Condensation is normal and you will get water in the tray. There could be a few reasons why you have a lot of water though, door may not seal correctly allowing warm air in, recently defrosted and water not evaporated from tray.
Suggest you dry out tray and see if water returns to same level, if it does then it is not evaporating from tray. Try turnig Temp colder slightly.
John, September 2008
