Smallest Portable Air Conditioners

Unit Size

• The smallest width for portable air conditioners is about 12 inches. Larger units can be as wide as 21 inches. The smallest depth is about 14 inches, compared with a depth of about 26 inches for larger units. The shortest units are less than 30 inches tall. Larger units can be 44 inches tall. Smaller units take up about half the space of large units, making them suitable for even the smallest rooms.

BTU Capacity

• Smaller portable units have a maximum BTU capacity of 12,000 and a minimum capacity of 5,000. This is much less than the BTU capacity of larger units, which typically start at 10,000 BTUs and go as high as 60,000 BTUs. The BTU capacity determines how much heat the portable air conditioner can move and cool in one hour.

Cooling Capabilities

• The smaller the room, the less BTU capacity you will need. A portable air conditioner with a BTU capacity of 10,000 is appropriate for spaces of 350 to 450 square feet. A unit with a BTU capacity of 5,000 will accommodate a room that's 100 to 150 square feet. To calculate square feet, multiply the length of the room by the width of the room. For example, a room that is 20 feet long and 18 feet wide would have 360 square feet. Therefore, a portable air conditioner with a 10,000 BTU capacity would be the right size for this room.

Smaller Use of Electricity

• As a rule, the smaller the portable air conditioner, the less electricity it will use. For example, a unit with a width of 12 inches, a depth of 14 inches and a height of 34 inches may use only 850 watts of electric power, while a unit that's about twice that size might use as much as 1,400 watts.

Costs

• Portable air conditioners typically cost more than window air conditioners. Prices for portable air conditioners with a 5,000 BTU capacity start around $290, and those with a 10,000 BTU capacity start around $425. This is substantially lower than large models, which can cost thousands of dollars. For example, a unit with a 13,780-BTU capacity can cost more than $3,000.