The Viega Fonterra Smart Control Standard, identified by part number X5V3A8 (Viega 789831), is a genuine OEM control unit designed for intelligent management of surface heating and cooling systems. This advanced unit supports up to 8 heating circuits operating at 24 V, ensuring optimal temperature regulation and energy efficiency. Key features include a self-learning heating curve, automatic hydraulic balancing, and integrated dew point monitoring. It also incorporates pump logic and offers an external input for switching between cooling and heating modes or for external temperature reduction. The unit is equipped with a bus connection for seamless system expansion and allows for connection of room thermostats, providing comprehensive control over your Fonterra system.