What is the function of a pressure relief valve?

The function of a pressure relief valve is to automatically release pressure from a system when it exceeds a preset limit. This is crucial in maintaining the safety and integrity of pressurized systems, such as those found in steamfitting and pipefitting applications. When the pressure within a system rises above a predetermined level, the pressure relief valve opens to release excess pressure, thus preventing potential damage to the system or accidents that could result from over-pressurization. This mechanism acts as a safety feature to protect equipment and ensure safe operation.

The other options do not align with the primary role of a pressure relief valve; increasing flow rate is related to different components that enhance fluid movement, preventing backflow relates to backflow prevention devices, and filtering out impurities pertains to filtration systems. Each of these functions is specific to other devices within a plumbing system, which highlights the unique and critical role that pressure relief valves play in maintaining safe operating pressures.