What does the Vaillant ecoTEC exclusive F23 fault code mean?
The F23 fault code indicates a flame failure in the Vaillant ecoTEC exclusive boiler. This means that the boiler is unable to detect a flame during the ignition process, which can prevent it from operating correctly.
Common Causes
- Blocked Flue: A blockage in the flue system can prevent proper ventilation, leading to flame failure.
- Faulty Flame Sensor: If the flame sensor is dirty or malfunctioning, it may not detect the flame, causing the boiler to shut down.
Can I fix it myself? (DIY)
It is advisable to call a Gas Safe Engineer for issues related to gas and electrical components. Attempting to fix these problems without proper training can be dangerous.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F23 fault could be around £150 to £250, primarily depending on whether the flame sensor needs cleaning or replacement, which is a common issue.