What Size Air Conditioner Do You Need?

Choosing the right sized air conditioner for your home is very important to ensure you get the most out of it. If your air conditioner is too large for the space, it could run inefficiently and through more cycles than it should, resulting in more wear on the unit and its components. An air conditioner that is too small could be running at full power to make up for the reduced capacity which can make the air dry and also result in more wear on the unit and its components.

If you’re considering getting air conditioning installed, refer to this handy chart so you get the right capacity for your space.

When choosing your air conditioner size, it is usually a good idea to select a model that has a slightly higher capacity than the room needs. This allows the air conditioner to maintain comfortable levels during any extreme temperature periods. For example, if your space requires a 5kW air conditioner, you should probably look for an air conditioner within the 5kW-5.5kW range. You do not need to go much higher than the capacity you need.

As important as it is to know the right capacity for room sizes, it is just as important to accurately calculate the size of the space.

How to accurately calculate room size

Doing a basic measurement and analysis of a room may result in recommending a larger capacity air conditioner than you actually need. There are a variety of factors to consider. Things like insulation, orientation (i.e. with west-facing windows) and location can significantly impact your heating and cooling needs for a room.

To accurately calculate the requirements for your room, you need to consider:

• The rooms measurements: length, width and height

• The type of room (i.e. bedroom, open-plan living room, etc)

• The position and size of windows and doors • Any insulation in the walls, floor and ceiling

• The climate where you live

The Australian Institute of Refrigeration, Air Conditioning and Heating (AIRAH) has created a tool to calculate the cooling and heating load your room requires and allows you to factor in many of the details mentioned above. If you use calculators on manufacturer websites just be mindful that they generally overestimate the size of air conditioner you room needs.