What Is a SEER Rating?

SEER stands for Seasonal Energy Efficiency Rating. It is a rating system used to determine the energy efficiency of all air conditioning units sold in the country. The higher the SEER, the more energy efficient the unit. Understanding how SEER works can save you money when it is time to consider the purchase of a new air conditioning unit.

As opposed to older energy efficiency rating systems, SEER rates the efficiency of an air conditioning unit over the entire season. The SEER rating system will test an air conditioner’s energy efficiency in temperatures from 65 to 104 degrees. The old energy efficiency standard only tested the energy efficiency of a unit when the temperature was 95 degrees. Thus, SEER is a more accurate means of truly testing energy efficiency in all cooling situations.

There is one caveat to keep in mind, though. If you have poor insulation or leaky windows or ductwork, you will not see the same level of energy efficiency that the SEER rating predicts. It is always best to provide the proper insulation for your heating and cooling systems, so they can give their best performance. At Charleston Heating and Air in Charleston, your local HVAC provider, we can provide you with personalized information about your air conditioning unit as well as on how you can optimize its insulation.

The Minimum SEER Rating Changes Over Time

The US Department of Energy regulates the SEER ratings of air conditioners sold in the country. There is a minimum SEER rating that every air conditioning unit in the country must meet. Around once per decade, the government increases the minimum SEER ratings.

Today, there are two minimum SEER ratings in the country. Southern states, like South Carolina, must have a SEER rating of 14 or more. In colder climates, such as in the Northern states, the SEER only must be 13 for new units sold. In 2023, the SEER for Southern states will go up to 15. That is why most air conditioners sold today have a SEER of 15 or more.

How SEER Ratings Influence Repair Versus Replace Situations

If your air conditioning unit has been in service for 15 years or more, it likely has a SEER rating closer to only 8 or 9. If you install a new air conditioning unit with a SEER rating of 15, you could save as much as 47% on your electricity cost for the new unit each year. In the local Charleston area, where everyone relies upon their air conditioners to get them through the warmer months, the energy savings over time could offset the cost of the new system.

There are a few things to look for in considering if your air conditioning unit may be nearing its end of service.

  • Using more energy
  • Lower cooling output
  • Frequent need of repairs
  • Strange sounds

In some cases, the unit is just in need of repair and will faithfully serve you for many more seasons. If your air conditioning system is 15 years or more old, it may be near its end of life. Central air conditioning units tend to last around 15 to 20 years, while heat pumps tend to last 20 to 30 years. It makes sense to weigh the costs and benefits of replacing an older unit that is more expensive to run with a new unit that saves on electricity.

How SEER Ratings Influence Choices Between New Air Conditioning Units

Most people will opt for an air conditioning system with a SEER rating in the range of 15 to 18. There are units on the market as high as 33 SEER, but this is not as common. The higher range SEER units most commonly available for homeowners have a SEER rating from 19 up to the mid-20s.

Today, the units with the highest SEER ratings cost quite a bit more than the air conditioning units with SEERs closer to the government-set minimum. The reason for this relates to the technology in the units with higher SEERs. If a unit has a 17 SEER rating or above, it will be equipped with either a two-stage or variable compressor. It will also have a condenser fan motor that is variable speed.

When the higher SEER units are working, they spend 80% of their time, on average, operating in low mode. These higher SEER Units power on in high mode to get the room cooled and then maintain that temperature in low mode. The units that are at a SEER of 14 to 16 will operate at either high mode or off because they have no other mode. So, if 14-SEER devices are blowing cold air, they are always in high mode, using more electricity than higher SEER units.

A 20-SEER unit will be 43% more efficient than a 14-SEER unit, but it will cost on average $3,000 to $5,000 more for your initial purchase. This is the reason that most homeowners opt for new air conditioning units in the range of 14 to 18 SEER. The energy savings for the higher SEER units do not justify their significantly higher cost in most cases. 14-SEER units still save the average homeowner quite a bit on electricity as opposed to their end-of-life, older air conditioning units, though.

There are a few scenarios where the higher SEER units may make some sense. If you are in an HOA that limits noise levels, higher SEER units are quieter. Also, if the unit must be by a bedroom window, it may be better to go for the higher SEER unit.

Using a SEER Calculator

Online you will find SEER calculators. They allow you to enter your city and state data along with the size of your air conditioning unit in tons. You will also need to find your current unit’s SEER or look it up online as well as the SEER for the unit you are considering installing. The SEER of air conditioning units is found on their sticker. The calculator will estimate how many hours of air conditioning you need per year in your city. They are also programmed with estimates of how much you pay per kilowatt hour for electricity. Based upon this data, the calculator will estimate your yearly electricity cost using your old unit and allow you to compare the cost to the projected yearly electricity cost of your new unit.

You can also use the SEER calculator to compare two new units with different SEERs. That will help you decide which unit has the best ratio of cost to energy savings.

Charleston Heating and Air in Charleston for HVAC Services and More

At Charleston Heating and Air, we have been proudly providing HVAC service in our Charleston community since 2009. We are here to help you make decisions between repairing and replacing air conditioning units. We are the largest HVAC service provider in the area. Besides heating and air conditioning installations, maintenance, and repair, we also provide plumbing and electrical services in our local area. For six years, we have won local “Best of” awards in Charleston. We are the service provider that you can trust to install an air conditioning unit as well as install a new tankless water heater. We offer to finance on approved credit.

Contact us today at Charleston Heating and Air in Charleston with any questions you have on SEER ratings and new air conditioning installations.

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