What Causes Arcing and Sparks Inside a Microwave?
Seeing flashes of bright blue or yellow sparks (arcing) inside your microwave oven while heating food can be alarming. In most cases, arcing is caused by reflective metal particles or a contaminated waveguide cover rather than a catastrophic electrical fault.
1. Damaged or Burnt Waveguide Cover
The waveguide cover is a small rectangular mica sheet located on the right inside wall of the cavity. It protects the magnetron from food splatters. When grease particles bake onto this cover, carbon forms, and microwave energy arcs across the carbon, causing fire flashes.
2. Stray Metal Utensils or Aluminium Foil
Microwave waves induce electric currents in conductive metals. Thin edges, staples on tea bags, gold foil patterns on ceramic plates, or twisted twist-ties cause severe sparking and can crack the glass turntable.
3. Peeling Interior Paint or Chipped Enamel
If the internal protective enamel paint chips away, bare sheet metal is exposed to microwaves. This bare spot becomes a hotspot for electric arcs. Specialty microwave cavity touch-up paint must be applied.
4. Burnt Turntable Roller Ring
Check the plastic roller ring under the glass tray. If food baked onto the wheels has turned black, carbon arcing can occur along the cavity floor.
Book Certified Microwave Oven Service
Do not attempt high-voltage internal repairs yourself. Tru-FIX-IT replaces waveguide mica covers, magnetrons, and touch panels with original parts. Dial 9464881952 for fast doorstep assistance.