Goodman GMH80804BN 80% AFUE 80,000 BTU 2-Stage Upflow Gas Furnace

Product Features Advanced Heat Exchanger Design Two-stage gas valve The GMH8 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. 110V Silicon Nitride igniter Dual$aver Technology Quiet four-speed direct-drive circulating blower motor Dual$aver Technology allows GMH8 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. Furnace control board with self-diagnostics Quiet Comfort