Boiler will not ignite and displays E001 on the control panel

Safety first: Turn off power to the boiler at the service switch and close the gas shutoff valve before removing any covers. If you smell gas, evacuate and contact your gas supplier or a licensed technician immediately.

• Step 1 – Reset and observe: Restore power, open the gas valve, and attempt a reset from the front control panel. Watch through the sight glass for sparking and flame. If E001 returns, continue.
• Step 2 – Check gas supply: Verify the external gas shutoff is fully open. Confirm other gas appliances in the home work. If they do not, the issue may be with the building gas supply, not the boiler.
• Step 3 – Inspect ignition electrode: With power and gas off, remove the front cover. Locate the ignition electrode assembly near the burner. Check for cracked porcelain, heavy carbon buildup, or loose wiring. Clean light deposits with a non‑metallic abrasive pad and ensure the electrode gap and position match Navien specifications (refer to service manual).
• Step 4 – Check flame rod: Inspect the flame rod (flame sensor) for oxidation or soot. Gently clean with fine steel wool or emery cloth and wipe with a clean dry cloth. Reinstall firmly.
• Step 5 – Inspect wiring and ground: Confirm all connectors from the main PCB to the gas valve, ignition transformer, and flame rod are fully seated. Verify the boiler has a solid earth ground connection.
• Step 6 – Gas valve and pressure: Only a qualified technician should connect a manometer to the gas valve test port to verify inlet and manifold pressure. If pressures are out of spec or the valve does not open when commanded, the gas valve assembly or PCB may need replacement.

If E001 persists after cleaning and basic checks, contact a Navien‑authorized technician for combustion analysis and component testing.