Creosote removal before liner install

[chiraldude]

I have a 6 1/2" x 6 1/2" clay tile chimney 25' tall. I have run a brush through and it is mostly open except for a 5' section in the middle. Can't really tell if it is just creosote or also sloppy mortar joints. I was able to pull a 12" long 6" diameter section of black pipe through so I know I can get the 6" stainless liner all the way through but am concerned about the insulation. Definitely no way to pull a liner with insulation wrap so will have to use the vermiculite insulation mix. Problem is that I don't think I will be able to shake it down because of the restriction in the middle. I ran a flashlight down with some string and can see there is lots of creosote in the corners. If I could clear out the corners, I think the insulation mix will fall through. What I really would like to do is get a chisel and pound away in the corners.
Any ideas on how to make a chimney scraper that will do the trick?
Any advice for getting the insulation mix past restrictions like this?

 

[mellow]

You probably don't want to hear this but your best bet would be to have a pro bust out the terracotta and then run an insulated liner down. At the very minimum have a pro inspect that chimney before running a liner down it.

 

[Defiant]

You probably don't want to hear this but your best bet would be to have a pro bust out the terracotta and then run an insulated liner down. At the very minimum have a pro inspect that chimney before running a liner down it.

X 2

 

[chiraldude]

You probably don't want to hear this but your best bet would be to have a pro bust out the terracotta and then run an insulated liner down. At the very minimum have a pro inspect that chimney before running a liner down it.

I have read about this but most posts online say that this can weaken the main chimney structure.
Not sure I understand why you would say the most drastic option is the best. Running a stainless liner with no insulation would be better than using the chimney as is. The chimney is usable as but requires a good cleaning in the middle of the winter which is a pain.

 

[mellow]

I have read about this but most posts online say that this can weaken the main chimney structure.
Not sure I understand why you would say the most drastic option is the best.

Any chimney sweep that is worth anything will be able to let you know if this approach is viable after inspecting the chimney.

Running a stainless liner with no insulation would be better than using the chimney as is.

Maybe, but you should have the chimney inspected by a Pro before going this route.

The chimney is usable as but requires a good cleaning in the middle of the winter which is a pain.

Might not be usable and you will never know until you have someone inspect it professionally. Sounds like it has issues that need to be fixed before proceeding that if not done correctly could open you up to problems down the road. Ie, cracks in the tile that could ignite the creosote you are not able to clean out. Even with a liner it could get hot enough to ignite that creosote and if you have cracks it could get to be a structure fire. Just busting out a few problem tiles will not be a solution to this problem, even if you pour down thermix for insulation.

Have it Inspected by a Pro before proceeding.

Seriously. Spend the cash and make sure before going the DIY route.

 

[fossil]

...Not sure I understand why you would say the most drastic option is the best...

There isn't anything drastic about it. The flue tile is not where the chimney's strength & integrity come from...the masonry structure itself provides that. It's not terribly uncommon to remove the terra cotta liner in cases just like this, to facilitate installation of an insulated liner. It ain't cheap, but it ain't "drastic". The only people knowledgable enough properly assess the "health" of the chimney structure are professionals. I recommend getting one on-site and having this discussion face-to-face with somebody smart who can look at what we're talking about in person. Rick

 

[begreen]

Would another option be to get it professionally cleaned and then install a 5" liner with the insulation built-in like Duraliner? It's OD is 5 5/8". Not perfect, but with 25 ft of liner, I would expect it to draw ok.

 

[chiraldude]

That's a good thought. The stove I will connect is an old furnace assist that is inline with the gas (propane) furnace. It has a 6" output. I would agree that the draft with a 5 5/8 liner would be ok since I never run it wide open unless I am starting a fire.
Usually I need to run it with a barometric damper because there is too much draft.
I have spent more time with the flashlight on a string. All the crud is in the top 11 feet so I can actually chip away at it with a strip of oak.
Wouldn't I get a thumbs down for the reduction if I had and inspection from the insurance company?

 

[begreen]

That's a question for the insurance company, though they usually do not inspect to my knowledge. They usually rely on the local inspecting authority. Have they already approved the furnace installation?

It sounds like the primary issue to address here is the source of the creosote. How well seasoned is the wood that is being burned?

 

[chiraldude]

Ok, I hope it isn't bad etiquette to add to a thread this old but...
I finished chipping away the crud in the clay liner but was still concerned about clearance for a 6" liner so I went with a 5 1/2 inch liner. Used the corrugated type, not "smooth" wall.
Probably could have pulled a 6 inch but couldn't risk having to buy 2 liners.
This was so much easier than I expected. Took a couple of hours to put it all together. Total cost was about $580 for the liner and all extra parts.
I poured loose vermiculite around the liner for good measure.
I have now burned almost 4 cords of wood in the stove and so far so good.
I brushed the liner after the first cord and got hardly any soot. I just brushed it again and got about 1/2 gallon of soot and ash. As I pushed the brush down, I noticed that most of the soot was in the upper fourth of the liner. Later this summer I will take apart the top section and measure how much the vermiculite has settled and add more.
The last 1/2 cord I burned has been poorly seasoned and about 1/2 pine. If this had been the original clay liner, I would have expected 5 gallons of large creosote chunks requiring 45 minutes of scrubbing.
With the new liner, I make a point of burning a very hot fire at least once per week. (add cardboard if needed) I know its hot because I measure the temperature with a thermocouple and sometimes peaks out at 650 degrees C.

 

[begreen]

Good to hear that things are improving. If you don't already have next seasons wood stacked now would be a good time to get on it.