ISO 23551-5:2014

Safety and control devices for gas burners and gas-burning appliances - Particular requirements - Part 5: Manual gas valves

ISO 23551-5:2014 specifies safety, constructional and performance requirements for manual gas valves intended for use with gas burners and gas-burning appliances, hereafter referred to as ?valves', unless otherwise specified. ISO 23551-5:2014 applies to following types of manual gas valves: manual gas shut-off valve; gas burner valve; appliance connector valve; "delta C" valve. ISO 23551-5:2014 applies to valves for gas burners and gas-burning appliances of nominal connection size up to and including DN 100 that can be used and tested independently of these appliances using fuel gases, as natural gas, manufactured gas or liquefied petroleum gas (LPG) at inlet pressures up to and including 500 kPa. It is not applicable to corrosive and waste gases. ISO 23551-5:2014 covers type testing only.

Dispositifs de commande et de sécurité pour brûleurs à gaz et appareils à gaz — Exigences particulières — Partie 5: Robinets de gaz manuels

General Information

• Status: Withdrawn
• Publication Date: 07-May-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
• Start Date: 18-Oct-2023
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO 23551-5:2023 - Safety and control devices for gas burners and gas-burning appliances - Particular requirements - Part 5: Manual gas valves
• Effective Date: 02-Jun-2018

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 23551-5
First edition
2014-05-01
Safety and control devices for gas
burners and gas-burning appliances —
Particular requirements —
Part 5:
Manual gas valves
Dispositifs de commande et de sécurité pour brûleurs à gaz et
appareils à gaz — Exigences particulières —
Partie 5: Robinets de gaz manuels
Reference number
©
ISO 2014
© 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
the requester.
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Published in Switzerland
ii © ISO 2014 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classes of control. 2
4.1 Classes of controls . 2
4.2 Groups of controls . 3
5 Test conditions . 3
6 Construction . 3
6.1 General . 3
6.2 Construction requirements . 3
6.3 Materials . 4
6.4 Gas connections . 5
6.102 Appliance connector valves . 7
7 Performance . 8
7.1 General . 8
7.2 Leak-tightness. 8
7.3 Torsion and bending . 8
7.4 Rated flow rate . 8
7.5 Durability . 9
7.6 Functional requirements: Operating torque and force . 9
7.7 Endurance .13
8 EMC/Electrical requirements .15
9 Marking, installation and operating instructions .15
9.1 Marking .15
9.2 Installation and operating instructions .16
9.3 Warning notice .17
Annex A (informative) Leak-tightness test — Volumetric method .18
Annex B (informative) Leak-tightness test — Pressure-loss method .19
Annex C (normative) Conversion of pressure loss into leakage rate .20
Annex D (normative) Test for immunity to power-frequency magnetic fields.21
Annex E (normative) Specific regional requirements in European countries .22
Annex F (normative) Specific regional requirements in Canada and USA .23
Annex G (normative) Specific regional requirements in Japan .25
Annex AA (informative) Examples of manual gas shut-off valves.26
Bibliography .33
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. 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. 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 oil
burners and gas and oil burning appliances.
ISO 23551 consists of the following parts, under the general title Safety and control devices for gas burners
and gas-burning appliances — Particular requirements:
— Part 1: Automatic and semi-automatic valves
— Part 2: Pressure regulators
— Part 3: Gas/air ratio controls, pneumatic type
— Part 4: Valve-proving systems for automatic shut-off valves
— Part 5: Manual gas valves
— Part 6: Thermoelectric flame supervision controls
iv © ISO 2014 – All rights reserved

