Jun 6, 2010 #1 E egg New member Joined Jul 8, 2008 Messages 9 Reaction score 0 Points 1 My house was inspected and passed for no mold. I have black residue around my floor vents. I have a gas furnace. What is the residue?
My house was inspected and passed for no mold. I have black residue around my floor vents. I have a gas furnace. What is the residue?
Jun 6, 2010 #2 M marko Member Joined May 20, 2008 Messages 52 Reaction score 0 Points 6 Soot from incomplete combustion in the furnace.