Sweep & inspection
Caps & crowns
Flue relining
Masonry repair
Gas fireplace serviceLevel 1 sweep and inspection to the NFPA 211 annual standard - flue, crown, cap, and flashing checked and photographed
Chimney sweep logs do not sweep chimneys. They loosen some creosote - which then falls where a brush and vacuum still have to collect it.
Gelco Chimney Cleaning in San Marcos, TX | Hadley Chimney Austin
We’re an independent chimney service that cleans and maintains Gelco prefabricated systems throughout San Marcos, and the short answer is yes, we service every Gelco model we’ve run across in Hays County. What makes our work different here is simple: we know how San Marcos humidity and east-side clay foundations stress these units in ways the factory manual never anticipated. Call (361) 603-5116 for a Gelco inspection, cleaning, or repair estimate. If you own a Gelco fireplace or chimney pipe and you’re not sure when it was last actually looked at, this page will tell you exactly what we check and what it costs before you spend a dime.
Why San Marcos Residents Choose Us for Gelco Service
Gelco prefab chimneys aren’t like masonry fireplaces. They’re engineered systems with specific clearances, specific pipe diameters, and specific failure points. The good news: our technicians have been pulling caps and scoping liners on these units for over two decades, so the common problems show themselves fast. Cory Mitchell, our owner, came up through the HVAC and building systems program at LA Trade-Tech before he planted his flag in chimney work, and he’s the kind of guy who won’t quote you a repair until he’s shown you the camera photo of what’s actually wrong. For Gelco sales & service, that experience matters because these units age in predictable but locally specific ways. We carry OEM-compatible Gelco pipe sections and source genuine parts when replacement is needed, and we’re local to San Marcos service area zip codes, so scheduling doesn’t take three weeks.
Styles & brands we work with





Common Gelco Chimney Cleaning Problems We Solve in San Marcos
- Rusted galvanized outer casings. San Marcos’s humid subtropical air sits against shaded north-facing flues and works into the galvanized steel over time. We regularly see Gelco SC and 1700 series outer pipe with rust blooms around the locking bands, and if left alone, the casing eventually perforates and lets rain into the chase.
- Buckled stainless inner liners. Long idle stretches between fires let creosote harden inside the flue. When someone finally lights a hot fire, the thermal shock hits that hard creosote and the underlying stainless expands unevenly. On Gelco 2100 high-temperature pipe, this shows up as a visible warp at the seam when we scope it.
- Loose firestop assemblies. East-side San Marcos homes from the 1960s and 70s often sit on clay-tile foundations that shift with soil moisture swings. That movement transfers into attic framing, and over decades, Gelco firestop collars pull away from the rafter line. The gap lets warm air into the attic and breaks the UL-listed clearance envelope.
- Corroded rain caps and terminations. Weld points at the cap are where moisture attacks first, and in San Marcos that process runs faster than in drier Central Texas towns. A failed cap lets water run straight down into Gelco G-series refractory panels, which spall and crack when they get wet and hot in the wrong order.
- Hardened creosote that standard brushes won’t touch. The mild winters here mean fireplaces get used ten or twelve times a season, not nightly. Creosote builds, cools, builds again, and eventually glazes over. We use rotary whip systems and chemical treatments to break it down on Gelco flues without scoring the stainless inner wall.
Gelco Service in San Marcos: What Local Conditions Mean for Your Equipment
Here’s the San Marcos-specific thing that most generic Gelco pages will never tell you. On the east side, in neighborhoods like the ones off Old Bastrop Highway and along Craddock Avenue, the original Gelco installations from the 1960s and 70s weren’t always built with the roof penetration details you’d see today. Roofers and framers of that era often ran factory-built flues through low-slope surfaces with minimal flashing, and the clay-tile foundations underneath settle a little differently every wet-dry cycle. So the cap sits slightly out of square, the flashing pulls open at the caulk line, and moisture finds the galvanized casing. We pulled a cap off a Gelco SC chimney on a split-level over near the San Marcos River on Craddock Avenue during our Chimney Sweep in San Marcos and found the inner liner separated at a seam two feet above the firestop. The homeowner had lit two fires all winter. Hard creosote trapped moisture for months, the stainless warped, and the draft quietly stopped working. We replaced the affected pipe section with a Gelco-compatible segment and installed a proper multi-flue cap. That’s not a Kyle problem or a New Braunfels pattern. That’s San Marcos east-side construction and San Marcos humidity working together.
