Safety and control devices for gas burners and gas burning appliances - Part 2: Pressure regulators for inlet pressures above 50 kPa up to and including 500 kPa and associated safety devices

This European Standard specifies the safety, construction and performance requirements for pressure regulators (hereafter referred to as regulators) intended for use with gas burners and gas-burning appliances using fuel gases of the 1st, 2nd and 3rd families. This European Standard covers type testing only. It also provides additional information for the purchaser and user.
This European Standard is applicable to regulators that may be tested independently of gas burners and gas-burning appliances, which have a declared working pressure from above 500 mbar up to and including 5 bar.
This European Standard is also applicable to regulators incorporating safety devices.
NOTE 1   For safety accessories and pressure accessories, the requirements of EN 13611:2000, Annex F also apply.
NOTE 2   Regulators conforming to EN 88-2 fulfil also the requirements of EN 88-1.
Regulators intended to be used on pipe work installations for third family gases are also covered by EN 13785 and EN 13786.
This European Standard is not applicable to:
a)   pressure regulators that are connected directly to mains pipe-work or to a container that maintains a standard distribution pressure;
b)   pressure regulators which use electrical auxiliary energy.
pressure;
b)   pressure regulators which use electrical auxiliary energy.

Sicherheits- und Regeleinrichtungen für Gasbrenner und Gasgeräte - Teil 2: Druckregler für Eingangsdrücke über 50 kPa bis einschließlich 500 kPa und dazugehörigen Sicherheitseinrichtungen

Es gilt EN 13611:2019, Abschnitt 1 mit der folgenden Änderung und der folgenden Ergänzung:
Änderung:
Der 1. Absatz von EN 13611:2019, Abschnitt 1, wird durch Folgendes ersetzt:
Dieses Dokument legt die Sicherheits-, Auslegungs-, Konstruktions- und Leistungs¬anforderungen sowie die Prüfung von pneumatischen Druckreglern und Sicherheitseinrichtungen für Brenner und Brennstoffgeräte für einen oder mehrere gasförmige(n) Brennstoff(e) oder flüssige Brennstoffe, die im Folgenden als „Druckregler“ bezeichnet werden.
Dieses Dokument gilt für Druckregler mit angegebenen höchsten Eingangsdrücken über 50 kPa und bis einschließlich 500 kPa mit Anschlussnennweiten bis einschließlich DN 250.
Ergänzung:
Dieses Dokument ist anwendbar auf:
-   Druckregler mit integrierten Sicherheitseinrichtungen;
-   Druckregler und Sicherheitseinrichtungen, die elektrische Hilfsenergie benötigen;
-   unabhängige Druckregler oder Druckregler mit einer Regeleinrichtung für höchsten oder niedrigsten Gasdruck.
Dieses Dokument ist nicht anwendbar auf:
-   Druckregler, die unmittelbar an ein Gasverteilungsnetz oder an einen Behälter mit genormtem Verteilungsdruck angeschlossen sind;
-   Druckregler für Gasgeräte in Freiluftausführung, die Umwelteinflüssen ausgesetzt sind.

Dispositifs de sécurité et de contrôle pour les brûleurs à gaz et appareils utilisant des combustibles gazeux - Partie 2 : Régulateurs de pression pour pressions amont comprises entre 50 kPa et 500 kPa et dispositifs de sécurité associés

L’article 1 de la norme EN13611 :2019 s’applique avec la modification et l’addition suivantes :
Modification :
Le 1er paragraphe de l’article 1 de la norme EN13611 :2019 est remplacé par ce qui suit :
Le présent document prescrit les exigences et essais de sécurité, de conception, de construction et de fonctionnement relatives aux régulateurs de pression pneumatiques et dispositifs de sécurité pour brûleurs et appareils utilisant un ou plusieurs combustibles gazeux, dénommés ci-après « régulateurs de pression ».
Le présent document est applicable aux régulateurs de pression dont la pression amont maximale est comprise entre 50 kPa et 500 kPa, de diamètre nominal de raccordement inférieur ou égal à DN 250.
Addition :
Le présent document est applicable :
-   aux régulateurs de pression à dispositifs de sécurité intégrés ;
-   aux régulateurs de pression et aux dispositifs de sécurité qui utilisent une énergie électrique auxiliaire ; et
-   aux régulateurs de pression autonomes ou aux régulateurs de pression équipés d'un dispositif de régulation pour pression de gaz maximale ou minimale.
Le présent document ne s'applique pas :
-   aux régulateurs de pression qui sont raccordés directement au réseau de distribution ou à un récipient qui maintient en aval une valeur de pression de distribution normalisée ;
-   aux régulateurs de pression destinés à des appareils à gaz qui doivent être installés en plein air et exposés aux intempéries.
Le 4ième paragraphe de l’article 1 de la EN 13611 :2019 est supprimé.

