EVS-EN 303-3:1999

This European Standard specifies the requirements and test methods for the construction, the safety and the rational energy usage of an assembly made up of a boiler body complying with EN 303- 11) and a forced draught gas burner complying with EN 676, using combustible gases, hereafter referred to as a "boiler". This European Standard applies to a boiler:  - with a nominal output not exceeding 1 000 kW.  This European Standard does not contain all the necessary requirements for:  - assemblies designed as units;  - condensing boilers and low temperature boilers;  - boilers intended to be installed in the open;  - boilers permanently fitted with more than one flue outlet;  - boilers fitted with a draught diverter;  -  boilers intended to be connected to a common flue having mechanical    extraction. This European Standard does not apply to living-space dedicated boilers. If the boiler body has already been tested with a liquid fuel burner, in accordance with EN 303-1, EN 303-2 and EN 304, only the tests described in annex G need to be performed. In the case of a range of boilers, see annex F. This European Standard does not contain all the necessary requirements for low temperature boilers. Nevertheless, the testing methods defined by this European Standard for the determination of useful efficiencies can be used for low temperature boilers, after being adapted in accordance with annex H. This European Standard only covers type testing.