How often should HVAC air duct cleaning be done?- HVAC Ducts should be inspected every two years and the air handler annually. Cleaning frequencies vary greatly due to many factors. When was the last time you had your system serviced? Whether you just purchased a new home or if you can’t remember the last time you had someone take a look at your system call Daffy Ducts today. “We’re Crazy About Quality” Schedule Now