Performed air duct cleaning and sanitation on a 2 system 4 bedroom house. All vent and ductwork are clear of dust and debris at this time. Both systems are functioning properly at this time. Recommend air 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! Customer is interested in having 2 returns installed in the ceiling for the upstairs system. She will be contacting the office in the next few weeks.