Understanding what the parts of a refrigerator are called is critical not only for repair engineers, but also for any owner of household appliances. When a unit begins to make noise, stops freezing, or leaks, the ability to accurately identify the problem by the name of the unit significantly speeds up the search for a solution. In technical documentation and when ordering spare parts, specific terms are used that can confuse an untrained person.
In this article we will analyze the anatomy of a modern refrigeration unit, from the outer shell to the smallest elements of the cooling system. You will find out how evaporator is different from condenser, where it is capillary tube and why it is needed receiver. This knowledge will help you correctly formulate a request to the service department or independently carry out an initial diagnosis of the malfunction.
Modern refrigerators, be it then classical Atlant or complex multi-chamber Liebherrare based on common principles of thermodynamics. However, the design of the nodes can vary significantly. We will consider both the general scheme of operation and the specific names of the parts so that you can navigate the structure of any model.
Main components of the refrigeration unit
The heart of any refrigerator is the compressor-condenser unit. This is where the key processes of compression and cooling of the refrigerant take place. Many people mistakenly believe that cold is produced magically, but in fact it is the result of complex circulation of freon in a closed circuit, where each part has its own strictly defined name and function.
The first and most important element, which is often called the "motor", is compressor. This is a sealed electromechanical pump that creates the pressure necessary to move the refrigerant through the system. Without its proper operation, freon circulation is impossible, and the cold will not enter the chambers. In modern models there are both classic piston and quieter inverter compressors.
Immediately after leaving the compressor, hot gas under high pressure enters condenser. Externally, it is a lattice of tubes, most often located on the back wall of the device. The main task of this unit is to release heat to the environment. Passing through the turns of the condenser, freon cools and passes from a gaseous state to a liquid, remaining under high pressure.
⚠️ Attention: Touching a working condenser (rear grille) while the compressor is operating is dangerous - the metal temperature can reach 80-90 degrees Celsius, which fraught with burns.
Next, the liquid refrigerant passes through filter-drierwhich removes excess moisture and mechanical impurities from the system. This is a critical element in preventing ice plugs from forming in narrow channels. After the filter, the pressure drops sharply when freon enters the capillary tube, and it begins to actively evaporate, absorbing heat from the internal space of the chambers.
Internal structure of the refrigerator and freezer compartments
Looking inside the refrigerator, the user sees a space organized using various plastic and metal elements. Correctly naming these parts is essential when ordering a replacement for a broken shelf or cracked drawer. The design of the internal volume directly affects the ergonomics and distribution of cold.
The walls of the chambers are often equipped with shades or channels through which cold air is supplied from the evaporator. In No Frost systems, a radiator is hidden behind the rear panel, which directly cools the air. A fan located nearby drives this air through the channels, ensuring uniform temperature throughout the entire volume. evaporator - a radiator that directly cools the air. A nearby fan drives this air through the channels, ensuring uniform temperature throughout the entire volume.
For storing products, balcony shelves (on the door) and main glass or lattice shelves are used. The door is sealed using magnetic seal (rubber cuff). If the seal loses elasticity or breaks, warm air enters the chamber, which leads to the formation of ice and increased load on the compressor.
- 🧊 Evaporator - heat exchanger where freon boils and takes heat from chambers.
- 💨 Fan —provides air circulation in systems with forced airflow.
- 🚪 Seal —rubber cuff with a magnetic insert to seal the door.
- 💡 Lighting shade —a protective cap for a lamp or LED module.
It is important to distinguish between the types of internal coating. Budget models use enamel, while more expensive ones use an antibacterial coating based on silver ions or durable plastic. Damage to the internal coating, especially in the freezer compartment, can lead to corrosion of the metal and failure of the entire chamber.
Defrost and temperature control system
Modern refrigerators do not require manual defrosting thanks to automatic defrosting systems. In units with No Frost or Low Frost technology, a key role is played by the The defrost heating element (tubular electric heater). It turns on periodically to melt the frost accumulated on the evaporator.
The defrosting process is controlled thermostat (or a defrost sensor). When enough ice accumulates on the evaporator or the specified compressor operating time passes, the thermostat opens the compressor circuit and closes the heating element circuit. After the ice has melted and the sensor has recorded a positive temperature, the system starts the cooling cycle again.
Responsible for the overall coordination of the operation of all nodes electronic control module. This is the “brain” of the refrigerator, which reads the temperature sensors in the chambers and on the evaporator, controls the fan, compressor and valves. Failure of even one small sensor can lead to improper operation of the entire unit.
