Manual Mode; Manual Mode Limited To 5 Minutes - Honeywell Krom Schroeder BCU 480 Manual

Parameters

4 .8 Manual mode

For convenient setting of the burner or analyzing faults.
The parameter display is not available in Manual mode.
Manual mode can be accessed only if the unit was not
in Fault state before switching off. The following times/
functions are not active in Manual mode: start-up at-
tempts, restart, minimum burner on time and cycle lock.
If the Reset/Information button is pressed for 2 s dur-
ing switch-on, the BCU reverts to Manual mode. Two
dots blink on the display.
In this operating mode, the burner control unit operates
independently of the status of the inputs (apart from
the pre-purge input and the safety interlocks. These are
of higher priority and will be processed first).
Each time after the button is pressed again, the BCU
moves to the next section of the program sequence
and stops there. Briefly pressing the Reset/Information
button (< 1 s) displays the relevant Manual mode step.
When the operating position is reached (program sta-
tus 4 (Operation, pilot burner) or 8 (Operation, main
burner)), the flame signal is indicated instead of the
program parameter after approx. 3 s. If there is flame
simulation during start-up, the flame signal is displayed
immediately.
On units with air valve control, the air valve can be
opened and closed repeatedly by pressing the button
during operation.
BCU 480 · Edition 03.16l
Manual mode can be terminated by switching off the
BCU (On/Off button).

4 .8 .1 Manual mode limited to 5 minutes

Parameter 34
Parameter 34 determines when Manual mode is termi-
nated.
Parameter 34 = 0: Manual mode is not limited in time.
If this function has been selected, operation of the fur-
nace may be continued manually in the event of failure
of the central control system.
Parameter 34 = 1: Manual mode ends automatically
five minutes after the last time the button was pressed.
The BCU then moves abruptly back to start-up position/
standby.
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