What is the purpose of a check valve in plumbing systems?

The purpose of a check valve in plumbing systems is to prevent backflow. This device allows fluid to flow in only one direction, ensuring that water or other substances do not flow backward through the system. Backflow can lead to contamination of potable water supplies and can disrupt the normal operation of plumbing systems. By installing a check valve, the risk of backflow is mitigated, thereby protecting the integrity of water supply and preventing potential health hazards associated with contamination.

Other functions, such as controlling water temperature, filtering contaminants, or reducing pressure, do not fall within the scope of the check valve's design. Instead, these tasks are typically managed by other types of plumbing devices specifically designed for those functions.