Level 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 Trenton Owner’s Guide
Gelco flue liner replacement in Trenton typically runs $1,800 to $3,400 installed, depending on liner diameter, chimney height, and whether the existing liner pulls out cleanly or has to be cut out in sections. We stock Gelco-compatible replacement liners in common diameters from 3 to 6 inches and can usually inspect, measure, and schedule installation within a few days. Most Trenton homeowners discover their liner has failed during a routine sweep when our camera finds gaps, corrosion, or creosote buildup behind a separated seam.
Which Gelco Models This Applies To
Gelco built stainless steel chimney liners in several series over the years, and the replacement part you need depends on what is already in your flue. The older Gelco 316Ti flexible liners, common in Trenton homes from the 1990s and early 2000s, carry a part number stamped on the top collar or termination cap. Newer Gelco 304 and 316L rigid sections have a different wall thickness and coupling system. We match by measuring the inner diameter at both the top and bottom of the flue, since settling in older Trenton masonry can create a slight taper that matters for fit.
We are not affiliated with Gelco. We source replacement liners from the same mills that supplied their original stock, which means you get the same alloy grade and wall thickness without paying for a logo. For most Trenton installations, a quality aftermarket 316Ti flexible liner with a lifetime warranty outperforms hunting down discontinued Gelco OEM stock. The one compatibility gotcha: Gelco’s original termination caps used a proprietary twist-lock that does not mate with standard aftermarket collars. We either adapt the existing cap or replace it with a universal model that fits better and cleans easier.
Signs Your Gelco Flue Liner Replacement Is Failing
- Smoke or odor in the house during a fire. A separated seam or corrosion hole in your Gelco liner lets exhaust escape into the chimney cavity instead of channeling it up and out. In Trenton’s older homes with balloon framing, that smoke can travel through wall cavities before you ever smell it at the fireplace.
- Flakes of rust or stainless steel debris in the firebox. The 316Ti alloy resists corrosion well, but if your liner was installed without proper insulation or if the chimney crown leaked for years, the outer surface deteriorates from the outside in. What falls into your firebox is often the first visible warning.
- White or powdery efflorescence on exterior brick. Exhaust gases carrying moisture through a liner breach condense against the cooler masonry, drawing salts to the surface. We see this pattern frequently on the north-facing sides of Trenton rowhouses where the brick never fully dries.
- Damper frame warping or rusting unusually fast. A failing liner concentrates heat and corrosive gases lower in the flue than designed. The damper, being the first metal component above the fire, takes the brunt of that abuse.
- Your sweep flags “suspected liner breach” on camera. Our Level-2 inspection cameras reveal the actual condition: gaps at joints, thinning wall sections, or creosote accumulation on the outside of the liner where no creosote should ever reach. Photos you can see, a plain-English verdict.
Replacement Cost & What’s Included
| Scope | Typical Range in Trenton |
|---|---|
| Straight replacement, 3″-5″ flexible liner, single-story | $1,800 - $2,400 |
| Replacement with offset or multiple bends, two-story | $2,400 - $3,000 |
| Rigid liner system, 6″, with insulation and new termination | $2,800 - $3,400 |
| Chimney crown repair or rebuild (often needed) | $400 - $900 additional |
What drives the range: liner diameter and length, whether we can pull the old liner in one piece or cut it out through a mid-chimney access point, and whether the chimney crown or top plate needs rebuilding to support a new termination properly. Every estimate includes the liner, insulation wrap, top and bottom connections, and a new cap or termination. We quote the full number before we start. No surprises on the bill. All liner work carries our 90-Day Done Right Promise, in writing, no arguing.
DIY or Call Us?
There is exactly one thing a homeowner can safely check: shine a flashlight up the flue from the firebox and look for obvious gaps, heavy rust staining, or daylight where the liner should be continuous. Do not attempt to climb the roof to inspect the top. Do not attempt to pull or install a flue liner yourself.
Flue liner replacement involves working at height on a roof, handling sharp stainless steel edges, and properly insulating and supporting a liner so it does not sag, separate, or create a new fire hazard. The National Fire Protection Association 211 standard governs every detail of the installation. A liner installed without proper insulation clearance can overheat surrounding framing. A liner cut too short or coupled incorrectly can leak carbon monoxide into living spaces. We have found DIY liner attempts in Trenton that looked fine from the bottom and were completely detached at the top. If the chimney’s not right, the fire’s not safe. That’s the whole job. Call (856) 519-0832 and we will inspect, measure, and quote with no pressure.
FAQs
A properly installed 316Ti stainless liner with insulation should last 20 to 30 years in Trenton’s climate, though salt air exposure from the Delaware River valley accelerates exterior corrosion on uninsulated runs. Annual inspection and cleaning will get you the full lifespan. Call (856) 519-0832 to schedule - estimates are free.
Small, accessible gaps in a relatively new liner can sometimes be patched with a compatible stainless sleeve, but most Gelco liners we encounter in Trenton are past the point where patching makes sense. Once corrosion is visible from the inside, the outside is worse. We will show you the camera footage and tell you honestly whether repair or replacement is the square deal.
Most Gelco liner replacements take one full day, assuming the existing liner pulls out without fighting and the chimney crown is sound. If we need to cut out a seized liner in sections or rebuild the crown, we may need a second day. We complete most jobs in a single visit, and we will tell you during the estimate if yours looks like an exception.
We stock 316Ti flexible liners in diameters from 3 to 6 inches, along with the insulation, termination caps, and adapters needed for most Trenton installations. For unusual sizes or rigid systems, we order from our supplier and typically have material within two business days. We do not send you hunting for parts.
Ready to get your Gelco flue liner sorted? Call (856) 519-0832 any time - a live person answers, 24 hours a day, 7 days a week. We will set up a free estimate, run the camera, and give you the plain facts on what your chimney needs. Done right, and we stand behind it.
Written by Russell Haines, Owner, Hearthstone Chimney Co. at Hearthstone Chimney Co., serving Trenton and nearby areas.





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