My boiler failed new year day, would not open main gas solenoid valve, so after some indepth testing, new printed circuit board required. New board ordered 8am on the 2nd, board arrived, just before 1pm on the 3rd. A nice warm house by 1.30pm. Replacement pcb very easy to fit. I now have one happy wife ! Priceless. A great servìce by the supplier.