How Do I Choose The Right Size Air Conditioner?

Written By 5 Star Charleston Heating & Air
April 25, 2022

There’s only one question you should ask when purchasing a new cooling system: “What size air conditioner do I require?” It’s critical to get the appropriate fit, or your comfort and expenses will be harmed over the life of your new air conditioner. 5-Star Charleston explains what you need to know about air conditioner sizing and how to choose the correct unit size for your home in Charleston, Kiawah Island, and surrounding areas.

What Does Air Conditioner Size Mean?

The capacity to cool a space is measured by the amount of BTU’s (British thermal units) in an air conditioner. The physical dimensions of the new unit are not taken into account when sizing an air conditioner; rather, it is dependent on how much heat it can remove from your home. Tonnage refers to the ability of an air conditioner to remove heat from a building, not its weight.

The tonnage of an air conditioning system is the amount of heat it can remove from a building in one hour to keep it cool. The measurement of heat in the HVAC industry is measured in British thermal units (BTUs), and each ton of air conditioning has 12,000 BTUs of heat. As a result, a 2-ton air conditioner can remove 24,000 BTUs of heat each hour; a 3-ton unit removes 36,000 BTUs per hour, and so on.

Why It’s Important to Buy the Right Size Air Conditioner

When you discover the correct air conditioner size for your home, it’s critical that you stick to that size when purchasing a new cooling unit. Air conditioners aren’t one-size-fits-all, and it’s not advised to scale up or down in order to get a better fit like you can with clothing and other items. This is because the size of your air conditioner will influence how much energy it takes, how it operates, and the amount of comfort inside your house.

When you buy a window air conditioner that is too small, it won’t be able to cool the space enough to keep rooms at an ideal temperature. The unit will run more frequently as a result of its shortcomings, wasting energy and increasing wear and tear, which leads to earlier system failure.

An enormous air conditioner won’t keep your house pleasant, either. The AC unit will rapidly cool but not fully, resulting in discomfort. This causes short cooling cycles that strain the equipment, add wear and tear, and cause the system to go offline sooner than a properly sized air conditioner. They will also not run long enough to remove moisture from the air.

What Size Air Conditioner Do I Need?

Working with a certified HVAC professional is the easiest method to figure out what size air conditioner your house requires. Many elements influence the appropriate size AC unit for a home, even if it’s just square footage.

The cooling load (how much heat has to be removed) of various components, including:

  • Square footage
  • Number of stories
  • Ceiling heights
  • Number of windows and doors
  • Insulation levels
  • Building materials
  • Number of occupants
  • Home’s orientation

The following factors are incorporated as a skilled HVAC technician performs a Manual J load calculation, which provides the cooling load for your home. This equation determines how many BTUs of heat must be removed from the room every hour, so you’ll know how much capacity in tons you need for your new air conditioner.

Find the Right Air Conditioner for Your Charleston Home

If you’re looking to purchase a new central air conditioner, 5-Star Charleston is the place to call. Our expert HVAC technicians will choose the best size unit for efficient performance and pleasant comfort in your home, as well as provide expert installation so that your new cooling system works as expected. To request an estimate for air conditioner installation, contact us today.

Related Article: Portable vs. Window Air Conditioning


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