F.352 — Burner in fault state: CO limit exceeded

What does F.352 mean?

The burner is in a fault state because the CO (carbon monoxide) limit within the boiler has been exceeded. This is a critical safety issue indicating improper combustion or flue problems.

• Flue gas recirculation
• Leaks in the flue gas path
• Flue gas back pressure (e.g., water pocket, insufficient fall)
• Constrictions or blockages in the flue gas path

Click steps to track your progress.

1. 1

   Immediately ensure proper ventilation in the area and evacuate if necessary.

2. 2

   Check the entire flue gas path for any signs of recirculation, leaks, blockages, or constrictions.

3. 3

   If any issues are found in the flue system, they must be repaired by a qualified technician. Reset the boiler only after repair.