Introduction
This part of ISO 23551 is designed to be used in combination with ISO 23550. This part of ISO 23551
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 document may contain Clauses or Sub-clauses 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 full 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.
INTERNATIONAL STANDARD ISO 23551-5:2014(E)
Safety and control devices for gas burners and gas-burning
appliances — Particular requirements —
Part 5:
Manual gas valves
1 Scope
This part of ISO 23551 specifies safety, constructional and performance requirements for manual gas
valves intended for use with gas burners and gas-burning appliances, hereafter referred to as ‘valves’,
unless otherwise specified.
This International Standard applies to following types of manual gas valves:
— manual gas shut-off valve;
— gas burner valve;
— appliance connector valve;
— “delta C” valve.
This part of ISO 23551 applies to valves for gas burners and gas-burning appliances of nominal connection
size up to and including DN 100 that can be used and tested independently of these appliances using fuel
gases, as natural gas, manufactured gas or liquefied petroleum gas (LPG) at inlet pressures up to and
including 500 kPa. It is not applicable to corrosive and waste gases.
This International Standard covers type testing only.
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 purpose of this document, the terms and definitions given in ISO 23550 and the following apply.
3.101
manual gas shut-off valve
manually operated valve for the control of the gas flow from an “off” to an “on” position and vice versa
Note 1 to entry: Parts commonly used in manual gas shut-off valves are shown as examples in Figures AA.1 to
AA.5.
3.102
“delta C” valve
manual gas valve suitable for use on food service equipment (commercial cooking equipment)
Note 1 to entry: These valves are identified by a “delta C” marking.
3.103
gas burner valve
manual gas valve that requires user initiation of each usage cycle
Note 1 to entry: This type of manual gas valve is intended to be used in Canada and the US between the gas supply
piping and the gas burner.
Note 2 to entry: The valve is turned on when the burner operating cycle is initiated and turned off when the
burner operating cycle is completed.
3.104
appliance connector valve
manual gas valve having a non-displaceable valve member, a minimum specified capacity and an internal
taper pipe thread inlet and an outlet for flared tubing connection
Note 1 to entry: This type of manual gas valve is intended to be used in Canada and the US between the gas supply
piping and the appliance connector attached to the appliance.
Note 2 to entry: For minimum capacity see Table 2 and for inlet and outlet connection see 6.102.
3.105
flow rate curve
curve which indicates the air flow in relation to the angle of opening
3.106
bearing seal
shortest distance between gas-carrying parts and the atmosphere measured along the length of the
sealing surfaces
3.107
plug
tapered valve member of a manual gas valve containing one or more gas flow openings
3.108
non-displaceable valve member
valve member that cannot be moved from its seat by a force applied to the handle, or force applied by a
plane surface to any exterior portion of the valve
3.109
safety lock
means in a manual valve that requires a separate action of the user before being able to open the valve
EXAMPLE Pushing on the valve handle to “unlatch” the valve before the valve handle can be rotated to turn
on the gas.
Note 1 to entry: A safety lock is also known as “niting arrangement”.
4 Classes of control
4.1 Classes of controls
Shall be according to ISO 23550:2011, 4.1 with the following addition:
Manual gas valves are classified according to the number of operations:
— 1 000 operations (e.g. appliance connector valves);
— 5 000 operations (e.g. central heating);
— 10 000 operations (e.g. space heaters);
— 12 000 operations; and
2 © ISO 2014 – All rights reserved

— 40 000 operations (e.g. domestic cooking).
NOTE Number of operations during the expected life of the appliance.
4.2 Groups of controls
Shall be according to ISO 23550:2011, 4.2.
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.
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.
6.2.101 Operating parts of manual gas valves
Manual gas valves operated by rotation shall be opened by turning the operating device anticlockwise
and closed by turning it clockwise, except for valves, which provide more than one burner with gas.
Alternate construction is acceptable provided the rotation direction is clearly marked or specified in
the operations and in installation instructions. Manual gas valves with 90° rotation do not have to meet
these requirements when the construction is such that the lever or tee handle is 90° to the line of flow
in the off position and parallel to the line of flow in the on position.
A separable handle, removable without further disassembly of the valve, shall be attached by tamper-
resistant means unless removal of the handle does not affect the leak tightness of the valve or the
retention of the valve member.
Manual gas shut-off valves shall be operated without the use of tools.
It shall not be possible to exert direct axial pressure (other than spring pressure) on the closure member
when the operating spindle is depressed to clear any safety lock.
6.2.102 Seating force
Manual gas valves shall be provided with a means, other than gravity, to maintain a continuous seating
force to compensate for manufacturing tolerances, operational variations, or displacement of lubricant(s).
It shall not be possible in normal use to apply such forces to the closure member that it is lifted out of its
seat or is brought into a position which causes the leakage rates to exceed the values given in 7.2.
6.2.103 Tapered plug cavity
For taper plug manual gas valves the closure member included angle shall be at least 9° 25′. The taper
plug at the large diameter shall be recessed into the body, and the plug shall protrude beyond the taper
of the body at the small end. There shall be adequate clearance provided for this protrusion.
NOTE Regional specific requirements are given in Annex F.
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 with the following modification.
Item b) is not applicable. O-rings, gaskets and other seals are exempt.
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.
6.3.2.101 Manual gas valves with shaft seal
For manual gas valves with shaft seals, the shaft seal is excluded from the requirement in 6.3.2.1, if the
following requirements are met:
4 © ISO 2014 – All rights reserved

