Furnace Replacement Cost in New Hampshire

Furnace replacement in New Hampshire costs $4,100 to $9,900 in 2026, though city-to-city prices vary quite a bit. Heating drives most HVAC spending in New Hampshire: its larger communities average 6,949 heating and 525 cooling degree days a year.

Furnace Replacement Prices in New Hampshire Cities

From 2020 through 2025, NOAA recorded 300 winter storm and ice events, 7 heat events, 15 extreme cold events and 213 hail reports in New Hampshire. Those are the days when emergency HVAC calls pile up.

When Replacement Makes Sense

• The furnace is 15 to 20 years old or more
• A repair quote runs past a third of the cost of a new unit
• Gas or electric bills keep climbing even though usage hasn't changed
• Some rooms stay cold, the burner short-cycles, or the ignitor keeps failing
• A tech found a cracked heat exchanger, or the CO detector has gone off

What Moves the Price

• AFUE rating: a basic 80% unit vs. a 96% condensing furnace
• BTU size, which should come from a Manual J load calculation
• Single-stage, two-stage or modulating gas valve
• New PVC venting if you move to a condensing model
• Permit and inspection fees, which the local building department sets
• Condition of the existing ductwork and any changes it needs

Common Questions