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BCU 370 · Edition 01.19
26
Function
If parameter 27 = 0, V2 closes at the
end of the main burner safety time
t
SA2
. The pilot burner is switched off.
Then the flame proving period
for the main burner t
FS2
and the
controller enable signal delay time
t
RF
start to elapse. Afterwards, the
BCU issues the enable signal to the
controller. 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
04
05
06
07
08
00
00
H0
01
A1
A0
A2
03
H8
08
P9
02
Switch on
BCU 370
Start-up with
ϑ
signal
In the event of fault signal: reset
Fan run up time t
GV
(P20)
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)
Safety time t
SA1
running for
burner/pilot burner (P12),
V1 and V2 open
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
Pre-ignition time t
VZ
running (P21d
Ignition activated
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
Waiting time t
W