Hi, we moved into a house last year which has a 2 (now almost 3) year old Vaillant Combi Boiler (think it is the TurboMax). The water takes an absolute age to get hot - anything upwards of five minutes and even then it is never 'scalding' enough to get pans soaked etc! I have had two corgi engineers out who both reckon there is nothing wrong with it! Anyway, my latest problem is that it has today shut itself down with error code F28 - boiler block out due to insufficient gas supply or faulty valve etc. It would appear that the boiler has done this before as the previous owners have made a note of this error code on the front cover of the manual. Has anyone any ideas what this is and what is going on with this boiler. The heating side seems to work fine (obviously not today because it is totally off!) So far I aint very impressed with Vaillant!