Hi,
It's a Vaillant Turbo boiler, functioning fine as regards to the central heating, but no longer supplying hot water? Even on maximum heat, it gets warm then cools down, then gets hot and then cools down again, its not possible to have a hot shower.
We are insured by British Gas - when they came, they said there was nothing wrong with it. Two years ago they changed the diverting valve, since then the problem started getting worse, any help? thanks
Ali, February 2010