Bosch kgu3220 fridge-freezer with major ice build-up inside freezer ?

I had the same problem. Bosch told me to turn the appliance off for a few hours because the pipe that the excess water goes through to the back of the freezer may have frozen up. However, I pulled the appliance away from the wall and had a look around the back. Behind the freezer you will see a plastic tray that the excess water should go into. There is then a tube from the bottom of the back of the freezer which goes into the tray. Gently remove this tube from the freezer and test it under a tap to make sure water can run through it. If not it is blocked. Use some wire or a skewer to unblock it and then clean it in some hot soapy water and replace at back of freezer. In my case the tube was blocked with gunk and not frozen water so defrosting for a few hours would have made no difference

Jane Stockdale
January 2010