Thanks again for the help.
For what it's worth I suspect that the machine is actually made by Fujitsu Seimens with a Medion label on it. Fujitsu were selling identical cased machines a few months before Medion brought theirs out through Aldi.
I am still not getting very far with Medion UK. A telephone shouting match with the receptionist to at least speak to someone who could help finally produced a voice who promised to call me back within the hour, he did, to tell me he would ring back by the end of the day, he did (at 7pm) to tell me he will ring me by lunchtime today. All this to tell me whether they will sell me a £30 inverter or not, never mind when!
Grrrr...
