Viessmann VITODENS 333 Service Instructions Manual page 78

Troubleshooting
Checking and acknowledging faults
Fault code Const.
in the dis-
play
bC
bd
bE
bF
C2 X
C5 X
78
Weat- System
h. character-
comp. istics
X Control
mode with-
out remote
control
X Control
mode with-
out remote
control
X Control
mode
X Control
mode
X Control
mode
X Control
mode,
max. pump
speed
(cont.)
Cause Remedy
Communication Check con-
fault - Vitotrol nections,
remote control cable, coding
heating circuit A1 address A0
and the
remote con-
trol DIP
switches
Communication
fault - Vitotrol
remote control
heating circuit M2
Vitotrol remote Check the
control incorrectly DIP switch
encoded settings of
the remote
control
Incorrect LON com- Replace the
munication module LON commu-
nication mod-
ule
Communication Check con-
fault - solar control nections and
unit coding
address 54.
Communication Check coding
error - variable address 30
speed internal settings;
pump check the
heating cir-
cuit pump
DIP switch
settings.