Over the past few decades, air conditioners have become more of a necessity than a luxury in our lives – we come across them at work, home, and even when we’re out and about. However, unless you’re an engineer or a science-minded sort of person, you might never have really paid much thought to how they work. Switch on an air conditioner and it just miraculously cools or heats a room, right?
By understanding the basics of how your unit works, making minor adjustments to the settings can have the ability to reduce operating costs.
Let’s start with an anatomy lesson.
You might think of an air conditioner as a nice neat box on the wall (or in your roof space) with a unit outside – but rest assured there’s a lot more to a system than this. No matter what type of air conditioner we’re talking about (split system, multi-split, or ducted) every air conditioner will have the same key components. We’ve broken these down below so you know the purpose of each one.
Evaporator. This is essentially a coil located in your indoor unit, with refrigerant flowing through it. In cooling mode, with the help of a fan your indoor unit continually draws in hot air over these cooling evaporator coils, and blows it back into the room at a much lower temperature. As the refrigerant absorbs heat, it transforms from a liquid to a gas.
Compressor. So, what happens to the heat collected inside? Well, it travels through tubes to a compressor located in the outdoor unit. The main job of the compressor is to compress low pressure refrigerant gas into a high pressure refrigerant gas, so the heat can be expelled outside.
Condenser. This is a second coil that’s located in the outdoor unit, which receives hot, compressed refrigerant gas. With the help of a second fan, it then expels this heat into the external atmosphere, condensing the refrigerant gas into a liquid.
Expansion valve. This is the final key piece of the puzzle. In simple terms, it works to regulate the flow of refrigerant into the evaporator (starting the cycle again).
Combine the key elements and what happens? Well, your system essentially works on a heat exchange loop. The refrigerant in your unit’s coils moves between the indoor and outdoor units, carrying heat from one space to the other. In summer, the heat is absorbed from inside your home and exhausted outside leaving your home cooler. In winter, heat is absorbed from the outside air and used to heat your home.
The role of refrigerants.
We mentioned refrigerants earlier, as they’re fundamental to the air conditioning process – but what makes refrigerants so special? Primarily, it’s down to their ability to switch between gas and liquid states so easily.
The most common refrigerants today are R-32 and R-410A. While both are hydrofluorocarbons (HFC), R-32 is a better option because it has a significantly lower global warming potential (GWP) – and this is what most Daikin air conditioners use. In fact, Daikin was the first to introduce R-32 back in 2012, and to facilitate adoption by other manufacturers, Daikin granted free access to the R-32 patent for other manufacturers to use. This reflects Daikin’s support of the Kigali Agreement, a global initiative to phase down HCFCs and reduce the environmental impact of air conditioning refrigerants. Today, Daikin units utilizing R-32 refrigerants are sold in over 70 countries worldwide.
Let’s not forget that moisture matters too.
When it comes to heating and cooling, the amount of water vapour in the air (humidity) is an important factor. The human body finds it harder to self-cool in a humid environment – so, when cooling, an air conditioner will also dehumidify the air. On the other hand, those that have asthma or allergies may find air that is too dry, irritable and uncomfortable. Air conditioners such as Daikin’s US7 integrate features that can balance the humidity indoors to create a more ideal and more comfortable environment.
Some air conditioners can also effectively filter the air too. Daikin split systems are all Sensitive Choice approved by the National Asthma Council of Australia thanks to the inclusion of an advanced Titanium Apatite Deodorising Air Purification filter. These filters not only trap most microscopic airborne particles, but also assist to decompose odours, absorb and deactivate bacteria, so they’re a great option for anyone concerned about the cleanliness of the air they’re breathing.
Hot air rises… what does this mean?
One scientific principle that’s useful to consider in the context of air conditioning is the fact that hot air rises. This is because, as air heats up, it becomes less dense than the air around it – and it floats to the top in the same way a cork floats in water.
If you have a split system, when angling the louvres in cooling mode, point it towards the ceiling so the air can fall naturally to cool the entire space. During winter when you need to put it in heating mode, tilt the louvres down so the warm air can heat the space starting at your toes before the warm air rises.
Got any more questions about the science of air conditioning? Our experts will be happy to help explain the ins and outs – just contact your local Daikin Specialist Dealer.