Boiler repair and replacement in Hamilton.

Natural gas heats just 22 of the 1,298 owner homes in ZIP 20158. Heat pumps and electric heat cover roughly half, propane a little under three in ten, and the boilers we’d meet burn propane from a tank by the house. Hamilton’s housing splits two ways, too: two in five owner homes date from 2000 or later, while nearly four in ten predate 1980 and hold most of its radiators and baseboard.

Loudoun County issues the building permits for boiler work in Hamilton, inside the town limits too. Since October 1, 2025, a replacement that keeps the same BTU rating in the same location doesn’t need submitted plans, which makes a like-for-like cast iron swap the simpler job. A condensing boiler, at $12,782 to $16,500 installed, changes the venting from the chimney to a plastic pipe through the wall or roof, a different mechanical setup.

Oil is still Hamilton’s third fuel, at close to one in five owner homes. When that equipment reaches the end, the choice we price is a propane boiler on the existing radiators or a heat pump, and with about half the town already on electric heat, plenty of neighbors have made the heat pump switch.

Hamilton’s winter is long. The Purcellville station, 2.6 miles away, averages 4,942 heating degree days a year, about 7 percent more than Dulles, and in January 2025 a local station read 5 below zero. A boiler that quits in that kind of cold leaves a house cold fast, which is the case for a fall tune-up at $69 a system. Clear the snow from around a plastic boiler vent after a storm, too.