If you are getting no water at all to the taps it has nothing to do with the pcb on your boiler as the water just passes through the heat exchanger. The probem is something is preventimg water passing through your boiler. Try turning off the valve on the cold water inlet then loosen the connecting nut slightly on the boiler side then open cold valve slightly to see if any water is getting passed the valve first of all as it has a filter on it which may be blocked
james mcwilliams, June 2010