if the pressure exceeds 3bar then a pressure relief valve opens to discharge the excess,once the excess is discharged the valve should close and the water stop coming out.Sometimes the valve doesnt close properly and you have to top up the boiler frequently.If the water stop valve on the filling loop doesnt close fully and you leave the braided hose connected then the boiler will continually fill and the pressure will rise and start to discharge at 3bar.So check the pressure gauge/display to determine whats happening.
combiking, March 2008
