How long would DuraLiner last?

[farmwithjunk]

Any idea the life expectancy of DuraLiner double wall in a masonry chimney only burning wood? I couldn't find anything online and nothing specifically for warranty. Outer is galvalume which I believe is most metal roofs and it lasts decades easily.

Found a PDF where they have 100% to 15 years and 50% after 15 years for warranty. Apparently not as much faith after 15 years.

Problem is it would be quite difficult to inspect the exterior portion without taking apart the rain shield.

 

[begreen]

Should last a long time if properly installed in a good chimney. I think @Hogwildz has had one installed since around 2009?

 

[bholler]

Yeah it's really going to depend on the chimney if the chimney isn't cleaned well and there is any moisture that galvalume could corrode pretty quick. If it's dry it will last a long time

 

[farmwithjunk]

Yeah it's really going to depend on the chimney if the chimney isn't cleaned well and there is any moisture that galvalume could corrode pretty quick. If it's dry it will last a long time

Its mostly free floating inside the brick chimney except near the bottom. Otherwise it's dry but I'd expect all chimneys that go below ground level to have some moisture.

 

[farmwithjunk]

The answer to my question was less than 2 years. It rotted from the inside out at the top section. Where the upper stainless lip meets the expanded galvalume it was rotted most of the way around.

After thinking about how this product is made I'm not longer a fan. It uses 4 small rivets to connect sections but uses the outer galvalume skin to connect to a stainless rounded cap that appears to be riveted to the inner section. If the galvalume would rust the chimney would just drop since it's suspended from the top only.

It also only uses a clamp that goes on the outer skin. If the galvalume rusts the clamp can loosen and pipe drop. This would cause it leak at the tee.

The price for this product, especially in 8" is really high for inferior metal being used. Just the 8" tee is $537 and $349 for each pipe section and $228 for the cap kit. That's $2165.

 

[kennyp2339]

The answer to my question was less than 2 years. It rotted from the inside out at the top section. Where the upper stainless lip meets the expanded galvalume it was rotted most of the way around.

After thinking about how this product is made I'm not longer a fan. It uses 4 small rivets to connect sections but uses the outer galvalume skin to connect to a stainless rounded cap that appears to be riveted to the inner section. If the galvalume would rust the chimney would just drop since it's suspended from the top only.

It also only uses a clamp that goes on the outer skin. If the galvalume rusts the clamp can loosen and pipe drop. This would cause it leak at the tee.

The price for this product, especially in 8" is really high for inferior metal being used. Just the 8" tee is $537 and $349 for each pipe section and $228 for the cap kit. That's $2165.

Oh man that sucks, would cutting a vent hole on the chimney help with letting excess moisture out of the masonry chimney?

 

[brenndatomu]

Why not use a liner that is all stainless, there are plenty of them out of there, price can't be much more either

 

[farmwithjunk]

Why not use a liner that is all stainless, there are plenty of them out of there, price can't be much more either

Duraliner does have a huge advantage in OD. They claim 8 and 5/8" for 0/0 insulated pipe. Can't get that small of OD in flex.

Show me an all stainless heavy wall pipe under 9" and I'll get it. I'm going with oval flex I think.

 

[farmwithjunk]

Oh man that sucks, would cutting a vent hole on the chimney help with letting excess moisture out of the masonry chimney?

The top plate already has an air gap around the pipe. I suspect creosote creeped in-between the crimped top section. It rusted top down and inside out. Moisture I'd think would be all over and on the outside. Chase is dry.

 

[brenndatomu]

Duraliner does have a huge advantage in OD. They claim 8 and 5/8" for 0/0 insulated pipe. Can't get that small of OD in flex.

You could get to about the same OD if 1/4" insulation is used instead of 1/2"...does Duraliner have 1/2" insulation?

 

[farmwithjunk]

You could get to about the same OD if 1/4" insulation is used instead of 1/2"...does Duraliner have 1/2" insulation?

They claim 1/2" insulation, yes. Obviously compressed. If they used a 304 outer shell is say their product would be top tier for wood. I just see why they cheap out on galvalume for a premium priced product.

 

[CanFireman]

As with chimney, liners are not intended to withstand repeat chimney fires. With each fire, you run the risk of causing irreparable damage.

Inspection by a qualified professional would likely identify the cause. If it is a product defect, they may warrant if you can show maintenance history. If attributed to chimney fire damage, then answer will likely be no.

 

[bholler]

As with chimney, liners are not intended to withstand repeat chimney fires. With each fire, you run the risk of causing irreparable damage.

Inspection by a qualified professional would likely identify the cause. If it is a product defect, they may warrant if you can show maintenance history. If attributed to chimney fire damage, then answer will likely be no.

This is corrosion of the galvalume outer shell. It's not chimney fire damage

 

[farmwithjunk]

As with chimney, liners are not intended to withstand repeat chimney fires. With each fire, you run the risk of causing irreparable damage.

