May be useful: http://www.hygenadiplomatspares.co.uk/cgi-bin/jvfident/shop/
You need to know the model. Look diligently for a rating plate (the page above gives some hints)
They will charge for a manual so you could also do a Google search for "'model' manual" - replacing 'model' with your model number - probably something like ADP3240 - but having tried a few searched for Hygena manuals I wouldn't hold out much hope
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April 2015