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.
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AfterFast, Reliable HVAC Cleaning Across Half Moon Bay
HVAC cleaning in Half Moon Bay costs $425 – $780 for a typical single-family home, depending on square footage and how much salt air and fog have worked into the system. Our HVAC Cleaning team services the entire Coastside from Miramar to Princeton-by-the-Sea, usually scheduling within five to seven business days. We know what coastal humidity does to duct runs here. Call (737) 727-2314 and we’ll get you a written price before anyone touches a single register.
Why Half Moon Bay Homeowners Choose Cardinal Air Duct Cleaning
Our reputation in Half Moon Bay comes from showing coastal homeowners what’s actually inside their ducts before they pay for anything. Omar Haddad built our HVAC Cleaning in Half Moon Bay service around camera inspections and before-and-after photos, because fog-belt homes hide problems inland houses never see. We arrive with Rotobrush brush systems and Nikro HEPA extraction units, not a truck-mounted shop vac. Every booking includes a live trackable arrival window, the written price, and the 365-Day Done Right Promise: if the work isn’t right within a year, we return and correct it at no charge.
Homeowners from El Granada to the Frenchman’s Creek neighborhood call us because a live person answers the phone 24/7 and the technician’s name, photo, and background check are sent before the door opens. We’re independently owned, part of the Relay Home Co. family founded in 2005, and held to The Relay Visibility Guarantee on every job. That means no vague estimates, no four-hour arrival windows, and no price that shifts once the van is parked.
AC Vent Cleaning in Half Moon Bay
Air Duct Cleaning - Half Moon Bay typically includes AC vent cleaning at $120 – $240 as part of a full system clean, and it matters more here than inland because fog-season condensation leaves dust stuck to vent louvers instead of loose. We pull each vent, wash the grilles, and vacuum the boot and first few feet of the run. The vent itself is only part of the story though, and a vent-only upsell without the supply and return runs is half a job.
In Half Moon Bay, we’re looking for salt film on the backside of vent louvers. That film is hygroscopic, meaning it pulls moisture from the air and holds it against the metal. It also catches dust that would otherwise blow through. On older Main Street homes and newer bluff-side builds alike, we see the same pattern: supply vents facing the ocean side of the house collect more coastal grime than the leeward side. We’ll note that in your after photos so you can see the difference.
Vent Boots and Collar Seals
Behind the vent, the boot and collar are where leaks start in Half Moon Bay’s salt air. Galvanized collars corrode at the seam, pinholes form, and conditioned air pushes into the wall cavity instead of the room. We check every boot during a clean and seal minor gaps on the spot.
Supply vs. Return Vent Work
Supply vents push air out; return vents pull it in. Returns pull harder against the coastal grime because they’re drawing air across whatever the house collects. We price both together because cleaning only the supplies in Half Moon Bay leaves the returns as a damp, dirty source feeding your air handler.
Furnace Duct Cleaning in Half Moon Bay
Furnace duct cleaning in Half Moon Bay costs $350 – $680 for the full duct run, and fog-belt homes need the whole path addressed, not just what’s visible. We start with a camera inspection of the supply and return plenum, then agitate each run under negative pressure so loosened debris goes straight into the HEPA unit, not back into the living room. In coastal homes here, we’re not just chasing dust bunnies. We’re removing the damp organic film that supports microbial growth before it becomes a permanent musty odor.
Return Runs and the Coastal Damp Problem
Return ducts in Half Moon Bay sit cooler than supply runs in summer when the fog rolls in and the house isn’t calling for heat. That temperature drop plus high dew points means condensation inside the return metal. Condensation plus dust equals growth. We pull return grilles, clean the full run, and document it, because this is the part of the system inland competitors rarely touch.
Air Handler and Blower Compartment
The air handler is where Half Moon Bay’s damp air pools first when the system cycles off. Blower wheels, the evaporator coil, and the drain pan all sit in a dark, humid box. If the blower motor is pushing air across a moldy coil, cleaning the ducts alone won’t fix the smell. We clean the handler compartment and blower as part of every furnace duct cleaning here.
Heat Exchanger and Coil Treatment
On gas furnace systems, a dirty heat exchanger and evaporator coil slow airflow and force the system to run longer, which pulls in more coastal air. We clean both, then apply a coil treatment that helps prevent the biofilm from reattaching. This is real source removal, not a spray-down.
Trusted Brands We Service in Half Moon Bay
We stock filters and service parts for most brands you’ll find in Half Moon Bay homes: Carrier, Trane, Lennox, Rheem, Goodman, York, and Mitsubishi. If you’re on the coast and your air handler needs a specific filter frame or drain pan, we can usually source it fast. Our techs work on all of them, and Rotobrush agitation plus Nikro HEPA extraction is brand-agnostic. It’s the same professional-grade approach whether your system is a 15-year-old Carrier or a newer Mitsubishi mini-split.
