Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-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.
Air Duct Cleaning Company in Walnut, CA
Air duct repair in Walnut usually means one of two things: a disconnected or crushed flex duct, or a leaking sheet-metal joint that has been pulling attic dust and heat into the system for years. Most Walnut homes were built between 1980 and the early 2000s, which puts a lot of that ductwork at the 20-to-40-year mark, right when seams fail, insulation breaks down, and rodents start finding their way in. Combined with heavy AC use through the long San Gabriel Valley cooling season and Santa Ana wind grit in the intakes, Walnut systems get worked hard. Call Cobalt Air Duct Cleaning at (866) 596-7835 when you want a ducts-first diagnosis instead of a filter-first guess.
Why Walnut Homes Are Different
Walnut splits naturally into two working conditions. The flatland tracts along the 60 freeway corridor, especially the 91789 and 91795 ZIPs, run predictable single-story and two-story layouts with standard attic runs. But the homes climbing toward the San Jose Hills in 91788 are different jobs entirely. Those slopes produce longer, more convoluted duct runs, tighter mechanical closets, and attic spaces where equipment placement was adapted to the terrain, not the builder’s original floor plan. That means a repair on a hillside home often takes longer to trace, and a leak there pulls in more of the fine grit the Santa Ana winds push up against the foothills every fall.
Most of this housing stock is from the 1980s through 2000s, heavily planned subdivisions with HOAs that take code enforcement seriously. Walnut homeowners tend to want documentation before work begins: what will be opened, what will be replaced, and whether anything touches the exterior. Cobalt works that way by default. We explain the scope before the van unrolls a hose, and we respect the neighborhood rules about access, noise, and exterior equipment.
Styles & brands we work with
- Whole-home duct cleaning
- Dryer vent cleaning
- Camera inspection
- Sanitizing & deodorizing
Our Main Walnut Services
Walnut homeowners call Cobalt for two jobs more than any others, and they are related. The first is a full indoor air quality cleanup of the ducts themselves. The second is the dryer vent, which in Walnut’s dry, hot summers can become a combustion hazard faster than people expect.
Air Duct Cleaning in Walnut
Walnut’s HVAC systems run long seasons. April through October means constant air movement, and every Santa Ana event pushes fine dust, pollen, and sometimes wildfire ash toward the intake grilles. Over time that accumulates in the return and supply runs, and in 1980s-era flex duct it collects on the inner liner where you cannot see it. A full Air Duct Cleaning in Walnut job starts with a camera inspection inside the plenum and representative supply runs, so you see the contamination levels before any cleaning begins. We then run our Rotobrush or Nikro mechanical agitation systems through every accessible run, with negative air held at the trunk. No per-vent pricing. One flat quote per system, agreed before the work starts.
Dryer Vent Cleaning in Walnut
In Walnut’s dry inland heat, lint inside a dryer vent loses moisture fast. That makes it more combustible, and in a two-story home where the vent rises through a wall and exits at the roofline, the lint packs in the vertical rise. Dryer Vent Cleaning in Walnut is a separate, dedicated service with Cobalt: a full-lumen inspection, mechanical brushing of the full run wall to termination, and a measured airflow test before and after. If the vent route is the common Walnut configuration of a second-story laundry with a roof termination, expect the first cleaning to take longer. We treat it as a fire-safety job, not an add-on.
Air Duct Repair in Walnut
Air duct repair in Walnut is not the same as duct cleaning, and it is the step that gets skipped far too often. A duct system that was sealed with contractor-grade foil tape in 1992 has been leaking for decades. That leak pulls in attic heat around the plenum, pulls in insulation fibers at the joints, and sends conditioned air into spaces nobody cools. Cobalt performs standalone Air Duct Repair, which means we find the failed joint, the collapsed flex run, or the separated takeoff and fix it, rather than cleaning around it. In Walnut’s hillside homes especially, a crushed or kinked flex run behind a chase wall can quietly cut airflow to a whole upstairs bedroom for years before anyone notices.
Ductwork Repair
Signs you need it
Rooms that never hold temperature, visible dust streaks at supply grilles, or a sudden jump in cooling cost are the three tells Cobalt sees most often in Walnut homes.
What it costs in Walnut
Ductwork repair typically runs $300 to $700 in Walnut, depending on how many access points and runs are involved.
How we do it
We locate the failure with a camera drawn through the duct body, open only the access needed, reseal with fiber-reinforced mastic and appropriate UL-rated tape, and verify the repair with a static-pressure and airflow check.
Air Duct Replacement
Signs you need it
Mold on the inner duct liner, collapsed flex sections, or material that has been compromised by rodents requires replacement, not patching.
What it costs in Walnut
Air duct replacement on a standard Walnut two-story system typically falls in the $1,200 to $2,800 range, sized by the number of runs and the attic access difficulty.
How we do it
We map every run from plenum to register, pull the failed sections, install new flex or sheet-metal duct sized to the original Manual D calculation, seal all connections with mastic, and rebalance airflow at the grilles.
