baltur BT 250 DSG 4T, Manual User Instructions

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0006160029_201305
ENGLISH
OPERATION DESCRIPTION
(NO. 0002904060)
Closing the main switch on the equipment (1) if the thermostats
(regulation and safety) permit it, the current reaches the electric
control equipment that starts the motor and the ignition transformer,
after a few seconds the motor causes the fan to rotate to preventilate
the combustion chamber with air, at the same time the pump
circulates the diesel in the ducts. During the pre-ventilation phase,
the motor that activates the combustion air gate opens it to the
second flame position (pre-ventilation with open air).
Then, the air shutter is returned to the first flame position for ignition.
This "pre-washing" and "pre-ventilation" phase is complete when
the solenoid valve (7) closes (open in the stand-by phase).
After the solenoid valve is closed, the pressure increases in the
delivery ducts, the fuel arrives at the 1st stage nozzle at a pressure
of 16 bar to which the pump is calibrated and device no. 4 opens
that is located in the spray nozzle unit The safety solenoid valves
(9) and (10) are electrically connected in series and open when the
solenoid valve (7) closes.
Coil voltage is therefore 115V with 230V mains voltage.
The directional arrow of the electromagnetic valve (10) must be
turned to the nozzle, which means that the electromagnetic valve
on nozzle return is mounted opposite to the flow (during burner
operation).
The atomised diesel exits the nozzle and set on fire by the spark of
the electrodes already present when the motor starts. If the flame
appears regularly, the programmer passes the lock position and
starts the motor that activates the combustion air gate, moving it
to the second stage position. During this manoeuvre, a specific
adjustable cam, activated by the same motor as the gate, closes
and electric contact that directs current to the solenoid valve (8) that
is closed during the stand-by phase.
The opening of the 2
nd
stage valve makes it possible for the fuel, at
a pressure of 16 bar, to reach the 2
nd
stage nozzle closure devices
no. 4/1. The pressure acts on the 2
nd
stage nozzle closure device
that, up to a pressure of 12 bar, prevents the fuel from flowing to the
second nozzle. The pressure of 16 bar now acts on two nozzles.
The safety oil pressure switch (10) set to 5 bar, checks the pressure
on the return, an excessive pressure increase switches the burner
off.
The selection of the nozzles in function of the desired total flow rate
(2 nozzles in operation) must be made accounting for the flow rate
values that correspond to the operating pressure of 16 bar. It must be
kept in mind that when a burner is operating with only the first stage,
the fuel delivery corresponds to only a nozzle at a pressure of 16 bar.
It is obviously possible to vary the ratio between the first and second
stage within the wide limits by replacing the nozzles. Keep in mind
that in order to ensure proper operation, fuel delivery with the
first stage must not be lower than the minimum flow rate (located
on the burner model data plate). A lower flow rate could make
ignition difficult and combustion with only the first stage may not be
satisfactory. These burner models use three nozzles; in this case
there are two second stage nozzles and both are subjected to a
pressure of 16 bar.
Once the flame appears in the combustion chamber, the burner
is commanded and controlled by the photoresistors and by the
thermostats. When the temperature or pressure reaches the value
to which the operating thermostat or pressure switch is calibrated,
its intervention will cause the burner to stop.
The equipment resumes operation automatically as the temperature
or pressure value has reduced its value by the necessary amount. If
for any reason the flame goes out during operation, the photoresistor
will intervene immediately (one second) that will stop the feed
from the corresponding relay and open, and therefore deactivate,
the washing solenoid valve (7) that, when opening, will quickly
release the existing pressure and the spray of atomized diesel will
be stopped by the automatic closure of the spray nozzle unit valve
closure devices as soon as the pressure goes below the value to
which they are set. The burner has a switch (3) on the mimic panel
for switching from stage 1 to stage 2.
1 Main switch ON - OFF
2 Appliance unlock button
3 1
ST
/2
ND
stage switch
4 Auxiliary safety fuse
5 Transformer ON led
6 1st stage LED
7 2nd stage LED
8 Fan LED
9 Power LED
10 Appliance shutdown LED