Troubleshooting
103
Diagnosis
(continued)
Faults with fault display on the programming unit
(continued)
Fault
code in
display
Behaviour of system
Cause of fault
Action
c4
Control mode
Faulty communication with Input
Module
0 to 10 V
Check connections and
cables/leads; replace Input
Module, if required
(see page 126)
Without Input Module:
Set coding 9d: 0
c8
Boiler cools down
Error
Low water indicator
Check water level of system,
reset low water indicator
c9
Boiler cools down
Error
Maximum pressure limiter
Check system pressure, reset
maximum pressure limiter
ca
Boiler cools down
Error
Minimum pressure limiter or
maximum pressure limiter 2
Check system pressure, reset
minimum or maximum pressure
limiter
cb
Boiler cools down
Error
Additional fixed high limit or limit
thermostat or flue gas damper
Check system pressure, reset
fixed high limit or flue gas
damper
cd
Controlled operation
Communication error
Vitocom
Check connections and
Vitocom
cEe
Controlled operation
Communication error
Plug-in adaptor for external
safety equipment
cf
Controlled operation
Error
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 reset to
25
°
C (+/- 5.0
°
C)
Cooler than the high limit set
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
d8
Controlled operation
Fault at ”DE3” in the plug-in
adaptor for external safety
equipment
e0
Controlled operation
Open circuit
LON communication module
Check connection
5
3
5
1
3
3
8
v
1
.8