In a plumbing system, which component directly works to resolve back-pressure issues?

The double check valve assembly plays a crucial role in addressing back-pressure issues in a plumbing system. Its primary function is to prevent the backflow of contaminated water into the potable water supply. This assembly consists of two independently acting check valves and is designed to allow water to flow in one direction while preventing reverse flow, which can occur due to back-pressure scenarios.

In situations where there is a pressure difference that causes water to flow back into the system, the double check valve assembly's design ensures that the flow is restricted, thus safeguarding the drinking water supply from potential contaminants. This makes it an essential component in any plumbing system that could experience pressure fluctuations, ensuring that the water remains safe and uncontaminated.

While other components also play roles in maintaining system stability, they address different issues. For instance, an atmospheric vacuum breaker is more relevant to preventing back-siphonage rather than back-pressure. A pressure vacuum breaker is similar but primarily protects against the combination of back-siphonage and back-pressure when installed correctly. A water hammer arrestor is designed to alleviate water hammer, which is an entirely different concern related to pressure surges in the system rather than backflow prevention.