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 Peabody Owner’s Guide
If you’ve got a Gelco flue liner that’s cracked, warped, or rusted through, we stock Gelco-compatible replacement liners on the truck and can usually have the new one installed in a single visit. Most Gelco flue liner replacements in Peabody run between $1,850 and $3,400 installed, depending on the liner diameter, the height of your chimney, and whether the old liner puts up a fight coming out. Owners typically discover the problem one of two ways: either they see rust flakes and flue tile chips in the firebox, or their oil burner starts short-cycling and the service tech traces it back to poor draft through a failed liner. Either way, the liner is the chimney’s working part, and when it goes, it goes because the acidic flue gases finally ate through it.
We’re an independent service provider in Peabody, not affiliated with Gelco directly. That matters because we’re not here to sell you a brand. We’re here to tell you what your chimney actually needs, and if the liner doesn’t need replacing, Wendell will tell you that plainly. If it does not need doing, he will tell you that too.
Which Gelco Models This Applies To
Gelco makes flexible stainless steel chimney liners in two main alloys: 316L and AL 29-4C. The 316L liners are meant for gas and oil appliances. The AL 29-4C liners are the heavier-duty option built for oil and wood, and in Peabody’s older housing stock, we see far more of the AL 29-4C in oil-fired homes. The liner diameter is stamped on the liner’s end cap or printed on the label attached to the coil, and it will always be a round number: 4″, 5″, 5.5″, 6″, 7″, 8″. If the label is long gone, we measure the inner diameter of the existing liner with a caliper on site, no guessing.
Here’s the compatibility gotcha most Peabody homeowners don’t know: Gelco’s AL 29-4C liner has a slightly different corrugation profile than the 316L, which means the two are not always interchangeable in the same existing chase. The corrugation depth changes how the liner seats against the connector at the appliance collar, and a mismatched profile can leak flue gas at the joint. When we replace a Gelco liner, we match the alloy and the corrugation profile to what came out, not just the diameter. We also stock aftermarket equivalents from DuraFlex and HeatShield that meet the same UL 1777 listing in most applications, and we’ll tell you when the aftermarket part saves you money and when it doesn’t.
Signs Your Gelco Flue Liner Replacement Is Failing
- Rust flakes or brown grit in the firebox or at the base of the chimney cleanout. That’s the liner’s stainless steel breaking down under acidic condensation, a slow corrosion that happens over years, not all at once.
- A sour, sooty smell in the house on damp days. Moisture is wicking through the flue wall and carrying creosote or oil residue into the masonry, which lets the odor into the living space.
- Visible cracking or splitting in the liner when you look down from the top or up from the cleanout. Flex liners are one continuous wall, so once a split starts at the bottom seam, it usually runs upward over the next season or two.
- Oil burner short-cycling, sooting, or failing draft tests. Backpressure through a collapsing liner makes the burner work harder than it should, and the soot you see on the unit is often the first clue.
- Water staining on the ceiling near the chimney chase. A breached liner lets flue moisture condense into the masonry, and in a Peabody winter that moisture freezes and thaws against the framing all season long.
Replacement Cost & What’s Included
A Gelco flue liner replacement in Peabody typically falls in the $1,850 to $3,400 range installed. The spread comes from three things: the liner diameter (a 4″ oil liner costs less than an 8″ wood liner), the chimney height (a two-story colonial in the West End runs more liner footage than a ranch in South Peabody), and whether the old liner can be pulled without tearing up the chase. Some liners come out clean in twenty minutes. Others have rusted into the clay tile and need to be sectioned out piece by piece.
What’s included in the price: the liner, the top plate and rain cap if needed, the connector at the appliance, removal and disposal of the old liner, and a camera inspection before and after so you see the condition with your own eyes. That’s not an add-on. The camera footage and a plain-English verdict comes with every job, no exceptions. The price you get before we start is the price on the invoice. We also stand behind the work with our 90-Day Done Right Promise. If the liner isn’t seated right or the draft doesn’t come up to spec within 90 days, one call brings the crew back at no charge.
| Liner Type | Typical Installed Range (Peabody) |
|---|---|
| 4″ 316L (gas) | $1,850 - $2,400 |
| 5.5″ AL 29-4C (oil) | $2,200 - $2,900 |
| 6″ AL 29-4C (wood) | $2,600 - $3,400 |
| Chase rebuild or major masonry work | Quote after camera inspection |
DIY or Call Us?
There are things you can check safely. Shine a flashlight up from the cleanout and look for obvious splits or rust blooms. Run your furnace or boiler for ten minutes, then hold a smoke pencil near the draft hood to see if the smoke pulls in or spills out. If it spills, your draft is weak and the liner is likely involved. What you should not do is drop a replacement liner in yourself. The liner has to be hoisted to the top of the chimney, fed down through the flue, and secured at the top plate under tension so it doesn’t sag and separate at the seams. Get the tension wrong and you’ve got a liner that pulls apart under its own weight inside the first heating season. It also means working on a roof, sometimes a steep one, and in Peabody that roof is wet or icy for a good chunk of the year. This is not a ladder-and-a-flashlight job.
If you’re seeing any of the signs above, call us at (978) 637-8560 and we’ll put a camera in the flue and show you exactly what’s going on. The estimate is free. If the liner turns out to be fine, we’ll say so and leave you with a clean chimney and no work order.
FAQs
In Peabody’s climate, with the freeze-thaw cycles and the moisture the North Shore throws at a chimney, a 316L Gelco liner typically lasts 15 to 20 years, and an AL 29-4C lasts closer to 25 years. Oil flue gas is more acidic than gas flue gas, so oil-fired homes on the North Shore tend to eat through liners faster than gas homes. The single best thing you can do is have the liner camera-inspected every three to four years, not just swept. Call (978) 637-8560 if you don’t know when your liner was last looked at.
Small pinholes near the bottom can sometimes be patched with a stainless repair sleeve, but honestly, if the liner has pinholes, the metal is already thinning across the rest of the flue and a patch just buys you a season or two. A split seam or a collapsed section can’t be repaired safely. We’ll show you the camera footage and tell you straight if a patch is realistic or if the liner has reached the end. Call (978) 637-8560 and we’ll get eyes on it.
Most Gelco liner swaps in Peabody are done in a single day, usually four to six hours, including the camera inspection before and after. If the old liner has to be sectioned out or the chase needs repair, it can stretch into a second day. We’ll give you a straight answer on timing at the estimate. Call (978) 637-8560 to schedule.
Yes, in the most common Peabody sizes: 4″ and 5.5″ for oil, 6″ for wood, and 4″ for gas. If your chimney needs a less common size or a specific alloy, we can have it from our supplier within a couple of days. And we always carry quality aftermarket equivalents from DuraFlex and HeatShield when those fit the job just as well. Call (978) 637-8560 and we’ll confirm we have your size before we roll the truck.
If your Gelco liner is showing its age, don’t wait for the first cold snap to make the decision for you. Call Top Hat Chimney at (978) 637-8560 for a free estimate. Wendell will put a camera in the flue, show you what we’re seeing, and give you a price in writing before any work begins. If the liner still has life in it, he’ll tell you that too.
Written by Wendell Pike, Owner, Top Hat Chimney at Top Hat Chimney, serving Peabody and nearby areas.





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