Varnostne in nadzorne naprave za plinske gorilnike in plinske aparate - 2. del: Regulatorji tlaka za vstopne tlake nad 50 kPa do vključno 500 kPa in pripadajoče varnostne naprave

General Information

Status
Not Published
Public Enquiry End Date
02-Jun-2020
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
26-Oct-2022
Due Date
31-Dec-2022

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SLOVENSKI STANDARD
oSIST prEN 88-2:2020
01-maj-2020
Varnostne in nadzorne naprave za plinske gorilnike in plinske aparate - 2. del:
Regulatorji tlaka za vstopne tlake nad 50 kPa do vključno 500 kPa in pripadajoče
varnostne naprave

Safety and control devices for gas burners and gas burning appliances - Part 2: Pressure

regulators for inlet pressures above 50 kPa up to and including 500 kPa and associated

safety devices

Sicherheits- und Regeleinrichtungen für Gasbrenner und Gasgeräte - Teil 2: Druckregler

für Eingangsdrücke über 50 kPa bis einschließlich 500 kPa und dazugehörigen
Sicherheitseinrichtungen

Dispositifs de sécurité et de contrôle pour les brûleurs à gaz et appareils utilisant des

combustibles gazeux - Partie 2 : Régulateurs de pression pour pressions amont
comprises entre 50 kPa et 500 kPa et dispositifs de sécurité associés
Ta slovenski standard je istoveten z: prEN 88-2
ICS:
23.060.40 Tlačni regulatorji Pressure regulators
27.060.20 Plinski gorilniki Gas fuel burners
oSIST prEN 88-2:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 88-2:2020
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oSIST prEN 88-2:2020
DRAFT
EUROPEAN STANDARD
prEN 88-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2020
ICS 23.060.40 Will supersede EN 88-2:2007
English Version
Pressure regulators and associated safety devices for gas
appliances - Part 2: Pressure regulators for inlet pressures
above 500 mbar up to and including 5 bar

Dispositifs de sécurité et de contrôle pour les brûleurs Sicherheits- und Regeleinrichtungen für Gasbrenner

à gaz et appareils utilisant des combustibles gazeux - und Gasgeräte - Teil 2: Druckregler für Eingangsdrücke

Partie 2 : Régulateurs de pression pour pressions über 50 kPa bis einschließlich 500 kPa und

amont comprises entre 50 kPa et 500 kPa et dispositifs dazugehörigen Sicherheitseinrichtungen

de sécurité associés

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 58.

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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 88-2:2020 E

worldwide for CEN national Members.
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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 5

Introduction .................................................................................................................................................................... 6

1 Scope .................................................................................................................................................................... 7

2 Normative references .................................................................................................................................... 7

3 Terms and definitions ................................................................................................................................... 8

4 Classification .................................................................................................................................................. 12

4.1 Classes of control .......................................................................................................................................... 12

4.2 Groups of control .......................................................................................................................................... 13

4.3 Classes of control function ........................................................................................................................ 13

4.4 Types of DC supplied controls ................................................................................................................. 13

5 Test conditions and uncertainty of measurements ......................................................................... 13

6 Design and construction ............................................................................................................................ 13

6.1 General ............................................................................................................................................................. 13

6.2 Mechanical parts of the control .............................................................................................................. 13

6.2.1 Appearance ..................................................................................................................................................... 13

6.2.2 Holes ................................................................................................................................................................. 13

6.2.3 Breather holes ............................................................................................................................................... 13

6.2.4 Screwed fastenings ...................................................................................................................................... 13

6.2.5 Jointing ............................................................................................................................................................. 13

6.2.6 Moving parts .................................................................................................................................................. 13

6.2.7 Sealing caps .................................................................................................................................................... 13

6.2.8 Dismantling and reassembly ................................................................................................................... 14

6.2.9 Auxiliary canals and orifices .................................................................................................................... 14

