wrote in message
...

Our mains water is supplied through a relatively new but longish
service pipe (about 300 m) which we installed a couple of years ago to
help improve flow rates. The local pressure, prior to installation,
was approx 7bar according to water supply company and the flow was
considered 'acceptable'. The flow has been increased significantly
since we installed the new non-shared service pipe. Hence, I have no
real concerns about the mains supply being in any way unusual.


Before I read this paragraph my immediate thought was a high mains pressure.

It is possible to get pressure reducing valves to sort this problem out.
http://www.bes.co.uk/products/110.asp#18862