The sudden discovery that the products in the refrigerator compartment lose their freshness faster than usual, and drinks are no longer pleasantly cold, causes a fair anxiety for any owner. If the temperature in the refrigerator rises, this indicates a violation of the tightness of the circuit, malfunctions of the electronics or trivial errors during operation. Ignoring the first symptoms can lead to damage to expensive food supplies and failure of the main components of the unit.
Modern models, be it Indesit, Bosch or LG, are equipped with complex control systems that must maintain the set temperature with an accuracy of degrees. However, no equipment is immune from wear and tear of parts or external factors. Understanding the physical processes occurring inside the camera will help you quickly identify the source of the problem and make the right repair decision.
In this article we will analyze in detail the mechanical and electrical causes of overheating, and also consider situations when a technician’s intervention is not required. You will learn how to carry out initial diagnostics with your own hands and which critical parameters you should pay attention to first.
Tightness failure and problems with the seal
One of the most common reasons why the temperature in the refrigerator rises, is the loss of tightness of the doorway. The rubber seal (cuff) loses elasticity over time, cracks or deforms, no longer fitting tightly to the body. Through the resulting cracks, warm air from the room constantly flows into the chamber, causing the compressor to work hard, but not cope with cooling.
You can check the condition of the seal visually and tactilely. Run your hand along the entire length of the cuff: if you feel unevenness, stickiness or see obvious tears, the part needs to be replaced. There is also a simple test with a sheet of paper: close the door, holding a strip of paper between it and the body. If the sheet is removed too easily without resistance, it means that the clamp is weakened the cold is escaping.
⚠️ Attention: Frequent slamming of the door or overloading the shelves on the door can lead to misalignment of the hinges, which also disrupts the geometry of the seal. Regularly check the tension of the loops.
To extend the service life of the rubber, it is recommended to periodically wipe it with special products or a soda solution, removing grease deposits that destroy the structure of the material. In some cases, if the rubber has simply lost its shape, but is not damaged, you can try to restore it by heating it with a hairdryer, but this is a temporary measure.
- 🧊 Regularly clean the folds of the seal from crumbs and dirt.
- 🧊 Lubricate the rubber with silicone grease every six months to maintain elasticity.
- 🧊 Make sure that the products on the door shelves do not interfere with the door's tight closure.
- 🧊 If cracks are found, immediately order a new cuff suitable for your model.
Malfunctions of the thermostat and temperature sensors
The thermostat (thermostat) is the “brain” that commands the compressor to turn on or off depending on the temperature inside the chamber. If the temperature in the refrigerator has increased and remains at a high level, perhaps the thermostat contacts are stuck in the open state, and the signal to start cooling is simply not received. In mechanical models, this is often accompanied by the absence of a characteristic click.
In modern systems No Frost and electronic control, the role of a mechanical thermostat is performed by air sensors (thermistors). They are resistors that change resistance as temperature changes. If such a sensor “lies” or shows an error, the controller may think that the chamber is already cold enough and not start the compressor. Diagnosis of such elements requires the use of a multimillimeter to measure resistance.
Often users independently turn the thermostat knob, trying to increase the cold, but if the mechanism is faulty, this will not produce results. Moreover, setting the regulator to maximum cooling with a faulty sensor can lead to freezing of the evaporator, which will create additional load on the system.
How to check the thermostat with a multimeter?
To check, you need to remove the terminals from the thermostat and “ring” its contacts. At room temperature, a working mechanical thermostat should ring (show zero or resistance close to it). If the device shows a break, the thermostat is faulty and requires replacement. In some models, to check, you need to place the sensor end tube of the thermostat in the freezer for 15 minutes.
Replacing a thermostat or sensor is a procedure accessible to experienced craftsmen, but requires precision. It is important to choose an analogue with identical parameters, since installing an unsuitable part will lead to incorrect operation of the entire unit.
Refrigerant leakage and problems with the compressor
The most serious technical reason for which the temperature in the refrigerator risesis a freon (refrigerant) leak. Freon circulates in a closed circuit, taking heat from the chamber. If a microcrack has formed in the tubes due to corrosion or mechanical damage, the gas gradually evaporates. The compressor may hum and work constantly, but there will be no cold, since there is simply nothing to circulate.
The compressor is the heart of the refrigerator. If it fails (interturn short circuit, jamming of the piston group), the refrigerant will not move through the system. Signs of problems with the compressor are often: the device is hot to the touch, a beep is heard with attempts to start and a subsequent click of the relay, or complete silence when the light in the chamber is on.
| Symptom | Probable cause | Nature of operation compressor |
|---|---|---|
| The refrigerator does not freeze | Freon leakage | Works constantly without shutting down |
| Temperature is above normal | Clogged capillary tube | Works with overheating, makes noise |
| No cooling | Compressor malfunction | Does not turn on or buzzes and clicks |
| Weak cooling | Lack of freon | Works as usual |
⚠️ Attention: Independent refilling of the refrigerator with freon is impossible without special equipment and a vacuum pump. Attempts to “break through” a blockage or solder pipes without skills can lead to complete failure of the equipment.
