Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use - Part 2: System E - Safety

This European Standard specifies the requirements and test methods for the construction, safety, classification and marking of non-domestic gas-fired overhead radiant tube heaters incorporated into a multi-burner system (referred to in the body of the text as the 'system') with each burner unit under the control of an automatic burner control system.  This standard is applicable to Type B22 and Type B23 systems (see 4.3) intended for use in other than domestic dwellings, in which the supply of combustion air and/or the evacuation of the products of combustion is achieved by mechanical means.  This standard is not applicable to:  -systems designed for use in domestic dwellings; -outdoor systems; -systems in which the heat input of an individual burner unit exceeds 120 kW (based on the net calorific value of the appropriate reference test gas); -systems having a draught diverter incorporated between the exhaust fan and the flue duct; -systems having fully pre-mixed gas and air burners in which: -either the gas and all the combustion air are brought together just before the level of the combustion zone; -or the pre-mixing of the gas and all combustion air is carried out in a part of the burner upstream of the combustion zone.  This European Standard is applicable to systems which are intended to be type tested. Requirements for systems which are not intended to be type tested would need to be subject to further consideration.  Requirements concerning the rational use of energy have not been included in this European Standard.

Dunkelstrahlersysteme mit mehreren Brennern mit Gebläse für gewerbliche und industrielle Anwendung - Teil 2: System E - Sicherheit

Diese Europäische Norm enthält die Anforderungen und Prüfmethoden für Bauausführung, Sicherheit, Klassifizierung und Kennzeichnung für Dunkelstrahler als Bestandteil eines Systems mit mehreren Brennern (genannt System E und im folgenden Text als System bezeichnet), wobei jede einzelne Brennereinheit von einem Gasfeuerungsautomaten überwacht wird.
Diese Europäische Norm gilt für Systeme der Arten B52 und B53 (siehe 4.3), die für gewerbliche und industrielle Anwendung vorgesehen sind und bei denen die Zufuhr der Verbrennungsluft und/oder die Abführung der Verbrennungsprodukte mit mechanischen Mitteln erfolgt.
Diese Europäische Norm gilt nicht für:
a)   Systeme, die für eine Verwendung in Wohnungen gedacht sind;
b)   Systeme, die für eine Verwendung im Freien gedacht sind;
c)   Systeme mit einer Wärmebelastung über 120 kW (bezogen auf den Heizwert des jeweiligen Normprüfgases);
d)   Systeme mit einer Strömungssicherung zwischen dem Gebläse und der Abgasabführungsleitung;
e)   Systeme mit Brennern mit kompletter Gas- und Luftvormischung, bei denen:
1)   entweder das Gas und die gesamte Verbrennungsluft kurz vor der Verbrennungszone zusammengeführt werden; oder
2)   das Vormischen des Gases mit der gesamten Verbrennungsluft in einem Teil des Brenners vor der Verbrennungszone erfolgt.
f)   Systeme, die für kontinuierliche Kondensation im Abgassystem bei normalen Betriebsbedingungen ausgelegt sind;
g)   Systeme mit Abgassystem aus nichtmetallenen Werkstoffen.
Diese Norm ist anwendbar für Systeme, die für eine Typprüfung vorgesehen sind. Sie enthält auch Anforderungen an die Entwicklung von Übereinstimmung einschließlich Fertigungskontrolle, aber diese Anforderungen gelten nur für POCEDs und deren dazugehörende Windschutzeinrichtungen.
ANMERKUNG   Anforderungen an Systeme, die nicht für eine Typprüfung vorgesehen sind, benötigen weitere Überlegungen.

Tubes radiants suspendus à multi-brûleurs utilisant les combustibles gazeux à usage non-domestique - Partie 2 : Système E - Sécurité

