BS EN 525:2009 pdf download
BS EN 525:2009 pdf download.Non-domestic direct gas-fired forced convection air heaters for space heating not exceeding a net heat input of 300 kW.
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b) a removable air-break electrical link other than a disconnection of the electrical winng in the electrical supply to the main gas automatic shut-off valves or the main gas control function within an automatic shut-off valve; or
c) an air-break switch requinng the use of a tool for its operation to isolate the electrical supply to the main gas automatic shut-off valves or the main gas control function within an automatic shut-aft valve: or
d) an air-break switch not requiring the use of a tool for its operation to isolate the electrical supply to the main gas automatic shut-off valves or the main gas control function within an automatic shut-off valve.
In this particular case. where the main gas valve(s) is/are fitted with a closed position indicator switch, or a proof of closure switch, then the switch shall be checked for correct position throughout the first safety time and subsequent period of main gas isolation. Failure to prove correct positioning shall cause safety shut-down.
NOTE I A multituncuonal control incorporating the facility required by a) is deemed to meet the requirement
NOTE 2 AddItional clrcu4ry over and above that provided by the control box may be necessary to satisfy requirement d).
NOTE 3 Designers should be aware that the intention of this requirement is to prevent inadvertent release of the main gas supply at all times that the commissioning engineer is sening or checking the start gas flame.
The appliance shall be provided with such manual valves as are essential for the normal operation and commissioning of the appliance
Means shall be provided for checking the gas soundness of automatic shut-off valves.
Means shall be provided for checking the regulator inlet and outlet pressures and the bumer manifold pressure,
Connections or test points shall be provided for the measurement of the flame detector signal.
Test points shall be provided to facilitate the measurement of differential air pressure across the bumer and/or
profile plate.
513 AddItional requIrements for appliances designed for permanent outdoor Installation
513.1 General
Appkances designed for permanent outdoor installation shall be so constructed that they are fully protected against the rigours of the environmental conditions under which they are expected to operate,
5.132 Air inlets
Air Inlets shall be provided such that their lowest edge Is at least 500 mm above the base of the appliance, or
will reach 500 mm above floor level when installed In accordance with the manufacturers Instructions. &13.3 Access panels and doors
Access panels and doors and such insulation as needs to be removed during normal servicing shall be so designed that repeated removal and replacement does not damage the insulation or impair the waterproofing of the appliance.
5.13.4 DimensIons of openIngs
No dimension of any opening (eg. electrical wiring points) from the inside of the appliance to the outside air shall permit the entry of a ball of diameter 16 mm applied with a force of 5 N.
6 Operational requirements
6.1 Soundness of the gas circuit
The gas circuit shall be sound.
External soundness is assixed if, under the conditions specified in 7.3.1, the air leakage rate does not exceed
100 crn% regardless of the number of vaNes fitted in series or in parallel on the appliance.
6.2 Heat inputs
6.2.1 Nominal heat Input
When measured under the conditions specified in 7.3.2.2, the heat input obtained at normal pressure shall be
within ± 5 % of the nominal heat input.
6.2.2 Start gas heat Input
When measured under the conditions specified ii 7.3.2.3. the start gas heat Input obtained at normal pressure shall be within ± 5 % of the start gas heat input declared by th manufacturer where the injector has a diameter greater than 0.5 mm.
Where the injector diameter is 0,5 mm or less the start gas heat input shall be withii *10 % of the manufacturer’s declared value,
6.2.3 Effectiveness of gas rate adjusters
For an appliance without a gas regulator but with a gas rate adjuster, the heat input obtained after adjustment of the device:
a) shall be not less than the nominal heat input, under the conditions given ii Test 1 of 7.3.2.4;
b) shall not exceed the nominal heat input under the condibons given In Test 2 of 7.3.2.4.
