Understanding Air Conditioner Efficiency Ratings


Shopping for a new central air conditioner lacking a familiarity with air conditioner ratings is like going hiking barefoot. You’re not going to get very far. Ratings that show the cooling efficiency of an air conditioning system (in effect, how well the system converts electricity into cooling) will help you get the right AC for your San Diego-area home.


About SEER Ratings


The most common residential central cooling system in Southern California (and the U.S. as a whole) is the split-system AC or heat pump. It has one component (the air handler/evaporator coil) inside the house and another (the condenser/compressor) outside. The main efficiency rating applied to split-systems is Seasonal Energy Efficiency Ratio (SEER). The number — running from 13 to 25 in the U.S. — is calculated by dividing cooling output by the electrical power that goes into the equipment. The higher the number, the more efficient the AC or heat pump.


What Does Energy Star Mean for Air Conditioners?


Manufacturers in California are prohibited from selling split-system ACs with SEER numbers below 14. Heat pump ACs must have at least SEER 15. In order to qualify for the federal government’s energy-efficiency credential, the Energy Star, a split system air conditioner and heat pump must boast SEER 15 or above.

The higher efficiency does cost money, however, with incremental increases in SEER amounting to hundreds of dollars. A homeowner shopping for a new central AC should consider how much use they expect to get out of their new cooling system. A family that runs the AC constantly and expects to live in the same home for the foreseeable future should consider investing in a high-SEER AC or heat pump. Over time, the lower operating costs will pay for the extra upfront cost. However, someone who doesn’t plan to stay in the same home more than a few years, or is out of town a lot, is probably better off with a low-end SEER system. Consult with your trusted HVAC contractor before deciding on a replacement AC system.



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