Boiler controller displays E01 and burner will not start; no flame established.

Safety first: Isolate electrical power to the Danstoker boiler at the main disconnect and close the fuel shutoff valve (gas or oil) before opening any burner panels. Allow the boiler to cool.

Step-by-step checks:

• Reset the burner control: Locate the burner control box (e.g., Siemens LME, LMV, or similar) on the Danstoker burner assembly. Press the reset button once and observe if the burner attempts ignition. Do not reset more than 2–3 times without inspection.
• Inspect ignition electrodes: Remove the burner front cover. Check the ignition electrodes for cracks, carbon buildup, or damage. Clean with fine emery cloth and ensure the ceramic is intact. Verify the electrode gap and position according to the burner manufacturer’s specification (often 3–4 mm gap, centered in the fuel spray or gas stream).
• Check ignition transformer / ignition cable: Inspect the ignition transformer (or high-voltage ignition module) and its cables for burn marks, loose connections, or insulation damage. Tighten terminals and replace damaged cables. If there is no spark during ignition trial, the transformer may be faulty.
• Verify flame sensor: For ionization rods, clean the rod with fine abrasive pad and ensure it is properly immersed in the flame zone. For UV cells, clean the viewing window and ensure no soot or oil film is blocking the sensor. Check wiring back to the burner control.
• Fuel supply check: Confirm that the main gas valve or oil shutoff valve is open and that any Danstoker-installed safety shutoff valves (SSOVs) are energized during ignition. Check for tripped low gas pressure switch or oil pump issues.

When to call a technician: If E01 persists after cleaning and basic checks, a certified burner technician should test ignition voltage, flame signal strength, and combustion settings, and may need to replace the ignition transformer, electrodes, or flame sensor.