F.349 — Burner in fault state: Air mass flow rate not correctly detected

What does F.349 mean?

The burner is in a fault state because the air mass flow rate is not being detected correctly in the fan unit. This indicates an issue with airflow measurement or components.

• Dust contamination in the ventilation air
• Contamination of the flame body assembly
• Faulty gas fan unit

Click steps to track your progress.

1. 1

   Check for dust contamination in the ventilation air inlet.

2. 2

   Inspect the flame body assembly for any contamination or debris.

3. 3

   Reset the boiler by briefly turning off and on its power supply. If the fault occurs repeatedly, contact a qualified heating engineer.