Duct Sealing in San Jacinto - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across San Jacinto

We dispatch to San Jacinto from our Inland Empire office, and most days we’re on State Street or Ramona Boulevard within the hour. Our crews know the difference between a 1989 stucco tract off Esplanade Avenue and a single-wall farmhouse on the east side near the old agricultural parcels, because the ductwork inside tells two different stories. If your system blows hard but the registers barely whisper, or your summer power bill climbs while the back bedrooms stay hot, you probably don’t need more cleaning. You need sealing. Call us at (361) 326-5060 for a free estimate.

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Why Hollis Air Duct Cleaning Is San Jacinto’s Preferred Duct Sealing Company

We’ve been working in San Jacinto long enough to know which homes have original galvanized ductwork from the 1970s and which tracts went up during the 1990s boom with flexible runs that sag in the attic. That history matters because it changes what we find and how we fix it.

Our technicians are background-checked and uniformed, and they arrive inside the quoted window. The price is written down before any work starts, and it does not move at the door. Every duct sealing job carries our 365-Day Done Right Promise in writing: if the seal fails or the airflow problem returns within a year, we come back and make it right at no charge, including a free second visit.

Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to schedule.

HVAC Duct Sealing in San Jacinto

HVAC Duct Sealing in San Jacinto is often the real fix for homes that have been cleaned repeatedly but still suffer weak airflow, hot rooms, and rising energy bills. The job involves finding every leak, gap, and disconnected joint in your supply and return runs, then sealing them with mastic and mesh or mechanical fasteners that hold under pressure. In San Jacinto, we see a lot of homes where the ducts were “sealed” years ago with duct tape that has cooked to dust in the attic, or where flex runs have pulled loose from collars and are leaking conditioned air into the wall cavities.

Most San Jacinto homeowners need sealing when they notice uneven temperatures between rooms, dust blowing from registers right after cleaning, or a spike in summer cooling costs. The work typically runs $450 to $1,200 for a whole-home seal, depending on accessibility and how much of the system needs attention. Homes with legacy evaporative cooler ducts sharing space with modern HVAC often land at the higher end because we have to seal or cap the abandoned runs first.

When Cleaning Isn’t Enough

A rotary brush system and negative-air machine can remove debris, but they can’t close a gap. If your ducts were cleaned last year and the dust is back, the problem is likely infiltration through unsealed joints, not dirty ducts. We check this with a pressure pan test before we quote any sealing work.

Mastic vs. Tape in Local Conditions

San Jacinto’s attic heat destroys standard duct tape in two to three summers. We use water-based duct mastic rated for 250°F, reinforced with fiberglass mesh on joints and collars. It stays flexible and bonded for years, not seasons.

Duct Repair in San Jacinto

Duct Repair in San Jacinto often starts with a crushed flex run, a rusted-out galvanized section, or a joint that has been “fixed” so many times it’s become a debris trap. We don’t patch over problems. We cut out failed sections, splice in new flex or sheet metal, and seal the repair properly so it matches the rest of the system. In San Jacinto’s older homes, especially the single-wall farmhouses and early stucco tracts, we regularly find original ductwork that has never been touched since installation.

Homeowners usually call us for repair when they hear whistling from the walls, smell musty air from specific registers, or find one room that never reaches temperature. Duct repair in San Jacinto typically costs $280 to $850 per run, with whole-system replacements for older galvanized runs running $1,800 to $3,500. We always inspect with a camera first so you know exactly what failed and why before we quote.

Crushed Runs Behind Air Handlers

This is the most common hidden failure we find in San Jacinto. The flex duct gets kinked during a filter change or a prior service call, and nobody notices because it’s behind the unit. We run a borescope to confirm, then replace the crushed section with properly supported flex or rigid pipe.

Rusted Galvanized in Older Homes

Original galvanized ductwork from the 1970s and 1980s corrodes from the inside out in San Jacinto’s dry heat. Once the wall metal is perforated, sealing won’t hold. We replace with insulated flex or sheet metal, sealed to current standards.

Trusted Brands We Service in San Jacinto

We carry sealing products and filtration components from Honeywell, Aprilaire, and Guardsman on our San Jacinto trucks, so most repairs don’t wait for a parts run. For source removal before sealing, we use Rotobrush rotary brush systems and Nikro negative-air machines, the same equipment commercial crews run in hospitals and schools. If your system uses Abatement Technologies HEPA filtration, we stock compatible media and can integrate it into the sealed duct layout. Parts availability matters here because San Jacinto’s summer heat doesn’t give you a week to wait on a warehouse shipment.

Common Duct Sealing Problems We See in San Jacinto Homes

• Legacy evaporative cooler vents left open alongside modern HVAC. Santa Ana winds push dust and ash through these abandoned vents, bypassing your sealed supply and return ducts entirely. We cap or seal them with mastic and a solid register cover so the infiltration stops.
• Mineral scale on galvanized wall metal from decades of hard water and cooler runoff. Standard mastic bonds to dust, not scale. We wire-brush the crust off first, then seal. Skip this step and the mastic flakes off within a season.
• Taped flex runs near air handlers that were “repaired” after prior cleans. The tape cooks and the flex collapses into a lint pathway, leaking supply air into the attic chase instead of your bedrooms. We replace the failed section and support it properly.
• The valley grit on east-side homes near old agricultural parcels. This cotton-gin-debris-and-silica blend from Santa Ana winds packs into joints and collars. A standard vacuum pass won’t touch it. We use agitation tools under negative pressure to break it loose, then seal clean metal.

Pricing for Duct Sealing in San Jacinto, CA

We Also Serve Cities Near San Jacinto

Our crews work throughout the San Jacinto Valley, including San Jacinto and neighboring Hemet, Nuevo, Homeland, and Banning. If you’re in the valley and your ducts need attention, we cover your area. Our Duct Sealing team coordinates dispatch from the Inland Empire office to keep response times short across the region.

FAQs About Duct Sealing in San Jacinto