6.2.10 Presetting device .......................................................................................................................................... 14

6.2.101 External visual Indication of the position of the closure member ..................................... 14

6.2.102 Parts transmitting actuating forces .............................................................................................. 14

6.2.103 Adjustments ........................................................................................................................................... 14

6.2.104 Integral safety shut-off device ......................................................................................................... 14

6.2.105 Resistance to pressure ....................................................................................................................... 15

6.2.106 Signal tube connections ..................................................................................................................... 15

6.2.107 Creep relief device ............................................................................................................................... 15

6.3 Materials .......................................................................................................................................................... 16

6.3.1 General material requirements .............................................................................................................. 16

6.3.2 Housing ............................................................................................................................................................ 16

6.3.3 Zinc alloys ....................................................................................................................................................... 16

6.3.4 Springs ............................................................................................................................................................. 16

6.3.5 Resistance to corrosion and surface protection ............................................................................... 16

6.3.6 Impregnation ................................................................................................................................................. 16

6.3.7 Seals for glands for moving parts ........................................................................................................... 16

6.4 Gas connections ............................................................................................................................................ 16

6.5 Electrical parts of the control .................................................................................................................. 16

6.6 Protection against internal faults for the purpose of functional safety ................................... 16

7 Performance .................................................................................................................................................. 16

7.1 General ............................................................................................................................................................. 16

7.2 Leak-tightness ............................................................................................................................................... 17

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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)

7.2.1 Requirements ................................................................................................................................................. 17

7.2.2 Tests .................................................................................................................................................................. 17

7.3 Torsion and bending ................................................................................................................................... 17

7.4 Rated flow rate .............................................................................................................................................. 17

7.4.1 Requirement ................................................................................................................................................... 17

7.4.2 Test .................................................................................................................................................................... 17

7.4.3 Conversion of air flow rate ........................................................................................................................ 17

7.5 Durability......................................................................................................................................................... 17

7.5.1 Elastomers in contact with gas ................................................................................................................ 17

7.5.2 Marking ............................................................................................................................................................ 18

7.5.3 Resistance to scratching ............................................................................................................................. 18

7.5.4 Resistance to humidity ............................................................................................................................... 18

7.6 Performance tests for electronic controls ........................................................................................... 18

7.7 Long-term performance for electronic controls ............................................................................... 18

7.8 Data exchange ................................................................................................................................................ 18

7.101 Pressure regulator performance ............................................................................................................ 18

7.101.1 General ..................................................................................................................................................... 18

7.101.2 General test procedure ....................................................................................................................... 18

7.102 Safety devices ................................................................................................................................................. 24

7.102.1 Over-pressure safety shut-off devices .......................................................................................... 24

7.102.2 Under-pressure safety shut-off devices ....................................................................................... 28

7.102.3 Endurance ............................................................................................................................................... 28

8 Electrical requirements .............................................................................................................................. 29

9 Electromagnetic compatibility (EMC) ................................................................................................... 29

10 Marking, installation and operating instructions ............................................................................. 29

10.1 Marking ............................................................................................................................................................ 29

10.2 Installation and operating instructions ............................................................................................... 30

10.3 Warning notice .............................................................................................................................................. 30

Annex A (informative) Abbreviations and Symbols ...................................................................................... 31

Annex B (informative) Leak-tightness tests for gas controls – volumetric method .......................... 32

Annex C (informative) Leak-tightness tests for gas controls – pressure loss method ...................... 33

Annex D (normative) Conversion of pressure loss into leakage rate ..................................................... 34

Annex E (normative) Electrical/electronic component fault modes ...................................................... 35

Annex F (normative) Additional requirements for safety accessories and pressure

accessories as defined in EU Directive 97/23/EC ............................................................................. 36

Annex G (normative) Materials for pressurized parts ................................................................................. 37

Annex H (normative) Additional materials for pressurized parts .......................................................... 38

Annex I (normative) Requirements for controls used in DC supplied burners and

appliances burning gaseous or liquid fuels......................................................................................... 39

Annex J (normative) Method for the determination of a Safety Integrity Level (SIL) ....................... 40

Annex K (normative) Method for the determination of a Performance Level (PL) ........................... 41

Annex L (informative) Relationship between Safety Integrity Level (SIL) and Performance

Level (PL) ......................................................................................................................................................... 42

