Please help, questions about a custom masonry pass through

[Rocky]

I am preparing to install a free standing wood burning stove directly in front of my existing fireplace, and I could use some input. The stove I chose has a 6" rear flue exit which is taller than my fireplace opening. My fireplace opening is 24" high, the stove's rear flue collar stands 30" high. My intention is to breach a hole in the face of the fireplace just above the opening and install a 6" masonry(terra cotta) crock for my pass through. I also intend to run a stainless flexible liner through the smoke chamber and up the entire length of my masonry chimney. I have inspected the chimney, there is an 8x13" terra cotta flue liner in good condition in place with no obstructions. I've measured the inside dimensions of the liner, and I have 7x11.5" to work with. The smoke chamber area is a little tight with strictly 6" between top and bottom, however, I can quite easily remove a few bricks to widen the area. I've included a couple photos and sketches of my ideas and options. One of the more important issues I am facing now is trying to determine all the components I need for my chimney system. I've been on the phone with sales reps and tech support for different manufacturers, but I am still having a hard time visualizing it completed.

#1: How can I transition from the stove's rear flue exit to chimney liner?
Can I just run black or stainless stove pipe all the way through the masonry crock to the flex liner
connector?
Dura vent tells me the best way is to use their masonry thimble with slip connector. If I use that product,
would that eliminate the need for a terra cotta crock, or would their masonry thimble slide inside the terra
cotta crock? Also, the dimensions of Dura vent's thimble is only 10" long, I have about 13" of masonry to
pass through.

#2: Will I have any problems fitting a 6", 2 ply, smooth wall flexible liner with 1/2" insulation blanket through my
masonry chimney flue?
One manufacturer tells me yes, the total diameter will exceed 7" and suggested I use a 5.5" liner, another
manufacturer tell me no, the total diameter will only be 6 3/4".


Any feedback will be greatly appreciated.

 

[begreen]

Hopefully that is not your fireplace. It does not look too strong. There is a third option which it to pipe it like the second (right) diagram,but tap in above the smoke shelf and damper (and above the mantel). If that is not an option then I would lean toward the 2nd or right diagram, but would use a stainless pipe from the liner and no clay tile.

 

[Rocky]

Thanks for your reply begreen. Unfortunately yes, that is my fireplace. Hopefully I will be able to sure it up a little bit with mortar when I rebuild. I like your suggestions, but I wont be able to pipe up above the mantle. Why do you suggest not using a clay tile? Are you saying I can just put a stainless pipe right through the brick, and mortar around it? what's the best way to clean up the look on the face of the fireplace?

 

[begreen]

The reason I suggested using stainless all the way is because it would provide a seamless continuous path for the smoke. I was thinking of a tee where you show the 90 and putting a cap on the bottom. Then put on an extended tee snout that would connected with the stove. Was the idea to use the clay pipe as a pass-thru with the liner going through the middle? If so, how well insulated would the liner be? It is not designed to be going through brick horizontally. Especially not if making contact with no air space.

I'm not a mason and am unsure what to do with the current setup so that structural integrity is restored. If it were me I'd be calling a pro.

 

[Rocky]

I definitely want to have a continuous path for the exhaust. I was indeed thinking about the clay pipe as a pass-thru with either the liner or the stove pipe going through the middle. I have seen other applications where people have used the stove pipe to go into the masonry crock, but not come out the back. This was typically in installations where the crock was installed right up to a terra cotta chimney liner and a SS chimney liner was not used. I made up another rendering, with more detail about my idea.

 

[begreen]

This install is off the books. If you are positive there is nothing but brick in any direction for at least 12" then it may be ok. Not sure about the lintel support. Will this be inspected for insurance purposes?

 

[Rocky]

Haha, I know! Thanks for all your input. I will be pulling a permit with my local construction official, but I don't plan on contacting my insurance company

 

[weatherguy]

Didn't someone on the board do something similar to this but just bricked up the whole fireplace opening?

 

[Rocky]

If you can find that thread, please let me know. I would like to read all about it. I'm certainly willing to brick up the whole opening, but I'm still not sure the best way to execute the pass-thru.

 

[begreen]

Todd bricked up his fireplace for his Keystone and did a very nice job. But that fireplace has a higher lintel. https://www.hearth.com/talk/threads/masonry-heater-option.64278/#post-802933

I'm wondering about cleaning the stove and flue. What stove is this for?

Also, how tall and deep is the hearth on this fireplace?

 

[Rocky]

Stove is the jotul rangeley, f 50 tl. It has a top load feature with a rotating baffle and the flue is fairly accessible from inside. Hearth is porcelin tile over dura rock which is laid on top of hardwood floor. The hearth is maybe 1/2" higher than hardwood, it spans wall to wall, and 50" out from fireplace opening.

 

[begreen]

OK, if it was a raised hearth I was going to explore lowering it with you. Good stove. Sounds like the cleaning should be doable.