Goodman 40,000 BTU 80% AFUE Single-Stage Gas Furnace Upflow/Horizontal 14" Cabinet R-32

Dependable heating for small homes — proven Goodman quality at the most accessible price point. The Goodman GR9S800403AN delivers 40,000 BTU of single-stage heating at 80% AFUE in the slimmest 14" upflow cabinet available — the smart, no-nonsense choice for small homes, condos, and tight installation spaces that need reliable warmth without overpaying for efficiency they don't need. Straightforward, durable, and backed by one of the best warranties in the industry — this is affordable heating done right.

Why You'll Love It:

• 80% AFUE efficiency — converts 80 cents of every energy dollar into heat, keeping operating costs predictable without overpaying for efficiency ratings designed for larger or colder applications
• 40,000 BTU input / 32,000 BTU output — ideal heating output for small homes, condos, and apartments without oversizing or wasted capacity
• Single-stage operation with 9-speed ECM blower motor — steady, even airflow throughout your home with quieter operation and better humidity control than older PSC motor units
• Upflow / horizontal installation — flexible placement in basements, closets, or utility rooms to suit your home's layout
• Ultra-slim 14" cabinet — the narrowest cabinet in the Goodman GR9S80 lineup, compatible with 1-2 ton R-32 cooling systems — fits where other furnaces simply won't
• Heavy-duty aluminized-steel tubular heat exchanger — engineered for long-lasting durability and efficient heat transfer with wrinkle-bend technology for added dependability
• Silicon nitride igniter — more durable than older hot surface igniters, reducing maintenance calls and replacement costs over the life of the unit
• Self-diagnosing control board — acts like a "check engine light" for your furnace, pinpointing issues fast and cutting service time and costs
• LP convertible — easily field-converted to propane with optional kit, giving you fuel flexibility for your home
• Metal flue venting required — straightforward installation using standard metal duct for safe, code-conforming exhaust
• R-32 compatible — future-ready refrigerant support for pairing with modern R-32 cooling systems
• AHRI Certified and ETL Listed — independently verified for safety and performance
• Made in the USA — designed, engineered, and assembled domestically

⚠️ Metal venting required — this is an 80% AFUE furnace and requires metal flue venting, not PVC.

Specs:

• Input: 40,000 BTU | Output: 32,000 BTU
• AFUE: 80%
• Cabinet Width: 14"
• Stages: Single
• Blower Motor: 9-Speed ECM
• Fuel Type: Natural Gas (LP Convertible)
• Installation: Upflow / Horizontal
• Venting: Metal
• Voltage: 115V
• Compatible Cooling: 1-2 Ton R-32 Systems

Warranty: 10-year limited parts + lifetime heat exchanger warranty with online registration within 60 days of installation.