We Recommend getting your air duct cleaned every 2-3 years. Frequency of cleaning depends on several factors.
The air ducts of HVAC systems collect contaminants such as allergens, bacteria, dust particles, fungi, and other lovely things you don’t want to be breathing in or having clog up your system.
A professional crew will need 2-5 hours on average to clean a system’s air ducts. The system’s complexity can make that time vary, though, and a technician will be able to make a more precise assessment after inspecting the system