Signs Your Air Ducts Need Cleaning

Short answer: The clearest signs are dust or debris blowing out of the vents, visible mold in the ducts or on the registers, signs of mice or insects, and heavy dust you can see when you pull off a register. Recent renovation dust and moving into a home with an unknown history are good reasons to have them checked.

Dust and debris cleared from an air duct by Mansfield Services

Signs your ducts need cleaning

Dust or debris puffs out of the registers when the system turns on.
Heavy buildup inside the duct when you take off a register cover and look in with a flashlight.
Visible mold inside the ducts or on the registers.
Droppings, nesting material or a dead-animal smell from the vents.
You renovated and drywall dust or sawdust got into the system.
You moved in and don’t know if the ducts were ever cleaned, especially if past owners had pets or smoked.

Signs that don’t mean much on their own

A light layer of dust on the register covers. That’s normal in any home.
Dusty furniture. Household dust comes from many places, not just the ducts.
A company calling to say it’s been a while. The EPA says ducts don’t need cleaning on a routine schedule.

How to check your ducts yourself

Unscrew a supply register and a return grille and shine a flashlight inside. A thin, even film of dust is normal. Thick, matted dust, debris, droppings or growth means it’s worth having the system cleaned. Check the return side too; it often collects the most.

Fix the cause first

If there’s mold or pests, the EPA says to fix the source, like a moisture problem or a gap where mice get in, or the problem will come back after cleaning. In Vermont, damp basements are a common source of mold near the ductwork.

What our cleaning covers

We use a powerful HEPA-filtered vacuum and air-powered agitation tools to pull dust and debris out of your supply lines, return lines and main trunk lines, and we clean the registers and grille covers. The dust ends up in our equipment, not your home, and our crew wears boot covers inside. Most air duct cleaning jobs we do run about $1,500 to $2,500, priced from your home’s size, how many furnaces or systems you have, and how many supply and return vents there are.

Frequently asked questions

How do I know if my air ducts need cleaning?

Pull a register and look inside. Thick dust, debris, mold or signs of mice mean it’s time. So does dust blowing out of the vents.

Is dust on my vents a sign the ducts are dirty?

A little dust on the covers is normal. Dust blowing out when the system starts, or thick buildup inside the duct, is the real sign.

Should I clean the ducts after a renovation?

Yes, if construction dust got into the system. Drywall dust and sawdust can collect in the ducts and blow back out.

Can mold grow in air ducts?

Yes, where there’s moisture. If you see mold, fix the moisture source and have the system cleaned.

Sources

Have your ducts checked and cleaned

Mansfield Services cleans air ducts across Chittenden, Lamoille and Franklin counties. Book online in a couple of minutes, or call or text (802) 777-3210.

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Signs Your Air Ducts Actually Need Cleaning