I have a Harman P43 and the glass gets the light brown residue on it after use of about 8 hrs. run time. Does your unit with the air wash system do any better or is this about the best I can expect? Doesn't often get the dark brown to black residue but that could be because my wife doesn't like the residue accumulation and shuts it down to clean the glass almost every day. Currently using Stove Chow pellets but will be switching to Lignetics in about a week.
MERRY CHRISTMAS
MERRY CHRISTMAS