Goodman GR9T960603AN Gas Furnace vs Goodman GR9S800603BN Gas Furnace

The GR9T960603AN is the better furnace for most homes: its two-stage gas valve and nine-speed ECM blower hold steadier temperatures and use less fuel than the single-stage GR9S800603BN. The 80% unit is simpler and cheaper to install, especially where a standard vent is already in place, but it runs at full output every cycle and burns more gas over a season. Both are Goodman's builder-grade line, and owners and technicians consistently describe them as reliable when installed correctly, with the usual caveat that the warranty depends on professional installation and registration.

• Choose the Goodman GR9T960603AN if you want lower fuel use, quieter and steadier heating, or a compact cabinet that fits a tight mechanical closet.
• Choose the Goodman GR9S800603BN if your home already has a standard vent and your budget or install constraints favor a simple single-stage furnace.