I have a biasi combi boiler and don't seem to be getting any central heating, although the hot water is working fine. I think the problem started with the slider switch which appears to be broken, but now the clock isn't working on the timer. Is there an easy way to get behind the clock to set the position to ON manually, until a new slider switch for the timer arrives. I'm hoping that's where the problem lies - it's freezing here tonight and set to get worse!! Thanks for any help anyone can give me...