Outside the fence, most houses with Fort Belvoir mail sit in Cook Inlet, and Fairfax County’s records date nearly all 256 of them to 2002 through 2004, each built with central air. An outdoor unit from those years most likely left the factory charged with R-22. Production of that refrigerant ended in 2020, so a leak gets topped off from a shrinking supply while the copper and the indoor coil keep aging. The federal energy department plans on about 18 years for a central AC in this climate. A builder original here is past twenty.
The county shows a gas connection at all 256 Cook Inlet lots, which is why an AC on its own is the usual job. The basement furnace keeps the heating, and the new condenser gets a new cooling coil that sits on top of that furnace and uses its blower. A furnace from the same week as the AC is just as old, though, so its label deserves a read before anyone quotes the condenser alone. Bigger detached houses often add an attic system for the top floor, priced as its own AC.
Cook Inlet’s 108 townhouses set the condenser in a small back yard or beside a deck, so the replacement has to fit the old one’s spot and keep its clearances. Then the paperwork. Fairfax County lists replacing a cooling system as mechanical permit work, and because new air conditioners run on the newer A2L refrigerants, the county also asks for an A2L refrigeration system certification with that permit. Swapping a 2003 R-22 unit means both. Ask the installer to name the new refrigerant, the permit and who files the certification, all on the written quote.
Backlick Road in Accotink is the other side of 22060. The county shows gas unavailable to 18 of its 19 lots, on houses it dates from 1900 to 2010, so a furnace with central air is the exception there. Without a gas line the cooling usually comes from a heat pump, and a worn out heat pump gets replaced as one, $8,499 to $21,650 installed. A propane furnace with an AC is the case for an AC-only swap. On post, The Villages at Belvoir keeps up the heating and cooling in family housing, some of it geothermal.