How Do I Know If My A/C Unit Is Big Enough?


Only the correct size of an air conditioning unit will effectively keep you and your family comfortable. An A/C that is too big will not only consume a lot of your power but will also leave your house with excess humidity. On the other hand, an A/C that is too small will not cool your room or house to the desired temperatures. Accordingly, choosing the right sized air conditioner require a little bit research and some basic mathematics. Here is an overview of a few tips that you can use to end up with the right A/C for your home:

1. Measure the Square Footage of Your Room: Using a tape measure, measure the length and width of the room that you plan to air condition. If the room is not rectangular or square, you can divide it into smaller sections (composed of triangles and squares) so that you take the measurements.

2. Calculate the square footage of your room. You can do this by multiplying the length of your room by its width if your room is square or rectangular. For a room with other shapes, you can divide it into triangular sections, which you can then find their square footage by multiplying 0.5 by length by width then summing them up. The sum will be the square footage of the room.

3. If you are planning to purchase a central A/C system, calculate the square footage of every room in your home. Don’t include areas such as basements or garage because they won’t be cooled.

4. Determine the cooling capacity of your room or your home. The cooling capacity of a central or room air conditioner is usually measured in British Thermal Units (BTUs) per hour. Depending on the size of your room or home (in square feet), you will easily gauge its cooling capacity from the United States Department of Energy Star website—they offer guidelines for BTUs per square feet.

For better performance, buying the right size of an AC should be a priority. Follow our blog for more information on heating, cooling, and keeping your home energy efficient.

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