I'm new to this forum and not sure if my last post " posted " I've got a problem with a potterton boiler the central heating engineer who I've used before says my problem could be one of many things and trial and error it's a potterton performa 24 the hot water is fine but there's no heating. There is a rod that operates the micro switch on what I think is the diverter valve that is permantley on which seems like the obvious fault. But if I pay for that to be changed and as he says it's not that but something else and then maybe something else it may be wiser to have a new boiler fitted.. can you advise please thanks in advance Kevin