Installation and operating instruction
Gas condensing unit WTC-GB 15-B Compact and WTC-GB 25-B Compact
10 Troubleshooting
83309302 1/2018-05 La
139-196
The following faults must only be rectified by qualified personnel:
Fault
Cause
Rectification
F 66
Calibration could not be carried out
Ensure heat demand.
Subsequent error of
W 22
.
Check the ionisation electrode and cable, replace
if necessary [ch. 9.1.4].
Clean burner surface, if necessary replace
[ch. 9.1.3].
Time until flame formation too long, increase para-
meter
2.3.1 Correction gas quantity
at start
step by step, whilst observing CO
F 67
SCOT base value stored incorrectly
Check gas connection pressure [ch. 7.1.2]
Check setting of
type of gas
.
Carry out calibration via output measurement
[ch. 6.6.7.3].
Reset appliance, replace appliance electronics
WEM-FA-G if occurring repeatedly.
F 68
Gas valve: offset outside of range
Carry out calibration via output measurement
[ch. 6.6.7.3].
Check the ionisation electrode, replace if
necessary [ch. 9.1.4].
Clean burner surface, if necessary replace
[ch. 9.1.3].
Check combustion air for contamination.
Check gas combi valve, if necessary replace.
F 70
Data record error BCC
Carry out
BCC Update
F 71
Data record error BCC missing
Plug in coded plug.
F 72
Data record error BCC
Replace coded plug.
Carry out
BCC Update
F 73
Data record error: BCC not compatible
Check coded plug, if necessary replace.
Carry out
BCC Update
F 74
BCC-Update requested: restart re-
quired
Carry out
BCC Update
F 75
Data record error BCC
Check coded plug, if necessary replace.
Carry out
BCC Update
F 80
Remote control signal (N1) too weak
Check signal [ch. 12.3].
F 81
Remote control signal (N1) too strong
Check signal [ch. 12.3].
F 88
Internal fault
Interrupt the voltage supply temporarily
Reset appliance, replace appliance electronics
WEM-FA-G if occurring repeatedly.
F 90
Communication error ChipCom
Check CAN Bus connection.
F 91
Communication error system device /
burner control
Check CAN Bus connection.
F 92
Communication error CAN
Check CAN Bus connection.
F 93
Communication error Serial Flash
Interrupt the voltage supply temporarily
Replace appliance electronics WEM-FA-G if oc-
curring repeatedly.
F 94
Communication error VPT Modbus
If occurring occasionally:
Requires no action.
If occurring frequently:
Interrupt the voltage supply temporarily
Check multifunction sensor VPT and cable, re-
place if necessary.