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 Chimney Cleaning in Commack, NY | Top Hat Chimney
We provide independent Chimney Cleaning & Sweep - Commack and repair across Commack, and the one thing that separates our Gelco work here from anywhere else is simple: Commack’s post-war housing stock was built for oil, and most of it has since been converted to gas. Those original Gelco clay tile liners, sized for high-BTU oil burners, now vent cooler gas exhaust they were never designed to handle. If you own a Gelco-equipped chimney in Commack, call Top Hat Chimney at (631) 502-3612 and we’ll tell you straight whether it needs work or can wait another season.
We are not a Gelco dealer and we are not manufacturer-authorized. We are a local, independent service company that has worked on hundreds of Gelco systems in Commack’s ranches, capes, and split-levels. That independence matters because we have zero incentive to sell you a new liner you don’t need. Wendell Pike, our owner, has run crews through Suffolk County for over two decades, including plenty of jobs in the Burr Farms neighborhood of Commack. He learned the trade at Southwestern College in Chula Vista and picked up his first brush before he was twenty-five. These days he is known for giving people a straight answer.
Why Commack Residents Choose Us for Gelco Service
Most companies that claim to service Gelco chimneys in Commack have never actually looked inside one. We have. The technicians who show up at your door have spent years pulling brushes through Gelco clay tile liners in Commack’s 1950s colonials and 1960s capes, which means we know exactly where these liners crack, why the mortar joints spall, and what a corroded Gelco cap looks like before it lets a squirrel into your flue. That familiarity is the difference between a quick cleaning and a missed problem that costs you thousands later.
We keep genuine Gelco replacement parts on hand for the most common Commack jobs: caps with screens, standard clay tile sections, and multi-flue cap components. When a Gelco liner size has been discontinued, we use code-compliant clay tile alternatives that match Gelco’s dimensions instead of jerry-rigging something that doesn’t fit. Wendell and his crew live locally, answer the phone live around the clock, and quote a price before a single tool comes off the truck. The number you hear on the phone is the number on the invoice. If it does not need doing, he will be the first one to tell you.
Common Gelco Chimney Cleaning Problems We Solve in Commack
- Cracked and offset Gelco clay tile liners from oil-to-gas conversion. When Commack homeowners switched from oil to natural gas, the flue temperatures dropped. Cooler exhaust produces acidic condensation that sits on the clay tiles, and the repeated heating and cooling cycles crack them at the mortar joints. We find offsets where tile sections have shifted entirely, which lets exhaust leak into the chimney chase instead of venting outside.
- Spalling and deteriorated mortar joints between Gelco tiles. Commack’s freeze-thaw cycles are rough on masonry. Wet Atlantic air, repeated crossings of the freezing point, and fifty-year-old mortar combine to erode the joints between Gelco tiles. Loose mortar falls to the smoke shelf and blocks the flue. We see this on nearly every spring inspection in Commack.
- Gelco caps with corroded screens or missing lids. Rain, snow, and salt air eat through chimney cap screens over time, and once the screen fails, birds, squirrels, and raccoons get in. A missing Gelco cap lid lets water pour directly down the flue, which accelerates the spalling problem above. Cap replacement is one of the most common repairs we book in Commack during fall.
- Shared-flue configurations serving both fireplace and furnace. Original Commack builders sometimes ran the oil-burner flue and the wood-burning fireplace flue through the same Gelco clay tile liner. That configuration violates current code and creates backdrafting problems that push carbon monoxide back into the house. We find it most often in homes that haven’t had a professional cleaning since the original furnace was replaced.
- Creosote buildup from low-temperature gas venting. Gas conversions produce cooler, slower-moving exhaust, which lets creosote and soot condense on Gelco tile walls far faster than oil ever did. The buildup lines the flue and narrows the passage, which makes the backdrafting mentioned above even worse. In Commack homes with gas heat and a wood fireplace sharing a Gelco liner, this combination shows up constantly.
Gelco Service in Commack: What Local Conditions Mean for Your Equipment
Here is the one thing about Commack that most Gelco service pages will never tell you, because they weren’t written by people who actually work here. Commack’s original clay tile chimneys were sized for oil burners. When National Grid expanded natural gas service into central Suffolk County, thousands of Commack homeowners converted their furnaces to gas while leaving the original, oversized Gelco clay-tile-lined chimney in place. Those chimneys were built to vent high-BTU oil exhaust at high temperatures. Modern gas furnaces vent exhaust at far lower temperatures, which means the flue never gets hot enough to push moisture out. That moisture condenses on the Gelco tile walls, mixes with combustion byproducts, and becomes a mild acid that eats the mortar between tiles. Then Commack’s freeze-thaw winters do the rest, cracking the weakened joints open. The result is a failure pattern we do not see at the same rate in neighboring Huntington or Smithtown, where the housing stock trends older and the oil-to-gas conversion wave hit differently. Our tech serviced a Gelco-lined chimney on Cedar Road in Commack where the homeowner had converted to gas ten years prior but never relined. The Gelco clay tiles were cracked at three joints and one section was completely offset, so we performed a Level 2 inspection, documented the gaps, and installed a new stainless liner with a proper Gelco cap to restore safe venting.
