How each one works
A gas furnace burns natural gas to create heat and blows it through your ducts; it needs a separate AC for cooling. A heat pump uses refrigerant to move heat, outside in summer, inside in winter, so one system does both jobs without combustion.
Side by side
| Factor | Heat pump | Gas furnace |
|---|---|---|
| Heats & cools? | Both, in one system | Heating only (needs separate AC) |
| Fuel | All-electric | Natural gas |
| Efficiency rating | SEER2 + HSPF2 (very high) | AFUE (up to ~98%) |
| Deep-cold heat | Strong (cold-climate models) | Very strong |
| Upfront cost | Higher (replaces AC + heat) | Lower (furnace alone) |
| Rebates / credits | Often qualifies | Limited |
| Typical lifespan | 12 to 15 years | 15 to 20 years |
| Best for | Efficiency, all-electric homes, rebates | Cheap gas, harsh winters, lowest upfront |
Efficiency & operating cost
Heat pumps are rated by SEER2 and HSPF2; furnaces by AFUE. Which is cheaper to run depends on your local electricity-vs-gas prices, there's no universal winner, which is exactly why we model it for your home.
Cold-weather performance in Greater St. Louis
Our winters include genuine cold snaps, not just mild chill. Modern cold-climate heat pumps hold up far better in freezing temperatures than older models. For homeowners who want furnace-style heat on the coldest nights, a dual-fuel system lets a gas furnace take over automatically, see how dual-fuel works and dual-fuel vs. heat-pump-only.
Humid summers still matter
Whichever heating path you choose, cooling and dehumidification still have to handle sticky Missouri summers. A heat pump handles both seasons in one outdoor unit; a furnace still needs a properly sized central AC (or ductless zones) beside it.
Upfront cost & incentives
A furnace usually costs less upfront on its own, but a heat pump replaces both heating and cooling and frequently qualifies for Ameren rebates and manufacturer incentives that close the gap.
The bottom line
Choose a furnace for the lowest upfront cost and maximum heat where gas is cheap; choose a heat pump for efficiency, all-electric operation, and incentives; choose dual-fuel to get both. We'll help you decide, or size a heat pump for your home.