CEN/TR 18341:2026

• Abstract:

  This document provides an overview of the standardization deliverables published and under development under the responsibility of CEN/TC 107. It defines the temperature ranges applicable to the intended use of these documents and establishes a classification system linking each document to its corresponding temperature range. Furthermore, it describes how estimation of service life of pipe systems is conducted based on the average operating temperature within service pipes, taking into account additional influencing conditions.

• Status: Published
• Publication Date: 30-Jun-2026
• ICS: 23.040.07 - Pipeline and its parts for district heat
• ICS: 23.040.99 - Other pipeline components
• Technical Committee: CEN/TC 107 - Pre-fabricated district heating pipe systems
• Drafting Committee: CEN/TC 107/WG 2 - Basic consideration
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 01-Jul-2026
• Due Date: 03-Jun-2026
• Completion Date: 01-Jul-2026
• Ref Project: SIST-TP CEN/TR 18341:2026 - District heating and cooling systems - Supplementary information on usage of CEN/TC 107 documents

• Referred By: EN ISO 17831-2:2025 - Solid biofuels - Determination of mechanical durability of pellets and briquettes - Part 2: Briquettes (ISO 17831-2:2025)
• Effective Date: 28-Jan-2026
• Referred By: EN ISO 17831-1:2025 - Solid biofuels - Determination of mechanical durability of pellets and briquettes - Part 1: Pellets (ISO 17831‑1:2025)
• Effective Date: 28-Jan-2026
• Referred By: EN ISO 17829:2025 - Solid biofuels - Determination of length and diameter of pellets (ISO 17829:2025)
• Effective Date: 28-Jan-2026
• Referred By: EN ISO 17225-8:2023 - Solid biofuels - Fuel specifications and classes - Part 8: Graded thermally treated and densified biomass fuels for commercial and industrial use (ISO 17225-8:2023)
• Effective Date: 28-Jan-2026

Overview

CEN/TR 18341:2026 is a technical report from the European Committee for Standardization (CEN) that offers comprehensive guidance on the use and classification of deliverables produced by CEN/TC 107 for district heating and cooling systems. This document clarifies which standardized documents apply to specific applications based on defined temperature ranges, facilitating their proper selection and implementation. It also outlines the methodology for estimating the service life of various pipe systems by referencing average operating temperatures, accounting for critical factors impacting longevity.

This standard is vital for professionals engaged in the design, installation, and maintenance of district heating and district cooling networks, supporting consistent quality across diverse system types and operational environments.

Key Topics

• Standardization Deliverables Mapping
  Provides an organized overview of all EN, TS, and TR documents developed or in progress by CEN/TC 107, linked to district heating and cooling pipelines.

• Temperature Range Classification
  Establishes a clear classification system relating each standard to applicable temperature ranges (from district cooling to high-temperature district heating), ensuring appropriate use of materials and design approaches.

• Pipe System Types
  Covers both rigid and flexible pipe systems, detailing their construction with steel, plastic, or reinforced service pipes for different thermal conditions.

• Service Life Estimation
  Explains how the expected lifespan of pipe systems is calculated based on the average operating temperature, using current standards and engineering principles.

• Guidance on Applicable Standards
  Provides practical advice for selecting the correct standards for design, installation, operation, and personnel qualification within district heating and cooling networks.

Applications

The guidance contained in CEN/TR 18341:2026 supports a range of practical applications across the district energy sector:

• System Design and Engineering
  Streamlines the process of matching the appropriate standard to project requirements, whether for new installations or upgrades to existing district heating or cooling networks.

• Material and Temperature Compatibility
  Ensures consistent quality and reliability by assigning clear standards based on pipe material and expected operating temperature, mitigating risks such as mechanical stress, buckling, or temperature-induced degradation.

• Service Life Planning
  Supports long-term infrastructure investment by enabling accurate predictions of pipe system longevity, factoring in average annual operating temperatures and quality control measures.

• Qualification of Personnel
  Clarifies the standards required for qualification testing of fitters and welders, supporting safer and more reliable system installation and maintenance.

• Adapting to Evolving Technologies
  Facilitates the integration of new products and materials into district energy systems, with standards now including polymeric pipes and lower temperature operations.

