EN ISO 11855-2:2021

Building environment design - Embedded radiant heating and cooling systems - Part 2: Determination of the design heating and cooling capacity (ISO 11855-2:2021)

This document specifies procedures and conditions to enable the heat flux in water-based 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 flux between water and space, the associated nominal medium differential temperature, and the field of characteristic curves for the relationship between heat flux and the determining variables are given as the result.
This document includes a general method based on finite difference or finite element Methods and simplified calculation methods depending on position of pipes and type of building structure.

Umweltgerechte Gebäudeplanung - Flächenintegrierte Strahlheizungs- und -kühlsysteme - Teil 2: Bestimmung der Auslegungs-Heiz- bzw. Kühlleistung (ISO 11855-2:2021)

Dieses Dokument legt Verfahren und Bedingungen fest, welche die Bestimmung der Wärmestromdichte von Flächenheiz  und  kühlsystemen mit Wasserdurchströmung bezüglich der Heiz  und Kühlmittel¬übertemperatur für diese Systeme ermöglichen. Die Bestimmung der Wärmeleistung von Flächenheiz  und  kühlsystemen mit Wasserdurchströmung und ihrer Übereinstimmung mit diesem Dokument wird durch Berechnung nach den Planungsdokumenten und einem Modell vorgenommen. Dies ermöglicht eine einheitliche Bewertung und Berechnung von Flächenheiz  und  kühlsystemen mit Wasserdurchströmung.
Das Ergebnis daraus sind die Oberflächentemperatur und Temperaturgleichmäßigkeit der beheizten bzw. gekühlten Oberfläche, die Nenn-Wärmestromdichte zwischen dem Wasser und dem Raum, die zugehörige Nenn-Heiz  bzw.  Kühlmittelübertemperatur und das Kennlinienfeld für die Beziehung zwischen Wärme¬stromdichte und den entscheidenden Variablen.
Dieses Dokument enthält ein allgemeines Verfahren, beruhend auf Finite-Differenzen- oder Finite-Elemente-Methoden und vereinfachten Berechnungsmethoden, abhängig von der Position der Rohre und der Art der Gebäudestruktur.

Conception de l'environnement des bâtiments - Systèmes intégrés de chauffage et de refroidissement par rayonnement - Partie 2: Détermination de la puissance calorifique et frigorifique à la conception (ISO 11855-2:2021)

Le présent document spécifie les modes opératoires et conditions permettant la détermination du flux thermique des systèmes de chauffage et de refroidissement de surface à eau en fonction de l’écart de température du medium pour les systèmes. La détermination de la performance thermique des systèmes de chauffage et de refroidissement de surface à eau et de leur conformité au présent document est effectuée par calcul d’après les documents de conception et un modèle. Cela permet une évaluation homogène et un calcul des systèmes de chauffage et de refroidissement de surface à eau.
Les résultats obtenus sont: la température de surface et l’homogénéité de la température de la surface chauffée/refroidie, le flux thermique nominal entre l’eau et le local, l’écart de température nominal du medium associé et la famille de courbes caractéristiques de la relation entre le flux thermique et les variables d’influence.
Le présent document inclut une méthode générale fondée sur les méthodes des différences finies ou des éléments finis et des méthodes de calcul simplifiées dépendant de la position des tuyaux et du type de structure du bâtiment.

Načrtovanje notranjega okolja v stavbah - Vgrajeni sevalni ogrevalni in hladilni sistemi - 2. del: Določanje načrtovane grelne in hladilne moči (ISO 11855-2:2021)

Ta dokument določa postopke in pogoje za določevanje toplotnega toka v ploskovnih sistemih za ogrevanje in hlajenje z vodo glede na temperaturo razlike medija za sisteme. Določevanje toplotne učinkovitosti ploskovnih sistemov za ogrevanje in hlajenje z vodo in njihove skladnost s tem dokumentom se izvaja z izračunom v skladu s projektno dokumentacijo in modelom. To omogoča enotno oceno in izračun ploskovnih sistemov za ogrevanje in hlajenje z vodo. Kot rezultat so podani temperatura površine in enakomernost temperature ogrevane/hlajene površine, nazivni toplotni tok med vodo in prostorom, povezana nazivna temperaturna razlika medija in področje karakterističnih krivulj za povezavo med toplotnim tokom in določanjem spremenljivk. Ta dokument vsebuje splošno metodo na podlagi končne razlike ali končnega elementa metod in poenostavljene računske metode glede na položaj cevi in vrste stavbne konstrukcije.

