" I don't remember heating, which is much simpler anyway, to have similar problems." On the contrary, it is way too warm in the trains in winter and badly vent

" I don't remember heating, which is much simpler anyway, to have similar problems." On the contrary, it is way too warm in the trains in winter and badly vented. And you cannot change anything about it, because for safety reasons it is no longer possible to open a window even a tiny little bit. (And sometimes the AC is too cold in summer.)