oSIST prEN 1856-2:2021

Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting flue pipes

This document specifies the characteristics of performance for rigid or flexible metal flue liners, rigid metal connecting flue pipes and their fittings used to convey the products of combustion from appliances to the outside atmosphere (including their supports) or the chimney.
This document specifies sootfire resistant flue liners, connecting flue pipes and fittings for combustion appliances burning solid, liquid and gaseous fuels and non-sootfire resistant flue liners, connecting flue pipes and fittings for combustion appliances burning liquid and gaseous fuels only.
NOTE   This means that flue liners, connecting flue pipes and fittings designated "O" are not suitable for combustion appliances burning solid fuel.
Vitreous enamelled connecting flue pipes are also covered by this document.
Rigid flue liners can be used as flue liners for renovation or adaptation of existing chimneys and as flue liners of custom built chimneys.
Flexible metal flue liners described in this document are exclusively for renovation or adaptation of existing chimneys. Flexible connecting flue pipes and extensible flexible products designed to be compressed or extended along their length are excluded from the scope of this document.
Single-wall and multi-wall system chimney products (chimney sections, chimney fittings and terminals, including supports) are covered by prEN 1856-1:2021, even if used as liners for existing chimneys or connecting flue pipes.

Abgasanlagen - Anforderungen an Metall-Abgasanlagen - Teil 2: Innenrohre und Verbindungsstücke aus Metall

Dieses Dokument legt die Leistungseigenschaften für starre und flexible Metallinnenrohre, starre Verbindungsstücke aus Metall und deren Formstücke fest, welche zur Abführung von Verbrennungsprodukten von Feuerstätten an die Außenluft verwendet werden (einschließlich ihrer Halterungen).
Dieses Dokument legt die Spezifikation von rußbrandbeständigen Innenrohren, Verbindungsstücken und Formstücken für Verbrennungseinrichtungen zur Verbrennung fester, flüssiger und gasförmiger Brennstoffe sowie von nicht rußbrandbeständigen Innenrohren, Verbindungsstücken und Formstücken für Verbrennungseinrichtungen nur zur Verbrennung flüssiger und gasförmiger Brennstoffe fest.
ANMERKUNG   Das bedeutet, dass die mit einem "O" gekennzeichneten Innenrohre, Verbindungsstücke und Formstücke nicht für Verbrennungseinrichtungen geeignet sind, in denen feste Brennstoffe verbrannt werden.
Emaillierte Verbindungsstücke sind ebenfalls Gegenstand dieses Dokuments.
Starre Innenrohre können auch als Abgasrohre zur Sanierung oder Querschnittsverminderung bestehender Abgasanlagen sowie als Abgasrohre für maßgefertigte Abgasanlagen verwendet werden.
Flexible Metallinnenrohre nach diesem Dokument werden ausschließlich bei Sanierung oder Querschnittsanpassung einer bestehenden Abgasanlage eingesetzt. Flexible Verbindungsstücke und ausziehbare flexible Produkte, die in ihrer Länge zusammengeschoben oder ausgezogen werden können, fallen nicht in den Anwendungsbereich dieses Dokuments.
Einschalige und mehrschalige System-Abgasanlagen (Abschnitte der Abgasanlagen, Formstücke und Aufsätze, einschließlich der Stützen) werden in prEN 1856-1:2021 behandelt. Dies gilt auch für Innenrohre von bestehenden Abgasanlagen oder für Verbindungsstücke.

