Buying the Right-Size Air Conditioner

It does not mean that if you buy a bigger air condition, it is going to give you more comfort. If the unit is too large, most of the time it will wastes a lot of energy and as for a unit which is too small sometimes it does not accomplish the task of providing a cool environment to your room. Before purchasing an air conditioner, it is important for you to determine the right-size of unit suitable for your room. Below are some of the information which is useful in determining the correct unit for your house.

What you need:

  1. Determine which room to install the air condition
  2. Measure the room size accordingly (use the rule of thumb formula)
  3. Take into account the room\’s characteristic


  1. Firstly, you have to determine which room you are going to install the air conditioner before deciding to purchase the air condition system.
  2. Get the correct size of your room\’s square footage by measuring it correctly. Bear in mind that if you just guess the size of the room, you will end up buying a too weak or too powerful unit.
  3. In order to calculate the size of your air conditioner, you can use the rule-of-thumb formula as stated below:
  • For room size ranging from 100 to 250 square feet, use a 5000-6000 BTU (British Thermal Units) size of air conditioner;
  • For room size ranging from 400 to 550 square feet, use a 8000-11000 BTU size of air conditioner;
  • For room size ranging from 550 to 875 square feet, use an 11000-15000 BTU size of air conditioner.
  1. You also need to take into consideration the room\’s characteristics. For example, if the room has high ceilings and receive lots of sun exposure, you definitely need a powerful unit. Apart from that, other factors also need to be taken into account such as the room\’s sunlight, its airflow, the number of people occupying the room, plus its room temperature.
  2. You also need to determine which of your room walls is the most exposed to the outside elements whether it is facing east, north, south or west. You can set the four location with values such as 17 for the east, 20 (west), 16 (north) and 18 (south). This method enables you to use the volume of the room and multiply that number against the corresponding number for whatever direction you have chosen.

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