What Size Air Conditioner Do I Need?

Whether you’re building a new home or updating your existing HVAC system, there is one question you’re guaranteed to ask: what size air conditioner do I need? Choosing the right air conditioning size is a balancing act. Too large, and you could encounter poor humidity control and significant energy expenses. Too small, and the unit might fail to provide comfortable temperatures on extremely hot days. Appropriate air conditioner sizing is crucial to enjoy an efficient, cost-effective and comfortable cooling experience.

The Importance of Sizing Your Air Conditioner Correctly

Ensuring your AC produces the perfect cooling capacity is a matter of comfort and cost savings. Here’s why you shouldn’t just guess the correct air conditioner size:

Humidity control: An oversized unit cools too fast, reducing humidity removal and making your home clammy. A correctly sized air conditioner will manage indoor humidity levels more successfully.
Even temperatures: A properly sized air conditioner disseminates cool air evenly and decreases irritating temperature variations between cycles.
Peak day performance: Systems that don’t have enough cooling capacity struggle to get your home to the target temperature on hot summer afternoons, so you need a unit powerful enough to keep up with cooling demand.
Proper cycling: Air conditioners power on and off with sufficient run time for each cycle. Units that are too large cycle too quickly, causing unnecessary wear and tear. Then again, an undersized system runs continuously, which may cause the unit to become overheated.
Manageable utility bills: Cycling problems caused by selecting the wrong size of air conditioner result in higher energy bills. However, a unit that is the recommended size will operate effectively and keep your utility bills in check.

Understanding Air Conditioner Size

Cooling capacity is expressed in British thermal units (BTUs). A BTU is a standard unit of energy that indicates the amount of heat an air conditioner can remove per hour. A large percentage of room air conditioners range from 5,000 to 18,000 BTUs. Because central air conditioners are more powerful, they’re commonly measured in tons. A one-ton system is proportionate to 12,000 BTUs. Many central AC units range from 1 to 5 tons.

Sizing a Room Air Conditioner

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

A room measuring 150 to 350 square feet might need a 5,000 to 8,000 BTU air conditioner.
A room measuring between 350 and 550 square feet may need an 8,000 to 12,000 BTU unit.
A spacious room or open area of 550 to 1,000 square feet may necessitate a 12,000 to 18,000 BTU unit.

These general tips don’t take into account factors like interior heat gain or how much sun streams in through the windows of the room. For a more precise calculation, contact a cooling specialist at Service Experts Heating, Air Conditioning & Plumbing.

Sizing a Central Air Conditioner

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

Square footage: The size of your home substantially affects its AC requirements, with more sizeable homes generally requiring more cooling capacity.
Local climate: Where you live can affect your cooling needs as well. Areas with sweltering hot, humid summers normally demand a higher cooling capacity than cooler, drier communities.
Interior heat gain: The heat created inside your home can come from people, lights, electronics and appliances. Higher internal heat increases your home’s cooling demands.
Insulation levels: The amount of insulation in your walls, attic and floors influences how much heat gets inside. Well-insulated homes hold cool air more successfully, which lowers the cooling load.
Air infiltration rate: This describes how much outside air enters through leaks or cracks in the building envelope. Homes with a significant air infiltration requires more cooling to neutralize the warm, humid outdoor air that makes its way inside.
Home orientation and window layout: The direction your home faces influences its sun exposure, which in turn impacts your home’s cooling load. A single-family dwelling with expansive south-facing windows absorbs more heat and necessitates a more sizeable 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 conditioners are created equal. It’s essential to buy a trusted brand for reliability and longevity.
Efficiency rating: The seasonal energy efficiency ratio (SEER) shows the amount of heat an air conditioner can eliminate per unit of electricity it consumes. Higher SEER ratings signify higher efficiency, minimizing your utility bills.
Maintenance requirements: Regular maintenance keeps your system operating effectively. Most air conditioner producers recommend yearly tune-ups to find and fix small problems before they turn into pricey repairs.

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

Selecting the best air conditioner size can be stressful. The Experts at Service Experts Heating, Air Conditioning & Plumbing are here to assist with all your cooling and heating needs. We can provide you with custom cooling strategies to enhance home comfort, efficiency and energy savings.

From establishing your unique cooling requirements to helping you browse different brands and efficiency ratings, we’re there for you at every step. For help choosing 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.