Abstract This paper evaluates the performance of the magnetic valve for solids when used as a combined distributor—downcomer (MDD) for fluidized beds of magnetic solids. Two kinds of MDD, the grate and the collar designs, are selected for study, and regimes of behavior are mapped out in the form of phase diagrams. The difference in behavior of these designs is contrasted, and is found to be great. Also studied in detail are the bed pressure drop, power requirements, and the mass flux through the MDD when the current is intermittently applied, and hence when the solids are allowed to drop from the bed in a controlled way. We conclude that either design of MDD can be made to operate satisfactorily, and this opens the door to the possibility of developing reliable trouble-free multistage fluidized beds for solids which contain magnetic materials.