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80,000 BTU Downflow Furnaces

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Goodman 80% AFUE Gas Furnace 80,000 BTU 17.5"W Cabinet Downflow/Horizontal

SKU: GD9S800804BN
Product ID: 100973
Original price $0.00 - Original price $0.00
Original price $0.00
$1,460.00
$1,460.00 - $1,460.00
Current price $1,460.00

Product Details Goodman R32 80% AFUE Gas Furnace 80000 BTU 17.5" Wide 1600 CFM Downflow GD9S800804BN The Goodman GD9S800804BN gas furnace delivers...

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Goodman 96% 80,000 BTU Gas Furnace Two Stage 17.5"W Downflow/Horizontal

SKU: GD9T960803BN
Product ID: 100920
Original price $0.00 - Original price $0.00
Original price $0.00
$2,560.00
$2,560.00 - $2,560.00
Current price $2,560.00

Product Details Goodman 96% 80,000 BTU Gas Furnace Two Stage 17.5"W Downflow/Horizontal GD9T960803BN The Goodman GD9T960803BN gas furnace offers p...

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Goodman 96% AFUE Gas Furnace 80,000 BTU 21"W Nine-Speed Downflow/Horizontal

SKU: GD9S960804CN
Product ID: 100915
Original price $0.00 - Original price $0.00
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$2,228.00
$2,228.00 - $2,228.00
Current price $2,228.00

Product Details Goodman R32 96% AFUE Gas Furnace 80000 BTU Nine-Speed Downflow/Horizontal GD9S960804CN The Goodman GD9S960804CN is engineered to p...

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ACiQ 80% AFUE 80K BTU Gas Furnace Low NOx 17.5"W Two-Stage Downflow/Horizontal

SKU: AQ-GD9T800804BX
Product ID: 92505
Original price $0.00 - Original price $0.00
Original price $0.00
$1,375.00
$1,375.00 - $1,375.00
Current price $1,375.00

Product Details ACiQ 80% AFUE 80,000 BTU Gas Furnace Low NOx 17.5"W Downflow/Horizontal AQ-GD9T800804BX The ACiQ AQ-GD9T800804BX is a high-effici...

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Goodman 97% AFUE 80K BTU Furnace Variable Speed 17.5"W Downflow/Horizontal

SKU: GDVM970803BN
Product ID: 101408
Original price $0.00 - Original price $0.00
Original price $0.00
$3,463.00
$3,463.00 - $3,463.00
Current price $3,463.00

Product Details Goodman 97% AFUE 80K BTU Variable Speed Modulating Gas Furnace 17.5" Width GDVM970803BN The Goodman GDVM970803BN is part of Goodma...

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Goodman 80% AFUE 80K BTU Gas Furnace Low NOx 21"W Two Stage Downflow/Horizontal

SKU: GDVT800805CX
Product ID: 101425
Original price $0.00 - Original price $0.00
Original price $0.00
$2,381.00
$2,381.00 - $2,381.00
Current price $2,381.00

Product Details Goodman 80% AFUE 80,000 BTU Two Stage Gas Furnace 21" Downflow/Horizontal GDVT800805CX The Goodman GDVT800805CX Gas Furnace is pa...

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Goodman 80% AFUE 80K BTU Gas Furnace Low NOx 17.5"W Two Stage Downflow/Horizontal

SKU: GDVT800803BX
Product ID: 101424
Original price $0.00 - Original price $0.00
Original price $0.00
$2,260.00
$2,260.00 - $2,260.00
Current price $2,260.00

Product Details Goodman 80% AFUE 80,000 BTU Two Stage Gas Furnace 17.5" Downflow/Horizontal GDVT800803BX The Goodman GDVT800803BX Gas Furnace is ...

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Goodman 96% AFUE 80K BTU Furnace Variable Speed 21"W Downflow/Horizontal

SKU: GDVT960804CN
Product ID: 101415
Original price $0.00 - Original price $0.00
Original price $0.00
$3,140.00
$3,140.00 - $3,140.00
Current price $3,140.00

Product Details Goodman 96% 80K BTU Gas Furnace Variable Speed Downflow/Horizontal 21"W GDVT960804CN The Goodman GDVT960804CN is a high-efficiency...

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Goodman 97% AFUE 80K BTU Furnace Variable Speed 21"W Downflow/Horizontal

SKU: GDVM970804CN
Product ID: 101409
Original price $0.00 - Original price $0.00
Original price $0.00
$3,511.00
$3,511.00 - $3,511.00
Current price $3,511.00

Product Details Goodman 97% AFUE 80K BTU Gas Furnace Variable Speed Downflow/Horizontal GDVM970804CN The Goodman GDVM970804CN is a premium gas fur...

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Goodman 80% AFUE 80K BTU Gas Furnace Low NOx 21"W Two-Stage Downflow/Horizontal

SKU: GD9T800805CX
Product ID: 100982
Original price $0.00 - Original price $0.00
Original price $0.00
$1,626.00
$1,626.00 - $1,626.00
Current price $1,626.00

Product Details Goodman R32 80% AFUE Gas Furnace 80K BTU Two-Stage 21"W Low NOx Downflow GD9T800805CX The Goodman GD9T800805CX is a reliable, high...

