Performed air duct cleaning and sanitation on a 4 bedroom single system house. All vents and ductwork are clear of dust and debris at this time. System is functioning properly at this time. Recommend duct cleaning every 3-4 years. Performed dryer vent cleaning. Dryer vent, duct, flex hose and lint trap are all clear of lint and debris at this time. Dryer is functioning properly at this time. Recommend dryer vent cleaning every 1-2 years. Thank you for your business!