DIN EN ISO 11855-1:2026-05

This part of ISO 11855 specifies the basic definitions, symbols, and comfort criteria for embedded radiant heating and cooling systems. It is part of the ISO 11855 series of standards. This series of standards describes an embedded system that is incorporated into the building structure. Therefore, surface heating and cooling systems with open-air gaps that are not incorporated into the building structure are not covered by this series of standards. The ISO 11855 series of standards apply to water-based embedded surface heating and cooling systems in buildings. It applies to systems that use not only water but also other liquids or electricity as heating and cooling media. The ISO 11855 series is not applicable for testing of systems. The methods do not apply to heated or chilled ceiling panels or beams.. This document EN ISO 11855-3:2021 + A1:2023 has been prepared by Technical Committee ISO/TC 205 "Building environment design" in collaboration with Technical Committee CEN/TC 228 "Heating systems and water based cooling systems in buildings", the secretariat of which is held by DIN (Germany). Since November 2024 the EN ISO 11855 series of standards at CEN has been assigned to CEN/TC 130 "Space heating and/or cooling appliances without integral thermal sources", the secretariat of which is UNI (Italy). The responsible national standardization committee is Working Group NA 041-01-69-15 AK "Integrierte Flächenheizungen und -kühlungen (SpA CEN/TC 130/WG 9 und ISO/TC 205/WG 8)" ("Integrated surface heating and cooling (Mirror committee CEN/TC 130/WG 9 and ISO/TC 205/WG 8)") at DIN Standards Committee Heating and Ventilation Technology and their Safety (NHRS).