C7
Fan or airflow fault
The boiler has detected that the combustion fan is not running correctly or that airflow has not been established.
What this code means
The boiler has detected that the combustion fan is not running correctly or that airflow has not been established.
Possible causes
- Fan fault
- Fan wiring or connector issue
- Airflow or pressure-switch problem
- Control-board fault
Common symptoms
- C7 displayed
- Boiler fails to ignite
- Boiler locks out
Checks to make
- Do not remove the boiler casing
- Arrange diagnosis of the combustion fan and airflow proving system
Safety
- The fan is part of the combustion and flue-safety system. Internal testing must be carried out by qualified personnel.
Model notes
Worcester technical literature maps C7 to fan-not-running/no-airflow conditions.