Hello all. I am asking for some advice regarding the lack of dhw from my heatline combi. Central heating is fine. But when I put the tap on for hot water there is nothing the boiler doesn't switch from heating to hit water. Could this be the diverter valve gone. As before it the dhw stopped working there was a distinct clattering noise from the boiler as it swiched from central heating to hot water. Any advice would be greatly appreciated. Thanks.