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Goodman 80% AFUE 80K BTU Gas Furnace Low NOx 17.5"W Two-Stage Downflow/Horizontal

SKU: GD9T800804BX
Product ID: 100981
Original price $0.00 - Original price $0.00
Original price $0.00
$1,575.00
$1,575.00 - $1,575.00
Current price $1,575.00

Product Details Goodman 80% AFUE 80,000 BTU Gas Furnace Low NOx 17.5"W Downflow/Horizontal GD9T800804BX The Goodman GD9T800804BX is a high-effici...

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Goodman 80% AFUE 80K BTU Gas Furnace Multi-speed Low NOx 21"W Downflow/Horizontal

SKU: GD9S800805CX
Product ID: 100975
Original price $0.00 - Original price $0.00
Original price $0.00
$1,521.00
$1,521.00 - $1,521.00
Current price $1,521.00

Product Details Goodman R32 80% AFUE Gas Furnace 80K BTU 21"W Low NOx Downflow/Horizontal GD9S800805CX The Goodman GD9S800805CX is a high-efficien...

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Goodman 80% 80K BTU Gas Furnace Low NOx 17.5"W Cabinet Downflow/Horizontal

SKU: GD9S800804BX
Product ID: 100974
Original price $0.00 - Original price $0.00
Original price $0.00
$1,467.00
$1,467.00 - $1,467.00
Current price $1,467.00

Product Details Goodman R32 80% AFUE Gas Furnace 80K BTU 17.5" Wide Low NOx Downflow GD9S800804BX The Goodman GD9S800804BX is an energy-efficient ...

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An 80,000 BTU downflow furnace is designed for specific architectural setups where the ductwork is located below the unit, such as in a crawlspace installation or a slab foundation home. This downflow configuration pushes air downwards into the supply ducts, requiring a unit engineered to handle that specific airflow direction. Whether you are looking for a standard-efficiency 80% AFUE model that uses existing metal venting or a high-efficiency 96% AFUE condensing furnace that requires PVC venting, our inventory covers all bases.

These units are ideal for mid-sized homes, delivering consistent warmth with a reliable natural gas furnace. Performance and comfort are paramount in our selection. Many of our premium models feature two-stage heating and an energy-efficient ECM blower motor. Unlike a single-stage burner that operates at full blast, a two-stage gas furnace can run at a lower capacity to maintain temperature, providing quieter operation and more even heat distribution.

For those prioritizing energy savings, an Energy Star-certified unit with a high AFUE rating ensures that more of your fuel is converted into heat, lowering utility bills. Each 80,000 BTU downflow furnace is equipped with a durable aluminized-steel heat exchanger and a self-diagnostic control board, making maintenance straightforward and extending the equipment's lifespan.

Factors To Consider When Choosing the Right 80,000 BTU Downflow Furnace for Your Needs

  • Efficiency Levels: Choose between an 80% AFUE unit for a cost-effective replacement that uses a chimney or a 96% AFUE condensing furnace for maximum energy savings and PVC venting.

  • Heating Stages: Select a single-stage burner for basic, reliable heating, or upgrade to two-stage heating for enhanced comfort and reduced temperature swings.

  • Fuel Flexibility: While most units ship as natural gas furnaces, we offer a propane conversion kit for customers who need to run their systems on liquid propane (LP).

  • Installation Fit: Verify the cabinet width and height to ensure the new 80,000 BTU downflow furnace fits your existing plenum and space, especially for tight closets or mobile home furnace replacements.

  • Warranty Coverage: Invest with confidence, knowing our Goodman and ACiQ gas furnaces come with a strong factory warranty on the heat exchanger and parts.

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FAQ

What size house does an 80,000 BTU downflow furnace heat?

An 80,000 BTU downflow furnace is typically suitable for homes ranging from 1,500 to 2,000 square feet, depending on your climate zone and insulation levels. It is important to perform a load calculation to ensure the BTU input is correct for your space.

What is the difference between 80% and 96% AFUE?

The AFUE rating measures efficiency. An 80% AFUE gas furnace converts 80% of the fuel to heat and wastes 20%, typically venting through a metal flue. A 96% AFUE unit is a condensing furnace that captures more heat, wasting only 4%, and requires PVC venting due to the cooler exhaust gases.

Can I convert these furnaces to propane?

Yes, while they are sold as natural gas furnaces, most models can be converted using a specific propane conversion kit. This is a common solution for rural homes or areas without natural gas lines.

What is a downflow configuration?

A downflow configuration means the furnace draws air from the top and blows heated air out the bottom. This is common in homes with ductwork in the floor, such as those built on a concrete slab or with a crawl space.

Why choose a furnace with an ECM blower motor?

An ECM blower motor (Electronically Commutated Motor) is more energy-efficient and quieter than a traditional PSC motor. It can adjust its speed to maintain optimal airflow, improving overall efficiency and comfort from your 80,000 BTU downflow furnace.

Do these furnaces meet low NOx emission standards?

Many of our Goodman furnace and ACiQ gas furnace models are designed to meet low NOx emissions requirements in specific states to comply with strict environmental regulations. Check the product specifications to confirm compliance for your area.

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