Hi I hope someone could help me diagnose my boiler please? My hot water is not working properly, it slowly got worse with lukewarm temperatures and was calling for the boiler when a tap was run but now it doesn't even call the boiler. I can get some hot water whilst the heating is on now. My thoughts were that the diverter diaphragm is stuck? But now questioning myself as would of thought it would call for hot water through the flow switch? Thanks if anyone can help!