Portable Air Conditioner Sizing - How Important is It?

To stay cool when it is impractical, impossible or cost prohibitive to install a traditional air conditioning unit, some people use portable air conditioners. They are maneuverable and easy to install. In fact they don't even need to be permanently installed. They just need to be vented. Portable air conditioners are perfect for people who want cooling without having to give up window space. They are more convenient than window air conditioners and are simple to operate. Most have wheels or casters on the bottom that make them easy to move from one part of your home to another. Money is saved because only the area you need is cooled. They can act as a fan when there is less need for cooling and sometimes a heater function is included so that it can be used all year long.

Portable air conditioners have simple configurations. There is a box-like design that holds the cold and hot sides in one. An exhaust hose expels the heat and water is condensed out of the air. The resulting water is collected in an internal drain bucket or through a drain hose. Some portable air conditioners use evaporative technology so that little to no water is produced.

One of the most important factors to consider when choosing a portable air conditioner is the BTU rating. BTU stands for British thermal unit, which is a unit of energy used in power, steam generation and heating and air conditioning industries. BTU rating describes power and cooling capacities. It measures the heat that an air conditioner can remove from a room. The higher the value, the stronger the air conditioner. BTU ratings usually range from 5,000 to 30,000 and the size needed depends on the area being cooled.

Your portable air conditioner's cooling efficiency can be affected by the wrong BTU value. If there is a higher value that the corresponding room size the unit will cycle on and off too quickly and will not properly remove humidity from the air. When it cycles on an off like that, energy is wasted, electric bills are increased and the unit is strained. Also, there is a chance that the unit can freeze over but many units come with an automatic shut-off switch that operates when the unit gets too cold. If the BTU rating is lower than the corresponding room size, the room will not be adequately cooled

Portable air conditioners only work properly when appropriately sized so keep these simple steps in mind when choosing a unit:

- Measure the room dimensions by multiplying the length by the width. You'll need about 30 BTUs per square foot of space.

- Verify the size of the window opening.

- For each person over two in a room add 600 BTUs. Each person at rest adds approximately 230 BTUs to a room per hour.

- For kitchen cooling or other rooms with a lot of heat add 4,000 BTUs. Also, if you live in a very warm climates you'll probably need a portable air conditioner that outputs more BTUs per hour