A Refrigerator has been the most useful and essential appliance for the household. We cannot even store our food without a refrigerator at our home. To operate and use a refrigerator efficiently, you must know how does a refrigerator works.
On Which Principle does a Refrigerator Work?
The working principle of a refrigerator is based on vapor compression refrigeration cycle. It involves the removal of heat from the refrigerated space to the surrounding. The refrigeration cycle involves four components to work-
- Expansion valve
A refrigerator works in the following step-by-step process:
Step-1: The working process starts with the compressor. In this cycle, a circulating fluid, called refrigerant, enters the compressor in the vapor state. Inside it, the refrigerant gets superheated.
Step-2: The superheated vapor travels through the condenser and dissipates the superheat outside the refrigerator. So, the room you keep in the refrigerator gets heated, and when the vapor leaves the condenser, it becomes liquid.
Step-3: Next, the liquid refrigerant passes through an expansion valve. Here the pressure of the refrigerant decreases.
Step-4: Ultimately, it passes through the evaporator, where the cold refrigerant cools the warm air down. For this reason, the refrigerator chamber gets cold.
When the refrigerant leaves the evaporator, it gets to the vapor state again, and the vapor then passes through the compressor again and completes the cycle. This is how a refrigerator works. Home appliances like air conditioners also work on the same refrigeration cycle.
Also read: Best Refrigerators in India
Components of refrigeration cycle – detailed explanation
A refrigerator has two storage compartments – One for items requiring refrigeration and other frozen items. These compartments are surrounded by a series of heat-exchanging pipes. These are hidden in the walls of the refrigerator. At the bottom, the compressor is placed. Read the following details of Parts of the Refrigerator and the Function of each one.
A compressor is a device that works mechanically to increase the pressure of a gas by reducing its volume. It is very similar to a motor. However, a motor cannot handle multiple phases of a substance together. Whereas, a compressor can handle liquid and gaseous phases together.
There are many types of compressors available- rotary, reciprocating, inverter, non-inverter, dual-inverter, etc. Nowadays, inverter compressors are emerging rapidly in the market as they are most efficient in minimizing power consumption.
Learn: Rotary vs. Reciprocating Compressors
The condenser is an essential component of a refrigerator as it condenses the heated refrigerant into liquid form. Without it, a fridge won’t work. It consists of coiled tubes made of copper with external fins and is located at the backside of the refrigerator. With such a condenser structure, the heat dissipation gets the most efficient.
3. Expansion/ Throttle valve
The Expansion valve controls the flow of refrigerant. The main objective of using such a valve is to decrease the pressure of the refrigerant before directing it to the evaporator. This is a small device that is very sensitive to the change in temperature of the refrigerant.
A refrigerator cools because the heat inside the fridge gets transferred to the surroundings. The evaporator works precisely for this cause, and it consists of finned tubes with high thermal conductivity to maximize heat transfer. A fan blows out the heated air outside, and the refrigerant turns into vapor and flows towards the compressor.
What Contributes to the smooth working of the refrigerator?
- Temperature Controlling Device
We can see from the Refrigeration Cycle that heat is taken away from the refrigerator, and eventually, it cools down the working space.
However, we need control of the temperature to decide how cool the refrigerator should be. For this purpose, a temperature control device or thermostat is built with a fridge. The sensor of the thermostat is connected to the evaporator. When the refrigerator reaches the set temperature, the electrical connection to the compressor is cut down.
As a result, the cooling system stops. When the temperature rises again, the compressor automatically starts up.
- Inbuilt Voltage Stabilizer
Fluctuating voltage may harm the refrigerator. The get a steady voltage, a voltage stabilizer is needed. Some refrigerators have an inbuilt stabilizer, and your refrigerator might not have an inbuilt stabilizer. In this case, you should buy a separate stabilizer to protect your fridge.
- Automatic Defrosting System
The defrosting system is an essential integral part of a refrigerator. There are two types of defrosting- Manual & Automatic, and most of the advanced Refrigerators are built with an Auto Defrosting System.
However, Refrigerators with a lower budget might have a manual defrosting system. It would be best to buy a refrigerator with an Auto Defrosting System to ease daily life. The defrosting system in a refrigerator is a crucial factor in improving refrigeration quality.
- Anti Fungal Gasket on Door
The refrigerator you choose should have an Antibacterial gasket built on the door opening. This type of gasket can be removed, cleaned, and easily fitted on the door again. It prevents fungus development so that the fridge can give you healthier food every time.
- Shelves and Ice Trays
The shelves and Ice trays are inbuilt. With an increase in the working volume inside the fridge, the number of shelves increases. With more shelves, you have more space inside the refrigerator. Similarly, the Ice trays also play a critical role when the concern is a freezer.
- Water and Ice Dispenser
For most of the side-by-side refrigerators, Water Trays are provided. Double door and side by side refrigerators have ice dispensers that ease out the handling of the freezer.
Apart from these essential parts for smooth working, there are a few more, which you might want to have with the refrigerator. The door Alarm, well-positioned Light, Digital Display are built with a good quality refrigerator like Samsung 253 L 4 Star Frost Free Double Door Refrigerator.
Brands like Samsung manufactures 5 in 1 convertible refrigerators that can handle the fridge and freezer separately with different control modes suitable for various operations.
Frequently Asked Questions
A refrigerator works on the refrigeration cycle. In this cycle, heat is taken away from the working volume of a refrigerator by an evaporating substance called refrigerant with the help of a compressor, evaporator, condenser, and throttle/ expansion valve.
The main parts are a compressor, condenser, evaporator, and throttle/ expansion valve. Apart from these, a temperature controlling device, voltage stabilizer (optional), defrosting system, water & ice dispensers (optional) are installed with most refrigerators.
There are so many good products for a refrigerator by some best brands that are excellent in performance and design. Among them, LG, Samsung, Whirlpool are the most reliable.
Apart from the significant advantages, refrigerators have some disadvantages that you should be aware of. They are unfriendly to the environment. Many refrigerants like Freon are responsible for increasing holes in the ozone layer allowing ultraviolet radiation and creating other harmful effects in the earth’s atmosphere. If not disposed of properly, a refrigerator can be dangerous for the environment.
Working method of refrigerator: Bottom Line
You should know a refrigerator’s working principle whether you already have one or plan to buy a new fridge. As described above, this is the basic principle of a refrigerator, and you have learned how a refrigerator works. Knowing the essential parts, operating, and handling might have been easier for you now.
Here is an excellent video by Learn Engineering on the basic working principle of a refrigerator.