The refrigerator is one of the most important household appliances in every home, ensuring the safety of food and the comfort of residents. When this unit suddenly stops cooling, the owner’s first thought is often panic and the question of the cost of the new device. However, the situation is not always critical, and understanding why refrigerator compressors break can help avoid costly diagnostic errors.
The heart of the refrigeration system is compressorwhich ensures the circulation of refrigerant in a closed circuit. It is this unit that experiences maximum loads during operation, working cyclically: turning on to create cold and turning off when the set temperature is reached. Violation of any of its operating conditions leads to overloads, overheating and, ultimately, failure.
In this article we will analyze in detail the main technical and operational factors leading to breakdowns of the motor-compressor. You will learn about hidden threats, such as the quality of electricity and the condition of heat exchangers, and also receive practical advice on caring for equipment.
Overheating and heat transfer failure
One of the most common reasons for the failure of a compressor unit is simple overheating. The motor-compressor heats up during operation, and a condenser is provided in the design to remove heat (black grille on the back or sides of the housing). If this heat exchanger is clogged with dust, pet hair, or pressed tightly against the wall, the temperature inside the system begins to rise.
When the temperature rises above permissible limits, the oil that lubricates the rubbing parts loses its viscous properties. This leads to the fact that mechanical wear the piston group accelerates significantly. In critical situations, the oil can coke, turning into a solid mass, which causes jamming of the piston and combustion of the electric motor windings.
⚠️ Attention: Never install the refrigerator close to a wall or furniture. The minimum gap for air circulation should be at least 5-7 centimeters, otherwise the risk of overheating increases many times over.
It is also worth considering the condition of the room itself. If the refrigerator is placed next to a radiator, gas stove, or in direct sunlight, the system is forced to work almost without interruption, trying to compensate for external heat. Constantly operating at the limit of capabilities is a sure way to reduce the service life of equipment.
Power supply problems and power surges
Modern household appliances, despite manufacturers' assurances of protection, remain extremely sensitive to the quality of the supplied electricity. Electrical networks often experience voltage surges caused by the switching on of powerful consumers or accidents at substations. A sharp surge in voltage can break through the insulation of the compressor motor windings.
Situations are especially dangerous when the voltage in the network drops below normal. At low voltage, the starting current increases, but the engine cannot develop the required speed. This leads to the fact that start-up protection relay does not work correctly, and the windings begin to heat up intensely until their thermal destruction occurs.
To protect expensive equipment, it is recommended to use voltage stabilizers or surge protectors with a shutdown function at critical values. This is especially true for old houses and suburban areas, where the quality of the electrical network often leaves much to be desired.
What happens inside during a power surge?
During a sharp surge in voltage, the insulation of the copper winding can be broken, which causes a short circuit. As a result, not only the motor burns out, but the electronic control board often fails if it does not have proper protection.
In addition, frequent power outages are also harmful. Each compressor start is a peak load. If the refrigerator is turned off and turned on after 10 seconds, the refrigerant in the system has not yet equalized pressure. Starting in such conditions requires enormous effort from the engine, which leads to its premature wear.
Natural wear and resource depletion
Any mechanical unit has its own service life. The refrigerator compressor is no exception. During long-term operation, the natural wear and tear of rubbing parts occurs: pistons, cylinders, valves and bearings. The average service life of modern compressors is from 10 to 15 years, but under intense load it can be less.
With age, the metal gets tired, the gaps between parts increase, which reduces the efficiency of refrigerant compression. The compressor is forced to work longer to reach the desired temperature in the chambers. This phenomenon is called decrease in performance and is often accompanied by an increase in noise and vibration.
The table below shows the approximate service life of various types of compressors under normal operating conditions:
| Compressor type | Average resource (hours) | Service life (years) | Features |
|---|---|---|---|
| Normal (linear) | 15 000 - 20 000 | 7-10 | Works jerkily, noisy |
| Inverter | 30 000 - 40 000 | 10-15 | Smooth operation, quiet |
| Linear inverter | 25 000 - 35 000 | 10-12 | Few moving parts |
| Piston (old type) | 10 000 - 15 000 | 5-8 | High wear, noise |
When service life exhausted, repairs often become economically unfeasible. Replacing an old motor with a new one can cost up to 70% of the price of a new refrigerator, so in such cases, owners often decide to purchase new equipment.
