The appearance of soot, or black discoloration on the walls around electric wall heaters, is not caused by the heater itself. Sooting is caused by other things in the environment such as burning candles, cooking, cleaning supplies, manufactured fireplace logs, pets, and even plants. Airborne particles from these items get into the heater and partially burn to a carbon material, which adheres to walls, under pictures, and on carpets or drapes.
What causes heater sooting?
20- 06- 2017