Conduits de fumée - Prescriptions pour les conduits de fumée métalliques - Partie 2 : Tubages et éléments de raccordements métalliques

Le présent document spécifie les caractéristiques de performance des tubages métalliques rigides ou flexibles, des conduits de raccordement métalliques rigides et de leurs éléments de raccordement utilisés pour évacuer dans l'atmosphère extérieure les produits de combustion provenant des appareils (supports compris) ou du conduit de fumée.
Le présent document spécifie les tubages, les conduits de raccordement et les autres éléments de conduit résistants au feu de cheminée pour les appareils de combustion à combustibles solides, liquides et gazeux ainsi que les tubages, les conduits de raccordement et les autres éléments de conduit non résistants au feu de cheminée pour les appareils de combustion à combustibles liquides et gazeux uniquement.
NOTE   Cela signifie que les tubages, conduits de raccordement et autres éléments de conduit désignés « O » ne sont pas appropriés pour des appareils de combustion à combustible solide.
Les conduits de raccordement en émail vitrifié relèvent aussi du présent document.
Les tubages rigides peuvent être utilisés comme conduits intérieurs soit pour la rénovation ou l'adaptation de conduits de fumée déjà installés, soit pour les conduits de fumée construits sur site.
Les tubages métalliques flexibles décrits dans le présent document sont exclusivement destinés à la rénovation ou à l'adaptation des conduits de fumée déjà installés. Les conduits de raccordement flexibles et les produits flexibles extensibles conçus pour être comprimés ou déployés dans le sens de la longueur sont exclus du domaine d'application du présent document.
Les systèmes de conduits de fumée simple paroi et multi-parois (éléments droits, éléments de raccordement et terminaux, supports compris) sont couverts par le prEN 1856-1:2021, même lorsqu'ils sont utilisés en tant que tubages pour des conduits de fumée ou des conduits de raccordement existants.

Dimovodne naprave - Zahteve za kovinske dimovodne naprave - 2. del: Kovinske tuljave in povezovalni dimovodi

General Information

• Status: Not Published
• Public Enquiry End Date: 05-Sep-2021
• ICS: 91.060.40 - Chimneys, shafts, ducts
• Technical Committee: POZ - Požarna varnost
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 10-Jun-2021
• Due Date: 28-Oct-2021
• Completion Date: 02-Aug-2021
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Mandate: M/105 - Mandate to CEN/CENELEC concerning the execution of standardization work for harmonized standards on chimneys, flues and specific products
• Ref Project: prEN 1856-2 - Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting flue pipes

Relations

• Revised: SIST EN 1856-2:2009 - Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting flue pipes
• Effective Date: 24-Feb-2021
• Revised: SIST EN 1856-2:2009 - Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting flue pipes
• Effective Date: 18-Jan-2023
• Revised: SIST EN 1856-2:2009 - Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting flue pipes
• Effective Date: 19-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 1856-2:2021
01-september-2021
Dimovodne naprave - Zahteve za kovinske dimovodne naprave - 2. del: Kovinske
tuljave in povezovalni dimovodi
Chimneys - Requirements for metal chimneys - Part 2: Metal flue liners and connecting
flue pipes
Abgasanlagen - Anforderungen an Metall-Abgasanlagen - Teil 2: Innenrohre und
Verbindungsstücke aus Metall
Conduits de fumée - Prescriptions pour les conduits de fumée métalliques - Partie 2 :
Tubages et éléments de raccordements métalliques
Ta slovenski standard je istoveten z: prEN 1856-2
ICS:
91.060.40 Dimniki, jaški, kanali Chimneys, shafts, ducts
oSIST prEN 1856-2:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 1856-2:2021

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oSIST prEN 1856-2:2021


DRAFT
EUROPEAN STANDARD
prEN 1856-2
NORME EUROPÉENNE

EUROPÄISCHE NORM

May 2021
ICS 91.060.40 Will supersede EN 1856-2:2009
English Version

Chimneys - Requirements for metal chimneys - Part 2:
Metal flue liners and connecting flue pipes
Conduits de fumée - Prescriptions pour les conduits de Abgasanlagen - Anforderungen an Metall-
fumée métalliques - Partie 2 : Tubages et éléments de Abgasanlagen - Teil 2: Innenrohre und
raccordements métalliques Verbindungsstücke aus Metall
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 166.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


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. prEN 1856-2:2021 E
worldwide for CEN national Members.

