Why Size Matters When Choosing Your AC Unit

All AC units are created equally, right? Actually, no. When it comes to your home’s AC unit, choosing the correct size is absolutely essential to ensuring that it runs properly and keeps the temperatures from soaring inside your home during the hotter months. If your unit is too small or too large, it not only costs more money to run but also won’t keep your home comfortable. Before choosing the wrong size AC unit, read our blog to learn what will fit your home best.

How AC Size Affects Performance

Selecting an incorrectly sized AC unit has many consequences.


If your air conditioner is too small, it won’t be able to cool your home adequately and will run in longer cycles to compensate for the area being too large. If your unit is too large, on the other hand, it will run in short cycles, turning off and on in quick bursts that bring your home’s temperature down too fast. This prevents your home from being effectively dehumidified, causing inhabitants to feel clammy. Even worse, the short bursts can contribute to mold and fungus growth.


Air conditioners that are insufficiently sized run longer trying to keep your house at your set temperature, stressing your unit leading to premature breakdown and malfunctioning. Similarly, units that are too big run in shorter cycles, wasting energy, putting undue wear and tear on the unit, and causing it to burn out quickly.


An incorrectly sized AC unit costs you more money to run and will require more maintenance and repair over its shortened life than one that is perfectly sized for your home. An oversized AC unit will also cost you more upfront.

Indoor Air Quality

Another issue with having an oversized AC unit is that it negatively affects your indoor air quality. When your unit runs in shorter bursts, it’s unable to filter the air like a properly sized unit could. Insufficient filtering prevents your AC from effectively removing your home’s indoor air pollutants such as dust mites, mold, pet dander, allergens, and skin cells.

Determining the Correct AC Size

Choosing the proper sized AC unit depends on your home’s square footage as well as factors such as roof slope, ceiling height, number of rooms and windows, and insulation.

When considering how big your home’s AC unit should be, its size doesn’t refer to its physical measurements but rather how much heat it can remove per hour in tons. Your AC’s cooling capacity is measured in British Thermal Units (BTUs), and 1 ton of refrigeration equals 12,000 BTUs.

Because our North Central Florida climate is hot and humid, the general rule of thumb is 30 BTUs per square foot. If your home is 2000 square feet, you could calculate your AC size by multiplying that number by 30 to get 60,000. Then you divide that number by 12,000 to learn that you need a 5 ton AC unit.

Comfort Temp Helps You Choose the Perfect AC

Comfort Temp has spent over 35 years keeping homes in Gainesville and the surrounding communities comfortable. When it comes time to install a new AC or replace your existing unit, trust our experienced team to guide you on picking the perfect size that will keep your home temperature how you want it while also saving you money on your utility bills — and preserving the life of your unit. Reach out to us today to schedule an appointment.

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