Furnace replacement in Lorton.
A new gas or propane furnace in Lorton runs $4,285 to $14,040 installed, keeping your AC. In Laurel Hill the typical owner’s house dates from 2002.
- Installed price in writing
- Sized to the house, not the old nameplate
- Dedicated HVAC team
Get your furnace priced in writing
Lorton furnaces: builder originals in Laurel Hill, propane out on Mason Neck.
Gas is how most of Lorton keeps warm: about six in ten owners across 22079, and better than eight in ten in Laurel Hill, where the typical owner’s house went up in 2002. A furnace that came with one of those houses has run more than twenty winters, the far end of what most gas furnaces get, and with over four in ten Lorton homes built since 2000, plenty of originals are reaching that age together.
A furnace on its own is the right buy when the air conditioner is the younger half, as it is in plenty of early 2000s Lorton houses. The builders’ outdoor units mostly ran on R-22, which hasn’t been made since 2020, and when one quit, owners often replaced it and its coil and left the furnace alone. The new furnace has to suit that newer cooling side: the right cabinet width under the coil, and a blower that moves the air the coil was sized for.
Where the furnace sits changes the job more than the brand does. In a Laurel Hill single-family house it’s usually in the basement. Two-story houses from those years often add a second furnace in the attic for the bedroom floor, and the new one goes up through the same pull-down ladder opening. In a Lorton townhouse it may be a lowest-level closet with a door barely wider than the cabinet, so we measure the way in before quoting.
Natural gas is the exception on Mason Neck. All of its homes are single-family, the typical owner’s dates from 1973, and only about one owner in ten burns natural gas; about as many burn propane, and close to two in three heat with electricity. A propane furnace is the same replacement as a gas one with the burner set for propane, while the tank and its regulator usually belong to the propane company.
The furnaces across Lorton, place by place.
Census figures for the owner-occupied homes in each place, and what that usually means for the furnace that’s there now.
| Place | Median home built | Most homes are | Heated with | The furnace there now |
|---|---|---|---|---|
| Lorton | 2001 | single-family houses, about 4 in 10 | gas, about 7 in 10 | Builder gas furnaces, many now near twenty years old. |
| Newington | 1981 | townhouses, about 6 in 10 | electricity, about 6 in 10 | Mostly electric heat; gas furnaces are the minority. |
| Laurel Hill | 2002 | single-family houses, about 4 in 10 | gas, about 8 in 10 | Builder gas furnaces, many now near twenty years old. |
| Mason Neck | 1973 | single-family houses, nearly all | electricity, about 6 in 10 | Little natural gas: heat pumps and propane furnaces. |
Lorton houses, by the numbers
From the Census Bureau’s 2020 to 2024 survey, owner-occupied homes unless it says otherwise.
Lorton
ZIP 22079 as a whole: every Lorton address. Most of Newington, in the table, has Springfield mail.
- Median home built1997 Census
- Built before 1980about 2 in 10 Census
- Built since 2000about 4 in 10 Census
- Most homes aresingle-family houses, about 4 in 10 Census
- Heated withgas, about 6 in 10 Census
- Rentedabout 2 in 10 Census
- Townhouse furnaces sit in closets and attics, so the new one has to fit the same space and the same way in.
What a new furnace costs in Lorton.
The same price book our estimator runs on, for a gas furnace on its own, 2 to 5 tons, keeping the air conditioner you have. A single-stage furnace in a small house sits near the bottom; a modulating one in a big house, near the top.
- A gas furnace alone, keeping your air conditioner, installed$4,285 to $14,040
- A furnace and air conditioner together, installed$8,898 to $23,000
- Repair diagnostic visit, if it may be worth fixing$99
The HVAC replacement cost estimator narrows it to your house. Then a tech measures, and you get the installed price in writing, at no charge, before anything is ordered.
Natural gas or propane, in a house, a townhouse or a condo, we replace them all. Oil furnaces we don’t.
When a new furnace makes sense in Lorton.
The AC is ten years old, the furnace twenty-plus
A common Lorton split: the builder’s R-22 outdoor unit got replaced and the furnace kept going. Once that furnace wants a new part every winter, replace it alone and keep the newer cooling side.
