baltur 17530020, Instruction Manual For Installation, Use And Maintenance

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MODULATION OPERATION DESCRIPTION
Blown air burners with electronic modulation may be used on hearths
under strong pressure or in a vacuum, according to the corresponding
operating curves.
They combine a very stable flame with total safety and high
performance.
The burner is fitted with an electronic cam controlled by a microprocessor
for intermittent operation, and for the control and monitoring of the
blown air gas burners.
The burner is fitted with a valve tightness control device. To better
understand the operation of the electronic cam, read the specific
instructions in the manual provided carefully.
Electronic modulation is achieved by means of two step (air/gas)
regulation motors.
The definition two-stage progressive operation means that transition
from the first to the second status is progressive in terms of both
amount of combustion air let in and amount of fuel, offering significant
benefits for the stability of the gas mains pressure.
Ignition is preceded by the combustion chamber pre-ventilation, as set
forth by the standards, with air open and with a duration of approx. 30
seconds.
If the air pressure switch has detected a sufficient pressure, the ignition
transformer activates at the end of the pre-ventilation phase and after 3
seconds the safety and main valves open in sequence.
Gas reaches the combustion head, mixes with air supplied by the fan
and is ignited. The gas supply is regulated by the butterfly gas valve.
Three seconds after the valves (main and safety) come on, the ignition
transformer goes off. Thus the burner is ignited at the ignition point.
The presence of the flame is detected by the control device (ionisation
probe immersed in the flame).
The programmer relay moves past the locking position and sends
voltage to the air/gas supply adjustment servomotors, which go to the
minimum point (200).
If the second stage boiler thermostat or pressure switch allow it (set to
a temperature or pressure value higher than the existing value in the
boiler), the air and gas supply regulation servomotors will start to turn,
gradually increasing the supply up to the maximum output to which the
burner has been set.
CAUTION / WARNINGS
The electronic cam controls the burner, activating the combustion
air, gas servomotor and the fan motor, if the inverter is fitted,
according to a curve that has ten points set (see curve regulation
table).
The burner remains in the maximum output position as long as the
temperature or pressure reaches a value sufficient enough to cause
the intervention of the probe that rotates the gas/air flow rate regulation
servomotors. This progressively reduces the gas, combustion air and
motor's RPM (if the inverter is fitted) to the minimum.
If the threshold value of temperature or pressure to which the control
device is set is reached, the burner will be shut down.
As temperature or pressure drops below the control device set-point,
the burner is started again as described above.
During normal operation, the modulation probe installed on the boiler
measures any variation in temperature or pressure and automatically
adjusts the fuel and combustion air flow rate through the relevant
servomotors.
In this way the burner is able to optimise the request of heat to be
supplied to the boiler.
If the flame does not appear within 3 seconds after the gas valves have
opened, the control box goes into the lock-out condition (the burner
shuts down completely and the warning light turns on).
To “reset” the control box operation, press the reset button.
A
B
farfalla_gas_TBGME
A Graduated scale.
B Gas throttle valve position reference index.
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