Sizing Guide
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Sizing Air Conditioners
   Area To Be Cooled (square feet)   Capacity Needed (BTUs per hour)
 100 up to 150   5,000
 150 up to 250   6,000
 250 up to 300   7,000
 300 up to 350   8,000
 350 up to 400   9,000
 400 up to 450   10,000
 450 up to 550   12,000
 550 up to 700   14,000
 700 up to 1,000   18,000
 1,000 up to 1,200   21,000
 1,200 up to 1,400   23,000
 1,400 up to 1,500   24,000
 1,500 up to 2,000   30,000
 2,000 up to 2,500   34,000 
2. Make any adjustments for the following circumstances:
 • If the room is heavily shaded, reduce capacity by 10 percent.
 • If the room is very sunny, increase capacity by 10 percent.
 • 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.
 • Consider where you install the unit. If you are mounting an air conditioner near the corner 
 of a room, look for a unit that can send the airfl ow in the right direction.
 100 up to 150   5,000
 150 up to 250   6,000
 250 up to 300   7,000
 300 up to 350   8,000
 350 up to 400   9,000
 400 up to 450   10,000
 450 up to 550   12,000
 550 up to 700   14,000
 700 up to 1,000   18,000
 1,000 up to 1,200   21,000
 1,200 up to 1,400   23,000
 1,400 up to 1,500   24,000
 1,500 up to 2,000   30,000
 2,000 up to 2,500   34,000 
Area To Be Cooled (square feet)   Capacity Needed (BTUs per hour)
 100 up to 150   5,000
 150 up to 250   6,000
 250 up to 300   7,000
 300 up to 350   8,000
 350 up to 400   9,000
 400 up to 450   10,000
 450 up to 550   12,000
 550 up to 700   14,000
 700 up to 1,000   18,000
 1,000 up to 1,200   21,000
 1,200 up to 1,400   23,000
 1,400 up to 1,500   24,000
 1,500 up to 2,000   30,000
 2,000 up to 2,500   34,000 
1. Use the chart below to estimate the BTU requirement for the area you wish to cool.

