How Often Do I Need to Clean Air Ducts in My HVAC System?

Appliance professionals suggest that you get your HVAC system serviced at least once a year to keep everything running smoothly. But did you know that you’re on a much longer time frame for cleaning your air ducts? The exact guidance for how often to clean air ducts can vary depending on who you listen to, but we’ll cover official guidelines from two different reputable sources and some obvious signs it’s time for a cleaning below. 

How Often to Clean Air Ducts

The National Air Duct Cleaning Association (NADCA) suggests a cleaning schedule of every three to five years. However, the Environmental Protection Agency (EPA) suggests doing so only on an as-needed basis. The EPA states that air duct cleaning has not been proven to prevent allergies or other health problems. Even if your air ducts are indeed dusty, the particles will likely stick to the interior of the ducts and not come through the air into your home’s interior. 

So, if you go by the NADCA’s recommendation, which side of the three-to-five-year spectrum do you choose? And if you choose the EPA’s recommendation of cleaning only as needed, how do you know when your air ducts need cleaning? Let’s explore some clear-cut signs that it’s time for a cleaning.

5 Signs That It’s Time to Clean Your Air Ducts

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Knowing how often to clean air ducts on average is great, but it can also help to keep an eye out for some of the telltale signs that your system needs cleaning earlier than usual. 

There’s Mold in the HVAC System

Condensation forms when either your AC or furnace is hard at work. While that moisture is supposed to drain out of your house, there is a chance for it to stimulate the growth of mold, particularly if you live in a region with a humid climate.

It’s important to note that not all mold is toxic, nor is your HVAC technician necessarily trained to recognize mold. However, the threat of mold is enough for you to inquire with an air quality expert who can examine and test air samples to see if your home’s interior is at risk of mold. 

If mold is found to be growing in your HVAC system, it might not have affected the air ducts just yet. However, it’s better to be safe than sorry. This would be a good time to call your local air duct cleaning company and schedule a service visit. This is especially important to do if you or someone in your household is experiencing unexplained allergies or other adverse symptoms. Again, the EPA says dust-free vents won’t prevent allergies, but mold- and microbe-free ones certainly will.

You’ve Bought a Brand-New Home or Completed a Major Renovation

You might think, “Brand-new build, brand-new ducts—why bother cleaning?” Well, considering the amount of sawdust that spreads across the floor (and everywhere else) during construction, it’s likely that some of it—along with the dust of other building materials—got into your air ducts. It’s a good idea to have them cleaned out before you fire up the furnace or turn on the AC for the season.

Your Home Is Dusty Despite Frequent Cleaning

Everyone gets a little behind on dusting every now and again. But if you’ve been diligent in your housekeeping duties and other simple HVAC maintenance tasks and still have a layer of dust on everything, your air ducts could be to blame.

Again, the EPA says that some dust particles will become stuck to the interior walls of the air duct and won’t come through the vents. But if there is an overabundance of dust in the ducts, it will filter out through the vents onto floors, walls, furniture, and other surfaces in your home. Inspect the supply registers. If they’re dusty, a good vacuuming with a brush attachment could do the trick.

Your Home Doesn’t Warm Up/Cool Down Efficiently

Clean appliances will work more efficiently than dirty ones. In addition to cleaning or replacing the HVAC filter at least once each season—more often if there are pets or smokers in the home—you should have the ducts inspected and cleaned, if necessary.

Pests Have Gotten Into the Ducts

The droppings of rodents and vermin are known to trigger allergic reactions or worse in humans. If you suspect that you’ve got a pest infestation in your home, don’t forget to have your air ducts checked and cleaned, if necessary.

How Much Does It Cost to Have Your Air Ducts Cleaned?

The average cost to clean your home’s air ducts is $380, though it could range between $150 and $780. The actual cost to have your air ducts cleaned will depend on the size of your home—larger homes simply have more ductwork—as well as the type and condition of your air ducts. Ducts with a significant mold or pest problem will cost more to clean due to the safety protocols and specialized equipment involved.