What to Know First
Compare common valve functions, actuation, supervision and maintenance considerations.
- Identify a valve by its function, not only by shape or colour.
- Record the normal position and how that position is supervised.
- Testing must control discharge, downstream impact and safe restoration.
Common valve jobs
An isolation valve allows a section to be taken out of service. A check valve limits reverse flow. Alarm and wet-alarm valves detect sustained water movement. Deluge valves hold water back until a detection or manual release operates. Pressure-control valves manage excessive or variable pressure.
Agent systems use specialised container valves, selectors and directional valves that must match the system approval.
Normal position must be obvious
A closed isolation valve can disable an entire system. Use locks, seals or supervisory switches as required and show the valve on the system drawing.
A supervisory signal should identify the affected valve or zone clearly enough for staff to respond.
- Tag the valve and protected area
- Show open/closed direction
- Record supervisory switch operation
- Control and document every impairment
Test without creating a new hazard
Before operating a valve, understand where water or agent will go, which alarms will occur and what equipment will start or stop. Inform monitoring centres and affected occupants.
Restore the normal position, confirm pressure and reset every alarm before closing the work order.
Project Checklist
Isolation, alarm, check, deluge, pressure control or agent release.
Size, pressure, material, medium and direction of flow.
Normal position, actuator, release method and supervision.
Trim, drainage, test connection, spares and maintenance access.
Frequently Asked Questions
Can two valves that look the same be substituted?
Not safely from appearance alone. Function, pressure, trim, materials, approval and installation orientation must all match.
Official references
Information is based on reviewed sources and our experience at the date shown. Use it at your own risk and verify current codes, certificates and project conditions. Report an issue or suggest a correction.