@grooves- what version of the manual do you have? The one shown on the KL site is English Version 1.2 and says:
"Use only distilled water to fill the reservoir. Detergents, tap water, and other additives are not recommended and may react with materials used in the system or cause mineral build-up...."
I can check the manual that came with my machine- but the unit shown on their website (still up) looks pretty much identical to the unit I have here in terms of lack of switch on face panel, etc.