How to fix my UNIDARE Storage Heaters - my Baby is cold!?

I have recently moved here and we have 2 UNIDARE Storage heaters - Livingroom (WMC712N) and Bedroom (STHS170A). I was not aware - not sure I still am how these machines work as they are suppose to store heat and throw this out only when you have them switched on overnight - its beyond me as its also suppose to be a Convector heater - whats that?!
My wife had some baby clothes on these to dry off and then the next day they stopped working. Somebody said I may have to open them up (Dear God!) and click something to reset! Please, please can someone advise me in the simplest way how I can fix this - we have a baby at home and your advise will heartly be appreciated! Thank you