What does the Vaillant ecoTEC pro F25 fault code mean?
The F25 fault code on the Vaillant ecoTEC pro indicates an ignition failure, meaning the boiler is unable to ignite the gas to start the heating process. This can lead to a lack of hot water and heating in your home.
Common Causes
- Blocked Flue: A blockage in the flue can prevent proper ventilation, leading to ignition issues.
- Faulty Ignition Electrode: If the ignition electrode is damaged or malfunctioning, it may not create the spark needed to ignite the gas.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for any gas or electrical issues, as working on these systems can be dangerous. However, you can check the boiler pressure and reset the boiler if necessary.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving an F25 fault could be around £150 to £250, primarily depending on whether the ignition electrode needs replacement or if the flue requires clearing.