I live in a flat with a worcester greenstar condensing boiler, it has been leaking from the flue pipe since I moved in, (the flat is only 4 years old as is the boiler) british gas have been round several times to deal with it and all they did was insulate the flue pipe (as recommended by worcester) through the flt above & in the roof space, I am desperate to stop this happening & is causing much stress, please help me someone I do not know what to do!!!!