Boiler display shows E6 and burner will not ignite, often after several failed attempts

Critical safety warning: Repeated ignition attempts can lead to unburned gas accumulation. If the boiler has tried to start multiple times, wait several minutes before retrying and ensure the area is well ventilated.

• Observe ignition sequence: After a reset, watch through the sight glass (if provided). Confirm if you see a spark at the igniter and if gas is being delivered.
• Inspect igniter: With power and gas off, remove the igniter assembly. Check for cracks in the ceramic insulator and carbon buildup on the electrodes. Clean lightly and verify the gap matches Pennco specifications (typically around 1/8"–3/16").
• Check grounding: Ensure the burner assembly and control board ground wires are securely attached to clean metal surfaces.
• Reinstall and test: Reassemble the burner and attempt a restart. If there is still no flame and E6 returns, the ignition transformer or integrated control may be faulty.
• Do not repeatedly reset: If lockout persists, contact a qualified technician to test the ignition circuit and gas valve.