Seasonal Energy Efficiency Ratio (SEER) Ratings
Air conditioner efficiency is critical to your home’s comfort and the size of your summer electric bills. The higher the SEER rating, the more efficient the system. Higher efficiency air conditioning installations cost more up front but provide substantial operational cost savings and a more comfortable feel in your home.
The minimum SEER level in cooler northern states is 13 SEER, but 14 SEER for Dallas/Fort Worth and other parts of the southern and western United States. Some air conditioning equipment manufacturers offer AC units up to 25 SEER.
The chart below shows operational savings for SEER rating 10-21 compared to a baseline 8 SEER system. Most AC systems installed before Jan. 1, 2006, were 10 SEER or less. Since then, 13/14 SEER has been the minimum allowed. This SEER energy savings calculator allows you to see projected savings in dollars and percentages when comparing SEER ratings.
You are the best judge of what SEER rating is best for your home, weighing the operational versus installation costs. The difference in comfort or “feel” that a high-efficiency central air conditioning system provides is not quantifiable but is much greater than you may expect and well worth consideration.
That increased comfort comes from two important differences – two-stage or variable-speed compressors, plus variable-speed blowers. Single-stage equipment with lower SEER values is either running full-speed or it’s off. It cycles on and off more frequently, using more power for each startup while adding additional wear and tear on the equipment. It’s like flooring your car’s accelerator to pull away from a stop sign instead of applying power gradually.
Units with two-stage compressors (usually found at 17 SEER and higher) are designed to run at their lower speed about 80% of the time and kick into high-speed only when necessary. AC units of 18 SEER and up are available with variable-speed compressors that run only as fast as the cooling load demands.
Variable speed blower fans distribute the air through the duct system at higher speeds when more cooling is called for by the system. In addition to higher efficiency, variable-speed systems also run much more quietly.