General Information

• Status: Published
• Publication Date: 05-Oct-2021
• Withdrawal Date: 29-Apr-2022
• ICS: 91.040.01 - Buildings in general
• Technical Committee: CEN/TC 228 - Heating systems in buildings
• Drafting Committee: CEN/TC 228 - Heating systems in buildings
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 06-Oct-2021
• Completion Date: 06-Oct-2021
• Ref Project: SIST EN ISO 11855-2:2021 - Building environment design - Embedded radiant heating and cooling systems - Part 2: Determination of the design heating and cooling capacity (ISO 11855-2:2021)

Relations

• Replaces: EN ISO 11855-2:2015 - Building environment design - Design, dimensioning, installation and control of embedded radiant heating and cooling systems - Part 2: Determination of the design heating and cooling capacity (ISO 11855-2:2012)
• Effective Date: 10-Oct-2018
• Amended By: EN ISO 11855-2:2021/A1:2023 - Building environment design - Embedded radiant heating and cooling systems - Part 2: Determination of the design heating and cooling capacity - Amendment 1 (ISO 11855-2:2021/Amd 1:2023)
• Effective Date: 06-Oct-2021

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-2021
Nadomešča:
SIST EN ISO 11855-2:2015
Načrtovanje notranjega okolja v stavbah - Vgrajeni sevalni ogrevalni in hladilni
sistemi - 2. del: Določanje načrtovane grelne in hladilne moči (ISO 11855-2:2021)
Building environment design - Embedded radiant heating and cooling systems - Part 2:
Determination of the design heating and cooling capacity (ISO 11855-2:2021)
Umweltgerechte Gebäudeplanung - Flächenintegrierte Strahlheizungs- und -
kühlsysteme - Teil 2: Bestimmung der Auslegungs-Heiz- bzw. Kühlleistung (ISO 11855-
2:2021)
Conception de l'environnement des bâtiments - Systèmes intégrés de chauffage et de
refroidissement par rayonnement - Partie 2: Détermination de la puissance calorifique et
frigorifique à la conception (ISO 11855-2:2021)
Ta slovenski standard je istoveten z: EN ISO 11855-2:2021
ICS:
91.140.10 Sistemi centralnega Central heating systems
ogrevanja
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 11855-2
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2021
EUROPÄISCHE NORM
ICS 91.040.01 Supersedes EN ISO 11855-2:2015
English Version
Building environment design - Embedded radiant heating
and cooling systems - Part 2: Determination of the design
heating and cooling capacity (ISO 11855-2:2021)
Conception de l'environnement des bâtiments - Umweltgerechte Gebäudeplanung - Flächenintegrierte
Systèmes intégrés de chauffage et de refroidissement Strahlheizungs- und -kühlsysteme - Teil 2: Bestimmung
par rayonnement - Partie 2: Détermination de la der Auslegungs-Heiz- bzw. Kühlleistung (ISO 11855-
puissance calorifique et frigorifique à la conception 2:2021)
(ISO 11855-2:2021)
This European Standard was approved by CEN on 10 September 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11855-2:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 11855-2:2021) 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.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by April 2022, and conflicting national standards shall be
withdrawn at the latest by April 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11855-2:2015.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 11855-2:2021 has been approved by CEN as EN ISO 11855-2:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 11855-2
Second edition
2021-09
Building environment design —
Embedded radiant heating and cooling
systems —
Part 2:
Determination of the design heating
and cooling capacity
Conception de l'environnement des bâtiments — Systèmes intégrés de
chauffage et de refroidissement par rayonnement —
Partie 2: Détermination de la puissance calorifique et frigorifique à la
conception
Reference number
ISO 11855-2:2021(E)
©
ISO 2021
ISO 11855-2:2021(E)
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

ISO 11855-2:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 1
5 Concept of the method to determine the heating and cooling capacity .3
6 Heat exchange coefficient between surface and space . 4
7 Simplified calculation methods for determining heating and cooling capacity or
surface temperature . 6
7.1 Universal single power function . 7
7.2 Thermal resistance methods . 9
8 Use of basic calculation programmes .12
8.1 Basic calculation programmes .12
8.2 Items to be included in a complete computation documentation .13
9 Calculation of the heating and cooling capacity .13
Annex A (normative) Calculation of the heat flux .14
Annex B (informative) General resistance method .36
Annex C (informative) Pipes embedded in wooden construction .42
Annex D (normative) Method for verification of FEM and FDM calculation programmes .50
Annex E (normative) Values for heat conductivity of materials and air layers .53
Annex F (informative) Maximal surface temperatures for floor heating systems .55
Bibliography .56
ISO 11855-2:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 205, Building environment design, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC
228, Heating systems and water based cooling systems in buildings, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 11855-2:2012), which has been
technically revised.
The main changes compared to the previous edition are as follows:
— update of the figures for type A and C,
— update of the thermal, relevant material characteristics,
— editorial corrections.
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
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

ISO 11855-2:2021(E)
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 applicable to water-based embedded surface heating and cooling systems
in buildings. The ISO 11855 series
...