Furnace and AC replacement in Marshall.

The median owner home in 20115 was built in 1986, and more than a third of the ZIP’s homes went up between 1980 and 1999. A house that age is long past its first furnace and air conditioner, and the pair it has now often went in together. Two machines installed the same year age together, and because the outdoor unit’s coil rests on the furnace, replacing them a year apart opens that closet twice.

A furnace and an air conditioner is the less common setup here: electricity heats close to two owner homes in three, which in Marshall mostly means a heat pump and an air handler, a different job with its own price. Here the pair mostly means the propane houses, 424 of the 2,109 owner homes, the handful on natural gas, and some of the 160 that heat mainly with wood and keep a furnace behind the stove.

Where you land in the range follows the house, and Marshall spans both ends. A cottage on Salem Avenue or a story-and-a-half frame house on Anderson Avenue takes a small system, sized to what its ducts can carry if they were fitted long after it was built. The bigger detached houses on acreage around the village often run two systems, one for the main floors and one for the bedrooms, each priced as its own pair.

Marshall built less after 2000: 436 homes went up in that decade and fewer than 200 in the next. Where one of those houses still runs the furnace and air conditioner it was built with, the pair is near or past twenty, and the first failure should bring a price for both. If it might still be a repair, the diagnostic visit is $99.