most likely a problem with the water heater, could also be the thermistor (temp. sensor). Power off, remove back cover. Heater is located at bottom of drum. Disconnect wiring, undo central mounting nut and prise it out of its rubber seal - may require some effort. Replace heater, use sealant when refitting rubber seal and ensure it is fully pushed into the recess in the backplate.
Check out my site for info: www.2ndwave.co.uk/manual.html
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