Why household water pressure runs high here
Water pressure at your tap is a function of where your house sits relative to the system that feeds it — the elevation of the storage and the pressure zone you are in. Utilities have to deliver enough pressure for the highest and furthest homes on a zone, which means homes lower down can see considerably more pressure than they need.
Fairfax Water describes this directly in the context of its Second-High Pressure Zone Expansion Project: pressure zone changes meant some customers in the affected area would see water pressure at or above 80 PSI, and it identified and wrote to those households about the possible need for a PRV.
Pressure above about 80 PSI is not a plumbing curiosity. It is what shortens the life of supply lines, fill valves, washing-machine hoses, water heaters and every seal in the house, and it makes an ordinary failure more damaging when it happens.
What a PRV is, and where to find yours
Fairfax Water’s own definition is short: a PRV is a device that reduces the water pressure entering a residence, resulting in water pressure that is less than 80 PSI. On where it lives, the utility says a PRV is typically installed where the water line enters your home — most likely in the basement, though it may be elsewhere — and advises contacting a plumber if you are unsure whether your home has one or needs one.
Signs a pressure reducing valve is failing
PRVs are mechanical and they wear out. The symptoms are easy to miss individually and fairly obvious together:
- Pressure that has crept up over months — taps that hit harder than they used to, showers that feel aggressive
- Pressure that fluctuates, or that is noticeably different at different times of day
- Banging or hammering in the pipes when a valve or appliance shuts off
- Toilet fill valves and faucet cartridges failing more often than they should
- A relief valve on the water heater discharging periodically
- Pressure that has dropped instead — a failed PRV can stick closed as well as open
The way to settle it is to measure rather than guess. A gauge on an outside spigot or laundry connection reads static pressure directly, and a reading well above 80 PSI is the number that matters.
Does Fairfax Water replace the PRV?
No — and this is the question that sends most people down the wrong path first. Fairfax Water’s Meter Shop FAQ answers it in as many words: asked about a plumber saying a new PRV is needed and can be obtained from Fairfax Water, the utility responds that Fairfax Water does not maintain or replace PRVs, and that you will need to contact a licensed plumber to have it replaced.
The same page draws the boundary for the meter itself. Fairfax Water maintains the actual meter portion; pipes, the copperhorn setting, main line valves and similar components are the customer’s responsibility, requiring a licensed plumber for repairs. If you suspect a leak on an inside meter, the utility asks you to email photographs to the Meter Shop before anything else.
Who owns the valve, and when to call a plumber
The PRV sits on your side of the meter, on your plumbing, and it is yours. Fairfax Water is explicit that the decision to install one is ultimately the homeowner’s, and that it assumes no responsibility for damages due to a change in water pressure.
On the code question, the utility’s wording is worth reading carefully: county plumbing code requires that PRVs are installed in new construction if the pressure is above 80 PSI. For a home that is not new construction it is not required — though you may choose to install one to meet the new-construction standard. So an older house with high pressure is not in violation of anything; it is simply carrying a risk its owner can choose to remove.
If a PRV is installed, Fairfax Water notes it must conform to ASSE 1003 or CSA B356 as per Virginia Plumbing Code, with those certifications listed on the tag attached to the valve — and that residents must use a plumber who is insured and licensed in the Commonwealth of Virginia.
About the reimbursement programme
Fairfax Water did run a reimbursement programme, but it was narrow and it has closed. It applied only to homes it had specifically identified as facing future pressure above 80 PSI because of the Second-High Pressure Zone Expansion, those households received letters, and the programme did not cover replacing an existing PRV. The stated deadlines — installation by 1 February 2021 and reimbursement requests by 31 March 2021 — have long passed. If anyone tells you Fairfax Water will pay for your PRV replacement today, check the current programme page before believing it.
What to do next
Measure the pressure first. If it is comfortably below 80 PSI and stable, you have answered the question. If it is high, or it swings, or you have the fixture-failure pattern above, the next step is a licensed plumber looking at whether you have a PRV, whether it is still regulating, and whether the rest of the system has been taking a beating in the meantime. That last part matters: a house that has run at high pressure for years often has more than one tired component.
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Sources
- Fairfax Water — PRV information — Fairfax Water
- Fairfax Water — Meter Shop — Fairfax Water