Abstract: A facility for controlling moisture in grains provided with a grain storage silo conveniently installed on a hard flat floor and inside of which a raised floor drilled with air passageways is provided, determining an air chamber inside the silo and below the perforated floor, into which previously conditioned air is blown by an air heater, wherein the control of hot air blowing times is determined based on modeling and calculating carried out by a programmable controller operatively connected to an ambient air temperature sensor located outside the silo, an ambient relative humidity sensor located outside the silo and a temperature air sensor located into the air chamber inside the silo, thereby causing the application of different stages of drying, rewetting and maintenance of the first bottom layer of grain, ranging between an upper and lower moisture limits narrowing around the desired moisture while the drying progress, leading to an homogeneous final moisture content of all the grain bulk.