A phenomenon known as Water Hammer.
Basically resonance in the pipes. Something is vibrating under the pressure of water going into your cistern.
Usually renewing the ball valve washer sorts the problem out.
After that its a case of securing any loose pipes and reducing the pressure of water going to the cistern.
When you turn on another tap reduction of pressure is exactly what's happening and that's why it often stops the resonance
Slugbabydotcom
November 2007
howtomendit.com for free repair help, information and advice.
