Method of recovering a printhead when mounted in a printing device

An inkjet printing device for printing plots comprises a printhead (300), having a plurality of nozzles (310); a servicing unit (80) capable of applying recovery functions to said plurality of nozzles (310); a plurality of recovery functions (1940, 1980, 1990, 2060, 2040, 2020, 2195, 2185, 2160, 2177, 2167, 2165, 2280, 2270, 2265, 2250) for recovering said plurality of nozzles (310), wherein each recovery function of said plurality of recovery functions (1940, 1980, 1990, 2060, 2040, 2020, 2195, 2185, 2160, 2177, 2167, 2165, 2280, 2270, 2265, 2250) is associated to at least one cause of failure of a nozzle; detection means (1900) to detect the cause of failure of a nozzle based on how the failure evolved over time, and selecting means (1900), responsive to the cause of failure identified by the detection means, to select a recovery function from said plurality of recovery functions (1940, 1980, 1990, 2060, 2040, 2020, 2195, 2185, 2160, 2177, 2167, 2165, 2280, 2270, 2265, 2250), to be applied by said servicing unit (80). Said device further comprises means to select and execute at least one of said plurality of functions, responsive to the data stored in said memory means. A method of recovering a printhead mounted in an inkjet printing device; comprising the steps of defining a set of causes of failure for the printhead, checking if one or more nozzles (310) are failing, identifying the cause of failure of a failing nozzle within said set by observing how the failure evolved over time; based on the identified cause of failure, performing an appropriate function for recovering the failing nozzle (310).