K
Kmort78
Had a quick look at my mates boiler ,it was on lock out due to low pressure,to cut a long boring story short the expansion vessel is knackerd or under charged,removed case but could not see valve to test or refill ,no manual on site and i have not delt with one of these before, but it looks like you have to strip out most of the controls or take the boiler of the wall to get to the vessel