Boiler locks out with E03, no ignition spark observed

Safety: Disconnect power before touching any ignition components. High voltage is present during ignition.

• Step 1 – Visual inspection of ignition cable: Locate the high-voltage ignition cable running from the control board to the electrode on the burner. Look for burn marks, cracks, or melted insulation. Ensure both ends are firmly seated.
• Step 2 – Inspect ignition electrode: Remove the electrode assembly and check the porcelain insulator for hairline cracks or chips. Replace if damaged. Confirm the tip is not eroded away.
• Step 3 – Check connections at control board: Open the front control panel and locate the ignition output terminals on the Triangle Tube boiler control. Reseat the connector and ensure no corrosion or moisture is present.
• Step 4 – Test operation: Reassemble, restore power and gas, and call for heat. Look through the sight glass for a strong, consistent spark. If there is still no spark and E03 returns, the ignition transformer or control board is likely faulty.
• Professional service: Replacement of the boiler control board or ignition module should be performed by a qualified technician, as gas settings and safety checks are required after repair.