On the evaporator
| Part | Function | Location | Frequent malfunction |
|---|---|---|---|
| Defrost heating element | Heating and melting of ice | Under the evaporator | Burning threads |
| Thermostat | Defrost temperature control | Contact sticking | |
| Temperature sensor | Cold data transmission | Inside the camera | Resistance reading failure |
| Control module | Signal processing | Top or back | Relay failure |
It is worth noting that the number of sensors may vary in different models. In simple systems there is one thermostat, in complex multi-chamber Bosch or Siemens there can be three or more of them: for the refrigerator, freezer and freshness zone.
Refrigerant and piping system
The basis of circulation is refrigerant (freon). In older models, it was used R12, which is now prohibited due to its harm to the ozone layer. Modern refrigerators run on R600a (isobutane) or R134a. These substances are colorless and odorless, but isobutane (R600a) is explosivewhich requires special care during repairs and prohibiting the use of open fire near the pipes.
The pipelines are made made of copper or steel. Occupies a special place capillary tube —a very thin copper pipeline (less than 1 mm in diameter) that serves as a choke. It is in it that a sharp drop in refrigerant pressure occurs before entering the evaporator, which causes its active boiling and cooling.
Another important element is receiver (or battery). This is a container installed at the outlet of the evaporator in front of the compressor. Its task is to ensure that only freon gas enters the compressor. The ingress of liquid fraction ("water hammer") can instantly destroy the compressor valves.
Why can't you just add freon?
Adding freon without evacuating the system and replacing the filter-drier will lead to a quick breakdown of the compressor. There should be no air or moisture in the system, and the amount of refrigerant should be strictly gram by gram by weight indicated on the nameplate.
Electrical circuit and starting equipment
A special device is used to start the compressor engine - start-protection relay. It consists of a starting winding and a thermal relay. When starting, the relay supplies increased current to move the motor rotor and then turns off the starting winding. The thermal relay opens the circuit if the current exceeds the norm, protecting the motor from combustion.
In inverter models there is no classic relay. Its functions are performed inverter unit, which smoothly changes the rotation speed of the compressor shaft. This saves energy and reduces noise, but makes diagnostics more complex, as it requires special equipment to check signals.
The electrical circuit also includes thermostat a (mechanical) or electronic sensor that opens the compressor power circuit when the set temperature is reached. In old models it was a knob with numbers, in new ones it was part of an electronic control board.
- 🔌 Start relay - starts the motor and protects against overloads.
- ⚡ Inverter - converts the current for smooth operation motor.
- 🌡️ Thermoregulator —turns the refrigerator on and off based on temperature.
⚠️ Attention: Independent replacement of the starting relay is possible, but only when the device is completely disconnected from the network. Residual voltage in capacitors can be dangerous.
☑️ Diagnostics before calling a technician
External elements and mounting details
Do not forget about the external components that provide stability, protection and aesthetics. Support rollers or adjustable legs allow you to set refrigerator by level. This is critical for the proper operation of the doors and compressor - misalignment causes vibration and noise.
The rear wall is closed compressor casing (crankcase), which protects from dust and accidental touches. It is often located at the bottom tub for collecting condensate. The water generated during defrosting flows through the drainage tube into this bath and evaporates from the heat of the running motor.
The doors are attached to the housing using hinges. In models with reversible doors, the hinges have a symmetrical design that allows you to change the opening direction. Also on the doors there may be butyl inserts (transparent covers on the shelves) that prevent the products from drying out.
Understanding the structure of the refrigerator allows you not only to save on diagnostics, but also to extend life technology. Regular cleaning of the condenser from dust, checking the integrity of the seal and correct placement of products is the key to the long service of all the components described above.
What is a capillary tube and why does it often clog?
The capillary tube is the narrowest section of the refrigeration circuit. This is where the pressure difference is created. It clogs most often due to oil breakdown products or moisture if the vacuum in the system has been broken. The moisture freezes into ice and blocks the flow of freon.
Is it possible to replace the evaporator yourself?
Replacing the evaporator is a complex process that requires opening the housing (in foamed models), soldering copper tubes, evacuating the system and refilling the exact amount of freon. It is impossible to do this efficiently without special equipment and skills.
Why do you need a filter drier?
The filter drier contains zeolite, which absorbs moisture from the system. Moisture in the circuit with freon is dangerous because it can freeze in the capillary, blocking the circulation, or react with the oil, forming an acid that corrodes the tubes from the inside.
Why does the compressor hum?
The hum can be caused by vibration of the tubes that touch the housing, wear of the motor bearings, or because the refrigerator is not level. If a new refrigerator is humming, this may be a feature of the compressor, but a loud metallic clang indicates a breakdown.