Check Valve

Check valves are generally installed in pipelines to prevent backflow. A check valve is basically a one-way valve, in which the flow can run freely one way, but if the flow turns, the valve will close to protect the piping, other valves, pumps etc. If the flow turns and no check valve is installed, water hammer can occur. Water hammer often occurs with an extreme force and will easily damage a pipeline or components.

Where are check valves used?

Check valves are used in many different applications. For example, they are often placed on the outlet side of a pump to protect the pump from backflow. Centrifugal pumps, the most common type of water pumps, are not self-priming, and therefore check valves are essential for keeping water in the pipes. Also, check valves are very often used in HVAC systems (Heating, Ventilating and Air Conditioning systems). HVAC systems are e.g. used in large buildings, where a coolant is pumped many stories up. These check valves are installed to make sure that the coolant does not flush back down.