Annex M (normative) Reset functions ................................................................................................................ 43

Annex N (informative) Guidance document on environmental aspects ................................................ 44

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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)

Annex O (normative) Seals of elastomer, cork and synthetic fibre mixtures ...................................... 45

Annex AA (informative) Typical pressure regulators and pressure regulator parts ....................... 46

AA.1 Main components of a pressure regulator .......................................................................................... 46

AA.2 Main components of a gas safety shut-off device .............................................................................. 49

Annex BB (informative) Overview of requirements and test conditions (as given in

Clause 7), and examples of performance curves for pressure regulators ............................... 51

Annex CC (normative) Creep relief device ....................................................................................................... 54

CC.1 General ............................................................................................................................................................. 54

CC.2 Terms and definitions ................................................................................................................................ 54

CC.3 Design and construction ............................................................................................................................ 54

CC.4 Performance requirements ...................................................................................................................... 54

CC.5 Marking, installation and operating instructions ............................................................................ 55

Annex DD (informative) Comparison between EN 334:2005+A1:2009 and prEN 88-2:2020 ....... 56

Annex ZA (informative) Relationship between this European Standard and the essential

requirements of Regulation (EU) 2016/426 aimed to be covered ............................................. 57

Annex ZB (informative) Relationship between this European Standard and the essential

requirements of Directive 2014/68/EU aimed to be covered ..................................................... 63

Bibliography ................................................................................................................................................................. 65

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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
European foreword

This document (prEN 88-2:2020) 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 document will supersede EN 88-2:2007.

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 Directive(s).

For relationship with EU Directive(s), see informative Annexes ZA and ZB, which are an integral part of

this document.

prEN 88-2:2020 includes the following significant technical changes with respect to EN 88-2:2007:

a) scope extended to “Pressure regulators incorporating safety devices”;
b) alignment with EN 13611:2019;

c) requirements and tests added for pressure regulators which use auxiliary energy;

d) classifications according to accuracy, lock-up pressure, and over-pressure shut-off added;

e) Clause 6 extended to “Design and construction”;
f) Clause 6.2.104 “Integral safety shut-off device” added;
g) Clause 6.2.105 “Resistance to pressure” added;
h) Clause 6.2.107 “Creep relief device” added;
i) Clause 7.2.2 “Test for leak-tightness”, new value for test pressure;
j) design of all Figures adapted to design of Figures in EN 13611:2019;
k) Annex BB “Overview of requirement and test conditions” added;
l) Annex CC “Creep relief device” added;
m) Annex DD “Comparison between EN 334:2005+A1:2009 and prEN 88-2:2020” added.
EN 88 consists of the following parts:
— Part 1: Pressure regulators for inlet pressures up to and including 50 kPa;

— Part 2: Pressure regulators for inlet pressures above 500 mbar up to and including 5 bar;

— Part 3: Pressure and/or flow rate regulators for inlet pressures up to and including 500 kPa, electronic

types.
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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
Introduction

This document is a particular standard for pressure Regulators for gas-burners and gas-burning

appliances which cites the generic requirements of EN 13611:2019 wherever possible. This document

supplements or modifies the corresponding clauses of EN 13611:2019. The construction and

performance requirements are as far as applicable in total conformity with EN 13611:2019.

This document is intended to be used in conjunction with EN 13611:2019. This document refers to

clauses of EN 13611:2019 or adapts clauses by stating “with the following modification”, “with the

following addition”, “is replaced by the following” or “is not applicable” in the corresponding clause.

This document adds clauses or subclauses to the structure of EN 13611:2019 which are particular to

this document. It should be noted that these clauses and subclauses are not indicated as an addition.

Subclauses which are additional to those in EN 13611:2019 are numbered starting from 101. Additional

Annexes are designed as Annex AA, BB, CC, etc.

Performance Level (PL) or Safety Integrity Level (SIL) classifications according to EN ISO 13849-1 or

EN 61508-1 cannot automatically be claimed based upon compliance with this document. Pressure

regulators with SIL classification do not automatically meet the requirements of this document.

