PRESSURE CONTROL VALVES (PILOT OPERATED PRESSURE REDUCING)

A pilot operated pressure reducing valve is considered a pressure control valve within the larger category of Pressure-Regulating Devices as defined by NFPA. This pressure control valve in fire protection systems automatically regulates downstream pressure to protect piping, sprinklers, and equipment from excessive pressure. It uses a small pilot valve that senses downstream pressure and controls the main valve diaphragm. When downstream pressure exceeds the set point, the pilot increases pressure above the diaphragm, causing the main valve to throttle toward closed and reduce outlet pressure. When pressure drops, the pilot releases pressure from the diaphragm, allowing the main valve to open and restore flow. This modulating action ensures stable and consistent pressure delivery, even under variable inlet conditions from fire pumps or municipal mains, supporting reliable sprinkler operation during fire events.