"Il y a la climatisation dans la chambre ?"
Translation:Is there air conditioning in the room?
"des/de" can't be both the plural indefinite article and a partitive aticle.
"des/de" is not a partitive article. Partitive means "part of something uncountable", so it excludes plurals.
Only a few exceptions could be considered for words only used in the plural like "des épinards", but it's not worth changing the nature of "des".
As soon as you have one single plural uncountable noun or one single plural mass noun in a language then a plural partitive article is also required.
French has tens of plural uncountable nouns, and I don't know how many plural mass nouns.
If the French plural partitive article is not "des", then what is it?
My apologies to Collins:
They, at least, do understand.