Goodman GDH80804BN 80% AFUE 80000 BTU 2-Stage Downflow Gas Furnace

Advanced Heat Exchanger Design The GDH8 furnace employs a reliable dual-diameter tubular heat exchanger design. Aluminized steel is used for incredibly efficient heat transfer and a wrinkle-bend is applied to the tubes to enhance the heat exchanger’s dependability and longevity. Dualaver Technology Dualaver Technology allows GDH8 furnaces to begin operating at the lower stage for ideal efficiency. The control board uses historical data about the rate of temperature change in your home to decide whether the higher stage of heating is necessary. Quiet Comfort