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Identifying Dirty Air Ducts

While your heating, ventilation, and cooling (HVAC) system delivers hot and cold air throughout your home, it also works hard to produce clean air––but this is only possible if you keep your home’s ductwork intact. If your HVAC system is struggling, consider checking for dirty air ducts.

Check For Dirty Air Ducts

If your allergies are acting up or your home’s air smells a bit off, you may be dealing with dirty air ducts. Inspecting your ductwork can be tricky, but there are a few steps you can take to see if dirty air ducts are the cause of your HVAC issues.

How To Check For Dirty Air Ducts

  • Do you notice dust building up on the surfaces within your home even though you clean frequently? If your ducts are dirty or leaking, you will also notice more dust in the air or on surfaces after your furnace turns on.

  • We focus on the cleanliness of the surfaces that our food comes in contact with but what about the air that we breathe? If you're getting an odor when your system is running it could be dirty ductwork. Bacteria, microbial growth, and dirt inside of your ductwork can become airborne and lead to odors when your HVAC system turns on.

  • Find the filter in your HVAC system. For most systems, it will be next to your furnace on the return side (where the air comes into the system). Depending how your system is oriented, it could also be below the furnace. If you need to remove an access panel to reach the filter, make sure to shut your HVAC system off first.

    Once you've found it, note the direction of the airflow arrow marked on the filter and pull it out. If the filter looks grey, it's time to change it. You may even be able to see the dirt and dust buildup on the filter. Another basic test is to hold the filter up to a light source. If you cannot see light through the filter then air cannot pass through the filter either. Standard 1" thick air filters should be replaced at 2 month intervals under normal operating conditions. Media air filters are 4"-5" thick and should be checked at 6 months, if OK continue using it for no more than 1 year.

    CAUTION: Always turn the power to your furnace off if you need to remove panels or handle parts inside the furnace.

  • If your filter is clean or the odour and dust continue after changing it, the issue is likely in your ductwork. Having your ductwork inspected for cleanliness, air sealing, insulation, and damage should be done when purchasing a home or prior to selling your home or if the airflow doesn't seem right all of a sudden. It is also good practice to have this inspection performed during planned maintenance visits. Since the technician will already be checking the inside of the equipment he can also check the inside surfaces of the ductwork. Recommendations can be presented and planned for some time in the future.

Dealing with dirty air ducts? If not, consider other issues for why your HVAC system is struggling.

What To Do If You Have Dirty Air Ducts?

When you have dirty air ducts, it’s best to hire an HVAC technician to thoroughly inspect and clean your ductwork. Scheduling regular maintenance for your ductwork can help keep your air clean, your respiratory system healthy, and prolong the lifespan of your HVAC system.

Want to learn more? Connect with one of our Remote Assist technicians to help troubleshoot any issues with your heating and cooling system.

NOTE: This content is for informational purposes only, and HomeX and its affiliates disclaim all liability related to it. If you decide to perform any tasks based on this information, you assume all risks, including the risk of loss or damage to property or personal injury.

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