ISO 11855-7:2019

INTERNATIONAL ISO
STANDARD 11855-7
First edition
2019-09
Building environment design —
Design, dimensioning, installation and
control of embedded radiant heating
and cooling systems —
Part 7:
Input parameters for the energy
calculation
Conception de l'environnement des bâtiments — Conception,
dimensionnement, installation et contrôle des systèmes radiants
encastrés de chauffage et de refroidissement —
Partie 7: Paramètres d'entrée pour le calcul de la performance
énergétique
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
4.1 Symbols . 2
4.2 Subscripts . 2
5 Basic formula . 2
6 Determination of input parameters for the energy efficiency of heating and cooling
emission systems . 3
Annex A (informative) Calculation example . 5
Bibliography . 7
Foreword
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electrotechnical standardization.
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This document was prepared by Technical Committee ISO/ TC 205, Building environment design.
A list of all parts in the ISO 11855 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv © ISO 2019 – All rights reserved

Introduction
The radiant heating and cooling system consists of heat emitting/absorbing, heat supply, distribution
and control systems. The ISO 11855 series deals with the embedded surface heating and cooling system
that directly controls heat exchange within the space. It does not include the system equipment itself,
such as heat source, distribution system and controller.
The ISO 11855 series addresses an embedded system that is integrated with the building structure.
Therefore, the panel system with open air gap, which is not integrated with the building structure, is
not covered by this series.
The ISO 11855 series is intended to be applied to systems using not only water but also other fluids or
electricity as a heating or cooling medium.
The object of the ISO 11855 series is to provide criteria to effectively design embedded systems. To do
this, it presents comfort criteria for the space served by embedded systems, heat output calculation,
dimensioning, dynamic analysis, installation, operation and control method of embedded systems.
The ISO 11855 series consists of the following:
— Part 1 specifies the comfort criteria which should be considered in designing embedded radiant
heating and cooling systems, since the main objective of the radiant heating and cooling system is
to satisfy thermal comfort of the occupants.
— Part 2 provides steady-state calculation methods for determination of the heating and cooling
capacity.
— Part 3 specifies design and dimensioning methods of radiant heating and cooling systems to ensure
the heating and cooling capacity.
— Part 4 provides a dimensioning and calculation method to design Thermo Active Building Systems
(TABS) for energy-saving purposes, since radiant heating and cooling systems can reduce energy
consumption and heat source size by using renewable energy.
— Part 5 addresses the installation process for the system to operate as intended.
— Part 6 shows a proper control method of the radiant heating and cooling systems to ensure the
maximum performance which was intended in the design stage when the system is actually being
operated in a building.
1)
— Part 7 presents a calculation method for the product specific input parameters for ISO 52031 .
1) Under preparation. Stage at time of publication: ISO/DIS 52031:2019.
INTERNATIONAL STANDARD ISO 11855-7:2019(E)
Building environment design — Design, dimensioning,
installation and control of embedded radiant heating and
cooling systems —
Part 7:
Input parameters for the energy calculation
1 Scope
This document specifies procedures and conditions to enable the heat flow in water-based and
electrical surface heating and cooling systems to be determined relative to the medium differential
temperature for systems. The determination of thermal performance of water-based surface heating
and cooling systems and their conformity to this document is carried out by calculation in accordance
with design documents and a model. This enables a uniform assessment and calculation of water-based
surface heating and cooling systems.
The surface temperature and the temperature uniformity of the heated/cooled surface, nominal heat
flow density between water or electrical heated layer and space, the assoc
...