Re halstead ace heating ok, no hot water.
Thanks for replies paul and Rob.
Was told by halstead to replace pcb,the customer bought it from partscenter I fitted it ,same fault.
Phoned halstead again.After going through again tracing fault he says to check the venturi,it was totally blocked,cleared it out and boiler works fine.No mention of this in the mIs and was not even mentioned on the first call.Customer ended up with a Â£150 pcb( i'm glad I did not buy it.)
I thought parts center do not sell these parts to non corgi but in this case I was glad.
Thanks for replies I will chalk this up to experience.