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F.29

Ignition unsuccessful after flame loss

F.29 means the flame was lost during operation and the subsequent ignition attempt was unsuccessful.

What this code means

F.29 means the flame was lost during operation and the subsequent ignition attempt was unsuccessful.

Possible causes

  • Interrupted gas supply or insufficient gas pressure
  • Flue-gas recirculation or blockage
  • Poor electrical earthing
  • Blocked condensate discharge pipe
  • Control-electrode issue

Common symptoms

  • Boiler stops after previously firing
  • Heating or hot water is lost
  • F.29 displayed

Checks to make

  1. Check whether other gas appliances are working
  2. Check pre-payment meter credit if applicable
  3. In freezing weather, safely inspect an external condensate pipe for freezing
  4. Arrange professional diagnosis if the fault remains

Safety

  • Do not remove the boiler casing or work on internal gas, combustion, flue or electrical components unless appropriately qualified.

Model notes

A persistent F.29 requires proper diagnosis rather than repeated resets.