Are you sure there's no d.17? I think I have the right installation manual now for your boiler, which says there is. (I can upload, or provide a link if you want to check it is the right one.)
After reading it a bit more, I think there might be a second level you need to access to get some of the settings.
EDIT: d.17 seems to be in here
Second diagnostic level
• As described above in the first diagnostic level, scroll
through the diagnostic number d.97.
• Change the displayed value to 17 (password) and press the
"i" button. You are now in the second diagnostic level where
all information from the first diagnostic level (see table 10.2)
and the second diagnostic level (see table 10.3) is displayed.
Scrolling and changing values and exiting the diagnostic mode is done as described in the first diagnostic level.