Proper Sizing For Room Air Conditioners

It is important to properly size your room air conditioner. Air conditioner sizing is all about matching the room size to the air conditioner size.

  • Air conditioners remove both heat and humidity from the air.
    • A unit that is too small will simply not cool properly
    • A unit that is oversized will provide reduced air conditioner efficiency and ineffective dehumidification.

It is important to note that if the unit is too large, it will cool the room before it has a chance to remove the humidity and will make the room feel damp and clammy.

Number 1 icon Determine your room’s square footage by multiplying the length of the room by the width of the room (in feet) and select the appropriate capacity from the chart below:

Area To Be Cooled
(square feet)
Capacity Needed
(BTUs per hour)
100 to 150 5,000
150 to 250 6,000
250 to 350 8,000
350 to 450 10,000
450 to 550 12,000
550 to 700 15,000
700 to 1,000 18,000
1,000 to 1,300 22,000
1,300 to 1,500 25,000

Number 2 icon Adjust the capacity based on the following considerations:

  • If the room is heavily shaded, reduce the capacity needed by 10 percent.
  • If the room is very sunny or has a Southern exposure, increase the capacity needed by 10 percent.
  • If you are selecting a portable air conditioner, increase the capacity needed by 1,000 BTUs.
  • If more than two people regularly occupy the room, increase the capacity needed by 600 BTUs for each additional person (For example, if 4 people regularly use the room, add 1,200 BTUs).
  • If the unit is used in a kitchen, increase the capacity needed by 4,000 BTUs.
  • If you are installing an air conditioner near the corner of a room or if there are any other obstructions, make sure that the unit you select can send the airflow in the right direction.

Number 3 icon Enjoy your Whirlpool Air Conditioner!