The heart of any modern refrigerator is its compressor. It is this unit that determines how quietly the equipment will operate, how much electricity it will consume, and how long it will last without costly repairs. In everyday life, you can often hear how this mechanism is mistakenly called a “motor” or “engine,” although technically it is a pump that creates refrigerant pressure in the system.
Understanding this what types of compressors are there in a refrigeratoris necessary not only for engineers, but also for the average consumer when choosing new equipment. The market offers many options: from classic piston units to modern inverter and linear models. Each of them has its own design features, advantages and disadvantages.
In this article we will analyze in detail the design of various types of compressors, compare their characteristics and help you make a choice based on real technical data, and not just on the marketing promises of manufacturers.
Principle of operation and purpose compressor
The main task of the compressor is to compress the refrigerant and force it to circulate through the closed circuit of the refrigeration system. Gaseous freon, leaving the evaporator, is sucked in by the compressor, compressed and sent under high pressure to the condenser, where it cools and turns into liquid. This cycle is repeated continuously, ensuring that the temperature inside the chambers is maintained at a low temperature.
The design of the device can vary significantly. In classic models an electric motor is used that drives the pistons or rotor. Modern solutions often integrate the motor and pump into a single sealed unit, which reduces vibration and noise levels. It is important to understand that it is the compressor that consumes up to 90% of all the electricity that the refrigerator uses.
The reliability of this unit is critically important, since replacing it is a complex and expensive process that requires evacuation of the system and charging with refrigerant. Therefore, in the event of a breakdown, the question of whether it is advisable to repair or purchase new equipment is often considered.
⚠️ Attention: Independent disassembly or attempt to repair a hermetic compressor without specialized equipment and skills in working with freon is prohibited. This can lead to gas leakage, damage to the cooling system and even an explosion of refrigerant vapor.
The service life of the compressor directly depends on the quality of the build, operating conditions and the type of compression technology used. Modern manufacturers strive to minimize the number of rubbing parts in order to increase service life.
Piston compressors: classics of refrigeration technology
The most common type, with which most users are familiar, is piston compressor. The principle of its operation is similar to the operation of an internal combustion engine, only without the combustion process. Inside the sealed casing there is an electric motor, which, through a crank mechanism, drives one or more pistons.
The pistons move back and forth, alternately sucking in the refrigerant and compressing it. Such units are divided into crank and linear units (which we will talk about later). Crank models can have different layouts: vertical or horizontal. Vertical options are more often found in household refrigerators due to their compactness.
The main advantage of piston models is their time-tested reliability and relatively low production cost. They are less sensitive to voltage changes in the network compared to some complex electronic analogues. However, they also have significant disadvantages.
- 🔊 High noise level: due to the reciprocating movements of the piston and the operation of the valves, a characteristic hum and vibration occurs.
- 📉 Low energy efficiency: classic models consume more electricity when entering the mode.
- ⚙️ Wear of mechanical parts: the presence of many moving parts (connecting rod, piston, rings) leads to gradual wear and loss of performance.
Despite the disadvantages, piston compressors remain popular in the budget segment and in middle-class models. Manufacturers are constantly improving the design, introducing noise reduction systems and improving the aerodynamics of valves.
Rotary and scroll compressors
In search of an alternative to noisy piston units, engineers have developed rotary and scroll compressors. In rotary models, gas compression occurs due to the rotation of the rotor in an eccentric cylinder. The rotor blades are pressed against the cylinder walls under the action of centrifugal force, dividing the space into chambers of variable volume.
Scroll compressors, often used in industrial installations and expensive models of household appliances, consist of two spirals: movable and fixed. The refrigerant is compressed in pockets formed between the turns of the spirals during their relative motion. This ensures a very smooth compression process without pressure pulsations.
The main advantage of such solutions is minimum level of vibration and noise. The absence of reciprocating movements makes the operation of the equipment almost silent. In addition, scroll compressors have high efficiency and compact dimensions.
However, the production cost of such units is much higher. Complex geometry of parts requires high precision processing. Repairing scroll compressors in a domestic environment is practically impossible, and if they break down, a complete replacement of the unit is required.
Inverter compressors: technology of the future
Today inverter compressor is considered one of the most advanced solutions in the refrigeration industry. Unlike traditional models, which operate on an “on-off” principle, the inverter motor works constantly, but with variable rotation speed.
When you have just loaded food into a warm refrigerator, the compressor works at maximum speed to quickly cool the chamber. As soon as the set temperature is reached, it does not turn off completely, but reduces the speed to a minimum, only maintaining the cold. This allows you to avoid constant starting currents, which are most harmful to the electric motor.
The advantages of inverter technology are obvious:
- 🔇 Silence: the absence of relay clicks and sudden starts makes the operation of the refrigerator almost imperceptible.
- 💰 Energy saving: electricity consumption is reduced by 20-30% compared to classic models.
- 🛡️ Durability: the absence of frequent on/off cycles reduces wear on mechanical parts.
- 🌡️ Temperature stability: products are stored in ideal conditions without temperature surges, characteristic of the operation of a conventional compressor.
