What kind of motor is in the refrigerator: a complete guide

When you hear a quiet hum in the kitchen, you know that the refrigerator is working properly. This sound is produced by the main unit - the compressor, which is often mistakenly called simply a motor. Understanding exactly what type of engine is installed in your model is critical when choosing new equipment or diagnosing problems. Modern technologies offer various solutions, from classic piston units to advanced inverter systems.

The choice of device directly affects energy consumptionthe noise level and durability of the entire cooling system. Owners of studio apartments or kitchens combined with living rooms are especially sensitive to the sound background that creates compressor. In addition, the cost of repairing or replacing this unit can be a significant part of the price of a new refrigerator, so knowing the features of the motor helps save the budget.

In this article we will look in detail at what types of motors exist, how they are designed and how they differ from each other. You will find out why some models operate almost silently, while others make a characteristic ticking sound. We will also touch on the topic multi-chamber systemswhere different units can be responsible for cooling different zones.

The principle of operation and the role of the compressor

The main task of the refrigerator motor is to compress the refrigerant and circulate it through a closed circuit circuit of the system. It is compression (compression) that allows the gas to pass into a liquid state in the condenser, giving off heat outside. Without this mechanical effect, freon would not be able to effectively remove heat from the products in the evaporator.

The process begins with the motor sucking in low-pressure gaseous refrigerant. Compression then occurs and the gas is forced under high pressure into a condenser grille, usually located at the back or sides of the housing. In this cycle electric motor is the heart of the entire system, setting the rhythm of work.

There is a misconception that the more powerful the motor, the better it freezes. In fact, it is more important to match the power to the volume of the chambers and the quality of thermal insulation. Excessive power will only lead to excessive consumption of electricity and unnecessary noise, and insufficient power will lead to an inability to maintain the set temperature in hot weather.

Linear (piston) compressors

The most common type of engine that can be found in most refrigerators in the mid-price segment. The principle of their operation is based on the reciprocating movements of the piston. The motor operates in the “start-stop” mode: it turns on at full power, cools the chamber to the set temperature and turns off.

When the temperature inside rises above the set threshold, the thermostat again sends a signal to start. This cycle causes temperature fluctuations which, although within acceptable limits, may affect the preservation of some sensitive products. In addition, constant starts create peak loads the electrical network and mechanical parts of the unit.

Despite the disadvantages, linear motors have a number of advantages. They are cheaper to produce and repairable. Replacing one compressor at a service center is not difficult, and the cost of spare parts remains affordable. Many well-known brands, such as LG and Whirlpool, have been using proven modifications of piston engines for decades.

However, it is worth considering that the moment the engine starts is always accompanied by a characteristic click and hum. If your refrigerator is in a niche or close to a wall, this sound may resonate. Also, frequent switching on reduces the overall service life of the mechanism.

Inverter cooling systems

Technology that has changed the idea of how household appliances work. The inverter motor does not turn off completely after reaching the desired temperature. Instead, it reduces the speed to a minimum, maintaining the cold at a constant temperature. This allows you to avoid sudden surges in voltage and mechanical wear from frequent starts.

The main advantage of such systems is energy efficiency. Electricity consumption is reduced by 20–30% compared to classic models. In addition, operation at low speeds makes the refrigerator almost silent, which is a decisive factor for many buyers.

There are no rubbing parts inside the inverter compressor in the traditional sense, which significantly increases its service life. Manufacturers often provide a warranty on such motors for up to 10–20 years. However, there is also a downside: high sensitivity to voltage surges in the network.

⚠️ Attention: If power surges often occur in your home, be sure to use a stabilizer when connecting a refrigerator with an inverter motor. Repairing the electronics of such systems can be very expensive.

The cost of refrigerators is higher, but it pays off due to energy savings and the absence of the need for frequent repairs. Brands inverter system higher, but it pays for itself due to energy savings and the absence of the need for frequent repairs. Brands Samsung and Bosch are actively introducing these technologies into their flagship lines.

Comparative table of characteristics

To make it easier for you to decide which motor is best suited for your conditions, we have prepared a comparison table. It will help you weigh the pros and cons before purchasing new equipment or replacing an old unit.

The table shows that technological progress is shifting the balance towards inverter solutions. However, for a cottage or garage where equipment works seasonally, it may not make sense to overpay for complex systems. In such cases, reliable piston unit will become a more rational choice.

Two-compressor refrigerators

Models in which two independent motors are installed deserve special attention. Typically, one compressor serves the freezer compartment, and the second one serves the refrigerator compartment. This allows you to independently regulate the temperature and turn off one of the chambers, for example, during defrosting or a long absence of the owners.

The presence of two motors increases the reliability of the system. If one unit fails, the second will continue to work, keeping the products intact in its area. This is especially true for large family refrigerators and Side-by-Side models, where the volume of chambers is large.

However, this design has its own characteristics. Firstly, there is an increased noise level, since two sound sources are working. Secondly, energy consumption may be higher, although modern dual-compressor models are often equipped with efficient inverter motors that eliminate this disadvantage.

Visually the presence of two motors can be determined by two capacitor arrays or by the characteristic sound of operation when they turn on both units at the same time. Brands Liebherr i Electrolux often use this scheme in premium series.

How to determine the type of motor without opening it

It is often necessary to find out which motor is installed in your refrigerator without calling a technician. The easiest way is to study the technical data sheet or sticker on the back of the device. The compressor model and its type are indicated there.

If the documents are lost, pay attention to the behavior of the refrigerator. If it makes periodic clicks and buzzes at intervals (works for 10 minutes, is silent for 20) - this is classic linear compressor. If the sound is monotonous, quiet and the refrigerator works almost constantly, without turning off for hours, you have a inverter system.

You can also estimate the level of energy consumption by the efficiency class sticker. Models of class A and below are almost always equipped with conventional motors. Classes A+, A++ and A+++ highly likely indicate the presence of inverter technology or a linear inverter motor.

In some cases, information about the type of compressor is printed directly on the unit itself, which is visible when the lower rear cover is removed. But this should only be done when the device is disconnected from the network and observing safety measures.

Frequent faults and diagnostics

Even the most reliable motor can fail. Common problems include burnout of the electric motor winding, jamming of the piston group, or freon leakage, which is often mistaken for a motor failure. If the refrigerator hums but does not cool, this is an alarming signal.

Another common problem is the failure of the start relay. This small device is responsible for starting the motor. If the relay is faulty, the compressor may hum, jerk, but not start, or blow out the automatic fuse in the panel. Replacing the relay is a simple and inexpensive procedure.

Overheating of the motor is also dangerous. If the refrigerator is located close to the wall or in a niche without ventilation, the heat is not removed and compressor works with overload. This shortens the life of the oil and mechanical parts.

⚠️ Warning: Never attempt to open the sealed compressor housing or change the oil inside it yourself. This requires special equipment and skills, and at home it often leads to complete breakdown of the unit.

Modern diagnostic systems often display an error code on the refrigerator display. For example, this may be a code, and this may be flashing indicators. Deciphering the code will help you understand whether the problem lies in the motor itself or in the control system. Samsung this could be the code 22C, and LG - flashing indicators. Deciphering the code will help you understand whether the problem lies in the motor itself or in the control system.

FAQ: Frequently asked questions