The situation when an “ice desert” suddenly appears in the refrigerator, and the food on the shelves freezes through, is familiar to many owners of household appliances. Instead of fresh herbs and soft cottage cheese, you find frozen lumps, and a thick ice crust adorns the walls. This is not just an inconvenience that forces you to defrost the chamber more often than usual, but also a signal that the thermoregulation system is not working correctly.
Excessive cold production can be caused by both trivial operating errors and serious technical breakdowns compressor or electronics. Ignoring the problem leads to rapid wear of the engine, increased energy bills and spoilage of food supplies. Understanding the reasons will help you make the right decision: call a technician or try to fix the situation yourself.
In this article we will analyze in detail the mechanics of the cooling process, consider typical malfunctions thermostats and sensors, and also touch on the nuances associated with refrigerant leaks. It is important to understand that even modern models with the system No Frost are not immune from such failures, and the diagnostic algorithm for them has its own characteristics.
Checking the thermostat settings and operating mode
Before looking for complex breakdowns, it is necessary to exclude the human factor. Often the reason lies in accidentally changed settings or an incorrectly selected operating mode. If the refrigerator begins to freeze more than usual, first check the position of the temperature regulator. In mechanical models, this is a rotary knob with numbers, where an increase in number usually means a decrease in temperature, and in electronic models, a display with precise degrees.
Pay attention to seasonal switches, if your model has them. Some refrigerators Indesit or Atlant are equipped with a “Summer/Winter” switch, which affects the operation of the circuit heater and compressor shutdown cycles. The incorrect position of this element can disrupt the operating algorithms, forcing the unit to work without stopping.
⚠️ Attention: If you have recently defrosted the refrigerator or carried out general cleaning, make sure that you have not set the regulator to maximum cooling “just in case.” This is a common mistake leading to freezing.
It is also worth checking whether the “Super Freeze” mode is activated. This function is designed to quickly freeze large volumes of fresh food and forces the compressor to work continuously. If this mode is not turned off manually (in some models it turns off automatically after 24–48 hours), the chamber will turn into a freezer.
Checking the settings is the simplest and freest stage of diagnostics. Make sure that the temperature sensors are not covered with food, as this may distort the readings for the control system.
Malfunctions of the thermostat and temperature sensors
If the settings are normal, but the refrigerator continues to “delight” you with snowdrifts, most likely the problem lies in the sensory organs of the unit. The thermostat (in mechanical models) or temperature sensor (in electronic models) is responsible for sending a signal to the compressor to stop. When this element fails, the opening circuit does not occur, and the motor runs until the emergency protection is activated or until you yourself unplug the cord from the socket.
In mechanical thermostats, contacts often stick or the bellows tube filled with freon loses sensitivity. The tube may have moved out of place or become deformed. In electronic models NTC sensors they can give erroneous resistance readings, telling the control module that the chamber is warm, although in fact there is already sub-zero temperature.
- 🔍 Symptom: The compressor hums continuously, without pausing to rest, even when it is clearly very cold inside.
- ❄️ Symptom: A thick layer of ice forms on the back wall of the main chamber, which does not have time to melt during defrost cycles.
- ⚙️ Action: The thermostat needs to be tested with a multimeter or the sensor needs to be replaced with a working one.
Replacing the thermostat is a procedure that is accessible to a person with basic repair skills, but requires caution. It is important to choose an analogue with identical parameters, otherwise the refrigerator will turn on too rarely or often.
How to check a thermostat with a multimeter?
To check a mechanical thermostat, you need to remove it, immerse the sensitive tube in water with ice (temperature about 0°C or lower, depending on the type) and ring the contacts. If the contacts do not open during cooling (the sound signal does not disappear), the thermostat is faulty and requires replacement. Important: before checking, make sure that the model of your thermostat is designed to open to cold and not to heat.
Problems with the defrosting system (for No Frost models)
In refrigerators with the system No Frost the situation with icing of food looks different. There should be no ice on the walls here, since moisture is removed through the drainage. If the food in the main chamber freezes, and a “fur coat” grows on the evaporator behind the rear panel, then the defrost cycle is broken. The ice on the evaporator blocks the air circulation channels, and the cold flow is directed directly at the food, freezing it.
The main culprits here are Defrost heating element, the defrost timer (or electronic module) and the defrost sensor. If the heating element burns out, the ice does not melt. If the timer is jammed, it does not switch the refrigerator to defrost mode. The defrost sensor can “lie”, stopping heating prematurely or not starting it at all.
System diagnostics No Frost requires partial disassembly of the back wall of the freezer or refrigerator compartment (depending on the design). It is necessary to visually assess the condition of the evaporator. If it is completely clogged with ice, and the fan hums, but does not spin due to ice, the problem is confirmed.
