Tell us about the job
Takes about a minute. No obligation.
A contractor quoting a furnace installation in Strafford County has to size the unit for a burner that runs hard and rests little. Homes in Strafford County, NH run heat about eight months a year, from October through May. The heat exchanger, the ignition system, and the burner assembly carry that load every year, and a unit that is undersized or installed without a proper load calculation will show degraded components well before the end of its rated service life. Tight duct sealing and correct airflow matter here in a way they do not in places where the system spends most of the year off.
Ductwork sized and routed for equipment that is no longer in the house does not automatically fit what a contractor brings in to replace it. Half the homes in Strafford County, New Hampshire were built in 1979 or earlier (2020-2024 ACS 5-year). That spread across the housing stock means a contractor quoting a furnace installation has to treat the existing duct runs as a variable, not a given. Where the trunk lines are undersized for today's airflow demands, or where the layout creates pressure imbalances a new unit will amplify, the ductwork becomes a line item before the furnace itself is priced. The electrical service gets the same look, since the draw of current equipment does not always match what the panel was set up to carry.
What Gets Installed With a New Furnace
The furnace itself sits in the basement, utility room, or crawlspace and is the core unit a contractor places first. Attached to it is the flue or exhaust pipe, which runs from the unit to an exterior wall or up through the roof to carry combustion gases out of the house.
The air handler and blower assembly, housed inside the furnace cabinet, push conditioned air into the supply plenum at the top of the unit. The plenum is the sheet-metal box that transitions the furnace output into the duct runs, and it gets fitted to match the new unit's dimensions. A contractor also installs the thermostat, which mounts on an interior wall and gives the household control over the system.
The drawing shows a general layout of these components, and a licensed contractor determines exactly how each one applies to your house.
Find a contractor in Strafford CountyStrafford County by the Numbers
97 severe weather events were recorded in Strafford County, New Hampshire between 2015 and 2024.
NOAA National Centers for Environmental Information, Storm Events Database, bulk CSV export, events 2015-01-01 through 2024-12-31.Half the homes in Strafford County, New Hampshire were built in 1979 or earlier (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesStrafford County, New Hampshire holds 56,609 housing units (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesOwners occupy 67.1% of the occupied homes in Strafford County, New Hampshire (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesFurnace Installation Rules for Strafford County, New Hampshire6 codes, standards, and licensing rules
What the Installation Actually Looks Like
Non-weatherized gas furnaces manufactured on or after November 19, 2015 must reach 80.0 percent AFUE.
Non-weatherized oil-fired furnaces manufactured on or after November 19, 2015 must reach 83.0 percent AFUE.
Mobile home gas furnaces manufactured on or after November 19, 2015 must reach 80.0 percent AFUE.
Non-weatherized gas furnaces manufactured on or after December 18, 2028 must reach 95.0 percent AFUE, up from the 80.0 percent minimum that applies to units manufactured before that date.
Licensing Rules for Strafford County, New Hampshire
New Hampshire's mechanical licensing board issues nine credentials — hearth system, four fuel gas endorsements, domestic appliance technician, and master, journeyman and apprentice plumber — and a licensee may not work outside the specialty their licence names. None of the nine is an HVAC licence.
New Hampshire does not license HVAC as a trade, and says so where it matters: the plumbing licence expressly does not reach a person installing heating, cooling, air conditioning or domestic water heating systems, whether solar, oil, gas or electric. The gas piping on a gas-fired system is a separate matter and needs a fuel gas fitter licence.
Severe Weather Events in Strafford County
Strafford County's weather puts real stress on heating equipment, and a furnace that sits through years of hard conditions carries a different workload than one in a mild climate. How often that stress hits shapes what a contractor installs and how they size it.
97 severe weather events, 2015–2024. Source: NOAA National Centers for Environmental Information, Storm Events Database.