baltur BGN 100 DSPGN, Инструкция по эксплуатации

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ELECTRICAL CONNECTIONS
The three-phase or single-phase electric supply line of the minimum section, in proportion to the power absorbed by the
burner, must be equipped with a fused switch. Furthermore, regulations require a switch on the burner’s feed line which
should be located outside the boiler room in an easily accessible position. All electric lines must be protected by
flexible sheaths, be firmly secured and be laid a long way from high temperature parts.
For the electrical connections (line and thermostat) see the relevant diagram.
GENERAL INFORMATION
These burners are of the blown air type which have a mixture of gas/air at the combustion head. They are suitable for
use with combustion chambers which are either raising high pressure or reducing pressure, according to the relative
work curves. Together with excellent flame stability, these burners are safe and highly efficient.
It is equipped with a steel flange which slips on the burner head.
When fastening the burner to the boiler it is necessary to correctly position the flange so that the burner head enters the
combustion chamber to the extent specified by the boiler manufacturer.
DESCRIPTION OF OPERATIONS FOR BGN...DSP GN
(see BT 0002910611 and 0002910640)
This is referred to as a 2-stage progressive operation because the passage from the 1 st flame to the 2 nd flame (from
the minimum rate to the maximum pre-established rate) takes place gradually. The amount of combustion air and fuel
delivery are increased very gradually and this ensures stabilisation of the gas feed network pressure.
The field of variation in flow obtainable is from 1 to 1/3. The burner is fitted with an end-of-the-run switch (a micro-switch)
which stops the burner starting up if the flow regulator is not in the minimum position.
Before ignition, a pre-ventilation of the combustion chamber occurs (according to Regulations) with air open. This lasts
for about 120 seconds. At the end of the ventilation phase, if the air ventilation pressure switch has measured sufficient
pressure, the ignition transformer will be connected and, after four seconds, the ignition flame (pilot) valves and the
safety valve will open. Gas reaches the combustion head, mixes with air supplied by the fan, and is ignited.
Delivery is regulated by the regulator incorporated in the ignition flame (pilot) valve. The ignition transformer is disconnected
two seconds after the ignition flame and safety valves are inserted. The burner is now operating with the ignition flame
(pilot) only. Flame presence is detected by a relative control device (ionisation probe immersed in the flame, or UV Cell).
The relay programmer passes the “shut down” position and gives voltage to the servomotor which regulates the delivery
(gas/air); the burner is now operating at minimum output. If the boiler thermostat (or pressure switch) of the 2nd stage
allows it (regulated at a temperature or pressure value superior to that existing in the boiler), the servomotor which
regulates the gas/air delivery starts turning gradual increase in the gas delivery and in the relative combustion air until
it reaches the maximum delivery value at which the burner has been regulated.
N.B. The “V” cam of the servomotor regulating gas/air delivery (see BT 8562/1) or the “V” cam of the air/gas delivery
regulating servomotor (see drawing n° 0002931170) inserts almost immediately the principle gas valve, which in
turn opens completely. Gas delivery is not determined by the principle valve but by the position of the gas
delivery regulation valve (see BT 8816 BT 8813/1 and drawing n° 0002910060).
The burner remains in the maximum delivery position until the temperature or pressure reaches the limit set for the
intervention of the boiler thermostat (or pressure switch) of the 2nd stage and makes the servomotor regulating gas/air
delivery rotate in the opposite sense of direction. Thus gas delivery and the relative combustion air are gradually
reduced until they reach minimum value. Even with delivery at a minimum, if the limit (temperature or pressure at the
shut down device (thermostat or pressure switch) has been regulated is reached, the burner will be brought to a
standstill.
When the temperature or pressure drops below the intervention limit set on the shut down device, the burner will star up
again, according to the programme previously described. During normal operations, the boiler thermostat (or pressure
switch) of the 2nd stage fitted to the boiler detects the variations requested and automatically proceeds with adapting
the fuel and combustion air delivery by inserting the servomotor which regulates delivery (gas/air). This will rotate in
such a way as to obtain an increase or a decrease. With this manoeuvre, the gas/air delivery regulating system try’s to
equilibrate the quantity of heat supplied to the boiler with that which the boiler gives to be utilised.
If the flame does not appear within two seconds of the opening of the first flame valve (pilot), the control box goes to
“shut down” (the burner stops completely and the relative indicator light is turned on).
To unblock the control box, press the appropriate push-button.