• NEN EN 26 : 2015

    Current The latest, up-to-date edition.


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    Published date:  12-01-2013

    Publisher:  Netherlands Standards

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    Table of Contents - (Show below) - (Hide below)

    1 Scope
    2 Normative references
    3 Definitions
        3.1 instantaneous water heater
        3.2 characteristics of the gas and electricity supplies
        3.3 gas circuit
        3.4 adjusting, control and safety devices
        3.5 stages of operational and safety sequences
        3.6 burners
        3.7 combustion circuit
        3.8 water circuit
        3.9 soundness of the gas circuit
        3.10 operation
    4 Classification of water heaters
        4.1 Classification of gases
        4.2 Appliance categories
        4.3 Mode of supply of the combustion air and evacuation
        4.4 Water pressure
    5 Marking and instructions
        5.1 Appliance marking
        5.2 Instructions
        5.3 Presentation
    6 Constructional requirements
        6.1 General
        6.2 Adjusting, control and safety devices
        6.3 Main burner
    7 Operational requirements
        7.1 General
        7.2 Soundness
        7.3 Heat inputs
        7.4 Temperature of the control knobs
        7.5 Temperature of the adjusting, control and safety
        7.6 Temperature of the appliance case, the wall on
              which it is installed and adjacent walls
        7.7 Ignition - cross-lighting - Flame stability
        7.8 Adjusting, control and safety devices
        7.9 Combustion
        7.10 Soot deposition
    8 Rational use of energy
        8.1 Heat input of ignition burners
        8.2 Efficiency
    9 Fitness for purpose
        9.1 Constructional characteristics
        9.2 Operational characteristics
    A (informative) National situations (see 4.1)
        A.1 Marketing of the categories listed in the body
              of the European Standard in different countries
              see 4.2.1)
        A.2 Appliance supply pressures corresponding to the
              categories given in A.1(see 4.2.1)
        A.3 Particular categories marketed nationally or
              locally (see 4.2.1, 4.2.4, 5.1.1 and
        A.4 Test gases and pressures corresponding to the
              special categories given in A.3 (see 4.2.1,
              7.1.2 and 7.1.4)
        A.5 Additional marking corresponding to the
              particular categories given in A.3 (see 5.1.2)
        A.6 Particular conditions
        A.7 Gas connection conditions in common use in the
              various countries
        A.8 Water connection conditions in common use in the
              various countries (see 9.1.1)
        A.9 Flue pipe diameters in force in the various
              countries (see
    B (normative) Test apparatus for type C11 appliances
    C (normative) Test apparatus for type C21 appliances
    D (normative) Description of the sealed room for the tests
        of type Aas appliances (see
        D.1 Configuration of the sealed room
        D.2 Soundness of the room
        D.3 Effectiveness of mixing
        D.4 Equipment of the room
    E (informative) Soundness of the gas circuit test -
        Volumetric method (see and
        E.1 Equipment
        E.2 Test method
    F (informative) Principal symbols and abbreviations used
    G (informative) Guidelines for extension to other
        categories (see
    H (informative) Protection against electric shock for
        high voltage ignition devices (see 6.1.10)
        H.1 Protection against accessibility to live
              parts (see 8)
    J (informative) Examples of marking on the appliance
        J.1 Data plate
        J.2 Additional marking (see 5.1.2 and J.1)
    K (normative) Marking on the appliance and its packaging -
        Indication of the gas types in accordance with the
        uses declared by the countries in their official
        language(s)(see note 3 of table 2 from 5.1.2)
    ZA (informative) Clauses of this European Standard
        addressing Essential Requirements or other provisions
        of EU Directives

    Abstract - (Show below) - (Hide below)

    Specifies the specifications and test methods concerning the construction, safety, rational use of energy and fitness for purpose, and also the classification and marking of gas-fired instantaneous water heaters for sanitary uses, hereafter called 'water heaters'.

    General Product Information - (Show below) - (Hide below)

    Development Note Draft AMD 1 2016 issued in May 2016. (06/2016)
    Document Type Standard
    Publisher Netherlands Standards
    Status Current
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