The sleep mode design is designed to simulate the natural wind scenario, with 1, 2 and 3 speeds automatically cycling every 20S. Maximum tilt angle of the ceiling<15°. In winter, the fan is usually set to rotate clockwise (reverse), which sucks the warm air near the ceiling upwards, allowing the warm air to be evenly distributed in the room to enhance heating comfort.Cubic feet per minute up to 4,500.