Abstract: A flush valve, a dust collector provided with such a flush valve and a dust collection system, are disclosed. The flush valve includes a valve body and a valve spool. The valve body is internally provided with a fluid passageway. The valve body is provided with an inlet, a first outlet and a second outlet. The first outlet is fluidly connected to a device to be flushed. The valve spool includes a movable part, a fixed part and an elastic part, the fixed part being provided in the valve body, and the elastic part elastically connecting said fixed part to the movable part. One end of the movable part being provided with a first spool land for blocking the first outlet. The first spool land being configured to be pushed away from said first outlet by fluid in the fluid passageway when the pressure drops due to blockage.