A sudden stop of the refrigerator or a characteristic hum that turns into silence often becomes a signal of a serious breakdown requiring immediate intervention. In most cases, the culprit of this situation is compressor, which is the heart of the entire refrigeration system. Understanding the reasons for its failure allows you not only to avoid expensive repairs, but also to prevent spoilage of a large amount of food.
Many owners of household appliances mistakenly believe that the engine runs endlessly, forgetting about the complex physical processes occurring inside the sealed housing. In fact, the resource of this unit is limited, and operating conditions are often far from ideal. Let us examine in detail what factors lead to fatal consequences for the engine.
Critical problems of the cooling system and overheating
One of the most common reasons why an engine occurs is banal overheating. The compressor heats up during operation, and refrigerant circulating through the system is used to remove heat. If there is a freon leak in the circuit or a blockage in the capillary tube, the motor begins to idle, trying to gain temperature, but not receiving the necessary cooling. burning of the windings engine is simply overheating. The compressor heats up during operation, and refrigerant circulating through the system is used to remove heat. If there is a freon leak in the circuit or a blockage in the capillary tube, the motor begins to idle, trying to gain temperature, but not receiving the necessary cooling.
In such situations, the thermal relay may not be able to operate quickly enough to protect the windings from melting the insulation. Long-term operation in overload mode leads to irreversible changes in the structure of the metal and dielectric. The temperature inside the casing can exceed 150 degrees Celsius, which is a critical value for most household models.
Owners should pay attention to the temperature of the motor housing during routine checks. If it is too hot to the touch or, conversely, cold when the engine is running, this is a sure sign of a heat exchange problem.
Often the problem lies in contamination of the condenser located on the rear wall of the unit. Dust, animal hair and fat create an insulating layer that prevents normal heat exchange with the environment.
Electrical faults and surges voltage
Modern electronics are sensitive to the quality of electricity, and the refrigerator is no exception in this regard. Sharp voltage surges in the network can lead to breakdown of winding insulation or failure of starting equipment. Even a short-term high-power pulse can cause irreparable damage to the internal electrical circuit.
A particular danger is posed by frequent light outages and restarts when the compressor does not have time to completely stop and equalize the pressure in the system. Starting the engine under load with high pressure in the circuit requires a huge starting current, which often leads to burnout of the starting winding.
- 🔌 Lack of a voltage stabilizer in regions with an unstable power grid.
- ⚡ Damage to the wiring inside the apartment or oxidation of contacts in the socket.
- 📉 Using cheap surge protectors that do not provide real protection.
- 🔥 Short circuit in the power supply circuit of the refrigeration equipment itself.
⚠️ Attention: If the lights in your home flicker frequently or there are voltage drops, installing a high-quality stabilizer is a mandatory measure to protect expensive equipment.
Diagnosing electrical problems often requires the use of a multimeter. Checking the resistance of the windings allows you to identify an interturn short circuit or an open circuit. Normal resistance values are usually from 10 to 30 Ohms for the working winding and slightly higher for the starting winding, depending on the model.
Faults in the starting relay and thermostat
The starting relay plays a key role in starting the engine, supplying current to the starting winding only for a fraction of a second. If this mechanism sticks or the contacts burn out, the engine may not start the first time, hum or run jerkily. Constant attempts to start without a successful start lead to rapid heating and eventual combustion.
A similar situation occurs if there is a malfunction of thermostat or the electronic control module. If the temperature sensor “sticks” in the “on” position, the compressor operates without stopping, without entering rest mode. This leads to the accumulation of fatigue stress in the metal and overheating of the oil.
Symptoms of problems with the relay are often characteristic clicks that are heard immediately after you try to turn on the refrigerator. The motor may hum for a few seconds, and then a shutdown click is heard, after which the cycle is repeated after a certain period of time.
How to check the start relay?
Remove the relay from the compressor and shake it. If you hear the sound of a ball or loose parts inside, it means the mechanism is damaged and requires replacement. Also check the contacts for carbon deposits.
Replacing a relay is a simple procedure that you can do yourself by selecting an analogue according to the markings. However, if after replacement the problem persists, it is necessary to look for a deeper cause, perhaps in the engine itself or the refrigerant circulation system.
Mechanical wear and problems with oil
Inside the sealed compressor casing there is oil, which provides lubrication of the rubbing parts of the piston group. Over time, the oil may lose its properties, oxidize or burn, especially if the refrigerator was often transported in a horizontal position without following the rules.
