Which type of valve opens when the inlet pressure exceeds a pre-set pressure?

The Pressure Relief Valve is designed to open when the inlet pressure exceeds a predetermined level, thereby protecting the system from overpressure situations. This type of valve is essential in irrigation systems to prevent damage from excessive pressure, which can lead to burst pipes or equipment failure.

When the pressure in the system rises above the set point of the valve, it opens and allows the excess pressure to escape, usually directing the flow back to a reservoir or through an alternate outlet. This function is crucial for maintaining system integrity and operational safety.

Other types of valves serve different purposes; for example, a Flow Control Valve regulates the flow rate within the system but does not necessarily respond to pressure changes. An Auto Shutoff Valve is designed to close in the event of specific conditions, such as a loss of power or control signal, rather than respond to pressure thresholds. A Check Valve, on the other hand, allows flow in one direction and prevents backflow, without control based on pressure. Each of these valves plays a distinct role in irrigation systems, but the Pressure Relief Valve is unique in its pressure-responsive function.