Product review (2 stars): This unit is very noisy
Perhaps it is unique to this range hood I bought or not, my unit when I turn on the fan it not only vibrate the hood portion but also the whole wall and I could hear the noise even upstairs. At this point, the source of the noise is due to unbalance in the circular fan which is one piece. I see no marking as to if the factory has ever adjusted the balance. I am afraid if I ask for a relacement I'd get the same out of balance fan again. At point I have not contacted the manufacturer yet but i will.  If anybody wants to buy this product be aware that the fan can be out of balance  causing a lot of noise thus vibration.
Also I feel the air coming from somewhere right on my forehead, indicating there is a gap that air is leaking out on to your direction if you stand in front of it.