Why Are My Air Ducts Dirty? | How to Prevent Dirty Ductwork - Service ChampionsService Champions
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Why Are My Air Ducts Dirty? | How to Prevent Dirty Ductwork

April 23rd, 2019

One of our customers recently found out that he has some pretty dirty air ducts, and now he wants to know why. Bill writes:

“Hey there, Service Champions. It’s your old friend Bill here, and I’m sorry to say, I think that I have a bit of a dirty question for you all to answer. See, I’ve gone and neglected getting the air ducts in my house cleaned. The last time I had anything tidied up in that area was… well… now that I try to recollect, I don’t think I’ve ever had them cleaned, and I’ve lived in my house more than 12 years! So, let me start by apologizing for my mess.

That said, I’ve been noticing that there seems to be a good deal of dirt and dust coming out of my ducts. So, putting my obvious negligence aside, is there any other reason for this? What I want to know is, why are my air ducts so dirty? And, while I’ve got your attention, could I also trouble you and ask what — if anything — I can do about my dirty air ducts? I always like reading your answers to other folks’ questions, and I thank you kindly in advance for also taking some time out to answer mine.”

Bill, it seems like you know what you’ve done wrong, so I won’t wag a finger at you. Second of all, gross (and I do mean gross) negligence aside, your question is a good one because there could be other reasons for dirty ducts that go beyond simple neglect. And trust me, you’re not alone. As professional HVAC technicians who encourage questions, this is a fairly common one, which is why it’s our pleasure to answer your question.

Common Causes Why Your Air Ducts May Be So Dirty

The answer to why your air ducts may be so dirty is because they pull in air from both inside and outside of your home (in some systems), air that may carry with it dust and debris. If you’re not having your ducts regularly cleaned, that dirt and debris tends to pile up. While this isn’t the only answer for why your air ducts are so dirty, it is the most common one.

Other causes include not having your filters changed properly and regularly, leaky ductwork, poorly sealed ducts, and having HVAC ducts that should be modified or replaced.

Since the air filter is designed to keep airborne particulates from getting into your home’s duct system, that cause is easy enough to understand. If it’s clogged or dirty, it just can’t do its job well. If it’s a leak, or your ducts need to be replaced, that’s a little more complex. Finally, part of the answer to why your air ducts are so dirty is that our Northern California region is a dusty one, heavy with allergens, so there’s simply more gunk to filter out than might be the case in other areas.

How to Prevent Dirty Ducts and Keep Your HVAC System Clean

So, yes, dirty ducts do happen. That’s a fact. With that in mind, though, the question turns from, “Why are my air ducts so dirty?” to “What can I do to keep my air ducts clean?”

  1. Use a high-quality air filter and replace it often

Ensure that you have a high-quality filter (MERV 10-14) that fits your HVAC system. That’s step one.

Step two is making sure you change it regularly. I know life can get busy, but by setting monthly calendar reminders to inspect the cleanliness of your filter, you can help ensure a clean HVAC system and better indoor air quality all year round.

  1. Always schedule HVAC maintenance, repair, and replacement from a reputable, certified professional

If you’re spending the money on HVAC maintenance, repair, or replacement, ensure it’s done right the first time by learning how to choose the HVAC contractor for the job. When ducts are properly installed and sealed in the beginning, you may never have to worry about dirty ducts or professional duct cleaning.

When replacing your HVAC system, consider replacing your ducts as well. A reputable contractor will be able to tell you whether you could benefit from a duct system replacement or not.

  1. Consider professional duct cleaning and sealing

Having your ductwork regularly cleaned is also important, but in light of the causes above, some ducts get dirtier a lot faster than others. In general, your home and HVAC system may benefit from professional duct cleaning every 5 years or so.

An experienced HVAC company can help you inspect your ductwork and recommend solutions. For instance, our PureFlow™ Duct System will completely seal and insulate your ducts for increased energy efficiency and a cleaner HVAC system.

During your duct cleaning, our trained technicians will check for leaks in your ducts, or let you know whether they should be replaced soon.

  1. Keep your home clean

The more you dust and vacuum the inside of your home, the less dirt and dust will enter your HVAC system. Learn spring cleaning tips for improving indoor air quality and reducing the amount of airborne contaminants that enter your duct system. You may also want to seal up air leaks around your home to prevent dirty outdoor air from entering.

The best option is to call an experienced HVAC maintenance and repair company. Experts will not only be able to change your filter and clean your ducts, but they’ll also be able to let you know if you have any leaks or if your ducts need to be replaced. Basically, they can give you invaluable pieces of information and recommendations for improvement.

Bill should, obviously, do a better job of getting his ducts cleaned, but he’s far from the only one in Northern California who struggles with dirty ducts. Having a trained HVAC company perform regular maintenance twice a year is the best way to ensure a clean, healthy, and efficient HVAC system.

Sign up for our Maintenance Value Plan (MVP) and receive two precision HVAC tune-ups a year, discounts on repairs and replacements, plus much more. Learn more about our duct cleaning and sealing services.

If you have any questions about your heating and cooling system, don’t hesitate to Ask a Champion!

Service Champions is known for trustworthy, on-time heating and air conditioning service throughout the East Bay, South Bay, and Sacramento areas.

For help getting your air conditioning system ready for summer, schedule your $78 AC Tune-Up today!

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