Have a baxi 133he that is only 3 months old and the combustion box is filling with condense water manufactures have been out and said the flue is fitted at too steep angle, have adjusted flue to 3 deg incline, fault is still there looks like water is leaking in via the top white rope seal at the rear of the combustion box. manufactures are coming back again but does anyone know what is causing it, my feelings are that the main heat exchanger box will need to completely replaced, due to a manufacturing fault.