These 7 HVAC abbreviations will help you save thousands on your energy bill.

The 7 HVAC Terms That’ll Save You Thousands

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Have you ever bought a new appliance or HVAC system but aren’t too sure what on earth do terms like SEER and AFUE mean?

You’re not alone.

I used to feel the same way when I’d see the yellow papers on the new appliances…until I learned what they meant and how they work.

And the best part is that you can learn them, too. There’s only 7 to really know, and they’re not hard to follow.

These terms, although confusing at first, are some of the most helpful pieces of information that can help YOU save money in the long run. Not only will they help you deal with contractors like THA, but also this information will be helpful when you purchase anything heat-related – from stove-tops to heaters. As a more informed consumer, you’ll be able to make better purchases all around.

Top HVAC Terms To Know

HVAC Term #1: HVAC – Heating, Ventilation, and Air Conditioning

Own an air conditioner or a furnace at home?

Then, what you have is called an HVAC unit or HVAC system.

According to Scott Heating’s website, he explains the primary functions of the typical HVAC unit best:

“The main parts of the HVAC system are a heating, a ventilation, and an air-conditioning unit. Furthermore, modern systems include an air filtration and cleaning element as well. Heating is most often done by a furnace or a boiler.”

Other common HVAC systems includes boilers, humidifiers, radiant floors, and swamp coolers, just to name a few. These aren’t cheap, and can be very expensive if you have a commercial HVAC system.

HVAC Term #2: BTU – British Thermal Units

Aside from watts (W) and kilowatts (kW), you may occasionally bump into BTU, especially if you’ve imported your HVAC system from outside the USA.

As a reference, one BTU equals the amount of heat required to raise or lower the temperature of one pound of water one degree Fahrenheit. It’s just a standard unit of measure that refers to heat – you may have also heard of this acronym from stove tops or cooktops – they are one and the same.

HVAC Term #3: AFUE – Average Fuel Utilization Efficiency

Defined by Trane as “a gas furnace’s efficiency in converting fuel to energy”, the higher your AFUE rating is, the more you’ll save.

For example, if your appliance’s AFUE rating is 80, this means that 80% is used to efficiently heat up your home while 20% will escape as exhaust. Obviously, the higher the better since it’s less efficient and there will be less waste.

HVAC Term #4: SEER – Seasonal Energy Efficiency Ratio

You’ve probably seen this term a ton of times on those yellow Energy Star papers, but for it’s for a good reason: it measures your units’ cooling efficiency.

The SEER rating is determined by the Air Conditioning, Heating, and Refrigeration Institute by dividing the cooling output by the total electric energy input.

Just like AFUE, the higher the rating, the better it is for you and your home, especially if you live in very cold places where you’ll have the heater on for a long time. Here in San Diego, it’s not nearly as important as it is for those in really cold areas like Wyoming.

HVAC Term #5: HSPF – Heating Seasonal Performance Factor

This abbreviation refers to the measurement of heat during an entire heating system.

Just like SEER and AFUE, the higher the rating, the better efficiency your HVAC unit has.

Susan Carmichael says that she was surprised to learn about this term after years of having her own heating system. It’s helped her keep in mind what to really look out for when she purchased a new one in 2018.

HVAC Term #6: EER – Energy Efficiency Ratio

You may have noticed that EER is similar to SEER.

That’s because the EER is the older way to measure cooling efficiency.

The only difference between the two is that the EER is measured by a set outside air temperature, a set inside air temperature and a 50% relative humidity.

HVAC Term #7: MERV – Minimum Efficiency Reporting Value

Back in the day, the MERV was included on Energy Star approved appliances, but as time went by, it was soon replaced by SEER.

But if you do see a MERV rating, look for a high rate.

High rating = better efficiency.

Overall though, this term is less relevant so you might not see it as much.


Although it’s common sense to do your research before making purchases, unknown abbreviations can make anyone’s head hurt. Just make sure that you take the time to understand what each of them means before you shop around for a new system or before you get an unnecessary HVAC repair done.

But here’s the thing: these terms are here to help make life easier for you.

By being an informed shopper, not only will you make better decisions, you’ll also save money in the long-run.

If you’re in the San Diego area and need assistance with your new HVAC system, give us a call at (800) 300-5441. 


Are you new to the world of HVAC or unsure what the lingo means? These 7 HVAC terms will help you and your wallet save more money.

Do you live in San Diego and are in need of an HVAC or plumbing service? Call (858) 571-8865 to schedule your next repair, install, or anything else in between today!

Have a question? Use the form below or call at (858) 284-4753. We'll get back to you as soon as possible.

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