Sizing Up: How to Pick the Right Sized AC for Your Home

what size ac do i need

The size of your AC unit has a direct impact on how well it performs and the level of energy efficiency you’ll enjoy. It also affects how much your monthly bills are.

If you’re in the market for a replacement unit or are having a new home built, it pays to do a little research before choosing a new air conditioner. The last thing you want is to find out you’ve purchased the wrong size after it’s installed.

If you’re asking yourself, “What size AC do I need,” keep reading. We’re going over some details that will help you make an informed decision.

Understanding BTUs and AC Sizing

BTUs, which stands for British Thermal Units, refers to the amount of energy needed to either cool or heat one pound of water by exactly one degree.

The size of central air conditioners is measured in tonnage. However, in this instance, tonnage isn’t based on weight.

A one-ton AC unit can cool 12,000 BTUs an hour. Central air conditioners for residential homes are typically between 1.5 and 5 tons, depending on the size of the home. Anything over five is better suited for commercial buildings or massive homes.

If you live a home large enough to require over six tons of power, you’re better off going with two three-ton units. This way, if one unit runs into a problem, you still have another that can work to cool your home.

What Size AC Do I Need?

Now that you understand how to measure AC units in terms of power, let’s go over how to determine what size you’ll need for your specific home. This requires a little basic math, so grab your calculator.

All you’ll need to do is take the square footage of your home, multiply it by 30, divide that sum by 12,000 and subtract that by 1. The answer you get will be the tonnage you need out of an AC.

It’s important to keep in mind that if you live in a hot region of the country, you’ll be pushing your AC much harder, especially during the summer months. If this is the case, skip the last step of subtracting by one. This will give you a higher tonnage result.

Why the Size of Your AC Matters

All this may seem like overkill, especially if you’re just getting an AC for an average-sized home. However, buying the wrong size will hurt your energy efficiency.

If you’re running a unit that’s too large, it will cool your house too quickly. Instead of running through its natural cycle, the unit will turn on and off again too frequently, which will increase your monthly bill.

If you buy a unit that’s too small, it will always be running in order to keep up with your cooling demands. Again, this results in higher bills. It’s also possible that your home won’t maintain a comfortable temperature.

Find the Perfect AC Unit for Your Home

If you were asking yourself, “What size AC do I need,” use the simple formula discussed above to give you a good idea what to look for while shopping.

If you’re still unsure, try consulting an HVAC calculator or get in touch with a professional who can perform an inspection.

We provide a full range of HVAC repair and installation services in the Sugar Land area. Contact us today to learn more.