Microwave emits sparks or arcing inside the cavity during cooking.

Safety: Stop the microwave immediately if you see sparks. Unplug the unit and allow it to cool.

• Step 1 – Remove metal objects: Ensure no metal containers, foil, or twist ties are used. Use only microwave-safe cookware.
• Step 2 – Inspect waveguide cover: Locate the waveguide cover (mica or plastic panel on side/top wall). If it is burnt, cracked, or has holes, replace it with a Bomann-compatible waveguide cover.
• Step 3 – Clean cavity: Thoroughly clean the interior with a non-abrasive cleaner to remove grease and carbonized food, especially near the waveguide and corners.
• Step 4 – Repair chipped paint: If the cavity paint is chipped down to bare metal, sand lightly, clean, and touch up with microwave-safe cavity paint. Allow to cure fully before use.
• Step 5 – Persistent arcing: If arcing continues, the waveguide or magnetron antenna may be damaged and require professional inspection.