Usually, a clean cloth dampened with warm water and mild soap (dishwashing detergent, for example) does the trick. Rinsed with clear water and wipe it immediately. If our cooker hood is really very dirty, for a few seconds, send a bit of hot air from a hair dryer on the fat deposits to soften, then passes a paper towel. We finish with mild soap and water.
If our hood is stainless steel, we take care to always clean in the direction of the grain lines (direction of polishing). This type of Hood can also be cleaned using cleaning products specifically designed for this material (from 5$ to 15$, in hardware stores and supermarkets). Avoided however harsh or abrasive household products to avoid damaging the surface. Ditto for painted hoods, because cleaning products chemicals can react to heat and destroy the finish.
As for filters, you can wash the aluminum in the dishwasher, the charcoal must be replaced.
Source : Coup de pouce Magazine, March 2004, translate by Anick Giroux.