Air Conditioner Sizing Tutorial.
How much air conditioner BTU's I need?

Picking the right home air conditioner is very easy with the right information. Before buying an air conditioner, find out how many BTUs you need.  This means think of the size of the room, and what the room will be used for. Matching Btu requirements to room size is very important when you buying an air conditioner system.

This air conditioner sizing tutorial will explain you how to choose the right air conditioner size. Choosing an air conditioner size that is too small (low BTU rating) for the intended room will leave you feeling hot and flustered! And buying an air conditioner that is too big for the room can have its problems too. So the main question is what does BTU mean?

BtuBritish Thermal Unit (Btu) is the international measure of energy. A Btu is the amount of heat needed to raise 1 (one) pound of water by 1(one) degree Fahrenheit. In HVAC industry, Btu's measure the quantity of heat a conditioning unit can remove from a room per hours. One BTU per hour is equal to 0293 watts. As the Btu rating increases, so does the weight, size and cost of the air conditioner.
To calculate how many BTU’s you need you can use this table.

Room Size Square Footage Recommended BTU Range
10'X15' 150 Up to 5400
10'X20' 200 6000
17'X20' 340 8000
20'X20' 400 9000
18'X25' 450 10000
22'X25' 550 12000
25'X30' 750 14500
25'X34' 850 16000
25'X40' 1000 18000
35'X40' 1400 24000
38'X40' 1520 28500
40'X40' 1600 32000


The following tables are estimates based on average room conditions in a moderate climate. 

Exceptions are Kitchens – add 4,000 BTU cooling capacity to the recommended size.
High Ceilings/Unusual Floor Plans
– increase BTU by 10%.
Warmer Climates – may require 10-20% additional BTUs per room over regular amount.

BTU size too large:
A conditioner that has a bigger BTU rating than the room size needs will cycle off too quickly. The unit will not remove the humidity from the air properly.

Air Conditioner size too small:
A conditioner that has a smaller BTU rating than the room requires will run continuously. The unit will not cool the room adequately.

NorthCool home air conditioner systems are normally 9,000 – 24,000 Btu's.
This BTU rating provides sifficient cooling capacity for any home, condo or loft.
If you have any questions please contact NorthCool's distributor near you