Flue relining
Sweep & inspection
Caps & crowns
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 Flue Liner Replacement: The Santa Clarita Owner’s Guide
Replacing a Gelco flue liner in Santa Clarita typically runs $2,200 to $4,800 installed, depending on the liner diameter, flue height, and whether we’re pulling an old stainless liner or working with a bare clay tile flue. We stock Gelco-compatible replacement components on our trucks and can usually complete the job in one visit once we’ve measured your existing liner. Flint Chimney Co Santa Clarita is an independent service provider, not affiliated with Gelco, but we install and work with their liner products alongside DuraFlex, HeatShield, Olympia Chimney, Famco, and Copperfield.
Most Santa Clarita homeowners discover a failed Gelco liner one of two ways: a Level 2 chimney inspection flags it (common during escrow on older Stevenson Ranch and Valencia homes), or visible rust flakes start appearing in the firebox. Either way, the fix is the same: remove the compromised section, verify the surrounding flue is sound, and install a correctly sized replacement. That’s the straight version. Below is everything you need to know before you call.
Key Takeaways
- Gelco liners fail from condensing flue gases eating through the stainless wall, usually at seams or weld points.
- Replacement is almost always less expensive than relining an entire chimney from scratch, but only if the surrounding masonry and clay tile are intact.
- We write the price before we start. The number you approve is the number on the invoice.
- Every Gelco replacement we install carries a written 365-day guarantee.
Which Gelco Models This Applies To
Gelco manufactures stainless steel chimney liner systems sold through chimney supply houses and HVAC distributors. The liners come in standard diameters, most commonly 4-inch through 8-inch, in both single-wall and insulated flex configurations. The compatibility question matters more than the model number. What matters is diameter, length, and whether the original install used Gelco’s rigid sections, flex sections, or a combination of both.
Here’s the gotcha we run into in Santa Clarita homes all the time: you cannot reliably identify a liner by eye. Stainless liners from Gelco, DuraFlex, and Olympia Chimney look nearly identical once they’ve seen a few seasons of heat. If the original installer left the product tag on the top plate or in the firebox, great. If not, we measure the inner diameter with a caliper and check the wall thickness. Gelco’s 316L alloy liners measure 0.005 to 0.006 inches in wall thickness on their standard residential flex, which is thinner than some competitors’ 0.006 to 0.008. That’s not a defect. It just means Gelco liners in homes that burn a lot of unseasoned wood tend to fail earlier than heavier-wall alternatives.
OEM versus aftermarket: Gelco parts are not sold direct to homeowners in most cases, and the company’s distribution runs through professional channels. What we do is match the replacement liner to the existing flue dimensions and the appliance’s BTU output, not just the brand stamped on the old tag. For an open-hearth fireplace, a 6-inch Gelco liner is a 6-inch liner. For a high-efficiency gas insert, we spec 316L stainless rated for condensing exhaust, which is a different material call entirely.
Styles & brands we work with





Signs Your Gelco Flue Liner Replacement Is Failing
- Rust flakes or brown staining in the firebox. This is the classic symptom. Condensing flue gas attacks stainless at its weakest points, usually the seam welds, and the resulting rust falls back down into the firebox. If you’re seeing rust, the liner wall is already compromised.
- A metallic or acrid smell during fires. Flue gases are supposed to stay inside the liner. When pinholes or seam cracks open up, those gases find their way into the chimney cavity and sometimes back into the living space. That smell is not creosote. It’s combustion byproduct that should be venting outside.
- White or chalky deposits on the liner’s exterior, visible from the top. This is a sign of condensation cycling, and in Santa Clarita it shows up more often on hillside homes in Stevenson Ranch and Castaic where overnight temperature swings are wider than on the valley floor.
- The liner has visible warping, buckling, or separated seams on camera inspection. A Level 2 inspection with a chimney camera shows this in about five minutes. Hank Delano has pulled more than a few photos from inspections where the liner looked intact from the top, but the camera showed a blown seam 15 feet down.
- Soot or creosote is accumulating on the outside of the liner instead of inside it. That means the liner is no longer containing the exhaust. You’re now working with an unlined chimney in practice, and that changes the safety equation entirely.
See the difference
Before
After
Before
After
Before
AfterReplacement Cost & What’s Included
In Santa Clarita, a Gelco flue liner replacement generally runs $2,200 to $4,800 installed. The range is driven by three things: flue height (two-story homes in Valencia cost more than single-story ranches in Canyon Country because we need longer liner sections), liner diameter, and whether we’re replacing a full run or a damaged section.
Every quote includes the liner material itself, removal and disposal of the failed section, installation labor, and a camera inspection of the finished install so you can see the new liner in place before we leave. We write the price before any work begins, and that number does not move unless the camera shows something we genuinely could not see from the initial inspection. If we find additional damage mid-job, we stop, show you the photos, and quote the add-on work separately. No surprises, no “while we’re in there” upsell. The written guarantee covers the replacement for one full year, and if a covered repair fails within that period, we return at no charge.
DIY or Call Us?
You can safely check a few things yourself: look for rust flakes in the firebox, check the top of the chimney for visible liner deterioration, and note whether fires smell different than they used to. What you should not do is attempt to pull or patch a stainless liner yourself. This is not a handyman project, and we say that for a specific reason: a compromised liner is already handling combustion gases at 400 to 1,000 degrees under normal operation. A repair that fails can allow those gases into wall cavities or the living space, and the first symptom of a carbon monoxide problem is often no symptom at all.
This is one of those jobs where the risk does not justify the savings. We’ve corrected more than a few homeowner patched liners in Santa Clarita where the fix was a sheet metal screw and some foil tape, and the result was worse than the original failure. Call us at (661) 430-6125. We’ll measure, inspect, and give you a written price for the work. If it can safely wait, we’ll tell you that too.
FAQs
A Gelco stainless liner typically lasts 12 to 20 years in Santa Clarita, though homes that burn unseasoned wood or operate fireplaces daily through winter tend to see failures earlier, especially in hillside areas where temperature swings accelerate condensation. We see Gelco liners from the mid-2000s reaching end of service life right now with some regularity. Call (661) 430-6125 for an inspection if yours is in that age range.
In most cases, no. Pinholes and seam cracks can sometimes be addressed with a stainless patch product if the damage is isolated, but the patch material and the original liner expand at different rates, and the repair usually fails again within a season or two. We recommend replacement when the liner wall is compromised in more than one spot. Call (661) 430-6125 and we’ll tell you honestly which situation you have.
Most Gelco flue liner replacements in Santa Clarita are completed in four to six hours on site, including removal of the old liner, installation of the new section, and a final camera inspection. Two-story homes and jobs requiring scaffolding add time. We quote the timeline in writing before work starts.
We stock common residential sizes (6-inch and 8-inch) on our trucks, along with compatible components from DuraFlex, HeatShield, Gelco, Olympia Chimney, Famco, and Copperfield. Uncommon diameters or custom lengths are ordered and typically arrive within a few business days. We’ll tell you at the estimate whether yours is a same-day job or a follow-up visit.
Clean flue, honest price – that’s the whole job. If your Gelco liner is showing signs of failure, call us at (661) 430-6125 for a free estimate and a straight answer on what you’re actually dealing with.
Written by Hank Delano, Owner, Flint Chimney Co Santa Clarita at Flint Chimney Co Santa Clarita, serving Santa Clarita and nearby areas.