A hot melt adhesive system includes a supply container for storing adhesive particulate, a transfer pump operatively connected to the supply container, a transfer hose operatively coupled to the transfer pump, and a blocking member. The blocking member is movable between a first position in which stored adhesive particulate and air are permitted to be withdrawn from the supply container into the transfer hose, and a second position in which the stored adhesive particulate is blocked from passing through the transfer hose while air is permitted to pass therethrough to flush the transfer hose of residual adhesive particulate.