When purchasing a new air conditioning unit, there are several factors to take into consideration. You should make sure to identify your needs, measure your space, and think about the sort of use you plan to give your AC unit.

Specifically, you'll need to consider the following:

Cooling Capacity:

The ability of each AC unit to cool a specified area is measured in BTUs. Higher BTUs indicate greater cooling power, however, it is not smart to choose a unit simply based upon its cooling capacity. The size of the room you wish to cool will play prominently into this decision. If you choose a unit with a BTU that is too high for the space, the air conditioning unit won't operate efficiently, may cycle on and off too often, and will cost you extra every month on your energy bill.

Energy Efficiency:

A unit's EER rating stands for its Energy Efficiency Rating. EER is derived by taking a unit's BTU rating and dividing it by its wattage. The higher the EER, the more efficient the model is and the lower your energy bills will be. For comparison, an air conditioning unit with an EER of 10 will use about 20% less energy than a unit with an EER rating of 8.

Installation Requirements:

Make sure that the unit you are considering purchasing is the right size for the window you plan to use it in. Some units also require special wiring, so be aware of any special requirements.

Air Conditioner Type:

You'll need to decide whether or not you'd like to purchase a window AC unit, which is mounted in a window frame, or a portable AC unit, which can be moved from room to room. If your cooling needs change and you sometimes need to cool down different rooms, you might consider a portable AC unit.

Wall units are also an option. Wall unit air conditioners are designed to be mounted in holes cut into exterior walls. Some prefer wall units because they do not take up window space and don't leave your home as vulnerable to burglars. Wall units generally require a great deal more effort for installation than similar window units.