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What size AC unit is best for me?

A few years ago, if you by chance looked in the windows of my house, you would probably have seen me, balancing on a chair, with my hands held up to one of the ceiling vents, double checking to make sure that cool air was coming out.  It always seemed to me that while the AC was running and cool air was flowing, my house was still too hot!  I had the AC  system checked and serviced in the spring but something still just wasn’t right.  I called the AC  contractor and had him come out – again.  After tons of questions and him looking around he delivered the news:  the builders model AC unit was just too small for my house and not powerful enough to cool a home of my size.  I couldn’t imagine how an AC unit could be too small but apparently it was.  So, how you do determine if your AC unit  is too big, too small or just right for your house?  Don’t use the Goldilocks method.  Here’s how to tell:

There are many things that a contractor will do when determining the best AC unit size for your home.  The first thing is called a load calculation.  This checks the insulation in your house, as well as checks the sizes of windows.  Are they double paned?  Single paned?  The contractor should also check the square footage of your home and if you have skylights. Skylights add extra heat to your home and need to be accounted for.  The shading of your home comes into play too.  Are there a lot of trees around your home?  Are you in an open area with no way to block the sun?  Do you get morning or afternoon sun?  These are just some of the questions a reputable contractor should ask you before you install any AC system in your home.

It really does pay to determine the sizing of your new AC unit. Don’t be fooled into thinking that square footage alone can, or will, determine the best sized AC unit you need.  So, be cool! Make sure you choose a reputable contractor and confirm that all the right questions are asked before you install any AC unit or system in your home.