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What size air conditioner do I need?

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

Small Split System Air Conditioners

Air Conditioner Split System open

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; a split system air conditioner is designed to cool/heat one room only. This is because the head unit pushes the air out the vent and then recirculates (sucks) it back at the top of the indoor unit.

Small Split System Air Conditioners

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, tit will struggle to cool or heat the area, pushing your electricity consumption higher! The Air Conditioner will also never get the area to the set temperature and will put a strain on the system. In some cases, the unit may be void of its warranty if it is installed or used in an area outside its specifications. it cannot as its incorrectly sized for the area.

Big Split System Air Conditioners

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 if R32 gas its important the unit isn’t over sized as the gas is explosive and in the event the unit drops it’s gas charge could potentially fill the area to dangerous gas levels.

Split System Air Conditioner

Here’s 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.
  2. Bulk stores are happy to sell any size to you, even if they aren’t the correct rating.
  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. e.g. You get what you pay for!

How do I calculate what size air conditioner I need?

A refrigeration technician will generally design as system to suit the room size, heat loads, ceiling heights and floor area design layout. To get an idea of the size you need for a standard room you can calculate the area by the following. Firstly, measure the rooms, width and depth. Then multiply the two together. Eg. 5 meters x 4 meters = 20m2 Floor Area. Then you need to multiply this by 150watt. Eg. 20 x 150 = 3000watt or 3kW. Please use this a very basic guide and you should always consult with your local refrigeration specialist for accurate sizing.

Need a quote from a split system expert?

If your looking to get an air conditioner and want clear accurate advice from a qualified expert. Give us a call on 1300 139 004 or complete an online job booking form and we will ensure your system is sized correctly.

Air Conditioning,
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At Static Electrics, we are passionate about our work and offer a 100% customer satisfaction guarantee on every job. From the initial booking, through to the completion of the job, we will take pride in every step of the process. Our customers can expect to be greeted by a friendly office team member, either by telephone contact, email or SMS. For more specific electrical or air conditioning advice, customers’ requests may be transferred through to one of our experienced estimators for further assistance. Onsite, our Electricians and Technicians will be respectful and will not leave any mess behind. More so, they will never compromise on the safety of our customers, their homes, their business or the products we use.

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