More to the story!

[Rob_Red]

I made a prior post where I felt pretty proud of my self for having a seemingly super clean chimney after 2.5-3 cords. Well yesterday we were burning and the smoke detector in the house started to go off and we had that chemically creosote smell in the house. So I let the fire die out and the stove cool down and this morning I popped the flue pipe off for a look and found quite a bit of build up.

I also found a concerning crack. what do you guys think of this? Just go for a standard cleaning? Or more going on?

The chimney is an exterior masonry chimney, the first picture is the inlet to the chimney from inside my house.

The other two pictures are from either end of my removed single wall glue pipe. You can see major buildup in the 90 degree bend
What should I do about this?

This is the crack (read arrow)

looking into the flue pipe from the side that plugs into the stove.

looking into the flue pipe from the side that plugs into the wall (90 degree bend)


Looking into the connector from inside my house

 

[Rob_Red]

Up the chimney from the exterior clean out door. The door is ground level.

 

[EatenByLimestone]

I think the best course of action is to clean it and line it.

 

[Rob_Red]

I think the best course of action is to clean it and line it.

Why do you feel that way? I don’t know much about chimneys.

 

[EatenByLimestone]

OK, let's start with the crack (that my screen does not pick up, but I'll take your word that its there.) You have the chimney cleaned, how easy is it going to be to clean that crack? In old houses, its not uncommon to see ceosote soaked through the chimney and coming out inside the attic. This takes time to happen, I don't mean to insinuate that it'll leak through your chimney this year, or next, but it is a condition that will require chimney work that'll get more expensive the longer it is left uncorrected.

Positives with lining the chimney are better stove performance, easier cleaning, and safety.

 

[Rob_Red]

Thanks for the response, is the better stove performance due to the fact that it’s insulated? I suppose these keeps the gasses/smoke from rapidly cooling thus creating a stronger draft?

 

[EatenByLimestone]

That's a big part of it! The greater the temperature difference, inside vs outside, the better the chimney will work.

The hot gasses will also keep the steam from condensing on the walls and then catching wood particulates (creosote).

Let's look at area. The area of a 6" circle is 28.27" squared. The area of your 8x8 block, say inside diameter is 7x7 is 49 sq inches. Once the gasses hit this larger area their velocity slows down, and they cool off, allowing them to condense.

And then you have the coriolis force...

 

[MongoMongoson]

The crack is difficult to see in the picture. Are you showing us a crack in a terra cotta thimble or something? Or is that a length of manufactured chimney running through the wall to your vertical chimney? Taking pictures before cleaning is a good practice. Maybe after you clean that up a bit you can take some more and the crack will be more evident.

Your first pics in your previous thread looked super clean because you were taking shots from below the point where the gasses enter the chimney. Now that you have some shots up the chimney from further up, you can see the shiny black creosote on the tile. It is good that you are looking at this now rather than just cleaning your stove pipe and letting the shiny black stuff continue to accumulate.

It is normal to have the largest amount of accumulation at the bends of the stove pipe, especially single-wall.

If you use double wall non-vented stove pipe instead of single wall, that will help reduce accumulation in the stove pipe.

Whatever you decide to do.... when you start burning again, take your pipes apart and inspect them (and the chimney) after 2 weeks, then again after a few more weeks. Or maybe you can inspect them without disassembly. Anyway, inspect early and often after making changes to your system or you really don't know what is happening. That is my theory.

 

[Rob_Red]

This is interesting stuff. Now if one wanted the ultimate chimney would it be a stainless lined masonry chimney, or a stainless class A double wall setup? Also what is the safest possible setup? Can any of these withstand a chimney fire? I travel for work frequently and want piece of mind that the wife won’t run into any major problems while I’m gone. She is pretty good with operating the stove but she’s not super mindful of how it’s performing like I am.

I want to buy once/ cry once and end up with setup I enjoy. But I also don’t want to do anything unneeded.

Right now I don’t like how my clean out door is right at ground level after seeing some setups with the access higher up it seems way easier to sweep it regularly when you don’t have to make a 90 degree bend with the cleaning rod.

what do you guys recommend?

 

[Rob_Red]

Here’s a better picture of the crack. It looks like a terracotta tube that enters the chimney. The crack looks fresh since there’s is no creosote inside it (it’s still bright white). Is this part called the thimble? Also the picture is canted about 45 degrees, the crack is at the top of the tube.

 

[kennyp2339]

Insulated liner needed now unless you want to chisel and remove the cracked tile and replace it with new

 

[EatenByLimestone]

I think, what you might be seeing is light reflecting off the edge.

I've built masonry chimneys, lined them,and installed Class A chimneys. I like Class A the best! However, I admit my masonry skills are far from the best!

 

[Highbeam]

Yep, that crack plus all the cracks that may exist in your flue, are enough to condemn that chimney as non compliant and unsafe for use. You must install an insulated liner or demo the chimney and do something else.

What I did, and prefer, is getting rid of the entire masonry mess and installing a modern class A pipe system. All vertical if possible.

 

[begreen]

Good suggestions given. I am seeing glaze creosote forming on the upper section of the chimney. You don't want that. It is hard to remove. Start burning with some Cre-Away to turn the glaze into a sweepable compound. Then clean again at the end of the season.