Choosing the Right Air Conditioner Size For Your House

Unlike simpler home appliances, you can’t just pick out an air conditioner for your Arizona home off the shelf. You’ll find your goal of keeping your home cool during our sweltering summers hampered as much by a too-small unit as by an overly large one. Quite a bit of science can go into the calculation that will tell you which size of air conditioner you need. At Precision Air and Plumbing, our certified techs will do the calculations that will provide you with the best cooling solution. In the meantime, learn why it’s so important to choose the right air conditioner size and some of the factors that our certified technician will take into consideration.

Why You Should Calculate the Right AC Capacity for Your Arizona Home

Most people understand why they need to buy an air conditioner that’s large and powerful enough to effectively cool their homes. On the other hand, some local homeowners believe that bigger is better, and that’s not always true. Here in Arizona, we experience plenty of triple-digit heat during the summer. We also have periods of varying humidity. When you have the right-capacity air conditioner installed, you can relax in cool comfort.

According to Energy Star, air conditioners work by removing both excess humidity and heat. Over-capacity units will cool the air very quickly, but in that shorter time, they won’t effectively remove enough humidity. Even though the unit can cool your home, the air might also feel clammy. In this case, a smaller unit would work better to cool and dehumidify your house.

You can visit our air conditioning services page to learn about some of the things our technicians will use to calculate the size of your unit. These will include not just the size of your home but also your location’s unique climate, seasonal humidity variations, number and kind of windows, home insulation, and much more. They’ll even factor in ceiling heights, shade trees, and the sort of heat they expect your other appliances to generate.

Can You Calculate the Proper Size for Your Home AC Without a Tech?

Our certified techs will consider dozens of factors before suggesting the size of the air conditioner that your home needs. Still, you can make some rough estimates on your own. These start by using calculations based upon BTUs or tons per square foot.

Using Tons per Square Foot to Calculate AC Size

For example, some contractors will simply estimate using tons per square foot as a rough guide. For example, they might suggest one ton of capacity for every 600 square feet. However, this rule-of-thumb calculation doesn’t take into account important factors like windows, existing insulation, specific climate, or even the number of people who generally occupy the house.

In Arizona summers, a simple estimate like this could suggest a smaller unit than you need for the warmest days. In an energy-efficient home, this method could also suggest one that’s too big. Either way, you won’t get an air conditioner that will keep you satisfied. The larger unit will cost more and won’t dehumidify well; the smaller unit will have to work too hard and won’t keep up with the heat on the hottest days.

Using BTUs and Square Feet to Calculate AC Size

You will mostly see air conditioners sized by BTUs. BTU refers to British Thermal Units, an old and traditional measure of heat. It’s technically defined as the amount of water you would need to increase the temperature of a pound of water by one degree Fahrenheit. Today, it’s often also used as a measurement of energy output. Scientists might use joules instead to measure energy; however, lots of industries still stick with BTU.

The BTU rating of an air conditioner will refer to its energy output per hour. You can visit to see rough calculations for BTU based only upon square feet. For example:

  • Energy Star estimates that 1,200 square feet would require 21,000 BTUs per hour.
  • As another example, they calculate that 2,500 square feet would need to have a 34,000-BTU unit.

Still, these rough calculations only use the size of the area and not any of the other important factors. The figures represent general averages across the country, so they’re not likely to precisely calculate requirements for Arizona summers. Also, a true technical evaluation may suggest a smaller unit for a new, energy-efficient, and insulated home. As a matter of fact, if your home lacks good insulation or suffers from drafts, it’s a good time to remediate those problems when you buy your new air conditioner.

Better insulation and draft protection will help you conserve energy during the summer and winter. In fact, the money that you could save on buying a smaller unit and enjoying lower power bills should rapidly compensate you for that sound investment. At the same time our tech visits to calculate your AC needs, he can combine those figures to also recommend insulation services.

Get an AC-Size Estimate With Our Online BTU Calculator

We also have a handy AC BTU calculator that you can use at any time for a quick estimate. To get started, you just have to slide the bars to tell the tool your total square feet, if you have a basement, the number of people in your home, and the nature of your relative climate. We still suggest having a free, professional evaluation from one of our techs; however, this online BTU calculator might help you start comparing units.

Find the Right-Sized Air Conditioners for Your Arizona Home Today

Here at Precision Air & Plumbing, we want to develop a lifelong relationship with our customers. That means we work hard to make certain that you’re satisfied with such an important choice as the air conditioning for an Arizona home. Our technicians will factor in the local environment, your home’s energy efficiency, and many other details before offering you suggestions for your AC system.

More than that, they can provide you with suggestions to improve energy efficiency. In turn, you can make the right moves to ensure you can keep your house comfortable while conserving as much energy as possible.

Call upon us here at Precision Air & Plumbing today to find the best air conditioner for your own Arizona home. If you just try to buy a new AC with the same rating as your old one, you might make a mistake that will cost you money and comfort. For one thing, AC ratings have changed over the past few years. Also, your home environment may also not have remained exactly the same or may not even have been properly accounted for in the first place. Our certified technicians can also offer solutions to help improve your home’s energy efficiency, which could mean reducing the size of the unit you need.

Call or email us right away to get started, and we also offer emergency services 24/7.

mbndev May 19, 2020

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