Texas Comfort Air

What’s a SEER Rating, and Why Does It Matter?

What’s a SEER Rating, and Why Does It Matter?

Your HVAC system’s SEER, or seasonal energy efficiency ratio, indicates how efficiently it uses energy to cool your house. Units with higher SEER ratings offer better efficiency. That can result in substantial and immediate utility savings, especially in a hot climate like Elgin, Texas. However, top-of-the-line HVAC equipment with SEER ratings above 20 typically cost double or even triple the price of baseline models. Read on to learn more about why a SEER rating matters.

Cooling Load and Efficiency

Calculating your home’s cooling load is a complex process that involves dozens of variables, including climate, house orientation, and window coverage. The air conditioner’s SEER rating won’t change that. If your home requires 48,000 BTU/h of cooling to stay comfortable year-round, it’ll require a 4-ton air conditioner regardless of its SEER rating.

A Simple Calculation

However, that rating does play a significant role in determining electricity usage, which you can calculate by dividing the cooling capacity in BTU/h by the SEER rating. Let’s look at three different 4-ton air conditioners, dividing 48,000 BTU/h by their respective SEER ratings of 10, 15 and 20:

  • 10 SEER = 4,800 watts of electricity
  • 15 SEER = 3,200 watts of electricity
  • 20 SEER = 2,400 watts of electricity

This rating will change depending on the difference between indoor and outdoor temperature. Your air conditioner works best when the outdoor temperature is mild. It works harder when the thermometer climbs past 90.

Finding the Sweet Spot

As you can see, a 15-SEER AC uses 33 percent less energy than a 10-SEER AC. But a 20-SEER AC only reduces energy consumption by an additional 25 percent. Due to diminishing returns, the biggest energy savings occur when replacing an old unit with a brand new one. Swapping out a 20-year-old 5-SEER model with a standard 15-SEER model will cut your utility bill by an impressive 67 percent!

That’s not to say that you shouldn’t select a more efficient model. Higher-end units come with bells and whistles often lacking in standard models. Every home has a sweet spot that balances energy efficiency with the system’s upfront cost. Contact Texas Comfort Air at (512) 285-7182 to learn more about what’s best for your home.