Viessmann B0KA Installation And Service Instructions Manual page 61

Fault messages
(cont.)
Displayed fault System characteristics
code
92 Function of the relevant elec-
tronics module in emergency
mode
95 Burner off
100 Electronics modules connec-
ted to PlusBus not function-
ing
102 No internet connection
103 Normal operation
104 Depending on configuration
of EM-EA1 extension (DIO
electronics module)
142 Burner in a fault state
160 Burner in a fault state
161 Burner in a fault state
Cause
ADIO electronics module
communication error
OpenTherm remote con-
trol unit not connected
Voltage error PlusBus
Error with communication
module
Internal communication
error, programming unit
External fault message in-
put active
Communication restriction
on CAN bus INR
Communication error,
CAN bus
HBMU heat management
unit data memory access
fault
Troubleshooting
Measures
Check setting in the commission-
■
ing assistant and correct if re-
quired.
Check connections and leads to
■
the ADIO electronics module.
Check PlusBus voltage level
■
(24 to 28 V).
Check subscriber number on ro-
■
tary switch S1 and correct if re-
quired.
Check connection to the Open-
■
Therm remote control. unit.
If OpenTherm is not required, set
■
C.7 in the commissioning assis-
tant to a value other than 14.
Check whether the PlusBus power
supply on the HBMU heat manage-
ment unit is OK: Remove all con-
nected PlusBus components and
reconnect one by one.
Check that no more than 1
Vitotrol 200-E is connected to the
HBMU.
Check whether there is a short cir-
cuit at the PlusBus cable.
Check cables and plug-in connec-
tions between heat management
unit and communication module.
Check cables and plug-in connec-
tions between heat management
unit and HMI programming unit.
Check connected external device.
Check the fan unit for correct func-
tion. For this, check the stepper
motor of the fan unit (reference run
with mains ON).
If the fault persists, check the plug-
in connections and cables of the
CAN bus.
Check further CAN bus subscrib-
ers. If fault occurs repeatedly, re-
place fan unit.
Check connections to CAN bus
subscribers (INR, HBMU).
Check connections to external
CAN bus subscribers.
Reset the appliance.
If the fault occurs repeatedly, re-
place the HBMU heat management
unit. See chapter "Replacing the
HBMU heat management unit".
61