Flex King Pro

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Berner

Feeling the Heat
Feb 1, 2012
388
Eastern, MA
Has anyone had any issues with their Flex King Pro liner coming apart? I cleaned my liner for the third time and looking up from the stove connection I could see a piece of the liner pulling apart creating a 3 inch wide flap. This would probably be a place for creosote to collect correct?

Should I be worried about the flap? Is their anyway to fix it?
 
Yeah, not good. I hear this is an issue on the two ply liners. I didn't find out about this 'til after I installed mine.
Normally it is the individual bands that pop up, sounds like you have a whole "section" loose?
Sorry, I don't know what, if anything that can be done about it, other than replacement. Maybe they will honor the lifetime warranty.
Chimney liner depot has a rep on here, maybe he will chime in, have suggestions. Chimneylinerjames?
I wonder if this isn't one reason why they have recently come out with the .010" thick HD single ply liner.
All the more reason to be real careful when cleaning mine! I installed a single ply liner in my second chimney this year, decided it wasn't worth the extra $ for the 2 ply
I guess it turns out, once in while, (rarely) going "HD" is not a good idea...?
 
I have bad mouthed those "smooth wall" liners for years since I installed one in 2005 and then pulled it back out for that very same reason. At best they need to tell ya to install them where the open side of the inside spiral is on the upside not the down side where it traps heat and crud.

I tossed the thing and used single wall liners from then on.
 
Has anyone had any issues with their Flex King Pro liner coming apart? I cleaned my liner for the third time and looking up from the stove connection I could see a piece of the liner pulling apart creating a 3 inch wide flap. This would probably be a place for creosote to collect correct?

Should I be worried about the flap? Is their anyway to fix it?

Berner:

Your liner problem doesn't sound good. No, not a good thing at all. How far up the liner did this defect occur?

I'm going into my forth year with a Flex King Pro connected to a Clydesdale insert. I swept it about four months ago and recovered very little creosote. See the attached photos showing Clyde's flue, the appliance connector, and the bottom of the Flex King Pro liner.

I cleaned the liner from the top of the roof after first dropping the stove baffle onto the bottom of the stove. I used a plastic brush. I didn't feel any hangups or weird bumps going all the way up and down the liner. With an insert you can't really look from the bottom of the stove and see into the liner, so I can't say for sure if there is an issue or not. However, there have been no changes in Clyde's performance or other changes that leads me to believe that there is a problem with the liner. But then again I don't have proof positive that there is not a problem.

Your problem prompts me to pull the rain cap, pull the top plate and run an inspection camera down the inside, and down the outside of the liner all the way to inside the stove to see what's going on. It's too cold and snowy to do this now, so I will do it later in the spring. I would sure hate to pull Clyde out of my fireplace and replace my liner - what a pain that would be.

Were I in your shoes, I would pull the liner and replace it. These problems never heal themselves, and the issue could get worse.

I would like to hear from the ChimneyLinerDepot rep who posts here occasionally and hear what light he can shed on your situation.

Good luck in resolving your liner problem.
 

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Can we see pictures?

Possibly what may have happened is the inner layer, the smooth wall may have been "grabbed" by the brush being used and when pulled up it could have bent a layer up. These liners are sensitive. It is not just the Flex King Pro, it is any liner made of the same construction, any company. If you put a decent dent on the outside of the liner during the install, it will create small imperfections on the inside. This does not make the liner unsafe at all, its not like it has a hole in the liner, it is still completely safe.

Or is the issue something completely different?
 
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I wonder if this isn't one reason why they have recently come out with the .010" thick HD single ply liner.
This is not why we have introduced our new liner. We have our Flex King HD now because it is the newest liner on the market and incredibly strong, best flexible liner out there. If anyone has ever used the "heavy flex" liner, the HD liner is the same construction just not heavy.

It is true you will not have the same issues you would have with a smooth inner wall liner. Basically every liner has some positives and negatives.
 
Yeah, not good. I hear this is an issue on the two ply liners. I didn't find out about this 'til after I installed mine.
Normally it is the individual bands that pop up, sounds like you have a whole "section" loose?
Sorry, I don't know what, if anything that can be done about it, other than replacement. Maybe they will honor the lifetime warranty.
Chimney liner depot has a rep on here, maybe he will chime in, have suggestions. Chimneylinerjames?
I wonder if this isn't one reason why they have recently come out with the .010" thick HD single ply liner.
All the more reason to be real careful when cleaning mine! I installed a single ply liner in my second chimney this year, decided it wasn't worth the extra $ for the 2 ply
I guess it turns out, once in while, (rarely) going "HD" is not a good idea...?

brenndatomu:

Can I conclude from your comments that you have not had problems with your two-ply liner? Is that correct? What type/brand is it?
 
Can we see pictures?

Possibly what may have happened is the inner layer, the smooth wall may have been "grabbed" by the brush being used and when pulled up it could have bent a layer up. These liners are sensitive. It is not just the Flex King Pro, it is any liner made of the same construction, any company. If you put a decent dent on the outside of the liner during the install, it will create small imperfections on the inside. This does not make the liner unsafe at all, its not like it has a hole in the liner, it is still completely safe.

Or is the issue something completely different?

I think that is exactly what happened. I brushed the liner from the top down and when I went down to empty the container attached to the bottom I noticed this.

