baltur 67340010, Инструкция по установке, использованию и обслуживанию, Страница: 72 / 96

OPERATION DESCRIPTION WITH GASEOUS
FUEL
The burner operates fully automatically: it is activated by switching on
the main switch and the control panel switch.
Burner operation is managed by command and control electronic de -
vices.
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 perfor -
mance.
The burner is fitted with an electronic cam controlled by a microproces -
sor 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 in -
structions in the manual provided carefully.
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 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.
Flame presence is detected by the dedicated control device (UV pho -
tocell).
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.
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 ser -
vomotors.
In this way the burner is able to optimise the request of heat to be
supplied to the boiler.
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0006160318_202106
ENGLISH