Ducts that are so dirty can be quite difficult to efficiently clean, and the best option may be to replace them. With proper maintenance, no, there is no need to clean the air ducts. Instead, your local HVAC company should seal or replace the ductwork. If you have dirty ducts, you have a problem somewhere that needs to be found.
Your HVAC unit is designed to last 12 to 17 years if properly maintained, so if you're nearing the end of your unit's lifespan, it's time to replace it. It seems like a logical maintenance activity, but cleaning the air ducts in your home's air conditioning system may not be as good an idea as It seems.
