Hi there, this is a common problem it will most likely be the thermostat sensors located behind the rear cover. Unplug the unit observing all the usual safety precautions, remove the rear cover there will be 2 sensors round in sjaoe about the size of a 20p piece one is the high temp sensor the other low temp. You can usually get replacement parts for around £15, they can easily be replaced.
Hugh, January 2007
