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.
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Before
AfterGelco Flue Liner Replacement: The Greenwich Owner’s Guide
A Gelco flue liner replacement in Greenwich typically runs $1,800 to $3,400 installed, depending on the length, diameter, and what the camera finds when we pull the old one. We stock Gelco-compatible liners in the common residential sizes, and most swaps are done same day once the liner is on the truck. You’ll most likely land on this page because your home inspector flagged a liner issue during a pre-purchase inspection, or your oil or gas technician refused to sign off on a service call, or your previous sweep’s camera showed cracks, separation, or rot that changes what the flue can safely do. Any one of those is reason enough to get eyes back down the flue before winter.
Which Gelco Models This Applies To
Gelco makes two liner families you’ll see in Greenwich homes: the smooth-wall rigid liners found in newer direct-vent and gas applications, and the flexible stainless relining kits used inside existing masonry chimneys. The compatible replacement part depends on which one you have, and the only reliable way to know is to match the inside diameter, not just the brand name. You’ll find a data tag near the top of the liner or in the appliance manual, but tags go missing in attics and basements all the time. We measure. In backcountry Greenwich homes that run oil-fired boilers with larger flue diameters, we see a lot of 6-inch and 7-inch Gelco flex liners. The smaller 4-inch and 5-inch runs are more common in Compo-Ong and Old Greenwich colonials converted to gas. One compatibility gotcha: Gelco’s rigid smooth-wall sections don’t always interchange with flex connector parts from other suppliers, so mixing brands mid-run is how you get misaligned joints and leaks that a camera catches a year later. We quote Gelco OEM, or a quality aftermarket equivalent from DuraFlex or HeatShield when it matches the existing run and the appliance’s venting requirements. Level Two Chimney Greenwich is an independent service provider, not affiliated with Gelco. The liner choice is always in writing before work starts, with the brand, gauge, and diameter spelled out.
Signs Your Gelco Flue Liner Replacement Is Failing
- Rust flakes or pinholes at the cleanout. Stainless liners fail at welds and seam points first. If you pull off the cleanout door and see rust scale, that’s not surface rust, that’s the liner wall losing material from the inside out. A camera scan confirms where the section has gone.
- Condensation streaks on the exterior chimney wall. In Greenwich’s humid summers and wet winters, a leaking liner lets moisture condense behind the masonry. You’ll see dark vertical staining on the chimney face, often worse on the north side. The water is climbing the liner gap, not the brick itself.
- Exhaust smell in the house, especially on startup. A perforated or separated liner can’t carry combustion gases out. The first cold snap after Thanksgiving is when we get these calls, because the appliance cycles more often and the leak expands.
- Visible gaps or sag at the top connection. From the roof line, the liner should run straight and tight to the termination cap. A sag means the support or the top clamp has given way. In some Greenwich homes with older caps, the liner was never properly secured at the crown, and it’s been slowly pulling apart for years.
- Gas or oil service tech flags it in the service report. This is the one we trust most. A licensed tech has a combustion analyzer in your flue, and the readings are what they are. If the note says “flue gas spillage” or “liner not serviceable,” the liner is the repair, not a recommendation.
BeforeAfterReplacement Cost & What’s Included
In Greenwich, a straightforward Gelco flue liner replacement with roof access runs $1,800 to $2,600 for most single-family homes. Longer runs, steeper roof pitches, or a liner that’s degraded to the point it comes out in pieces will push that to $3,000 to $3,400. The written price covers the liner itself, the top plate and termination, removal of the old liner, installation, and a camera re-scan after the new liner is in. Corrine Halstead’s crew has pulled liners out of homes across Greenwich long enough to know when a “simple swap” is going to turn into a masonry repair at the crown, and we’ll flag that before anyone starts. You don’t get a quote that changes by the hour. You get a written scope, a written number, and a written warranty on the work, all before a brush touches the chimney. A documented photo record of the finished liner comes with every job, not as an add-on.
DIY or Call Us?
Here’s the honest line. You can safely check the cleanout yourself: open the door, look for rust scale, smell for anything acrid, and shine a flashlight up. But the moment you think about pulling or replacing a flue liner yourself, stop. A flue liner runs inside a masonry or prefab chase, and it’s under tension at the connections. A dropped section, a sliced hand on a steel edge, or a liner that fails to seat properly at the appliance connection puts exhaust gas where it can hurt people, not where it can vent. None of that is a weekend project. We’ve seen DIY liner jobs in Greenwich that had to be pulled and redone because the sizing was off by a quarter inch, and the homeowner paid twice. If you suspect the liner is done, the camera tells us in fifteen minutes what the fix is. Call (516) 399-5497 and we’ll put a written number on the table before anything else happens.
FAQs
A properly installed Gelco stainless flue liner in Greenwich lasts 15 to 25 years. The real-world spread depends on what it’s venting. Oil-fired appliances produce more acidic condensate and eat liners faster, especially in the damp coastal air we get down toward Byram and Cos Cob. Gas liners run cooler and last longer, but any liner that’s been in service since the 1990s is on the back side of its useful life. If you don’t know the installation date, a camera inspection is the only way to tell what’s left. Call (516) 399-5497 and we’ll schedule one.
Minor repairs, like a loose top clamp or a small section replacement at the crown, are sometimes possible. A liner with multiple rust-through points or separation mid-run is not worth spot-patching. Stainless liners fail progressively, and a patched section is often just the next failure point waiting. We’ll show you the camera footage and tell you plainly if a repair buys you five years or if a replacement is the only answer that doesn’t strand you mid-winter. A written price for either path is always provided before work starts.
Most Gelco flue liner replacements in Greenwich are done in one day, four to six hours on-site. The variables are roof access, the condition of the old liner on removal, and whether the crown or top plate needs masonry work before the new liner seats correctly. We tell you the time estimate on the written quote, and we text you when the assigned technician is on the way.
We stock Gelco-compatible liners in the common residential diameters (4-inch, 5-inch, 6-inch, 7-inch) on the truck and in our Greenwich yard. Unusual lengths or larger commercial diameters may be pulled from the Haven supply network, which carries Gelco, DuraFlex, HeatShield, Olympia Chimney, Famco, and Copperfield. When we can’t complete the swap same day, you’ll know before we leave, not after we’ve opened the wall.
Written by Corrine Halstead, Owner, Level Two Chimney Greenwich at Level Two Chimney Greenwich, serving Greenwich and nearby areas.