GAS FURNACE 92.1% AFUE - 125.000 Btu/h - TWO STAGE - VARIABLE SPEED Up to 92.1% AFUE ENERGY STAR qualified Heating size range 50,000-125,000 Btuh 1-1/2 to 5-tons cooling capacity supported Crimp-Tite aluminized steel heat exchanger with 20-year limited warranty; 5-year limited warranty on components (see warranty certificate for details)