What Size Air Conditioner Do I Need?

If your air conditioning unit is too small, it just won’t be able to maintain your home at the temperature you want it to. It will work so hard to do the job that it will use way more electric than you expect, too.

However, using an oversized system won’t win any prizes, either. A unit that’s too large will constantly turn on and off, increasing strain on the compressor and your energy bill.

It’s not simply a question of energy efficiency when selecting the right size air conditioner: the choice is a little more complicated than selecting the best looking unit with the highest energy rating. Here we look at how to decide what size air conditioner you need.

Start with the size of your living space

A larger room will need more cooling capacity, and it is this that will be the main factor in determining the required size of air conditioner unit. Not only will you need to consider the size of your rooms, but also their use: the more use your rooms receive, the more air conditioning they will need.

It’s not simply a fact of measuring floor space, either – rooms with high ceilings need a different air cooling capacity to those with lower ceilings.

Shady or sunny?

Second, you’ll need to consider the aspect of your home and the room(s) you want to cool. A room which is bathed in sunlight all day will need the air conditioner to work harder, and that will mean a bigger size of air conditioner.

What type of insulation do you have?

Poorly insulated rooms may let out the heat during the winter, but they also affect internal heat in the summer too.

How many people need cooling down?

Finally, the more people there are in the air conditioned space, the larger the air conditioning unit you’ll need. People give off heat, so for every extra person that lives in your home (or works in your office, if the air conditioner is for your workplace you’ll require that little extra air conditioning power.

Making the decision

It’s perfectly possible to measure your home and estimate the size of air conditioner you need, but to ensure the size is correct you need also to factor in aspect and inhabitant numbers, as well as use and insulation..

This calculator from the Australian Institute of Refrigeration will help you to estimate the size of air conditioner needed for your home, but in order to gain an accurate calculation you should consult an expert. They will have the tools and experience required to ensure your air conditioner is the right size, giving you maximum room temperature efficiency at lowest running cost.