Traditional “power combustion” furnaces are 80-82% AFUE. Above 90% AFUE, a furnace is “condensing,” which means it recaptures some of the heat wasted in traditional systems by condensing escaping water vapor. An energy efficient furnace will not only help the environment but it will also save you a great deal of money, so make sure you consider purchasing an energy efficient furnace with a high AFUE percentage. In fact, if you have a 95% AFUE furnace, then for every $100 in heating costs, you could save about $23. As you can guess, the number refers to the AFUE efficiency rating of the furnace. 303-993-9060//www.premieraircolorado.com