When choosing a new household appliance for the kitchen or trying to understand the reason for the breakdown of the old one, we are often faced with technical characteristics that seem complex. One of the main parts that determine the reliability, efficiency and noise level of the device is the engine that creates the cold. It is its type that determines how long the equipment will last and how quiet its operation will be at night. Many buyers still focus only on the volume of chambers and design, forgetting to look at the product data sheet.
The modern market offers many options, and manufacturers are not always willing to share details about the “heart” of the refrigerator. However, understanding what compressors are installed on refrigeratorswill help you avoid disappointment and unnecessary expenses on repairs. In this article, we will analyze in detail the design of various units, their pros and cons, and also consider why some models hum, while others operate almost silently.
Principle of operation and purpose of the compressor
The compressor is the main unit of the refrigeration circuit, performing the function of a pump. Its main task is to compress the refrigerant and circulate it through a system of tubes. Without this mechanism, heat transfer from the interior of the chamber to the external environment is impossible. The process begins with the absorption of gaseous freon from the evaporator, where it has absorbed the heat of the products.
The gas is then compressed, which leads to a sharp increase in its temperature and pressure. In this state, the refrigerant enters the condenser (usually a grille on the back or sides of the case), where it releases heat to the atmosphere and turns into a liquid. The cycle is completed when liquid freon passes through the throttling device and again enters the evaporator, where it boils at low pressure. Efficiency This process directly affects the cooling rate.
It is important to understand that different types of engines implement this cycle differently. Classic models operate jerkily, turning on at full power and turning off completely when the set temperature is reached. More modern ones inverter systems smoothly regulate the rotation speed, avoiding sudden surges in the load on the electrical network. It is this difference in operating algorithms that determines the service life of parts and the level of energy consumption.
Piston compressors: classics of refrigeration technology
The most common type, which has been installed in household refrigerators for decades, is a piston unit. Its design resembles a miniature internal combustion engine: inside a sealed casing there is a cylinder, a piston and a connecting rod-crank mechanism. When the electric motor shaft rotates, the piston makes a reciprocating motion, building up pressure.
The main advantage of such systems is their time-tested reliability and relatively low production cost. Repairing a piston compressor is often possible, although in practice experts often recommend replacing the entire unit due to the complexity and high cost of the work. However, they have a significant drawback: a high level of vibration and noise, especially at the time of start-up. Piston compressors consume significant current at the time of start, which creates a load on home wiring.
Modern piston models are often equipped with a crankshaft system, which makes their operation smoother compared to older crank-type ones analogues. They can be single or double piston. In two-piston models, one piston compresses the gas, and the second, smaller in diameter, helps create additional pressure, which increases cooling efficiency.
Despite the emergence of new technologies, piston engines remain relevant for the budget and mid-market segments. They do an excellent job of maintaining temperature, but their lifespan is often limited by the number of on and off cycles. Frequent starts lead to wear of mechanical parts and heating of the electric motor windings.
Inverter systems: technologies of the future today
An inverter compressor is a more complex and modern device, which is radically different in its control principle. Unlike classic models, it does not turn off completely after reaching the desired temperature. Instead, it simply reduces power, going into keep-cold mode. The adjustment occurs by changing the engine shaft rotation speed.
This approach allows you to solve several problems at once. Firstly, the noisy and abrupt start, which often frightens users, disappears. Secondly, the absence of constant on-off cycles significantly extends the life of mechanical parts. Thirdly, the temperature in the chambers is maintained with high precision, which has a beneficial effect on the safety of products.
⚠️ Attention: Inverter systems are extremely sensitive to voltage changes in the electrical network. Sudden surges can damage the electronic control board. It is recommended to use high-quality voltage stabilizers or surge protectors to protect expensive equipment.
The energy efficiency of inverter models is much higher. They consume less electricity because they do not waste energy on constant starting currents. That is why refrigerators marked with energy consumption class A++ or A+++ are most often equipped with just such engines. However, the cost of repairing electronics in the event of a breakdown can be significantly higher.
Linear compressors: features of LG technology
Linear compressors, which are actively promoted by LG, deserve special attention, although the technology is also found in other manufacturers. They do not have a crank mechanism, and the piston is driven by electromagnetic forces. This eliminates friction points, which are the main source of wear in piston models.
A linear motor operates on the principle of reciprocating a piston under the influence of a magnetic field. The absence of rotating parts and complex mechanics makes such units very compact and quiet. They take up less space inside the housing, which allows you to increase the useful volume of the refrigeration chamber with the same external dimensions.
The service life of linear compressors is stated by manufacturers to be very high, often up to 20 years or more. They also belong to the inverter type of control, that is, they smoothly regulate the power. However, their repair is practically impossible at home and requires a highly qualified technician, since the design is non-dismountable and high-tech.
It is important to note that linear systems can be sensitive to the quality of the refrigerant and the cleanliness of the system. Moisture or debris entering the circuit can cause rapid valve failure. Therefore, when refueling such refrigerators, compliance with the strictest vacuum technology is required.
