What Size Air Conditioner Do I Need?

Whether you’re building a new home or upgrading your existing heating and cooling system, there is one question you’re guaranteed to ponder: what size air conditioner do I need? Selecting the right AC size is a balancing act. Too large, and you could encounter poor humidity control and excessive energy expenses. Too small, and the unit might struggle to reach comfortable temperatures on scorching hot days. Appropriate air conditioner sizing is required to enjoy an efficient, cost-effective and comfortable cooling experience.

The Importance of Sizing Your Air Conditioner Correctly

Ensuring your air conditioning can generate the proper cooling capacity is a matter of comfort and keeping your energy bills low. Here’s why you shouldn’t merely guess the ideal air conditioning system size:

• Humidity control: An oversized unit cools too rapidly, preventing humidity removal and rendering your home clammy. A correctly sized air conditioner will regulate indoor humidity levels more efficiently.
• Even temperatures: A properly sized air conditioner disseminates cool air evenly and decreases unpleasant temperature fluctuations between cycles.
• Peak day performance: An undersized system will struggle to reach the target temperature on hot summer afternoons, so you need a unit large enough to keep up with cooling demand.
• Proper cycling: Air conditioners turn on and off with plenty of run time per cycle. Units that are too big for the space cycle too quickly, causing unnecessary wear and tear. Conversely, an undersized system runs continuously, which may cause overheating.
• Manageable utility bills: Cycling issues caused by selecting the wrong size of air conditioner lead to higher energy bills. However, a unit that is the proper size will function as designed and keep your utility bills in check.

Understanding Air Conditioner Size

Cooling capacity is calculated in British thermal units (BTUs). A BTU is a standard unit of energy that indicates the amount of heat an air conditioner can remove every hour. Most room air conditioning units range from 5,000 to 18,000 BTUs. Because central air conditioners are bigger, they’re usually measured in tons. A one-ton system is equivalent to 12,000 BTUs. Most central air conditioning models range from 1 to 5 tons.

Sizing a Room Air Conditioner

When examining window or portable air conditioners, sizing mainly depends on the room’s square footage. Measure the space—length x width—and match it to the appropriate BTUs:

• A room measuring 150 to 350 square feet will probably need to have a 5,000 to 8,000 BTU air conditioner.
• A room between 350 and 550 square feet should need an 8,000 to 12,000 BTU unit.
• A big room or open area of 550 to 1,000 square feet may call for a 12,000 to 18,000 BTU unit.

These general recommendations don’t consider additional factors like interior heat gain or how much sun streams in through the windows of the room. For a more exact calculation, reach out to an HVAC professional from Service Experts Heating, Air Conditioning & Plumbing.

Sizing a Central Air Conditioner

Choosing the right size of central air conditioner begins with the home’s square footage, but specific sizing requires a more in-depth look. HVAC professionals rely on load calculations outlined in Manual J to determine a home’s unique cooling requirements. Here are the considerations that technicians will examine:

• Square footage: The size of your home substantially affects its cooling requirements, with bigger homes generally requiring more cooling capacity.
• Local climate: Where you live can affect your cooling preferences as well. States with sweltering hot, humid summers naturally demand a higher cooling capacity than cooler, drier communities.
• Interior heat gain: The heat produced inside your home can come from people, lights, electronics and appliances. Additional internal heat elevates your home’s cooling needs.
• Insulation levels: The level of insulation in your walls, attic and floors affects how much heat gets inside. Well-insulated homes keep cool air more efficiently, decreasing the cooling load.
• Air infiltration rate: This refers to how much outside air enters through leaks or cracks in the building envelope. Homes with a high air infiltration requires more cooling to combat the warm, humid outdoor air that makes its way into the home.
• Home orientation and window layout: The direction your home faces determines its sun exposure, which in turn impacts your home’s cooling load. A single-family residence with very large south-facing windows absorbs more heat and calls for a bigger air conditioner than a north-facing condo.

Other Factors to Consider When Buying an AC

Besides knowing what size air conditioner you need, consider these additional factors when installing a new air conditioner:

• Brand: Not all air conditioning systems are created equal. It’s vital to buy a trusted brand for durability and longevity.
• Efficiency rating: The seasonal energy efficiency ratio (SEER) signifies the total heat an air conditioner can remove per unit of electricity it consumes. Higher SEER ratings represent higher efficiency, lowering your utility bills.
• Maintenance requirements: Regular maintenance keeps your system working correctly. Most AC manufacturers encourage yearly tune-ups to locate and repair small problems before they turn into high-priced repairs.

Get Expert Help Sizing Your Air Conditioner From Service Experts Heating, Air Conditioning & Plumbing

Finding the best air conditioner size can be overwhelming. The Experts at Service Experts Heating, Air Conditioning & Plumbing are here to help. We offer custom cooling remedies to optimize home comfort, efficiency and energy savings.

From establishing your exact cooling specifications to helping you navigate different brands and efficiency ratings, we’re there for you at every step. For help picking out the perfect air conditioner for your home in the U.S., call 866-397-3787 today to schedule your appointment with Service Experts Heating, Air Conditioning & Plumbing.