La présente Norme européenne définit les exigences et les méthodes d'essai relatives a la construction, la sécurité, la classification et le marquage des tubes radiants suspendus utilisant les combustibles gazeux, a usage non domestique, intégrés dans un systeme a multi-bruleurs (appelé ci-apres « systeme E» et désigné dans le corps du texte par « systeme »), chaque bruleur élémentaire étant équipé d'un systeme automatique de commande et de sécurité.
La présente Norme européenne est applicable aux systemes de Types B52 et B53 (voir en 4.3), destinés a etre utilisés ailleurs que dans des locaux d’habitation domestiques pour lesquels l'alimentation en air comburant et/ou l'évacuation des produits de combustion est assurée par des moyens mécaniques.
La présente Norme européenne ne s'applique pas :
a) aux systemes conçus pour des locaux domestiques ;
b) aux systemes utilisés en plein air ;
c) aux systemes dont le débit calorifique dépasse 120 kW (par rapport au pouvoir calorifique inférieur du gaz d’essai de référence approprié) ;
d) aux systemes disposant d'un coupe-tirage antirefouleur entre le ventilateur d’extraction et le conduit d’évacuation ;
e) aux systemes avec bruleurs a prémélange total dans lesquels :
1) le gaz et tout l'air comburant sont mélangés juste avant la zone de combustion ; ou
2) le prémélange du gaz et de tout l'air comburant est transporté dans une partie du bruleur en amont de la zone de combustion.
f) aux systemes conçus pour une condensation continue dans le systeme d'évacuation dans des conditions de fonctionnement normales ;
g) aux systemes équipés de conduits d'évacuation des produits de combustion non métalliques.
La présente norme est applicable aux systemes qui sont destinés a subir des essais de type. Elle comprend également des exigences relatives a l'évaluation de la conformité, y compris le contrôle de fabrication en usine, ces dernieres exigences ne s’appliquant toutefois exclusivement qu’aux POCED et (...)

Stropna cevna sevala z več plinskimi gorilniki za nestanovanjske prostore - 2. del: Sistem E - Varnost

General Information

Status
Withdrawn
Public Enquiry End Date
19-Oct-2006
Publication Date
09-Jun-2009
Withdrawal Date
04-Dec-2019
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
04-Dec-2019
Due Date
27-Dec-2019
Completion Date
05-Dec-2019

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SLOVENSKI STANDARD
SIST EN 777-2:2009
01-julij-2009
1DGRPHãþD
SIST EN 777-2:1999
SIST EN 777-2:1999/A1:2002
SIST EN 777-2:1999/A2:2002
SIST EN 777-2:1999/A3:2003
6WURSQDFHYQDVHYDOD]YHþSOLQVNLPLJRULOQLNL]DQHVWDQRYDQMVNHSURVWRUHGHO
6LVWHP(9DUQRVW
Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use - Part
2: System E - Safety
Dunkelstrahlersysteme mit mehreren Brennern mit Gebläse für gewerbliche und
industrielle Anwendung - Teil 2: System E - Sicherheit
Tubes radiants suspendus à multi-brûleurs utilisant les combustibles gazeux à usage
non-domestique - Partie 2 : Système E - Sécurité
Ta slovenski standard je istoveten z: EN 777-2:2009
ICS:
97.100.20 Plinski grelniki Gas heaters
SIST EN 777-2:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 777-2:2009

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SIST EN 777-2:2009
EUROPEAN STANDARD
EN 777-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2009
ICS 91.140.40 Supersedes EN 777-2:1999
English Version
Multi-burner gas-fired overhead radiant tube heater systems for
non-domestic use - Part 2: System E - Safety
Tubes radiants suspendus à multi-brûleurs utilisant les Gasgeräte-Heizstrahler - Dunkelstrahlersysteme mit
combustibles gazeux à usage non-domestique - Partie 2 : mehreren Brennern mit Gebläse für gewerbliche und
Système E - Sécurité industrielle Anwendung - Teil 2: System E - Sicherheit
This European Standard was approved by CEN on 24 January 2009.
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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 777-2:2009: E
worldwide for CEN national Members.

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SIST EN 777-2:2009
EN 777-2:2009 (E)
Contents Page
Foreword . 4
1 Scope. 5
2 Normative references . 5
3 Terms and definitions . 6
3.1 System and its constituent parts . 6
3.2 Adjusting, control and safety devices . 9
3.3 System operation . 10
3.4 Gases. 13
3.5 Conditions of operation and measurement. 14
3.6 Country of destination . 14
4 System classification. 15
4.1 Classification according to the nature of the gases used (categories) . 15
4.2 Classification according to the gases capable of being used . 15
4.3 Classification according to the mode of evacuation of the combustion products . 17
5 Constructional requirements . 17
5.1 General . 17
5.2 Requirements for adjusting, control and safety devices . 22
5.3 Ignition devices . 27
5.4 Main burners . 27
5.5 Pressure test points . 27
5.6 Injectors . 28
6 Operational requirements . 28
6.1 Soundness . 28
6.2 Heat inputs . 28
6.3 Limiting temperatures . 29
6.4 Ignition, cross-lighting and flame stability . 29
6.5 Pressure regulator . 29
6.6 Combustion . 30
6.7 Prolonged performance. 30
6.8 Measurement of oxides of Nitrogen, NO . 31
x
7 Test methods . 31
7.1 General . 31
7.2 Construction and design . 38
7.3 Safety of operation . 38
7.4 Other pollutants . 51
8 Marking and instructions . 54
8.1 Marking of the system and the packaging . 54
8.2 Instructions . 58
8.3 Presentation . 62
9 Evaluation of conformity of POCEDs and their associated terminals . 62
9.1 General . 62
9.2 Type testing . 62
9.3 Factory production control (FPC) . 63
Annex A (informative) National situations . 65
A.1 General . 65
A.2 Categories listed in the body of the standard and marketed in different countries . 65
A.3 Appliance supply pressures corresponding to the categories given in A.2 . 67
2

