C6
Fan speed fault
The boiler has detected combustion-fan speed outside the expected range.
What this code means
The boiler has detected combustion-fan speed outside the expected range.
Possible causes
- Fan running too fast or too slow
- Fan control or wiring fault
- Control-board issue
Common symptoms
- C6 displayed
- Boiler may fail to ignite or lock out
Checks to make
- Do not access internal components
- Arrange qualified diagnosis of the fan, wiring and control system
Safety
- Combustion fan faults can affect safe flue operation. Service should be carried out by qualified heating personnel.
Model notes
Worcester technical literature maps C6 to fan-speed conditions.