Faults in the refrigerant system
The refrigeration circuit is a sealed system in which freon gas and special compressor oil circulate. If refrigerant leaks through microcracks in the pipelines or evaporator, the compressor begins to pump a rarefied mixture. This leads to the fact that the motor does not receive sufficient cooling from the passing gas and overheats.
An even more dangerous situation occurs when moisture gets inside the circuit. Water can penetrate there due to poor-quality previous repairs or through leaky connections. In the cooling system, moisture freezes, forming ice plugs in the capillary tube, or reacts with oil, forming acid.
Acid environment corrodes the insulation of the electric motor windings from the inside, which inevitably leads to a short circuit. Moisture also causes corrosion of the metal parts of the valve group, breaking their tightness.
⚠️ Attention: If after repairing the refrigerator it stopped cooling after a few months, perhaps the technicians did not replace the filter drier, and moisture entered the system, causing corrosion of the compressor.
To prevent such problems, it is necessary to monitor the integrity of the internal evaporator (especially in the No Frost freezer). Punctures during defrosting with a knife are a common cause of moisture and air entering the system, which is detrimental to the compressor.
Malfunction of the thermostat and sensors
The operation of the compressor is controlled by electronics or a mechanical thermostat. If the temperature sensor fails and begins to show incorrect data (for example, that the chamber is too warm), it gives a command to keep the motor running continuously.
The refrigerator in this mode works non-stop, trying to achieve non-existent cold. The compressor does not have time to cool down during pauses, the temperature of the windings rises, the oil loses its properties, and thermal breakdown occurs. This is a classic example when a small part (sensor) kills the most expensive component.
Symptoms of such a malfunction are:
- ❄️ Continuous operation of the refrigerator without shutdown cycles.
- ❄️ The appearance of ice in the main chamber or, conversely, defrosting of food.
- ❄️ Strong heating of the motor housing at the rear of the unit.
- ❄️ Characteristic smell of burning or scorched insulation.
Timely replacement of the thermostat or electronic control module can save the compressor from combustion. If you notice that the refrigerator is humming for days on end, you need to immediately check the serviceability of the sensors.
Mechanical damage and improper transportation
The compressor is attached to the frame of the refrigerator on shock-absorbing springs or rubber feet. In case of careless transportation, shock or strong vibration, these fasteners may be damaged. As a result, the motor begins to vibrate and hit the housing, which leads to the breakage of the internal copper tubes.
The violation of the tightness sealed pipesthrough which freon is taken in and released is especially critical. If air gets into the system, the compressor will start to overload. Also, during transportation, the refrigerator should not be placed on its side or shaken, since oil from the crankcase can flow into the refrigerant circulation circuit.
Starting a compressor with oil in the circuit (water hammer) often leads to instant jamming of the piston group. The motor hums, tries to start, but physically cannot turn the shaft, which causes a sharp jump in current and burnout of the starting winding.
☑️ Rules for safe transportation
Frequently asked questions about compressor breakdowns (FAQ)
Is it possible to repair a burnt-out compressor or just replace it?
In 99% of cases, when the windings burn out or mechanical jamming, the compressor must only be replaced. Rewinding the motor at home is impossible due to the need for evacuation and special soldering, and the cost of such work often exceeds the price of a new unit.
Why does the compressor turn on and then immediately turn off?
This is a sign of a malfunction of the starting relay or the compressor itself. The relay tries to start the motor, the current increases sharply, the thermal protection is triggered and opens the circuit. If the motor hums for 3-5 seconds and clicks, it is most likely jammed or the winding is broken.
Does the amount of food in the refrigerator affect the operation of the compressor?
Yes, it does. An empty refrigerator heats up faster when the door is opened, since the air does not have the heat capacity of the food. However, packing the chambers too tightly interferes with the circulation of cold air, causing the compressor to work longer. It is optimal to fill the chamber by 60-70%.
How to extend the life of a compressor in hot weather?
In the summer, when the room temperature is above 30 degrees, the efficiency of heat transfer decreases. It is recommended to ventilate the kitchen more often, do not place heating devices near the refrigerator and ensure that the back grill is clean. You can also reduce the temperature inside the chambers.