BS EN 509-2000 pdf download.Decorative fuel-effect gas appllances.
Any gas cock or tap shall be designed, identified or positioned to avoid inadvertent operation but shall be easy to operate when required. It shall be so designed that the OFF and ON positions are readily distinguishable.
Any gas cock or tap used for the purposes of OFF-ON operation shall be provided with positive stops at the OFF and full ON positions. The gas shall not be shut off in any position of the tap except between the OFF stop and the end of the circumferential seal. For the purpose of this standard any operating mechanism between the control and the tap handle shall be deemed part of the control.
A multi-position tap shall be clearly marked at the ignition position and it shall not be possible to move from the OFF to the ON position without a halt at the ignition position unless the control incorporates another device to avoid a hazard arising. e.g. flame supervision device or ignition cut-out.
Any cock or tap shall be easy to operate at the highest working temperature obtained on the appliance and shall be sound at that temperature.
To indicate the reduced rate position, the tap shall have either a stop at the end of the travel when the reduced rate position is beyond the full-on position, or a positive stop when the reduced rate position is situated between the full-on and the off positions.
The various tap positions shall be marked indelibly and clearly as follows:
Off : disc
ignition burner ignition : stylized star
Full-on (burner) : large stylized flame
Reduced rate : small stylized flame
(if any)
When a single push button controls a safety device that controls both burner and ignition burner, no markings are required if incorrect operation is not possible.
5.2.5 Pressure gol’erllors
Pressure governors shall comply with EN 88: 1991.
An appliance of category 13+ shall not have a governor.
The pressure of appliances of category ‘2E+. and all other categories which have the index ‘E+’ shall not be governed. However. if a gas pressure governor is fitted, it shall not be operational in the range of the two nonnal pressures of the second family pressure couple. i.e. 20 mbar to 25 mbar.
Governors are optional for an appliance in the other categories.
For appliances in categories lI2H3 and “2F+3+. it shall he possible to put the governor, if any. out of service when they are supplied with third family gases. For appliances in category
“2E÷3+ it shall be possible to put the governor partially out of service when they are supplied with second family gases, such that the governor is not operational in the range of the two normal pressures of the second family pressure couple, i.e. 20 rnbar to 25 mbar.
The design and accessibility of the governor shall be such that it can be easily adjusted or put out of service for use with another gas, but precautions shall be taken to make unauthorized interference with the adjustment difficult.
5.2.6 iiult,jiinctional controls
Any multifunctional control shall comply with EN 126: 1995.
5.2.7 Flame supervision devices
I-teat sensitive flame supervision devices of the thermoelectric type shall comply with
EN 125: 1991.
The tiarne detector of an automatic burner control system shall comply with EN 298: 1993. in the event of failure of the means of sensing, the appliance shall be safe.
5.2.8 Shut-off valves
An appliance shall have a device that will allow the gas to the burner and to any ignition burner to be shut ofT as required. Operation of this device may be manual or automatic, but the shut-off shall be effected without delay, for example. it shall not be subject to the inertia time of the safety device. The gas control device, or the assembly of which it is a part, shall be removable.
If an appliance has two separate shut-off devices, one for the burner and one for the ignition burner, the controls for these devices shall be interlocked in such a way that it is impossible for the main burner to be supplied before the ignition burner, On the other hand, if the burner and ignition burner are served by a single shut-off device the ignition burner ignition position shall be indicated by a stop or notch that provides a definite arrest. It shall be possible to operate the shut-off and unlocking device with one hand only.
The gas line shall be fitted with either a thermoelectric device or a valve of class A, B or C to shut off the gas supply to the main burner and ignition burner, if any; the flame detector can operate this valve.
Von-auiornaiic burner svsteni
Appliances shall have a tap or second valve of either class A. B. C or I).
NOTE. The thermoelectric device/main valve and tap/second valve may be either combined or in separate units.
5.2.8.3 Automatic burner system.BS EN 509-2000 pdf download.