Viessmann VITOTRONIC 300 GW2 Installation And Service Instructions Manual page 85

Diagnosis
(continued)
Faults with fault display on the programming unit (continued)
Fault code
Behaviour of system
in display
Controlled operation without
dc
influence of room temperature
Controlled operation without
dd
influence of room temperature
Controlled operation without
de
influence of room temperature
Controlled operation without
df
influence of room temperature
Controlled operation
e0
Retrieving fault codes from the fault memory (fault history)
1 2 3 4 5 6 7
Cause of fault
Short circuit
Room temperature sensor,
mixing valve circuit M3
Open circuit
Room temperature sensor,
system circuit A1
Open circuit
Room temperature sensor,
mixing valve circuit M2
Open circuit
Room temperature sensor,
mixing valve circuit M3
Open circuit
LON communication module
All faults which have occurred are stored and can be retrieved by scanning.
The scanning sequence starts with the most recently stored fault code.
1. Press and simultaneously for
approx. 2 seconds.
2. Access the individual fault codes by
pressing the or
Sequence of Fault code
stored fault
codes
Last (most recent)
1
fault code
. . . .
. .
Last fault code but
10
nine
3. Press .
Action
Check room temperature sensor
(see page 112)
Check room temperature sensor
(see page 112)
Check room temperature sensor
(see page 112)
Check room temperature sensor
(see page 112)
Check connection
(see page 96)
Scanning of fault history is
activated.
All stored fault codes can be
button. deleted by pressing
Scanning of fault history is
terminated.
Troubleshooting
.
85