What does the Worcester Bosch Greenstar CDi F23 fault code mean?
The F23 fault code indicates a flame failure in the Worcester Bosch Greenstar CDi boiler. This means that the boiler is unable to detect a flame during the ignition process, which can prevent it from operating properly.
Common Causes
- Blocked Flue: A blockage in the flue system can prevent exhaust gases from escaping, leading to a flame failure.
- Faulty Ignition Electrode: If the ignition electrode is damaged or dirty, it may not create a spark to ignite the gas.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for any gas-related issues, including flame failures. Attempting to fix gas appliances without proper training can be dangerous.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F23 fault could be around £150 to £250, depending on whether the issue is a blocked flue or a faulty ignition electrode that needs replacement.