ISO 11855-6:2018/Amd 1:2023

Overview

ISO 11855-6:2018/Amd 1:2023 is an amendment to the internationally recognized standard for building environment design. It specifically addresses the control aspects of embedded radiant heating and cooling systems. These systems use surfaces with embedded pipes, such as floors or walls, to provide efficient thermal regulation in buildings through radiant heat exchange. This amendment updates the control strategies to account for the thermodynamic properties that impact system responsiveness and energy efficiency.

The updated standard provides guidance on the design, dimensioning, installation, and particularly the control of these embedded systems. It emphasizes the importance of understanding surface heat capacities and their influence on control methods to optimize comfort and system performance.

Key Topics

• Heat Capacity and Thermal Response
  The amendment highlights the role of heat capacity of surfaces with embedded pipes (e.g., floor screeds) on system behavior. Different system types (III, V, I, II, IV) are categorized by thermal capacity and response time, assisting designers in selecting appropriate control strategies based on these properties.

• Control Strategy Adjustments
  Control approaches must consider parameters such as the heat carrier temperature, time response of the embedded system, and the thermal mass of the building itself. The amendment notes that building time constants typically exceed those of embedded radiant systems, affecting control timing and settings.

• System Components and Controls
  Figure A.1 illustrates a typical radiant floor header arrangement, including:

  • Heating and cooling generation units
  • Bypass and maintenance valves
  • Balancing and temperature control valves
  • Circulation pumps
  • Manifolds for supply and return
  • Water temperature sensors
  • Controllers for heat sources, main system control, and individual room temperature control

• Integration and Maintenance
  The standard also provides recommendations for the proper installation and maintenance of control system components to ensure reliability and precise temperature regulation.

Applications

• Residential and Commercial Buildings
  ISO 11855-6:2018/Amd 1:2023 is essential for engineers, architects, and HVAC professionals designing embedded radiant systems in homes, offices, schools, and other commercial buildings.

• Energy-Efficient Building Design
  By following the updated control guidelines, buildings can achieve improved energy efficiency, stable indoor climates, and enhanced occupant comfort-key drivers in sustainable design and green building certifications.

• Retrofitting and Modernization
  The amendment supports upgrading existing embedded radiant heating and cooling systems by improving control logic to respond more effectively to building load variations and user needs.

Related Standards

• ISO 11855 Series
  The amendment forms part of the broader ISO 11855 series, which covers the entire lifecycle of embedded radiant heating and cooling systems, including design, dimensioning, installation, and control.

• ISO 50001: Energy Management Systems
  Implementing ISO 11855-6 controls aligns with ISO 50001 principles by optimizing energy use in building environments.

• EN 1264 Heating Systems in Buildings
  Complementary European standards on embedded water-based heating and cooling systems offer further guidance on design and installation practices.

By adhering to ISO 11855-6:2018/Amd 1:2023, professionals can ensure that embedded radiant systems operate with maximum efficiency and responsiveness. This leads to enhanced thermal comfort, optimized energy consumption, and reliable system control, directly supporting sustainable and intelligent building design initiatives.