You will first need to open the brush. Remove the chrome foot plate around the brush roller, then remove the clear plastic belt cover. Next remove the brush roller and belt. Remove all the remaining screws in the bottom of the brush and open the case. The wheel is held in place by a metal washer that clips over the wheel stem. Pinch the stem together and the ring will come off, you can now remove the wheel. To replace the wheel, reverse the process.