The refrigerator is an integral part of the modern kitchen, keeping food fresh for a long time. Many users take this unit for granted, thinking about its internal structure only when breakdowns occur. However, understanding how equipment works helps to extend its service life and avoid costly repairs.
The central element of any refrigeration system, be it a classic single-chamber unit or a modern one Side-by-Sideis the compressor. It is this unit that is responsible for circulating the refrigerant and creating the necessary pressure in the system. Without its proper operation, the conversion of electrical energy into cold becomes impossible, and food begins to deteriorate.
In this article we will analyze in detail What is a compressor for? the refrigerator, consider its structure, main types and signs indicating the need for diagnostics. Knowing these nuances will allow you to quickly respond to changes in the operation of a household appliance.
The main function of a compressor in a cooling system
The main task of this unit is to create the pressure difference necessary for the circulation of refrigerant in a closed circuit. The compressor sucks in gaseous freon, which has already given up its heat in the evaporator, and compresses it. As a result of this process, the gas is heated and sent under high pressure to the condenser.
After passing through the condenser, where the refrigerant cools and turns into a liquid state, it enters the capillary tube. Here the pressure drops sharply, and the liquid enters the evaporator, where it boils, actively absorbing heat from the refrigerator chambers. This cycle is repeated continuously until the temperature inside reaches the set values.
An analogy can be drawn with the human heart: if the compressor stops, the “blood” (freon) stops circulating, and the body (refrigerator) stops functioning. Modern models, such as Liebherr or Bosch, use complex control systems to optimize this process.
It is important to understand that the efficiency of the entire system directly depends on the performance of this unit. If compressor power is insufficient for the volume of the chambers, the equipment will work for wear, trying to compensate for the lack of cold.
Design and principle of operation of the motor
Structurally, the compressor is a sealed block, inside which there is an electric motor and mechanical part (crank mechanism). All these elements are immersed in oil, which provides lubrication of rubbing parts and additional sealing. The housing is usually made of durable steel and painted black for better heat dissipation.
When voltage is applied to the engine windings, the rotor begins to rotate, driving the crankshaft. Pistons mounted on connecting rods perform reciprocating movements, building up pressure. There are nozzles on the housing: one for sucking in cold gas, the other for pumping hot gas.
Why is the compressor housing hot?
During the process of gas compression, the temperature inside the cylinder increases significantly. Part of this heat is transferred to the case, so heating up to 60-80 degrees Celsius is the norm and not a sign of failure.
A start-up relay is used to protect against overheating and voltage surges. It opens the circuit if the current exceeds the permissible limits or if the engine cannot start. This prevents combustion of the windings and failure of the expensive unit.
- 🔧 Sealed housing —protects internal mechanisms from dust and moisture, and also prevents freon leakage.
- ⚙️ Crank mechanism —converts the rotational movement of the shaft into the translational movement of the piston.
- 🌡️ Oil cooling system —provides lubrication of bearings and heat removal from rubbing pairs.
It is worth noting that in inverter models the operating principle is distinguished by the absence of a strict connection to the network frequency. The electronics smoothly regulate the shaft rotation speed, which avoids constant switching on and off.
Types of compressors: linear, inverter and piston
There are several main types of compressors on the household appliances market, each of which has its own characteristics. The classic piston unit works on the principle of reciprocating piston movement. It is reliable, repairable, but creates a certain level of noise and vibration.
Inverter models, which are actively promoted by brands like Samsung and LG, operate continuously, changing only the power. This allows you to maintain the temperature with high accuracy and save energy. However, such systems are sensitive to voltage changes in the network.
Linear compressors, often called magnetic, use electromagnetic forces to move the piston. They have no rubbing parts in the traditional sense, making them quiet and durable. However, their repair is often impossible; a complete replacement of the unit is required.
Comparing the characteristics of various types will help to better understand their differences:
| Characteristics | Piston | Inverter | Linear |
|---|---|---|---|
| Noise level | Medium / High | Low | Very low |
| Energy efficiency | Standard | High (class A++) | Maximum |
| Service life | 7-10 years | 10-15 years | Up to 20 years |
| Repair cost | Low | High | Replacement unit |
The choice of compressor type affects not only the price of the refrigerator, but also for the comfort of its use. If silence is important to you, it is worth considering more modern options, despite their cost.
