Furnace shows A06, attempts to start but shuts down quickly, sometimes with visible spark but no stable flame

Safety: Turn off power and gas before working on ignition components.

• Check electrode position: Remove the burner cover and visually inspect the ignition electrode. Compare its position and gap to the Beretta service manual diagram. If bent, carefully realign so the spark occurs directly in the gas stream at the burner port.
• Clean burner head: Remove the burner assembly if accessible. Brush off rust and debris from the burner head and ports. Use compressed air to clear small holes. Reinstall correctly, ensuring gaskets are intact.
• Inspect ignition cable: Look for cracks or burn marks on the high-voltage cable from the control board to the electrode. Replace if damaged.
• Reset and test: Restore power and gas, reset the lockout, and observe ignition through the sight glass. If there is no spark at all, the ignition transformer or control board may be defective and should be replaced by a technician.