Which Gas Is Used in ACs?

A lot of people think that air conditioners work by pulling in hot air from the room and releasing it outside. This is a common misconception as AC pulls in the hot air from the room, processes it, and blows it right back into the room. This cycle is repeated until the target temperature is reached. Your AC uses gas to achieve this, and this raises a question, which gas is used in AC?

Which Gas Is Used in AC and How Does It Cool the Room?

An AC works quite similar to how a refrigerator does, only in this case you are inside the refrigerator. As to which gas is used in ACs? The answer is freon, a chlorofluorocarbon (CFCs), which is a non-flammable gas that undergoes continuous evaporation and condensation cycles to keep your room cool.

A Brief History of Freon?

CFCs were first created in 1890, but they were dangerous and flammable. These properties are quite the opposite of that of Freon. So, how did we get here? During the 1920s, a team at General Motors was looking for a non-toxic and non-flammable form of CFCs. They worked with DuPont and managed to produce Freon in the 1930s. Freon is colorless and is also called R-22. The name Freon is a trademark of DuPont, and it has been used since then in refrigerators and until early 200s in air conditioners.

How Does Freon Work?

Now that you know which gas is used in ACs, you might be wondering how it works? The working of Freon in AC requires some coiled pipes, a compressor, and some science. The compressor compresses freon and suddenly releases it into the pipes. This process allows the gas to expand and gases cool when they are allowed to expand suddenly. As the cold freon goes through the pipe, it condenses and flows as a liquid. Now, the air sucked in by your AC is passed around these pipes. The process cools down the air, which is circulated into your room. Thus, making the room cool.

Ban on Freon?

Freon was used widely as a refrigerant since its inception until the early 21st century. During the late 20th century, it was discovered that freon was causing damage to the ozone holes, and in 1987, the Montreal Protocol was proposed, which aimed at reducing the use of CFCs. At first, the use of CFCs in aerosol sprays was stopped, and later on, its use was reduced in the ACs as well. However, some air conditioners still rely on freon for their functioning.

Which Gas Is Used in ACs Today?

If your ACs were manufactured after 2003, then there is a 90% probability that it doesn’t use freon. So, which gas is used in ACs now? The answer is HFCs (Hydrofluorocarbons); they have a better cooling potential than the CFCs and are less harmful to the environment. The HFCs that is used in today’s AC is called R-410A and is further a mixture of two HFCs called R-125 and R-32. The best thing about R-410A is that it is totally safe for use as it doesn’t cause any harm to the ozone layer. However, all is not green about this new gas. A study shows that HFCs are a kind of greenhouse gas that causes global warming. However, further studies proved that HFCs contribute less than 1% of global warming. The higher cooling capacity when compared to the older CFCs and significantly less impact on the environment has kept HFCs from being phased out. Still, researchers are working on finding new and safer alternatives to HFCs.

Which Gas Is Used in ACs instead of HFCs?

As mentioned earlier, HFCs are greener than CFCs but are responsible for global warming, even though they account for less than one percent. So, many alternatives are being considered to replace HFCs in the future. Some of them are already being used. So, let us take a look at some of these alternatives.

Carbon Dioxide

Now, before you say that, “isn’t Carbon Dioxide a greenhouse gas and that too a popular one?”

Well, Carbon Dioxide isn’t exactly fun to work with in terms of cooling. It requires a lot more effort when it comes to compression and makes the technology expensive. However, recent developments have reduced the costs and on looking at the global warming potential of Carbon Dioxide, which is one as compared to over 14000 for commonly used HFCs, and it is also cheap to obtain. Thus, Carbon Dioxide is a good alternative to HFCs.

Ammonia

Ammonia is one of those HFC alternatives that is widely being used in the industry. It doesn’t harm the environment, is a lot safer and cheaper to produce. It is used in large refrigerators and centralized air conditioning units. It also has no contribution to global warming at all.

Hydrofluoroolefins

They are the most promising alternative to HFCs. They are synthetically produced, have zero impact on the environment, and if they happen to leak, then they break down within a few days.

FAQs

Which Gas Is Used in ACs?

Most ACs made after 2003 rely on HFCs for cooling, whereas older ACs use Freon.

Why Was Freon Banned?

Research in the late 20th century linked CFCs, a family of which freon is a part, with ozone layer depletion. As a result, the Montreal Protocol was established in 1987 with the purpose of phasing out the use of CFCs before the 21st century.

Which Gas Is Used in Newer ACs?

Most ACs made after 2003 rely on a class of synthetically produced gases, which are called HFCs (Hydrofluorocarbons). These gases are a lot efficient at cooling than CFCs, and they don’t harm the ozone layer.

Do HFCs Cause Global Warming?

The answer to this question is yes. However, HFCs account for less than 1% of the gases that are responsible for global warming.

What Are the Alternatives for HFCs?

The main alternatives to HFCs are Carbon Dioxide, which is a lot lower on global warming potential than the HFCs. Ammonia is also an alternative that is being used widely. Lastly, there are Hydrofluoroolefins, which are considered as the best possible alternative to HFCs.