flashing 40 80 means low water pressure in the central heating system.have had this on my se80.had a leaking radiator. needle on pressure gauge at bottom left of boiler had dropped into the red zone.after repair to radiator the pressure was charged up to 1.5 using a filling loop, this on mine is a flexible pipe with a tap on joining the incoming supply to the heating return pipe next to it, under the boiler.
scott, January 2010
