How do I know what size air conditioning system to buy?

The only way to know the proper size air conditioning system for your home is to conduct a heat loss/heat gain load calculation. This calculation will determine your home’s heating and cooling needs by taking into account your home’s square footage and how much heat is gained or lost through windows, doors and walls. Once the load calculation is complete, a system can be designed to fit your home’s needs.

Interestingly, according to the Department of Energy and various equipment manufacturers, an improperly sized system can reduce the life expectancy of your system and cost you more money to operate. For instance, if a system is too large, it will start and stop more frequently than an adequately sized system, because it heats or cools the home quicker. This may sound good, but it causes a lot more wear and tear on the system and reduces its life expectancy. On the other hand, if a system is too small it will run continuously, using more electricity and costing you more money without ever really doing the job as intended.

There are many variables to consider when properly designing a heating and air conditioning system, such as square footage, insulation values, number of doors and windows and sun exposure. Call your local Aire Serv if you’re wondering whether or not your system is the correct size.

- Sam Harris, Aire Serv of the Gold Country