Your link calls them split units and then concludes that they discharge condesate water outside; the water condenses on the cold coil - the evaporator?
I bought a house with oil heat and a furnace indoors adjacent the garage in an alcove; come summer the house became unbearably hot around midnight as the sucked-up heat in the red brick veneer began to radiate to the interior.
A quick trip to Montgomery Wards, a few hours spent in a 130F attic and one weekend later I was the proud owner of a central cooled home.
Everything went according to plan right up to the time the evaporator coil started dripping onto the concrete floor with no drain.
Like any good DYR’, I dragged a 35 gallon galvanized trashcan over under the drain pipe and went to bed.
The next morning I went out to the garage to confront 250 pounds of fresh H2O.
Back to the store for some hose and a small pump and the whole thing worked flawlessly right up to the day the mama racoon took up residence under the condenser slab - but that’s another story.
I know one guy around here who has his mini-split in the attic; our compressors are outside, and we had the contractor put in drain tubes and we catch the water and use it on our landscaping.