☑️ Diagnostics of the No Frost system
It is important not just to defrost the unit with a hairdryer, but also to find the reason why the water does not leave or the ice does not melt as usual. Otherwise, the problem will return in 1-2 weeks.
Freon leak and compressor operation
Paradoxically, a refrigerant leak can also lead to severe freezing, but only in a certain area. If there is little freon in the system, the compressor starts working longer, trying to reach the set temperature. As a result, at the beginning of the circuit (usually at the back wall, closer to the freezer), a local area with a very low temperature is formed, where everything freezes tightly, while in the far corner of the chamber it can be warmer than normal.
This condition is dangerous for compressor, which works for wear without interruption. Determining a leak visually is difficult and often requires the use of a leak detector or soap solution to check all connections and pipes. A characteristic sign may also be a hot condenser (grid at the back) only partially or its complete cooling.
| Symptom | Probable cause | Necessary actions |
|---|---|---|
| Ice only at the back wall | Partial freon leak | Searching for leaks, vacuuming, refilling |
| Ice evenly throughout the chamber | Thermostat malfunction | Replacing the thermostat |
| Dry and frozen foods | No Frost malfunction | Checking the heating element and timer |
| The compressor is hot, humming constantly | Seizing or wear | Compressor diagnostics |
Repairs associated with a sealed circuit and freon charging require special equipment and a license. It is almost impossible to eliminate the leak and properly refill the system on your own without the risk of permanently damaging the unit.
⚠️ Attention: Do not try to pierce the tubes or change the compressor yourself without skills in working with a blowtorch and a vacuum pump. Incorrect soldering will lead to the burning of the new motor in a matter of minutes.
The influence of seals and chamber tightness
It would seem that leaks should lead to an increase in temperature, but in reality everything is more complicated. If the sealing rubber on the door is worn out, dirty or deformed, warm moist air constantly enters the chamber. The cooling system detects the increase in temperature and turns on the compressor in enhanced mode. Moisture from the air condenses and freezes, forming ice, and products located close to the flow of cold air are frozen.
You can check the tightness with a simple test with a sheet of paper. Clamp the sheet with the door around the perimeter. If it pulls out easily without resistance, the seal does not fit. Also inspect the rubber for cracks, stickiness or peeling.
Often the problem is solved by thoroughly washing the seal with soapy water or heating it with a hairdryer (if it has simply lost its elasticity). In more serious cases, the sealing collar needs to be replaced.
Failures in the electronic control module
In modern refrigerators Samsung, LG, Bosch an electronic “brain” is responsible for all processes. If moisture gets on the board (for example, when washing the floor around the refrigerator, water flowed under the baseboard and was drawn in by the fan) or a power surge occurs, the module may begin to issue erroneous commands.
Symptoms of electronics failure are often chaotic: the refrigerator may either become very cold, or stop cooling, blink indicators or make beeps. In such cases, a complete reset (reboot) of the system often helps.
To perform a reset, you must unplug the refrigerator for at least 15–20 minutes. This will allow the capacitors on the board to discharge and clear errors in the controller memory. If the problem persists after switching on, there is likely a physical malfunction of the board elements or the need for flashing.
Frequently asked questions (FAQ)
Is it possible to operate a refrigerator if it gets very cold?
Short-term - yes, but this will lead to food spoilage and increased energy consumption. Long-term operation in this mode (especially without stopping the compressor) can burn out the motor-compressor, the repair of which is very expensive. It is better to eliminate the cause.
Why did ice immediately form in the new refrigerator?
When loading for the first time, the new refrigerator can work in enhanced mode until the set temperature is reached. Also check if the regulator is set to maximum by default. If ice builds up quickly and abundantly in the first day, this is a reason to contact the service under warranty.
How often do you need to defrost the refrigerator so that it does not freeze too much?
Refrigerators with a drip system require defrosting 1-2 times a year, with No Frost - as needed (usually once every 1-2 years for prevention). Frequent defrosting will not prevent thermostat failure, but will help keep the unit clean.
Does the location of the refrigerator affect the degree of cooling?
Yes. If the refrigerator is located close to the wall or next to the radiator/stove, the cooling system is overloaded, trying to compensate for external heating. This can lead to incorrect operation and local freezing. Observe the clearances for ventilation specified in the instructions.
What to do if, after defrosting, the refrigerator begins to freeze even more?
Perhaps the settings in the control system have gone wrong or there is ice left in hard-to-reach places (in the No Frost channels), which blocks the sensors. Try leaving the refrigerator turned off for a day with the doors open, then turn it on and check. If it doesn’t help, call a specialist.