AC repair in Fairfax.
AC and heat pump repair in the City of Fairfax and the county side, priced from a published book before any work starts.
- Prices in writing, first
- Common parts on the truck
- Dedicated HVAC team
Get your AC repair priced
Most Fairfax houses cool with an AC beside a gas furnace.
In the City of Fairfax and Mantua, most houses heat with gas, so the cooling is a straight air conditioner outside and a furnace inside, and the two share one blower. When that blower wheel is caked in dust, both seasons suffer, and cleaning it is one of the cheaper fixes on the list.
Fair Lakes and Fair Oaks are younger, mostly 1990s, so most of those houses are on their second system by now. Kings Park West has the most electric heat of any place with a Fairfax address, which usually means heat pumps: outdoor units that work all year.
Repairs go ahead without paperwork. Replacing the system is permit work, and a Fairfax address can mean either office: the City of Fairfax inside the city line, Fairfax County everywhere else. The County also asks for an A2L certification with any new heat pump or air conditioner on the newer refrigerants.
Maintenance-plan AC tune-ups are a bigger share of the work in Fairfax than in any of the other towns where we work most. That’s the visit where a weak capacitor or a matted outdoor coil gets caught in the spring, before a July afternoon finds it for you.
What’s cooling the houses across Fairfax.
Census figures for the owner-occupied homes in each place, and what that usually means for the air conditioning.
| Place | Median home built | Most homes are | Heated with | What the cooling usually is |
|---|---|---|---|---|
| Fair Oaks | 1995 | condo and apartment buildings, about 5 in 10 | gas, about 6 in 10 | Condo and apartment buildings: small splits and fan coils, roof or balcony condensers. |
| City of Fairfax | 1966 | single-family houses, about 5 in 10 | gas, about 7 in 10 | Older houses on their third or fourth system, usually a gas furnace with a separate AC. |
| Kings Park West | 1976 | single-family houses, about 7 in 10 | gas, about 5 in 10 | Older houses on their third or fourth system, usually a gas furnace with a separate AC. |
| Merrifield | 1990 | condo and apartment buildings, about 6 in 10 | gas, about 6 in 10 | Condo and apartment buildings: small splits and fan coils, roof or balcony condensers. |
| Fair Lakes | 1998 | townhouses, about 3 in 10 | gas, about 7 in 10 | 1980s and 90s houses, most on their second or third system. |
| Mantua | 1968 | single-family houses, about 7 in 10 | gas, about 7 in 10 | Older houses on their third or fourth system, usually a gas furnace with a separate AC. |
Fairfax houses, by the numbers
From the Census Bureau’s 2020 to 2024 survey, owner-occupied homes unless it says otherwise.
The City of Fairfax
- Median home built1966 Census
- Built before 1980about 7 in 10 Census
- Built since 2000about 2 in 10 Census
- Most homes aresingle-family houses, about 5 in 10 Census
- Heated withgas, about 7 in 10 Census
- Rentedabout 3 in 10 Census
- Gas heat means a furnace inside and a separate air conditioner outside, sharing one blower, so a tired blower shows up in both seasons.
- Older houses often have returns too small for today’s systems, and a starved return is one of the ways an AC freezes up.
The Fairfax County side
- Built before 1980about 3 in 10 Census
- Built since 2000about 4 in 10 Census
- Most homes arecondo and apartment buildings, about 4 in 10 Census
- Heated withgas, about 6 in 10 Census
- Rentedabout 5 in 10 Census
- Condo cooling is often a small split or a fan coil, and the building may control the roof and the refrigerant lines.
What AC repair costs in Fairfax.
The same price book as our AC repair page. The diagnostic visit is about $99, and the common parts ride on the truck, so most of these get fixed on the first visit.
- Run capacitor replaced$240 to $370
- Contactor replaced$290 to $425
- Condensate drain cleared$175 to $420
- Refrigerant topped up$190 to $740
- Blower wheel pulled and cleaned$300 to $440
- Refrigerant leak found and repaired$1,850 to $2,700
- Repair diagnostic visitabout $99
Often same-day, and we will tell you honestly when we can get there.
With Comfort+ membership, any service is 15% off, and the cooling and heating maintenance visits are part of the membership.
What a failing AC in Fairfax usually does.
A leak on a pre-2010 system
Plenty of Fair Lakes and Fair Oaks houses got their second air conditioner in the 2000s. If the label says R-22, that refrigerant stopped being made in 2020, so a leak on that unit is the moment to price the repair and the replacement side by side.
The air coming out is warm
Usually the outdoor unit has stopped running. A hum with no fan turning is almost always the run capacitor; silence while the thermostat calls is usually the contactor.
It runs all day and never cools
That’s an airflow problem far more often than a refrigerant problem: a clogged filter, a matted coil, or a blower wheel packed with dust.
How to pick the best AC repair company in Fairfax.
Questions worth asking anybody who comes out, us included.
Do they know which permit office you’re under?
A Fairfax mailing address can be the City or the County. It doesn’t matter for a repair, but for a replacement it decides who inspects, and a contractor should know which before quoting.
Do they publish prices?
A company that prints what a capacitor or a contactor costs has already told you the number. One that won’t say until the tech is in your driveway hasn’t.
Do they measure before they sell refrigerant?
A healthy system drops the air somewhere around 16 to 22 degrees across the indoor coil. Low refrigerant means a leak, and topping it up every summer is the expensive way to find that out.
Will they tell you when it’s the end of the road?
Some repairs aren’t worth doing on a 20-year-old system. The good answer shows you the repair price and the replacement price side by side and lets you pick.
What our customers say.
I would gladly recommend them to anyone in the greater Fairfax/Alexandria area without reservation.
Swiftpro came out the same day I called when my AC was out and had it fixed in less than an hour after arriving.
Aaron and Marshal did a great job. There were professional and respectful. Aaron had AC units more efficient and maintenance free.
5.0 stars across 884 Google reviews. Read them on our reviews page.
AC repair questions from Fairfax.
Does an AC repair in Fairfax need a permit?
No, a repair doesn’t. A new system does, and who issues it depends on the side of the city line: the City of Fairfax has its own permit office, and outside the line Fairfax County treats a heating or cooling replacement as mechanical permit work.
Why is my Fairfax house hotter upstairs than down?
Usually not a failing AC. One system cools two floors, heat rises, and the top floor sits at the end of the longest duct runs. Balancing the dampers, zoning, or a ductless head upstairs fixes it; a bigger unit doesn’t.
My Kings Park West heat pump blows cool air in winter. Is it broken?
Not necessarily. Heat pump air feels cooler than furnace air, and every so often the system runs a defrost cycle that blows cool for a few minutes. If it’s cool all the time, or the outdoor unit is buried in ice, that’s a call.
How much does AC repair cost in Fairfax?
The diagnostic visit is about $99. The common repairs: a run capacitor $240 to $370, a contactor $290 to $425, a condensate drain cleared $175 to $420, refrigerant topped up $190 to $740. A refrigerant leak repair runs $1,850 to $2,700.
Should I repair it or replace it?
Fix the cheap parts on almost anything. Think twice about a big repair on a system over 15 years old, and about any leak on an R-22 system. The HVAC estimator prices a new system in about a minute, so you can put the two numbers side by side.
AC repair in the towns next door.
- AC repair in Oakton
- AC repair in Burke
- AC repair in Vienna
- AC repair in Annandale
- AC repair in Springfield
More from SwiftPro in Fairfax
Tell us what your AC is doing.
Call, or book online and pick a window. The tech prices the repair from the book before starting, and if it’s the end of the road 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 Fairfax 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.