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What size aircon do you need?

Sometimes people think that the bigger the better, and they opt for the biggest air conditioner they can find on the market, but this couldn’t be further from the truth. There are many factors you must keep in mind when buying an air conditioner and designing an air conditioning system for a room.

For example, you should consider the size of the room, the insulation of the house, and where you are going to place your aircon unit/s.

Also, buying an air conditioner is such an important purchase that you never want to have to do it by impulse or in a rush. Ideally you can do your research first and make a purchase based on what is most suitable for you and your home.

Why you should buy the correct aircon size?

When it comes time to choose the correct air conditioner it is important to respect the relationship between power, space, and temperature.

Some people believe that it is better to buy the biggest and most powerful air conditioner to avoid having problems in the future. Alternatively, many people believe that buying a small air conditioner, without making the appropriate calculations, is the best option as at the end of the day everything will cool down eventually.

However, if the air conditioner is too big for the given area, the air will cool down very quickly but the humidity in the space will stay there, which generates discomfort in the environment.

On the other hand, too little power for a big space will strain the compressor and whole system too much, and will make the aircon work harder. Also, the air con will not be able to cool or heat the place in its totality.

For this reason, you should do yourself a favour and assess the area of the room (m2), the cooling capacity (BTU) needed, and the size of the aircon (KW) required.

Comfortable Temperature with Aircon

What is a BTU?

BTU stands for “British Thermal Unit” and it is essentially a measure of the amount of heat an air conditioner can exchange. Keep in mind that as the BTU rating increases, so does the size, weight and cost of the aircon. 

Nowadays there are many measures for air conditioning, but BTU is one of the original methods and is still used today. Also, you should know that the higher the BTU amount is, the more heat exchange (heating or cooling) the device will offer.

How to calculate correct air conditioner BTU size when buying an aircon?

An air conditioner of insufficient BTU will not be adequate to cool a room, or it may take too long to do so, especially if the ambient temperature is particularly high. Similarly, it will fail to heat a room completely, or could take a long time doing so.

With the following calculation method, you will be able to determine the BTUs of an air conditioning system needed to cool down a room with 1 to 2 people inside.

You can see here an example of how you should calculate it:

  • Room volume: Length x Width x Height = X, then divide X by 2.
  • Example: Length 3m x Width 3m x Height 2m = 18m / 2 = 9m.
  • With the answer obtained 9, it could be said that between 9,000 and 12,000 BTU is required.

In general, a 6k BTU air conditioner may be perfect for a small room between 8-12 m2, 12k for a bigger room from 12 to 16 m2, 18k for a small living room or dining room, and a 24k for a big living room.

Aircon in Living Room

What other aspects you should consider?

The insulation of the room

The first thing you want to do before buying an air conditioner is make your home thermally efficient. This it can affect the ability of a house to maintain temperature. Also, if your house is well insulated, you won’t need as greater cooling or heating capacity as you may think.

Ceiling insulation is one of the biggest factors in making your home thermally efficient. This will help you manage the size of air conditioner you need and will also save you money.

Not only will you save when buying the air conditioner but also in the long run because a smaller air conditioner means less energy consumption. That means a smaller monthly or quarterly energy bill.

The orientation

It is important to consider the orientation of the room where you are going to place the aircon. If it is facing North, East or West, if it is going to get full sun, or if it will be well shaded.

For example, when a house is facing East, it is heated in the morning and then potentially cooler during the rest of the day. This means that the house’s orientation will determine the solar radiation that it will receive during the day.

Also, you have to be aware of factors such as the window’s location, the kind of ventilation that will be available in the room, and if any heat-generating appliances will be close to the aircon.

The location

Keep in mind that the location, meaning the place where you live, is also important because it goes hand in hand with the previous point (orientation).

If you live in a place where it is sunny the majority of the day and the orientation of the house favours the entry of sunlight, then you will require a different size of aircon. This is compared to one you will need if the place where you live is cooler and your home location favours shadows in the interior.

To make exact calculations you can use this amazing calculator to determine the exact size of air conditioner you will need.

However, the most accurate way to find out the air conditioning capacity required to is to contact a professional.

At Ice Blast, we are happy to help you. Thanks to our many years of experience we can assess and provide the most accurate estimate for your air conditioning needs.