What is the function of a dual check valve in plumbing systems?

The function of a dual check valve in plumbing systems is primarily to provide backflow protection. This device is designed to prevent the reverse flow of water, which can occur when there is a pressure drop in the system or a sudden back pressure. By using two check mechanisms, it ensures that any potential contaminants from the downstream side cannot flow back into the potable water supply.

This is particularly important in applications where the water supply could be contaminated due to various factors, such as connections to irrigation systems, industrial processes, or other non-potable water uses. The dual check valve creates a barrier that helps maintain the integrity of the water supply, safeguarding public health and complying with plumbing codes and regulations surrounding potable water systems.

The other functions often associated with plumbing components, such as standard drainage, flow regulation, and filtration, are not the primary purpose of a dual check valve, which focuses strictly on preventing backflow.