It’s still the builder’s furnace
A house from the 2000s often runs the furnace it was built with. Around twenty years, inducer motors and control boards start to go, one after another.
The heat exchanger is cracked
It’s the wall that keeps the burner’s exhaust out of the air the furnace blows through the house. Nobody patches one; a crack ends the repair conversation.
Who signs off on a new furnace in Lorton.
Fairfax County
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.
How to pick the best furnace replacement company in Lorton.
Questions to ask anybody who quotes you, us included.
Did they read the coil’s label before sizing the furnace?
The coil on your furnace was matched to the outdoor unit you’re keeping. Ask whether the new furnace’s blower can move the air that pair needs. A furnace that’s right for the heat but wrong for the coil cools poorly all summer.
Did they size it to your house?
Ask how they picked the size. Copying the old nameplate repeats whatever was guessed when the house was built.
Did they check the air conditioner you’re keeping?
A new furnace has to work with the coil and the outdoor unit already there. Ask whether they looked at both before quoting a furnace on its own.
Will they tell you if it’s worth fixing?
A good company puts the repair price next to the replacement range and lets you choose. Already holding somebody’s big number? Take the free second opinion first.
What our customers say.
Oscar and Ndung were great technicians for our HVAC install! Very knowledgeable and friendly. Would recommend them to others!
5.0 stars across 884 Google reviews. Read them on our reviews page.
Furnace replacement questions from Lorton.
Can I replace just the furnace in my Laurel Hill house?
Yes, if the air conditioner is the younger half. Check the outdoor unit’s label: R-410A or a newer refrigerant means it’s been replaced since the house went up, and a furnace alone at $4,285 to $14,040 makes sense. R-22 means it’s original too, and the pair at $8,898 to $23,000 is the better number.
Do you replace propane furnaces on Mason Neck?
Yes, on River Drive, Gunston Road, High Point Road and anywhere else in 22079. Say it’s propane when you book, and where the tank sits. The HVAC replacement cost estimator gives your range first.
How much does a new furnace cost in Lorton?
$4,285 to $14,040 installed for a gas furnace on its own, keeping the air conditioner you have; size and efficiency set where yours lands. A furnace and air conditioner together run $8,898 to $23,000. The HVAC replacement cost estimator gives your house its own number.
Should I repair it or replace it?
Fix the small parts on almost any furnace. Past fifteen years, with a repair over a third of the price of a new one, replacing usually wins. Not sure which you’re looking at? The diagnostic visit is $99, and the tech prices the repair before starting it.
Furnace replacement in the towns next door.
- Furnace replacement in Fort Belvoir
- Furnace replacement in Springfield
- Furnace replacement in Woodbridge
- Furnace replacement in Fairfax Station
- Furnace replacement in Burke
More from SwiftPro in Lorton
- AC repair in Lorton
- AC tune-up in Lorton
- Air duct cleaning in Lorton
- Dryer vent cleaning in Lorton
- Ductless mini splits in Lorton
- Furnace and AC replacement in Lorton
- Furnace repair in Lorton
- Furnace tune-up in Lorton
- Heat pump replacement in Lorton
- Plumbing in Lorton
- Sewer camera inspection in Lorton
- Sump pump replacement in Lorton
- Water heater flush in Lorton
- Water heaters in Lorton
The range first, then your number.
Call, or book online and pick a window. A tech measures the house and puts the installed price in writing before anything is ordered, and if the old furnace is worth fixing, you’ll hear that first.
SwiftPro Heating, Cooling & Plumbing is a licensed, BBB Accredited (A rating), independently owned heating, cooling and plumbing company in Chantilly, serving Lorton and the rest of Northern Virginia. Virginia contractor license #2705192276. 5.0 stars across 884 Google reviews. SwiftPro maintains a dedicated HVAC team and a dedicated plumbing team.
SwiftPro Heating, Cooling & Plumbing, 4230 Lafayette Center Dr, Suite N, Chantilly, VA 20151, (703) 997-9757. Book online, read our reviews, or see every town we serve.