What Size Air Conditioning Unit Do You Need?

Air Conditioning units come in various sizes measured by “tons.” However, this is not based on how much they weigh, but on its ability to cool. Tonnage for an air conditioner is measured in multiples of its ability to cool 12,000 BTUs (British Thermal Units) per hour. So a 3-ton air conditioner can cool 36,000 BTUs in an hour. The BTU is a measure of energy required to cool one pound of water by one degree Fahrenheit. That means that a 2-ton air conditioner has the ability to cool 24,000 pounds of water by 1 degree Fahrenheit in 1 hour.

The question now is how does all this apply to cooling a house? How do you know what size air conditioner your home needs to cool it efficiently? Generally, air conditioning units range from 1 ton to 5 tons. Larger units are usually intended for commercial use. Often houses that might require 6 tons of air conditioning power might install two 3-ton units to cover the need.

There is a standard equation for determining the size of air conditioning unit a house requires: multiply the square footage of the house by 25, divide the result by 12,000, and subtract 0.5. The result is the approximate tonnage you need for your air conditioner. So, for example, if you have a 1,920-square-foot house, multiply 1,920 by 25 to get 48,000. Divide 48,000 by 12,000 to get 4. Subtracting 0.5 gives 3.5, which means you probably need a 3.5-ton air conditioner to efficiently cool the home. Because air conditioner sizes are usually in multiples of 0.5, you may need to round off or get the next size up to make sure of efficiency.

Having the right size air conditioner is important because modern air conditioners are designed to run in particular cycles. A large unit will cool the house faster, but because it never completes a full cycle, it will turn on and off over and over again to maintain the temperature of the house and waste a lot of energy. Matching the unit size to the space in the house allows the air conditioning system to run much more efficiently and will save in energy cost.

If you’re looking to get a new air conditioner or an upgrade, be sure to get the right sized unit. If you have any questions about choosing the right unit, be sure to contact All Day Cooling and Heating today at (239) 357-0727. Our experienced technicians can answer any questions you have about installation or upgrading, and we can make sure everything is installed correctly and running efficiently.