Refrigerator is one of the most important household appliances in every home, ensuring the safety of food for a long time. However, few people think about what exactly causes the low temperature to be maintained inside this metal box. The heart of the entire cooling system is refrigerator compressor, without which the operation of the unit would be impossible. Understanding its purpose helps not only to take care of the equipment, but also to correctly diagnose breakdowns.
If you have ever heard a characteristic humming sound coming from the back wall of a working appliance, know that this is it, the engine put into operation. Motor-compressor performs a role a pump that forcibly circulates refrigerant through a closed system circuit. It is this circulation that allows heat to be removed from the inner chamber and dissipated into the surrounding space through the condenser grille.
In the modern world, there are many models of refrigeration equipment, from simple single-chamber devices to complex multi-door systems with function No Frost. Despite the differences in design and additional functionality, the operating principle of the main power unit remains fundamentally similar. Let's look in detail at how this unit works and why it is so critical for the entire system.
The basic principle of operation of the compressor
The main task for which the compressor serves is to create a pressure difference in the cooling system. It compresses the refrigerant gas coming from the evaporator and sends it under high pressure to the condenser. During the compression process, the temperature of the gas increases significantly, which allows it to effectively transfer heat to the room through the radiator on the rear wall.
The process occurs cyclically and continuously until the thermostat registers the achievement of the set temperature inside the chambers. Piston group, located inside the sealed housing, makes reciprocating movements, providing the necessary pressure. Without this mechanical effect, freon would simply stand in the tubes, not performing its heat exchange function.
⚠️ Attention: Never try to open the sealed compressor housing yourself. There may be oil under pressure inside, and the refrigerant itself, if in contact with an open flame or spark, can be hazardous to health.
It is worth noting that the efficiency of operation directly depends on the tightness of the system. If a microcrack forms somewhere, the pressure will drop, and motor will work non-stop, trying to compensate for the loss of cold, which will quickly lead to its overheating and failure.
Design and internal components
Externally, the compressor is a black metal cylinder or barrel located at the lower rear of the refrigerator. However, hidden inside this case is a complex mechanism consisting of several key elements. The basis is electric motorwhich converts electrical energy into mechanical movement of the shaft.
The second important element is the compressor unit itself, which can be piston, linear or inverter. In classic models, the piston compresses the gas, and the valves regulate the direction of its movement. All these parts are immersed in a special oil, which lubricates the rubbing surfaces and seals the gaps between the piston and cylinder.
The third component is a start-up relay. It serves to start the motor and protect the windings from overcurrent. If you hear a clicking sound before the refrigerator starts or stops, this is what works. Also important are the copper tubes coming out of the housing: one sucks in the gas, the other pumps it under pressure. relay. Also important are the copper tubes coming out of the housing: one sucks in the gas, the other pumps it out under pressure.
Why is the compressor hot?
During the compression of gas, a large amount of thermal energy is released. In addition, the electric motor itself heats up during operation. The normal case temperature is up to 60-70 degrees Celsius, but when touched, the hand can feel intense heat.
The build quality of the internal components directly affects the level of noise and vibration. Modern manufacturers pay special attention to balancing rotating parts and using noise suppressors on tubes.
Types of compressors in modern refrigerators
Technology does not stand still, and today there are various types of engines on the market, each of which has its own operating characteristics. Understanding the differences will help you choose the equipment that is best suited for your living conditions and budget.
The most common types are:
- 🔹 Piston —the classic version with a crank mechanism, reliable and repairable, but noisier.
- 🔹 Inverter —work without constant switching on and off, smoothly regulating power, which saves energy and reduces wear.
- 🔹 Linear - use reciprocating motion of the piston without rotational mechanisms, are compact and have a low level of vibration.
