The refrigerator is one of the most important household appliances in the house, ensuring the safety of food and a comfortable life. However, few people think about how exactly the cold is created inside this white box until the unit fails. The heart of any refrigeration system is the compressor, and the temperature in the chambers depends on its correct operation.
If you hear humming, clicking, or, conversely, suspicious silence, these are signals that cannot be ignored. Understanding what it does and how it functions will help you diagnose the problem faster and avoid costly repairs. In this article we will analyze in detail the design of the motor, its types and role in the overall cooling cycle. What is a refrigerator compressor for? serves and how it functions will help you diagnose the problem faster and avoid costly repairs. In this article we will analyze in detail the design of the motor, its types and role in the overall cooling cycle.
Many users mistakenly believe that cold is produced statically, but in fact it is the result of continuous circulation of the refrigerant. The driving force behind this process is the compressor unit. Without it, not a single modern refrigeration unit can operate, be it an old Soviet one Zil or the latest model Liebherr.
Main purpose and principle of operation
The main task of the compressor is to create the pressure necessary to circulate the refrigerant through the system. It works like a pump that sucks freon gas from the evaporator, where it boils and picks up heat and compresses it. As a result of compression, the gas heats up and enters the condenser under high pressure, usually located on the rear wall.
In the condenser, the refrigerant cools and turns into a liquid state, giving off heat to the environment. Then, as it passes through the capillary tube and filter drier, the pressure drops sharply and the liquid turns back into gas in the evaporator, starting the cycle all over again. This continuous process ensures cooling products in the chambers.
⚠️ Attention: Attempts to independently open the sealed compressor casing or disconnect the tubes without special equipment and skills can lead to oil release, damage to the windings and complete failure of the unit building.
Modern models may have different configurations, but the physical principle remains unchanged. The efficiency of the entire system directly depends on the performance of the motor. If the compressor is not doing its job, you will notice that the refrigerator has stopped freezing, although the motor itself may continue to hum.
Design and key elements
Externally, the compressor is a black or gray metal cylinder, most often located in the lower rear part of the refrigerator. Inside this sealed housing are an electric motor and a mechanical part, immersed in a special oil. Oil is necessary to lubricate rubbing parts and remove heat.
The main elements of the internal structure include:
- 🔧 Crank mechanism - converts the rotational movement of the engine shaft into the translational movement of the piston.
- 🔧 Piston group - directly carries out compression refrigerant.
- 🔧 Valves (suction and discharge) — ensure the movement of freon in only one direction.
- 🔧 Start-protective relay —a device that supplies a starting impulse and turns off the motor when overloads.
It is important to note that all these components operate in a confined space. That is why when replacing a compressor, professional sealing of the tubes and evacuation of the system is required. Violation of the tightness leads to the ingress of moisture and air, which causes the formation of acids and blockage of the capillary.
Why is the compressor hot?
During operation, the compressor heats up to 80-90 degrees Celsius. This is normal, since when gas is compressed, heat is released, and the electric motor also tends to heat up. However, if the temperature of the casing exceeds 100 degrees or it burns your hand instantly, this may indicate a malfunction of the thermostat or a freon leak.
Types of compressors: inverter and conventional
Two main types of compressors dominate the household appliance market today, and the difference between them is fundamental. Traditional linear (or stepped) motors operate on the “on, full power, off” principle. When the temperature in the chamber rises above the set one, the relay closes the circuit and the motor starts.
Inverter compressors, which are widely used in models Samsung and LG, work differently. They do not turn off completely after reaching the desired temperature, but only reduce the speed, maintaining the cold in constant mode. This avoids temperature changes and reduces wear of mechanical parts.
Comparative characteristics of compressor types:
| Characteristics | Linear (Normal) | Inverter |
|---|---|---|
| Principle operation | Cyclic (On/Off) | Smooth power adjustment |
| Noise level | Higher (relay clicks are heard) | Lower (works smoothly) |
| Energy consumption | Higher (inrush currents) | Lower (savings up to 40%) |
| Service life | Standard | Increased |
The choice between these types often arises when purchasing new equipment. Inverter models are more expensive, but they pay for themselves in the long run due to energy savings and quiet operation. However, repairing inverter units requires more complex diagnostics and expensive spare parts.
