EN 126:2012/prA1

Multifunctional controls for gas burning appliances

This amendment specifies requirements for gas shut-off function.

Mehrfachstellgeräte für Gasgeräte

Equipments multifonctionnels pour les appareils à gaz

Večnamenske naprave za nadzor plinskih aparatov

General Information

• Status: Not Published
• Publication Date: 04-Sep-2016
• Withdrawal Date: 05-Mar-2017
• ICS: 23.060.40 - Pressure regulators
• Technical Committee: CEN/TC 58 - Safety and control devices for burners and appliances burning gaseous or liquid fuels
• Drafting Committee: CEN/TC 58/WG 11 - Generics
• Current Stage: 4598 - Decision to abandon - Finalization for Vote
• Start Date: 10-Mar-2017
• Completion Date: 14-Apr-2025
• Directive: 2009/142/EC - DIRECTIVE 2009/142/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 30 November 2009 relating to appliances burning gaseous fuels
• Mandate: M/BC/CEN/89/6 - Standardization request to CEN concerning appliances burning gaseous fuels
• Ref Project: SIST EN 126:2012/oprA1:2015 - Multifunctional controls for gas burning appliances

Relations

• Amends: EN 126:2012 - Multifunctional controls for gas burning appliances
• Effective Date: 12-Jun-2013

Overview

EN 126:2012/prA1 is an amendment to EN 126:2012 published by CEN that clarifies and extends requirements for the gas shut-off function in multifunctional controls for gas-burning appliances. Its purpose is to define assessment methods, construction and performance requirements, and additional measures needed when new electromechanical solutions are used to achieve a safety class C shut-off function.

This amendment introduces a normative Annex BB "Gas shut-off function" and an informative Annex CC with examples. It emphasises the role of Stored Closing Energy (SCE) and specifies required declarations and tests manufacturers must provide.

Key Topics

• Safety class C requirement: The gas shut-off function shall meet safety class C to protect against uncontrolled gas flow, fire and explosion.
• Two-valve principle: Two shut-off valves are required to ensure shut-off in case one valve fails. A single shut-off valve solution is not acceptable for safety class C.
• Stored Closing Energy (SCE): Defined as energy available after power interruption to move and keep the closure member closed. Manufacturers must declare the type of SCE used.
• Permitted valve combinations (Annex BB):
  • Two automatic shut-off valves: acceptable without additional measures.
  • Automatic + valve with SCE: acceptable; electronic SCE circuit must be included in fault assessment.
  • Automatic + valve without SCE: allowed only for non-permanent operations and requires additional measures.
  • Two valves without SCE: not acceptable.
• Additional safety measures for valves without SCE or with electrical SCE:
  • Functional leakage check at each burner cycle for valves without SCE (maximum leakage 1 l/h).
  • Electrical integrity test of the actuator each burner cycle; failure must lead to safety shut-down and non-volatile lock-out.
  • Closing torque/force must be at least 2.5× the friction torque/force.
  • Sealing force tests with actuator de-energized at 85% of minimum rated mains voltage and under worst-case conditions.
• Fault assessment and new technologies: New electromechanical solutions must be supported by a failure mode analysis and fault assessment (BB.6) addressing closing at power interruption, leak tightness, sealing force, independent action of valves, and fault reaction time.

Applications

This amendment is targeted at manufacturers, test laboratories and compliance engineers designing or evaluating multifunctional control systems for gas burners and appliances. It provides:

• Guidance to assess new valve/actuator technologies and electronic SCE solutions.
• Test criteria and declaration requirements to demonstrate compliance with safety class C.
• Practical measures to maintain availability and safe shut-off during power interruptions.

Related Standards

• EN 161 (sealing force and backpressure requirements)
• EN 13611 (performance and endurance tests referenced by BB.5 and BB.7)
• EN 14459 (fault assessment methodology referenced by BB.6)

Manufacturer declarations required: type of SCE, valve combination, sealing force and closing time (per EN 161), and fault reaction time. These declarations support conformity assessment and safe integration into gas appliance systems.

Standards Content (Sample)

SLOVENSKI STANDARD
01-februar-2015
9HþQDPHQVNHQDSUDYH]DQDG]RUSOLQVNLKDSDUDWRY
Multifunctional controls for gas burning appliances
Mehrfachstellgeräte für Gasgeräte
Equipments multifonctionnels pour les appareils à gaz
Ta slovenski standard je istoveten z: EN 126:2012/prA1
ICS:
23.060.99 Drugi ventili Other valves
27.060.20 Plinski gorilniki Gas fuel burners
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
DRAFT
EN 126:2012
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
November 2014
ICS 23.060.40
English Version
Multifunctional controls for gas burning appliances
Equipments multifonctionnels pour les appareils à gaz Mehrfachstellgeräte für Gasgeräte
This draft amendment is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 58.

