The situation when the compressor is humming, the indicators are on, but there is room temperature inside the chamber always takes you by surprise. You open the door, expecting to feel a chill, but instead you are greeted with warm air, and the food begins to spoil before your eyes. This is a classic breakdown scenario that requires an immediate response to save food supplies and prevent more serious damage to expensive equipment.
It is important to understand that a running motor does not guarantee the health of the entire system. Refrigerant circulation can be disrupted even with a good power supply. Often, equipment owners panic ahead of time, not noticing simple reasons, such as incorrect installation or lost settings. However, the problem cannot be ignored, since prolonged idling can completely damage the compressor.
In this article we will analyze in detail the main reasons why the unit stopped cooling and draw up a step-by-step action plan. We will consider both basic operating errors and complex technical faults that require the intervention of a specialist. Your task is to carry out a primary diagnosis and determine whether the problem can be solved on your own or whether you need to call a specialist.
Primary diagnosis: simple reasons for the lack of cold
Before sounding the alarm and looking for a service center number, it is worth eliminating trivial factors. It often happens that the refrigerator is working properly, but its operating conditions have changed. For example, you could accidentally touch the temperature control by switching it to the “Vacation” mode or simply turning off the cooling of one of the chambers. Check to see if the compressor on indicator on the control panel is on.
The second common factor is loading density and air circulation. If you have just filled the shelves with hot pots or filled the chamber too tightly with food, air circulation it is broken. The refrigerator takes time to cool the new volume, and in the case of hot food, it can work for hours without any visible result, trying to compensate for the heat.
It is also worth paying attention to the location of the equipment. If the unit is located too close to a wall, a heating radiator, or is exposed to direct sunlight, heat transfer efficiency decreases. Condenserlocated at the rear does not have time to cool, and the protection system may temporarily limit the operation of the compressor or reduce its efficiency.
⚠️ Attention: If you notice that the back wall The refrigerator is hot, but warm inside, this may indicate a blockage in the system or a problem with heat dissipation. Let the equipment cool by moving it away from the wall.
Faults in the defrost system and freezing of ice
One of the most common reasons why the refrigerator has stopped freezing is the formation of a “fur coat” or ice plug in the No Frost system. In models with automatic defrosting, a special cycle is responsible for removing excess moisture. If one of its elements fails, the evaporator becomes overgrown with ice, which blocks the channels for supplying cold air to the chamber.
Visually it may look like this: the compressor works almost without interruption, hums, but it’s warm inside. An ice crust freezes on the evaporator, which is hidden behind the rear panel. Air simply cannot pass through this barrier. In such cases, a whistle or wind noise is often heard, which then disappears when the fan becomes jammed with ice.
Complete defrosting is often required to solve the problem. It is necessary to turn off the device from the network, empty the chambers and leave the doors open for at least 10–12 hours (preferably for a day). This will allow the ice to completely melt and the water to drain. If cold appears after turning on, then the problem was in the defrosting system.
☑️ Correct defrosting of the refrigerator
If after defrosting the situation repeats after a few days or weeks, it means that one of the components of the No Frost system has failed. It may be Defrost heating elementthat the evaporator has stopped heating to melt the ice. Also, the defrost sensor often breaks down, which “does not see” the ice and does not start the defrosting process. Less common is a malfunction of the timer or control module, which does not switch operating modes.
Refrigerant (freon) leakage: symptoms and consequences
Refrigerant is the “blood” of the refrigerator, a substance that circulates through the tubes and takes heat from the chambers. If a microcrack forms in the circuit, the gas gradually evaporates. Unlike old models, where a leak could be noticed by oily stains, in modern units with a foamed body it is impossible to see the location of the damage.
How to understand what happened freon output? The main symptom is that the compressor works almost non-stop, trying to gain temperature, but there is no cold at all or it is very weak. In this case, the condenser (grid at the back) can remain cold or warm only at the very beginning, and then cool down, since there is nothing to circulate.
Is it possible to refuel the refrigerator yourself?
Self-refueling is impossible without special equipment (vacuum pump, manometric station, scales). In addition, the leak must be found and repaired, otherwise the new gas will also escape. This is a job for professionals.
The danger of the situation is that operating the compressor without a sufficient amount of freon or in its absence leads to overheating. The motor tries to pump gas, but cannot, which leads to increased wear and eventual combustion of the windings. Therefore, if you suspect a leak, it is better to turn off the device until the technician arrives.
Often leaks occur in places where tubes are soldered or in the foamed part of the housing (evaporator), where the metal is subject to corrosion. In the latter case, repairs may not be economically feasible, since they require opening the housing or installing an external evaporator (“crying cap”), which worsens the appearance and usable volume.
