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 San Francisco
HVAC cleaning in San Francisco usually costs between $450 and $900 for a complete furnace and AC vent cleaning on a typical home, and the work takes about 3 to 5 hours. That’s the honest range you should expect, not a teaser number that triples once a technician walks through the door. We serve every corner of San Francisco, from the Outer Richmond to Bayview, with written pricing before any work starts and before-and-after photos of your own ducts. Call (737) 727-2314 for a free estimate.
San Francisco’s housing stock is unlike almost anywhere else in the country. Most homes predate 1940, which means galvanized ductwork, converted wall cavities, and returns that run through crawlspaces and garages. That changes what honest duct cleaning actually involves here. Our crews know the difference between a duct that’s full of dust and a duct that’s pulling damp fog-air through a failed seam in the Inner Sunset.
Why Cardinal Air Duct Cleaning Is San Francisco’s Preferred HVAC Cleaning Company
We’re part of the Relay Home Co. family, founded in 2005, and our San Francisco Bay Area office dispatches background-checked, uniformed technicians to neighborhoods throughout the city. Our local reputation rests on one thing: we show you the work. Every booking includes The Relay Standard, which means a live trackable arrival window, before-and-after photo documentation, and a digital invoice you can pay from your phone. No vague four-hour windows. No price that shifts at the door.
Homeowners in neighborhoods like Noe Valley, the Mission, and the Richmond District tell us the same thing: they called another company, got quoted a low per-vent price, and then watched the invoice balloon once the tech counted registers in a three-story Victorian. We don’t do per-vent pricing. We quote one flat price per system before any work begins, and that number doesn’t change.
Our technicians run professional-grade equipment: Rotobrush rotary brush systems for agitation, Nikro HEPA-rated vacuums for negative-pressure extraction, and Abatement Technologies containment units when the job calls for it. That means loosened debris goes straight into the vacuum, not back into your living room. Omar Haddad, who leads our team, holds every job to a simple standard: total visibility from booking to invoice.
Furnace Cleaning in San Francisco
Furnace cleaning in San Francisco typically runs $300 to $550 as part of a full-system cleaning, and it’s the most important sub-service for this city’s housing stock. Because San Francisco sits in a fog belt, most furnaces run lightly compared to inland cities, but the ductwork around them sits in damp crawlspaces and garages where condensation, rust, and sometimes rodent activity create contamination that a simple filter change won’t touch. A furnace cleaning here means cleaning the blower assembly, the heat exchanger, the evaporator coil if you have AC, and the immediate supply and return plenums.
If your furnace kicks on and you smell something musty or stale in a pre-1940 building, the problem is often a separated return seam pulling damp outside air into the system, not just dirty registers. We inspect with a camera first, then clean with source removal and negative pressure so the debris goes into our HEPA vacuum, not your air.
Blower and Heat Exchanger Cleaning
The blower wheel in a San Francisco home often collects a fine film of rust and dust from the marine layer. We remove the blower, clean each fan blade, and check for imbalance or bearing wear. A dirty blower runs hotter and pushes less air, which means your furnace works harder for the same heat. The heat exchanger gets inspected and cleaned at the same time, since a fouled exchanger reduces efficiency and can be a safety concern in older units.
Evaporator Coil Treatment
If your San Francisco home has central AC, the evaporator coil sits right in the airflow path and collects a damp, sticky layer of dust that reduces cooling performance. We apply a professional coil treatment after cleaning to restore heat transfer and reduce odors. This matters most in homes that run AC only a few months a year, because the coil stays damp longer between cycles and grows more biological material than in year-round cooling climates.
AC Vent Cleaning in San Francisco
AC vent cleaning in San Francisco runs $150 to $350 on its own, and it covers the supply registers, return grilles, and accessible duct branches. In an Edwardian or Victorian flat, a surprising amount of the airflow path runs through old wall cavities that were converted to returns decades ago. Those cavities collect plaster dust, paint chips, and debris from every renovation since the 1920s. We clean the register faces, vacuum the accessible branches, and photograph what we remove.
Vent cleaning matters differently here than in air-conditioning-heavy cities. San Francisco’s marine layer keeps humidity in the 70 to 80 percent range most of the year, which means dust in the vents stays damp and sticky instead of dry and loose. That damp dust is what causes the musty smell when the blower kicks on, and it clings to the vent walls. Dry-brush-only cleaning from a truck-mounted shop vac often doesn’t remove it.
Return Duct Inspection and Sealing
The return side of the system is where San Francisco homes fail most often. Returns run through crawlspaces, garages, and wall cavities, and when a seam separates, the system pulls in unfiltered outside air along with the conditioned air from the living space. We inspect return runs with a camera, seal accessible seams, and then clean the return path. If we don’t check the return, we’re not doing the job.
Supply Register Cleaning
Supply registers in older San Francisco homes are often painted over, rusted, or mounted in floors where decades of foot traffic have pushed debris into the boot. We remove each accessible register, clean the boot, and reinstall or replace the register face. Floor registers in pre-1940 homes are a particular collection point, and we typically find the heaviest accumulation there.
Trusted Brands We Service in San Francisco
We stock parts and filters for the brands most commonly installed across San Francisco’s housing stock, including Aprilaire filtration products and Guardsman components. If your system takes a specific filter size or an older blower motor, we can usually source it locally through our Bay Area parts distributors and avoid a multi-day wait. We also run Rotobrush and Abatement Technologies equipment in the field, which matters because older galvanized ducts need controlled agitation, not the brute force of a shop-vac wand.
