Had the E05 error on my Hoover Optima OPH714D. Replaced the NTC probe thermostat (approx ÂŁ12) and has been fine since. Not sure the part was faulty, but was heavily limescaled, so may be worth checking that before you buy a new one. Very easy to access & replace, 2 screws and remove a wiring clip.
Martin
December 2010
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