Abstract: A process and device for cleaning a rotary regenerative heat exchanger with a rotating part and a storage mass, for the transfer of heat from a higher-temperature, contaminated gas stream to a lower-temperature clean gas stream, in which upon reduction of the rotatory speed of the rotating part, jets of a cleaning agent and, immediately thereafter, jets of a gaseous drying agent, are sprayed onto the storage mass, with a continuous or step-wise radial displacement of the jets from the circumference to the center of the rotating mass and vice versa. The device includes a carriage, which is guided and driven radially over the storage mass. At least one nozzle each for a cleaning agent and a drying agent are on the carriage. A drive is associated with the rotor for establishing variable running speeds and lower cleaning speeds and for varying the rotatory speed of the rotor depending on the position of the carriage between the center and the circumference.