What do check valves prevent?

Check valves are specifically designed to prevent the backflow of water, which means they allow water to flow in only one direction. This is crucial in various water systems to maintain proper water flow and prevent reverse flow that could lead to contamination or other operational issues. For example, in a water distribution system, if the flow direction changes unexpectedly, it could cause potential backpressure or siphoning, which could allow contaminants from lower pressure areas to enter the clean water supply.

While check valves do play a role in ensuring the integrity of a water system, they do not directly prevent air from entering the water supply, block contaminants, or reduce pressure loss in the pipeline, as those are functions associated with other types of equipment and strategies, such as air vents or filtration systems. Thus, the ability of check valves to maintain one-directional flow is central to their purpose and highlights their importance in water treatment and distribution systems.