Bosch Condens 7000 FP - Page 59

Operating and fault displays
59
Condens 7000 FP – 6721846699 (2022/12)
B 6A 577 No flame detected
within the safety
time.
Ionisation current
< 1.1 µA during safety
time.
Air in gas line.
Excessively high flue system
backpressure due to unfavourable
layout (too many deflections; cross-
section inadequate or too long;
horizontal sections too long).
Inadequately sized gas line cross-
sections (min. cross-section of the
gas supply pipe)
The gas pressure regulator is not
appropriate for the required gas
volume.
Gas supply pressure too low.
Check whether the plug-in connector
for the compensation/ionisation line
is correctly installed.
Check the connecting lead between
the burner control unit and the
monitoring electrode for poor
contacts, breaks and damage.
Check the connecting lead between
the ignition transformer and ignition
electrode for poor contacts (on
electrode and transformer), breaks
and damage.
Check electrode gaps and ignition/
monitoring electrode for damage.
Ignition/monitoring electrode dirty.
Ignition transformer faulty (no
ignition spark or delayed ignition
spark, "hard start").
Burner control unit defective.
 Venting the gas line.
 Install properly dimensioned and
configured flue system.
 Install adequately dimensioned
gas lines.
 Install a gas pressure governor
that is appropriate for the
required gas volume and, if
necessary, notify the gas
supplier.
 If pressure too low, inform gas
company.
 Establish good electrical contact.
Replace cables if necessary.
 Align burner rod or electrode.
Replace defective electrode.
 Clean or replace ignition/
monitoring electrode.
 Replace ignition transformer.
 Replace burner control unit.
V 6A 578 No flame detected
within the safety
time.
No flame signal was
detected during the
safety time.
Flue gas and/or supply
air route blocked.
Interlock following 3rd
attempt.
If the service code is still displayed,
check the temperature switch
(Chapter 15).
 Replace the temperature switch
if required.
V 6C 576 Ionisation current
> 0.9 µA during
preventilation.
No flame signal was
detected within the
preventilation phase.
Electrode dirty or faulty.  Clean the electrode and, if
necessary, replace it.
If replacing the electrode does
not resolve the issue, the burner
control unit must be replaced.
B 6L 514 Loss of flame
during the flame
stabilization
period.
No flame signal was
detected within the
flame stabilization
period.
-  None, the burner control unit
tries to start again.
B 6L 515 Loss of ionisation
signal when boiler
is running.
Ionisation signal is lost
when the burner is in
operation.
-  None, the burner control unit
tries to start again.
V 6L 561 5 power-up
sequences (power
supply
disconnection
during burner
start).
The burner control unit
was switched off 5
times during the burner
start.
Check the 230 V power supply to the
control unit.
 Reset the burner control unit at
the reset button.
 Rectify power supply problem.
Type
1)
Fault
code
Sub
code
Cause Description Test procedure/Cause Action