Furnace shows ignition transformer fault, no spark at burner

Safety: High voltage present. Isolate power and wait before touching ignition components.

• Inspect transformer: Locate the ignition transformer on the Hoval burner. Check for cracks, burn marks, or melted insulation.
• Check HV leads: Follow the high-voltage cables to the ignition electrodes. Ensure they are firmly attached and insulation is intact.
• Check electrode terminals: Tighten the screws or clips holding the leads to the electrodes.
• Test ignition: After reassembly, restore power and observe through the sight glass during start-up. If no spark is visible and the error remains, the transformer or control board requires replacement by a technician.