SEER2 is the updated 2023 version of the Seasonal Energy Efficiency Ratio, reflecting new testing standards that better simulate real-world external static pressure. A higher SEER2 rating means the unit uses less electricity to provide the same amount of cooling, directly lowering your monthly utility bills. For maximum savings, many of our wall mount units feature SEER2 ratings that far exceed the federal minimums. When browsing our great deals and more, looking for high SEER2 units is the best way to ensure long-term ROI on your investment. We prioritize stocking high-efficiency Mitsubishi and Cooper&Hunter systems that lead the market in these metrics.