What does the Baxi Duo-tec F25 fault code mean?
The F25 fault code on a Baxi Duo-tec boiler indicates an ignition failure, meaning the boiler is unable to ignite the gas to produce heat. This can prevent the heating and hot water systems from functioning properly.
Common Causes
- Blocked Flue: A blockage in the flue system can prevent the safe expulsion of combustion gases, leading to ignition failure.
- Faulty Ignition Electrode: If the ignition electrode is damaged or malfunctioning, it may not create the necessary spark 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 gas appliances can be dangerous. However, you can check the boiler pressure and reset the boiler if it is low or has locked out.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving an F25 fault could be around £150 to £250, depending on whether the issue is a simple reset or requires replacement parts like the ignition electrode.