hallo driethenauer,
thank you for your kindly answer and for your effort to give an answer.
My question was addressed to the Viessmann service, not to other users of the forum....
even me on this time I'm in holydays, so i'm relaxed, you know???
I understand that maybe Viessmann on wekkend is closed, but I think theyr computer are not in vacancy!!!!
I guess no answer to this question, from theyr service....
I bought the manual that it's wrote in german, so Viessmann should sell his manual at least even in english, since we are european, and not everyone knows the german language.
Viessmann obviously doesn't care other markets, such as by the German market....that's all!!!
never mind, the life goes on.....
greetings from Italy