Summer and winter mode
In many cases, it is the cooling effect we want with a ceiling fan, but many of the better fans on the market are also reversible. It is thus possible to set in which direction the blades should rotate. In this way, the warm air can both be pressed down to provide extra heat in winter or drawn up to give a cooling effect in summer. The warm air can be used better and provide more heat at ground level without raising the temperature in the room, which means that the heating cost is reduced in winter. Using a ceiling fan in winter is also an effective way to distribute the hot air evenly in the room from a fireplace or stove.
One fan is a construction intended to move gas. The fan usually consists of a motor that rotates a number of wing-like blades. When the blades rotate, a negative pressure arises on one side and a corresponding overpressure on the other side, whereupon the gas mixture is set in motion. Simpler fan designs are often used for cooling, for example in computers.
Fans for buildings can be divided into radial, axial and chamber fans. The different fans have different characteristics, which makes them suitable for different applications. Radial fans are most common in ventilation systems in buildings as they can generate relatively high pressures at relatively low flows. Axial fans are used to advantage in those contexts where large amounts of air need to be moved. In the mining industry, for example, axial fans are often used, often connected in series, as this provides the opportunity to move large amounts of air even at high pressures. Chamber fans are transverse radial fans, and thus take up less space, which is why they are often used as space is a limiting factor. However, this means a lower efficiency, which leads to higher electricity use.