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oSIST prEN 1856-2:2021
prEN 1856-2:2021 (E)
Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Product characteristics . 6
4.1 Mechanical resistance and stability . 6
4.1.1 Rigid flue liners and their fittings . 6
4.1.2 Flexible flue liners and their fittings . 7
4.1.3 Connecting flue pipes and their fittings . 7
4.2 Reaction to fire . 8
4.3 Resistance to fire . 8
4.3.1 Sootfire resistance classes . 8
4.3.2 Sootfire resistance . 9
4.3.3 Thermal performance under normal working conditions . 9
4.4 Hygiene, health and environment, gas tightness . 10
4.5 Safety in use. 11
4.5.1 Thermal resistance . 11
4.5.2 Condensate resistance . 11
4.5.3 Flow resistance of flue liners and connecting flue pipes . 11
4.6 Durability . 12
4.6.1 Durability against corrosion . 12
4.6.2 Freeze thaw resistance . 16
5 Testing, assessment and sampling methods specific to metal flue liners and
connecting flue pipes . 16
5.1 Measure of diameter of flexible flue liner . 16
5.1.1 Procedure. 16
5.1.2 Results . 16
5.2 Gas tightness . 17
5.2.1 Rigid flue liners and connecting flue pipes . 17
5.2.2 Flexible flue liners . 17
5.3 Additional mechanical tests for flexible liners . 17
5.3.1 General . 17
5.3.2 Tensile strength . 18
5.3.3 Crushing resistance . 18
5.3.4 Flexibility test . 19
5.3.5 Torsion strength test . 20
5.4 Thermal performance test . 21
5.4.1 General . 21
5.4.2 Normal working conditions . 22
5.4.3 Sootfire conditions . 22
5.4.4 Results . 22
5.4.5 Test structures . 22
5.4.6 Test samples . 23
5.5 Condensate resistance . 28
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prEN 1856-2:2021 (E)
5.5.1 General . 28
5.5.2 Condensate penetration (liquid phase) . 28
5.5.3 Condensate resistance (vapour phase) . 28
6 Assessment and verification of constancy of performance – AVCP . 28
6.1 General . 28
6.2 Type testing . 28
6.2.1 General . 28
6.2.2 Test samples, testing and compliance criteria . 29
6.2.3 Test reports . 31
6.2.4 Shared other party results . 31
6.2.5 Cascading determination of the product type results . 32
6.3 Factory production control (FPC) . 33
6.3.1 General . 33
6.3.2 Characteristics . 33
6.3.3 Product specific characteristics . 35
6.3.4 Initial inspection of factory and of FPC . 36
6.3.5 Continuous surveillance of FPC . 36
6.3.6 Procedure for modifications . 37
6.3.7 One-off components, pre-production products (e.g. prototypes) and components
produced in very low quantity . 37
7 Designation and product information . 38
7.1 Designation system . 38
7.2 Other information . 39
8 Marking, labelling and packaging . 39
8.1 Flue gases carrying components . 39
8.2 Chimney plate . 39
Annex ZA (informative) Relationship of this European Standard with Regulation (EU)
No. 305/2011 . 41
ZA.1 Scope and relevant characteristics . 41
ZA.2 System of Assessment and Verification of Constancy of Performance (AVCP) . 44
ZA.3 Assignment of AVCP tasks . 45
Bibliography . 48

