ISO 23551-6:2014

Safety and control devices for gas burners and gas-burning appliances — Particular requirements — Part 6: Thermoelectric flame supervision controls

ISO 23551-6:2014 specifies safety, constructional, and performance requirements for thermoelectric flame supervision controls, energized by a thermocouple, intended for use with gas burners and gas-burning appliances, hereafter referred to as "controls". ISO 23551-6:2014 applies to thermoelectric flame supervision controls for gas burners and gas-burning appliances of nominal connection size up to, and including DN 50, that can be used and tested independently of these appliances. These thermoelectric flame supervision controls are suitable for fuel gases, such as natural gas, manufactured gas, or liquefied petroleum gas (LPG) at inlet pressures up to and including 50 kPa. ISO 23551-6:2014 covers type testing only. It is neither applicable to the thermocouple nor to controls which use auxiliary energy (e.g. electrical energy supplied externally).

Dispositifs de commande et de sécurité pour brûleurs à gaz et appareils à gaz — Exigences particulières — Partie 6: Équipements thermoélectriques de surveillance de flamme

General Information

• Status: Withdrawn
• Publication Date: 05-Aug-2014
• Withdrawal Date: 05-Aug-2014
• ICS: 27.060.20 - Gas fuel burners
• Technical Committee: ISO/TC 161 - Controls and protective devices for gas and/or oil
• Drafting Committee: ISO/TC 161 - Controls and protective devices for gas and/or oil
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 01-Nov-2021

Relations

• Revised: ISO 23551-6:2021 - Safety and control devices for gas burners and gas-burning appliances — Particular requirements — Part 6: Thermoelectric flame supervision controls
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 23551-6
First edition
2014-08-15
Safety and control devices for gas
burners and gas-burning appliances —
Particular requirements —
Part 6:
Thermoelectric flame supervision
controls
Dispositifs de commande et de sécurité pour brûleurs à gaz et
appareils à gaz — Exigences particulières —
Partie 6: Équipements thermoélectriques de surveillance de flamme
Reference number
ISO 23551-6:2014(E)
©
ISO 2014

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ISO 23551-6:2014(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
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Published in Switzerland
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ISO 23551-6:2014(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification . 2
4.1 Classes of controls . 2
4.2 Groups of controls . 2
5 Test conditions . 2
6 Construction . 2
6.1 General . 2
6.2 Construction requirements . 3
6.3 Materials . 3
6.4 Gas connections . 4
7 Performance . 5
7.1 General . 5
7.2 Leak-tightness. 5
7.3 Torsion and bending . 6
7.4 Rated flow rate . 6
7.5 Durability . 6
7.6 Functional requirements . 6
7.7 Endurance . 8
8 EMC/electrical requirements . 9
9 Marking, installation, and operating instructions . 9
9.1 Marking . 9
9.2 Installation and operating instructions . 9
9.3 Warning notice .10
Annex A (informative) Leak-tightness test — Volumetric method .11
Annex B (informative) Leak-tightness test — Pressure-loss method .12
Annex C (normative) Conversion of pressure loss into leakage rate .13
Annex D (normative) Test for immunity to power-frequency magnetic fields.14
Annex E (normative) Specific regional requirements in European countries .15
Annex F (normative) Specific regional requirements in Canada and USA .16
Annex G (normative) Specific regional requirements in Japan .17
Annex H (informative) Types of flame supervision controls .18
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ISO 23551-6:2014(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 on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 161, Control and protective devices for gas and/or
oil burners and appliances.
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ISO 23551-6:2014(E)

