Ian, sorry,yes ignition pcb. I think he was saying that the fan gets it's power from the main board and as the fan is only working intermittently then the main board must be at fault.
When the low water contents switch was bypassed the boiler worked flawlessly until the switch was replaced. Are you saying that if the problem is with the main board then I should still experience the same issue, even with the bypass?
When the low water contents switch was bypassed the boiler worked flawlessly until the switch was replaced. Are you saying that if the problem is with the main board then I should still experience the same issue, even with the bypass?