This draft amendment A1, if approved, will modify the European Standard EN 126:2012. If this draft becomes an amendment, CEN
members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of this amendment
into the relevant national standard without any alteration.

This draft amendment 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, 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: Avenue Marnix 17, B-1000 Brussels
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 126:2012/prA1:2014 E
worldwide for CEN national Members.

Contents
Page
Foreword .3
Annex BB (normative) Gas shut-off function .5
BB.1 Introduction .5
BB.2 Classification .6
BB.3 Construction requirements .6
BB.3.1 General .6
BB.3.2 Valve combinations .7
BB.3.3 Two automatic shut-off valves .7
BB.3.4 One automatic shut-off and one shut-off valve with SCE .7
BB.3.5 One automatic shut-off and one shut-off valve without SCE .7
BB.3.6 Two shut-off valves with SCE .7
BB.3.7 One shut-off with SCE and one shut-off valve without SCE .7
BB.3.8 Two shut-off valves without SCE .7
BB.4 Additional safety measures .7
BB.4.1 General .7
BB.4.2 Functional check (internal leakage, for systems with no SCE only) .7
BB.4.3 Electrical integrity of the actuator of the valve .8
BB.4.4 Closing torque or force of the actuator .8
BB.4.5 Sealing force test .8
BB.5 Performance requirements .8
BB.6 Protection against internal faults for the purpose of functional safety .8
BB.7 Long-term performance test .9
BB.8 EMC/Electrical requirements .9
BB.9 Marking, installation, operating instructions and declarations .9
Annex CC (informative) Examples of new solutions . 10
CC.1 Example . 10
CC.1.1 Description . 10
CC.1.2 Rationale . 10
CC.2 Example 2 . 11
CC.2.1 Description . 11
CC.2.2 Rationale . 11
CC.3 Example 3 . 11
CC.3.1 Description . 11
CC.3.2 Comparison between existing solution (EN 126) with a substitution of an automatic shut-off
valve by a motorized valve . 11

Foreword
This document (EN 126:2012/prA1:2014) has been prepared by Technical Committee CEN/TC 58 “Safety and
control devices for burners and appliances burning gaseous or liquid fuels”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This Amendment (see Annex BB) is supposed to replace EN 14459:2007, Annex L “Gas shut-off function”. In
addition to that EN 126:2012, Clause 3 and Clause 6 are modified accordingly.
Introduce the following three modifications to EN 126:2012:

1) Add the following after 3.106:

3.107
stored closing energy
SCE
energy available (even after interruption of the power supply) to move the closure member into the closed position
and keep it closed
3.108
shut-off valve
valve that opens and closes the gas flow other than automatic shut-off valves

2) Replace the text under 6.103.2 by the following:

Shall be according to Annex BB.

3) Introduction of the following normative Annex BB “Gas shut-off function” and the informative
Annex CC “Examples of new solutions” after the last Annex AA.
Annex BB
(normative)
Gas shut-off function
BB.1 Introduction
This Annex defines a method for assessing solutions for the gas shut-off function as well as requirements for
solutions other than those described in this document for use in gas appliances. In this document, the term safety
class A, class B and class C is not related to the sealing force classes. The sealing force shall be indicated in the
backpressure value as defined in EN 161 and as required in the relevant gas appliance standard. Those
requirements shall not be superseded by this annex.
Protection against fire and explosion in a gas appliance, as a result of uncontrolled gas flow, requires a safety
class C system for the gas shut-off function. This is based on a comparison, made between an automatic burner
controller and gas shut-off function, the safety class of each considered equal.
Today’s solutions (see Figure BB.1) according to this document, using two automatic shut-off valves, fulfil the
safety class C requirement even though they are not based on a fault assessment approach as specified in
EN 14459:2007, 6.6. This assumption is based on specific mechanical solutions originating from practice over
many years and as a principle relying on redundancy of two automatic shut-off valves, fulfilling the construction and
performance requirements of this document.

Key
1 burner control (BC)
Figure BB.1 — Standard solution with two valves
The approach of the above mentioned classifications can be used as a reference for assessing new solutions.
A safety class C shut-off function with only one shut-off valve is not acceptable.
New solutions of the gas shut-off function may consist of a combination of shut-off valves, electronic controller,
sensing elements, actuators, lock-out and reset as shown in Figure BB.2.
Key
1 automatic burner control (BC) 5 electronic controller for gas shut-off function
2 on/off 6 sensor
3 lockout 7 actuator
4 reset 8 mains supply
Figure BB.2 — Example of components in a new solution
BB.2 Classification
The gas shut-off function shall be safety class C.
BB.3 Construction requirements
BB.3.1 General
The constructional requirements are given in EN 14459:2007, Clause 6.
The sealing force and the closing time of the shut off valves shall be according to EN 161. The manufacturer shall
declare the type of Stored Energy (SCE), the sealin
...