baltur TBG 50 LX PN, Instruction Manual For Installation, Use And Maintenance

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0006081327_201503
ENGLISH
DESCRIPTION OF OPERATIONS
Closing the switch 1, if the thermostats are closed, the voltage
reaches the command and control equipment (led 2 start-up) which
starts operating. Then the fan motor is activated (led 3) in order to
carry out the preventilation of the combustion chamber, at the same
time the servomotor commanding the air shutter is moved to the
opening position corresponding to the set maximum power.
At the end of pre-ventilation phase, the air shutter goes back
to ignition flame position. If the pressure switch controlling the
ventilation air pressure detects an insufficient pressure, the
ignition transformer (led 4) activates and, after 2 seconds, the
main gas and safety valves (led 5) open.
We can specify that:
a) The main valve has a device to proportionally adjust the air/
gas ratio.
b) The safety valve is an ON/OFF type.
c) The air damper is activated by an electric servomotor (see
adjustment 0002933651), remember that when the burner
stops because the thermostat is triggered, the damper is
moved by the servomotor back to its closed position.
Note: The flow rate of gas in the ignition flame position should
generally be greater than the minimum flow modulation. The
ignition flame position can be adjusted using the air shutter
control servomotor (see 0002933651).
The presence of the flame, detected by the control device, permits
continuation and completion of ignition, turning off the ignition
transformer. Then the servomotor opens the air shutter gradually
and the pneumatic valve allows an increase in the gas flow up to
the maximum set value.
If there is no flame, the appliance shuts down in "safety lock-out"
mode (led 7) within 3 seconds from the main valve opening. In
safety lock-out mode the valves are closed again immediately. To
release the appliance from safety lock-out mode, press button 8
on the synoptic panel.
MODULATION OPERATION DESCRIPTION
When the burner is ignited at the minimum setting, if the
modulation probe allows it (adjusted to a temperature or pressure
which is greater than that present in the boiler) the air adjustment
servomotor begins to turn causing a gradual increase in the flow
of combustible air and consequently gas, up to the maximum flow
to which the burner is set. The increase in ventilator air pressure
is detected by the proportional gas valve sensor, which gradually
adjusts the gas flow to the air pressure variation, which is also
gradual. The burner remains in the maximum flow position until the
temperature or pressure are high enough to trip the air regulation
probe, which reverses the rotation of modulation servomotor.
The inverse rotation and therefore the air and gas supply reduction
occurs shortly thereafter. With this procedure, the modulation
system attempts to balance the amount of heat supplied to the
boiler with respect to the amount the boiler releases for use. The
modulation probe installed on the boiler measures any variation
requests and automatically adjusts fuel and combustion air
supply, by starting the air adjustment servomotor and increasing or
reducing rotation as necessary. If the threshold value (temperature
or pressure), to which the complete shut-down device (thermostat
or pressure switch) is set, is reached even with minimum gas
and air output, the burner will be shut down when the device is
triggered.
As temperature or pressure drops below the shut-down device’s
set point, the burner
will be turned on again according to the programme described in
the previous paragraph.
Legend:
1 Main switch on/off
2 Thermostat closing indicator light
3 Fan motor indicator light
4 Ignition transformer indicator light
5 Gas valves indicator
light
7 Lock indicator light
8 Unlocking button
Equipment or
programmer
Safety time Pre-ventilation
time
Pre-ignition Post-ignition Time for
1st flame valve and
2nd flame valve
opening
Air shutter opening
cycle time
Air shutter
closing cycle
time
s s s s s s s
LME 22.331A2 3 30 2 2 11 12 12
LME 22.233A2 3 30 2 2 11 30 30