Common HVAC Cleaning Problems We See in Half Moon Bay Homes
- Fog-fed musty smell on system startup. The blower kicks on and the room fills with a damp, earthy smell for the first minute. That’s growth on the coil or in the return run, fed by half the year of fog and not by neglect. Inland homes on the same filter schedule never develop it.
- Salt-corroded vent boots and collars. Galvanized metal plus marine air equals slow corrosion at seams and screw holes. We find leaking collars inside walls and under floors in homes from Frenchman’s Creek to the Avenida around downtown, and on enough of them that we check every boot during a clean.
- Dusty supply vents on the ocean-facing side only. One side of the house gets more coastal grime than the other because the prevailing wind does the work. You’ll see heavier buildup on the west and northwest vent faces. We’ll show you the before photos.
- Air handler compartments with standing moisture on the coast side of Highway 1. Humid air from the marine layer enters the return, cools in the handler, and water collects in the blower compartment and drain pan. These systems grow problems before the ducts ever show it. Our camera inspection documents the starting condition so you can see exactly what we cleaned.
Pricing for HVAC Cleaning in Half Moon Bay, CA
In Half Moon Bay, a full HVAC clean with air handler, blower, evaporator coil, and all duct runs typically runs $425 – $780. The lower end covers a single-zone home under 1,800 square feet with accessible ducts and minimal coastal buildup. The upper end is a two-story or hillside home with multiple returns, older metal ducts, and the kind of salt-and-moisture film that takes real agitation time to remove. Furnace duct cleaning alone runs $350 – $680. AC vent cleaning as part of a full clean is $120 – $240; we don’t sell it as a standalone because vent-only work in Half Moon Bay leaves the source untouched.
Omar Haddad’s policy is a written price before any work starts, and that price does not change at the door. Call (737) 727-2314 for a free estimate with a specific number for your home’s square footage and system.
We Also Serve Cities Near Half Moon Bay
Our crews cover the whole San Francisco Bay Area peninsula coast. If you’re in Half Moon Bay, we’re already in your neighborhood. We also serve El Granada, Burlingame, Millbrae, and Belmont, plus the surrounding Coastside communities. If you’re a few minutes up Highway 92 or down Highway 1, call (737) 727-2314 and we’ll get you scheduled.
Serving Half Moon Bay, CA - Our Local Coverage Area
We’re based in the Half Moon Bay 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 Half Moon Bay
Because Half Moon Bay sits in a fog belt where summer dew points run 10 to 15 degrees higher than Burlingame or Millbrae, so duct interiors here stay damp for hours after the fog burns off. That persistent moisture lets microbial growth take hold in supply runs while inland homes stay dry enough to avoid it. The fix is not a scented spray. It’s removing the damp organic film and treating the metal so growth can’t reattach. Call (737) 727-2314 for an inspection and a written price.
No. A fogging ‘sanitiser’ or ozone treatment leaves the biofilm and salt film in place because it never removes the source. It masks the smell for a few weeks at best, and in Half Moon Bay’s fog-belt humidity the growth returns once the fog pattern does. Genuine source removal means mechanical agitation, HEPA extraction under negative pressure, and a coil treatment applied after the surface is clean. We’ve pulled the duct runs on a home off Kelly Avenue near downtown Half Moon Bay and found the return-side galvanized runs coated in a dark, damp film with visible microbial spotting that an inland house on the same filter schedule never develops. After camera inspection and agitation tools knocked the growth loose under negative pressure, our tech ran a HEPA filtration unit while cleaning and sealed a corroded boot where salt air had eaten through the collar. The owner’s musty smell on blower startup cleared once the source was removed rather than masked. Call (737) 727-2314 for an exact quote.
Salt-laden marine air leaves a fine hygroscopic film inside galvanized ductwork that holds moisture against the metal instead of letting it evaporate. That film then catches dust and organic particles, which feeds the same microbial growth that causes musty smells. The salt also corrodes boots, collars, and the air handler drain pan. Homes west of Highway 1, from Miramar south to Princeton-by-the-Sea, show this faster than homes east of the highway. We inspect for corrosion during every clean and seal what we can on the spot. Call (737) 727-2314 to schedule a camera inspection.
We clean to NADCA standards: source removal through mechanical agitation and HEPA-rated negative-pressure extraction, with all access points sealed and the air handler and blower compartment included. We document the work with before-and-after photos so you can see what was actually removed. The 365-Day Done Right Promise covers every job in Half Moon Bay.
In Half Moon Bay, we generally recommend a MERV 11 or 13 filter changed every 60 to 90 days during fog season and every 90 days the rest of the year. Higher MERV ratings catch more of the fine coastal particulate, but they also restrict airflow, so don’t go above MERV 13 without confirming your system’s static pressure. A pleated filter beats a fiberglass one in coastal air, and if you’re running the system more often to fight humidity, check the filter monthly. Call (737) 727-2314 for a free estimate and we’ll recommend the right filter for your system and your home’s location on the coast.
Written by Omar Haddad, Owner at Cardinal Air Duct Cleaning, serving Half Moon Bay and the surrounding Coastside. Part of the Relay Home Co. family, founded 2005.