A Manassas address can mean the City of Manassas, the City of Manassas Park or Prince William County. Each has its own permit office. Inside the City, swapping an outdoor unit that burns neither gas nor oil is on the no-permit list, while a first central air system in a house that never had one is mechanical permit work. The county skips the permit for the same type of condenser going back in the same spot. Manassas Park answers to its own building office.
The City splits almost evenly, about half its owner homes on gas and half on electricity, and in the electric half the unit outside is usually a heat pump, a different replacement. The gas half, and a little over half the county side, cool with a stand-alone air conditioner whose coil rides on the furnace. Loch Lomond is the most AC-only corner, about three owner homes in four on gas.
The City’s houses center on a 1985 median, and one that age has usually traded away its original condenser; if the second one went in before 2010, its refrigerant is likely R-22, whose production ended in 2020. On the county side the ages spread out: Sudley’s median is 1977, so its condensers are past their second round, while Independent Hill, median 2000, still has builder units getting old.
Inside the City, the electric company is the City, and its Load Management program puts a switch on an enrolled central air conditioner to cycle the compressor during summer peaks. If your old condenser carries one, ask the City what happens to the switch and your enrollment. Downtown, in the largest historic district, the guidelines want outdoor HVAC equipment somewhere unobtrusive or screened by plantings or a fence, so a condenser headed for a new spot there is a talk with City staff first.