Dear Friend
Well I hope you are a friend because I need some advice, the pressure gauge on my combi boiler just increases above the initial setting.
I have tried to fault find myself but am lost. I bleed the system of air after putting on excess pressure, bleeding every radiator in turn, I usually start downstairs and then go upstairs continually ensuring the pressure is slightly higher than what I require by topping up, but finishing with the pressure at 1.5 bar. When I turn the heating on the pressure rises to about 2.8 bar and then when the system cools down it will have dropped to below 1 bar. I have been through this exercise repeatedly with the same conclusion every time so that now I have to top up every time I want the heating on and then I have to monitor the boiler so that the pressure does not go to high. Sometimes this happens and I have to release pressure or turn the heating off all together.
I am out of work and cannot afford to get anyone in, so I need some guidance, or do I have to wait to afford a specialist. I would appreciate any advice available and any explanation as to why this is happening. The boiler is a Ravenheat RSF 820/20T Fanned combi

Thanks Tommy Myles

Tommy Myles, December 2011

set it cold to 1.1 bar.pressure will rise when hot this is normal.the relief valve will operate if it gets to high so you don't need to worry about it getting to high pressure unless of course it spews hot water out the overflow pipe.if it still fails look for a leak somewhere or the pressure expansion vessel could be faulty

A1, December 2011