How we clean air ducts.
Air duct cleaning removes the dust, debris and allergens that build up inside a home’s heating and cooling system. Done properly it covers the whole system — not just the vents you can see — and everything that comes out leaves the house. Six steps, every job:
Seal every register
Every supply and return opening is covered before anything is disturbed, so nothing knocked loose inside the ducts can blow out into the room.
Connect the truck-mounted HEPA system
A HEPA-rated vacuum on the truck is connected straight to the ductwork and runs the system under negative pressure. What comes out leaves the house — it isn't filtered and blown back in.
Main return and supply trunks
Brushed, air-washed with compressed-air tools and HEPA-vacuumed — the main lines every room's air passes through.
Blower, housing and coil
The blower and its housing are air-washed and vacuumed. The coil is vacuumed, washed and sanitized — buildup there restricts airflow before the air even reaches the ducts.
Every supply line, every cover
Each branch to each room is brushed, vacuumed and washed where it needs it. Every vent cover comes off and is hand-cleaned before it goes back.
Sanitize and close up
The system is sanitized with a non-toxic, biodegradable solution. If a unit needs an access panel to be cleaned properly, we install one — one per unit, at no charge.
What it looks like.
The same register opening in an East Patchogue home, before and after — and the job in between.
Registers sealed before anything is disturbed 
Truck-mounted HEPA hose on the trunk line 
Compressed-air tool working each supply line 
Every cover hand-cleaned before it goes back
Signs it’s time.
The National Air Duct Cleaners Association puts the interval at every 3 to 5 years for most homes. Some houses need it sooner — and the ducts rarely show it until you look inside.
A musty smell when the system kicks on is the one sign that isn’t about dust. That’s a mold question first.
Book a cleaning if
- You can see dust at the registersOr it comes back on surfaces days after you clean.
- You've renovatedDrywall and sawdust settle in the ducts and circulate with every cycle.
- There are pets in the houseHair and dander clog ducts faster than in homes without them.
- Allergies are worse indoorsDust, pollen and dander in the system go wherever the air goes.
- It's been more than 3–5 yearsOr nobody knows when it was last done.
- After water or mold damageSpores and debris sit in the system and recirculate.
What it costs.
There’s no flat price, because a one-unit ranch and a three-zone house on the East End aren’t the same job.
Included every time: register sealing, the full system from trunks to covers, coil cleaning and sanitizing — and an access panel, one per unit, at no charge if one is needed.
Free estimate. The price you’re quoted is the price you pay.
Size of the system
More rooms mean more supply lines and registers to brush, vacuum and wash — the biggest driver of time on the job.
Number of units
Each air handler has its own blower, coil and trunk lines, so a two-zone house is closer to two systems than one.
How much buildup
A system cleaned a few years ago goes faster than one carrying construction dust, pet hair or decades of accumulation.
When it's more than dust
Mold in the ducts is a remediation job.
Recent air duct jobs.
Written up start to finish, with the photos from the job.
Before you book.
Longer answers to the questions people ask before they call.
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Frequently asked questions
Straight answers on cost, timing and what the job involves.
How much does air duct cleaning cost?
It depends on the size of the system, how many units the house has, and how much buildup is inside — which is why the estimate is free and done first. The price you're quoted is the price: no hidden fees, sanitizing included, and an access panel installed at no charge if a unit needs one.
How often should air ducts be cleaned?
Every 3 to 5 years for most homes — the National Air Duct Cleaners Association guideline. Sooner with pets or allergies in the house, after renovation work, or after water or mold damage.
How long does it take?
Most homes take 1.5 to 3 hours, depending on the size of the system and how much buildup there is.
Is air duct cleaning worth it?
When there's something to remove, yes: visible dust at the registers, a recent renovation, pets, allergies that are worse indoors, or a system that hasn't been cleaned in years. After water or mold damage it's part of the job, not an extra. If the ducts were cleaned recently and nothing has changed, it can wait.
Is it messy? Does the dust end up in the house?
No. Every register is sealed before we start, and the truck-mounted HEPA system runs the ducts under negative pressure, so what comes loose is pulled out of the house rather than blown into it.
Do you clean the vents in every room?
Yes. Every supply line is cleaned, and every vent cover is removed, hand-cleaned and sanitized before it goes back on.
When is the best time of year to clean air ducts?
Early fall, before the heat comes on and the system runs all winter — or spring, before the air conditioning does the same all summer.
What if there's mold in the ducts?
Then it's a remediation job, not a cleaning job — the moisture feeding it has to be found and the growth removed properly. K.O.S. is an IICRC-certified mold remediation company, so the same company handles it.
Get a free air duct quote.
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Call for a quote(631) 560-8999