Furnace replacement in Bristow.

Of the 9,619 homes the Census counts in 20136, 5,558 were built from 2000 through 2009, so Bristow’s furnaces mostly share a birth decade. Their outdoor units don’t always. A condenser made before 2010 most likely holds R-22, which stopped being produced in 2020, and once one of those sprang a leak, the usual fix was a new condenser and coil rather than a refill. A Linton Hall house that went through that has a cooling side under ten years old sitting beside, and on top of, a builder’s gas furnace that’s now around twenty.

Those houses are the reason to price a furnace by itself. The newer coil rides on the furnace cabinet; the replacement must match that cabinet’s width and deliver the airflow the outdoor unit was sized for. The tech reads the condenser’s label, its year, tonnage and refrigerant, before writing anything. A decade younger than the furnace and cooling fine, it stays put. If its label carries the build year too, look at a matched pair: $8,898 to $23,000 installed.

Your gas bill decides part of the math. Washington Gas says some areas of Prince William County are Columbia Gas territory. Both companies publish rebates for high-efficiency gas furnaces, each for its own customers, with the amount climbing in steps as the AFUE rating rises, and Columbia Gas adds that its rebate money is capped and handed out in the order requests arrive. Find the company name on the bill before choosing an efficiency, and have the AFUE written on the quote.

A high-efficiency furnace breathes through PVC: an exhaust pipe, often an intake beside it, out through a wall or the roof, plus a condensate line to a drain or a small pump. On a Victory Lakes house that pipe exits onto an exterior the Covenants Committee reviews, and owners may need to file an Application for Exterior Modification first, so ask the association early.