Vaestertorp

Someone who can help me with this: I have this 80:s old school ECC with green digital numbers in screen and buttons for control.

The problem is that it always starts at 85 = warmest. I have tried googling and thoroughly reading both my Haynes and Chilton manuals + trying to find a wiring diagram.

So, somebody please
- with a good diagram
or
- knowing if I am doing something wrong in setting (how to?)
or
- knowing if there is a memory chip or secret fuse and how to check it?

or other ideas?

Thanks in advance//