Air conditioners are available in numerous different sizes, irrespective of whether they are central air conditioners or window air conditioners. The units should be sized in a way that they cool the area of a home in which the owner wishes to cool with the most efficiency. Not many homeowners know how to do that. The good news is that by having a measurement of the area to be cooled, a homeowner can get a pretty good idea of the size of an air conditioner that is best for the room.
To calculate this, all a person has to do is multiply the length of a room by its width in order to get the area that has to be cooled. Then, the practical total number is multiplied by 25 BTU. This makes ample cooling possible whether on a moist rainy day or a sunny humid hot day. For instance, a room that measures 15 feet long and 12 feet wide. When multiplied, they bring a total of 180 square feet. By multiplying the 180 square feet with 25 BTU per square foot, one gets an idea of the minimum BTU of the air conditioner that he or she should buy. 180 * 25 add up to 4500 BTU, which is the cooling capacity needed.
A potential buyer may wonder if small air conditioners can work or it would be better to get a larger one. Lesser BTU units will run continuously in order to try and keep up. This increases the electricity bill, while it is unlikely that the air conditioners will cool the entire area effectively.
An air conditioner that is too large is likely to be overkill. To dispel the misconception that bigger is better, air conditioners that are too large can cool more rapidly. However, this is likely to impede why the units are being run in the first place. In addition to cooling the air, air conditioners also extract humidity (moisture from the air) that make occupants of a room feel hot and sticky. Despite the air being cooler, it is not possible to properly extract moisture from the air. It would be similar to camping outside on a clammy, cool foggy night. Many people are familiar with the feeling of moist skin and the Goosebumps gotten when cold air flows over it. Additionally, an air conditioner that is too large will frequently cycle on and off.
Many homeowners purchase too large air conditioners thinking that it will offer better cooling. In the real sense, an oversized unit is less effective and also wastes energy in the process. While it will cool the area rapidly, it will only remove some moisture but not all of it. A unit that is properly sized will effectively remove humidity in the course of the cooling process.
A homeowner should themselves favor and measure the area of the room to be cooled and then calculate the BTUs needed. Once this is done, he or she can properly size the air conditioner.