Furnace replacement in Nokesville.

Roughly a third of the owner homes in 20181 burn propane or natural gas for heat, and propane is ahead, 597 homes to 459 in the Census count. In the village around Aden Road the gap is wider, about three propane homes for every natural gas one. So a Nokesville furnace swap is more often a propane job than a gas one, and the replacement gets its propane setup and a leak check before its first fire.

Keeping the outdoor half only pays when it has years left in it. Out here it’s frequently a heat pump rather than a straight air conditioner, doing most of the heating while the propane furnace waits for the hard freezes. Leave it in place and the new furnace takes on two duties: hold up the indoor coil the heat pump pushes refrigerant through, and take over the heating at the outdoor temperature the thermostat is set to hand it off. That handoff gets reprogrammed for the new furnace.

Over a third of the ZIP’s homes date from the 1970s and 1980s, which makes the furnace in one of them most likely its second or third. The 904 built from 2000 through 2009 are where original builder furnaces hang on, now 17 to 26 winters old, and a propane furnace that only lights on cold nights has still aged a full winter every year.

Village houses run older, with a 1970 median for owner homes. In a house that age the furnace may sit in a cellar corner, a crawlspace or a closet off the kitchen, venting through a metal flue up through the roof. A high-efficiency replacement exhausts through plastic pipe, most often through a side wall, and produces water that has to reach a floor drain or a condensate pump. Where that pipe exits and where that water goes belong in the written quote.