Hygiene unit for F5S-Therm self-closing thermostatic mixer for in-wall installation for shower facilities, for performing of automatic hygiene flushing and program-controlled thermal disinfection (additional bypass solenoid cartridge necessary) and storage of statistical data. Stainless steel cover plate 190 x 245 mm including sensor with control electronics and 6 V lithium battery (CR-P2) as well as solenoid valve cartridge. Activated water hygiene flushing (30 s), fixed interval time 24 hours and saving of statistical data. With option for parameterization and communication via optional, bidirectional remote control.