The size of the a/c machines doesn’t refer to the physical dimensions of the a/c unit.
- Instead, it refers to its cooling capacity measured in British Thermal Units (BTUs).
Whether you intend to install a central air machine or a window a/c unit, you will achieve optimum efficiency. Therefore, lower utility costs if you choose your a/c machine based on the size of your residence or the area your machine must cool. To choose what a/c machine size is appropriate for your residence, first, you will need to calculate the size of your home’s areas that the a/c machine will serve in square feet. To calculate the size, multiply the width times the length of the area to be cooled. The total results are then multiplied by 25 BTU, which is a practical number. This size will supply ample cooling under any climatic condition, be it a rainy, hot, sunny, moist, or humid day. Given a room that is 12 feet wide by 15 feet long for example, you will multiply the length by the width 12×15 to get 180 Square feet. The 180 square feet will then be multiplied by the 25 BTU per square foot to get you the minimum BTU a/c machine you should install. This means 180 × 25 = 4,500 BTU cooling capacity is definitely needed for your space. While smaller BTU machines will run continuously to keep up with your temperature requirements, too many units will cool too hastily but won’t actually pull any moisture from the air.