AFUE typical bands by system type

Typical AFUE bands by system type — labeled typicals for planning, not a manufacturer spec sheet. Use the exact AFUE from your unit's nameplate or quote in the furnace-cost and AFUE-savings tools.

System typeTypical AFUE
Old / non-condensing gas0.56–0.70
Standard gas0.80–0.83
Condensing gas0.90–0.98
Oil furnace0.80–0.90
Electric resistance1.00

Labeled typicals for planning — use the exact AFUE from your unit's nameplate or quote.