baltur 35575410, Instruction Manual For Installation, Use And Maintenance

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OPERATING DESCRIPTION
When the two-stage burner is installed on a boiler for the production of
hot water for heating purposes, it must be connected so it can operate
under normal conditions with both flames, completely stopping, without
operating with single-stage, when the predefined temperature is
reached.
To obtain this operating condition, do not install the second stage
thermostat and make a direct connection (bridge) between the
respective equipment terminals.
Thereby only the burner's capacity for ignition at a reduced flow rate
will be used for a soft start, which is an essential condition for boilers
with pressurized and vacuum combustion chambers.
The burner's command (on or off) is dependent on the operating or
safety thermostats.
Closing the main switch and the ON / OFF switch of the electric panel,
if the thermostats are closed, the voltage reaches the command and
control equipment which starts operating.
This switches on the fan motor and the ignition transformer.
The fan motor starts fan rotation, which performs a wash with air in the
combustion chamber and, at the same time, the pump makes the fuel
circulate in the pipes, expelling any air bubbles through the return line.
This pre-washing phase ends with the opening of the safety solenoid
valve and the 1st stage, making it possible for the fuel to reach the
1st stage nozzle at a pressure of 12 bar and exit in the combustion
chamber finely atomized.
The fuel atomised by the nozzle is set on fire by the spark present
between the electrodes as soon as the motor starts.
During first stage ignition, the combustion air delivery is determined
by the adjustment of the control hydraulic jack, see the chapter on the
jack.
If an air regulation servomotor is used, see the 1st stage cam
adjustment in the chapter on servomotor cam adjustment.
If the flame appears in a normal manner, once the safety time foreseen
by the control box has passed, it activates the 2nd stage solenoid valve
(closed, in stand-by).
If an air regulation servomotor is used, see the 2st stage cam
adjustment in the chapter on servomotor cam adjustment.
**NT**
At the same time, the piston that controls the combustion air regulator,
moves downward opening further the regulator.
The piston stroke can be adjusted by turning the screw with the lock
nut, see the chapter on the jack.
In this way the burner is fully operational.
Since the flame appears in the combustion chamber, the burner is
controlled by photoresistors and thermostats.
The control equipment follows the program and switches the ignition
transformer off.
When the temperature or pressure in the boiler reaches the value to
which the thermostat or pressure switch is calibrated, the burner stops.
Vice versa if the temperature or pressure descends below the
calibration values of boiler's thermostat or pressure switch, the burner
restarts.
If during the operation the flame is interrupted for at least a second, the
photoresistor activates and cuts out the power supply to the relay, thus
closing the fuel shut-off solenoids.
The ignition phase is repeated in this manner and, if the flame reignites
normally, the burner will return to normal operation. Otherwise the
equipment will shut-down automatically.
If the program is interrupted, due to a power supply failure, manual
action or the intervention of the thermostat, during the pre-wash stage,
the programmer returns to its starting position and automatically
repeats the entire burner ignition sequence.
IMPORTANT
The LMO 44 device goes into lock-out after three repetitions of
the ignition cycle.
IMPORTANT
The selection of the nozzles depending on the total flow rate (2
nozzles in operation) must be made accounting for the flow rate
values that correspond to the fuel operating pressure of 12 bar.
It is possible to vary widely the ratio between the first and second
stage by replacing the nozzles.
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