However, inverter models also have their own characteristics. They are more sensitive to voltage changes in the electrical network. If the voltage in your home often fluctuates or there are blackouts, it is recommended to use a stabilizer.
The cost of refrigerators with an inverter compressor is higher, but the difference in price is usually recouped by savings on electricity and no need for repairs for many years.
Linear compressors: direct drive
Separate deserves attention linear compressor, which is often confused with inverter, although these are different technologies. Such units are actively promoted by LG. A linear compressor does not have a crank mechanism. The piston is driven by electromagnetic forces, making reciprocating movements in a straight line (hence the name).
The absence of rotating parts and complex mechanical gears makes the design very simple and reliable. Friction in the system is minimized, which has a positive effect on energy consumption and noise levels. Linear compressors can also operate in inverter mode, smoothly regulating power.
Key features of linear models:
- Minimum number of friction points, which reduces wear.
- High rate of cooling of products upon first start-up.
- Compact dimensions, allowing you to increase the useful volume of the refrigerator.
However, like any complex equipment, linear compressors have their weak points. The main element susceptible to breakdowns is the electronic control unit, which regulates the operation of the electromagnet. If the compressor itself fails, replacing it will cost more than a regular piston compressor.
The truth about the 10-year warranty
Many manufacturers give a 10-year warranty on the compressor, but this does not mean free replacement of the entire refrigerator. The warranty often extends only to the unit itself (motor), and work on diagnostics, dismantling, installation and refilling with freon is paid by the owner.
Single-compressor and two-compressor systems
When choosing a refrigerator, it is important to pay attention not only to the type of motor, but also to their number. Single-compressor systems serve both the refrigeration and freezer compartments at once. In such models, one compressor drives the refrigerant through two circuits (or one at a time with separation of flows), which is a more economical and simpler solution.
In two-compressor models, each chamber is responsible for its own independent unit. This allows you to set different temperatures in each compartment independently of each other. For example, you can turn off the refrigerator compartment, leaving the freezer running, which is convenient if the owners are absent for a long time.
Comparison of systems:
| Characteristics | One compressor | Two compressors |
|---|---|---|
| Energy consumption | Lower (one motor) | Higher (two motors) |
| Noise level | One noise source | Two sources (but can work on queues) |
| Independence of cameras | Dependent (often) | Completely independent |
| Repair cost | Cheaper | More expensive (two units) |
| Defrosting | More difficult (you need to defrost everything) | Can be defrosted separately |
Two-compressor models are more often found in large-volume and premium refrigerators. For a small family or studio apartment, most often a high-quality single-compressor unit with a No Frost system is sufficient.
⚠️ Attention: In two-compressor models, the load on the electrical network is distributed differently. Make sure that the wiring at the installation site can withstand the simultaneous (albeit short-term) launch of two powerful consumers, unless the electronics separate their start in time.
☑️ Check before purchasing
Comparison of characteristics and reliability
When choosing between different types of compressors, you should be guided by specific needs. If your priority is silence and economy, then inverter technology they are the uncontested leader. They provide comfort and stability of food storage.
If the budget is limited and voltage drops in the network are a common occurrence, then a classic piston compressor from proven brands (for example, Secop, Danfoss, Atlant) will become a reliable “workhorse”. They are easier to repair, and spare parts for them are easier to find.
The reliability of any compressor also depends on the quality of the refrigerant and oil used in the system. Modern environmentally friendly freons (R600a isobutane) require special attention to the tightness and cleanliness of the system. R600a is explosive in high concentrations, so repairs of such refrigerators must be carried out in compliance with strict safety measures.
The service life of modern compressors is on average 10-15 years. However, the actual resource depends on operating conditions: room temperature, frequency of door opening, food loading and power supply stability.
Frequently asked questions (FAQ)
How to understand that the refrigerator compressor is faulty?
The main signs of failure: the refrigerator has stopped freezing, the compressor is humming, but does not start (a clicking sound is heard), the motor is running continuously without stopping, or the motor is excessively hot to the touch. Also a sign may be the knocking out of plugs or circuit breakers in the panel when turned on.
Is it possible to replace a conventional compressor with an inverter one?
Theoretically it is possible, but it is technically very difficult and economically impractical. It will be necessary to replace the control board, resolder the electrical circuits, and reconfigure the system. It’s easier and cheaper to buy a new refrigerator with the right type of compressor.
Why does the compressor get very hot?
Heating up to 60-80 degrees for a working compressor is the norm. However, if it is heated to the point that it is impossible to touch it, this may indicate a clogged capillary tube, a freon leak, or a malfunction of the motor itself (interturn short circuit).
Which brand of compressors is considered the best?
The company Secop (formerly Danfoss)is considered one of the market leaders. producing reliable piston compressors. Among inverter systems, the developments of LG and Samsung are highly valued. Chinese brands (GMCC, Jiaxipera) also occupy a large market share and show good quality in the middle segment.
Does the type of compressor affect the noise level?
Yes, it does significantly. Inverter and linear compressors are much quieter than classic piston compressors. Also, the noise level depends on the quality of the sound insulation of the case and the method of installation of the refrigerator (whether it stands level or does not touch the walls of the furniture).