Wye check valve noise

[ChuckT]

So I have a pair of 3/4inch wye check valves installed on my return lines. And while fluid testing my new tank I noticed that I get some chatter from them if I have my pump (varios 6) set to 3 or above. It's not consistent, just sometimes. On setting 4 it's only very intermittent ( very faint noise, and very brief) level 3 is more frequent. Is this normal?
Thanks

 

[TexanCanuck]

That depends on if it a swing-check or piston-check design, and how it is installed (vertical vs. horizontal)

Do you know the make and model of the valve? Can you provide a picture of it's installation?

The noise you are hearing is likely Flow-induced vibration of the plug head. Long-term, this will erode the valve seat causing it to leak.

Having said all of that, I wouldn't worry too much unless the noise is bothersome. The reality is that these aquarium-grade check valves are not really designed to be truly leak-tight and will slowly allow water to leak past them when you shut your return pumps off ... they just do it slowly enough that it doesn't create a problem over the 5 to 10 min feeding cycle.

 

[ChuckT]

I got the Georg Fischer wye check valve from BRS. And it's installed vertically

 

[TexanCanuck]

OK .. that is a piston-check design.

When installed vertically, is the piston (the "Y" part) pointed UPWARD and is the flow entering the valve from the BOTTOM?

 

[ChuckT]

Yup, that's exactly how is installed... Funny thing is that on 3 the right side chatters and left doesn't. On 4 right side is quite and left side will chatter VERY QUIETLY and rarely

 

[TexanCanuck]

That's not so unusual ... even of they are all fed from the same return pump, small differences in piping will mean the flow rates in each line will be different, and as a result so will flow-induced vibrations.

 

[ca1ore]

Wye check valves will do this - it’s the weighted check vibrating in the water flow. Usually increasing pump flow will solve the issue. I’ve a drawer full of those GF wye checks. This is just one of many reasons they’re in a drawer.

 

[ChuckT]

What are some other reasons?

 

[ca1ore]

They chatter (as you have found), water hammer/bang when they close, source of back pressure/flow loss and as stuff builds up on the seating surfaces, they lose the ability to seal properly. Much better, in my estimation, to use a siphon break hole or locate the return close to the surface of the display.