A method includes determining how to adjust one or more manipulated variables using at least one model. The one or more manipulated variables are associated with a supply of conditioned air for drying one or more objects. The method also includes generating one or more control signals to control one or more controlled variables associated with the supply of conditioned air. The one or more controlled variables include temperature, dewpoint, and/or humidity of the conditioned air. The one or more manipulated variables include a flow of heated material (like steam) used to condition the conditioned air. The one or more manipulated variables could also include a number of active units in a humidifier. Generating the one or more control signals could include accumulating adjustments associated with the humidifier and generating a control signal to alter the number of active units in the humidifier when the accumulated adjustments exceed a threshold.