I've recently had a mains pressure unvented hot water system fitted and I am
absolutely delighted with it (fantastic shower pressure without any noisy
pumps).

My question relates to the pressure vessel for the central heating system.
The vessel has a pressure gauge and a water feed attached and my plumber
recommended that I have it set at 1 bar pressure. When the system is idle
the pressure is currently 1 bar and when it's in demand it's nearly 2 bar.

Is this correct or should I have it running at 1 bar ? I don't want to run
it at too high a pressure and risk the rather aged pipework springing a
leak.

KW