Non Return Valves (Check Valves)

A check valve is a valve that normally allows fluid (liquid or gas) to flow through it in only one direction. A check valve can also be called a clack valve, non-return valve or one-way valve. Check valves have an inlet and an outlet, and needs a pressure differential across the valve to crack or open the valve. If there is no pressure differential, the valve will not open and prevents any backflow. There are various types of check valves used in a wide variety of applications.​