Viessmann B1KE Combi Series Installation And Service Instructions Manual page 81

Vitodens 100-W, B1HE/B1KE Combi Installation/Service
Fault Messages Fault Messages Fault Messages
Displayed System characteristics Cause
fault code
F.467 Burner in a fault state
F.468 Burner in a fault state
F.471 No call for heat
No call for heat
F.474 Burner in a fault state
F.527 Burner in a fault state
F.528 Burner in a fault state
F.540 Burner in a fault state
Note: If subscriber faults occur, "Fault, subscriber ..." is
displayed.
(continued) (continued) (continued)
Gas supply insufficient
during calibration.
Contaminated or
insufficiently sized
gas line.
Ionization current too
high during calibration
Lead break or short
circuit
HMU heat
management unit
communication error
Error in scheduled
program run
monitoring
Incorrect parameter
set, HMU heat
management unit
Incorrect parameter
set, BCU burner
control unit
Condensate backup in
the heat cell
Measures
Test static gas pressure and gas flow pressure.

Check that on-site gas line and gas flow switch are

correctly sized.
Visually inspect gas solenoid valve inlet and strainer

on the inlet side for contamination.
Reset the boiler.
Note: Contamination from a brazed gas line, for
example, can block up the gas solenoid valve strainer on
the inlet side.
Check gap between ionization electrode and flame body
assembly.
Check whether there is a lot of dust in the ventilation air
(e.g. from construction work).
Reset the boiler.
Note: Deposits on the electrodes indicate foreign bodies
in the ventilation air.
Check the installation room and flue system for causes
of the deposits.
For example: Laundry detergents, cleaning agents,
toiletries, deposits in the ventilation air supply (chimney)
If flame body assembly and ionization electrode have
been replaced, also clean fan unit, gas/air channel and
Venturi extension.
Check system (plug dD).

Check lead and plug-in connection.

Measure, to see if supply voltage to sensor is 5V–.

Check connecting cable between BCU burner control
unit and HMU heat management unit.
Reset the boiler.
If fault recurs, replace BCU burner control unit:
See page 89.
Overwrite (flash) the HMU heat management unit with
the correct parameter set:
See page 89.
Overwrite (flash) the BCU burner control unit with the
correct parameter set:
See page 89.
Check system for condensate backup.

Check the condensate drain and siphon trap.

Replace insulation blocks, electrodes

and flame body assembly if necessary.
Note: To prevent water damage, detach fan unit before
removing the burner. Protect electronic components
from escaping condensate.
Reset the boiler.
Troubleshooting
81