Conditioning device and method for drying and controlling the temperature of a ballast bed

Conditioning device (24) and method for drying and/or controlling the temperature of a ballast bed (12) of a railway track system (10), wherein the railway track system (10) has sleepers (14) resting on the ballast bed (12) and rails (16) resting on the sleepers, wherein the conditioning device has a bogie (30) for moving the conditioning device (24). An outlet nozzle (36) for blowing temperature-controlled air into the ballast bed (12) via at least one blowing-in region (26) positioned between two adjacent sleepers (14) is connected to the bogie (30), as is at least one cover plate (42) for essentially air-tight coverage of an upper side, pointing essentially in the direction counter to the direction of gravity, of a side strip (20), provided next to the sleepers (14) in the direction of travel, of the ballast bed (12). In a method for drying and controlling the temperature of a ballast bed (12) of a railway track system (10), an upper side of the ballast bed (12) and/or at least one sleeper (14) and at least one rail (16) are sealed in an essentially air-tight fashion outside a blowing-in region (26) before temperature-controlled air is blown into the ballast bed (12) via the blowing-in region (26).