Concealed controller for time-dependent heating and cooling regulation of 2-pipe and 4-pipe systems in hotels, residential, and commercial spaces. Adaptable to almost all surface-mounted switch programs through various variants. Up to 5 valve actuators (normally open or closed) can be controlled per output. In 2-pipe operation, the operating mode can be switched via an external contact (change-over), temperature sensor, or in the menu. The clock can be used as a master for other controllers for ECO switching. The energy-saving function (ECO) or frost protection (standby) can be activated via an external contact. Alternatively, the controller's inputs can be configured for an external temperature sensor (weighting between internal and external sensor can be adjusted) or a dew point sensor (TPS). A 0-10 V interface allows for speed control of a fan (EC fan).