Installation and operating instruction
Combustion manager W-FM 100 und W-FM 200
6 Operation
83054802 1/2018-07 La
142-228
6.15 Flue Gas Recirculation
Only the W-FM 200 type LMV52.4… is equipped with the flue gas recirculation
(FGR) function.
Before the flue gas recirculation can be adjusted, burner commissioning with the
FGR damper closed must be carried out.
On burners with separate combustion air fan, the air dampers (Aux2) in front of the
FGR connection housing must also be slightly closed [ch. 6.15.1.2].
The FGR function is fuel specific and must be set separately for each fuel on dual
fuel burners.
If the FGR function is only used for one fuel on dual fuel burners, the actuator posi-
tion (Aux3) for the other fuel must be set to 0° (closed) in all load points and spe-
cial positions.
6.15.1 FGR function
6.15.1.1 Fan on burner
Through a pipeline, the fan draws the flue gas from the flue gas pipe. A flue gas
damper (FGR damper)
1
in the pipeline meters the recirculated flue gas quantity.
The FGR damper is driven load dependent, in compound by the actuator (Aux3).
The recirculated flue gas quantity dependents on the position of the FGR
damper
1
, the negative pressure in the air regulator
2
and the flue gas pressure at
the extraction point
5
. With sufficient negative pressure the FGR damper operates
up to an opening angle of approx. 60° … 70°, above this the recirculated flue gas
quantity increases marginally. If the recirculated flue gas quantity is insufficient to
reach the NO
X
content, the negative pressure in the air regulator has to be in-
creased, to do this either:
close air damper
3
further,
increase speed
4
.
The air quantity required for combustion must not be changed, to achieve this al-
ternately change the actuator position and speed.
Summary of Contents for W-FM 100
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