I've been having problems with my combi boiler lately. It's a Biasi M110.32SM/E. The central heating works fine with no problems at all, but the hot water is a bit temperamental. In brief, sometimes when I turn on a hot water tap only cold water comes out. Or sometimes hot water comes out for a few seconds and then it starts to go cold, hot, cold hot, etc. There is a group of three lights on the boiler.... the left one is marked 'I', the middle is 'II', and the right one is 'III'. Usually when the hot water is working fine lights 'I' and 'III' flash green. But I've noticed that everytime the hot water stops working the middle light 'II' flashes red. I've also noticed that when the middle light flashes red and the hot water stops working, if I turn the tap on to full or quickly switch the central heating on then the red light disappears and the water starts heating up again. This trick doesn't always work, but it does a lot of the time. I'll be calling out a boiler engineer after the bank holiday but does anybody have any ideas of what the problem could be?? Cheers.