High efficiency is a phrase tossed around plenty in the world of home services. People are often laser-focused on getting appliances labeled as “high-efficiency.” Thankfully, there are government regulations about efficiency that make it easier to identify when a product meets the criteria for improved energy consumption. For electrical products, this is the ENERGY STAR label, which is determined by the US Department of Energy.
But when we talk about high-efficiency air conditioners, we’re referring to appliances that go beyond the ENERGY STAR requirement. For a central AC to receive the ENERGY STAR label, it must have SEER (the standard efficiency rating for air conditioners and heat pumps) of 15 or more. But there are central ACs with SEER up to 25. In general, if an air conditioner has SEER greater than 18, it’s considered “high efficiency.” A standard for many high-efficiency systems is 20–22 SEER.
Do you use a gas 
This is one of the long-running troubles that multi-story homes experience. Heat rises, so when trying to heat a two-story home, heat moves up to the second floor and begins to concentrate there. It’s natural during the winter season for the upper floor to become too stuffy whenever the furnace is on for long enough.
Look, we don’t expect every homeowner to understand precisely how it is that their air conditioning systems work. The reason for this is quite simple—we’d have to find another industry in which to make our living, and you can’t teach some old dogs new tricks! All joking aside, though, we do believe that it is in the best interest of homeowners everywhere to have a basic understanding of the way in which their air conditioning systems work.
Here in Colorado, we depend on our heaters a lot. Winters are cold and snowy, and your heating system is the only thing standing between you and extreme discomfort throughout the 
