Viessmann VITOTRONIC 300 Installation And Service Instructions Manual page 59

Vitotronic 300, GW5B & MW1B Installation and Service
Fault Codes
(continued)
Displayed System
fault code characteristics
C2 Control mode.
CF Control mode.
No communication
via LON.
D3 Control mode.
D5 Boiler ramps to the
electronic maximum
boiler water
temperature limit.
D6 Control mode.
D7 Control mode.
D8 Control mode.
DA Control mode without
room influence.
DB Control mode without
room influence.
DC Control mode without
room influence.
DD Control mode without
room influence.
DE Control mode without
room influence.
DF Control mode without
room influence.
Cause
Lead break, KM
BUS to solar control module or
Vitosolic
Communication fault, LON
communication module of
control unit
Communication fault extension EA1 Check connections (see page 88).
Boiler does not log in at the
cascade control unit
Input DE1 at extension EA1
reports a fault
Input DE2 at extension
EA1 reports a fault
Input DE3 at extension EA1
reports a fault
Short circuit, room temperature
sensor, system circuit A1
(heating circuit 1)
Short circuit, room temperature
sensor, heating circuit with mixing
valve M2 (heating circuit 2)
Short circuit, room temperature
sensor, heating circuit with mixing
valve M3 (heating circuit 3)
Lead break, room temperature
sensor, system circuit A1
(heating circuit 1)
Lead break, room temperature
sensor, heating circuit with mixing
valve M2 (heating circuit 2)
Lead break, room temperature
sensor, heating circuit with mixing
valve M3 (heating circuit 3)
Troubleshooting, Vitotronic 300-K
Measures
Check KM BUS cable and appliance.
Without solar control unit:
Set code "54:0" in the "General" group.
Check LON communication module and
replace if required.
Without extension EA1:
Set code "5B:0" in the "General" group.
Check communication via participant check,
leads/ cables to the Vitotronic 300, GW5B
and codes.
Remove fault at appliance concerned.
Remove fault at appliance concerned.
Remove fault at appliance concerned.
Check the room temperature sensor
(see page 110).
Check the room temperature sensor
(see page 110).
Check the room temperature sensor
(see page 110).
Check room temperature sensor (see page
110) and adjustment of the remote control
(see separate installation and service
instructions).
Check room temperature sensor (see page
110) and adjustment of the remote control
(see separate installation and service
instructions).
Check room temperature sensor (see page
110) and adjustment of the remote control
(see separate installation and service
instructions).
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