Viessmann Vitodens 333 Service Instructions Manual page 79

Checking and acknowledging faults
Display Const.
fault code
C7 X
Cd X
CE X
CF
dA
db
dd
dE
E4 X
Weat- System
h. character-
comp. istics
X Control
mode,
max. pump
speed
X Control
mode
X Control
mode
X Control
mode
X Control
mode with-
out room
influence
X
X
X
X Burner
blocked
Troubleshooting
(cont.)
Cause Remedy
Communication Check coding
fault – variable
address E5
speed heating cir- settings;
cuit pump, heating check heating
circuit A1 circuit pump
DIP switch
settings
Communication Check Vito-
error Vitocom 100 com 100 and
(KM BUS) connections
Communication Check con-
fault – ext. exten-
nections and
sion coding ad-
dress 2E set-
ting
Communication Replace LON
fault – LON com-
communica-
munication module tion module
Heating circuit A1 Check room
room temperature temperature
sensor –
sensor shorted out
heating cir-
cuit A1
Heating circuit M2 Check room
room temperature temperature
sensor –
sensor shorted out
heating cir-
cuit M2
Heating circuit A1 Check room
room temperature temperature
sensor –
sensor lead break
heating cir-
cuit A1
Heating circuit M2 Check room
room temperature temperature
sensor –
sensor lead break
heating cir-
cuit M2
Fault – supply vol-
Replace con-
tage trol unit
79