90,000 BTU, 80% Efficiency, Two-Stage Burner, 3-Speed Blower, Upflow/Horizontal Application Gas Furnace

The Goodman GMH8 80% AFUE Two-Stage (Convertible), Multi-Speed Multi-Position Gas Furnaces feature a patented aluminized-steel tubular heat exchanger and durable Silicon Nitride Hot Surface Ignition system. This furnace is run-tested for heating or combination heating/cooling applications. With a heavy-gauge, reinforced, insulated steel cabinet and durable baked enamel finish, this unit can be installed in a variety of locations.
These furnaces are designed to be used with a single stage room thermostat. They are similar to the Two-Stage Variable Speed (GMV) models. These furnaces are capable of the following heating modes: two-stage burner- low stage to high stage based on an adjustable time set on the board (not controlled by the thermostat) ). The blower also has two speeds in the heating mode, low and high, and it will change speeds according to the high or low stages. Single Stage where the furnace will run as a standard furnace with one flame level and a single speed blower (Factory setting). The benefits are similar to the Two-Stage Variable Speed (GMV) models but these are Super-efficient with Ultra quiet variable speed circulator motor that gently ramps or down according to heating and cooling demands with enhanced dehumidification and energy savings during cooling months.
Features

• 10 Year Parts Warranty
• Lifetime Heat Exchanger Limited Warranty
• Patented TuffTube dual-diameter tubular heat exchanger with lifetime limited warranty plus10-year limited furnace replacement warranty
• Two-stage gas valve with revolutionary new convertible technology that allows installer to activate two stage operation with the flip of a dipswitch
• Silicon Nitride igniter with patented adaptive learning control for maximum igniter life
• Furnace control board with self-diagnostics, color coded low-voltage terminals and provisions for electronic air cleaner and 24 volt humidifiers
• Control board stores the last five diagnostic codes in memory; simple push-button activation outputs the fault history to a flashing red LED
• Low constant fan allows homeowner to activate the low heat speed to efficiently circulate air throughout the home
• Self-adjusting feature automatically adjusts furnace to high or low stage based on outside temperature without an outdoor temperature sensor