Open 24/7 for emergencies
Oakton boilers mostly burn gas and live in its older houses: $99 keeps one tuned, $9,900 to $16,500 replaces it.
Price range
$9,900-$16,500
8yrs @ 7.99%
$140/mo
15yrs @ 9.99%
$106/mo
Monthly figures on the starting price, the whole price financed, on approved credit. The lender sets the final terms. How financing works
Get your price in writing
Send this and the office calls or texts you back to set a time.
We’ll call or text this number about your request. By sending it you agree to our terms and privacy policy.
Rather talk now? (703) 997-9757
5.0 stars across 1,132 reviews
Two of our heating technicians in a Northern Virginia basement. The same team tunes up, repairs and replaces boilers.
Licensed and insuredVirginia Class A contractor #2705192276
24/7 emergency serviceOften same-day, and we will tell you honestly when we can get there.
Our own HVAC installersA dedicated heating and cooling team, separate from our plumbers
Price in writing firstYou see every option priced before anything is ordered
What it costs
A new boiler runs $9,900 to $16,500 installed, the range of our own boiler replacements; a condensing or combi boiler lands at $12,782 to $16,500. A tune-up is $99 a system.
High-efficiency condensing boiler or combi boiler, installed
$12,782 to $16,500
or $213/mo at 0% APR for 60 months
Cast iron boiler on the chimney, replaced like for like, installed
$9,900 to $13,690
or $165/mo at 0% APR for 60 months
Boiler tune-up, one system
$99
Boiler repair diagnostic visit
$99
Monthly figures: 60mo @ 0% APR on each starting price, the whole price financed, on approved credit. Longer plans lower the payment and cost more in total. The lender sets the final terms. How financing works
A repair starts with the $99 diagnostic. If the fix is a circulator pump, a valve or an expansion tank, you get that price in writing before we start, and you decide.
Want a closer number before anyone comes out? The boiler estimator asks a few questions about yours and shows the range for that job.
What’s different in Oakton
Across ZIP 22124’s 5,922 owner homes, gas heats about half and electricity a little over four in ten, mostly with furnaces and heat pumps. Nearly half the homes went up between 1980 and 1999 around ducts, so a hot water boiler in Oakton usually sits in the close to four in ten built before 1980, where radiators and baseboard are. Fewer than one in twenty owner homes predates 1960, so the boilers here are mostly in the 1960s and 70s houses rather than older ones.
Townhouses are about one in five Oakton owner homes and condos about one in seven; in either, a boiler tends to sit in a closet next to the water heater. A wall-hung combi can take both jobs and vent through the wall, at $12,782 to $16,500 installed, which gives that room back.
In the detached houses, about six in ten owner homes, the choice usually turns on the chimney. If it’s sound, a cast iron boiler can go back on it; if it isn’t, a condensing boiler venting through the side of the house leaves the chimney out of the job. Either way, the County’s permit and chimney vent rules apply to every Oakton address. In a detached house the boiler usually has a basement or a utility room with space to work, so the job is the boiler and its venting, not the room.
Only about one in eight homes here is rented, so most Oakton boiler owners decide for themselves between repair and replacement, and the $99 diagnostic is the place to start: a pump, a valve or an expansion tank is a repair, a leaking heat exchanger is not. If an Oakton boiler fails in a cold snap, the replacement can start first, with the County’s permit application in by the end of the next working day, and Fairfax County Fire and Rescue’s fall advice, gas appliances inspected and a CO alarm on every floor, applies to a boiler as much as a furnace.
Neighborhood by neighborhood
Census figures for the owner-occupied homes in each place, and what a boiler call there usually meets.
| Place | Median home built | Most homes are | Heated with | What a boiler call usually meets |
|---|---|---|---|---|
| Oakton | 1981 | single-family houses, about 4 in 10 | gas, about 6 in 10 | 1980s and 90s houses, mostly forced air; boilers in the older ones. |
| Difficult Run | 1982 | single-family houses, nearly all | gas, about 6 in 10 | 1980s and 90s houses, mostly forced air; boilers in the older ones. |
By the numbers
From the Census Bureau’s 2020 to 2024 survey, owner-occupied homes unless it says otherwise.
