Flue Constriction/Massachusetts

[Vic99]

The saga of trying to get a wood burning stove continues . . . . . want a tough problem to solve, please read on . . .

So before we finalized the deal on a soapstone stove, the dealer came out to check out my chimney setup.

Background: 1920 Dutch Gambrel house, 2 floors, 1550 square feet, chimney with 2 flues in the middle of the house. I want a Hearthstone Homestead stove vented out of the chimney.

When we got on the roof and looked down the fireplace chimney flue, it appeared that the chimney actually constricted and turned (two turns actually) near the fireplace area [although we did not actually measure distance down]. It appears that when the mason built the chimney, he used extra mortar to craft an ~45 degree-elbow-like-bend in the fireplace flue. Because he did this, the flue does not appear wide enough to take a 6 inch liner at that point.

Why was it built like that? The dealer seemed to think that it was done to conform to the room in which the fireplace sits. The living room is a 15 x 15 square, except where the fireplace is located. That corner is shaved off to give a kitty-corner-like effect. The dealerthinks that the turn was made to line up with the room. I assume this conforms to some kind of code or chimney stability issue.

On one of my first posts, when I was trying to size a stove to the to my house size, someone (I forget who, I'm sorry) suggested that in order to increase BTU radiation into the room, that I set up a free-standing stove in front of the fireplace and have a cast iron pipe come straight out of the top of the stove for 3-4 feet and then bend at 90 degrees and go into the chimney through the wall . . . . if this actually bypasses the twists and turns and allows a 6 inch liner to be dropped down would I be able to meet code with this kind of configuration?

If not, does anyone have a suggestion?

This seems like a deal killer for using my fireplace, unless I go natural gas . . . . not really considering that . . . there are so many things I like about the whole cut wood burning thing . . . . its a bit frustrating because I been looking into this for a month and like you guys that read this, I'm totally hooked.

Please advise.

Many thanks.

 

[webbie]

1. If the flue tiles are in good condition, maybe you don't need to reline it?
2. Maybe a 6" will fit down, or perhaps a slightly oval or square-rectangle flue liner.
3. The installation you mention with a stove in front and then venting up and through the wall should be able to work - this type of install would need a liner, but as you mention you might be above the turns.

 

[Hogwildz]

I'm not the best versed on code, but I think you'd be ok with your idea.
As far as the 45degree inside the chimney. Are you sure thats not the smoke shelf your looking down into?
Can you get an oval flex pipe down through there maybe? Did you take pics by chance?

 

[stoveguy2esw]

you should be able to do that provided that the pass through into the flue is code compliant and the liner is a s well, fireplace would be a dead animal at that point though , but who cares right? elk will likely be along to confirm me or tell me im wrong (as long as he gets you straight im kool with it. he knows more about it than i do, but im pretty sure you can have a wall thimble installed to drop a liner down to and connect. i hope im right for your sake. i'd hate to see ya be stuck with NG as the only option. personally i'd rather waste wood heat up the chimney than have to heat with gas, just aint the same heat.

 

[Hogwildz]

you should be able to do that provided that the pass through into the flue is code compliant and the liner is a s well, fireplace would be a dead animal at that point though , but who cares right? elk will likely be along to confirm me or tell me im wrong (as long as he gets you straight im kool with it. he knows more about it than i do, but im pretty sure you can have a wall thimble installed to drop a liner down to and connect. i hope im right for your sake. i'd hate to see ya be stuck with NG as the only option. personally i'd rather waste wood heat up the chimney than have to heat with gas, just aint the same heat.

And surely does NOT smell as good

 

[Vic99]

Mr. Administrator: The flue is brick and does not currently have any liner.

The guy that came out to check didn't think an oval would work . . . . too narrow. He seemed to think that a liner would get torn up down there.


Mr. Hog: I don't know if it is a smoke shelf, but the installer didn't comment that it might be. Unfortunately I did not get a picture, if I can get a ladder tall enough, I'll go back up.

Another thing I just though of: the mortar-based curve could be below the actual fireplace and in the basement . . . I know that sounds unlikely, but I didn't actually think that this would happen either . . . again, I need a ladder so I'll have to talk to the neighbor.

Yes, I hope that elk reads this too.

Thanks.

 

[elkimmeg]

Sorry I was out visiting other forum member today read the post under this. Since you have an interior chimney, you may not need to re-line your existing chimney, providiing the existing flue liners are in good condition. If your existing flue is an 8/12 or 7 /11 inside measurements a direct connect can be made. One would require a good damper block off plate and run your flue liner to 1/2 way into the existing clay flue. Is this the best draft and cleaning stenerio no. but setups like yours require compromises, but it is code compliant. You will save the cost of a full liner instalation and start feeling heat and relief from your fuel cost. Should you enconter problems with your inspector, just pm me and I will provide the code where your installation is acceptiable to him. Again you are a member for life on this form ,we will require details and pictures of your stove fired up. Your experience can help others

 

[Vic99]

Elk says:

Since you have an interior chimney, you may not need to re-line your existing chimney, providiing the existing flue liners are in good condition. If your existing flue is an 8/12 or 7 /11 inside measurements a direct connect can be made.

Perhaps I am not understanding the terminology . . . . when I look down my chimney from the roof, I see brick and mortar nearly all the way down. I see no metal or ceramic, or clay liner.

Deep down in the chimney, near the fireplace, there is an area where a mortar or clay-like substance is built up inside the chimney. This build up narrows the fireplace opening at that point to 3-4 inches. It also seems to purposely serve as a bend in the flue. Likewise this build up seems to extend for only a few feet . . . it is tough for me to tell whether it is ~3 feet long or 6 feet long because when looking down from the roof it was too far away.

Next to this is a separate flue that takes both my natural gas water heater and nat. gas furnace. This flue seems to be an unobstructed straight shot all the way down.

Elk, are you saying that I will be code compliant and safe without a liner? I plan to burn 24/7 with a soapstone stove.

Next chance I get to borrow a ladder and go on the roof, I will provide photos, but it probably won't happen for a few days.

Thanks again.


And, if not , does it make sense to do the iron pipe-elbow trick mentioned above. Thanks.

 

[elkimmeg]

Note I said you had to have an existing clay liner in good condition. No appliance /stove should be vented into a non lined chimney.
especially and older one in an interior location.

From your description, I do not know of a way, it can be stainless steel lined.

 

[seaken]

Well, first of all, the dealer should have taken a tape measure with him. But it sounds like you need a chimney professional. It is probably beyond your dealers ability. I would call in some chimney professionals and get their opinions. It may be possible to go with a specially sized liner or a liquid liner solution. I suppose it will depend on your budget but it is probably possible. If the cost becomes too high you may consider putting in class A type HT metal chimney instead.

Start with www.csia.org

Good luck,
Sean

 

[Vic99]

I found this picture at http://www.css.cornell.edu/de21/newhouse/images/new-woodstove.jpg.


What about a set up like this to bypass the constricted part of the chimney? Would there be a way to get this elbow pipie set up code MA code complient?

The idea would be to use a steel liner down the chimney to meet the iron pipe. The iron pipe (or whatever pipe material is used) would go into the existing brick of the chimney and in theory connect to the steel liner.

 

[seaken]

Yes, it is possible. However, there are issues that must be addressed by a chimney professional, such as ceiling clearance, wall pass-through, masonry construction, liner and cleanout installation, etc. We can't tell from here what will work. Give the CSIA a call.

Sean