When the temperature outside begins to climb, many people seek the cool comfort of indoor air conditioning. One type that we see all the time is the window air conditioner. Window air conditioners are an easy and economical way to cool a small area. Air conditioners come in various sizes, cooling capacities and prices. Most businesses and office buildings have condensing units on their roofs.

Air conditioners are one of those things that we see every day but seldom pay much attention to. An air conditioner is basically a refrigerator without the insulated box. It uses the evaporation of a refrigerant, like Freon, to provide cooling.

Air conditioners remove both heat and humidity from the air. If the unit is too large, it will cool the room quickly, but only remove some of the humidity. This leaves the room with a damp, clammy feeling. A properly sized unit will remove humidity effectively as it cools.

Room air conditioners are rated by their energy efficiency ratio EER, which is the cooling output divided by the power consumption. The higher the EER, the more efficient the air conditioner.

Portable air conditioners are not as effective as window ac units yet, and only recommend these when a window unit does not fit into a window such as casement or slide-out styles. Many people buy an air conditioner that is too large, thinking it will provider better cooling. However, an oversized air conditioner is actually less effective - and wastes energy at the same time.