What it is A Pressure Relief Valve (PRV) is a device designed to control or limit pressure in a system or vessel to prevent process malfunction, instrument or equipment failure, or fire. How it works Pressure is relieved by allowing the pressurized fluid to flow out of the system through an auxiliary channel. The valve is designed to open at a predetermined set pressure to protect pressure vessels and other equipment from pressures that exceed their design limits. When the set pressure is exceeded, the valve opens and directs some of the fluid through the auxiliary passage, providing a path of least resistance for relief. Key benefits Prevents overpressure that can cause damage or safety incidents in systems and vessels. Protects critical equipment such as boilers and solar water heating systems from pressures beyond their design limits. Provides a predictable, pre set response to overpressure, helping maintain system integrity and safety. Simple, reliable method to relieve pressure without requiring active monitoring or intervention. Compatibility and performance Designed for use with systems that require overpressure protection, including boilers and related equipment. Functions by opening at a predetermined set pressure to ensure timely relief and minimize risk of damage to vessels and components. Relies on an auxiliary relief path to divert excess fluid and maintain safe operating conditions. Applications Pressure solar water heaters Gas boilers Electric boilers Heat pump boilers Other equipment or vessels that require a pressure relief valve to avoid excessive internal pressure Use scenarios Scenario 1: A solar water heating system experiences pressure due to intense sunlight or hot water demand; the PRV opens to relieve excess pressure and protect the tank. Scenario 2: A gas boiler experiences a fault that causes pressure rise; the PRV opens at the preset pressure to prevent vessel damage. Scenario 3: An electric or heat pump boiler reaches operating pressure during rapid heating; the PRV relieves pressure to maintain safe system conditions. Notes for selection Choose a PRV that matches the target system's need for overpressure protection, ensuring the set pressure is appropriate for the equipment being protected and the operating conditions.