What Size Air Conditioner Do I Need?

It all comes down to cooling load

If you decide to invest in a central air conditioning system you need to consider the following factors: the climate, the size and type of your home, your budget, the age of your house, and the needs of your family.

That’s a lot to consider but perhaps the most important factor is size – or, more accurately, size matching. The question is, what are you matching the size of your cooling system to?

Some air conditioning contractors will reduce the A/C size matching equation to a BTU–to-square footage formula but that approach won’t help you get the most from your cooling equipment. To do the job right – whether you plan to use a central air conditioner or heat pump – you need to consider your home’s cooling load.

What is cooling load?

Cooling load is a calculation that determines the amount of heat that needs to be removed from your home to consistently maintain the temperature set on your thermostat.

A number of factors contribute to cooling load, including:

  • The square footage and layout of the house
  • The quality and quantity of your insulation and air sealing
  • The type of construction materials from which your house is built
  • How much sun or shade the house is regularly exposed to
  • The number, type, and location of windows you have
  • And more