Keeping cool can be done with precision and efficiency when you know exactly what size air con you need based on the size of your space.

When it comes to keeping cool, air cons are one of the most popular means here in Sydney. But if your system breaks or seems to be fighting just to combat the heat, you might be wondering what size air con you really need. After all, there is no one size fits all solution when it comes to air conditioning.

Air cons come in a variety of types, shapes, and sizes. And it’s important whether you’re installing new or replacing an older unit to be sure you have the right size for your space. This will help you keep your energy bills to the minimum while keeping the heat at bay at the same time.

It starts with some mathematics

Air con sizes are a product of some basic calculations. All you have to do is determine how many square metres you need cooled. This can be done per room for a split system air con by multiplying the width and length of your space to give you the area, or square metres. For a multi spilt or ducted system, you’ll just add together the combined areas of every room you want cooled to give you the total square metres.

After you’ve measured and done your math, you can then determine the size air conditioner you need.

On average, you’ll want 150 watts of power per square metre of space you want to cool.

Other factors that affect air con sizes

Size is the predominant factor when you’re deciding what size air conditioner to get for your space. It’s why we started with the math above. However, there are other less formulaic factors that can impact this decision. Here are a few more for you to consider when talking with your electrician:

  • Insulation: Are the walls, ceiling, and roof adequately insulated to keep the heat out and the cool in?
  • Direction: Is the room facing north or west, which can let in much more sun and, thus, more heat in the summer?
  • Location: Take into account where you live, since here in Sydney our summers tend to be extra hot and aircons can get overpowered.
  • Windows: Consider that more light means more heat created and entering the space via the sunny rays.
  • Appliances: With fixtures and appliances that run and add heat to a space, you might need more help cooling than you’d expect.
  • People: The number of people not only add heat to your space but also place demands on your utilities and appliance use, which can affect cooling.

What size air conditioner do I need?

With all of these factors and your math in mind, you can determine fairly easily which size air con you’ll need for your space. To help, here’s a table that breaks down sizes and efficiency for you.

Air Conditioner Size/Capacity Area in Square Metres
2.0kW 20
2.5kW 25
3.5kW 35
5.0kW 50
6.0kW 60
7.1kW 70
8.0kW 80

What happens if you get an over or under powered air con?

It might not sound like such a bad outcome to have an under or over powered air conditioner. Of course, with an underpowered air con, you’ll probably be much warmer than you would have been with a right-sized system. And with an over powered air con, what’s the worst that can happen other than being a bit chilly when things heat up?

Actually, the effects of a wrongly sized air con are much more than just temperature control issues. You’ll probably quickly see the trend that there are issues with comfort and costs. Here are some things to consider if:

Your air con is too large for your space

  • Issues with dehumidifying the air properly
  • Increased power use above what’s needed
  • Higher costs to operate the system on your electric bill
  • Higher costs to repair and maintain a larger system

Your air con is too small for your space

  • Issues with dry and uncomfortable air
  • Increased costs for power use while it runs nonstop
  • Higher costs to operate the system on your electric bill

Still not sure? Ask HunterCON for expert air con advice

Air conditioning is something you’ll want to get done right the first time, especially if summer is beginning to approach here in Sydney. To that end, you’ll want to make sure to carefully measure and understand how you use your space to choose the right size system for your home.

That said, it can be overwhelming to make such a decision on your own. And there could be other factors to consider, such as which type of system might work best for your space, not just what size. That’s why so many homeowners here in Sydney turn to the experts at HunterCON not just for installation but for advice and consultation as well.

Looking to make your home more energy efficient? We wrote the guide on it (literally)

Our team of licensed and insured air conditioning specialists and electricians can give you a free quote and visit your exact space to help you determine the right type and size system for your home. We’ve seen everything from underpowered ducted systems to split systems sized so large that living rooms can resemble an ice box. When we arrive on the scene, we start with a complete consultation so that whatever you choose, you can be confident that it will be the right fit for your space moving forward.

Call us on (02) 8283 1105 or request a 100% obligation-free quote online today!