Method of cleaning a spray device

A device for diffusing sprayed liquid in a reception zone, wherein the device comprises:

• a vessel suitable for containing a liquid for spraying;
• at least one diffuser of sprayed liquid that is arranged in the vessel;
• heater means, such as a heater resistance element, arranged in the vessel, preferably closer to a bottom of the vessel than to a top of the vessel;
• a pipe situated outside a circuit for diffusing sprayed liquid in the reception zone and communicating, preferably directly, with the vessel;
• and
• control means for use during a stage of operation of the device in which the device is not diffusing liquid in the reception zone to cause the liquid contained in the vessel to be heated to a predetermined temperature, preferably higher than 60° C., in particular lying in the range 65° C. to 80° C., and to cause the liquid to be drained from the vessel via the pipe.