On 22/05/2017 17:05, Davey wrote:

Can they keep it at 3.5 bar whatever your usage? If so, then you should
have no problem.


When I had 2 showers going was before our recent building work so there
was a run from street to house of about 25m of 1970's black 1/2"(?)
pipe. When extension went up I re-routed a much shorter direct run to
the other side of the house where the boiler is situated in 25mm (20.5mm
bore), internal copper pipes are now 22mm so I'm hoping this will make a
difference if the main bathroom ever becomes more than the
concrete/block tool shed it's been for the last 5 years.
8¬o