Common Ductwork Obstructions That Can Wreak Havoc on HVAC Efficiency


Heating and cooling bills make up a significant portion of a household budget, and you don’t want to spend any more money on it than you have to. Sometimes, obstructions in your ductwork can negatively affect your HVAC system’s efficiency. Here are some of the most common ductwork obstructions, and what you can do about them.

Dust and Dirt

Dust and dirt are among the most common of ductwork obstructions. Simple household dust, blown-in dirt, and animal dander tend to accumulate in filters and small junctions of your ductwork, blocking air and reducing your home’s air quality. Replacing filters and having your ductwork cleaned when the situation gets bad enough can help address this issue.

Insects and Vermin

Though insects are too small to cause obstructions in most of your ductwork, they can plug up your air conditioner’s condenser drain lines, especially when creepy crawlies such as spiders and ants build nests in the line. If you see visible water collection in the drip pan, your drain line is clogged. You can use compressed air to clear the obstructions. Insects and small animals may also get into your ducts, leaving behind nesting material and other materials that not only impede airflow but also degrade indoor air quality.

Parts of the Ductwork Itself

Sometimes parts of the ductwork itself can cause obstructions. For example, interior duct lining may come loose and hang in the airstream. Careless cable TV installers or DIY enthusiasts often bend ducting, which can also obstruct the airflow. Improperly installed filters can even cause blockages. A trained HVAC professional can tell you if the ducting itself is causing your problems.

Foreign Objects

Foreign objects can also cause obstructions. These objects include a wide variety of materials, from construction materials inadvertently left behind by home builders to small toys dropped into vents by young children.

Signs of Trouble

Sometimes, the only sign you have that there’s trouble with your ductwork is higher energy bills or uneven cooling or heating in certain rooms. If your bills are going up but there’s been no change to your routine, you could have ductwork obstructions. Other signs of trouble include whistling sounds, visible mold growth, foul or rotten odors, and/or respiratory health issues in family members.

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