Gelco Models & Products We Service in Commack
We work on the full range of Gelco products found in Commack homes, including the Gelco Standard Clay Tile Flue Liner, the Gelco 13×13 Clay Tile Liner, the Gelco Chimney Cap with Screen, and the Gelco Multi-Flue Chimney Cap. Our approach to parts is straightforward: when genuine Gelco components are available, we source them. When a liner size has been discontinued or a cap model is no longer manufactured, we use code-compliant alternatives that match Gelco’s exact dimensions rather than forcing an ill-fitting part. Most of the common Gelco cap and tile replacements are available from our local stock, which means a Commack job usually wraps up without waiting on a distributor shipment. For anything we don’t carry, we know the local suppliers who will get it to us fast.
Gelco Service Pricing in Commack
A standard Gelco chimney cleaning in Commack typically runs between $180 and $340, depending on the condition of the flue, the height of the roof, and whether we are dealing with one flue or two. A Level 2 inspection adds $100 to $250 when it is called for, which it often is on Commack’s older Gelco-lined chimneys. Mortar repointing on the exterior brick runs $400 to $900 on average, and cap replacement generally falls between $150 and $450 including the part. If the clay tiles are offset or gapped beyond an eighth of an inch, patching is not the answer. We will tell you plainly when relining is the only safe option, and we will show you the camera footage so you can see it yourself before you spend a dollar. Call (631) 502-3612 for an exact quote on your Commack chimney. Estimates are free, and we don’t play the game where the price changes at the door.
Serving Commack, NY - Our Local Coverage Area
We’re based in the Commack 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 Commack
Because the Gelco clay tiles in Commack’s 1950s-70s chimneys were sized for high-temperature oil exhaust, and natural gas exhaust burns cooler and carries more moisture. That moisture condenses inside the flue and becomes acidic, which dissolves the mortar between tiles over several heating seasons. Freeze-thaw cycles then crack the weakened joints open. It is a Commack-specific pattern tied to the oil-to-gas conversion wave, and it is the number one thing we check on every cleaning. Call (631) 502-3612 for a Level 2 inspection before your next heating season.
If the crack is hairline and the tile is still seated properly, a heat-resistant sealant can buy you time. But if the tile is offset at the joint or the gap exceeds one-eighth of an inch, patching is a stopgap, not a repair. Cracked and offset Gelco tiles let exhaust and moisture into the chimney chase, and no sealant holds up against that kind of movement over another Commack winter. We never recommend a patch when a reline is the safe, lasting fix, and we will show you the camera evidence either way.
Once a year, burn or no burn. Commack chimneys break in the off-season too, because freeze-thaw damage doesn’t care whether you lit a fire last winter. If you burn wood regularly in a fireplace that shares a Gelco flue with your furnace, you may need a mid-season check as well. Spring inspections routinely reveal frost damage that went unnoticed because the chimney was never looked at when the heating season ended. Book a cleaning now and you head into fall knowing the flue is sound.
Yes, and it comes down to the Atlantic-influenced air. Salt, moisture, and repeated freeze-thaw cycles attack the metal screens and lids on Gelco caps faster than inland areas experience. We replace more corroded Gelco caps in Commack during our fall rush than our Chimney Repair in Commack. The fix is usually same-day when we have the cap model in stock, and our crew carries the most common Gelco cap sizes on the truck. Call (631) 502-3612 and we will check your cap while we’re up there for the cleaning.
The shared flue. Original builders ran the oil-burner exhaust and the wood-burning fireplace through the same Gelco clay tile liner, which violates current code and creates serious draft and backdrafting problems. It shows up most often in Commack colonials that haven’t had a professional cleaning since the original furnace was replaced. Discovering it usually turns a routine sweep into a code-compliance conversation, and our team will show you the camera footage so you understand exactly what is happening inside your chimney before we recommend anything.
Service Areas Near Commack
Beyond Commack, our Gelco crews work in Smithtown, Northport, East Northport, Setauket, and Stony Brook. Learn more about our Gelco service in Smithtown or our Gelco service in Northport. If you’re unsure whether we cover your street, check our full Commack service area page or call (631) 502-3612 and ask. We answer the phone.
Book Your Gelco Service in Commack Today
Commack’s heating season doesn’t wait, and neither does a cracked Gelco liner. Call Top Hat Chimney at (631) 502-3612 and we will get your chimney cleaned, inspected, and squared away before the cold really sets in. We schedule ahead, quote upfront, and show up when we say we will. If it does not need doing, we will tell you that too. Explore our full Gelco sales & service page to see everything we handle.
Written by Wendell Pike, Owner at Top Hat Chimney, serving Commack since 1999.





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