Introduction
This part of ISO 23551 is designed to be used in combination with ISO 23550. This part, together with
ISO 23550, establishes the full requirements as they apply to the product covered by this International
Standard. This part adapts ISO 23550, where needed, by stating “with the following modification”, “with
the following addition”, “is replaced by the following”, or “is not applicable”, in the corresponding clause.
In order to identify specific requirements that are particular to this part, that are not already covered
by ISO 23550, this International Standard might contain clauses or subclauses that are additional to the
structure of ISO 23550. These clauses are numbered starting from 101 or, in the case of an Annex, are
designated AA, BB, CC etc.
In an attempt to develop a fully International Standard, it has been necessary to take into consideration
the differing requirements resulting from practical experience and installation practices in various
regions of the world and to recognize the variation in basic infrastructure associated with gas and/or
oil controls and appliances, some of which are addressed in Annexes E, F, and G. This International
Standard intends to provide a basic framework of requirements that recognize these differences.
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INTERNATIONAL STANDARD ISO 23551-6:2014(E)
Safety and control devices for gas burners and gas-burning
appliances — Particular requirements —
Part 6:
Thermoelectric flame supervision controls
1 Scope
This part of ISO 23551 specifies safety, constructional, and performance requirements for thermoelectric
flame supervision controls, energized by a thermocouple, intended for use with gas burners and gas-
burning appliances, hereafter referred to as “controls”.
This part of ISO 23551 applies to thermoelectric flame supervision controls for gas burners and gas-
burning appliances of nominal connection size up to, and including DN 50, that can be used and tested
independently of these appliances.
These thermoelectric flame supervision controls are suitable for fuel gases, such as natural gas,
manufactured gas, or liquefied petroleum gas (LPG) at inlet pressures up to and including 50 kPa.
This International Standard covers type testing only.
This International Standard is not applicable to
a) the thermocouple and
b) controls which use auxiliary energy (e.g. electrical energy supplied externally).
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 23550:2011, Safety and control devices for gas burners and gas-burning appliances — General
requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 23550 and the following apply.
3.101
thermocouple
thermoelectric flame sensing element that responds to the temperature of the supervised flame,
resulting in an electromotive force (e.m.f.)
3.102
thermoelectric flame supervision control
control which, in response to the e.m.f. produced by the thermocouple, maintains the gas way to the main
burner; or the main burner and the pilot burner open and which shuts off the gas way after extinction
of the supervised flame
Note 1 to entry: For example, see Figure AA.1.
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ISO 23551-6:2014(E)

3.103
ignition interlock
part which prevents the igniter from operating as long as the main gas way is open
3.104
re-start interlock
mechanism which prevents the re-opening of the gas way to the main burner or to the main burner and
the pilot burner until the armature plate has separated from the magnetic element
Note 1 to entry: For further reference, see Figure AA.1.
3.105
sealing force
force acting on the closure member when the closure member is in the closed position, independent of
any force provided by fuel gas pressure
3.106
closed position
position of the closure member(s) in the absence of the thermoelectric energy
4 Classification
4.1 Classes of controls
ISO 23550:2011, 4.1 is replaced by the following:
Controls are classified according to the number of operations:
— 5 000 operations (e.g. central heating);
— 6 000 operations;
— 10 000 operations (e.g. space heaters);
— 40 000 operations (e.g. domestic cooking).
NOTE Specific regional requirements are given in Annexes F and G.
4.2 Groups of controls
Shall be according to ISO 23550:2011, 4.2.
NOTE Specific regional requirements are given in Annexes F and G.
5 Test conditions
Shall be according to ISO 23550:2011, Clause 5.
6 Construction
6.1 General
Shall be according to ISO 23550:2011, 6.1, with the following addition:
— Controls shall also be designed, so that during ignition, either the gas way to the main burner is
open, if there is no pilot burner; or the gas way to the main burner is closed and that to the pilot
burner is open.
— Controls shall also be designed so that the sealing force is not decreased by the gas inlet pressure.
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ISO 23551-6:2014(E)

6.2 Construction requirements
6.2.1 Appearance
Shall be according to ISO 23550:2011, 6.2.1.
6.2.2 Holes
Shall be according to ISO 23550:2011, 6.2.2.
6.2.3 Breather holes
ISO 23550:2011, 6.2.3 is not applicable.
6.2.4 Screwed fastenings
Shall be according to ISO 23550:2011, 6.2.4.
6.2.5 Jointing
Shall be according to ISO 23550:2011, 6.2.5.
6.2.6 Moving parts
Shall be according to ISO 23550:2011, 6.2.6.
6.2.7 Sealing caps
Shall be according to ISO 23550:2011, 6.2.7.
6.2.8 Dismantling and reassembling for servicing and/or adjustment
Shall be according to ISO 23550:2011, 6.2.8.
6.2.9 Auxiliary channels
Shall be according to ISO 23550:2011, 6.2.9.
6.3 Materials
6.3.1 General material requirements
Shall be according to ISO 23550:2011, 6.3.1.
6.3.2 Housing
6.3.2.1 Housing design
Shall be according to ISO 23550:2011, 6.3.2.1.
6.3.2.2 Test for leakage of housing after removal of non-metallic parts
Shall be according to ISO 23550:2011, 6.3.2.2
...