What Air Duct Repair Costs in Walnut
| Item | Typical range in Walnut |
|---|---|
| Ductwork repair (single joint, access point, and reseal) | $300 – $700 |
| Air duct replacement (multiple runs) | $1,200 – $2,800 |
| Full HVAC duct installation (new build or major renovation) | $3,000 – $6,000+ |
Hillside access, longer runs, and the need for code-compliant HOA approvals push Walnut quotes toward the higher end of each range. We agree on one flat price before the first cut is made, so the number you approve is the number on the invoice.
Can you repair just one duct run, or do I need the whole system done?
Yes, Cobalt repairs single failed runs in Walnut. We isolate the failed section, camera the adjoining lengths to confirm they are sound, and seal only what failed. A full replacement is recommended only when the material itself has failed or is contaminated.
Do Walnut hillside homes cost more to repair?
Sometimes, yes. Walnut homes on the San Jose Hills slopes often have longer, angled runs and tighter attic access, which means more labor to reach and reseal the failed section. The repair itself is priced by the run and the access points, not by the square footage of the house. Call (866) 596-7835 for a flat quote based on your specific layout.
Brands We Service in Walnut
We work on systems tied to Honeywell and Aprilaire filtration and air quality components, and we stock Rotobrush and Nikro cleaning heads and Guardsman-grade protective materials locally. Walnut jobs generally take one visit for a diagnostic and one scheduled visit for the repair or cleaning itself, with everything needed brought on the first truck roll. See our brands for the full list of what we service.
See the difference
Before
After
Before
After
Before
AfterPricing for Air Duct Cleaning Company in Walnut, CA
| Service | Typical range in Walnut |
|---|---|
| Air duct cleaning (whole system) | $350 – $700 |
| Air duct cleaning (partial or single-zone) | $175 – $350 |
| Ductwork repair (single joint, access point, and reseal) | $300 – $700 |
| Air duct replacement (multiple runs) | $1,200 – $2,800 |
| Dryer vent cleaning | $90 – $165 |
| Duct sanitizing (add-on with cleaning) | $100 – $250 |
| Air filter replacement (Honeywell/Aprilaire media) | $25 – $65 |
| HVAC duct installation (new build or major renovation) | $3,000 – $6,000+ |
Three things push a Walnut quote higher: attic access difficulty on hillside lots, the number of supply runs in a larger two-story floor plan, and HOA noise or hours restrictions that mean we phase the job across shorter work windows. Every Cobalt job is priced as one flat number per system, so there’s no per-vent math and no surprise line item once the work begins.
Neighborhoods We Serve in Walnut
Cobalt runs jobs across every Walnut ZIP: 91788, 91789, and 91795. We service the hillside subdivisions climbing toward the San Jose Hills, the flatland tracts along the 60 corridor, and the older ranch-home pockets near the city’s commercial spine.
- Snow Creek (foothills, 91788)
- Brea Canyon area (north Walnut, 91789)
- South Walnut flatlands along La Puente Road corridor (91789/91795)
- Timberline and adjacent hillside tracts (91788)
- Walnut City limits near Mt. San Antonio College (91789)
We schedule Walnut jobs around the morning and early afternoon when attic temps are manageable, and we batch same-day bookings by ZIP to keep response time within a day or two of first contact depending on your service.
Service Area – Cities Near Walnut
Cobalt Air Duct Cleaning covers Walnut and the surrounding foothill and valley communities. We run jobs in South San Jose Hills, CA, where the terrain and older duct systems mirror Walnut’s hillside conditions, and in Valinda, CA, where the 1980s tract homes have similar flex-duct aging patterns. We also service Irwindale, CA and West Puente Valley, CA for flatland single-story systems with their own access and replacement considerations.
Serving Walnut, CA – Our Local Coverage Area
We’re based in the Walnut 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 Air Duct Cleaning Company in Walnut
Most Walnut appointments are scheduled within one to two days, and we batch calls by ZIP code so hillside jobs in 91788, flatland jobs in 91789, and south Walnut jobs in 91795 get routed efficiently. A system that has been leaking for years will not get worse by waiting 48 hours. We will give you a firm window when you call.
That depends on your subdivision’s CC&Rs. Interior duct repairs and cleanings with no exterior equipment changes rarely require Walnut HOA review. But if we need to cut a new attic access or replace a roof vent cap, most Walnut HOAs want advance notice. We will flag that during the diagnostic and give you a straightforward scope description to pass along.
Yes, the price ranges are consistent across 91788, 91789, and 91795. What varies is the quote itself, because a hillside home with 14 supply runs and difficult attic access will cost more than a flatland home with 8. The range is fixed; the actual number reflects the system you actually have. Call (866) 596-7835 for a flat-quote estimate built from your home’s specifics.
What happens when you call
- 1A real person answersNo phone trees. Talk to a local air duct cleaning pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you. The visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Walnut Customers Say
"Found a disconnected run in the crawlspace while they were in there and told me about it rather than cleaning around it."
- Alejandro Ramirez"Quoted per system rather than the bait and switch per vent pricing everybody else in town uses. The number I was told on the phone was the number on the invoice."
- Kevin Wong"Fair price, competent work. The guy wasn't especially chatty and I had to ask twice to get a real explanation of what he'd done. Not a dealbreaker, just noting it."
- Veronica Rodriguez