In certain examples, a printing device comprises a print head, a dryer, a heat exchanger, a distribution system and a controller. The heat exchanger is coupled to an exhaust of the dryer to produce pre-heated air. The distribution system is coupled to the heat exchanger and a plurality of regions of the printing device. The controller causes the distribution system to distribute the pre-heated air from the heat exchanger among the plurality of regions based on an operating parameter of the printing device.