Description Of Working - baltur TBL 85P Manuel D'instructions Pour L'utilisation

DESCRIPTION OF WORKING

It is not advisable to have too large a burner for the boiler for heating and
for hot water as the burner may work for long periods with a single flame,
making the boiler work at lower than required output; as a result of this
the combustion products (fumes) emerge at too low a temperature (at
about 180° C in the case of heavy oil and 130° C with light oil), causing
soot to build up at the flue. In addition, when the boiler is working at
lower output than that indicated in the technical data, it is likely that acidic
condensate and soot will form in the boiler with the result that it will quickly
corrode and get clogged up. When the two-flame burner is installed on
a hot water boiler for heating use, it must be connected so that it works
normally with both flames, completely stopping without passing to the
first flame when the preset temperature is reached. So that it works in
this way, do not install the second flame's thermostat, and make a direct
bridge connection between the equipment's terminals. In this way only
the burner's capacity to switch on at low rate is used for a gentle ignition,
which is essential for boilers with a pressurised combustion chamber and
also very useful for normal boilers with depression combustion chamber.
The boiler's start - stop is subject to the usual running or safety
thermostats.
By switching off switch 1, if the thermostats are closed, the voltage
reaches the command and control equipment (switching on Led 2) which
starts it working. The fan motor (LED 3) and the ignition transformer (LED
4) are then switched on. The motor turns the fan that carries out an air
wash of the combustion chamber and at the same time of the fuel pump
that cause circulation in the ducts that expels any gas bubbles through
the return valve. This pre-wash stage ends with the opening of the safety
solenoid valves and the first flame (LED 5), which allows the fuel at a
pressure of 12 bar to get to the first flame's nozzle and from this to enter
the combustion chamber finely atomised. As soon as the vaporized fuel
leaves the nozzle it is lit by the charge between the electrodes on the
start of the motor. During first flame ignition the air damper is kept in
the position registered on the screw which is accessed by unscrewing
the cap on the top of the hydraulic control piston (see page 39), if the
air adjustment servo motor is used (see page 46). If the flame appears
normally, with the safety time set by the electrical equipment passed,
this switches on the solenoid valve (closed at rest) of the second flame
(LED 6) (if the air adjustment servo motor is used, see page 46). The
opening of the 2nd flame allows the light oil, at a pressure of 12 bar, to
reach the 2nd nozzle and, at the same time, the control piston for the
combustion air adjuster moves down to open the adjuster further. The
travel distance of the piston can be registered with the screw with locking
nut, the burner is thus working at full rate. From when the flame appears
in the combustion chamber the burner is controlled by the photoelectric
cell and the thermostats.
The control equipment follows the program and switches the ignition
transformer off. When the temperature or the pressure in the boiler
reaches that set by the thermostat or pressure switch, the latter stops
the burner. Subsequently, when the temperature or the pressure falls
below the closing level of that of the thermostat or pressure switch, the
burner is switched back on again. If, for any reason, during the working
of the burner the flame is lost, after just one second the photoelectric cell
reacts to cut off the power supply from that relay to automatically switch
off the solenoid valves which intercepts the nozzles flow. The switch on
stage is thus repeated and, if the flame ignites again normally, the burner
starts working again normally, if not (if the flame is irregular or fails to
light completely) the equipment goes automatically into lock-out (LED 7).
The LMO44 device goes into lock-out after three
!
repetitions of the ignition cycle.
If the program is interrupted (due to a power supply failure, manual action
or the intervention of the thermostat, etc.) during the pre-wash stage,
the programmer returns to its starting position and will automatically
repeat the whole of the burner ignition sequence.
It is clear from the above that the choice of nozzles, depending
!
on the total capacity (2 nozzles working) desired, must be
made taking into account the capacity corresponding to the
working pressure of 12 bar using light oil. It is of course
possible to vary within wide limits the relationship between
the first and the second flames by replacing the nozzles.
Bear in mid however that for good working, the fuel supply with the first
flame should not be less than the minimum capacity (as indicated on the
plate) for the specific model. A lower capacity will make ignition difficult
and combustion with the first flame alone may not be good.
1 Main ON-OFF switch
2 Live voltage light
3 Fan working light
4 Transformer on light
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5 2 stage working light
nd
6 1 stage working light
st
7 Control box lock-out light
8 Control box release button