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Identifying A Dirty Furnace Filter

Is your furnace on the fritz? If you’re noticing lower efficiency or reduced airflow from your furnace, there’s likely something wrong with one of its interior parts––and sometimes it can be as simple as a dirty furnace filter.

Check For A Dirty Furnace Filter

When your heat is on, dust and other particles in your home’s air pass through your ducts and furnace. Before reaching your furnace, the filter catches larger particles like hair and dirt to allow for cleaner air to move through your system. Over time, these particles can collect on your filter and strain your system.

How To Check For A Dirty Furnace Filter

  • Check the airflow from your vents. Does it seem like there's less air moving than there used to be? Restricted airflow is a sign that buildup on your filter might be blocking the free movement of air in your system.

  • Locate your furnace or air handler. Filters will always be on the return side (where the air flows into the unit). Typically, they are immediately beside, above, or below the furnace or air handler itself. In some cases, you may need to remove an access panel to see it. If you do need to remove a panel, ensure the system is turned off beforehand.

    If you can't find the filter anywhere around the unit itself, check behind the return air grills in your home. There may be a filter behind each one or behind one large central return grill.

    CAUTION: Be sure to turn off your HVAC equipment before removing panels or filters.

  • Once you've found the filter, look at the surface of it. Clean filters will be white and pristine. If it's grey, shows signs of wear and tear, or is covered in hair, it's time to change it. Hold the filter up to a light source. If you can't see light through the filter, it must be replaced.

    CAUTION: Turn the power off to the indoor HVAC unit while replacing the air filter to avoid injury from contact with rotating parts.

Was a dirty furnace filter the issue? If not, consider other problems pointing to why your furnace is on the fritz.

What To Do If You Have A Dirty Furnace Filter?

If you notice enough dirt and debris on your filters to strain your system, it’s time to change the filter. Changing the filter every month can help prolong the efficiency and lifespan of your furnace so you can keep your home warm and cozy all winter long.

Think you’ll need a helping hand? Reach out to one of our Remote Assist technicians to guide you through the filter cleaning process and get your heat back on track.

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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