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SIST EN 777-2:2009
EN 777-2:2009 (E)
A.4 Special categories marketed nationally or locally . 69
A.5 Test gases corresponding to the special categories given in A.4 . 73
A.6 Gas connections in the various countries . 74
A.7 Flue connections in the various countries . 76
Annex B (informative) System E . 77
Annex C (informative) Equivalence rules . 78
C.1 Conversion to categories within a restricted Wobbe Index range . 78
C.2 Conversion to categories within an identical Wobbe Index range . 78
C.3 Conversion to categories within a wider Wobbe Index range. 79
Annex D (informative) Calculation of flue gas mass flow rate . 80
D.1 Flue gas mass flow rate. 80
D.2 Quantity of air in the flue gas . 80
D.3 Flue gas excess air ratio (λ) . 81
D.4 Quantity of water vapour in the flue gas . 81
D.5 Quantity of Nitrogen in the flue gas . 81
D.6 Quantity of Oxygen in the flue gas . 82
D.7 Dry quantity of flue gas . 82
D.8 Quantity of carbon dioxide in the flue gas . 82
Annex E (informative) Identification of gas types in use in various countries . 84
Annex F (normative) Special national conditions . 85
F.1 General . 85
Annex G (informative) Calculation example of the weighting factors for a system with
several rates . 86
G.1 Appliance rates . 86
G.2 Weighting of Q = 20 . 86
pi,%
G.3 Weighting of Q = 40 . 86
pi,%
G.4 Weighting of Q = 60 . 86
pi,%
G.5 Weighting of Q = 70 . 87
pi,%
G.6 Total weighting . 87
Annex H (informative) NO conversion calculation . 88
x
H.1 NO emission conversion factors. 88
x
H.2 NO Conversion — Calculation . 89
x
Annex I (informative) National situations of countries whose national bodies are CEN
associate members . 91
Annex J (informative) An example of sampling plans . 92
J.1 Sampling plans . 92
J.2 Inspection levels and procedures . 93
Annex K (informative) Flue determination . 94
K.1 General conditions of test . 94
K.2 Test conditions . 94
K.3 Test procedure . 94
K.4 Accuracy of measurement . 96
K.5 Calculation of Flue Loss. 96
Annex ZA (informative) Clauses of this European Standard addressing essential
requirements or other provisions of EU Directives . 99
Annex ZB (informative) Clauses of this European Standard addressing the provisions of
the EU Construction Products Directive . 102
ZB.1 Scope and relevant characteristics . 102
ZB.2 Procedure(s) for attestation of conformity of [construction products] . 104
ZB.3 CE marking and labelling . 107
Bibliography . 109

3

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SIST EN 777-2:2009
EN 777-2:2009 (E)
Foreword
This document (EN 777-2:2009) has been prepared by Technical Committee CEN/TC 180 “Domestic
and non-domestic gas fired air heaters and non-domestic gas fired overhead radiant heaters”, the
secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by September 2009, and conflicting national standards
shall be withdrawn at the latest by September 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such
patent rights.
This document supersedes EN 777-2:1999.
This revision modifies EN 777-2:1999. It has been prepared to incorporate requirements for
combustion products evacuation ducts, POCEDs, supplied as an integral part of the system to
support the EU Directive 89/106/EEC on construction products under mandate M/105. To this end the
systems within the scope of this standard are now defined as Type B and Type B rather than Type
52 53
B and Type B .
22 23
Furthermore, the opportunity presented by this revision has been taken to update the standard in
respect to EN 437:2003.
This document has been prepared under a mandate given to CEN by the European Commission and
the European Free Trade Association, and supports essential requirements of EC Directive(s).
For relationship with EC Directive(s), see informative Annexes ZA and ZB, which are integral parts of
this document.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
4

