What is the purpose of a pressure relief valve in plumbing systems?

The purpose of a pressure relief valve in plumbing systems is crucial for maintaining safety, particularly in water heating applications. When pressure builds up in a water heater due to heating the contents, the pressure relief valve serves as a safety mechanism to release excess pressure that could otherwise lead to system failure or an explosion.

This valve automatically opens when the pressure exceeds a preset limit, allowing water to escape and reducing the internal pressure levels to safe limits. This operation is essential for preventing damage to the tank and other components of the plumbing system.

While controlling water flow, regulating temperature, or filtering impurities are important functions in plumbing systems, none of these roles pertain to the fundamental function of a pressure relief valve, which specifically addresses pressure buildup scenarios.