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Understanding Common HVAC and Water Heating Unit Ratings

July 15, 2026

If you’ve ever looked closely at your HVAC or water heating units, you may have noticed groupings of letters and numbers that look randomly slung together. Some of what you may see are actually HVAC and water heating unit ratings, which are important indicators of how every single heating, cooling, or water heating unit works and operates.   Here we’ll decode some of the common HVAC and water heating unit ratings, how they impact energy efficiency, and what they mean for your home.  What are HVAC and water heating unit ratings?  Every heating and cooling unit comes with specific ratings…

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