8”x6” reducer on stove

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logfarmer

Feeling the Heat
Oct 25, 2015
258
Ohio
Ok I just bought a englander 24icd stove yesterday in mint condition, used maybe for 5 yrs, has the Manuel, pamphlet, and original purchase paper work/receipt. My question is it is 8” vent and I have a 8” thimble thru the wall to go into my clay chimney but I don’t think I will be able to install a 8” insulated liner in the chimney! Do you think I can reduce it to 6” on the stove and run it in a 6” insulated liner? From stove top to top of chimney is 20+ft. My clay liner is 6.75x10 I.d and I will be busting out the clay no matter what. What is o.d of 8” insulated liner, I’m not finding any info on 8” and once I bust clay out I will have about 8.75”x12”! Thanks for any help!
 
Your stove outlet is 50.265 sq. in.

Ideally you want the same sq. in. in pipe going all the way up.

Example:
A 6”x9” oval ... Area is A=(R1)x(R2)x3.1416 or A=(R1)3x(R2)4.5x3.1416, so area of a 6”x9” oval = 42.411 sq. in.
Ohio Revised Code says you can go 3x bigger than your stove outlet for an inside chimney and 2x bigger than you stove outlet for an outside chimney. It does not say you can go smaller if you are trying to be code compliant. In the example above the 6x9 is still to small...although allows for approximately an 1 3/8” clearance on one side and 1 1/2” clearance on the other side to get it stuffed down your chimney. Not much room to go bigger...for an uninsulated liner to boot. RockfornChimney had size from 4”-14” oval.

I may have missed whether or not this is an inside the home chimney or an exposed outside chimney.

Any chance of a complete tear down and rebuild of masonry you can build yourself and reline?

Trying to generate some discussion for you. I’m sure someone can help you.

If you’re not concerned about code compliance there are options that some might be reluctant to discuss here. Fair enough!

Reducing the stove outlet to me doesn’t scare me and if it were mine I’ll do what I’m going to do anyway. Reducing it will only allow it not to reach it’s maximum btu output. If you need the extra output, then reducing the outlet presents an issue.
 
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Outside exterior chimney, tearing down will most likely be out of the question, I’ve had a stove that was 8” piped to this chimney did fine, but wasn’t lined of course just clay liner. I really appreciate your great information.
 
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Outside exterior chimney, tearing down will most likely be out of the question, I’ve had a stove that was 8” piped to this chimney did fine, but wasn’t lined of course just clay liner. I really appreciate your great information.
I understand not wanting to tear it down.

One critical thought I think you should consider is: What’s the possibility of you changing stoves again?

Considering that and what you might do, then I would plan ahead for that scenario. In other words plan to match the stove outlet or go just a tad bigger. Matching is optimal for best draft as I’m sure you know. Also consider if you’ll ever burn coal again.

If you tear out the liner you should be able to fit a 6” round clay liner in place. Sandkuhl makes round tongue-n-groove clay liners. Might even get a 7” down it. Same with a SS non-insulated flex liner or rigid liner. You can then insulate with Perlite loose fill or other equivalent to insulate it.

If mine has to come out, then round clay insulated with loose fill will insulate it. If that ever needs fixing, break out the shop vac, sweep fill up and recycle if need be or buy another bag or three...it’s cheap. Couch’s market sells big bags in New Miami. I’ve seen this done and know guys that have did it with great results.

Leaving the current liner is always an option and extra insurance should you be able to stuff in a SS liner. Capping off the top will keep air from infiltrating and the air gap between liner and clay becomes the insulation...just like in windows, so you know it works.

Anyway, hopefully some others will chime in maybe even with better ideas. Options are good!
 
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Well I will most likely buy a different wood stove with a 6” vent in the future and that’s what my ? was to throw a 6” liner in it now and let the current stove vent through it for now until I buy the next stove. Now I have considered Plating the top and bottom and installing a non insulated liner in there so I wouldn’t have to bust the clay liner out, but the clay liner has got the glaze on there and I’m afraid to do that now. I hope to go back to coal eventually but I’d say my other half will prefer wood instead....
 
I have stuff here to remove the glaze. You are welcome to it. You’re pretty close to me. LOL! I got it in Richmond.
 
Well I will most likely buy a different wood stove with a 6” vent in the future and that’s what my ? was to throw a 6” liner in it now and let the current stove vent through it for now until I buy the next stove. Now I have considered Plating the top and bottom and installing a non insulated liner in there so I wouldn’t have to bust the clay liner out, but the clay liner has got the glaze on there and I’m afraid to do that now. I hope to go back to coal eventually but I’d say my other half will prefer wood instead....
Well for your current stove I would recommend a 7" insulated liner. But if you really are considering a new 6"stove soon a 6" may be better. And if you are planning on going to coal you will need either a heavy wall flex or rigid liner made from 316ti stainless. And yes you really want a properly insulated liner both for performance and code compliance.
 
I understand not wanting to tear it down.

One critical thought I think you should consider is: What’s the possibility of you changing stoves again?

Considering that and what you might do, then I would plan ahead for that scenario. In other words plan to match the stove outlet or go just a tad bigger. Matching is optimal for best draft as I’m sure you know. Also consider if you’ll ever burn coal again.

If you tear out the liner you should be able to fit a 6” round clay liner in place. Sandkuhl makes round tongue-n-groove clay liners. Might even get a 7” down it. Same with a SS non-insulated flex liner or rigid liner. You can then insulate with Perlite loose fill or other equivalent to insulate it.

If mine has to come out, then round clay insulated with loose fill will insulate it. If that ever needs fixing, break out the shop vac, sweep fill up and recycle if need be or buy another bag or three...it’s cheap. Couch’s market sells big bags in New Miami. I’ve seen this done and know guys that have did it with great results.

Leaving the current liner is always an option and extra insurance should you be able to stuff in a SS liner. Capping off the top will keep air from infiltrating and the air gap between liner and clay becomes the insulation...just like in windows, so you know it works.

Anyway, hopefully some others will chime in maybe even with better ideas. Options are good!
Loose fill is not a viable option. It settles over time and gets crushed and packed in at the bottom due to the expansion and contraction of the liner. I have seen this crack the bottom of chimneys out over time. It also offers no insulation value at that point. You really need to have a better understanding of the issues involved if you are going to give advice to others.
 
Well for your current stove I would recommend a 7" insulated liner. But if you really are considering a new 6"stove soon a 6" may be better. And if you are planning on going to coal you will need either a heavy wall flex or rigid liner made from 316ti stainless. And yes you really want a properly insulated liner both for performance and code compliance.
Ok thanks bholler, I will guess I’ll probably have this stove for 2 yrs maybe 3, then I will be going for a 6” vented stove. Would you say go with 6” liner now or go with the 7” now? Use a 8”x7” reducer and run it through the thimble with 7” pipe with a 7” liner now or just do 8”x6” reducer run 6” through the thimble to 6” liner? Chances of me going back to coal will be slim to none in the next 15+yrs
 
Ok thanks bholler, I will guess I’ll probably have this stove for 2 yrs maybe 3, then I will be going for a 6” vented stove. Would you say go with 6” liner now or go with the 7” now? Use a 8”x7” reducer and run it through the thimble with 7” pipe with a 7” liner now or just do 8”x6” reducer run 6” through the thimble to 6” liner? Chances of me going back to coal will be slim to none in the next 15+yrs
I really don't know this stove at all so I can't say if it will work on a 6" or not.
 
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