Related Standards

For optimal implementation and compliance, CEN/TR 18341:2026 should be used alongside the following key standards relevant to district heating and cooling systems:

• EN 253: Bonded single pipe systems for buried hot water networks
• EN 14419: Surveillance systems for district heating pipes
• EN 13941 (Parts 1 & 2): Design and installation of thermal insulated pipe systems
• EN 489 (Series): Joint casing assemblies for bonded pipe systems
• EN 15632 (Series): Factory-made flexible pipe systems for district heating
• EN 17415 (Series): Pipe systems for district cooling
• EN 17414 (Series): Flexible pipe systems for district cooling
• EN 17878 (Series): Flexible pipe systems with lower temperature profiles
• EN ISO 13760: Calculation method for cumulative damage (Miner's rule)

These standards provide the technical specifications, test methods, and requirements essential for reliability, efficiency, and safety in district heating and cooling networks across Europe.

By adhering to CEN/TR 18341:2026 and its related standards, industry professionals can ensure optimally designed, installed, and maintained district energy systems, supporting energy efficiency and system longevity.

SLOVENSKI STANDARD
01-september-2026
Sistemi daljinskega ogrevanja in hlajenja - Dodatne informacije o uporabi
dokumentov CEN/TC 107
District heating and cooling systems - Supplementary information on usage of CEN/TC
107 documents
Fernwärme- und Fernkälteverteilsysteme - Ergänzende Information zur Anwendung der
Dokumente des CEN/TC 107 "Fernwärme- und Fernkältesysteme"
Systèmes de chauffage urbain et de froid urbain - Informations supplémentaires relatives
à l'utilisation des documents du CEN/TC 107
Ta slovenski standard je istoveten z: CEN/TR 18341:2026
ICS:
23.040.07 Cevovodi za daljinsko Pipeline and its parts for
ogrevanje in njihovi deli district heat
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TR 18341
TECHNICAL REPORT
RAPPORT TECHNIQUE
July 2026
TECHNISCHER REPORT
ICS 23.040.99; 23.040.07
English Version
District heating and cooling systems - Supplementary
information on usage of CEN/TC 107 documents
Canalisations pour le chauffage urbain et réseaux d'eau Fernwärme- und Fernkälteverteilsysteme -
glacée - Informations supplémentaires sur l'utilisation Ergänzende Information zur Anwendung der
des documents du CEN/TC 107 Dokumente des CEN/TC 107 "Fernwärme- und
Fernkältesysteme"
This Technical Report was approved by CEN on 31 May 2026. It has been drawn up by the Technical Committee CEN/TC 107.

