elco Low-NOx N10.12000.30 G-EU2, Руководство по эксплуатации

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Start-up
Fuel-air compound control
Fuel-air compound control
This compound pneumatic control
system with precision-adjustment capa-
bility has been designed to allow the
fuel and air flow rates to be steadily
varied in sliding mode for an adjustment
of the fuel-air ratio over the whole con-
trol range.
In the stepless control mode the load
will be controlled at any point within the
control range depending on the heat
demand.
Electronic compound control
The air flap and the gas flap are each
fitted with a servomotor that controls
the position of these servo components.
At the factory, the air curve of the com-
pound controller is configured in such a
way that the air flap is closed at the
minimum setting and open at the maxi-
mum setting.
As part of burner commissioning, the
servo components for the fuel and air
are assigned permanently defined posi-
tions in relation to burner output. During
burner operation, the servo compo-
nents move into these positions with
great accuracy. This precision is a fun-
damental prerequisite for permanently
ensuring low-emission combustion.
The gas pressure should be corrected
at the gas pressure regulator if neces-
sary.
Please note!
The gas outlet pressure (gas regulating
pressure) must always be less than the
gas inlet pressure but higher than the
total pressure loss of the system.
Proceed in accordance with the com-
missioning instructions for the elec-
tronic compound control system
when making gradual adjustments to
the load points (fuel flow rate, air
flow rate).
Where possible, a combustion meas-
urement should be carried out at each
point.
Equipment option: speed control
The burners can be equipped with a
speed controller as an option.
During long burner operating periods in
the partial load range in particular, the
reduction in blower speed helps to con-
serve electrical energy and reduce
noise emissions from the burner blower
itself.
The speed of the blower is measured
by a Namur sensor
and controlled to the programmed refer-
ence value for the current output level.
Equipment option:
O
2
control / CO control
To improve the efficiency of the system,
the combustion manager can be
equipped with residual oxygen or CO
control (CO control available only with
the use of a Lamtec burner controller).
The residual oxygen is measured in the
flue gas of the heating system by an O
2
measuring probe with zirconium oxide
sensor and sent to the combustion
manager as a correction factor. Thanks
to O2 control, it is possible to eliminate
variations in ambient conditions (e.g.
combustion air temperature and humid-
ity, calorific value fluctuations, etc.) and
significantly reduce the air surplus
required for calibration. Reference
value deviations are controlled by cor-
rections to the blower speed or the air
flap position. With the use of CO control
(only possible with gas operation), the
CO content is measured in addition to
the residual oxygen. The air surplus is
reduced to the “CO edge” by a correc-
tion to the blower speed or the air flap
position. The correction factors are
determined in a system-specific “learn-
ing process” and stored temporarily in
the combustion manager. This makes it
possible to maximise the system's heat-
ing efficiency across the entire output
range and optimally manage the com-
bustion process. For further informa-
tion, please refer to the manufacturer's
documentation for the electronic com-
bustion manager.
1a Gas damper with actuator
1b Air dampers with actuators
2 Burner
3 Boiler
4 Comustion air fan
4
Lu
f t
Gas
1b
1a
3
2
M
M
M
Gas
Air
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