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SEER 2 vs SEER: Understanding The New Efficiency Ratings

The U.S. Department of Energy (DOE) is mandated by law to "periodically amend energy conservation standards for certain equipment, but only if the amendments are energy-saving, technologically feasible, and economically justifiable."

In that regard, since 1992, manufacturers of residential central AC systems and heat pumps have been strictly complying with DOE's energy conservation standards.

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The Latest Efficiency Ratings

Recently, the DOE further revised the mode of HVAC testing and in turn the conservation standards. It is from these new testing procedures that SEER2 was birthed.

For that reason, from 2023 onward, all new residential central air conditioning and heat pump systems sold in the United States will be required to meet new minimum energy efficiency standards.

Of course, since 2015, new energy efficiency standards were set for central ACs sold in the northern parts of the USA and those sold in the southern parts. However, the new standards taking effect on January 1, 2023 set the updated SEER rating to new, more accurate measures.

The new SEER 2 regulations will affect heat pumps, AC condensing units, single packaged units, gas furnaces, and evaporator coils in the different HVAC regulatory regions.

So, whether you're in the market for a brand-new ductless AC or comparing the latest central AC systems, you might want to take some time to understand how the changes will affect your region and by extension, your home or HVAC business.

With that in mind, let's now delve a bit more into what exactly SEER is and how SEER 2 and SEER stack up.

Heighten Your Home Comfort With Upgraded Efficiency!

What Is SEER?

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Short for Seasonal Energy Efficiency Ratio, SEER rating simply indicates the cooling output of your AC unit divided by its total power consumption during the entire cooling season. In other words, the SEER rating tells you how much heat has been removed from your conditioned space during the cooling season.

SEER is an important metric for you as a homeowner as it helps you compare different systems to determine the more efficient one, especially when shopping for a newer model. From the rating, you can easily compute the amount of energy and money your AC will use up yearlong.

The DOE requires all new AC units to satisfy the minimum efficiency as indicated by the SEER rating. However, don't be surprised when you acquire a ductless AC or bump into central AC systems that surpass the minimums. Successful manufacturers are going above and beyond to prioritize energy efficiency, thanks to technology infusion.

As a rule of thumb, the higher the SEER rating, the higher the energy efficiency and indoor comfort you get in return.


The emergence of SEER 2 marks a remarkable milestone in the world of heating and cooling. So, whether you are an HVAC contractor or homeowner, sharing in the gains of this milestone requires a good grasp of SEER 2.

So, what is SEER 2 and how does it compare to SEER?

The SEER rating has been used to measure the efficiency of HVAC equipment such as central ACs since 1992. The rating is calculated by dividing a unit's British Thermal Unit (BTU) by watt-hour.

The introduction of SEER 2 regulations doesn't scrap the existence of SEER. In fact, SEER will continue as an efficiency measure and still apply the same formula. The only change that comes with SEER 2 is the testing conditions for SEER.

Higher External Static Pressure

At the outset of 2023, testing for HVAC units will take place under higher total external static pressure than before. The individual pressure variations will fluctuate based on the region of the testing. Varying the conditions of static pressure is primarily geared at accuracy. The testing environment will reflect with better accuracy the type of static pressure registered inside a home.

Currently, the existing SEER conditions overlook the effect of ductwork on a unit's external static pressure. In effect, this results in ratings that are not as accurate as they ought to be.

Thus, with the implementation of SEER 2, most units undergoing testing may end up with lower ratings that are more accurate. This applies to split system ACs, split system heat pumps, and single packaged units.

For instance, under the new SEER 2 requirements, residential central AC systems with a BTU less than 45,000 should have a SEER 2 rating of 14.3 (an equivalent of 15.0 SEER). Systems with a BTU higher than 45,000 should have a SEER2 rating of 13.8 (an equivalent of 14.5 SEER).

Prepare for SEER 2 With New Central AC Systems

Prepare With Confidence!

From 2023, all AC units acquired in the Southeast region must meet the new SEER 2 requirements to be installed. As a forward-looking HVAC contractor or homeowner, this is not information to take lightly.

Thus, a good grip on SEER 2 vs SEER will help you to confidently prepare for the coming changes and keep you compliant when they take effect.

We sincerely hope this post has been a helpful eye-opener to avoid any future installation surprises.

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