Hello, my combi boiler is having pressure problems.
Pressure gauge on zero when cold and then when boiler is repressurised gauge rises sharply up into the red section when switched on. Within an hour or so water is being dumped out of the little metal pipe outside and the pressure gauge goes down to a normal level between 1-1.5. Little metal pipe outside has by this time stopped dumping water. Next morning pressure gauge is back on zero.
Does that mean there is a problem with the actual boiler, for instance the expansion vessel rather than a leak on the radiators or central heating pipes? Can't find any wet patches indoors by the radiators.