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oSIST prEN 1856-2:2021
prEN 1856-2:2021 (E)
European foreword
This document (prEN 1856-2:2021) has been prepared by Technical Committee CEN/TC 166
“Chimneys”, the secretariat of which is held by ASI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 1856-2:2009.
The main changes in comparison to EN 1856-2:2009 are:
— adoption of the template for harmonized standards under the EU Construction Products Regulation
(305/2011/EU) meaning a clearer definition of the Scope, rewording in Clause 4 “Product
characteristics”, Clause 5 “Testing, assessment and sampling methods” and Clause 7 “Product
classification and designation”, and adoption of the template for Clause 6 “Assessment and
verification of constancy of performance”;
— adoption of prEN 1856-1:2021, new revised Annex A “Corrosion tests”. The material table with
minimum material specification of the former edition has been taken over.
This document has been prepared under a standardization request given to CEN by the European
Commission and the European Free Trade Association, and supports essential requirements of EU
Regulation(s).
For relationship with EU Regulation(s), see informative Annex ZA, which is an integral part of this
document.
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oSIST prEN 1856-2:2021
prEN 1856-2:2021 (E)
1 Scope
This document specifies the characteristics of performance for rigid or flexible metal flue liners, rigid
metal connecting flue pipes and their fittings used to convey the products of combustion from appliances
to the outside atmosphere (including their supports) or the chimney.
This document specifies sootfire resistant flue liners, connecting flue pipes and fittings for combustion
appliances burning solid, liquid and gaseous fuels and non-sootfire resistant flue liners, connecting flue
pipes and fittings for combustion appliances burning liquid and gaseous fuels only.
NOTE This means that flue liners, connecting flue pipes and fittings designated “O” are not suitable for
combustion appliances burning solid fuel.
Vitreous enamelled connecting flue pipes are also covered by this document.
Rigid flue liners can be used as flue liners for renovation or adaptation of existing chimneys and as flue
liners of custom built chimneys.
Flexible metal flue liners described in this document are exclusively for renovation or adaptation of
existing chimneys. Flexible connecting flue pipes and extensible flexible products designed to be
compressed or extended along their length are excluded from the scope of this document.
Single-wall and multi-wall system chimney products (chimney sections, chimney fittings and terminals,
including supports) are covered by prEN 1856-1:2021, even if used as liners for existing chimneys or
connecting flue pipes.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 573-3:2013, Aluminium and aluminium alloys - Chemical composition and form of wrought products -
Part 3: Chemical composition and form of products
EN 1443:2019, Chimneys - General requirements
prEN 1856-1:2021, Chimneys - Requirements for metal chimneys - Part 1: System chimney products
EN 10025-2:2019, Hot rolled products of structural steels - Part 2: Technical delivery conditions for non-
alloy structural steels
EN 10088-1:2014, Stainless steels - Part 1: List of stainless steels
EN 10131:2006, Cold rolled uncoated and zinc or zinc-nickel electrolytically coated low carbon and high
yield strength steel flat products for cold forming - Tolerances on dimensions and shape
EN 10209:2013, Cold rolled low carbon steel flat products for vitreous enamelling - Technical delivery
conditions
EN 10346:2015, Continuously hot-dip coated steel flat products for cold forming - Technical delivery
conditions
EN 13216-1:2019, Chimneys - Test methods for system chimneys - Part 1: General test methods
EN 13384-1:2015+A1:2019, Chimneys - Thermal and fluid dynamic calculation methods - Part 1: Chimneys
serving one combustion appliance
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oSIST prEN 1856-2:2021
prEN 1856-2:2021 (E)
EN 13501-1:2018, Fire classification of construction products and building elements - Part 1: Classification
using data from reaction to fire tests
EN 14241-1:2013, Chimneys - Elastomeric seals and elastomeric sealants - Material requirements and test
methods - Part 1: Seals in flue liners
EN 15287-1:2007+A1:2010, Chimneys - Design, installation and commissioning of chimneys - Part 1:
Chimneys for non-roomsealed heating appliances
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1443:2019 and
