Unless your refrigerator specifically states the dial means temperature, then the numbers will be on a scale of 1-5 or 1-7, with one being the warmest or least powerful. The highest setting will therefore be 5 or 7, which indicates the higher power the fridge will operate at, not the temperature as some people believe.  Therefore, the number should be set at 0-2 for emptier fridges, or if your fridge is regularly icing up.  3-5 or 3-7 should be reserved for fridges that are holding a lot of food the majority of the time.