Control Box Specifications - baltur BT 40 DSG Manual De Instrucciones

DESCRIPTION OF HOW THE
TWO FLAME BURNERS OPE-
RATE
(see diagram)
The two stage burner always ignites
with a limited amount of air and fuel (1
flame) and, subsequently, after a few
seconds, it will switch to full air and fuel
operation (2 flame). The ignition of the
nd
2 flame is subject to the consent of the
nd
control box and control device (pressure
switch or thermostat). When the burner
works at full rating it will remain in this
position until it reaches the pressure or
temperature limit pre-set on the control
device (pressure switch or thermostat).
The control device trips, disconnecting
the 2 flame (fuel and air), when the limit
nd
to which it has been pre-set is reached.
Then the burner works only with the 1
flame. Normally the 1 flame alone is
st
not sufficient to keep the temperature
or the pressure at the desired limit, and
so it will decrease until it reaches the
limit to which the control device of the
2 flame (pressure switch or thermostat)
nd
reactivates the total fuel and air delivery
rate. If the burner operates only with the
1 flame will stop completely when the
st
pressure or the temperature reaches the
tripping point set on the control device
(pressure switch or thermostat). The
burner starts up automatically again
when the pressure or temperature falls
below the limit to which the pressure
switch or thermostat has been pre-set.
Remarks:
It is inadvisable to oversize the heating
and hot water boiler burner. This is
because the burner may operate in
single-flame mode for long periods, thus
making the boiler operate at a power level
lower than that requested. Consequently,
the products of combustion (fumes)
exit at excessively low temperature
(approximately 180° C for heavy oil
and 10° C for light oil), giving rise to
soot deposits at the chimney outlet.
Moreover, when the boiler is operated at
a power level lower than that indicated
in the technical data it is probable that
Control box and
r elativ programmer
OR /B
LOA 
LAL 1.25
LMO 
acid condensate and soot will form in
the boiler with consequent clogging and
corrosion of the same. This uses only the
burner capacity to ignite at a reduced
output which ensures a smooth lighting
up, an essential condition for boilers
having an over pressure combustion
st
chamber, yet very useful also in normal
boilers (vacuum combustion chamber).
The burner control is subject to the usual
operating and safety thermostats.
Unless prevented by the thermostats
(regulation and safety), tripping the
switch on the burner will power the
control box causing the motor and
ignition transformer to cut in. The motor
sets in motion the following parts:
the fan washing out the combustion
chamber with air, the fuel pump which
circulates fuel through the ducts, venting
any gas through the return. This initial
st
pre-washing phase is terminated when
the solenoid valve (safety and first flame)
opens, sending the fuel at 12 bar to the
nozzle (1 flame nozzle). The latter,
st
then, sends the finely pulverized fuel
into the combustion chamber. As soon
as this pulverized fuel is released from
the nozzle it is ignited by the spark which
has been arcing between the electrodes
since the motor was turned on. When
the first flame is being ignited, the air
gate is kept in the position regulate
by the special screw. This screw is
accessed by removing the plug located
on the upper part of the hydraulic control
piston (see BT 8614, or if a hydraulic
air regulation servomotor is used, BT
8711/1 or BT 865/1).
If the flame is ignited properly, after the
safety period set by the control box, the
solenoid valve for the second flame cuts in
(it is closed when not in use) (if a the air
supply is servomotorized see BT 8711/1
or BT 865/1).
Opening the valve to the 2
allows the diesel fuel, at a pressure of
12 bar, to reach the 2nd nozzle. At the
same time the combustion air regulation
piston moves downward, further opening
the regulator. The piston stroke can
be adjusted using the special screw

Control box specifications

Safety time Preventilation and
in seconds washing time
5
5
5
5
6 / 98
00060807_200709
equipped with locknut. At this point the
burner is in full operation. Once a flame
appears in the combustion chamber, the
burner is controlled by the photoelectric
resistance and by the thermostats. The
control box runs the program and turns
off the ignition transformer. When the
temperature or pressure in the boiler
reaches the set points, the thermostat
or pressure switch will cut in to shut
down the burner. Subsequently, when
the temperature or pressure drops
below a set value, the thermostat or
pressure switch will cause the burner
to cut in once more. If, during operation,
the flame goes out for any reason, the
photoelectric resistance will immediately
cut out (1 second) turning off the power
supply to the relay. This automatically
trips the solenoid valve thus cutting
off flow to the nozzles. At this point the
ignition phase is repeated and, if the
flame lights without difficulty, normal
burner function is restored. If it this is
not the case (if the flame is irregular or
does not ignite at all), the apparatus is
automatically locked out.
If the program is interrupted (by a clack-
out, manual intervention, thermostat trip,
etc.) during the pre-wash phase, the
programmer returns to its initial position
and the entire burner ignition phase is
automatically repeated.
Note:
It is clear from the above that, depending
on the total capacity desired (with
2 nozzles operating), the choice of
nozzle must be made considering a fuel
working pressure of 12 bar. Obviously,
it is possible to change the relationship
between the first and second flame over
a broad range by replacing the nozzle.
One must always recall that for the unit
to operate well, with a single flame the
fuel flow must never drop below the
flame
nd
minimum capacity for the specific model
(which can be read on the label). A lower
flow would make it difficult to ignite the
flame, moreover, in this case, single
flame combustion might not be good.
Post-starting
in seconds
0 5
25 5
22,5 5
25 5
`time between
1st e 2nd flame
5
5 ÷ 8
7,5
5