Boiler displays A61; burner shuts down unexpectedly during operation

Safety: Gas work must be carried out by a licensed gas technician. Do not attempt to adjust gas valve settings yourself.

• 1. Observe pattern: Note if A61 occurs only at high demand, low demand, or randomly. This helps a technician diagnose gas pressure or modulation issues.
• 2. Check condensate drain: A partially blocked condensate line can cause poor combustion and flame instability. Clean the trap and ensure free flow.
• 3. Inspect burner area: With power and gas off, remove the burner cover and check for heavy soot, rust flakes, or debris on the burner and heat exchanger. Clean as per Buderus service instructions.
• 4. Ionisation electrode: Clean and inspect the ionisation electrode and cable as described for A11. Poor flame detection can mimic flame loss.
• 5. Professional gas checks: A Buderus-trained technician should measure inlet gas pressure, adjust the gas valve if necessary, and verify combustion with a flue gas analyser.