Calculate Air Conditioning Sizing

Doing your own Air Conditioning Sizing for your home is very important? Most people rely on his own air-con contractor in getting the right air-conditioning units BTU capacity for them. But you are the one using the air-conditioning so you should know yourself best.

So are you the one who like to blast your air-conditioning units to the coolest? Or are you the person who feel that turning on 25-26 Degree Celsius is adequate for you?

It is important for you to know how to calculate air conditioning sizing for your air conditioner because if it is done incorrectly, you might end up buying an under-size or oversize air conditioner BTU.

An undersized air conditioner BTU will not be adequate to cool your room, or it may take a long time to cool it especially the weather now is getting warmer.

It is also not cost effective getting an over-sized air-conditioner BTU. Due to the over-sized air conditioner BTU capacity, the air-conditioner cool the room too fast which causes the compressor to cut-in (Start) and cut-out (Stop) too often.

Each time the compressor cut-in to run, the power consumption is about 6 times higher than its running current. With this cycle on and off too often it decreases the efficiency and increase your electrical bill.

It will also cause your compressor to have a shorter lifespan too. Replacing a new compressor can cost as much as SGD$900 and above depend on the size of your compressor.

Definition of BTU

The definition of BTU is the unit of measuring the quantity of heat is the British thermal unit and is the heat require to raise the temperature of 1 pound of pure water(at its greatest density) 1°F.

Calculate Air Conditioning Sizing

How do you calculate in order to get the right air conditioning sizing for your room? Please note that the method of calculate BTU mention below is just an estimation to determine the amount of air-conditioner BTU need to cool your room. Giving a consideration of 1-2 people is staying in the room.

Step 1:

Calculate the volume of the room - Length x Breadth x Height = Ans / 2 (answer divided by 2)

For example - 2.5m x 3m x 2.5m = 18.75 / 2 = 9.375

Step 2:

With the given answer (9.375). Match with the closest BTU capacity air-conditioner below with your answer which is between 9,000Btu and 12,000Btu.

List of air-conditioner BTU rating:

• 9,000Btu
• 12,000Btu
• 15,000Btu
• 18,000Btu
• 21,000Btu
• 24,000Btu

And so on...

Therefore you should get a 9,000Btu air-conditioner if you are afraid of cold and get a 12,000Btu air-conditioner if you are a person who are afraid of hot by getting a slightly bigger air-conditioning BTU.

What if you had already installed an under-size air conditioner?

Here are some methods you may want to adopt:

1) Using curtain to partition your working area.

2) Adding a fan.

3) Adding portable air-con, window air-con or casement air-con.

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