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Buying an Air Conditioner

First of all, it's good to know that air conditioners have 3 functions:
- to lower the temperature,
- to remove the humidity (moisture),
- and to filter the air. To choose the air conditioner that will perform its purpose efficiently in a certain area, several decisions have to be made before deciding on the right one for you.


Window units are the most popular as the most efficient, reasonably priced, and easy to install. These are constructed for the windows that slide up or to the side so they would be placed in the gap when the window is opened, easy to be installed in the spring, and removed in the fall.
Portable air conditioners do not need to be mounted in a window, so they are perfect for a room with no windows or only one window that you don’t want to block. They are usually on wheels and are vented through a hose placed in a window.
Wall units require a sleeve to be properly installed and are placed in holes cut into exterior walls. For this appliance, a contractor is needed to properly cut a hole into the wall and install the air conditioner.

Mini-Split air conditioners are a system with a separate interior and an outdoor unit. These air conditioners can control the temperature up to eight rooms depending on the compressor.

Unit Size

Measuring a unit size is important when it comes to any type of air conditioner. Make sure the unit is the right size for your window or wall opening.

Room Size

An air conditioner must have the right cooling capacity for the space. A unit with too high a cooling capacity can turn off and on too often. Many factors impact the power level necessary:
- Height of the ceiling
- Number of windows in the room
- Is the room on the top floor?
- Are there many open doorways leading into the room
- Is the window or wall unit going to be placed in direct sunlight
- A room with computers or even a mini-fridge might require a more powerful machine.


British Thermal Unit is a measurement that indicates how much heat the air conditioner can remove over an hour. To measure how many BTUs your area needs, you need to calculate the square feet of the floor, the ceiling height, and various other issues. Generally, an air conditioner needs about 20 BTU per square foot of space. Multiply the length of the room by the height to get the number of square feet. Add in the size of any attached rooms that are not separated by doors.

Smart Features

There are also some additional smart features implemented into more high-end smart models like built-in WiFi, Google Home and Amazon Alexa and more.