Why Does My Check Valve Flutter?

[Dom]

So I've heard the arguments both for and against using a check valve on the return line. I've read the solutions to install as an alternative to check valves.

I've chosen to use a check valve.

When I turn off the return to test, the valve doesn't close completely... it just "flutters". Why??

 

[RocketEngineer]

Because there is likely something on the sealing surface. A snail, a worm, a piece of grit. Anything can grow/crawl into the valve and cause it to fail. That’s why they are not worth including.

 

[Carwin]

Wow, I have always used a check valve and never had a problem.

 

[RocketEngineer]

It may not but our tanks are biologically active on any surface that contacts water. It doesn’t take much to screw up a check valve.