Anyone Know (stupid question in this excellent forum) whats causing ice to form around the freeer Fan /cowling on a Zanussi ZX99/5SI. Prod 92840533 one of the big Frost Free jobbies. No ice forming arounf the 2 channels in the evaporator tray that allow air to or back from the fridge, just every couple of weeks ice forming around fan cowling stopping the fan circulating air to the fridge section Cheers for youre help.