Furnace replacement in Clifton.

Most of the furnaces in 20124 sit in the subdivisions off Springstone Drive and Union Mill Road. In the Census tract that covers them, 949 of 1,113 owner homes heat with natural gas, and nine houses in ten went up in the 1980s. A builder’s furnace from then would be near forty, so yours is most likely its replacement, and one from the 2000s is already into the fifteen to twenty years a gas furnace usually gets.

Keeping the air conditioner is what makes this a furnace-only job, and it works while the outdoor unit and the coil sitting on the furnace have years left. The new furnace has to fit that coil and move the right amount of air across it, so we check both before quoting. An R-22 label on the outdoor unit usually means it’s as old as the furnace, and then the pair together, $8,898 to $23,000, is worth pricing too.

Out on Clifton, Compton and Yates Ford Roads, in the tract that takes in the town and the five to ten acre lots around it, only a quarter of owner homes burn natural gas and about one in ten burns propane from a tank on the property. A propane furnace is the same furnace with its gas valve and burners set up for propane before anyone lights it. Check the tank gauge before install day: the new one gets lit and tested on that propane before we leave.

Inside the Town of Clifton the houses are older still: by the Census’s rough count, about half were built before 1940. There the vent is the part to settle first. A standard furnace can keep using the chimney; a high-efficiency one sends its exhaust out through plastic pipe, and a pipe through the clapboard of a house in the historic district changes the outside, which the Town’s FAQ puts in front of its Architectural Review Board. Where nothing else uses the chimney, that pipe can sometimes run up inside it instead.