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BCU 370 · Edition 01.19
24
Function
If there is no pilot burner, program
steps
06
and
07
will be omitted.
As soon as the start-up signal (
ϑ
) is
switched off, post-purge starts. The
butterfly valve moves to the Igni-
tion position during this time, then
to the Closed position. Next, the
BCU rests in the start-up position/
standby.
NOTE: Quick start is not allowed for
units with FM or CSA approval.
H0
05
06
07
08
00
00
H0
01
A1
A0
A2
H8
08
P9
04
03
02
Start-up with
ϑ
signal
Fan run up time t
GV
(P20)
Waiting time t
W
Switch-on delay time t
E
running (P22)
Start-up position/standby
Start-up position/standby
Controlled shut-down
via
ϑ
signal
Flame proving period t
FS1
running for burner/pilot burner (P13)
Butterfly valve moves to Open position
Butterfly valve moves to Closed position
Flame proving period t
FS2
running for main burner (P15)
Safety time t
SA2
running for main burner (P14),
V3 opens
Butterfly valve moves to Ignition position
Controller enabler signal delay time t
RF
(P29)
Controller enable signal
Post-purge time t
PN
running (P19)
If parameter P27 = 0:
V2 is switched off
Safety time t
SA1
running
for burner/pilot burner (P12),
V1 and V2 open
Pre-ignition time t
VZ
running (P21)
Ignition activated