Pilot Operated Valve

Description

Pilot Operated Valve (Walich, Ductile Iron, PN16)

The pilot operated valve is an automatic hydraulic control valve used to regulate pressure, flow, and level in water supply and water tank systems. Instead of relying on manual operation, a small pilot circuit continuously senses the line condition and hydraulically drives the main valve open or closed — giving smooth, accurate, self-adjusting control with no external power required. Supplied by Sabelita in Singapore with a ductile iron body rated to PN16, it is built for municipal water, building services, pump stations, and tank management duties.

How it works

A pilot operated valve pairs a large diaphragm-actuated main valve with a small pilot valve. The pilot senses the control parameter — downstream pressure, upstream pressure, tank level, or flow — and adjusts the water pressure in the main valve’s control chamber. That pressure difference is what opens, closes, or throttles the main valve. Because the line pressure itself does the work, the valve reacts automatically to changing demand and holds a stable setpoint without an operator or electricity.

Available configurations

The pilot operated valve platform can be configured for several control duties. Trim this list to the variants you actually stock:

Pressure reducing valve (PRV) — holds a constant, lower downstream pressure regardless of inlet fluctuation.
Differential float / level control valve — opens and closes to keep a water tank or reservoir at a set level.
Silent (non-slam) check valve — prevents reverse flow and closes smoothly to avoid water hammer.
Pressure sustaining / relief valve — maintains minimum upstream pressure or relieves excess pressure.
Flow control valve — limits flow to a preset maximum.

Applications

Building and high-rise water supply, water tank inlet control, pump station protection, pressure management across zones, irrigation and process water, and fire/utility water networks.

Why buy from Sabelita

As a Singapore-based water supply and plumbing specialist, we stock pilot operated valves alongside the pumps, water tank accessories, pipe fittings, and valves that go with them — so you can source a complete tank or pressure-management setup from one supplier, with local advice and support.

FAQs

What is a pilot operated valve?

A pilot operated valve is an automatic control valve in which a small pilot valve senses a line condition (pressure, level, or flow) and uses the system’s own water pressure to open or close a larger main valve. It regulates the system automatically without manual operation or external power.

How does a pilot operated valve work?

The pilot circuit controls the pressure inside the main valve’s diaphragm chamber. When it bleeds pressure off, the main valve opens; when it builds pressure up, the main valve closes. This lets the valve continuously self-adjust to hold a set pressure, level, or flow.

What is the difference between a pilot operated valve and a direct-acting valve?

A direct-acting valve reacts to line pressure directly against a spring or diaphragm, which is simple but less precise and better suited to small sizes. A pilot operated valve uses a separate pilot to control the main valve, giving more accurate, stable control across larger sizes and wider flow ranges.

What configurations are available?

Common duties include pressure reducing, level/float control, non-slam check (reverse-flow prevention), pressure sustaining/relief, and flow control — the same main valve is configured with a different pilot for each function.

What does PN16 mean?

PN16 is a pressure rating indicating the valve is designed for a nominal working pressure of 16 bar. It suits most building and municipal water applications.

Where are pilot operated valves used?

In building and high-rise water supply, water tank inlet and level control, pump station protection, zone pressure management, irrigation, and utility water networks.