What Size AC Unit Should I Get for My Home or Office?

What Size AC Unit Should I Get for My Home or Office?

Having the right sized air conditioner is a key component in cooling your space effectively.  A unit that is too small has to run constantly, playing catch up all day trying to fill a space that it isn’t designed for. A unit that is too big will turn on, cool the space quickly and then shut off, which sounds good but the heat will come back in and the unit will click back on and then back off.

This on, off, on, off uses a lot of energy and more energy equals more money. At Day Heating & Cooling, we are in the business of keeping you cool and saving you money.

Air conditioners are measured by tons, but this isn’t the weight of your appliance in tons. The tonnage of an AC unit is based on how much the unit can cool.  A 1 ton air conditioner = 12,000 BTUs.  

Climate Zone Map

A BTU, or British Thermal Unit, is the unit of energy that equals 1055 jules. One BTU is the amount of energy needed to cool 1 pound of water by 1 degree Fahrenheit. A one ton AC unit can cool 12,000 pounds of water by 1 degree, each hour.

Home units can be anything from a 1-5 ton unit, and they increase by .5 as they go up. Size matters, but bigger is not necessarily better — having an accurately sized unit is the way to go.  

The old school equation to finding out the right size unit for you is as follows:

  • Take the square footage of your space
  • Multiply by 25
  • Divide by 12,000
  • Subtract .5.  

Climate zones also make a difference in determining the correct unit for you, so you can follow the equation or contact us for help!

We are happy to assist you in finding the right appliance for your home or office. Call us at 503-363-4822, or request service online today!

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Call us at 503-363-4822!