Gelco Models & Products We Service in San Marcos
Our crews handle Chimney Repair in San Marcos for the full range of Gelco systems installed across Hays County. That includes the Gelco SC series air-cooled chimney, the Gelco G series factory-built fireplace, Gelco 1700 series chimney pipe, and Gelco 2100 series high-temperature pipe. When a genuine Gelco pipe section or termination is available through our parts channels, we source it. For consumables like rain caps, flashings, and locking bands, we use quality aftermarket parts that match the original outside diameter and rated clearances, not whatever generic piece is closest on the truck. We keep common Gelco-compatible pipe lengths and caps in local stock for faster turnaround in San Marcos, so a rusted termination doesn’t have to leave your flue open for a week while parts ship.
See the difference
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AfterGelco Service Pricing in San Marcos
What you’ll pay for Gelco chimney work in San Marcos depends on what we find, but the baseline numbers are predictable. A standard cleaning and visual inspection on a Gelco prefab system typically runs $199 to $349 in this market. A Level 2 camera inspection, which we recommend for any Gelco unit that hasn’t been scoped in three years or has signs of rust or draft issues, generally runs $249 to $399. Cap replacement lands between $150 and $450 depending on the flue diameter and roof access. If we find a warped inner liner or separated seam, pipe section replacement starts around $400 and goes up based on how many sections and roof complexity. Every estimate is free, and you get the written price before we pick up a brush. Call (361) 603-5116 and we’ll get you a number.
Serving San Marcos, TX - Our Local Coverage Area
We’re based in the San Marcos 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 – Gelco Chimney Cleaning in San Marcos
Rust on Gelco systems comes from trapped moisture, not heavy use. In San Marcos, the humid subtropical air keeps the inside of the flue damp, and when creosote hardens during long idle periods, it holds that moisture against the stainless liner. The galvanized outer casing catches ambient humidity and rusts at the seams, especially on north-facing runs that never dry out. The fix is usually a cap replacement and a cleaning that removes the moisture-trapping creosote, but if the inner liner has warped, you’ll need pipe sections replaced, not just cleaned. Call (361) 603-5116 and we’ll scope it and show you exactly what’s rusting.
Yes. We can inspect and clean a Gelco system from the roof and firebox without entering living spaces. You’ll get photo documentation of the flue interior, the cap, and the firebox condition, plus a written report you can use for lease compliance or insurance renewal. Many San Marcos property managers schedule these annually. Call (361) 603-5116 to set one up.
Refractory panels in Gelco G-series fireplaces are the insulated panels that line the firebox and reflect heat. A cracked panel is a real hazard because it exposes the metal firebox shell to direct flame, and over time that can warp the firebox. It also means heat is reaching materials that weren’t rated for it if the crack goes deep. We don’t always have to replace every panel; sometimes one section can come out. Call (361) 603-5116 and we’ll quote panel replacement with the right Gelco dimensions.
When creosote glazes over in a Gelco flue, standard wire brushes just polish it. We use a rotary cleaning whip with flexible nylon strands that spin at high speed inside the liner, plus a glazed creosote remover when the build-up is heavy. It breaks down the tar layer without scoring the stainless inner wall, which matters on Gelco because a scratched liner holds moisture even more readily here in San Marcos. Call (361) 603-5116 if you haven’t had the flue scoped in a few years.
We do, and those east-side 1960s and 70s homes are some of the most common Gelco calls we handle. The clay-tile foundation movement affects the whole chase, not just the flue, and we know to check firestop alignment and flashing fit on those houses specifically. Foundation settling is normal there, but the chimney clearance envelope still needs to hold. Call (361) 603-5116 and we’ll take a look at yours.
Service Areas Near San Marcos
We run Gelco service calls throughout Hays County and into the surrounding area. If you’re in Austin, we’re close by, and we also cover Cedar Park and Lockhart. Check our Gelco service in Austin page or our Gelco service in Cedar Park page for area-specific details. San Marcos homeowners get the same live-arrival tracking and written pricing as anyone else we serve.
Book Your Gelco Service in San Marcos Today
You don’t need to guess what’s happening inside your Gelco flue. Call (361) 603-5116 and we’ll set up a cleaning or Level 2 inspection, get a technician to your San Marcos home with a tracked arrival window, and show you the photos before we recommend anything. Free estimates, written prices, and a real person on the phone.
Written by Cory Mitchell, Owner at Hadley Chimney Austin, serving San Marcos and surrounding areas since 2003.