Inspection by a qualified professional would likely identify the cause. If it is a product defect, they may warrant if you can show maintenance history. If attributed to chimney fire damage, then answer will likely be no.

It's never been remotely close to having a fire.

 

[CanFireman]

Post some pics to show what it all looks like.

 

[farmwithjunk]

Post some pics to show what it all looks like.

Here ya go. You can see its in MUCH worse shape than initially appears. Halfway down the pipe its got pin holes bu the inside is completely rusted. You can tell it was never over heated as the original sticker is still in great shape. Pretty disgusted that a premium priced product did this in 2 years. Ended up costing me $2100 to replace it with a more durable product.

If they would use a stainless outer skin like most/all of the other pre-insulated products I'd maybe have gave it another try.

I'm sure not many would agree but I think this type of setup is dangerous long-term. Its fully suspended from the top by holding onto that outer galvanized layer. That could slip causing the t-snout to separate. They use the outer layer to rivet to a stainless ring. If the corrosion worked its way down the other half the pipe could just come apart in the chase. A simple design change could make sure this never happened even if the outer layer completely disappeared.

 

[farmwithjunk]

As with chimney, liners are not intended to withstand repeat chimney fires. With each fire, you run the risk of causing irreparable damage.

Inspection by a qualified professional would likely identify the cause. If it is a product defect, they may warrant if you can show maintenance history. If attributed to chimney fire damage, then answer will likely be no.

Even the TEE body has the plastic sticker on the back side readable, albeit fairly faded. This is 100% corrosion related and the last section which would See the least amount of heat even if it had a massive fire. See pics below.

 

[stoveliker]

Is there metal inside the masonry that touches the liner? (Anchors?)
Just trying to understand.

I agree it's very disappointing.

 

[farmwithjunk]

Is there metal inside the masonry that touches the liner? (Anchors?)
Just trying to understand.

I agree it's very disappointing.

Nope. Entirely a brick chase with no creosote build up. I'd think galvanic corrosion would be localized if that was the case and not from the inside out in my case. The rotted section was above the concrete cap less than a foot. The damage was mostly where the clamp held the pipe but its protected with the rain shield. Moisture alone certainly shouldn't corrode galvalume this fast. Its almost as if the inside wall wasn't even coated. If water/creosote got in from the outside then its a design failure IMO.

 

[stoveliker]

Nope. Entirely a brick chase with no creosote build up. I'd think galvanic corrosion would be localized if that was the case and not from the inside out in my case.

Given that metal is conducting, and corrosion is electrochemistry,.that doesn't necessarily need to happen at the point of contact.

The rotted section was above the concrete cap less than a foot. The damage was mostly where the clamp held the pipe but its protected with the rain shield. Moisture alone certainly shouldn't corrode galvalume this fast. Its almost as if the inside wall wasn't even coated. If water/creosote got in from the outside then its a design failure IMO.

I agree something is wrong here.

 

[farmwithjunk]

Given that metal is conducting, and corrosion is electrochemistry,.that doesn't necessarily need to happen at the point of contact.


I agree something is wrong here.

Yeah and even with a replacement section I decided against giving the product another try. Went with 24g rigid with 1/2 blanket which seems to maintain heat better than the Duraliner. I'm hoping what I installed is the last liner I ever do.

My brother installed Duravent pellet pipe with the outer layer being galvanized in 2005. It runs under the floor in the basement and it also rotted out seemingly from moisture in the air. He stopped using it for other reasons in about 2013.

Maybe newer galvanizing just isn't very good? I have another house with galvanized duct work in a damp basement of a 110 year old house and it looks like new and I'd guess its at least 60 years old.

 

[brenndatomu]

Maybe newer galvanizing just isn't very good? I have another house with galvanized duct work in a damp basement of a 110 year old house and it looks like new and I'd guess its at least 60 years old.

Newer galvanizing is generally thinner than in the past...prep may not be as good either...that said, if you are willing to pay for it, there are still companies out there that do VERY high-quality galvanizing, mainly for severe duty industrial equipment.

 

[farmwithjunk]

Newer galvanizing is generally thinner than in the past...prep may not be as good either...that said, if you are willing to pay for it, there are still companies out there that do VERY high-quality galvanizing, mainly for severe duty industrial equipment.

Maybe I should have said newer galvanizing is cheapened up. I know chroming is an issue with US regulations.

I'd have paid more if it was all stainless. Maybe its a race to the bottom on prices? Just like why .005 liners are the most popular. At this point I don't have any regrets on the Olympia Rhino Rigid (oval) I just installed. Fitment and connection seems super secure.

 

[brenndatomu]

Maybe I should have said newer galvanizing is cheapened up.

On most things, yes.
If you hand cut older ductwork metal and then new ductwork of the same gauge, the older is noticeably thicker...my neighbor, who is a retired tin knocker for a local HVAC place, told me the metal is the same, but the galvanizing was heavier back in the day.