Smeg CS19ID-6 Instructions For Installation And Use Manual page 24

Instructions for the User
7.5 Defrosting
FUNCTION SELECTOR
THERMOSTAT SET ON 0
The air movement provided by the fan alone thaws foods more quickly.
The air circulating inside the oven is at room temperature.
Defrosting at room temperature has the advantage that the food's flavour
and appearance are retained intact.
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