What Size Window Air Conditioner Do I Need?

Hello everyone and welcome to RefrigerantHQ! Over the past few days we have been focusing on anything and everything there is to do with window air conditioners. When we do a series of articles like this on products we do tons of research to make sure that not only do we understand the poducts but also that we are giving you truthful information.

Through out our research on these products a common question that has come up again and again is what size window air conditioner do I need? Should I get the lowest BTU that I can find? What in the world is a BTU in the first place? While most people may think that buying a window air conditioner is as simple as going to a retail store or buying one on Amazon there is in fact a lot of leg work and determinations that have to be done before a purchase should be made.

Room Size

The first thing that you need to ask yourself is what room am I aiming to cool with this new air conditioner? Is it a small office in a detached garage? Is it a medium sized bedroom, or a larger master bedroom? Are you looking to cool just that room or other rooms along with it? Perhaps the entire floor or home itself? Once you have determined your requirements of what needs cooled the next step is to measure the square footage of your room. This is easily done by measuring the width and the length of the room. When you have both numbers all you need to do is multiply them together to get your square footage. As an example if we take a twelve by ten room we get a square footage of one-hundred and twenty.

Now that we have an idea of how much square feet we will be cooling the next step is to determine the power that you need to cool this square footage. To understand the power that you will need you have to understand BTUs, or British Thermal Units. BTUs are the traditional measurement unit of heat.  In the air conditioning world BTUs are a measurement of the cooling capacity of your window air conditioner. The bigger the number of BTUs the more powerful and the higher cooling capacity of your A/C unit.  As a standard measurement an air conditioner needs around thirty BTUs for each square foot of living space that you wish to cool.

Window Size

We all know that old rule, measure twice and cut once. Well the same rule applies to air conditioners. Always always always be sure to measure the width and the height of your window to ensure that the air conditioner that you will be buying will fit and will fit correctly. To get even more specific you may even take into consideration the depth of your new AC unit and see if there are any trees, shrubs, or anything else that could obstruct exhaust flow of your unit. Remember folks, that heat has to go somewhere and if there is something obstructing your exhaust your air conditioner isn’t going to have a good time.

As I said before it is best for you to measure the window so you know exactly what you are dealing with but I will give you this bit of advice. Most windows found in homes today range between twenty-four to thirty inches wide and forty-eight to fifty-six inches high. If you are unsure of the dimensions of the air conditioner you are wishing to buy either on Amazon or the manufacturer’s official product page will have the full details for you.

Find the highest-rate ones on Amazon.com now


While this article gave us a short overview of what to look for when purchasing an air conditioner I would like to refer anyone who is truly serious in purchasing a new window unit to visit our in-depth article on exactly what to look for, what room sizes fit what BTUs, what outlets to use, and anything and everything else having to do with purchasing a new window unit.