Open 24/7 for emergencies
A new central air conditioner in Great Falls runs $5,942 to $14,450 installed per system, keeping the furnace. Big houses here run two or three.
Price range
$5,942-$14,450
8yrs @ 7.99%
$84/mo
15yrs @ 9.99%
$64/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 1,131 reviews
One of our HVAC technicians moving a new condenser up a driveway, the van behind him.
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
The same price book our estimator runs on, for a central air conditioner on its own, keeping the furnace you have. A single-stage unit on a small house sits near the bottom; a variable-speed one on a big house, near the top.
A central air conditioner alone, keeping your furnace, installed
$5,942 to $14,450
or $99/mo at 0% APR for 60 months
An air conditioner and furnace together, installed
$8,898 to $23,000
or $148/mo at 0% APR for 60 months
A heat pump in the AC’s place, installed
$8,499 to $21,650
or $142/mo at 0% APR for 60 months
Diagnostic visit, if it may be worth fixing
$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
The HVAC replacement cost estimator narrows it to your house. Then a tech measures, and you get the installed price in writing before anything is ordered.
With Comfort+ membership at $199 a year, the diagnostic visit is included, and half of each repair bill is banked toward replacing that system, up to $1,500.
What’s different in Great Falls
Fairfax County’s dwelling records list central air on 5,822 of the 5,906 houses in 22066, and the middle one has about 3,700 square feet above ground before the basement counts. A house that size splits its cooling: one system for the basement and main floor, another for the bedrooms, sometimes a third for an addition. Each has its own condenser, its own coil and its own birthday. So the price here is per system, and the honest answer is often to replace the one that quit and put a date on the next.
An AC on its own is the job where a furnace sits under the coil. A little under half the owner homes here burn natural gas and about one in twelve burn propane from a tank in the yard; either way the furnace stays and only the cooling side changes. About four in ten heat with electricity, usually through a heat pump, which gets replaced as a heat pump at $8,499 to $21,650 installed. About one in eighteen heat with oil. We don’t work on oil burners, so an oil house is a switch, priced as a heat pump system.
The typical owner’s house here dates from 1986, so the air conditioner out back now is often its second or third. If that one went in during the 2000s, it’s around twenty and most likely holds R-22, out of production since 2020, so every recharge draws down a shrinking supply. The houses built in the 2000s themselves, about one in nine here, may still cool with the builder’s units. Federal energy planners figure a central AC in Virginia lasts about 18 years, and a lot of Great Falls condensers have already outlived that.
The bedroom system is the tricky swap. By the county’s records 75 percent of houses here are two stories, and that system’s coil usually sits in the attic on an air handler or furnace. The new coil comes up through the hatch or the pull-down stair, rides over a pan with a float switch that shuts the cooling off if the drain backs up, and needs its drain routed away from the ceiling below. Downstairs, with a rec room in 83 percent of basements, the coil on the basement furnace often drains through a small pump. Ask to see both on the written quote.
By the numbers
From the Census Bureau’s 2020 to 2024 survey, owner-occupied homes unless it says otherwise.
When it’s time
When the upstairs system can’t hold its setting on a hot day while the basement one keeps up, the attic unit is the one wearing out. It carries the hottest rooms in the house, and in a 1980s house it’s often the older R-22 unit of the pair. A $99 diagnostic tells you whether it’s a part or the end of that system.
An air conditioner put in before 2010 most likely holds R-22, which hasn’t been made since 2020. A leak on one of those usually ends the repair road.
It’s the pump at the heart of the outdoor unit and its costliest part. Out of warranty on an older unit, the repair can come close to half the price of a new AC, the point where Goodman says replacing may be the better money.
Permits, locally
Our Virginia Class A contractor license, 2705192276, is on the side of the van.
Choosing who installs it
Questions to ask anybody who quotes you, us included.
Great Falls has many large and old trees, in the words of the county’s plan for the area, and a condenser under them chokes on leaves and seed fluff. The new one usually goes back on the old pad, where the lines already run. Ask whether open ground a few feet away would serve it better, and price that before install day.
Ask how they picked the size. Copying the old nameplate repeats whatever was guessed when the house was built.
The outdoor unit and the coil on the furnace are rated as a pair. Ask whether the quote replaces both, and what happens to the line set.
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.
Two of our crew going over a work order before the day's calls.
From our Google reviews
5.0 stars across 1,131 reviews. Read them on our reviews page.
On spec and on price for our A/C replacement. Showed up on time and all went as promised
Questions
Not automatically. If one has quit and the other still cools well, replace the first and have the second looked at on the same visit, so you know where it stands before it’s urgent. Each system is priced on its own, $5,942 to $14,450 installed, and a tech reads both labels and measures the rooms each one cools.
The main floor’s. That outdoor unit cools only, sitting on the gas furnace, so it’s an AC-only swap. The bedroom heat pump heats as well as cools, so it gets replaced as a heat pump, $8,499 to $21,650 installed. Some of the bigger houses here mix the two, and the label on each outdoor unit tells you which one you’re looking at.
$5,942 to $14,450 installed for a central air conditioner on its own, keeping the furnace you have; size and efficiency set where yours lands. An AC and furnace together run $8,898 to $23,000. The HVAC replacement cost estimator gives your house its own number.
It’s worth pricing. A heat pump cools exactly like an AC and also heats on mild days, so with your gas furnace it becomes dual fuel. A heat pump system runs $8,499 to $21,650 installed, and we’ll price it both ways.
Ready when you are
Call, or send the form at the top. A tech measures the house and puts the installed price in writing before anything is ordered, and if the old AC is worth fixing, you’ll hear that first.
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 Great Falls and the rest of Northern Virginia. Virginia contractor license #2705192276. 5.0 stars across 1,131 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.