BELLISSIMO HNTB65XL Instructions For Use And Installation page 11

Use and Care
Defrost mode
When set to 'Defrost' mode, the fan located at the back of the oven
circulates room temperature air around the food. This is
recommended for the defrosting of all types of food, but in
particular for delicate types of food which do not require heat, for
example: ice cream cakes, cream or custard desserts, fruit cakes,
etc. By using 'Defrost' mode, the defrosting time is approximately
halved.
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