how do i stop the overflow pipe outside from dripping which is connected some how to the sime combi boiler

appendix, July 2009

replace the expansion vessel

johno, July 2009

from past experience this is caused by one of two things 1. first that the pressure relief valve is sticking open due to lime scale build up .2.the water feed loop that charges the system is leaking into the system and the pressue gauge is rising above 4 bar and letting water out through the valve

ash, July 2009