Air conditioners cool the air while removing heat and humidity from the interior of the home or flat. Once you have made that all-important decision to add an air conditioning system, selecting the proper type and size is the difference between cooling to a proper level and experiencing the frustration of having an air conditioning unit that does not fit your needs.
Air Conditioning System Capacity
British thermal units (BTUs) are the standard for measuring air conditioning capacity. A small window air conditioner can deliver as few as 3,000 BTU, where a wall unit can exceed 20,000 BTUs. When considering the size of the unit you should consider the number of windows, room exposure, quality of insulation, and the power drawn by other appliances. You can use a BTU calculator to determine the correct size unit to purchase.
Portable Air Conditioning Units
Versatile and designed for ease of movement, portable air conditioning units, which are especially ideal for windowless spaces, vent exhaust through temporary ducting and you can easily move them from room to room as needed. As is the case with portable heaters and fans, you need to take care to keep cords secured if you have children or pets. Portable air conditioners combined with a ceiling fan can cool an average size room.
Window Air Conditioning Units
Window air conditioning units are arguably the most popular type of air conditioners. The unit sits on the sill of a window opening and vents warm air to the outside of the home while pushing cooler air into the room. For DIY installations, these units are the easiest to install and remove. Purchasing a window or portable unit that does not have enough BTUs to cool a room is common, so be sure to measure and purchase carefully for each room.
Wall Air Conditioning Units
Wall units install in an outside wall and are heavier and more difficult to install than window units are. Because these units tend to use greater amperage and voltage, they may need professional installation and an electrician to review the circuitry and approve the installation. The unit rests within a weight supporting air conditioner sleeve set into a wall, so it may be difficult to install a wall unit in a brick or stone wall.
Entire Home Air Conditioning System
Central, forced air, or entire home air conditioning units cool the entire home at once. Often combined with heating with the use of a heat pump or heating unit to create a complete heating, ventilation, and air conditioning unit, they are the most expensive of all the options. These units typically require expert installation, including electrical and plumbing work.