What Is a BTU and Why Is It Important?

July 7, 2020

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The very abbreviation of the title may take you back to a high school chemistry class, one in which you forgot everything but the eyes of your crush who sat in front of you. If you live in Phoenix though, BTUs are an important part of how you stay comfortable in your home.

BTU stands for British Thermal Unit, and you’ve likely seen the term at some point if you’ve inspected a heater of any kind in North America. The more BTUs you use, the more money you’re going to pay the next time your bills roll around.

Precision Air & Plumbing knows just how important these units can be, so we want you to know more about how they work. Learn more about how they relate to your appliances and how you can better control them.

Measuring the Energy

Heating up a pound of water from 75° to 76° degrees takes a certain amount of energy, and that energy is defined as a BTU. (Technically, this only refers to water found at sea level, though you’ll find BTUs in higher elevations too.) If your home is huge and drafty, you’ll need more BTUs to keep it at an optimal temperature.

If you’re talking about BTUs in terms of heating and cooling systems, it refers to the number of BTUs that can be added or taken from the air. During summer, you’ll need plenty of thermal units removed so you can cool off.

When you inspect appliances and compare their prices, you might be surprised to see that even small, portable heaters and coolers have relatively high BTUs. This is because they can still produce a lot of power without needing a larger casing. (And one of the reasons why your space heater can rack up your electrical bill pretty quickly)

Experts recommend using these numbers as a way to better understand different equipment that is roughly the same price. A unit with higher BTUs may be a better buy because it provides a higher capacity for the same price.

Caring for Your Cooling Systems

Arizona can get pretty toasty during the year, which can cause many homeowners to overuse BTUs without realizing the pressure they’re putting on the systems. Even though you want a powerful appliance that can cool off the air immediately, too many BTUs will cause the air conditioner to cycle at a high pace, switching off and on rapidly to keep a balance in the air. If you overdo it, this will cause your unit to wear out much faster than it ever needed to.

But opt for too few BTUs, and you’ll end up with a cooling system that can’t keep up with the peaks of the day. Because the system was never designed for such extreme temperature spikes, it will run all day at full power and still never reach your desired temperature. This leaves you with an uncomfortable home and an air conditioner that’s constantly on the fritz. Talk about a lose-lose situation!

Squaring Up the Space

There are a number of ways to determine how many BTUs you need, including the overall energy efficiency of your home. However, the standard way to map it out is based on the square footage of the home or area you’re hoping to cool. A tiny studio apartment may only need 10,000 BTUs, but a 1,500 square foot home will need closer to 30,000.

Keep in mind that BTU recommendations are by no means set in stone. Again, this is because everyone’s structure is different. Some people have ventilation that can’t be fixed without redoing the entire system, meaning the home is treating the outside air nearly as much as it’s treating the inside. If you live in a newly built or recently renovated home though, your energy efficiency may allow you to run your air conditioner for significantly fewer BTUs.

What Will Interfere with Your BTU Usage?

Here are a few things that keep in mind if you’re trying to decide the right BTUs for your home:

  • Heat rises, so your air conditioner will likely have to work harder to cool the top floors than the bottom.
  • West-facing rooms in direct sunlight will quickly absorb the rays and make for warmer temperatures as well.
  • The more people gathering in the rooms, the warmer it will be and the more BTUs you’ll need. (Around 600 per extra person.)
  • Appliances that add heat, like the oven, will also need additional BTUs to maintain the desired temperature.

So whether you’re having a party or you just want to get the most utility out of each space, it’s important to account for these extra factors. And as you might expect, you can start to subtract BTUs for basements, uncrowded spaces, and rooms without a lot of windows.

Anticipating Your Needs

It’s not necessarily easy to control for all scenarios. After all, the rooms in your home are interconnected, and the air will eventually begin to circulate. However, you can find solutions that are more tailored to your home’s layout if you know where to look.

Precision Air & Plumbing is notorious for our skills in an area that’s filled with a sometimes unforgiving sun. We target the most uncomfortable parts of your home, so you can actually use the entire space rather than just the cooler rooms or those that have a window unit.

Our staff will show you where you may be losing efficiency and tell you how you can correct the problem without breaking the bank. For some homeowners, the fix may be a simple one. Others may need to invest in their cooling systems to ensure that they’re paying less in utility bills over time.

Taking Care of Your Home

Whether you’re turning on a faucet or switching off a ceiling fan, your home’s functionality is based on a number of mechanics that you likely don’t even think about (until something goes wrong of course). But having a better handle on the details behind your appliances and amenities can go a long way toward lowering your utility bills and preventing possible damage down the line.

If you want to learn more about how you can make smarter changes to your home, Precision Air & Plumbing is here to help. When you call us, we quickly get to work addressing the problems that have likely been building over time. Sometimes it just takes a little awareness to begin modernizing your home and cutting back on the amount of energy you use.