optimax

What causes the diverter valve to operate? I have replaced mine a couple of times, but the rads still getting warm when I draw hot water. I assume the diverter valve is not operating. But what triggers it to shut off?. I'm looking for a problem earlier on in the process I guess?

Hi, I'm getting a F05 fault and been trying to diagnose..... Rang feroli and they've talked me through checking a few settings in the service menu, to which has not proven to work, this then leaves a replacement PCB....? Seen re-conditioned ones one ebay for £60, although a bit apprehensive...