I remember the Cobe C2 we returned from home patients who smoked in the 1980's at home. The lines were brown & the smell was awful. I did manage to spray the bottom panel & the nicotine ran off. The lines were replaceable & were replaced inside & out. However the electronic boards & wiring were not. We just did our best & sprayed hospital air freshener inside & hoped the next patient couldn't smell it. The brown nicotine coated all the wiring. The treatment cabin's were just as bad & the ceilings were brown too.
It's always worse when the machine has a cooling fan sucking the smoke in too.
We have had other machines returned with nicotine smells but I think more patients smoked in the 1980's than now.
I can remember cleaning the screen of a TV with a cloth & seeing how much nicotine was on it & how clear the TV screen was after too.
I don't remember any machines not working due to Nicotine damage. I do remember working in a certain patients homes in thick smoke when both husband & wife were puffing away. I did feel sorry for the parrot at this particular home as it must have had emphysema!
This article is interesting.
https://www.sunderlandecho.com/news/couple-left-fuming-after-theyre-told-aps800-tv-has-been-ruined-by-them-smoking-369836