Hi Steve,
Thanks for that. The boiler has been serviced and the guy said that it could be an air lock but he didn't do anything about it. We tried to empty it again and than refill it and put the heating on and let air out of the radiators but it didn't fix the problem. Is there anything we can do to check what is wrong? The fault light is not showing. Do u know if it would be a costly repair? Maybe it's worth mentioning that we live in an area (Reading) where we have very hard water, could that have sth to do with it?
Many thanks.
Julia, June 2009