prEN 1856-1:2021 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
bending radius
minimum radius measured on the inner side of a flexible flue liner when bent
3.2
double skin flexible flue liner
flexible flue liner consisting of two layers of metal, where the inner layer forming the flue is flat and covers
the corrugations
3.3
flue liner kit
flue liner that is installed using a combination of compatible flue liner components, obtained or specified
as a kit from one manufacturing source with product responsibility for the whole flue liner including all
its components
Note 1 to entry: A flue liner kit is not considered a system chimney.
4 Product characteristics
4.1 Mechanical resistance and stability
4.1.1 Rigid flue liners and their fittings
4.1.1.1 Compressive strength
4.1.1.1.1 Sections and fittings
The compressive strength of sections and their fittings shall be tested according to the test method
described in prEN 1856-1:2021, 5.2.1, and shall be expressed in kg of chimney or preferably equivalent
meters of sections length.
4.1.1.1.2 Liner supports
The compressive strength of liner supports shall be tested according to the test method described in
prEN 1856-1:2021, 5.2.2, and shall be expressed in kg of liner or preferably equivalent meters of sections
length.
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oSIST prEN 1856-2:2021
prEN 1856-2:2021 (E)
4.1.1.2 Tensile strength
The tensile strength of liners and their fittings shall be tested according to the test method described in
prEN 1856-1:2021, 5.3, and shall be expressed in kg of liner or preferably equivalent meters of sections
length.
4.1.1.3 Non-vertical installation
The non-vertical installation shall be tested according to the test method described in prEN 1856-1:2021,
5.4.1, and expressed as maximum length between the supports.
4.1.2 Flexible flue liners and their fittings
4.1.2.1 General
Flexible flue liners and their fittings shall comply with the characteristics of 4.1.2.2 to 4.1.2.4.
4.1.2.2 Compressive strength of fittings and supports
The compressive strength of fittings and supports shall be tested according to the test method described
in prEN 1856-1:2021, 5.2.1 and 5.2.2, and shall be expressed in kg of liner or preferably equivalent meters
of sections length.
4.1.2.3 Compressive strength of flexible flue liners
The compressive strength of flexible flue liners is tested as crushing resistance and shall be tested in
accordance with 5.3.3; the outside diameter of the flexible flue liner shall not have been reduced to less
than 75 % of its original nominal diameter and shall fulfil the gas tightness requirement of 4.4.
4.1.2.4 Tensile strength
4.1.2.4.1 General
The tensile strength of the flexible flue liner and fittings and shall be tested according to the test method
described in 5.3.2 and shall be expressed in kg of liner and preferably equivalent meters of length.
After the test, the flexible flue liner shall meet the gas tightness requirement described in 4.4.
In addition, tensile strength in relation to flexibility and torsion shall fulfil 4.1.2.4.2 and 4.1.2.4.3.
4.1.2.4.2 Flexibility
The flexibility of the flexible flue liner shall be tested according to the test method described in 5.3.4 and
expressed as minimum declared bending radius.
After the test, the flexible flue liner shall fulfil the gas tightness requirement of 4.4 and the inner layer of
the double skin flexible flue liner shall remain overlapped.
Oval flexible liners shall be subjected to the test method of 5.3.4 in both axes of the oval shape.
4.1.2.4.3 Torsion strength
The torsion strength of flexible liners shall be tested according to the test method described in 5.3.5.
After the test, the flexible flue liner shall meet the gas tightness requirement described in 4.4.
4.1.3 Connecting flue pipes and their fittings
4.1.3.1 General
Connecting flue pipes and their fittings shall comply with the characteristics of 4.1.3.2 to 4.1.3.4.
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prEN 1856-2:2021 (E)
4.1.3.2 Compressive strength
4.1.3.2.1 Sections and fittings
The compressive strength of sections and their fittings shall be tested according to the test method
described in prEN 1856-1:2021, 5.2.1, and shall be expressed in kg of connecting flue pipe or preferably
equivalent meters of sections length.
4.1.3.2.2 Connecting flue pipe supports
The compressive strength of connecting flue pipe supports shall be tested according to the test method
described in prEN 1856-1:2021, 5.2.2, and shall be expressed in kg of connecting flue pipe or preferably