Diagnostics of faults: signs of breakdown
Understanding how a working unit behaves helps to notice it in time malfunction. A refrigerator compressor is a component that rarely breaks suddenly without preliminary symptoms. Most often, problems accumulate gradually.
What you should pay attention to first:
- 🔊 Extraneous sounds — knocking, clanging, metallic grinding or humming that was not there before.
- 🔥 Overheating —the motor runs continuously, without turning off for days, and gets very hot.
- 💡 Lack of cold —the refrigerator is humming, but the chambers are warm, the food spoils.
- ⚡ Knocking out plugs —when trying to start compressor, the circuit breaker in the panel is immediately triggered.
One of the common problems is the so-called “jamming” of the piston. In this case, the motor tries to start, the start relay clicks, but the shaft does not rotate. After a few seconds the relay clicks again, trying to start the unit. This situation is dangerous due to the burnout of the electric motor winding.
⚠️ Attention: If you notice that the compressor is working without stopping, do not immediately blame it for its breakdown. Often the cause lies in a freon leak or a malfunctioning thermostat. An attempt to replace the motor without eliminating the root cause will lead to repeated failure in a short time.
It is also worth checking the integrity of the housing. If traces of oil are visible on the tubes or the cylinder itself, this is a sure sign of a leak. In such cases, it is necessary not only to replace the compressor, but also to completely flush the refrigeration circuit system.
Replacing a compressor: complex repairs
Replacing a compressor falls into the category of complex repairs that require special tools. You will need a pipe cutter, torch, solder, vacuum pump and gauge station. Simply “unscrewing and screwing” will not work here, since the connection of the tubes must be absolutely tight.
The replacement process includes the following steps:
- Draining the old oil and dismantling the faulty unit.
- Installation of a new compressor with similar characteristics.
- Replacing the filter-drier (mandatory for any opening of the circuit).
- Sealing the tubes and checking the system with nitrogen for leaks.
- Evacuating the system to remove moisture and air.
- Filling with refrigerant strictly according to weight.
It is important to choose the right replacement model. They may differ in power, type of refrigerant (R134a, R600a) and mounting geometry. Installing an unsuitable motor will either lead to insufficient cooling or rapid wear of the new unit.
☑️ Readiness to replace the compressor
Prevention and extension of service life
In order refrigerator compressor to serve for a long time, you must follow the operating rules of the equipment. Often, users themselves shorten the life of the unit through improper handling. For example, frequently opening the door or loading hot products causes the motor to work in overload mode.
Key care recommendations:
- ❄️ Provide ventilation - the distance from the back wall to the wall should be at least 10 see
- 🧹 Regularly clean the condenser (grid at the back) from dust, which impairs heat transfer.
- 🍲 Do not put hot food in the chamber, let it cool to room temperature.
- 🔌 Use a voltage stabilizer if there are surges in your network electricity.
Particular attention should be paid to defrosting. Although modern systems No Frost do not require manual defrosting, a preventive shutdown once a year is still useful. This allows the oil in the compressor to warm up and evaporate possible moisture from hard-to-reach places in the system.
In conclusion, it is worth noting that a compressor is a complex technical unit that requires caring attitude. Knowledge of its structure and principles of operation will help you notice signs of trouble in time and contact specialists before repairs become economically unfeasible.
Frequently asked questions (FAQ)
How much does it cost to replace a compressor in a refrigerator?
The cost consists of the price of the unit itself (from 3,000 to 10,000 rubles depending on the model) and the work of the master. On average, repairs cost 5,000–12,000 rubles. Inverter compressors are much more expensive than linear analogues.
Is it possible to restore an old compressor or just replace it?
In domestic conditions, restoration is impossible. Factory sealing and balancing are broken when opened. Theoretically, rewinding windings or replacing valves exists, but in practice it is more expensive and less reliable than installing a new unit.
Why does the compressor get very hot?
Heating to 80-90 degrees is the norm. If the temperature is higher, the reasons may be contamination of the condenser, a freon leak, a malfunction of the thermostat, or wear and tear on the motor itself. Diagnostics by a technician is required.
How to understand that the compressor has burned out?
If you hear a click when you turn it on, the motor hums for 1-2 seconds and stops, and then the cycle repeats - most likely the piston is jammed or the starting winding is burned out. Checking with a tester will show an open circuit or short circuit.