BS EN 676:2020 pdf download

BS EN 676:2020 pdf download.Forced draught burners for gaseous fuels.

The documentation of the electrical connectioru for the individual components shall be provided by means of an electrical wiring and connection diagram.
NOTE For burners firing pressurized bodies see Annex K.
4.3.3 Adjustable air damper
Every burner shall be fitted with an adjustable air damper or a similar device [or controlhng the air flow. This device shall be adjustable only by means of a tool. The adjusting positions of the air damper shall be visible, possibly after removal of a cap.
If the burner is provided with a manual means of adjusting the combustion air flow, this means shall be so designed that, after adjustment according to the technical instructions, it is capable of being set and sealed.
4.3.4 Gas line components
4.3.4.1 Genera)
All gas line components downstream the manually operated shut-off valve shall be designed for the supply pressure or be protected against any excessive increase In pressure by means of relevant safety devices.
Requirements for gas line components are described in the relevant product standard such as
F.NHS-1:2011+A1:2016, EN 126:2012. EN 161:2011+A3:2013 and general requirements are given in
EN 13611.
For piping with a pressure > 500 hPa and a pipe diameter DN  25 mm excluding cat. I (see Diagram 6 Annex II PED) Annex K applies.
All gas line components in case of aggressive gases shall be made of materiaLs for appropriate lifetime. The maintenance instructions shall specify periods of service and maintenance and appropriate lifetime or cycles to maintain safety.
4.3.4.2 Manually operated shut•off valve
A quick-acting manually operated shut-off valve shall be provided upstream of all controls to isolate the burner. If this valve Is not supplied with the equipment of the burner, appropriate Information shall be given in the installation instructions, see 6.4.