Why Does AC Size Matter?

Bigger isn’t always better. Smaller doesn’t mean more savings.

There is nothing more inconvenient than your AC breaking down in the middle of a hot Orlando summer. If this is your first time purchasing and installing a new air conditioner, you’re probably wondering: Which AC brand is better? Should I get one with a higher SEER rating? Is a variable speed AC worth it?

What if we told you none of that actually matters? At least, not as much as you think.

The most important factor to consider in a new central AC system is its size relative to the size of your home, plus other factors such as outdoor climate, how well your home is insulated, and the number of rooms and windows you have.

A properly sized unit has a greater chance of providing you with long-term peace of mind:

Better cooling efficiency

  • Better indoor comfort

  • Less risk of breaking down

  • More reasonable energy costs

Sizing an AC Unit for Orlando Residents

When searching for the right AC size, you will look at tonnage. This does not refer to how heavy the unit weighs! Ton in this case refers to cooling capacity.

  • An air conditioner’s capacity to cool is measured in BTUs (British Thermal Units)

  • One ton of refrigeration equals 12,000 BTUs


Standard rule is 20 BTU per square footage. However, since Orlando is located in a hot and humid zone, we are more likely looking at 30 BTU per square foot.

For example, if you live in a 1,200 square foot home, you would calculate your AC size like this:

1,200 x 30 = 36,000 BTU → 36,000 / 12,000 = 3 tons

So the ideal AC would be a 3-ton unit for a 1, 200 square foot home.

Try it out with your own home and discuss the results when you speak with your Orlando AC installer


What Happens if Your AC is Too Big or Too Small?


Too big: Your AC will frequently cycle on and off, which can lead to a premature system breakdown. It will also be less efficient at removing humidity in your home.


Too small: Your AC will run for longer cycles, which puts a strain on the compressor. A too-small unit will be overworked and won’t have enough power to provide a comfortable level of cooling. 


In both cases, you may constantly find yourself calling for emergency AC repair. This is because your improperly sized unit is straining itself as it tries to work harder to meet your home’s cooling demands—resulting in an exhausted system that will burn out before its time.  


Enjoy Hassle-Free Cooling


You can buy the best AC brand out there, but if the unit isn’t sized properly and is poorly installed, you will quickly experience problems. 

Almost as important as choosing the right AC size is choosing the right AC contractor to install it for you. A reputable contractor will always perform a Manual J load calculation, which involves looking at several elements of your home to arrive at the correct AC size. Duct sizing calculations will also be carried out to make sure your existing air ducts are compatible with your new AC unit. 

Working with a licensed Orlando AC installation expert ensures higher quality workmanship and compliance with Florida code—leading to greater peace of mind for you and your household.


4 Seasons Air Conditioning & Heating, Inc. is one of the most trusted AC companies in Orlando. Give us a call at 407-295-9231 to discuss your options for new AC installation!