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A blocked HVAC duct can wreak havoc on both you and your home. For example, if a block occurs during the winter months, some (or all) of the rooms in your home may not receive heat, thus making them uninhabitable. Understanding the most common causes of blocked ducts can help you pinpoint the problem and find a solution. You may also be able to use this knowledge to prevent trouble in the first place.

How to Check for a Blocked HVAC Duct
Since a blocked HVAC duct can share symptoms with a variety of other issues, it’s important to take immediate action to determine what you’re up against. Here are three questions to answer:

  • Are you experiencing air flow in some parts of your home but not others?
  • Does the temperature vary greatly from room to room?
  • Have you noticed a recent increase in your energy bill?

If you answered yes to one or more of these questions, there’s a chance you have a blocked duct. It’s at that point that you can do the following[i]:

Turn on the air conditioning or heat: Once it’s on, check the vents throughout your home for airflow. Make note of any rooms that are getting no air or a limited supply.

Inspect your furnace filter: Not only are you checking for a clogged filter, but you’re also checking to see if it’s properly installed. If it’s been a while since you last changed it, every duct may appear to have a block. That’s because the air flows through your filter before the rest of your home.

Check at the vents: You won’t be able to see the entire duct, but upon reviewing the cover you can use a flashlight to take a closer look. You never know what you’ll find in the ductwork, ranging from construction debris to child toys. If you spot something, take caution in removing it.

Inspect the ductwork from the outside: You won’t be able to see areas that are covered by drywall, so head to your basement and attic for a closer look. You could find everything from a hole in the duct to missing duct tape to something that’s impaled it and requires removal.

Inspect the dampers: Dampers are common with multi-zone HVAC systems, with these opening and closing to control airflow to specific parts of the home. If a damper is not opening and closing as designed, it can block air from reaching its destination.

As a roundup, common causes of blocked HVAC ducts can include but are not limited to:

  • Clogged furnace filter
  • Improperly installed furnace filter
  • An object(s) in the duct
  • Damaged ductwork
  • A malfunctioning damper

Each one of these problems has its own solution, some of which are easier to tackle than others.
For example, it’s easier to replace a furnace filter than it is to repair damaged ductwork behind a wall or swap out a bad damper.

Fortunately, even if you’re facing a challenge, there’s a solution to every problem. And if you require professional help, don’t hesitate to contact us. We can visit your home, pinpoint the cause of your block, and talk to you about the best solution.

DIY Air Conditioning

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