Realistically, your carpets will take about 2-4hrs to dry under normal conditions. Drying times do vary due to a number of factors. For instance, wool is more absorbent that man-made fibres, hence a woollen carpet will take longer to dry.
Weather is another determining factor. In hot weather, your carpets will dry rapidly compared to colder weather. Therefore we advise you to leave some sort of heating on to aid drying, especially when the humidity is high.