Common HVAC Cleaning Problems We See in San Francisco Homes
- Musty odors from crawlspace returns. We recently serviced a 1920s Edwardian two-flat in the Inner Sunset where the homeowner complained of musty smells whenever the furnace kicked on. A camera inspection found the return duct in the garage crawlspace had a separated seam pulling in damp outside air and depositing a rust-colored film on the air handler. After sealing the seam and performing source removal with negative pressure and HEPA filtration, we photographed the before-and-after of the supply and return ducts to show the owner exactly what we removed.
- Rust contamination in fog-belt ductwork. Homes in the Sunset, the Richmond, and anywhere west of Twin Peaks sit in the fog zone most of the year. Unheated garages and crawlspaces condense moisture onto galvanized ducts, which then rust from the outside in. By the time a homeowner notices rust-colored dust at the registers, the duct seams have often failed and need sealing before cleaning makes sense.
- Decades of renovation debris in converted wall cavities. Pre-1940 Victorians and Edwardians almost always have return paths that were retrofitted through old wall chases and floor bays. Each renovation drops plaster, paint chips, and sawdust into those cavities. We vacuum out what’s accessible and document what we find so you know the system is actually clean, not just the registers.
- Per-vent pricing that doesn’t match the house. San Francisco’s multi-story homes have register counts that rarely reflect the true length or accessibility of the duct runs. A three-story Bernal Heights house with 12 registers often has shorter, more accessible ducts than a one-story Marina flat with 8 floor registers buried under hardwood. That’s why we quote one flat price per system after seeing the house, not a per-vent number that changes when the tech arrives.
Pricing for HVAC Cleaning in San Francisco, CA
A complete furnace and AC vent cleaning for a typical San Francisco home runs $450 to $900, with the final number depending on system size, accessibility, and how many returns run through crawlspaces. Furnace cleaning alone runs $300 to $550, and AC vent cleaning runs $150 to $350. Condenser cleaning for rooftop or side-yard units adds $100 to $200. The price we quote is the price you pay, written down before any work starts. It does not change at the door.
We never charge per vent or per register. In a three-story Victorian or a flat with floor registers, per-vent pricing is how companies turn a $199 teaser into a $900 invoice. We look at the system as a whole, quote you one number, and hand you the written price before a single duct is touched. Call (737) 727-2314 for a free estimate.
We Also Serve Cities Near San Francisco
Our San Francisco Bay Area crews handle HVAC Cleaning throughout the peninsula and across the bridges. In addition to every San Francisco neighborhood, we regularly serve Daly City, Brisbane, Sausalito, and South San Francisco. If you’re just over the county line, you’ll get the same flat-price-per-system policy and the same HVAC Cleaning in San Francisco standards we apply everywhere.
Serving San Francisco, CA - Our Local Coverage Area
We’re based in the San Francisco 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 San Francisco
Every 4 to 6 years is the honest answer for most San Francisco homes, and here’s why that differs from the national average. The city’s fog-cooled climate means furnaces run lightly compared to inland areas, so there’s less dry dust accumulation. But the moisture in crawlspace and garage returns creates rust and biological growth that can need attention sooner, especially in pre-1940 buildings with unsealed return paths. If your system smells musty when it kicks on, or if you’ve just finished a renovation, call us at (737) 727-2314 and we’ll tell you honestly whether cleaning is warranted. If it isn’t, we’ll say so.
Flat price per system, always. We quote one number for the furnace, AC vents, or both together, and that number is written down before any work starts. We never charge per vent or per register, because in San Francisco’s older multi-story homes, register count doesn’t reflect the real length or accessibility of the duct runs. The price we hand you is the price you pay. Call (737) 727-2314 for a written estimate.
It starts with a camera inspection so we know what we’re dealing with before we touch anything. Then we clean the supply and return ducts using source removal with negative pressure: a Rotobrush system agitates the debris, and a Nikro HEPA vacuum pulls it straight out of the system, not into your living room. We clean the blower, heat exchanger, and evaporator coil, seal accessible return seams, and then show you before-and-after photos of your own ducts. In a pre-1940 home, the inspection step matters most, because the right fix may be sealing, not brushing.
Yes, and in most San Francisco homes, that’s what we recommend. The furnace, the AC vents, and the ductwork all sit in the same airflow path, so cleaning one while leaving the others means the debris just redistributes. A full-system cleaning covers the blower assembly, heat exchanger, evaporator coil, supply registers, return grilles, and accessible duct branches in one visit. One flat price, one appointment, one set of before-and-after photos.
Because the smell isn’t coming from the dust you can see at the register. It’s coming from a failed return seam in a crawlspace or garage, pulling damp fog-air into the system, or from biological growth on the evaporator coil that sits damp between cooling cycles. In our experience across the Sunset, the Richmond, and the Inner Sunset, musty odors in older San Francisco homes are almost always a return-side problem. A camera inspection finds it fast, and sealing the seam usually solves the odor. Call (737) 727-2314 and we’ll inspect it.
Written by Omar Haddad, Owner at Cardinal Air Duct Cleaning, serving San Francisco and the surrounding Bay Area.




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