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Are you in the market for an air conditioner but unsure exactly what size system you need to suit your room or space? Here’s some advice on why getting the correctly sized air conditioner is so important and how to avoid some issues we see regularly.

An air conditioner for one room only?

Many people are under the impression they can install one split system and it will cool or heat the entire house. This isn’t the case; most split system air conditioners are designed to cool/heat one room only. This is because the head unit pushes the air out the vent and then recirculates it back at the top of the indoor unit.

Choosing a split system that is too small

When you’re buying an air conditioning system it’s easy to go for a small unit (as they are the cheapest) however, this isn’t always the best solution. If the system is too small for the area it is installed in, it will struggle to cool or heat the area, pushing your electricity consumption higher. The air conditioner may also never get the area to the set temperature, putting a strain on the unit which can lead to increased breakdowns or a reduced useful life. In some cases, the unit may be void of its warranty if it is installed or used in an area too big for its specifications.

Buying an aircon that is too large

If the system is too large for the area it can “short cycle” meaning it will switch on and off too fast, as the room gets to temperature quickly. This can damage the compressor in the outdoor unit and reduce the life expectancy of the system. If the system uses R32 gas it’s important the unit isn’t oversized as the gas is explosive and in the event the unit drops its gas charge could potentially fill the area to dangerous gas levels.

air con unit

Here are some other things to consider before you buy an air conditioner

  1. Any split system 5kW or over will need a new electrical circuit from the meter box or sub-board to cope with the power demand safely.
  2. Bulk stores are happy to sell any size to you, even if they aren’t the correct rating opt for a custom quote to ensure you are getting the right unit.
  3. You may void the warranty if you go too big or small with the system.
  4. All split systems have a 5-year manufacturer’s warranty.
  5. Not all installations are the same. Correct install is essential to the unit operating effectively and efficiently.

How do I calculate what size air conditioner I need?

We recommend seeking the services of an experienced air conditioning technician. The aircon technician will provide a system to suit the specific room size, heat loads, ceiling heights, insulation, floor coverings, and floor area design layout.

To get an idea of the size you’ll need for a standard room you can calculate the area by the following. Firstly, measure the width and depth of the room. Then multiply the two together. Eg. 5 meters x 4 meters = 20m2 Floor Area. Then you need to multiply this by 150 watts. Eg. 20 x 150 = 3000 watts or 3kW.

Please Note – this a very basic guide based on room size only. We recommend always consulting with your local air conditioner specialist for accurate sizing taking into consideration all factors.

Need a quote from a split system expert?

If you’re looking to get an air conditioner and want clear accurate advice from a qualified expert, give Static Electrics a call on 1300 206 004 or complete an online job booking form and we will ensure your system is sized correctly.