Air conditioning system

An air conditioning system 2 comprising: at least one piping circuit 20, inside which a predetermined gas flows; at least one compressor 21; at least one condenser 22; at least one pressure changing organ 23; at least one evaporator 24; at least one sanitization device 3, adapted to sanitize the air conditioning system 2 by means of at least one disinfectant substance "S" and is permanently built-in in system 2 itself.