Siemens RVD 255/109-A (RVD255/109-A) is a multifunctional weather-compensated controller designed for regulating the temperature of heating water and the preparation of domestic hot water in applications with district heating connections. It is typically used in small to medium-sized residential and non-residential buildings as part of a transfer station. The controller offers a wide range of configuration options – the device provides multiple types of heating circuits and variants for DHW preparation, so by selecting the type of device, the necessary functions and basic settings are automatically activated. The control supports common operating modes (automatic / continuous operation / frost protection) and works with time programs.

Main Features

• Regulation of heating water temperature and control of DHW preparation in district heating systems.
• Control options: weather-compensated control, weather-compensated with room temperature influence, room control, and control based on heat demand.
• Support for multiple DHW preparation variants (indirectly heated storage tank, direct heating, common/separate exchanger, two-stage heating from the primary network).
• Control of direct and three-way valves, bypass valves, and pumps (including the possibility of speed regulation according to the application).
• Setting the desired room temperature with a rotary knob, other parameters via service lines.

Technical Specifications