Two-Stage Furnaces: Find Out How They Do Their Job by Mike Rampey | January 9, 2014January 9, 2014 According to the U.S. Government’s Lawrence Berkeley National Laboratory, 70 percent of American homes are heated by furnaces. Of those, the majority are the single-stage variety – which are likely […]Read More Filed Under: Furnaces Tagged With: Broken Arrow– energy efficiency– furnace sizing– modulating furnace– Oklahoma– Tulsa– Two-Stage Furnaces