[Hearth.com] Flex King Pro

This is still considered a closed system so like you said it's still safe to burn. However I'm nervous that it is going to collect creosote and ignite. After doing a little test with my creosote I'm now paranoid about burning my house down. I took the 4oz of black powdery creosote to my outdoor fire pit and lit a match to it. It ignited without the slightest hesitation and spread throughout the entire pile of creosote. I can only imagine what introducing the amount of air (draft) that is present when burning a wood stove.

What do you guys think, is this a rip out and replace?
 
My experience, and that of others, is the inner coil gets puckered when the liner is uncoiled for installation. Then the pucker just sits there waiting for a chimney brush to hang up on it and pull it farther out.
 
Oh, I see, yeah, I had a few of those "scales" pop up like that, like BB said, it happens when they coil it up, then it stays when you uncoil it. Or it could be your brush caught it, but even if it did, it was likely sticking up some from the get go.
I have the Flex King Pro too (8")
I guess that wouldn't bother me too much at this point. Is it where you can reach it? Maybe, tap it down LIGHTLY with a small ball peen hammer? It is obvious from the pics that you are burning pretty clean, so there is no stage 3 creosote to light off, lesser creosote will burn too (amazing that you got it to light so easy, I have done that and it took A TON of heat to light it off. Like throwing it on screaming red hot coals) but it is pretty hard to get it to light off. It appears to be loose from the bottom side? That's good, no liquid can pool there...
 
it happens when they coil it up, then it stays when you uncoil it

This issue does not happen with the Flex King Pro. As you can see the rest of the liner does not have any issues what so ever. Maybe other companies have this happen.

But as you mentioned it is a closed system with no safety issue. You installed it correctly, eliminating any possibility creosote would build up there. As mentioned try tapping it down with a small hammer and let us know how it turns out.
 
Isn't the Berner's liner Flex King Pro?
 
I am going to be installing an Accentra insert this spring. I was going to use a 15' Flex king Pro liner because of the double wall but I am not to shore after reading this. Should I get the new Flex King HD
or something else? Berner it sounds to me from reading your post that you want to replace it. I know buying a new liner is going to suck but you will be done with it. Having a chance of something bad happening like
in your experiment isn't worth the risk to you and your family in my opinion. Like the rep said it's probably fine but rember you can replace a pipe a lot cheaper than you can replace the house.
Good Luck.......
 
The Flex King HD is the best flexible liner we offer. It is incredibly strong, it will not have any issues what so ever of "fins" popping up, but it still has a smooth wall. This is the best liner for an aggressive install and especially recommended for an appliance that will be your main source of heat.

If you have ever used/seen a piece of flexible exhaust that they sell in short sections at some auto parts store, this is very similar. It is not quite as flexible as the other liners but way stronger and will not kink like the others. You can basically beat this liner up pretty good with no consequences.

We have a video in the works showing some of the features of this liner. Keep posted.
 
Thanks for the information. I didn't realize I was in the wood stove and fireplace section sorry. When I went to your site I didnt see the Flex King HD for pellet stoves. I guessI couldn't use the
HD anyways.
 
This issue does not happen with the Flex King Pro. As you can see the rest of the liner does not have any issues what so ever. Maybe other companies have this happen.

But as you mentioned it is a closed system with no safety issue. You installed it correctly, eliminating any possibility creosote would build up there. As mentioned try tapping it down with a small hammer and let us know how it turns out.
Uhhh, the OPs liner is a FKP. Mine is a 8" x 30' FKP, I had some fins sticking up when I got it, I called CLD, I was told that it happens when coiling, by a CLD salesdude. He also said it was no big deal, so I put it in like that, so far so good. But I still don't love the idea though...like I said earlier, the liner I put this year (2cnd chimney) was a single ply.
 
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I am not saying it can't happen, but it doesn't happen to every single liner. And as seen from the picture of the liner from the OP, that was not done by coiling it and the rest of the liner is perfectly smooth. My point is that you can not say coiling automatically makes all the fins pop up.
 
This issue does not happen with the Flex King Pro. As you can see the rest of the liner does not have any issues what so ever. Maybe other companies have this happen.

But as you mentioned it is a closed system with no safety issue. You installed it correctly, eliminating any possibility creosote would build up there. As mentioned try tapping it down with a small hammer and let us know how it turns out.

I'm a little confused. Is this not supposed to happen with the Flex King Pro?

Should I expect this to happen more and more the more I clean the liner?
 
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James nobody is saying it makes them all pop. But some is too many. All of a sudden when you uncoil it that smooth wall, ain't. It isn't any surprise or anything new. Mine did it in 2005. Everybody's inner strip smooth wall liners do it.

If it wasn't a common problem I seriously doubt the urge to develop the new HD smooth/single wall liner would have come about.
 
This is not supposed to happen. What happens many times is the liner will get a dent in it from the outside, this may happen during the handling of it during the install. That dent causes a little lift on the inside layer of the liner. Then when you brush it with an aggressive brush this may happen.
 
Would this be considered a warranty defect?
 
A defect if the liner becomes dented? This is the nature of the liner, the inner layer has the possibility of raising slightly if dented. There is no defect in it. Just as a single ply liner can kink on itself, especially when made oval. Not a defect.
 
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