Flush-mounted controller for time-dependent heating/cooling control of 2- and 4-pipe systems in hotel, residential and business premises. Can be adapted to almost all flat switch programs thanks to various variants. Up to 5 valve actuators (currentless open or closed) can be controlled per output. in 2-pipe operation, the operating mode can be switched over via an external contact (change-over), temperature sensor or 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 by an external contact. Alternatively, the inputs of the controller can be configured for an external temperature sensor (weighting between internal and external sensor can be set) or a dew point sensor (TPS). A fan (EC fan) can be speed-controlled via a 0 … 10 V interface.