Inverter models, such as Digital Inverter from Samsung or Linear Inverter from LG, are considered more modern. They last longer due to the absence of starting currents, which are the main cause of winding burnout in conventional motors. However, their repair requires high qualifications and expensive equipment.
| Compressor type | Noise level | Energy consumption | Service life |
|---|---|---|---|
| Piston | High | Standard | 10-15 years |
| Inverter | Low | Economic | 15-20 years |
| Linear | Average | Economic | 15-20 years |
Role in the cooling cycle and heat transfer
To understand what a refrigerator compressor serves in a global sense, you need to consider the full refrigerant circulation cycle. After leaving the compressor, the hot gas under high pressure enters the condenser (black grille at the back). There it cools and turns into liquid.
The liquid freon then passes through a capillary tube, where its pressure drops sharply and it enters the evaporator inside the chambers. Here the refrigerant boils and absorbs heat from the food. After this, gaseous the refrigerant is again sucked in by the compressor, and the cycle repeats.
Without a compressor, this process would be impossible, since natural circulation is not enough for effective cooling of large volumes. It acts as a “heart” that pumps “blood” (freon) through the “vessels” (tubes) of the system.
⚠️ Attention: If you notice that the refrigerator has stopped freezing, but the compressor is running continuously and is very hot, there may be a freon leak or a clogged capillary system. Operation in this mode is dangerous.
The efficiency of heat transfer also depends on the cleanliness of the condenser. If it is clogged with dust, the compressor has to work with increased load to remove heat, which reduces its service life.
Diagnostics of faults and signs of breakdown
Sooner or later, even the most reliable unit may fail. There are a number of signs by which you can determine that the refrigerator compressor is faulty or malfunctioning. Timely detection of a problem can save food and costly repairs.
Main symptoms of problems:
- 🔸 Lack of starting —the refrigerator is silent, there is light inside, but the engine hum is not heard. Often the reason is the starting relay or a break in the winding.
- 🔸 Continuous operation —the motor hums without interruption, without turning off for rest. This may indicate a freon leak or loss of chamber tightness.
- 🔸 Knock and vibration —strong shocks during startup or during operation indicate mechanical destruction of the internal parts of the piston group.
You should also pay attention to the burning smell. If the back wall smells of burnt insulation, this is a sure sign of overheating electrical part the engine. In such cases, you must immediately disconnect the device from the network.
☑️ Compressor diagnostics
Operating rules to extend service life
In order for the compressor to last as long as possible, you must follow simple rules for operating the refrigerator. First of all, this concerns the installation of the device. You cannot place the refrigerator close to the wall; you must leave a gap of at least 10 cm for free air circulation around the condenser.
The second rule is not to load hot foods into the chambers. This creates excess heat load, forcing motor to work at the limit. You should also defrost the refrigerator regularly (if it is not a No Frost system), since a thick layer of ice on the evaporator impairs heat transfer.
The third rule is careful handling during transportation. After moving, you should not turn on the refrigerator immediately. The oil must drain into the compressor crankcase, otherwise a hydraulic shock is possible, which will damage the piston group. The standing time depends on the time of year and the position during transportation.
Frequently asked questions (FAQ)
Is it possible to replace the compressor with refrigerator yourself?
Theoretically it is possible, but in practice it is extremely difficult without special equipment. To replace you need:
1. Pump out the old freon.
2. Cut off the tubes and solder a new compressor (you need a torch and solder).
3. Evacuate the system.
4. Fill in the exact amount of refrigerant.
Without skills and tools, it is better to call a technician.
Why does the compressor get very hot during operation?
Heating to 60-80 degrees is the norm for a running engine. However, if it is hot to the point that it is impossible to touch it with your hand, this may indicate:
- Clogged condenser with dust.
- Refrigerant leak.
- Malfunction of the thermostat.
- Wear of the thermostat itself. motor.
How long does a compressor last on average?
The average service life of modern compressors is from 10 to 15 years. Inverter models can operate for up to 20 years or more. However, the real figure greatly depends on the quality of electricity in the network, the frequency of voltage drops and operating conditions (room temperature, cleanliness of the heat exchanger).
What to do if the compressor hums, but does not start?
Most likely, the problem is in the start relay or jammed piston group. Sometimes lightly tapping the relay body helps (the “resuscitation” method), but this is a temporary solution. If the motor hums for more than 10-15 seconds and does not start, it urgently needs to be de-energized so that the windings do not burn out.