Thank you Andrew and John @Corona.
I’m looking at reviews (in Dutch!) and they are pretty good and the company does seem to be good at responding if there is an issue, so I’ll try contacting them. They have a good website in English with an English contact form.
When the temperature at night is in the 20s - as it can easily be here in July - an air conditioner that runs all night and won’t disturb would be a bonus. At the moment our guests put up with the free-standing ones which are noisy.