I know, ferroli again(bag of s**t) seems to be operating the heating constantly but stat is not set to call, Hot water demand symbol appears to come on though, with no taps open. Any suggestions?
Linked it out mate, made no difference, I reckon it's the diverter or PCB the reason why I say this is I've un plugged the flow sensor and It still fires for hot water with no demand.
Well that's what I thought it was but I disconnected the DHW flow sensor and it didn't stop it.
This one has a plate heat ex as well mate not the direct one.
i'd be looking at a board fault if all controls removed including flow sensor. As pants boiler as they are, when I've needed to speak to their technical they've always been helpful and do pick up the phone reasonably quick. They'll be able to run you through some quick tests to be sure as I reckon they don't come cheap.
I have had some luck called ferolli said if I put into eco it would stop the pre heat and stop it firing constantly but as I suspected he was lying when he said this would solve the heat passing to the central heating when the taps came on.
so basically it worked ok for a day and then no hot water at all but still called and fired for hot water it was just heating the central heating primaries so in conclusion as you say logic dictates that it must be the diverter sticking.