Technical data

Troubleshooting
84
Diagnosis (continued)
Faults with fault display on the programming unit (continued)
F
a
u
l
t
c
o
d
e
in display
Behaviour of system
Cause of fault Action
c1
Boiler cools down External safety equipment Check connection of plug
aBÖ
Check external safety
equipment (see page 40)
c2
Controlled operation Open circuit
KM-BUS to solar control
Check KM-BUS connection and
solar control. Without solar
control, set coding address
“54: 0”
c4
Controlled operation Fault
Input module 0-10V
Check all connections, cables etc.
Replace function expansion
module; without expansion
module set coding address
“9d: 0”
c8
Boiler cools down Fault
Low water indicator
Check water level of system,
reset low water indicator
c9
Boiler cools down Fault
Maximum pressure limiter
Check system pressure, reset
maximum pressure limiter
ca
Boiler cools down Fault
Minimum pressure limiter or
maximum pressure limiter 2
Check system pressure, reset
minimum or maximum pressure
limiter
cb
Boiler cools down Fault
Additional fixed high limit
Check system pressure, reset
fixed high limit, reset flue gas
damper
cd
Controlled operation Communication fault
Vitocom 300
Check connections and
Vitocom 300
cEe
Controlled operation Communication fault
Plug-in adaptor for external safety
equipment
Check plug-in adaptor for
external safety equipment
cf
Controlled operation Fault
LON communication module
Replace communication module
d1
Boiler cools down Burner fault Check burner
d4
Boiler cools down Fixed high limit has operated Check fixed high limit
d6
Controlled operation Fault at DE1 in the plug-in
adaptor for external safety equipment
Check connection at inputs DE1
to DE3
d7
Controlled operation Fault at DE2 in the plug-in
adaptor for external safety equipment
t
o
D
E
3
d8
Controlled operation Fault at DE3 in the plug-in
adaptor for external safety equipment
da
Controlled operation without
influence of room
temperature
Short circuit
Room temperature sensor, system
circuit A1
Check room temperature sensor
(see page 112)
db
Controlled operation without
influence of room
temperature
Short circuit
Room temperature sensor,
mixing valve circuit M2
Check room temperature sensor
(see page 112)
5285 941 v.1.5