BS EN 303-3:1999

Heating boilers. Gas-fired central heating boilers. Assembly comprising a boiler body and a forced draught burner | Status: Current

1 Scope 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 standard boilers and low-temperature boilers with a nominal heat output not exceeding 1 000 kW and with a water temperature at normal operation not exceeding 105 °C. This European Standard does not contain all the necessary requirements for:

• — assemblies designed as units;
• — condensing 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 (see 3.6). 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. Text deleted This European Standard only covers type testing.