What is an Aircon Refrigerant and How Does it Work?

Like most appliances found at home, air conditioners need power and electricity to function and work properly. But apart from this, there are other parts and components that are equally as important in making an air conditioner cool any given room. One of these essential components is the refrigerant — a liquid or gaseous compound that absorbs heat and readily provides refrigeration to the aircon unit together with its other main parts.

You may have heard the AC refrigerant together with an aircon gas top-up, as the latter is always suggested after every aircon cleaning by most aircon service providers. Although it may seem like it’s an optional component, the air con refrigerant is a very vital element to an air conditioning system. Without it, there would be no air conditioning or even refrigeration and freezing technology.

In this article, we will discuss how exactly an AC refrigerant works in the air conditioning system and its different types.

How Refrigerant Works in AC?

Step 1: Compressor -  In order to get a clear picture of how a refrigerant works, let’s look at how it moves around the system. The aircon compressor, which is considered as the heart of an aircon system, forces the refrigerant around every component located in the refrigeration system. Afterwards, the refrigerant will make its way inside as a saturated vapor in the form of a low temperature and low pressure gas. It then gets pulled in by the compressor, causing it to rapidly compress and forces the molecules together — this results in the molecules of the same amount fitting into a smaller volume. These molecules are all going around by compressing them into an even smaller space, causing them to collide more and interact with each other. Once this reaction happens, their kinetic energy will be converted into heat. Simultaneously all the energy exerted by the compressor will be converted into internal energy within the refrigerant. This gives way to an increase in internal energy in the refrigerant’s part. It also increases in enthalpy, temperature and even pressure.

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Step 2: Condenser - The next step that happens is that the refrigerant moves to the condenser. When it enters the condenser, its temperature will need to be higher than the ambient air surrounding it for the successful transferring of heat. So the greater the difference is in the temperature, the more likely and easy it is for the heat transfer to take place. The refrigerant then enters as a vapor that is heated at high pressure and temperature, passing inside the tubes of the condenser. Afterwards, the fans will begin blowing across the condenser to eliminate any unnecessary and unwanted energy. As the air goes through these tubes, the heat associated with the refrigerant gets removed. As heat is eliminated, it will condense into a high pressure liquid that is decreased in both enthalpy and entropy.

Read also: Common Aircon Condenser Problems

Step 3: Expansion Valve - Once the refrigerant enters the expansion valve, the latter begins metering the refrigerant’s flow into the evaporator. The valve will also adjust to permit some flow to the refrigerant, now in part liquid and part vapor. Once it passes through, the valve will function by filling in the void. The refrigerant then further reduces in pressure and temperature with this expansion. Afterwards, it leaves the expansion valve to make its way into the evaporator.

Step 4: Evaporator - Once the refrigerant makes its way inside the evaporator, the latter receives it with the support of a fan blowing warm air from the room across the coil. Since the temperature of the air from the room is higher than the cool refrigerant’s temperature, this allows it to get more energy and have it boiled completely into vapor.

Step 5: Refrigerant Vapor - After the refrigerant exits the evaporator as a low pressure vapor, its low temperature only slightly changes. The reason for why it doesn’t increase exponentially is because of a phase change that happens from liquid to vapor. One can expect a temperature change once the fluid is no longer in this phase.

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Refrigerant Types Used in Air Conditioners

Now that you know how it works in an air conditioning system, it’s time to go over the different types of common refrigerants:

1. Chlorofluorocarbons (CFCs) and R12 - The CFCs were an older and now-defunct type. Since this refrigerant was largely associated with contributing to the greenhouse effect and global warming, its production was entirely ceased back in 1994.

2. Hydrochlorofluorocarbons (HCFCs) and R22 - Although considered less damaging than the CFCs and R12, the R22 has nevertheless also been phased out by the EPA in compliance with the Clean Air Act of 2010. This type is expected to completely phase out by 2020.

3. Hydrofluorocarbons (HFCs), R410A and R134 - A safer option than the previous types, the R410A and R134 have no chlorine in the mix and are considered safer for the environment. They are also being used in place of the R22 and aircon units using them are found to be more efficient, reliable and capable of producing better cooling, air quality and comfort.
   
   

Caring For Your Aircon

If you need to have your AC refrigerant gas refilled, we recommend calling a leading aircon service provider. Since these top-ups are important for your aircon unit to give proper cooling, it is best to do this regularly along with a proper maintenance check from a team of aircon experts.

Oasis Aircon is a leading Singaporean aircon service company providing a broad range of services for aircon owners in Singapore, including aircon repair, aircon chemical wash, aircon installation, and gas top up services for different unit types. Each service is priced competitively to ensure that your aircon performs at its fullest potential and capacity.