If you suspect a leak (for example, you see oily spots near the pipes at the back of the refrigerator or hear hissing), you must immediately disconnect the device from the network and call a technician. Operating a refrigerator with a leak can lead to compressor combustion due to lack of motor cooling or moisture entering the system.
Failures in the defrost system (for No Frost)
In refrigerators with a No Frost system, the proper functioning of the defrost system is critically important. The evaporator, hidden behind a plastic panel in the freezer, periodically becomes covered with frost. To remove it, the heating element (heating element) is turned on. If the heating element is burned out, or the defrost timer, or the defrost sensor does not work correctly, the ice does not melt, but grows.
After time, the ice coat becomes so thick that it blocks the channels through which cold air should enter the refrigerator compartment. As a result, the freezer may have a cold wall, but the temperature in the main chamber risessince the air circulation is blocked by ice. Visually, this can be seen by the narrowing of the gap between the back wall and the food or by the presence of ice at the bottom of the freezer.
Diagnostics of the defrost system requires “defrosting” the unit during the day. If, after complete defrosting, the refrigerator began to work normally and the cold appeared, but after 1-2 weeks the situation repeated itself, the problem is guaranteed to be in the defrosting system components (heating element, sensor, timer or fuse).
- ❄️ Defrosting heating element is a heating element that can burn out.
- ❄️ Defrost sensor - monitors the evaporator temperature during defrosting.
- ❄️ Timer or control module - sets the intervals for defrosting.
- ❄️ Fuse - protects the system from overheating, burns out first.
It is important not to confuse this malfunction with a fan failure. If the evaporator blower fan has stopped, cold will also not enter the chamber, although the evaporator will be evenly covered with frost. Checking the fan is usually simpler - it should make noise when the freezer door is open (in some models).
The influence of external factors and operating rules
Before sounding the alarm and looking for a repairman, it is worth analyzing the operating conditions of the device. Often increase in temperature caused by banal violations of the rules of use. For example, installing a refrigerator close to a wall or in a niche without gaps for ventilation leads to overheating of the condenser (grid at the back). If heat is not removed, cooling efficiency decreases.
Loading the refrigerator with warm food is another common mistake. By placing a pot of hot soup in the chamber, you not only risk spoiling nearby food, but also force the refrigerator to work in extreme mode for a long time. In some cases, the unit may not be able to cope with the heat influx, and the average temperature in the chamber will rise to unsafe values.
It is also worth paying attention to the location of the thermostat. If it is located next to a heat source or the sun shines directly on it through a window, the sensor will “think” that the room is hot and will incorrectly regulate the operation of the compressor.
Diagnostics and owner's action algorithm
If you encounter a problem, act consistently. First, rule out external factors: check that the door is closed tightly, make sure that the socket is working properly, and that the temperature regulator has not been knocked down by children or accidentally. Listen to the operation of the motor: if it is silent, there may be a problem in the start relay or wiring.
If the refrigerator hums, but does not cool, or cools weakly, try defrosting it completely (at least 24 hours with the doors open). This will help eliminate false sensor readings due to freezing. If after connecting to the network a day later the situation has not changed, professional repair is required.
Do not try to open a sealed circuit yourself or change the compressor without the appropriate experience and tools. These are complex components that require evacuation of the system and precise dosage of oil and freon.
Why does the refrigerator work, but the temperature does not drop?
Most often this indicates a refrigerant leak or a clogged capillary system. The compressor circulates air, but no heat exchange occurs. It is also possible for the fan to break down in No Frost systems.
Is it possible to operate the refrigerator at elevated temperatures?
For a short time - yes, if you have unloaded perishable food. Long-term operation in this mode is dangerous for the compressor, which can burn out from overheating or running “dry” (without oil cooling).
How often do you need to defrost the refrigerator for prevention?
Drip defrosting systems (crying wall) require defrosting 1-2 times a year for hygiene. No Frost systems do not require defrosting, but preventative defrosting once a year is useful for cleaning hard-to-reach places.
Does the mains voltage affect the temperature?
Yes, strong voltage surges can damage the electronic control board or the compressor start relay, which will lead to incorrect operation or stoppage of the refrigerator.
What to do if the refrigerator smells burnt?
Immediately unplug the appliance! This is a sign of overheating of the wiring, start relay or compressor windings. Further activation may lead to a fire.
Remember that timely contacting specialists at the first signs of a malfunction can often save significant money by preventing the failure of an expensive compressor. Take care of your equipment, and it will serve you for many years.