Viessmann VITODENS 111-W Installation And Service Instructions Manual page 75

Fault messages
(cont.)
Displayed fault System characteristics
code
102 No internet connection
103 Normal operation
104 Depending on configuration
of EM-EA1 extension (DIO
electronics module)
142 Burner in a fault state
161 Burner in a fault state
162 Burner in a fault state
163 Burner in a fault state
176 Burner in a fault state
182 No DHW heating
183 No DHW heating
Cause
Error with communication
module
Internal communication
error, programming unit
External fault message in-
put active
Communication restriction
on CAN bus. INR.
HBMU heat management
unit data memory access
fault
Processor low voltage
Checksum error, data
memory access, HBMU
heat management unit
Condensate backup in the
heat cell
Short circuit, outlet tem-
perature sensor (if instal-
led)
Lead break, outlet temper-
ature sensor (if installed)
Troubleshooting
Measures
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.
Reset the appliance.
If the fault re-occurs, replace the
HBMU heat management unit: See
chapter "Replacing the HBMU heat
management unit".
Reset the appliance.
If the fault re-occurs, replace the
HBMU heat management unit: See
chapter "Replacing the HBMU heat
management unit".
Reset the appliance.
If the fault re-occurs, replace the
HBMU heat management unit: See
chapter "Replacing the HBMU heat
management unit".
Remove condensate backup.
Replace insulation blocks, electro-
des and burner gauze assembly.
Note
Remove the fan unit before open-
ing the burner. Protect the PCB
from water damage.
Check outlet temperature sensor
(plug X7, cores 3 and 4). Measure
sensor input on HBMU heat man-
agement unit. Set value: 3.3 V
with sensor disconnected.
Check outlet temperature sensor
(plug X7, cores 3 and 4).
75