Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Fast, Reliable HVAC Cleaning Across Boulder
HVAC cleaning in Boulder, CO typically runs $425 – $775 for a full system clean on a standard single-family home, and the work usually takes half a day. We serve every neighborhood from Mapleton Hill to South Boulder with background-checked technicians who carry Rotobrush agitation tools, Nikro HEPA vacuums, and Abatement Technologies containment units. Call (737) 727-2314 and you’ll get a live person, a written price before any work starts, and a trackable arrival window. If you live in Boulder, you already know the dust story: dry winters, summer wildfire haze, and older homes that haven’t had their ducts opened in decades. We know it too.
Why Cardinal Air Duct Cleaning Is Boulder’s Preferred HVAC Cleaning Company
Boulder homeowners call us because we treat old houses like they’re old. A 1910 Whittier bungalow with original plaster-encased ducts and a 2005 tract home in North Boulder need different pressure, different agitation, and different patience. Our techs know both. We’re part of the Relay Home Co. family, founded 2005, and every single job is backed by the 365-Day Done Right Promise: if the work isn’t right within a year, we come back and correct it at no charge. No fine print on which jobs qualify.
We also handle the logistics the way Boulder expects: a live trackable arrival window on your phone, before-and-after photos of your own ducts, and a digital invoice you can pay from a link. You never guess when we’ll show up or whether the work actually happened.
Furnace Duct Cleaning in Boulder
Furnace Duct Cleaning in Boulder means reaching the supply and return runs that have been collecting whatever your home breathes: fine clay dust off the Front Range, pet dander, construction debris, and the occasional surprise nobody wants to discuss. In a Boulder house with forced air, the furnace pushes air through these ducts every cold morning from October through April, and what’s stuck to the duct walls keeps circulating. A typical furnace duct cleaning here runs $275 – $475 for the ductwork on a standard home, and we photograph everything before and after so you see exactly what came out.
Older Boulder Homes, Gentler Tools
When ducts are buried in lathe-and-plaster walls, as they are throughout Mapleton Hill and much of Whittier, we swap stiff nylon agitation brushes for softer contact tools. The goal is the same: break the debris loose without cracking brittle plaster or dislodging original duct liner. Camera inspection tells us which approach is safe before we start.
One Flat Price Per System
We quote the whole duct system as one job. Not per vent. Not per register. Older Boulder homes often have many small registers, and per-vent pricing punishes them unfairly. Our written price covers the full furnace duct system, the air handler, and the blower motor compartment before we touch anything.
AC Coil Cleaning in Boulder
AC Coil Cleaning in Boulder is the difference between an air conditioner that struggles through July and one that actually cools. The evaporator coil sits above your furnace or inside the air handler, and when it’s coated in a mat of dust and lint, two things happen: the system works harder, and the air coming out of your vents isn’t as cold or as clean. Most Boulder homes run AC from June through September, often through wildfire smoke season, and a dirty coil makes that worse. A standalone AC coil cleaning typically runs $180 – $320, and it’s included in our full-system price when you book the whole HVAC clean.
Why Skipping the Coil Makes Duct Cleaning Pointless
You can clean every duct in the house and still have dusty air if the evaporator coil is caked. Air passes over that coil before it reaches your registers. That’s why our HVAC cleaning always includes the coil, the blower motor, and the air handler compartment as one job. We use Nikro HEPA extraction to capture what we loosen, so debris goes into the vacuum, not back into your living room.
Coil Treatment for Boulder’s Dry Air
Boulder’s low humidity and big seasonal swings dry out old coil sealant and leave aluminum fins dusted with a fine, almost abrasive grit. We apply a coil-safe treatment after cleaning that helps the fin surface shed future dust. It’s a small step that keeps the coil breathing longer, and it’s part of the standard clean, not an add-on you’ll discover on the invoice.
Trusted Brands We Service in Boulder
We work on every major system in Boulder homes, including Honeywell, Aprilaire, and Abatement Technologies filtration units, plus Bryant, Carrier, Lennox, Trane, and Goodman furnaces and ACs. Our trucks carry common filters, coil treatments, and replacement parts sized for Boulder’s most common installs, so we rarely need to order and return. If you have an Aprilaire media cabinet or a Honeywell whole-home filter that hasn’t been opened in a while, we’ll inspect it and tell you honestly whether it’s doing its job. That’s part of the HVAC Cleaning service.
