Double wall from stove up?

[Thunder31]

Can I run double wall stainless from the top of my jøtul f500 all the way through the ceiling support box and over the roof?
I moved into a new home and I can't get anymore than 3 inches of clearance from a large wood beam above the mantle without rebuilding the mantle and moving the stove further from the wall. This would be a completely straight run up through the roof. I understand I will lose some heat not using any single wall but I would prefer a loss in heat than risking putting single wall near that beam. The previous owners removed the stove and piping so I don't have a reference to how they did it.

 

[begreen]

Stovepipe and chimney pipe are not the same even though they both have double-wall options. Depending on the setup, it may be possible to roof support the double-walled chimney pipe so that it can extend past the beam, then transition to double-walled stove pipe to connect the stove. Pictures will help us see if there are other options or issues.

 

[Thunder31]

Stovepipe and chimney pipe are not the same even though they both have double-wall options. Depending on the setup, it may be possible to roof support the double-walled chimney pipe so that it can extend past the beam, then transition to double-walled stove pipe to connect the stove. Pictures will help us see if there are other options or issues.

I've included a picture in the post now

 

[begreen]

Thanks, that helps a lot. Now I can see that the chimney support is in. I see the beam now. It looks like there is a 3'(?) stub of stove pipe attached to the support. Is that double-wall stove pipe? If so, its clearance is 6" to combustibles.

If there isn't 6" clearance then one option would be to do an offset right off of the support box with two 45º elbows. That will give it an additional 6". Match the DW stovepipe to the brand of the chimney pipe for the easiest fitment. The picture is fuzzy but it looks like it might be Selkirk.

 

[Thunder31]

Thanks, that helps a lot. Now I can see that the chimney support is in. I see the beam now. It looks like there is a 3'(?) stub of stove pipe attached to the support. Is that double-wall stove pipe? If so, its clearance is 6" to combustibles.

That is actually single wall pipe. This being a farmhouse I believe the past owners just ran single wall next to the beam and hoped for the best. I will be replacing the entire chimney system except using the current hole they cut when installing.

 

[begreen]

How close is a plumb line dropped from the edge of the single-wall to the beam?

 

[Thunder31]

It would be about 5 inches if a single wall pipe went past the beam. 3 inches if it were double wall pipe with the added diameter.

 

[Thunder31]

What would the problem be with using chimney pipe inside the home instead of using stove pipe? The only difference I see is the clearance and color of the pipe. Generally black for stove pipe and stainless for chimney. I have heard this elsewhere but I don't understand why it's advised not to use that.

 

[begreen]

There are a couple of potential issues beside the looks. One is that the stove shouldn't support the pipe. The other is that stove flue collars are not direct connects to chimney pipe, some sort of adaptation is needed. Then there is the case where some stove manuals forbid it. Check first.

An offset is not a big deal if the flue system height is enough. We have one in our stovepipe. It was necessary to put one in when I changed stoves.

 

[Thunder31]

I believe this will be about 26 feet from the flue to the chimney cap, potentially more. The idea of using two off set angles is sounding good to me. Get the clearance I need easily that way.

 

[Eman85]

What if you made a steel shield for the beam?

 

[stoveliker]

Be aware that you might benefit from a damper with that flue heigh - without you may have too much draft (sucking heat up the chimney anad decreasing burn times and heat output). So design the stove pipe such that you have a place to put in a key damper a foot or so above the stove.

 

[Thunder31]

I thought about the steel heat shield on the beam as well and then just running double wall past it and letting the heat reflect off that. But I don't think that's probably recommended haha.
I was going to use adjustable pipe so that I could possibly add in a damper if necessary later on.

 

[begreen]

I thought about the steel heat shield on the beam as well and then just running double wall past it and letting the heat reflect off that. But I don't think that's probably recommended haha.
I was going to use adjustable pipe so that I could possibly add in a damper if necessary later on.

That's a good plan. The offset will add a little resistance which could make the draft just about right depending on the stove. I'd try it out without the damper for a month or two in cold weather and see what you think.

Side note: Some companies put their DW damper in the stove adapter. The problem with that approach is that the DW flue adapter section may not fit the flue collar well depending on the stove. If that is the case it's better to buy a 6" section of DW stovepipe and add the damper yourself.

 

[stoveliker]

Be careful with telescoping pipe containing a damper; it can be done, but it's easiest if the hole for the damper is in a section that is (when installed) not "doubled" (i.e. outside of the part where the two halves are on top of each other).

I agree that it's best to start without damper, but be aware that you might need one later. Best to install now so that (see above) it won't be hard to add the damper later.