No particular number as the ideal thermostat setting will vary depending on the age/efficiency of the appliance and the ambient temperature.
A midpoint setting would usually plunge the cabinet temperature well below freezing and guidance from the thermometer will allow you to fine tune to the correct temperature of minus 27 C over a period of a few days.
As your freezer unexpectedly defrosted, it has probably developed a fault...
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No particular number as the ideal thermostat setting will vary depending on the age/efficiency of the appliance and the ambient temperature.
A midpoint setting would usually plunge the cabinet temperature well below freezing and guidance from the thermometer will allow you to fine tune to the correct temperature of minus 27 C over a period of a few days.
As your freezer unexpectedly defrosted, it has probably developed a fault...