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BCU 460, BCU 465 · Edition 11.19
33
Air control
4 Air control
A central protective system such as the FCU 500 takes
over air control. It monitors the static air pressure as
well as the air volume required for pre-purge, start-up
and after the furnace has been shut down. The air actu-
ators (BCU with LM..F1 = actuator IC 40, BCU with LM..
F3 = valve) are actuated for this purpose by the capacity
control system of the BCU.
After being enabled by the protective system, the BCU
can start the burners. The capacity is controlled during
operation by an external temperature control system.
VAS
M
PZL
PZH
PZ
PZL
PDZ
TE
M
FCU 500..F0
µC
P
DG
DG
DG
VAS
VAS
VCG
VCG
VR..L
VR..L
DG
DG
DG
min
DG
max
49
15
13
14
50
45
47 48
58
>750°
p
u
/2
DL
min
DL
Purge
BCU/LM..F3
BCU/LM..F3
ϑ
1
46
2
3
PZL
PDZ
M
FCU 500
µC
P
DG
DG
49
15
13
14
50
45
>750°
1
46
2
3
DL
min
DL
Purge
BCU/LM..F3
BCU/LM..F3