Mechanical wear of pistons, rings and bushings leads to a decrease in compression. The motor is forced to run longer to reach the set temperature, which increases the overall load on the electrical part. Metal shavings formed during friction can jam the mechanism.
| Symptom | Probable cause | Consequences for the compressor |
|---|---|---|
| Severe vibration and noise | Wear bearings or shock absorbers | Engine mount destruction |
| Humming without starting | Piston group jamming | Winding breakdown from starting current |
| Oil stains around | Casing depressurization | Oil and freon leakage, dry friction |
| Continuous operation | Loss of compression (ring wear) | Chronic overheating and combustion |
It is important to note that using the wrong oil during repairs (replacing a compressor) can be a fatal mistake. Synthetic and mineral oils are not always compatible, and mixing or replacing them without flushing the system leads to the formation of paraffin plugs.
Errors during transportation and installation
Improper transportation of the refrigerator is a common cause of hidden defects that appear after time. If the unit was transported lying on its side, oil from the compressor could leak into the freon circulation circuit. When such a refrigerator is turned on without settling (at least 2-4 hours, or better yet a day), a water hammer occurs.
The liquid that gets into the cylinder does not compress, which leads to instant jamming of the piston. The engine tries to turn the shaft, the current increases significantly, and the windings burn out in a matter of seconds. Water hammer often breaks valves or connecting rods.
- 🚚 Transportation in a horizontal position without locking the doors.
- 🕰️ Turning on the appliance immediately after delivery to the room.
- 📏 Installing the refrigerator close to the wall without a gap for ventilation.
- 🌡️ Placing equipment near heat sources (batteries, stoves).
☑️ Rules for safe installation
It is also worth considering the climate class of the device. If a refrigerator designed for a temperate climate (SN, N) is installed in an unheated garage in winter or in a kitchen near a hot stove, the compressor will work with overload, trying to compensate for external temperatures.
Diagnostics and signs of imminent failure
Before the compressor finally burns out, it usually gives signals about its deplorable condition. An attentive user can notice changes in the operation of the unit and have time to take action. Early diagnosis helps save significant money.
The first sign is often a change in background sound. The appearance of a metallic clanging, knocking or unusually loud hum indicates mechanical problems. If the refrigerator starts to turn on more often than usual or the work has increased, this is a signal of loss of performance.
⚠️ Attention: The smell of burning or burning plastic in the compressor compartment area is a critical signal. Immediately disconnect the device from the network and call a technician.
For accurate diagnostics, technicians use a pressure gauge station to check the pressure in the system and current clamps to measure current consumption. Comparison of real indicators with the passport data allows you to accurately determine the condition of the unit.
Is it possible to repair a burnt-out compressor
If the motor windings are burned out, that is, a short circuit has occurred short circuit or break in the wire inside the sealed casing; repair at home is impossible. Required replacing the compressor for a new or refurbished analogue. Opening the casing and rewinding the engine at home is impractical and not economically justified.
The replacement process requires professional equipment: a vacuum pump, a filling station, a torch and tools for rolling copper. It is also necessary to replace the filter drier and evacuate the system before filling with freon.
Sometimes the cause of “combustion” is not the motor itself, but external factors. If, when testing the windings, the resistance is normal, but the engine does not start, it may simply be mechanically jammed. In some cases (rarely), it is possible to wedge the compressor by applying increased voltage, but this is a temporary measure.
Is it worth replacing the compressor on an old refrigerator?
If the refrigerator is more than 10-12 years old, replacing the compressor can cost up to 70% of the price of new equipment. In such cases, it is often more profitable to buy a new unit with a guarantee and a modern energy efficiency class.
When deciding on repairs, it is important to consider the cost of work and spare parts. A high-quality compressor from a well-known manufacturer (for example, Secop, LG, Electrolux) is not cheap, and skimping on the quality of spare parts will lead to repeated failure in a short time.
Frequently asked questions (FAQ)
Is it possible to revive a compressor if it burns out due to a surge voltage?
If the windings inside the casing burn out, resuscitation is impossible - a complete replacement of the unit is required. If only the starting relay or thermal fuse is damaged (which happens more often during surges), then replacing these external elements will bring the refrigerator back to life.
How long does the average compressor last in a modern refrigerator?
The average service life of a high-quality compressor is 10-15 years, subject to operating conditions. However, the service life can be significantly reduced due to frequent power outages, a dirty condenser or improper transportation.
Why does a new compressor burn out a short time after replacement?
Most often the reason lies in poor installation: the technician did not replace the filter drier, poorly evacuated the system or used the wrong refrigerant. It is also possible that the spare part itself is factory defective or that there is a hidden leak in the circuit.
Does a burnt-out compressor make a noise?
A burnt-out compressor can make a noise if the short circuit did not occur instantly, or if the mechanical unit is jammed and the electrical circuit is still intact. However, more often than not, when the windings are completely burned out, the engine is simply silent and does not respond to being turned on, or knocks out the machine in the panel.