics begin to “glitch”: either it turns on the super-freezing mode, or it completely turns off the cooling of the upper chamber. Sometimes a simple restart of the system helps.
To reset the error, you need to unplug the refrigerator from the outlet for 15–20 minutes. Then turn it on and check the operation. If after a few hours the problem returns, most likely the control module itself or one of the temperature sensors connected to it has failed.
The table below shows the main symptoms and probable causes for quick reference:
| Symptom | Probable cause | Complexity repair |
|---|---|---|
| The freezer is working, the top is warm | Clogged air ducts, fan malfunction | Medium |
| Ice on the back wall of the freezer | Faulty defrost system (heating element, timer) | Medium/High |
| The compressor hums continuously | Freon leak, capillary clogged | High (a technician is needed) |
| The cold disappears periodically | Electronics failure, temperature sensor | High (module replacement) |
Operating errors and external factors
The breakdown does not always lie inside the unit. Sometimes we ourselves create conditions under which the upper chamber ceases to perform its functions. For example, installing a refrigerator close to a wall or in a niche without gaps disrupts heat transfer. The compressor overheats and cannot provide the required temperature difference.
The room temperature also affects. If the refrigerator is located near a radiator, stove, or in direct sun, the cooling system may not be able to cope with the heat flow. In such conditions, the upper chamber will always be warmer than normal.
⚠️ Attention: Do not place hot foods in the refrigerator. The evaporation of a large volume of moisture instantly leads to freezing of the air supply channels.
Check the position of the temperature regulator. On some older models, one control controls both chambers, and moving the slider to the minimum may turn off the cooling of the upper compartment. Make sure that you do not accidentally switch the refrigerator to the “Vacation” or “Super Freeze” mode.
Algorithm of actions when a malfunction is detected
If you notice that it is warm in the upper chamber, do not rush to throw away the food or call for service. First, perform basic diagnostics that will help narrow your search or even solve the problem without cost.
Start with a visual inspection and listening to the operation of the unit. Are there any extraneous sounds? Is the light on? Is the fan working? These simple observations will give the technician over the phone primary information to estimate the cost of the work.
☑️ Primary diagnostics
If after complete defrosting (24 hours with the doors open) the refrigerator started working normally, but after 5-7 days the problem returned - get ready to repair the system defrost. If defrosting did not help at all, and the cold did not appear even temporarily, there is likely a freon leak or a compressor breakdown.
When you need to call a professional technician
Independent repair is possible only in cases that do not require intervention in a sealed circuit or complex electronics. You can replace a light bulb, wash the drain hole, or even change a fan if you have the skills.
However, if we are talking about soldering tubes, filling freon, replacing a compressor, or reflashing a control module, you need a specialist. A qualified technician has equipment for evacuation of the system and knows the nuances of working with various refrigerants (R600a, R134a).
Attempting independent soldering without nitrogen or incorrect filling with gas can completely “kill” the compressor, the cost of which is up to 70% of the price of a new refrigerator. Therefore, weigh the risks: saving on calling a technician can lead to the purchase of new equipment.
Why, after defrosting, did the refrigerator stop cooling again after a week?
This is a sure sign of a malfunction of the defrost system. Ice has accumulated again and blocked the channels. Most likely, the heating element of the evaporator heater has burned out or the defrost sensor has failed.
Is it possible to operate the refrigerator if it does not cool? upper chamber?
It’s possible for a short time, the food in the freezer will not be damaged. However, long-term operation in this mode is harmful for the compressor, which works without stopping. In addition, bacteria will begin to multiply in the warm chamber.
How much does the repair cost if you need to replace the heating element or sensor?
The cost consists of the price of the spare part and the work of the technician. Replacing a heating element or sensor is a repair of medium complexity. Prices may vary depending on the model of the refrigerator and the region, but it is cheaper than repairing a compressor.
How to understand that freon has leaked?
Main signs: the compressor works constantly or for a very long time, the condenser (grid at the back) cold or only partially warm, it may be cold in the freezer, but the food does not freeze completely, it is warm in the upper chamber.