Problems with the compressor and start relay
The compressor is the heart of the refrigeration unit. If it is faulty, then there will be no cold. However, the breakdown of the motor itself is not always obvious. Often the culprit start relay is a small element that helps the engine start. If the relay is stuck or burned out, you may hear a click, a hum for a few seconds, and then a click and silence again.
In some cases, the compressor may hum but not start if its mechanical part is stuck. This is a serious breakdown that requires replacement of the unit. It is also worth checking the integrity of the windings. If an interturn short circuit occurs, the motor may operate, but not develop the required pressure to compress the freon.
Diagnostics of the compressor requires measuring instruments. The technician checks the winding resistance and current strength at startup. For the user, an important signal is the nature of the sound: a smooth hum is normal, an intermittent hum with clicks is a problem with the relay or trigger mechanism, a metal clang is a sign of mechanical destruction.
| Symptom | Probable cause | Necessary actions |
|---|---|---|
| Buzzes for 5-10 seconds, clicks and is silent | The starting relay is faulty or the compressor is jammed | Replacement of the relay, diagnostics of the compressor |
| Works constantly, no cold | Freon leak or clogged capillary tube | Looking for leaks, vacuuming, refilling |
| The motor housing gets very hot | Overload, lack of freon, malfunction | Urgent turn off, call a technician |
| Silence, indicators are on | The compressor or control module has burned out | Replacing the compressor or electronic unit |
The capillary tube and filter drier are clogged
There is a blockage in the refrigerant circulation system bottlenecks - capillary tube and filter drier. Their task is to regulate pressure and clean freon from moisture and impurities. Over time, a microscopic plug may form in the system from oil breakdown products or frozen moisture.
When clogged, circulation is disrupted: the compressor pumps gas, but it cannot pass through a narrow hole. The pressure at the compressor inlet drops and the outlet pressure rises. As a result, the evaporator does not cool and the chamber is warm. A characteristic sign of a blockage may be uneven heating of the condenser (only partially warm) and a dull, strained hum of the motor.
To eliminate this problem you need cleaning the system. The technician cuts off the old filter, flushes the system with high pressure nitrogen to dislodge the plug, and installs a new filter drier. After this, vacuuming and refilling with a new portion of refrigerant must be carried out.
⚠️ Attention: It is strictly forbidden to try to clean the capillary tube yourself by mechanical means (needles, wire). You can damage the thin walls of the tube or push debris deeper, making repair impossible.
Often blockages occur after poor-quality previous repairs, when moisture got into the system or the wrong oil was used. Also, the reason may be prolonged downtime of equipment without use.
Failure of electronics and temperature sensors
Modern refrigerators are controlled by complex electronics. Responsible for all processes is control module, which receives signals from various sensors. If the temperature sensor (thermistor) transmits incorrect data, the “brain” of the refrigerator may “think” that it is already cold inside and does not turn on the compressor, or, conversely, does not turn it off.
In two-chamber models with the No Frost system, there is often a defrost sensor. If it shows an error, the defrost cycle will not start and ice will form on the evaporator (see section above). In electronically controlled models, failures may appear in the form of flashing indicators or error codes on the display.
Diagnostics of the electronic unit requires special knowledge and circuits. Often the control module fails due to power surges in the network. In such cases, flashing or complete replacement of the control board may be required. It is also worth checking the integrity of the wires going from the door to the body - they often break when opened frequently.
Error codes
Many brands (LG, Samsung, Bosch) display error codes (for example, Er F1, E1). Always look for the decoding of a specific code in the instructions for your model, since for different manufacturers the same numbers can mean different breakdowns.
Frequently asked questions (FAQ)
Why does the refrigerator freeze but does not turn off?
If the unit works without interruption, but the temperature rises, the seal may be broken chambers (the door does not close well), the settings are incorrect (super freezing mode is turned on) or the condenser at the back is dirty. This may also indicate a beginning freon leak.
Is it possible to use a refrigerator if it does not freeze well?
For a short time - yes, if the food does not spoil. However, prolonged operation in this mode harms the compressor. If the cause is a freon leak, the motor may burn out due to overheating. It is better to find and eliminate the cause.
How long does it take for the refrigerator to start freezing after defrosting?
Usually it takes from 2 to 5 hours to reach operating temperature. At this time, you should not load the camera with food. If after 5-6 hours of operation there is no cold compressor, then there is a malfunction.
What to do if there is ice in the freezer and heat in the refrigerator?
This is a classic sign of a malfunction of the defrost system in No Frost models. Most likely, the heating element, defrost sensor or timer has burned out. Diagnostics and replacement of the defective part are required, as well as complete defrosting of the unit.
How often should the filter drier be changed?
The filter drier is changed every time the refrigerant circuit is opened (when repairing leaks, replacing the compressor). It does not require scheduled replacement after a certain time if the system is sealed.