child with glasses reading book | HVAC Terms 101: AFUE, SEER, NATE | KS Serviceschild with glasses reading book | HVAC Terms 101: AFUE, SEER, NATE | KS Services

The heating and cooling industry is full of acronyms and HVAC terms often confusing for homeowners. These HVAC terms give you important information about each system, and knowing them is extremely useful when making decisions to repair or replace your equipment. KS Services decodes heating and cooling terminology, giving you a rundown on the HVAC terms you need to know.


AFUE is one of the HVAC terms relating to heating. It is an acronym for Annual Fuel Utilization Efficiency. AFUE shows you how efficiently a furnace or boiler uses fuel. Expressed as a percentage, it compares the unit’s annual heat output against the amount of fossil fuel energy consumed during the same time period.

For example, a furnace or boiler with a 95 percent AFUE uses 95 percent of the energy it consumes to create heat for your home. Consider the remaining five percent lost, via the chimney or other methods. AFUE does not account for energy loss through duct systems.

The higher a furnace or boiler’s AFUE rating, the higher fuel efficiency it offers. In many cases, AFUE ratings affect the price of a unit – the higher the AFUE, the higher the price tag.

Don’t let this stop you from purchasing a higher AFUE heating system – the savings these units generate through conserving energy can pay you back for the additional cost over a period of years while you use the system.

All new furnaces display the unit’s AFUE. This makes it easy for you to compare efficiencies of the different models available for purchase.

New furnaces and boilers have AFUE ratings ranging from 80 percent to up to 98.5 percent. Your old, inefficient heating equipment could have an AFUE of 56 percent to 70 percent, as previous standards for equipment manufacturers were not as high as they are now.


SEER is one of the important HVAC terms you should know concerning your air conditioner or heat pump. SEER is an acronym that stands for Seasonal Energy Efficiency Ratio. An air conditioner or heat pump’s cooling efficiency is measured by SEER.

To calculate a unit’s SEER rating, divide the unit’s total cooling output over an average cooling season by the total amount of electric energy consumed by the unit.

As with the HVAC terms for heating efficiency, the higher a unit’s SEER rating, the more efficient it is. Homes in the south require new air conditioners and heat pumps to be at least 14 SEER

Higher SEER units typically do come with a higher price tag, but generate substantial savings which make your investment worthwhile.


NATE stands for North American Technician Excellence, and it’s one of the HVAC terms we love – because we are NATE-certified! NATE is a non-profit certifying organization for HVAC technicians.

With rigorous testing and ongoing education, NATE verifies the professional competency of heating and cooling technicians. They also help each technician stay up-to-date on the industry’s advancements through required continuing education and recertification.

NATE-certified technicians are not only highly knowledgeable and skilled in their craft – they also offer elite customer service. NATE-certified technicians make sure the job is done right the first time. A NATE technicians’ work receives fewer callbacks compared to non-certified technicians.

KS Services – Happy to Help with HVAC Terms as Well as The Big Stuff – HVAC Repair, Service and Installation

Knowing these HVAC terms helps you find the right energy performance for your new heating and cooling systems, installed by the best in the business. Let our NATE-certified technicians assist you with your AFUE and SEER understanding.

We can set you up with new heating and cooling equipment to provide energy-saving benefits. We also provide finance options for your convenience. Contact us today to learn more.