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SIST EN 777-2:2009
EN 777-2:2009 (E)
1 Scope
This European Standard specifies the requirements and test methods for the construction, safety,
classification and marking of non-domestic gas-fired overhead radiant tube heaters incorporated into a
multi-burner system (called system E and referred to in the body of the text as the 'system') with each
burner unit under the control of an automatic burner control system.
This standard is applicable to Type B and Type B systems (see 4.3) intended for use in other than
52 53
domestic dwellings, in which the supply of combustion air and/or the evacuation of the products of
combustion is achieved by mechanical means.
This standard is not applicable to:
a) systems designed for use in domestic dwelling;
b) outdoor systems;
c) systems of heat input in excess of 120 kW (based on the net calorific value of the appropriate
reference test gas);
d) systems having a draught diverter between the exhaust fan and the flue duct;
e) systems having fully pre-mixed gas and air burners in which:
1) either the gas and all the combustion air are brought together just before the level of the
combustion zone; or
2) the pre-mixing of the gas and all combustion air is carried out in a part of the burner upstream
of the combustion zone;
f) systems that are designed for continuous condensation within the flue system under normal
operating conditions;
g) systems having combustion products evacuation ducts that are non-metallic.
This standard is applicable to systems which are intended to be type tested. It also includes requirements
concerning the evaluation of conformity, including factory production control, but these requirements only
apply to POCEDs and their associated terminals.
NOTE Requirements for systems which are not intended to be type tested would need to be subject to
further consideration.
Requirements concerning the rational use of energy have not been included in this European Standard.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the editions cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 88-1:2007, Pressure regulators and associated safety devices for gas appliances - Part 1:
Pressure regulators for inlet pressures up to and including 500 mbar
EN 126:2004, Multifunctional controls for gas burning appliances
EN 161:2007, Automatic shut-off valves for gas burners and gas appliances
5

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SIST EN 777-2:2009
EN 777-2:2009 (E)
EN 257, Mechanical thermostats for gas-burning appliances
EN 298:2003, Automatic gas burner control systems for gas burners and gas burning appliances with
or without fans
EN 437:2003, Test gases - Test pressures - Appliance categories
EN 10226-1:2004, Pipe threads where pressure-tight joints are made on the threads – Part 1:Taper
external threads and parallel internal threads. Dimensions, tolerances and designation
EN 10226-2:2005, Pipe threads where pressure tight joints are made on the threads – Part2: Taper
external threads and taper internal threads. Dimensions, tolerances and designation
EN 60335-1:2002, Household and similar electrical appliances – Safety - Part 1: General
requirements
EN 60335-2-102:2006, Household and similar electrical appliances – Safety - Part 2-102: Particular
requirements for gas, oil and solid-fuel burning having electrical connections
EN 60529:1992, Degrees of protection provided by enclosures (IP code)
EN 60584-1:1995, Thermocouples — Part 1: Reference tables
EN 60584-2:1993, Thermocouples — Part 2: Tolerances
EN ISO 228-1:2003, Pipe threads where pressure-tight joints are not made on the threads - Part 1:
Dimensions, tolerances and designation (ISO 228-1:2000)
EN ISO 3166-1:2006, Codes for the representation of names of countries and their subdivisions –
Part 1: Country codes (ISO 3166-1:2006)
EN ISO 6976:2005, Natural gas - Calculation of the calorific values, density, relative density and
Wobbe index from composition (ISO 6976:1995 including Corrigendum 1:1997, Corrigendum 2:1997
and Corrigendum 3:1999)
ISO 7005-1:1992, Metallic flanges - Part 1: Steel flanges
ISO 7005-2:1988, Metallic flanges - Part 2: Cast iron flanges
ISO 7005-3:1988, Metallic flanges - Part 3: Copper flanges and composite flanges
CR 1404:1994, Determination of emissions from appliances burning gaseous fuels during type testing
3 Terms and definitions
For the purposes of this standard the following terms and definitions apply:
3.1 System and its constituent parts
3.1.1
overhead radiant tube heater
gas fired appliance intended for installation above head level which is designed to heat the space
beneath by radiation by means of a tube or tubes, heated by the internal passage of combustion products
6