The structure surrounding a shaft seal shall be such as to confine the seal properly and, with the seal
removed and the valve in any position, to allow, when tested at room temperature with air, not more
than 45,6 dm /h at a pressure of 1,74 kPa to leak past the shaft.
6.3.3 Springs
Shall be according to ISO 23550:2011, 6.3.3.
6.3.4 Resistance to corrosion and surface protection
Shall be according to ISO 23550:2011, 6.3.4.
6.3.5 Impregnation
Shall be according to ISO 23550:2011, 6.3.5.
6.3.6 Seals for glands for moving parts
Shall be according to ISO 23550:2011, 6.3.6.
6.3.101 Valve closure member
Gas-closing parts shall either have a metallic support to withstand the sealing force or shall be made of
metal. This requirement also applies to parts transmitting the closing force.
For guide elements (see Figures AA.1 to AA.5) non-metallic materials are admissible.
6.4 Gas connections
Shall be according to ISO 23550:2011, 6.4.
6.101 Component parts
6.101.1 General
The off-position shall have a non-adjustable stop.
6.101.2 Turning angles
6.101.2.1 General
The reduced flow position, if any, shall be placed either after the fully open position or between the open
and the closed position.
The turning angle of the manual gas needle valve between the closed and the fully open position shall
be between 180° and 360° when used as a shut-off valve unless otherwise specified in the installation
and operating instructions.
6.101.2.2 Opening at maximum flow
If the reduced flow rate position is placed after the fully open position the following requirements shall
be met:
— in order to change from the closed position to the fully open position the turning angle shall be
(90 ± 5)° unless otherwise specified in the installation and operating instructions;
— the turning angle between the fully open position and the reduced flow rate position shall be greater
than 70° unless otherwise specified in the manufacturer’s installation and operating instructions;
this requirement is not applicable to multi-outlet valves;
— the movement of the manual gas valve closure member shall be limited by a fixed stop at the reduced
flow rate position.
6.101.2.3 Opening at minimum flow
If the reduced flow rate position is placed between the closed and fully open position the following
requirements shall be met:
— in order to change from the closed position to the fully open position the turning angle shall be
greater than 90° unless otherwise specified in the installation and operating instructions;
— in order to change from the reduced flow rate position to the fully open position the turning angle
shall be greater than 70° unless otherwise specified in the installation and operating instructions;
this requirement is not applicable for multi-outlet-valves;
— a reduced flow rate position shall be provided by means of a part which locates the valve closure
member in this position when the movement is in the direction of closing;
— the movement of the manual gas valve closure member shall be limited in the fully open position by
a stop.
6.101.2.4 Single outlet manual gas valves
If a single outlet manual gas valve does not have a reduced flow position, the turning angle to pass
from the closed position to the fully open position shall be (90 ± 5)° unless otherwise specified in the
installation and operating instructions.
6.101.3 Lubrication
A manual gas valve shall be designed so that lubrication, if used, does not cause blockage of any gas way.
6.101.4 Stops
The travel to and from the extreme positions of a manual gas valve shall be limited by stops.
When operating a manual gas needle valve it shall not be possible to remove the needle completely from
the body by unscrewing. When closing the positive stop is obtained by contact of the needle on its seat.
6.101.5 Safety lock
Single outlet manual gas valves may be provided with a safety lock that prevents any accidental opening
as it requires two separate actions to operate the valve. It shall permit ready operation with one hand.
Manual gas valves with two outlets for two separate burners shall be designed so that in order to change
from one outlet to the other it is necessary to pass through a locked closed position. It shall only be
possible for the user to change from one outlet to the other by a deliberate action. In particular it shall
not be possible to change from one outlet to the other by keeping the handle constantly pressed in or by
a pure turning movement.
6.101.6 Bearing seal
The bearing seal for manual gas valves except needle valves shall be at least 3 mm (see Figure AA.1,
Item 9), unless otherwise specified by the manufacturer based on tolerance calculation.
6 © ISO 2014 – All rights reserved

6.101.7 Pre-setting devices
If present, pre-setting devices shall be easily accessible and not be able to fall into the gas way of the
manual gas valve.
The operation of pre-setting devices shall only be possible with a tool.
Pre-setting devices shall be fixed in their set positions.
6.101.8 Compensation means for manual gas valves
Manual gas valves shall be designed with compensating means to take up automatically any wear
between the closure member and the valve body.
6.101.9 Spring effect in manual gas valves
The tapered plug shall be held in position in the body by a spring. The construction shall be such that
any play between plug and valve body caused by wear which can be expected during normal life shall
be taken up automatically.
6.101.10 Manual gas valves with two or more “on” positions
A manual gas valve having an intermediate “off” position between two or more “on” positions shall be so
constructed that it will become latched in the “off” position.
6.102 Appliance connector valves
6.102.1 Appliance connector valves shall have inlet and outlet connections in accordance with
Table 1.
Table 1 — Inlet and outlet connections of appliance connector valves
Inlet connection Outlet connection
[Female iron pipe size (I.P.S.)] (Fitting for flared tubing connection)
mm
mm
9,5 9,5
12,7 12,7
19,1 19,1
6.102.2 An appliance connector valve shall have a non-displaceable valve member (see Figure 1).
If the small end of the plug is exposed, it shall be recessed in the body a minimum of 1,6 mm.
Key
1 flare tubing connection
2 spring and handle design such that plug cannot be displaced
3 taper pipe threads
4 if small end of plug is exposed, the plug shall be recessed at least in 1,6 mm
5 gasway
Figure 1 — Appliance connector valve with non-displaceable valve member
7 Performance
7.1 General
Shall be according to ISO 23550:2011, 7.1.
7.2 Leak-tightness
7.2.1 Criteria
Shall be according to ISO 23550:2011, 7.2.1.
NOTE Regional specific requirements are given in Annex F.
7.2.2 Test for leak-tightness
Shall be according to ISO 23550:2011, 7.2.2.
NOTE Regional specific requirements are given in Annex
...