Thanks, yup done that and the result is that the boiler no longer fires up, also unrelated or not but the whilst the water is kind of hot, it's not as hot as it should be. In any case, the engineer will come back tomorrow and sort it hopefully.
Hi, have a 29C model which had its PCS replaced by an enginer due to an electrical fault. He left the DHW pre-heat function on before leaving (the amber light), if I try and turn it off (as it was before the repair), it stops the boiler from heating up water, won't even fire up. Any suggestions...