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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
1 Scope

This document specifies the safety, design, construction as well as performance requirements and

testing for pneumatic pressure regulators and safety devices for burners and appliances burning one or

more gaseous fuels, hereafter referred to as ‘pressure regulators’.
This document is applicable to:

— pressure regulators with declared maximum inlet pressure above 50 kPa up to and including

500 kPa, of nominal connection size up to and including DN 250 for use with one or more fuel gases

in accordance with EN 437;
— pressure regulators incorporating safety devices;
— pressure regulators and safety devices which use auxiliary energy; and

— stand-alone pressure regulators or pressure regulators equipped with a control device for

maximum or minimum gas pressure.
This document is not applicable to:

— pressure regulators that are connected directly to mains pipe-work or to a container that maintains

a standard distribution pressure;

— pressure regulators intended for gas appliances to be installed in the open air and exposed to the

environment.
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 549, Rubber materials for seals and diaphragms for gas appliances and gas equipment

EN 682, Elastomeric Seals - Materials requirements for seals used in pipes and fittings carrying gas and

hydrocarbon fluids

EN 13611:2019, Safety and control devices for burners and appliances burning gaseous and/or liquid

fuels - General requirements

EN 13787, Elastomers for gas pressure regulators and associated safety devices for inlet pressures up to

100 bar

EN 60534-2-3:2016, Industrial-process control valves - Part 2-3: Flow capacity - Test procedures (IEC

60534-2-3)
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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN 13611:2019 and the following

apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.101
pressure regulator

device that maintains the outlet pressure constant independent of the variations in inlet pressure

and/or flow rate within defined limits
[SOURCE: EN 88-1:2011+A1:2016, 3.101]
3.102
control member

movable part of the pressure regulator which varies flow rate and/or outlet pressure directly

[SOURCE: EN 88-1:2011+A1:2016, 3.107]
3.103
safety shut-off device
SSD

device the function of which is to stay in the open position under normal operating conditions and to

shut off the gas flow automatically and completely when the monitored pressure deviates above or

below the pre-set value
3.104
housing

part of the pressure regulator and/or SSD that is the main pressure containing envelope

3.105
valve seat

corresponding sealing surfaces within a pressure regulator or SSD that make full contact only when the

pressure regulator or SSD is in the closed position
3.106
controller

device which normally includes a setting element, normally a spring, to obtain a set value of the outlet

pressure and a pressure detector element, normally a diaphragm for the outlet pressure

3.107
actuator

device or mechanism which changes the signal from the controller into a corresponding movement

controlling the position of the control member
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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
3.108
working diaphragm

flexible member which, under the influence of the forces arising from loading and pressure, operates

the control member

Note 1 to entry: Diaphragms used as a control member are not covered by this definition.

3.109
pressure containing part
part where failure would result in release of gas to the atmosphere

Note 1 to entry: Such parts comprise housings, inner partition walls, control member, bonnets, the housing of

the actuator, blind flanges and pipes for process and sensing lines.
3.110
signal connection

part that is used to convey pressure from part of an installation to the signal chamber

3.111
breather line

line between the controller and/or pilot regulator and atmosphere which equalizes the pressure on a

detector element when it changes its position
3.112
fixture

functional device connected to the main components of the pressure regulator or SSD

3.113
exhaust line

line to atmosphere between the regulator or fixtures for the safe venting of gas in the event of a

component failure
3.114
trip mechanism
mechanism that releases the closure member when activated by the controller
3.115
SSD-actuator
device that is activated by the trip mechanism which shuts the closure member
3.116
relatching device
device that enables the complete opening of an SSD
3.117
motorization chamber

chamber at the higher pressure of two chambers under pressure within the housing of actuator

3.118
monitored pressure
pressure monitored and safeguarded by the SSD
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oSIST prEN 88-2:2020
prEN 88-2:2020 (E)
3.119
trip pressure
pressure value at which the closing member starts to move
3.120
upper trip pressure
upper limit of the monitored over-pressure
3.121
lower trip pressure
lower limit of the monitored under-pressure
3.122
outlet setting pressure
outlet pressure at which the pressure regulator is set for test purposes
[SOURCE: EN 88-1:2011+A1:2016, 3.113]
3.123
maximum outlet pressure
2max

upper limit of the outlet pressure, as stated in the installation and operating instructions

[SOURCE: EN 88-1:2011+A1:2016, 3.109]
3.124
minimum outlet pressure
2min

lower limit of the outlet pressure, as stated in the installation and operating instructions

[SOURCE: EN 88-1:2011+A1:2016, 3.110]
3.125
outlet pressure
...

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