Remove the bottom panel on the front - two plastic screws. In the middle is a black hose with a stopper in the end. Remove the stopper and drain the hose there can be quite a bit of water, upt o 20l if the pump is blocked. When this is drained unscrew the front of the pump on the left side. You can then access the pump and remove any blockage. I have done this many times, it is usually one of my daughters hairgrips.
Anthony, April 2006