Viessmann VITOTRONIC 100 GC1 Installation And Service Instructions Manual page 102

Troubleshooting
Diagnosis
(continued)
Faults with fault display on the programming unit (continued)
Fault
Behaviour of system
code in
display
aa Controlled operation
ab Controlled operation, DHW tank
may be cold
aC c
Controlled operation
aC d
Controlled operation
b0 Controlled operation
b1 Controlled operation
b4 Emissions test mode
b5
Controlled operation
b6 Operation at constant temperature
b7
Boiler controlled on basis of
adjustable high limit
b8 Controlled operation
bf Controlled operation
c1 Boiler cools down
102
Cause of fault
Therm-Control configuration
error:
plug aJA of
Therm-Control temperature
sensor not inserted
DHW heating
configuration error:
Coding "55: 3" is set, but
plug aJB is not inserted
and/or
coding "4C: 1" and "4E: 1"
not set
Return temperature sensor
configuration error:
Coding "0C: 1" is set, but
plug aJA is not inserted
and/or
coding "4E: 0" is not set
Butterfly valve
configuration error:
Coding "0C: 2", "0C: 3" or
"0C: 4" is set,
and
coding "4E: 1" is set
Short circuit
Flue gas temperature sensor
Communication error
Programming unit
Internal fault
Internal fault
Invalid hardware code
Internal fault
Boiler coding card
Open circuit
Flue gas temperature sensor
Incorrect LON communication
module
External safety equipment
Action
Insert plug aJA
On Vitocrossal:
Check that coding "0d: 0" is set.
Insert plug aJB and check coding
Insert plug aJA and check coding
If butterfly valve is installed:
Set coding "4E: 0"
If no butterfly valve is installed:
Set coding "0C: 0" or "0C: 1"
Check flue gas temperature sensor
(see page 53)
Check connections, if necessary
replace programming unit
Check electronics board
Check electronics board
Check the control software circuit
board and confirm the coding address:
- Enter coding 2 (see page 117
for instructions).
- Change code 8A to 176.
- Confirm coding 92:160
Insert boiler coding card or replace
if defective (see page 42)
Check flue gas temperature sensor
(see page 53)
Replace LON communication
module
Check connection of plug
aBÖ
Check external safety
equipment