Harold Kestenholz
In a sense, yes, Jim. The radiators heat the air creating air movement local to the radiator, so it carries air to the area of the radiator more concentratedly than to other locations. It doesn’t have to be soot, though the suggestion to check for abnormal amounts in the air is well taken.
fourthyear is correct about it being a common problem to any air moving device including baseboard, radiators and air registers.
