Choosing The Right Size Room Air Conditioner

The most important thing to consider when purchasing an air conditioner for a single room is the size of the unit. If the unit is too small, it will struggle to keep the room at the desired temperature. If the unit is too big, it will use up valuable energy and put out excess humidity. The perfect-sized air conditioner will leave you comfortable and save you money!

Single room air conditioners normally have cooling capacities ranging from 5,000 to 12,500 British Thermal Units (BTUs). Typically, an air conditioner needs 20BTU for each square foot of space. However, there are some considerations you need to take into place when making your decision.

First, you need to determine the room’s exact square footage.

For square and rectangular rooms:
– Multiply the full length of the room by its width

For triangular rooms:
– Multiply the length of the area by the width and divide by two

For complex-shaped rooms:
– Divide the room into squares, rectangles and triangles. Then use the formulas above to determine the total square footage.

Next, you can use the chart below to determine the general capacity your unit should be rated for:
Area to be cooled (square feet)
100-150
150-250
250-300
300-350
350-400
400-450
450-550
550-700
700-1000
1000-1200
1200-1400
1400-1500
1500-2000
2000-2500
Capacity (BTU’s)
5000
6000
7000
8000
9000
10000
12000
14000
18000
21000
23000
24000
30000
34000
Finally, you should increase or decrease your unit’s capacity rating(found in the chart above) by taking into account the following variables:

• If the room is normally shaded, reduce capacity by 10 percent.
• If the room is normally sunny, increase capacity by 10 percent.
• If more than two people normally occupy the room, add 600 BTUs for each additional person.

Sometimes there can be unique variables to consider in relation to the build of the home when you’re trying to calculate the perfect air conditioning unit for your room(s). If you’re still in doubt and you have additional questions, please contact your local air conditioner experts at Charlotte Comfort Systems today!