Device passport 03
Identify the water pressure regulator before changing the screw
Find the bell-shaped pressure reducing valve, measure pressure, and route high, low, or unstable pressure without guessing from symptoms alone.
A pressure regulator controls downstream pressure; it is not a backflow preventer. The first useful evidence is a gauge reading, the affected fixtures, and the exact model.
Do not make repeated blind adjustments. Very high pressure, active leakage, or a closed-system thermal expansion problem can damage plumbing.
Interactive check
Turn observations into a next step
This narrows the route. It does not replace an on-site test, manufacturer instructions, or local requirements.
Evidence sequence
Move in this order
- 01
Confirm the device
Record the body arrow, make, model, pipe size, and connection type.
- 02
Measure before adjusting
Take static and flowing readings at a reliable hose-thread gauge point.
- 03
Choose adjust, service, or replace
Use the model instructions and the reading pattern rather than a generic turn count.
Identification notes
What to look for
- Usually installed near the water service entry after the main shutoff.
- Often has an arrow on the body and a bell or dome over the spring.
- An adjustment bolt changes the set point only within the model's documented range.
Safe observations
What you can check without taking it apart
- Photograph the label and installation.
- Check multiple fixtures for the same symptom.
- Record static, flowing, and overnight peak pressure.
Stop conditions
Move to qualified help when
- Static pressure remains above 80 PSI
- Water leaks from the body or bell housing
- The main shutoff or isolation plan is uncertain
- Pressure changes accompany water-heater relief discharge
Boundary check
Do not confuse this path with
- A backflow assembly normally has test cocks and separate checks.
- A thermal expansion tank is not a pressure regulator.
- A sewer backwater valve is on drainage piping.
Official local layer
Your utility sets the rule
Manufacturer instructions control adjustment and service. Local plumbing rules and the actual system pressure control the final decision.
Evidence ledger
What this decision path is built on
Manufacturer instructions control adjustment and service. Local plumbing rules and the actual system pressure control the final decision.
- 01Zurn Wilkins · ZURN-PRV-LIBRARYPressure reducing valve product and installation libraryResidential valve families, specifications, repairability, and model-specific instructions. Verified 2026-08-02.
- 02Zurn Wilkins · ZURN-600XL-MANUALModel 600XL installation and maintenance instructionsPressure measurement, adjustment direction, installation, and maintenance cautions. Verified 2026-08-02.
Continue the case
Related next steps
CONTENT REVIEWED · 2026-08-02