How big should my air conditioner be?

Equipment size is very important when air conditioning a space. Bigger is not necessarily better. The correct sized air conditioner will save considerably on energy use and installation and running costs. 

A feeling of comfort is achieved by choosing the correct size for the space.  There is a ‘rule of thumb’ formula that can be used as a guide, however we do suggest that you discuss your requirements with our experienced staff.  .

To calculate Air Conditioner size to allow for ample cooling (whether it is a rainy, moist day or a hot, sunny, humid day), this simple formula works for a given room in a domestic environment

           Length (m) x Width (m) x 173.446 = Watts required

If the area to be cooled includes a kitchen , add an extra 2000 Watts.

(Convert Watts to BTUs by multiplying Watts x 3.412 = BTUs)

 

Other items to consider are:

• How large are the rooms and what shape are they?
• What the building is made of and how well insulated is it? 
• How many people use the room? 
• What is the ceiling height? 
• Positioning and size of windows?
• For room air conditioners, what direction (north, east, south or west) does the room face? 
• What time of day the room is most likely to be in use (night or day)?

Do not make the mistake of choosing an air conditioner that is:

• Too small as it will likely run continually and increase your bill and not cool effectively
• Too big as it may cool the area but will not run long enough to extract moisture from the air properly. It will also turn on and off frequently.

It is well worth measuring the area to be cooled and choose the correct size of air conditioner. We at Harle’s Electrical can assist with any advice that you require in order to select the proper air conditioning size for your home.

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