Electromechanical room temperature controller in a super-flat surface-mounted housing (only 13.9 mm deep) for controlling or monitoring temperatures in offices, living rooms and hotels. The thermal feedback achieves a very precise switching difference. The setting range can be changed using the range restriction located under the setting knob. The device is mounted using surface/wall mounting (4-hole fastening on flush-mounted box). Suitable for hot water heating systems. The device has a heating display and an ON/OFF switch. When the ECO input is connected to 230 VAC, the temperature is regulated to a temperature approx. 3 K lower (night-time reduction).