08/29/2018
Air Conditioner Cooling Needs Calculator
To determine the correct size of Air Conditioner for your room, follow these easy steps:
1. Determine the square footage of the area being cooled.
2. Using the square footage and the chart below, determine the correct cooling capacity.
Cooling capacity is measured in British thermal units (BTUs) per hour.
3. Make any adjustments to the following circumstances:
● If the room is heavily shaded, reduce capacity by 10 %.
● If the room is very sunny, increase capacity by 10 %.
● If more than two people regularly occupy the room, add 600 BTUs for each additional
person.
● If the unit is used in a kitchen, increase capacity by 4,000 BTUs.
● For the purpose of this chart, rooms that are connected by permanently open entryways
wider than five feet ought to be considered as one room and their square footage should be
combined.
The area to be Cooled
(Square Feet)
Capacity Needed
(BTUs per Hour)
100 to 150 5,000
150 to 250 6,000
250 to 300 7,000
300 to 350 8,000
350 to 400 9,000
400 to 450 10,000
450 to 550 12,000
550 to 700 14,00
700 to 1000 18,000
1000 to 1200 21,000