Cooling "220V Cooling Fan" fan "the eccentric" is the primary reason is the big noise loud noise loud noise primary reason is the primary reason is the primary cause loud noises. The center of gravity in the axial fan blades, when the job is very smooth, the sound is very small, but with the usual use of wear, a certain error occurs, the focus of the blades is not formed, "the eccentric" in the axis, such "220V Cooling Fan"after the change up to the equivalent of an oscillator (oscillator is the motor shaft plus a partial pain round), followed by the use of time longer,"220V Cooling Fan"gradually bearing wear, noise becomes aggravated sensation Big. Motor damage: cooling fan is an easy-to-consuming component, which depicts life after reaching the motor or motor damp several internal short circuit, overload, can lead to electrical power surges have damaged the appearance of such problems attributable to normal replacement fan can handle.