Common Causes of Blocked Air Ducts

Common Causes of Blocked Air Ducts

Have an HVAC system that’s not doing a great job of keeping your home cool or warm? Most people assume that cooling or heating problems are byproducts of faulty furnaces or air conditioners, but the real issue could be with the air ducts. You can check and see if the ducts are the sources of your issue by turning on the HVAC system, waiting a few minutes, and then holding your hand in front of the vent. Not much air coming out? You probably have a clogged duct (or multiple clogged ducts) on your hands.

But what causes blockages in the HVAC system? And how do you handle blocked ducts? Here are some common causes of blocked air ducts and how to deal with them.

Clogged Filters

Have you been regularly inspecting and changing the air filters? They won’t last forever—over time, they become dirty. Clogged filters are notorious for impeding airflow and causing your HVAC system to disseminate contaminated air throughout the home. For optimal energy-efficiency and air quality, you should be replacing the air filters every 30 to 60 days. The exact frequency varies depending on the type of filter you’re using, so make sure to check the manufacturer’s suggestion for the specific brand you use.

Ductwork Damage

The next most common cause of blocked air ducts is damaged ductwork. If the ductwork becomes disconnected or damaged, air can leak out from the seams. Usually, ductwork damage is simple to repair. In most cases, all you need to do is replace the old duct tape with new duct tape. But if the leak is in a bad spot or if there’s more than one leak, you might need to completely replace the ducts to restore normal airflow.


Two types of physical obstructions can impede the ducts’ ability to function: obstructions outside of the ducts and obstructions inside of the ducts. Start by checking the vents. Is a couch blocking them? You might need to rearrange furniture. Are the vents dusty? It might be time to thoroughly clean them.

If the vents look normal, take a peek inside the ducts themselves. Do you spot any dust, dirt, wood chips, pieces of filters or ductwork insulation, or even insects inside? A professional cleaning can solve the problem in a flash. Looking for Oklahoma air duct cleaning services? Duct Squads uses state-of-the-art equipment and tried-and-true techniques to remove dust, dirt, and other contaminants from your air ducts and return your HVAC system back to normal. Contact us today for more information!