Air conditioner blows small gray particles November 02, 2011, 12:24:42 pm Yahoo Message Number: 126327My Dometic Brisk Air Duo-Therm air conditioner has recently started blowing out small dark gray particles. It happens both when cooling and when using the heat strip. Replacing the filter didn't help, and the old filter was in good shape (not disintegrating). I phoned Dometic customer service, but the person I talked to didn't know what it was. The unit is from 2003. The particles vary in size up to about 1 square millimeter. They're dry and leave no residue.Any ideas?
Re: Air conditioner blows small gray particles Reply #1 – November 02, 2011, 02:31:48 pm Yahoo Message Number: 126331More than likely they are dust particles that have gotten past the inlet filter and built up on the fan blades. When built up enough (takes several years) they will break loose from the blades (and other surfaces in the airway) and blow out. When I had this problem with a past coach, I took the cover off the roof AC section, uncovered the fan housing and wiped each blade plus vacuuming all areas in the airway. Maybe a new filter element a little larger might help after the cleaning. Mike