Is this water hammer?

[pigoo9]

I've recently replaced the ball valve of the storage tank in the loft as water was flowing out of the overflow pipes. Everything seems to be working fine except that when the tank is just about near full and the flow of water is down to a trickle, the feed-in pipe starts to groan and vibrate quite loudly.

However, when I lift the ball rod up to fully shut the flow of water, the vibration stops. If I let go and let it continue to fill up the vibration returns until the water level is high enough to force the valve to stop flowing.

Also, if i stop the feed via the stop cock and turn it back on again, the vibration is gone.

i'm assuming that this is water hammer from reading other similar posts and invariably the solution is a replacement of the ball valve, but this is a new one.

Any suggestions would be appreciated.

 

[headache5678]

Could you maybe put vaseline inside the mechanism (if you can get to it, that is) and see if that makes any difference ? At least it may help eliminate one possible cause ?

 

[pigoo9]

Could you maybe put vaseline inside the mechanism (if you can get to it, that is) and see if that makes any difference ? At least it may help eliminate one possible cause ?

I could try, what will this do?.. and how much vaseline? surely too much would limit or block the water coming through?

 

[HERTS P&D]

Make sure its coming from the float valve and not loose pipework. Also turn down the stop-cock leading to the float valve

Andy

 

[mysteryman]

Try putting in something to brace or steady the pipe near the ball tap.

 

[45yearsagasman]

That noise is almost surely down to a poor quality ball valve and is vibration of the internal parts.Either take it back and change it or spend a bit more on a better quality valve.

 

[pigoo9]

Thanks for suggestions, I'll give them a try.

 

[headache5678]

I am sure folks here are much more experienced than me but I once had a problem with a ball cock valve on my cistern.

A piston was supposed to move smoothly along a cylinder and block or unblock the hole where water was coming in. However due toi a build up of detrius, the piston got stuck and just a little lubrication helped to make the parts move smoothly.

IMHO, you probably need a new ball valve.