F.29 — Failure during operation: Re-ignition unsuccessful

What does F.29 mean?

The boiler's flame extinguished during operation, and it failed to re-ignite. This results in the boiler shutting down for safety.

• Temporary interruption in the gas supply.
• Flue gas recirculation, where exhaust gases are drawn back into the combustion chamber.
• Condensate duct is blocked.
• Faulty earthing of the boiler or the ignition transformer is failing to produce a spark.

Click steps to track your progress.

1. 1

   Ensure your gas supply is stable and not interrupted.

2. 2

   Check the condensate pipe for any blockages, especially during cold weather.

3. 3

   Press the fault clearance key on the boiler to reset it. If the fault persists, contact Vaillant Service Solutions.