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SIST EN 777-2:2009
EN 777-2:2009 (E)
3.1.2
multi-burner systems
those radiant tube heater systems which employ two or more burner units with each unit incorporating
independent flame monitoring.
NOTE - The units may be located in one or more sections of tubing. One or more fans may be used to assist
in the evacuation of products of combustion or the supply of combustion air
System E: system in which individual units with a fan are connected to a common duct without a fan.
Only one burner unit is situated in each branch tube. The fan may be at either end of the branch tube
(see 4.3 and Annex B)
3.1.3
branch tube
for the purposes of this part, a tube in which only one burner unit is situated and which only contains
the products of combustion generated by this burner
3.1.4
common duct
duct which receives products of combustion from two or more branch tubes for the purposes of
evacuation to the outside
3.1.5
individual burner unit
unit comprising a main burner and, if appropriate, an ignition burner. In addition, such components as
are necessary to ignite the burner(s), monitor the flame and control the gas supply to the burner(s) are
included in the unit
3.1.6
inlet connection
part of the system intended to be connected to the gas supply
3.1.7
mechanical joint (mechanical means of obtaining soundness)
means of ensuring the soundness of an assembly of several (generally metallic) parts without the use
of liquids, pastes, tapes, etc.
NOTE For example the following:
a) metal to metal joints;
b) conical joints;
c) toroidal sealing rings (“O” rings);
d) flat joints.
3.1.8
gas circuit
part of the burner unit that conveys or contains the gas between the burner unit gas inlet connection
and the burner(s)
3.1.9
restrictor
device with an orifice, which is placed in the gas circuit so as to create a pressure drop and thus
reduce the gas pressure at the burner to a predetermined value for a given supply pressure and rate
3.1.10
gas rate adjuster
component allowing an authorized person to set the gas rate of the burner to a predetermined value
according to the supply conditions
7

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SIST EN 777-2:2009
EN 777-2:2009 (E)
NOTE 1 Adjustment can be progressive (screw adjuster) or in discrete steps (by changing restrictors).
NOTE 2 The adjusting screw of an adjustable regulator is regarded as a gas rate adjuster.
NOTE 3 The action of adjusting this device is called “adjusting the gas rate”.
NOTE 4 A factory sealed gas rate adjuster is considered to be non-existent.
3.1.11
setting an adjuster
immobilizing a gas rate adjuster by such means as e.g. a screw after the gas rate has been adjusted
by the manufacturer or installer
3.1.12
sealing an adjuster
term applied to any arrangement in respect of the adjuster such that any attempt to change the
adjustment breaks the sealing device or sealing material and makes this interference apparent
NOTE A factory sealed adjuster, i.e. an adjuster sealed by the system manufacturer, is considered to be
non-existent.
A regulator is considered to be non-existent if it has been factory sealed, i.e. by the system manufacturer in a
position such that it is not operational in the range of the normal supply pressure corresponding to the system
category.
3.1.13
putting an adjuster or a control out of service
adjuster or a control (of temperature, pressure, etc.) is said to be “put out of service” if it is put out of
action and sealed in this position. The burner unit then functions as if this device has been removed
3.1.14
injector
component that admits the gas into a burner
3.1.15
main burner
burner that is intended to ensure the thermal function of the system and is generally called the burner
3.1.16
ignition device
means (e.g. flame, electrical ignition device or other device) used to ignite the gas at the ignition
burner or at the main burner
NOTE This device can operate intermittently or permanently.
3.1.17
ignition burner
burner whose flame is intended to ignite another burner
3.1.18
primary aeration adjuster
device enabling the primary air to be set at the desired value according to the supply conditions
3.1.19
combustion products circuit
circuit consisting of:
8

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SIST EN 777-2:2009
EN 777-2:2009 (E)
3.1.19.1
combustion chamber
enclosure inside which combustion of the air-gas mixture takes place
3.1.19.2
flue outlet
part of a Type B system that connects with a flue to evacuate the products of combustion
3.1.19.3
draught diverter
device placed in the combustion products circuit to reduce the influence of flue-pull and that of down-
draught on the burner performance and combustion
3.1.19.4
POCED
combustion products evacuation duct that is intended to be used only with a specific appliance/system;
this duct being either supplied with the appliance/system or specified in the manufacturer's instructions
3.1.20
range-rating device
component on the burner unit intended to be used by the installer to adjust the heat input of the
burner unit, within a range of heat inputs stated by the manufacturer, to suit the actual heat
requirements of the installation
This adjustment may be progressive (e.g. by use of a screw adjuster) or in discrete steps (e.g. by
changing restrictors).
3.1.21
zero regulator
device which maintains a specified downstream pressure between it and a gas orifice at zero
pressure within fixed limits independent of variation within a given range of upstream pre
...

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