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80% Gas Furnace

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At just 34-1/2" high, our 80% space-saving furnace is ideally suited to both new construction and replacements - models can fit into the space of virtually any furnace being replaced, including attics, crawl spaces and utility closets. Contractors will appreciate not just the small size, but also the number of installation options, including left- or right-side gas, and left- or right-side electric connections. Because of the small size, it's easy to handle, fitting easily through most doors and hallways.

AFUE ratings of 80% mean that nearly all the heat generated by the furnace is used to heat the home. In this time of soaring fuel prices, better utilization of natural resources can mean significant dollar savings.

The GUH Upflow/Horizontal Series comes in capacities ranging from 45,000 BTUH to 126,000 BTUH, while the GDD Downflow Series is available in 54,000 to 126,000 BTUH capacities.

Completely assembled, the furnace is ready for installation with a color-coded wiring harness and quick connect fittings. The integrated solid state control board speeds installation. Maintenance and servicing is easy to do with readily accessible components. Two-piece doors remove quickly and door screws are secured to the doors so they can't be lost after they're loosened. Diagnostic lights make it easy to troubleshoot operation.

80% furnaces are backed by a 20 year warranty on the aluminized steel heat exchanger and a 12 year warranty on other components. (Limitations apply; see printed warranty or website for details)


  • Induced Draft Blower—Designed specifically to work with the tubular heat exchanger, it pulls hot combustion gases through the exchanger until the burner cycles off; heated air is locked in while cold air is locked out
  • In-Shot Burner—Engineered to deliver to most efficient air/gas mixture, it allows heat to be generated efficiently
  • Tubular Heat Exchanger—The heart of the furnace, the heat exchanger is made of heavy gauge aluminized steel, and carries a 20-year warranty
  • Hot Surface Igniter—Quiet and automatic, it eliminates the need for a standing pilot light for improved efficiency
  • Multi-Speed Direct Drive Blower—Delivers warm, filtered air through the ductwork to each room and also covers a wide range of cooling capacities; switches on PCB make it easy to select motor speed
  • Integrated Control Board—Combines all controls and functions into one board for easy installation, and is designed to accept options such as an electronic air cleaner

95% Single Stage Gas Furnace

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Two heat exchangers make this one of the most efficient furnaces on the market today. Using 95% or more of the heat output from each cubic foot of gas, this furnace produces not just greater comfort, but also significant fuel savings.

At only 34-1/2" in height, the furnace is ideal for renovations and replacements, fitting in virtually any space where a furnace was previously installed, including basements and utility closets.

The furnace comes assembled and prewired, with a color-coded wiring harness and quick connect fittings. An integrated control board simplifies hook-ups, and all components are easy to reach. Because of its small size, the furnace is easy to handle, fitting through doors, halls and stairways.

The front panel door is easy to remove to access the filter, encouraging regular filter replacement

The blower compartment has a sealed insulated door, while a sealed vestibule reduces burner and inducer sound levels for clean, efficient, quiet combustion.

The primary and secondary heat exchangers are covered by a limited lifetime warranty; other components are covered for 12 years. (Limitations apply; see "Warranty" for details.)


  • Draft Inducer—Specifically designed for the tubular heat exchanger, it pulls hot combustion gases through the exchanger; heated air is locked in while cold air is locked out
  • In-shot Burner—Engineered to provide the most efficient air/gas mixture for combustion, the design requires no manual adjustments to regulate the mix
  • Primary Heat Exchanger—The patented tubular design is resistant to corrosion and thermal fatigue, and it is covered by a lifetime warranty
  • Secondary Heat Exchanger—Unique heat recovery coil extracts additional heat (which woud be lost by less efficient furnaces); stainless steel construction has a lifetime warranty
  • Hot Surface Ignition—Silicon nitride type igniter is quiet and automatic, eliminating the need for a standing pilot light
  • High Efficiency Blower—Three-speed blower delivers warm air throughout the house quietly and efficiently; direct drive system has no belts or pulleys to wear out
  • Integrated Furnace Control—Controls are integrated into one board for fast, easy installation; features on-board diagnostics with easy to recognize fault codes

95% Two Stage Gas Furnace 

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Our two stage furnace is designed for maximum convenience and optimum comfort. A conventional single stage furnace operates at high heat until the thermostat is satisfied, then shuts off until there's a demand for heat again. As a result the furnace is constantly cycling on and off. But with a two stage furnace, these temperature swings are virtually eliminated and your home stays at the comfort level you select.

Most of the time, a two stage furnace operates in the low stage, delivering a gentle yet steady flow of heated air. When the weather turns really cold, the furnace automatically shifts into the high stage, providing the extra heat needed to keep the home at the desired comfort level. Whenever the furnace is in the low stage, energy is saved because the burner flame is smaller and the blower fans runs at a slower speed. Even in the high stage, with AFUE rating of 95%, utility costs are being saved.

The ECM variable speed blower motor adjusts the blower speed to deliver the airflow required by the system, resulting in more even temperatures than a single speed motor can provide. And because air is constantly being drawn across the filter, indoor air quality and humidity control are enhanced..

The primary and secondary heat exchangers are covered by a limited lifetime warranty; other components are covered for 12 years. (Limitations apply; see "Warranty" for details)


  • Quiet Operation—Sealed door and cabinet insulation locks in heat and sound; sealed vertibule reduces burner and inducer sound levels; ECM blower motor makes this one of the quietest furnaces on the market
  • Extraordinary Efficiency—Two heat exchangers deliver 95%+ of the heated air to the home; the ECM blower motor may give up to 1 SEER point gain in cooling efficiency
  • ECM Blower Motor—Runs at a variety of speeds to match the load demand, for efficiency and quiet operation; constant airflow through a wide vareity of ductwork conditions reduces temperature stratification while improving indoor air quality
  • Hot Surface Igniter—Silicon nitride type igniter is automatic, eliminating the need for a standing pilot light
  • Designed for Long Life—Primary heat exchanger is made of heavy gauge aluminized steel and secondary heat exchanger is made of stainless steel; cabinet is steel with corosion resistant finish
  • Thermostat—Can be used with either a single or two-stage thermostat; two stage is recommended for optimal efficiency (not included with furnace)



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