A refrigerator is an essential part of every home. It helps to keep vegetables fresh, preserve food, and make the beverages cold. Refrigeration is the most popular food storage technique in the world, which works by keeping the temperature low and thereby, preventing bacterial reproduction and growth.

But do you know how does it lower the temperature as per your settings? It is the refrigerant gas that is responsible for lowering the temperature. If you are wondering how this is even possible, here are all the details you should know about refrigerant gas.

What Is Refrigerant Gas and How It Works?

Refrigerant gas is a chemical gas with a very low evaporation point due to which it turns into liquid form quickly. Therefore, it evaporates faster due to heat present in the system initially, and then it condenses to make the surrounding air chilled-out. This gas undergoes evaporation and condensation process in a repetitive cycle to absorb all the heat in the refrigerator, and naturally, the temperature inside the refrigerator goes low.

The refrigerant gas goes through the compressor of a refrigerator. The compressor raises the pressure on the gas, and gas gets hot due to high pressure. This hot gas is pushed out to the coils located on the outside of the refrigerator. These coils are cold, and when hot gas passes through them, it releases the heat and turns into liquid form.

This liquid refrigerant flows into the coils inside the refrigerator. This is where it absorbs the heat present in the system and cools the surrounding air. In the process, it turns to gas again due to the low evaporation point. This gas is again pushed to the compressor, and the process continues repetitively.

History of Refrigerant Gases Used in Refrigerator

Initially, during the 19th century, a mixture of Chlorine, Fluorine, and Carbon was used as refrigerant gas. But with the advancement in technology and research, it was discovered that these chlorofluorocarbon gases are toxic to the earth’s atmosphere. When these gases reach the atmosphere, they underwent a chemical change coming in contact with the UV rays from the sun. The result led to the greenhouse effect, global warming, and, most importantly, ozone layer depletion.

After this revelation, new refrigerant gases came to the surface. The two most widely used refrigerant gases are HCFC and HFC. HCFC is a mixture of Hydrogen, Carbon, Fluorine, and Chlorine. HCFC has a relatively short lifespan, due to which even when they expose to the atmosphere, they will not sustain for long. Hence, the chances of causing atmospheric damage are a bare minimum.

HFC is even a better option as it is a mixture of Hydrogen, Carbon, and Fluorine. Due to the absence of Chlorine, there is a negligible harmful effect on the environment. This is the reason why modern refrigerators have HCFC and HFC as refrigerant gases. The following section specifically focuses on the refrigerator gases used in refrigerators in detail.

Different types of Gases used in Refrigerator

R-22 Chlorofluorocarbons – This is the most common refrigerant gas in old refrigerators. It was the prime candidate behind ozone layer depletion. However, it is no more in use in modern refrigerators.

R-438A Freon – This is the perfect replacement for R-22 Chlorofluorocarbons as it does not cause any ozone depletion. That is why it is the refrigerant gas you will find in modern refrigerators.

R-134A Tetrafluoroethane – Even though this gas does not lead to ozone depletion, it is a potential candidate for the greenhouse effect and global warming. However, it is present in modern refrigerators as stopping ozone depletion is more important than global warming. Besides, it is easy to condense, and that is why it makes the refrigerator energy-efficient. It is quite popular since the early 20th century as it is always easily available.

Hydrofluorocarbons(HFC) – Refrigerant gases started with Chlorofluorocarbons(CFCs) and then Hydrochlorofluorocarbons(HCFCs) came into the scene. Now, HFCs are replacing HCFCs due to the absence of Chlorine, and many countries are phasing out HCFCs and replacing them with HFCs.

Acrylonitrile – This insulator is present in some modern refrigerators. It acts as a barrier between the heat of the surroundings and the coldness of the interior of the refrigerator. This insulator is easily available and convenient to clean, which is why it has become an automatic choice.

Polystyrene – This is another insulator that acts as an internal padding to prevent the interior from heating up due to surrounding air. Due to its wider availability and relatively less cost, it is also quite popular in the refrigeration industry. Earlier, it was used as an alternative to harmful refrigerant gas.

R-600A IsoButane – It is a highly flammable refrigerant gas, and it is only present in small and budget refrigerators.


1. What happens when the fridge runs out of gas?

Ans: When the fridge runs out of gas completely, the interior will stay rather warm instead of cold or normal. The interior will smell foul as if you have not used the fridge for days. The motor will keep running continuously and make unusual continuous noise.

2. What happens if the gas is low in the fridge?

Ans: When the gas is low, the food inside the refrigerator will start freezing. You will also find that items like eggs and milk are also freezing. With further low level of gas, frosting is a common phenomenon witnessed whereby you will find chunks of ice forming in the trays, grills, walls that are inside the fridge. The motor will run for a longer time, and you will notice a considerable increase in electricity consumption.

3. How toxic are these refrigerant gases?

Ans: Refrigerant gases are very toxic for the environment as well as human beings. If they escape into the atmosphere, their chemical structure changes because of coming in contact with the UV rays of the sun. That is why they get activated to react with the ozone present in the ozone layer of the earth. This leads to the depletion of ozone from the layer and the formation of holes for harmful rays to hit the earth’s surface and human skin.

On a personal level, refrigerant gases are harmful to breathe in. Mild inhalation leads to headache, irritation of eyes and throat, vomiting, nausea, coughing, and dizziness. Severe inhalation and poisoning can lead to burning sensation in the lungs, coughing up blood, difficulty in breathing, seizure, and loss of consciousness.

4. What is the average life of refrigerants in the fridge?

Ans: If there is no leakage, the average life of a refrigerant is 15 to 20 years. The life span of the refrigerant is equal to the life span of the refrigerant. However, it depends from one model to another, and a compact refrigerator is likely to have less life span for its refrigerant. If you know the signs and symptoms of low refrigerant gas, you can refill timely.

5. How do I know if my refrigerant gas is leaking?

Ans: You can smell the leaking refrigerant gas if there is considerable leaking. However, most of the leakages are not detectable by smell as they are minor but eventually, the gas in the cylinder can become low.

You will see that the interior is taking a relatively long time to reach the low temperature than usual. That is why you will also find the motor running continuously. The refrigerator is also likely to become noisy.

6. Why is Freon gas used in the refrigerator?

Ans: There are multiple reasons why Freon gas is used as a refrigerant in the refrigerator. First of all, it does not cause ozone layer depletion when they go out in the atmosphere. Secondly, it is a non-flammable gas, and there is no risk of unforeseen circumstances in case of any major leakage from the refrigerator. Thirdly, it has a low evaporation point which is why the conversion from liquid to gas state becomes fast, and thereby, the cooling process also becomes quicker.


You should not compromise with quality when buying a refrigerator. This is because a good-quality refrigerator from a popular brand will have the best possible refrigerant gas that is least harmful to the environment. You can also check the specifications and manuals of the refrigerator before purchasing to make sure the refrigerators are as per the modern standard. Hopefully, this guide will help you in your next purchase.