ZIP 22124 as a whole: every Oakton address. The Oakton Census place in the table also takes in streets with Vienna and Fairfax mail.
What it’s telling you
When both are near the end, replacing them with one combi can be cheaper and smaller than two new appliances. Ask for the combi price beside the like-for-like one. It also opens up floor space that closet never had.
Close view of a SwiftPro boiler installation in Northern Virginia showing the expansion tank, automatic air vent, fill valve and the vent connector into the chimney.
Safety and paperwork
Fairfax County requires a permit to replace any gas appliance, even like for like: a gas water heater, furnace or boiler. Replacing a fuel-burning appliance also needs a chimney vent certification. Source.
Fairfax County lists replacing a heating or cooling system as mechanical permit work. Source.
Fairfax County Fire and Rescue names a faulty gas furnace or water heater as a carbon monoxide source, says to have gas appliances inspected every fall, and to put a CO alarm on every floor. Source.
Fairfax County Fire and Rescue says to have the heating system cleaned and checked by a professional every year, and to keep anything that burns at least three feet from the furnace and the water heater. Source.
Our Virginia Class A contractor license, 2705192276, is on the side of the van.
Choosing who works on it
Questions to ask anybody who quotes you, us included.
In a townhouse closet, the combi often wins on space. Ask for both numbers in writing so you can compare.
A hot water boiler is half heating system (the burner, gas valve, flue and controls) and half plumbing (the water loop, circulator pumps, expansion tank, relief valve and zone valves). We hold a Virginia Class A license and run separate heating and plumbing teams, so each half gets a tech who does that trade every day.
A new boiler can stay on the chimney or vent out the wall in plastic pipe. A good quote says which, and whether the chimney needs a liner, because that’s where two quotes for the same boiler usually split.
Two of our crew going over a work order before the day's calls.
From our Google reviews
5.0 stars across 1,132 reviews. Read them on our reviews page.
…I had the pleasure of working with Efrain and Alex last year on a Boiler heater. The quality of work and total professionalism contributed 100% to my decision…
Where we work
Next door to Oakton: Fairfax, Vienna, Reston, Dunn Loring and Herndon.
Questions
Some do, usually in a shared closet with the water heater. A combi that replaces both is often the right fit there. Mention the closet’s size when you book so the right boiler comes to the quote.
Swapping the boiler does, repairing it doesn’t. Fairfax County treats any gas appliance replacement as permit work and wants the chimney vent certified too.
No. We work on hot water boilers, the kind that heat radiators or baseboard, on natural gas or propane. If yours is steam or burns oil, we’ll tell you on the phone, and a switch to a heat pump or a gas or propane boiler is ours to price.
Ready when you are
Call any time: we run 24/7 emergency service. Or send the form at the top. A tune-up is $99, a repair starts with the $99 diagnostic, and a new boiler gets a written price before any work.
SwiftPro Heating, Cooling & Plumbing
4230 Lafayette Center Dr N, Chantilly, VA 20151
44679 Endicott Dr, Suite 211, Ashburn, VA 20147
Virginia Class A contractor license #2705192276
SwiftPro Heating, Cooling & Plumbing is a licensed, BBB Accredited (A rating), independently owned heating, cooling and plumbing company in Chantilly, serving Oakton and the rest of Northern Virginia. Virginia contractor license #2705192276. 5.0 stars across 1,132 reviews on Google, Angi, Yelp, the BBB and Facebook. SwiftPro maintains a dedicated HVAC team and a dedicated plumbing team.
From SwiftPro Heating, Cooling & Plumbing in Chantilly. Housing figures are the Census Bureau’s American Community Survey, 2020 to 2024, for each place named; permit, water and sewer facts link to each office’s own page and were checked in September and October 2026.