Is reverse running really useful in winter?

Return or winter mode means that the air is pressed to the ceiling, flows along it to the walls, runs down there to the floor and is sucked in again under the fan by the resulting UInterpressure. Depending on the temperature difference, this only makes sense for a room height of up to 2.6 m.

Otherwise, the following happens: The air is pushed to the ceiling and runs down the walls. But since this air is warmer and therefore lighter than the room air, it is subject to natural buoyancy. Somewhere on the way down, the kinetic energy becomes less than the buoyancy and the air flows back under the fan, under which there is a negative pressure. This presses it back up again. Thus, however, it never reaches the ground. A "short circuit" occurs - the lower and most important part of the room is not reached with the warm main airflow.

Therefore, in high rooms, one always works with the forward or summer mode. Because whether from top to bottom or from bottom to top, the effect of mixing is always the same. However, it is important here - to avoid drafts - a good step control. In summer as fast as possible and in winter as slow as necessary.

Therefore, switching to winter operation or reverse operation is not useful for ceilings of 2.60 m or more.