Troubleshooting - Wolf CGB-75 Installation And Technical Manual

Any faults will be displayed as fault codes by Wolf controllers with eBUS capability. To these faults, cause and remedy may be
allocated using the following table. This table is designed to allow your local heating contractor to trace the fault more easily.
Fault Fault
code
1 TBV excess temperature
Water pressure too low
4 No flame established
5 Flame failure during
operation
6 TW excess temperature
7 TBA excess temperature
Overpressure
in the flue gas system
11 Flame pretence
12 Faulty flow sensor
Gas pressure too low
14 Cylinder sensor faulty
15 Faulty outside
temperature sensor
16 Return sensor faulty
20 Fault, gas valve "1"
21 Fault, gas valve "2"
24 Gas fan fault
25 Gas fan fault
26 Gas fan fault
30 CRC fault, gas
condensing boiler
31 CRC fault burner
32 Fault in 24 V AC supply
33 CRC fault, default values
34 CRC fault, BCC
60

Troubleshooting

Cause
The flow temperature has exceeded the limit
for the TBV shutdown temperature, or the
heat exchanger is extremely dirty, or the water
pressure switch switches off at a pressure < 1.0 bar
No flame established during burner start
Flame failure within 15 s after
flame recognition
The flow/return temperature has exceeded the limit for
the TW shutdown temperature
The flue gas temperature has exceeded the
limit for the TBA shutdown temperature
Flue gas system is blocked
Ventilation air is blocked
A flame is recognised before the burner starts
The sensor for the flow temperature or the cable is
faulty, or the
gas pressure < than the selected value at the gas
governor (only displayed after 15 min)
DHW temperature sensor or lead faulty
The outside temperature sensor or lead is faulty
The return temperature sensor or lead is faulty
A flame is recognised for 15 seconds after burner
operation, even though gas valve 1 has received a
shutdown command
A flame is recognised for 15 seconds after burner
operation, even though gas valve 2 has received a
shutdown command
The gas fan does not reach the required pre-purging
speed
The gas fan does not reach the ignition speed
The gas fan does not stop
The EEPROM record "Gas condensing boiler" is invalid Switch the power supply OFF and ON
The EEPROM record "Burner" is invalid
24 V AC supply outside the permissible range
(e.g. short circuit)
The EEPROM record "Master reset" is invalid
Faulty boiler coding card
Remedy
Check system pressure; check heating
circuit pump; vent the system; press reset
button; clean heat exchanger; check TB
combustion chamber; increase system
pressure; check dirt filter
Check gas supply line, open gas tap if
necessary
Check ignition electrode and ignition cable
Press reset button
Check CO values
2
Check ionisation electrode and cable
Press reset button
Check the system pressure. Vent the system
Set the pump to stage 2 or 3
Clean the heat exchanger
Check the flue gas system
Check the ventilation air
Press reset
Check lead
Check flow sensor
Check gas pressure
Check gas governor (accessory)
Check sensor and lead
Check lead
Check outside temperature sensor
Check lead
Check return sensor
Replace the gas combination valve
Replace the gas combination valve
Check the gas fan supply cable and the gas
fan. Press reset
Check the gas fan supply cable and the gas
fan. Press reset
Check the gas fan supply cable and the gas
fan. Press reset
If unsuccessful, replace the control unit PCB
Switch the power supply OFF and ON
If unsuccessful, replace the control unit PCB
Check gas fan
Replace the control unit PCB
Replace boiler coding card
30 62 555_0709