Comparison of characteristics: table of differences
To better understand what compressors are installed on refrigerators different price categories, it is convenient to use the comparison table. It will help systematize information and choose the best option for specific operating conditions.
| Characteristics | Piston (Regular) | Inverter | Linear |
|---|---|---|---|
| Operating principle | On/Off | Smooth adjustment | Electromagnetic drive |
| Noise level | High (especially at start) | Low | Minimum |
| Energy consumption | Standard | Low (savings up to 40%) | Very low |
| Service life | 7-10 years | 10-15 years or more | 15-20 years |
| Repair cost | Low | High | Very high |
The table shows that overpaying for modern technologies pays off in the long run due to energy savings and the absence of the need for frequent repairs. However, for a cottage or garage where the refrigerator is used seasonally, the classic piston version is quite suitable.
Why can inverter refrigerators hum?
Sometimes users complain about the hum of inverter models. This is not a breakdown, but a feature of the work. Because the compressor does not turn off, it can produce low-frequency background noise that can be heard in the stillness of the night. Also, a hum can occur at maximum load, for example, immediately after loading a large amount of warm products.
Leading manufacturers and their technologies
The compressor equipment market is dominated by several large players who supply units both for their own equipment and for third-party brands. Understanding who made the engine can say a lot about the quality of the refrigerator as a whole. One of the leaders is the company (formerly Danfoss), whose piston compressors are considered the standard of reliability. They are installed in many European and Russian brands. They are distinguished by survivability and maintainability. Another major player is
One of the leaders is the company Secop (formerly Danfoss), whose piston compressors are considered the standard of reliability. They are installed in many European and Russian brands. They are distinguished by survivability and maintainability. Another major player is Embraco, owned by Nidec, which is famous for its efficient and quiet models.
- 🇰🇷 LG Electronics - a pioneer of linear inverter technologies, provides an extended warranty on its compressors (up to 10-20 years in different regions).
- 🇯🇵 Panasonic and Hitachi - use advanced inverter systems with high precision temperature control.
- 🇮🇹 Aspera (formerly Electrolux) are widely used compressors used in many budget and mid-range refrigerator models.
Chinese manufacturers such as GMCC (owned by Midea) also occupy a huge market share. Their products have become much better in quality in recent years and successfully compete with European analogues in price and reliability. When choosing, you should pay attention not only to the brand of the refrigerator, but also to the markings of the compressor itself.
Fault diagnosis and service life
How to determine that there is something wrong with the compressor? The first sign is often a change in the nature of the job. If the refrigerator starts to turn on more often than usual or, conversely, cannot reach the temperature for a long time, this is a cause for concern. An extraneous knock, clanging or metallic ringing during operation should also alert you.
A common problem with older piston models is “hard start”. The engine hums, tries to start, clicks the relay, but does not start. This may indicate jamming of the piston group or interturn short circuit of the windings. In inverter systems, a malfunction is often reported by the electronics themselves, displaying an error code on the display.
⚠️ Attention: If you hear a loud bang or smell a burning smell, immediately unplug the refrigerator. Operating a faulty compressor can lead to a wiring fire or complete failure of the No Frost system.
The average service life of a compressor is from 10 to 15 years. However, under favorable conditions (stable voltage, clean capacitor, normal load), they last longer. Inverter models are theoretically capable of operating for 20 years or more, but real statistics are still accumulating, since they appeared en masse later.
☑️ Diagnosis of problems with the compressor
Frequently asked questions about compressors (FAQ)
Is it possible to replace a conventional compressor with an inverter one?
Technically this is possible, but it is extremely difficult and expensive. It will be necessary to replace not only the motor itself, but also the control board, and also reprogram the refrigerator controller. Often the cost of such an upgrade exceeds the price of a new refrigerator.
Why does a new refrigerator run loudly in the first hours?
This is normal. When first started, the system enters mode and oil and refrigerant are distributed. Heating of the seals could also have an effect. If the noise does not go away after 24 hours, you should contact the service.
Does tilting the refrigerator during transportation affect the compressor?
Yes, it does critically. If you transport the refrigerator lying down, oil from the compressor may leak into the refrigerant circuit. Turning on such a device without settling (at least 4-8 hours) will lead to water hammer and damage to the piston group.
What is “dry running” of a compressor?
This is the operation of a unit without a sufficient amount of refrigerant (freon). Freon cools the motor during operation. If there is not enough of it (due to a leak), the compressor overheats and burns out. Therefore, in case of leaks, it is important not just to top up the gas, but to find and fix the hole.
Do you need to change the compressor if it is just noisy?
If the noise has become unbearable, but the refrigerator is cold, replacement is possible. However, it is often easier and cheaper to buy a new refrigerator, since the cost of a new high-quality compressor with replacement labor can be up to 50-70% of the price of a new budget model.