Symptoms of malfunction and diagnostic methods
You can determine what refrigerator compressor requires attention using a number of indirect signs. The first alarm bell is often a change in the sound of the unit. The appearance of knocking, grinding or excessively loud humming indicates wear and tear on the mechanical parts.
Another important symptom is the inability of the refrigerator to reach temperature. If the food begins to thaw, and the motor runs without interruption or, conversely, does not turn on at all, the problem may lie in the electrical part or loss of performance.
☑️ Diagnosis of cooling problems
It is also worth paying attention to the temperature of the compressor housing itself. If it is hot to such an extent that it is impossible to touch it, or, conversely, remains cold when the engine is running, these are signs of a serious malfunction.
- 🔊 Extraordinary sounds - knocking, clanging or whistling during operation.
- 🔥 Overheating - the compressor housing is hotter than usual (above 90 degrees).
- ❄️ Lack of cold —when the engine is running, the chambers are warm.
⚠️ Attention: If you smell burning or see sparking in the engine compartment area, immediately unplug the refrigerator. Continued operation may result in a fire.
Accurate diagnostics often require special equipment, such as pressure gauges to check system pressure and a tester to measure winding resistance. Independent disassembly of the hermetic unit without skills and tools is impractical.
The influence of operating conditions on service life
The service life of a compressor directly depends on the conditions under which it operates. Frequent switching on and off, caused by the door not being tightly closed or the temperature being set too low, leads to accelerated wear of the starting equipment and mechanics.
The location of the refrigerator also plays a role. If the unit is located close to a wall or in a niche without gaps for ventilation, the heat transfer of the condenser deteriorates. The compressor is forced to work longer and harder to compensate for overheating of the system.
The quality of the power supply is another critical factor. Voltage surges can damage the motor windings or damage the control electronics. The use of a voltage stabilizer is recommended in houses with old wiring.
Regular defrosting (for systems No Frost this is less important, but drainage control is important) helps maintain heat transfer efficiency. An evaporator clogged with frost forces the compressor to operate under increased load.
Replacement and repair: what the owner needs to know
If the compressor fails, the owner is faced with the question: repair or replace? In most cases, especially when the valves are broken or the piston group is jammed, repairs are not economically feasible. Manufacturers often offer replacement of the entire assembly.
The replacement process requires evacuation of the system, refilling freon and replacing the filter-drier. These are complex technical manipulations that cannot be performed efficiently without professional equipment. Attempts at independent intervention often lead to complete breakdown of the refrigerator.
⚠️ Attention: Freon used in modern refrigerators can be a fire hazard (for example, isobutane). Compressor replacement work should only be carried out by certified specialists in a well-ventilated area.
When choosing a new compressor, it is important to consider not only the overall dimensions, but also the cooling capacity, type of refrigerant and electrical characteristics. An incorrectly selected analogue may not provide the required performance or quickly fail.
Is it possible to install a more powerful compressor?
Theoretically, yes, but this will upset the balance of the system. The condenser and evaporator may not be able to cope with the increased flow of refrigerant, which will lead to water hammer and breakdown.
The cost of the replacement service consists of the price of the unit itself and the work of the technician. In some cases, especially for older models, this amount can be a significant part of the cost of a new refrigerator, which makes the purchase of new equipment a more rational decision.
Frequently asked questions (FAQ)
Why does the refrigerator compressor get very hot?
Heating of the compressor is a natural process, since gas is released when compressed warm. However, if the housing is red-hot or smoke is coming from it, this may indicate an interturn short circuit, a malfunction of the thermostat, or a clogged capillary system.
How long does a compressor last on average?
The average service life of a modern compressor is from 10 to 15 years with proper operation. Inverter models can operate for up to 20 years or more due to the absence of constant start and stop cycles.
Is it possible to restore a frozen compressor?
If the compressor does not start because the refrigerator was in the cold, it cannot be turned on immediately. It is necessary to let it warm up at room temperature for 24 hours so that the oil regains its properties. After this, a successful start-up is possible.
Is it normal for the compressor to hum?
A uniform hum or vibration during operation is normal for piston compressors. A sharp metal knock, a creaking or a change in the tone of the sound, as well as a hum that does not stop after stopping the engine should alert you.