Noisy pipework

Hi all,
I've recently had some plumbing done which involved replacing the pipe work from the stopcock to the sink (about 10 metres of pipe) and putting in the plumbing for a water softener and dishwasher. Ever since, whenever there is a very slow flow of water through the new pipe work it makes a groaning sound which is driving me potty. At the moment I believe that the most obvious culprit is what I assume is a one-way valve which has been put in before the water softener outlets.
The plumber is coming back to finish some other stuff next week so I'll obviously mention it then but, before that can anyone help me with these questions, please ?
1) Is it likely to be the valve that is vibrating at low flow rates ? 2) If so, is this normal ? 3) If it is normal does anyone know of a "digital" ballcock for a cold water storage tank (i.e.one that is either fully open or fully shut so there's no low flow rate through the pipes) ?
In case anyone's worried, the DIY bit may be me replacing the valve or the ballcock if I can't wait for the plumber to return :-)
Cheers,
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In uk.d-i-y, John Anderton wrote:

Try adjusting the stopcock.
--
Nigel Mercier

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Try either a Fluidmaster or Torbeck style ballcock - these are pretty much either on or off. Available from B&Q etc or Screwfix.
Alex
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Thanks for the tip,
Cheers,
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.