What Size Air Conditioner Do I Need?

Buying a new AC for your home in Melbourne can be a challenging task. Although you have to bear in mind several practical considerations, nothing beats the importance of choosing the right size AC to cool your space. As it is a significant investment, you don’t want to rush into a decision. Even a rough estimate of AC size could compromise the unit’s efficiency and cooling capacity.

What size of split system air conditioning need?.

Surprisingly, many of us assume that all air conditioning systems are the same. After all, they operate by following the same principles and provide cooling. However, that is not the case at all. Finding the right-sized Air Con Melbourne  depends on numerous factors such as insulation, room size, number of windows, ceiling height and more.

In just 2020, Australians spent $3.7 billion to stay cool over the summer period. It’s estimated that Aussies will spend way more in the coming years. Although over-usage is part of the reason behind the rise in energy bills, the biggest culprits behind energy bills hitting the roof are insufficient insulation and wrong-sized air conditioners.

How To Calculate Air Conditioner Size?

To find out what size air con you need, start by measuring the square footage of a room. To do that, you need to apply the following formula:

Measuring Square Footage of A Room

If the room is square or rectangular: Room’s Width x Length = Square Footage (room area)

If the room is triangular: Width x Length / 2 = Square Footage (room area)

Split System Air Conditioning Sizing (Capacity)

Split system air conditioning is widely popular in Australia. Once you know the room area, multiply it by a factor of 0.15 to find the unit’s power needed – kilowatt (kW) – to cool a room. For example, you’ll need a split system AC unit of 6 kW to cool a room area of 40sqm. In Melbourne, experts recommend selecting a 2.5 kW unit for adequate cooling of 10-20sqm room areas.

Ducted Air Conditioning Sizing (Capacity)

Ducted refrigerated air conditioning is ideal for whole-house cooling. To determine the size capacity (kW) of a ducted air conditioning unit, you need to multiply the daytime cooling area (m2) with 150 watts. For example, the ideal size for cooling 100m2 would be 15 kW.

Important Note:

These formulas can only provide a rough estimate of what size air conditioner you need because you’ll have to consider other variables such as insulation, ceiling height, number of occupants in the room, the rating of ducted insulation.

Do check this air conditioning size calculator to find out the estimated size of your split or ducted air conditioner.

Read More: What is Ducted Refrigerated Air Conditioning?

So, What Size Air Conditioning Unit Do I Need In Melbourne?

For split system air conditioning, the following table can provide a rough estimate of what size AC unit you need:


Learn More:
How Much Does It Cost To Run An Air Conditioner.

Factors to Consider When Calculating Air Conditioner Size

The room size alone isn’t the only factor you need to consider when sizing an air conditioner. These are some factors that you need to be considered as well:

  • The type of room: bedroom, living room, or kitchen
  • The size of windows and their orientation (how much sunlight they face in a day)
  • The insulation of the roof, floor, and walls
  • Number of occupants
  • Does the room face direct afternoon sun?
  • The local climate

The Disadvantages of An Oversized Air Conditioner

In our line of business, we have seen so many oversized air conditioners installed that it doesn’t surprise us anymore. That’s why we always try to inform readers about the drawbacks of installing an oversized air conditioner.

One of the apparent downsides is that the system will short cycle a lot. It is because an oversized air conditioner will quickly cool the place and then start to turn on and off because of temperature fluctuations.

To think that an oversized system will cool your place quickly and save energy is entirely wrong. In reality, the system will use more power to provide a quick burst of cooling before turning off, and then repeat the process because it won’t be cool enough in the room.

Short cycling will not only consume more energy, but it will also increase the possibility of a breakdown and repairs. In short, you might be stuck with a power-sucking AC unit that will only make things worse for you in the future.

The Disadvantages of An Undersized Air Conditioner

If you get an undersized air conditioner, it could turn out to be an even more expensive mistake because the unit will be running most of the time to reach your desired temperature. And if the unit reaches the temperature, it will fail to maintain it.

Non-stop running could escalate wear and tear. It could affect the efficiency and longevity of the unit as well. In short, you could be paying way more after saving a little from buying a smaller unit.

Consult With Professionals

Air conditioning is an investment that is meant to benefit you for many years. Therefore, selecting the correct sized air conditioner for your Melbourne home is vital to achieving unit’s prime performance and energy efficiency. Instead of rushing the decision based on recommendations of non-experts (yes, we are talking about your neighbours), it would be best to consult with professionals who have years of experience in this field. In other words, consult with ComfyHome for precise measurements and recommendations of what size air conditioner you need.

You may want to know about the best air conditioning brands in Australia before selecting the right size AC for your home. If you have any inquiries about the sizing of the air conditioning unit, please feel free to contact us.

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