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, Türkiye 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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 18341:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Structure of standardization deliverables . 5
4.1 General . 5
4.2 Terminology in district heating and cooling pipe systems . 6
4.3 Surveillance systems . 6
4.4 Design and installation of thermal insulated rigid and flexible pipe systems . 7
4.5 Joint casing assemblies . 7
4.6 Qualification testing of fitter and PE-welder . 7
4.7 Bonded rigid single pipe systems for directly buried hot water networks . 7
4.8 Bonded rigid twin pipe systems for directly buried hot water networks . 7
4.9 Bonded rigid single pipe systems for directly buried cold water networks . 7
4.10 Factory-made flexible pipe systems for district heating . 7
4.11 Factory-made flexible pipe systems for district cooling . 8
5 Temperature ranges . 8
6 Service life . 10
Bibliography . 12
European foreword
This document (CEN/TR 18341:2026) has been prepared by Technical Committee CEN/TC 107 "District
heating and cooling systems", the secretariat of which is held by DS.
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.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
Introduction
CEN/TC 107 is responsible for the development, revision, and adaptation of standardization
deliverables within the domain of district heating and cooling systems. These deliverables include
European Standards (EN), Technical Spécifications (TS), and Technical Reports (TR). Since the
publication of its first standard, EN 253, in 1990, the committee has produced more than 26 deliverables
addressing various aspects of the sector.
In 2023, the scope of CEN/TC 107 was expanded to address emerging requirements in district heating
and cooling, with particular attention to system optimization, environmental considerations, and sector
coupling. This expansion also aligns with the activities of ISO/TC 341, thereby facilitating opportunities
for joint development of standards under the framework of the Vienna Agreement or through adoption.
Given the growing number of deliverables, there is a recognized need to provide clear guidance to users
regarding the availability and applicability of standards, technical spécifications, and technical reports
for district heating and cooling pipes, including the conditions under which these documents are used.
1 Scope
This document provides an overview of the standardization deliverables published and under
development under the responsibility of CEN/TC 107. It définés the temperature ranges applicable to
the intended use of these documents and establishes a classification system linking each document to
its corresponding temperature range. Furthermore, it describes how estimation of service life of pipe
systems is conducted based on the average operating temperature within service pipes, taking into
account additional influéncing conditions.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and définitions are listed in this document.
— ISO Online browsing platform: available at http://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
4 Structure of standardization deliverables
4.1 General
Figure 1 illustrates the standardization deliverables published and currently under development by
CEN/TC 107. It further indicates:
— which deliverables are of a superordinate nature and therefore generally applicable;
— the deliverables applicable to district heating pipelines and those applicable to district cooling
pipelines;
— the deliverables relevant to rigid pipe systems and those relevant to fléxiblé pipe systems.
Key
WI work item
EN European standard
TS technical spécification
SPS single pipe systems
TPS twin pipe systems
Figure 1 — Structure of standardization deliverables under the scope of CEN/TC 107
4.2 Terminology in district heating and cooling pipe systems
EN 17248 [1] provides a comprehensive set of terms and définitions related to district heating and
district cooling pipe systems. It serves as a reference to ensure consistent and clear communication
within the industry.
4.3 Surveillance systems
EN 14419 [2] spécifiés the requirements and installation of surveillance systems to monitor and
maintain the integrity of the district heating infrastructure.
4.4 Design and installation of thermal insulated rigid and flexible pipe systems
The EN 13941 series [3] provides requirements for the design and installation of directly buried bonded
pipe systems in district heating networks. EN 13941-1 [4] définés design principles, while EN 13941-2
[5] spécifiés installation practices.
NOTE Information on district cooling is being integrated into the current revision process.
4.5 Joint casing assemblies
The EN 489 series [6] provides spécifications for joint casing systems in district heating and cooling
applications. EN 489-1 [7] définés requirements for joint casing assemblies and thermal insulation in
bonded pipe systems, while EN 489-2 [8] spécifiés joint casing systems for factory-made fléxiblé pipe
systems.
4.6 Qualification testing of fitter and PE-welder
The EN 18213 (series) [9] establishes qualification requirements for personnel involved in the
installation of bonded single and twin pipe systems used in directly buried hot and cold water
networks, with EN 18213-1 [10] specifying the procedures and criteria for the qualification testing of
fittérs, EN 18213-2 [11] défining the requirements for the qualification testing of polyethylene (PE)
welders.
4.7 Bonded rigid single pipe systems for directly buried hot water networks
These are a category of standards providing spécifications for bonded single pipe systems in directly
buried district heating networks. EN 253 [12] définés requirements for factory-made pipe assemblies
with steel service pipes, polyurethane foam thermal insulation, and a polyethylene casing. EN 448 [13]
spécifiés fitting assemblies, EN 488-1 [14] covers shut-off valve assemblies, and EN 488-2 [15] définés
service valve assemblies.
4.8 Bonded rigid twin pipe systems for directly buried hot water networks
The EN 15698 series [16] provides spécifications for bonded twin pipe systems in directly buried district
heating networks. EN 15698-1 [17] définés requirements for factory-made twin pipe assemblies with
steel service pipes, polyurethane foam thermal insulation, and a polyethylene casing, while EN 15698-2
[18] spécifiés fitting and valve assemblies with the same construction.
4.9 Bonded rigid single pipe systems for directly buried cold water networks
The EN 17415 series [19] spécifiés requirements for factory-made components used in bonded single
pipe systems for directly buried cold water networks in district cooling applications. EN 17415-1 [20]
définés the requirements for pipe assemblies, EN 17415-2 [21] covers fitting assemblies, and EN
17415-3 [22] spécifiés the requirements for steel valve assemblies, ensuring that all components are
suitable for the spécific conditions of cold water distribution.
4.10 Factory-made flexible pipe systems for district heating
The standards on factory-made fléxiblé pipe systems for district heating cover classifications,
requirements, and test methods for both bonded and non-bonded systems with plastic or metal service
pipes.
The EN 15632 series [23] provides spécifications for fléxiblé pre-insulated pipe systems used in district
heating applications. EN 15632-1 [24] définés general requirements and system components, EN
Under preparation. Stage at the time of publication: prEN 489-2:2025.
Under preparation. Stage at the time of publication: prEN 18213-1:2025.
Under preparation. Stage at the time of publication: prEN 18213-2:2025.
15632-2 [25], spécifiés requirements for bonded systems, EN 15632-3 [26] covers non-bonded
systems, and EN 15632-4 [27] outlines test methods applicable to both configurations.
The EN 17878 series provides further spécifications for fléxiblé pipe systems with a lower temperature
profilé. EN 17878-1 [28] définés general requirements, EN 17878-2 [29] spécifiés performance criteria
and product characteristics, and EN 17878-3 [30]outlines applicable test methods.
NOTE For lower temperature profilé, see Figure 1 and Figure 2 .
CEN/TS 17889 [31] complements these standards by offering technical spécifications that support
harmonization in the design and application of fléxiblé pipe systems for district heating and
...