equivalent meters of sections length.
4.1.3.3 Tensile strength
The tensile strength of connecting flue pipes and their fittings shall be tested according to the test method
described in prEN 1856-1:2021, 5.3, and shall be expressed in kg of connecting flue pipe or preferably
equivalent meters of sections length.
4.1.3.4 Non-vertical installation
The non-vertical installation of connecting flue pipes and their fittings shall be tested according to the
test method described in prEN 1856-1:2021, 5.4.1, and expressed as maximum length between the
supports.
4.2 Reaction to fire
The reaction to fire shall be declared. Classification may be carried out via testing according to the
relevant product standard and in accordance with EN 13501-1:2018.
Metal flue liners and connecting flue pipes shall be classified A1 without testing.
NOTE More information is available in Commission Decision [96/603/EC (2)].
Classification of other materials, i.e. thermal insulation, plastic air supply duct, shall be assessed via
testing according to the relevant product standard and in accordance with EN 13501-1:2018.
4.3 Resistance to fire
4.3.1 Sootfire resistance classes
The sootfire resistance class of the flue liner or connecting flue pipe shall be declared.
Sootfire resistance classes are:
— O for chimneys, flue liners, connecting flue pipes, components and accessories without sootfire
resistance;
— G for chimneys, flue liners, connecting flue pipes, components and accessories with sootfire
resistance.
The sootfire resistance class shall be expressed as G or O as described above.
Additionally, for connecting flue pipes, the letter G or O shall be followed by the distance to combustible
materials (xx) expressed in mm, followed by (M) or (NM).
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4.3.2 Sootfire resistance
4.3.2.1 Rigid flue liners and their fittings
The sootfire resistance of rigid flue liners and their fittings shall be tested according to the test method
described in 5.4, with the test structure defined in 5.4.5.1 and the test sample in 5.4.6.2, and shall be
expressed as described in 4.3.1.
The gas tightness according to 4.4 shall be met before and after the sootfire resistance test.
4.3.2.2 Flexible flue liners and their fittings
The sootfire resistance of flexible flue liners and their fittings shall be tested according to the test method
described in 5.4, with the test structure defined in 5.4.5.1 and the test sample in 5.4.6.1, and shall be
expressed as described in 4.3.1.
The gas tightness according to 4.4 shall be met before and after the sootfire resistance test.
The test sample shall allow the test ball defined in 5.4.6.1.2 to move freely down.
4.3.2.3 Connecting flue pipes and their fittings
The sootfire resistance of connecting flue pipes and their fittings shall be tested according to the test
method described in 5.4, with the test structure defined in 5.4.5.2 and the test sample in 5.4.6.3, and shall
be expressed as described in 4.3.1.
The gas tightness according to 4.5 shall be met before and after the sootfire resistance test.
The minimum distance to combustible material shall be declared, either measured (M) according to 5.4
– the preferred method - or calculated (NM) as at least three times their nominal diameter but not less
rd
than 375 mm (as specified in EN 15287-1:2007+A1:2010, 4.3.9.3, 3 paragraph, first sentence for
connecting flue pipes naturally ventilated) and the characteristics of 4.3.3 shall be met.
4.3.3 Thermal performance under normal working conditions
4.3.3.1 General
The thermal performance under normal working conditions, performed for G and O designated flue liners
and connecting flue pipes, shall be tested according to the test method described in 5.4 and shall be
expressed as described in 4.3.1, with the addition of the temperature class according to Table 1.
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Table 1 — Temperature classes and test temperatures
Nominal working Flue gas test
temperature (t) temperature
Temperature class
°C °C
T 080 t ≤ 80 100
T 100 t ≤ 100 120
T 120 t ≤ 120 150
T 140 t ≤ 140 170
T 160 t ≤ 160 190
T 200 t ≤ 200 250
T 250 t ≤ 250 300
T 300 t ≤ 300 350
T 400 t ≤ 400 500
T 450 t ≤ 450 550
T 600 t ≤ 600 700
4.3.3.2 Rigid flue liners and their fittings
The thermal performance under normal working conditions of rigid flue liners and their fittings shall be
tested according to the test method described in 5.4, with the test structure defined in 5.4.5.1 and the test
sample in 5.4.6.2.
The gas tightness according to 4.4 shall be met.
4.3.3.3 Flexible flue liners and their fittin
...