Kromschroder BCU 465, Technical Information

Page: 29 / 31

29
T-Product · BCU 465 · 2006 April
? At start-up – flame verified
visually, display flashes and in-
dicates 02 or 03 ?
• Read flame signal (parameter
01); if it is lower than the switch-
off threshold (parameter 04), this
may be attributable to the follow-
ing causes:
! The set value for the switch-off
sensitivity is too high.
! Short-circuit on the ionization
electrode as the result of soot,
dirt or moisture on the insulator.
! Ionization electrode not correctly
positioned at the flame edge.
!
Gas/air ratio incorrect.
! Flame not contacting burner
ground as the result of exces-
sively high gas or air pressure.
! Burner or BCU not (adequately)
grounded.
! Short-circuit or discontinuity on
the flame signal cable.
! Soiled UV sensor.
• Correct fault.
? The display flashes and indi-
cates 30 ?
! Abnormal data change in the pa-
rameters set for the BCU.
• Reset the adjustable parameters
to their original values using
BC-Soft or remove the unit and
return it to the manufacturer for
inspection.
• Make sure that you meet require-
ments in chapter “System De-
sign Information”
? The display flashes and indi-
cates 31 ?
!
The unit has suffered an internal
unit fault.
• Make sure that you meet require-
ments in chapter “System De-
sign Information”
• Remove the unit and return it to
the manufacturer for inspection.
? The display flashes and indi-
cates 32 ?
! The supply voltage of the unit is
below the rated voltage.
• Ensure correct voltage supply
(maximum ratings are given in
the technical data).
? The display flashes and indi-
cates 51 ?
! Safety interlocks have disconti-
nuity, no voltage at terminal #5.
• Check safety interlocks.
! Short-circuit at ignition or valve
output.
• Check wiring and fine-wire fuse
F1 (3.15 A, slow-blow, H, to IEC
127-2/5).
• If this does not correct the fault,
the BCU must be returned to the
manufacturer for inspection.
Checking the safety function
• Close the manual valve.
• Start the burner control unit
frequently and check the safety
function simultaneously.
• If the operation is incorrect, re-
turn the BCU to the manufac-
turer.
WARNING! If this function
check is not carried out, the
gas valves might remain open
allowing non-combusted gas
to escape. Explosion risk!
Troubleshooting
Fault codes (?), Possible Causes (!) and Solutions ( • )