Furnace / Boiler Efficiency Upgrade
Work out the savings and payback of replacing an old furnace or boiler with a higher-AFUE model, free online.
About this calculator
A heating system's AFUE is the share of fuel energy that becomes useful heat. Fuel use scales with 1 ÷ AFUE, so replacing an 65% unit with a 95% unit cuts fuel use by about 32%. Enter your current annual heating bill to estimate the yearly saving.