Why is my check valve chattering?

The most common reason a check valve chatters is turbulence.  Very often the turbulence is caused because the check valve is installed too close to the discharge of a pump or is just downstream of an elbow or some other turbulence causing device. Valve manufacturers, including Metraflex, recommend 5-10 straight diameters of pipe directly upstream of the check valves. This allows any turbulence in the system to settle out prior to reaching the check valve. Turbulent flow will cause the disc to be loaded in a random way causing the disc to flutter and bounce.

There are two possible solutions if your check valve is chattering:

1. Move the check valve further downstream from any turbulence causing equipment.

2. Install a Vane Flex, a flex connector with built in straightening vanes, upstream of the check valve.