How Do Window Air Conditioners Work?

Last Updated: 9/16/2023 and reviewed by our team of HVAC professionals 

Is your home feeling a little less than comfy this summer? If yes, you might be wondering, how do window air conditioners work? Would a window unit be the right choice for your home? Let’s take a look at how a window AC unit works and if it’s something you can take advantage of this summer.

What is a window air conditioner?

A window air conditioner is the simplest type of AC unit. It’s a single unit with all of the parts and components contained inside one box or casing. This type of AC is usually mounted or installed in a window and plugs into a traditional electrical outlet. It’s convenient because it can be moved from window to window as needed and operates independently from a home HVAC system.

How does a window unit work?

A window AC unit uses the same principles as any other type of air conditioning system. It uses refrigeration properties to remove heat and humidity from a room while cooling air circulates into the room. The basic components include a thermostat, a fan or blower, tubing filled with refrigerant, a compressor, an evaporator coil, and a condenser coil.

As the temperature in the room rises, it triggers the thermostat in the AC unit, which turns on the blower. Room air is pulled into the unit and moves over the cold refrigerant coils. The air is cooled as it passes over the cold coils and is pushed out into the room, cooling it and bringing down the temperature.

How do you pick the right window AC unit for your home?

The primary consideration when choosing a window AC unit is size. If it’s too small, it will have to work overtime to cool the room and you’ll still have a room that doesn’t quite feel cool enough. If it’s too big, it will cool the room too quickly without removing the humidity properly and you will have a cool room that still feels sticky.

Take a look at the square footage of the room you want to cool using a window unit. Generally speaking, a window AC needs 20 BTU (British Thermal Units, a measurement of cooling capacity) to cool one square foot of space.

To Measure What Size Window AC Unit Is Needed For Your Room?

Multiply the length of the room by the width and then multiply that number by 20. That should give you the BTUs you need to cool that space. Be careful when you choose what window to put the unit in. There are other factors such as window size, location within the room, and exposure to the elements that can impact its effectiveness. Take a look at how the weather can have an impact.

If your house is just too darn hot and you need to cool it independently or give your HVAC system a boost, you might want to consider adding a window AC unit, if you'd like to get your current AC unit repaired or a new AC unit installed contact the team at Aire Serv Heating and Air Conditioning for help choosing the right one for your budget, square footage, and cooling needs.