Common HVAC Cleaning Problems We See in Boulder Homes
- Dried-out duct sealant cracking from seasonal swings. Boulder’s weather flips from dry, windy spring days to hard winter freezes, and old sealant around duct joints shrinks and splits. That pulls dust in from attic and crawlspace spaces, which then showers down through the registers.
- Plaster-encased ducts in pre-1940 homes. Mapleton Hill and Whittier houses were built before modern flex duct. Their supply and return runs are often tin or even wood-lined channels inside plaster walls. The wrong tool or too much air pressure can crack the wall. We camera-inspect first, agitate gently, and pull negative pressure with HEPA filtration instead of blasting.
- Blower motor compartments full of lint. When a filter sags or gets installed wrong, unfiltered air bypasses it and dumps directly into the blower. We find this constantly in Boulder homes with original 1920s-era filter slots and modern high-MERV filters crammed in.
- Wildfire smoke residue on coils and ducts. Summer smoke leaves a fine, oily film on evaporator coils and the inside of return ducts. It’s why a house can smell faintly of smoke when the AC first kicks on in late summer. Coil cleaning and duct agitation both address it, but the coil is usually the bigger culprit.
Pricing for HVAC Cleaning in Boulder, CO
Here’s what we actually charge in Boulder. A full HVAC clean, meaning furnace ducts, supply and return runs, the air handler, blower motor, and evaporator coil, runs $425 – $775 for a typical single-family home up to about 3,000 square feet. Furnace duct cleaning alone runs $275 – $475. AC coil cleaning alone runs $180 – $320. Larger homes, multiple systems, or heavily soiled ducts from renovation dust can push the top end higher, but you’ll know the exact price before we start. You get one flat price per system in writing, no per-vent math, and no surprise line items at the door. Call (737) 727-2314 for a free phone estimate.
We Also Serve Cities Near Boulder
Cardinal Air Duct Cleaning handles HVAC cleaning across the Front Range. We serve Boulder and the surrounding metro, with crews also covering Denver, Greeley, Fort Collins, and Colorado Springs. If you’re in a nearby town and need the same flat-price, photo-documented service, call us at (737) 727-2314.
Serving Boulder, CO - Our Local Coverage Area
We’re based in the Boulder area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About HVAC Cleaning in Boulder
Every 3 to 5 years for most Boulder homes, and closer to every 2 to 3 if you have pets, live near open space with blowing dust, or run your system through wildfire smoke season. If you’ve renovated recently or bought an older Boulder home with no service history, do it once now, then reassess after two years. A quick look with a camera will tell you more than a calendar. Call (737) 727-2314 and we’ll give you an honest read.
Per system. Always. Per-vent pricing is a red flag, especially in older Boulder homes with many small registers. We quote one flat price for the entire HVAC system, written down before any work starts, and it does not change at the door.
In a pre-1940 home with plaster-encased ducts, we start with camera inspection to see what we’re dealing with. Then we set up negative pressure with a Nikro HEPA vacuum so the house stays clean while we work. We use soft agitation tools through the supply and return runs, clean the air handler, blower motor, and evaporator coil, and show you before-and-after photos of your own ducts. One flat price per system, agreed before we begin.
Yes, in almost every case. We pull up to homes near Pine Street and 15th in Whittier and Mapleton Hill regularly, and the approach is just different: gentler tools, lower pressure, and more camera guidance. What we won’t do is run stiff agitation through your walls and risk cracking the plaster or the old liner. If a section of duct is collapsed or beyond cleaning, we’ll show you the camera footage and tell you exactly what we found.
Yes, when you book a full HVAC clean, the evaporator coil, blower motor, air handler, and furnace duct system are all included. That’s the whole point: cleaning just the ducts while leaving the coil dirty means dust returns to your registers within weeks. Call (737) 727-2314 for an exact quote, and we’ll walk you through what’s included.
Call (737) 727-2314 today for a free estimate on HVAC cleaning in Boulder. A live person answers, you get a written price before any work begins, and every job is backed by the 365-Day Done Right Promise.
Written by Omar Haddad, Owner at Cardinal Air Duct Cleaning, serving Boulder with straightforward pricing and photo-documented work.




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