Question about Electrolux Chill Flex Pro

There is no categorical answer, it depends very much on the house incl. insulation etc. In my attic flat, despite indoor temperatures of well over 30 degrees without cooling, it was always enough to run the unit in the evening and switch it off overnight. However, sometimes it was already >1 h, which also depends on the room. It is important that the exhaust air hose is laid in such a way that a lot of hot air does not come in again through the same opening, i.e. insulate and do not start too early.