Hygiene unit for F5L single lever mixer, projection 125 mm, for performing automatic hygiene flushing and program-controlled thermal disinfection. Function block with 2 solenoid valve cartridges and an electronic control unit for installation in walls with flush box and cover made of plastic 150 x 80 mm, for battery or mains operation, 6 V DC. Activated water hygiene flushing, fixed interval of 24 hours and saving of statistical data. With option for parameterization and communication via optional, bidirectional remote control.