29
Displayed
fault code
System characteris-
tics
Cause
Measures
62
Lead break, flow
temperature sen-
sor, assembly 2
Check flow sensor,
assembly 2
63
Lead break, flow
temperature sen-
sor, assembly 3
Check flow sensor,
assembly 2
64
Lead break, DHW
temperature sen-
sor
Check the DHW tempera-
ture sensor
65
Lead break, DHW
return temperature
sensor
Check the DHW return
sensor
90
■ Fuel too damp
■ Lambda probe
inaccurate
■ Logs poorly
charged
■ Use suitable dry fuel
■ Recalibrate Lambda
probe
■ Acknowledge with OK
91
■ Lambda probe
heavily soiled
■ Lambda probe
faulty
■ Electronics fault
■ Recalibrate Lambda
probe
■ Acknowledge with OK
Repair
Fuse (for location, see the connection and wiring diagram on
page 42)
F1
■ 4 A (slow)
■ Power cable KSK
■ 230V 50/60 Hz
Troubleshooting
Fault display
(cont.)
5604 447 GB