BS EN 656:2000 PDF

1   Scope This standard specifies the requirements and test methods concerning, in particular the construction, safety, fitness for purpose, and rational use of energy, as well as the classification and marking of gas-fired central heating boilers that are fitted with atmospheric burners , fan assisted atmospheric burners or fully premixed burners , and are hereafter referred to as “boilers”. This standard applies to boilers of type B, as listed in 4.2:

              -  of the low-temperature type;

• that use one or more combustible gases of the three gas families at the pressures stated in Tables 14 and 15;

• that have a nominal heat input (net CV basis) exceeding 70 kW, but not exceeding 300 kW, including modular boilers ;

• where the temperature of the heat transfer fluid does not exceed 105 °C during normal operation;

• where the maximum operating pressure in the water circuit does not exceed 6 bar.

            -  of the standard type possibly producing condensation in certain circumstances;
  

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