i would think the expansion vessel at the back of the boiler has lost its 1bar of air pressure.
steve, January 2009
Hi Tom,
I have a similar problem but cant find any leak and my water meter shows no movement which would indicate a leak ? Did you resolve the problem ?
James
James, January 2009
u have a leak!! check all pipework joints and make sure overpressure valve is not passing. set pressure to 1 bar.
