Water heater flush in Alexandria.
Water heater flushes and tankless descaling in the City of Alexandria and on the Fairfax County side. $99 for a tank flush right now.
- Tank or tankless, any brand
- Priced before we start
- Pay after the visit
Book a flush or a descale
Two water companies in Alexandria, and both run hard.
Alexandria gets its water two ways. Inside the City it comes from Virginia American Water, which buys it already treated from Fairfax Water, and the company’s 2025 report puts hardness at 78 to 191 milligrams per liter, 4.6 to 11.2 grains per gallon. On the Fairfax County side, from Hybla Valley out to Kingstowne, Fairfax Water delivers it directly; its 2025 plant figures ran from 3.0 up to 10.8. Either way it’s past the 4 grain mark where Navien wants a tankless descaled every year when there’s no softener.
Every spring the hydrants get flushed, and Virginia American Water says that’s when Fairfax Water changes its disinfectant for a few weeks. If the tap runs discolored, its advice is to run the cold until it clears. Whatever gets stirred up in the mains can settle in a tank, one more reason the bottom of an Alexandria water heater is worth draining once a year.
Where the heater sits changes from street to street. More than half the homes in the City are in condo and apartment buildings, where the heater usually lives in a closet over a drain pan with no floor drain nearby, so the flush runs into a bucket or the laundry standpipe. Kingstowne and Franconia are about half townhouses. Fort Hunt is nearly all single-family houses, its median home built in 1963, and Mount Vernon is three quarters single-family, with the heater in the basement by a floor drain, usually the second or third one the house has had.
Close to six in ten occupied homes in the City are rented. Between tenants is the easy time: the closet’s clear, nobody needs a shower, and the owner learns how old the tank really is before it turns into the next tenant’s first phone call.
Where the water heaters are across Alexandria.
Census figures for the owner-occupied homes in each place, and what we’d look at first on a flush there.
| Place | Median home built | Most homes are | Heated with | What we’d look at first |
|---|---|---|---|---|
| City of Alexandria | 1970 | condo and apartment buildings, about 5 in 10 | gas, about 6 in 10 | Closet heaters over a pan: we flush to a bucket or the laundry drain. |
| Rose Hill | 1969 | single-family houses, about 7 in 10 | gas, about 7 in 10 | Older houses on their second or third heater: we read the label first. |
| Franconia | 1986 | townhouses, about 5 in 10 | electricity, about 6 in 10 | Townhouses: utility rooms and closets, so we check the pan and the valves. |
| Fort Hunt | 1963 | single-family houses, nearly all | gas, about 8 in 10 | Older houses on their second or third heater: we read the label first. |
| Kingstowne | 1994 | townhouses, about 5 in 10 | gas, about 7 in 10 | Townhouses: utility rooms and closets, so we check the pan and the valves. |
| Woodlawn | 1976 | townhouses, about 4 in 10 | electricity, about 6 in 10 | Older houses on their second or third heater: we read the label first. |
| Lincolnia | 1982 | single-family houses, about 4 in 10 | gas, about 7 in 10 | A yearly flush, and a look at the anode rod. |
| Mount Vernon | 1967 | single-family houses, about 7 in 10 | gas, about 7 in 10 | Older houses on their second or third heater: we read the label first. |
Alexandria houses, by the numbers
From the Census Bureau’s 2020 to 2024 survey, owner-occupied homes unless it says otherwise.
The City of Alexandria
- Median home built1970 Census
- Built before 1980about 6 in 10 Census
- Built since 2000about 2 in 10 Census
- Most homes arecondo and apartment buildings, about 5 in 10 Census
- Heated withgas, about 6 in 10 Census
- Rentedabout 6 in 10 Census
- In the City of Alexandria, about 6 in 10 homes were built before 1980, so the water heater has been replaced at least once. The label says how old this one is, and we’ll tell you what that means.
- In the City of Alexandria, about 5 in 10 homes are in condo and apartment buildings. Those heaters usually sit in a closet over a drain pan, so we flush into a bucket or a laundry drain.
The Fairfax County side
- Built before 1980about 5 in 10 Census
- Built since 2000about 1 in 10 Census
- Most homes aresingle-family houses, about 4 in 10 Census
- Heated withgas, about 6 in 10 Census
- Rentedabout 3 in 10 Census
- On the Fairfax County side, about 6 in 10 owner homes heat with gas. If the water heater is gas too, the flush includes a look at the burner and the vent.
What a water heater flush costs in Alexandria.
Same prices as our water heater flush page, anywhere in Northern Virginia, and you pay after the visit.
- Tank water heater flush, with the plumbing check$99
- A tank flush on its own, normally$199
- Tankless descale, with the plumbing check$300
- A tankless descale, regularly$350
Both visits include a whole-home plumbing check: supply lines, shutoffs, a pressure reading, drains, toilets and traps.
One per household, owner-occupied homes, limited time. A leaking tank, or one that’s 15 years old, needs repair or replacement, not a flush.
Why people in Alexandria book a flush.
It lives in a condo closet
We flush it into a bucket or the laundry drain, not across the floor, and check the pan under it while we’re there.
It pops or rumbles
That’s water boiling under a layer of sediment on the bottom of the tank. A flush clears it out.
Nobody knows when it was last done
Which is most houses. The drain valve at the bottom of the tank has usually never been opened.
How to pick who flushes your water heater in Alexandria.
Questions worth asking anybody you call, us included.
In an Alexandria condo, whose water heater is it?
Usually the unit owner’s. The heater in your closet serves your unit, while the pipes shared through the building belong to the association. A flush only touches your heater and the drain it empties into.
Do they check the anode rod and test the relief valve?
The anode is the part that corrodes so the tank doesn’t, and the relief valve is the tank’s safety valve. A flush that skips both is just draining water.
On a tankless, do they pump descaler through it?
A real descale isolates the heater at its service valves and pumps solution through the heat exchanger, then rinses it and cleans the inlet screen.
What our customers say.
Hard to find service like this in Alexandria.
I am very happy with the service I received in installing my water heater. Tyson and the crew were very kind and cleaned everything up before they left. I would really recommend this company.
Had the water heater replaced and a quote for my HVAC. Both technicians were friendly and helpful. Prices were decent. Would use again.
5.0 stars across 884 Google reviews. Read them on our reviews page.
Water heater flush questions from Alexandria.
Is Alexandria’s water hard?
Moderately hard to hard on both sides of the city line: 4.6 to 11.2 grains per gallon in the City and 3.0 to 10.8 on Fairfax Water’s county side, going by each utility’s 2025 figures. That calls for a yearly tank flush, and a yearly descale on a tankless.
How much does a water heater flush cost in Alexandria?
$99 right now for a tank, with a whole-home plumbing check. The flush on its own is normally $199. A tankless descale is $300 right now, regularly $350.
Water heater flushes in the towns next door.
More from SwiftPro in Alexandria
Book the flush, tank or tankless.
Call, or book online and pick a window. Tell us tank or tankless, and the tech brings the right gear.
SwiftPro Heating, Cooling & Plumbing is a licensed, BBB Accredited (A rating), independently owned heating, cooling and plumbing company in Chantilly, serving Alexandria 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.