If your air ducts are dirty, your home usually shows it. Dust blowing from vents, musty smells when the system kicks on, or inconsistent airflow are all early red flags. A spike in allergies, unexplained headaches, or rooms that never feel the right temperature point to clogged or contaminated ducts. If your furnace or AC seems to run nonstop, that’s another sign the system is struggling to push air through the buildup. When these issues show up, a professional duct cleaning isn’t optional it’s overdue.