Finding Goldilocks: Getting The Right Size Air Conditioner

When you are getting a new air conditioner, it is important to get one that is the right size. Too small, and it will struggle to keep your home cool. Too large, and it will cool your home, but you are wasting energy and it will actually struggle to complete a full cooling cycle. Understanding what goes into this calculation will help you tell if your HVAC tech complete your air conditioning installation.

Where Do You Live?

The first and easiest question that goes into your air conditioning size is location. In particular, you need to look at the average temperature in your area during the summer. The bigger the temperature differential between the air inside your home and the air outside it, the harder your air conditioner will have to work to keep up.

Fortunately, this is something that most HVAC techs will know by heart within a few weeks of getting on the job. You can use a zone chart, but keep in mind that if you live in an unusual location, such as at a high elevation, you might have to fudge the ranges a bit to get it right.

How Big Is Your House?

The second half of the basic calculation is the square footage of your house that the air conditioner needs to cover. More space equals more power. The exact ratio will vary depending on the efficiency of the air conditioner and the experience of the installer.

Since newer units are far more efficient, expect your new air conditioner to be quite a bit smaller than your old one, especially if you opt to spend extra on a a high efficiency unit. The good news is that your new air conditioner should mean a decrease in your electric bill.

How Efficient Is Your House?

Now it's time to get into the details of your house. In particular, it is important to consider your home's energy efficiency. Check to see if the insulation in your walls is sufficient for your region, and whether their are leaks around your doors and windows. If your home is sealed properly, you can use a smaller air conditioner, as it will be easier to maintain the correct air conditioner.

In addition, the technician might consider whether your home is shaded, and if you have invested in additional heat mitigation measures like heavy curtains or solar films on your windows.

How Many People Live in Your House?

The final element in this equation is the number of people living in the house, as well as their lifestyle. People create heat, as do their cooking, laundry and electronics. If you pack several people into a small home, the temperature will rise far quicker than if only one or two people were living there.

You might also want to let the technician know if you have any lifestyle choices that could put a strain on your air conditioner. If you love to bake or have large computers, you will be putting an unusual amount of heat into the space. Alternatively, if you are committed to only running major appliances at night, and are willing to increase the ambient temperature in the house during the summer, you can reduce the size of air conditioner you need instead of increasing it.

There are a few elements that go into picking out the right air conditioner for your space. By working through all these items, you can be sure that the air conditioner you purchase will be able to run at maximum efficiency and will last as long as possible. Go too big or too small, and you are asking for an uncomfortable house and many future repairs.