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Appendix A1: RDB BLU Burner Information
A1.3.5 Removal of Control Box
To remove the control box proceed as follows (referring to Figure
A1-2):
•
Unscrew and remove screw (1) and open control box cover
(2).
•
Disconnect all plugs from the control box terminals.
•
Unscrew the retaining finger nut and remove the solenoid coil
(3) from the oil pump.
•
Unscrew and remove the two screws (4) and remove the
control box from the burner.
•
Disconnect the two ignition leads from the ignition
connections on rear of control box.
•
Refit the control box to the burner using the reverse of the
above procedure.
4
4
3
1
2
A1.4 BURNER OPERATION
A1.4.1 Burner Operating Times
Table A1-4:
Burner operating times
Symbol
Description
Value
(seconds)
t0
Standby: the burner is waiting for a heat
request
-
t1
Standby time for an input signal: reaction time,
control box remains in waiting status for t1
≤ 1
t2
Initialisation standby time: check time following
the main power start-up
3.5
t2l
Checks extraneous light during t2: waiting
mode for t2l, then lockout: the motor does not
start
25
t3
Pre-purge time: the fan motor is working
15
t3l
Checks extraneous light during pre-purging:
control box goes into lockout at the end of t3l
25
t3i
Spark pre-ignition time
2
ts
Safety time
5
t4i
Total spark ignition time
10
t4l
Reaction time to achieve safety shut-down due
to flame failure
≤ 1
t5i
Spark post-ignition time
3
tr
Re-cycles: Max. no. 3 repetitions of complete
start-up sequence if there is a flame failure
during
operation; the final action at the last attempt
following flame failure is a lock-out
3 re-cycles
tpp
Post-purge time: additional purge time at the
end of a heat request. Can be interrupted by
a new
heat request
60
A1.4.2 Presence of Extraneous light or Flame
On burner start up, when the fan starts to pre-purge the burner/
boiler, if an extraneous light or flame is detected in the combustion
chamber by the UV sensor the burner fan continues to run until
either:
a)
The extraneous light or flame disappears, or
b) 25 seconds elapses, a burner lockout occurs and the fault
indicator LED flashes Green/RedIf an extraneous light or
flame is detected after the fan has started (i.e. at some
time during the pre-purge period) the pre-purge time of 15
seconds is reset, and the 25 second time for checking for
the presence of extraneous light or flame starts and the fan
continues to run.
As above, if the extraneous light or flame does not disappear after
25 seconds a burner lockout occurs. This function is cumulative
and can operate a maximum of two times during the burner pre-
purge period.
If the extraneous light or flame disappears after 24 seconds (or
less) the pre-purge period and the 25 second countdown for
checking for extraneous light or flame re-starts. If the extraneous
light or flame re-appears the process is repeated. If the
extraneous light or flame appears for a third time, the burner goes
into lockout.
If during a burner recycle operation due to Flame failure (refer to
Section A1.4.4 – Burner Recycle Function) an extraneous light or
flame is detected, the 25 second countdown starts for checking
for extraneous light or flame.
The presence of extraneous light or flame can also be detected
when the burner is in:
a) The standby condition waiting for a heating demand to start
the burner.
b) The Initialisation period (t2) after the heating demand but
before the burner fan starts.
Figure A1-2:
Removal of control box
! WARNING !
Before removing the control box from the burner, or
opening the control box cover, isolate the electrical supply
to the boiler.
