Chimney as opposed to a "stack"

[Pete S]

Been having PLENTY of windshield time looking at all the BRILLIANT maple trees turning and was doing some inattentive driving,................designing.

What if you built a masonry chimney and piped your evaporator to it,.....Like you would you wood stove in the house.........rather then a metal pipe straight up.

Draft issues?, better draft?,.......thoughts?

Thanks!

Pete

[Bucket Head]

I'm no expert, but here's what I'm thinking.

I would'nt do a chimney. I think the elbows and/or curves in a woodstove-like set-up would slow up the draft. I also think the "roughness" of the brick or chimney block surface would slow the draft down a little bit more.

Think of your stack as a header pipe on a performance type engine. They are as straight as they can be, and they are "smoothbore". In both the engine and evaporator, you want your exhaust to get out quickly and easily.

Also, would'nt the cost of materials and labor for a chimney be considerably more than a stack?

Steve

[The Birdman]

I think cost would be the issue. If the cost is not then just go with a large size flue liners. As far as elbows cutting down draft I don't see why it should. My shop vac sucks the same if stright or bent.

[mapleack]

The right size and height of pipe yields good draft for a wood fired evaporator. You can have too big of a pipe or chimney, hurting your draft.

[red maples]

the red brick liners or Pottery man can't remember the name of the stuff(ADD kicking in) is very smooth so you won't get much drag from that. besides the after the first year of useing the chimney or stack there is going to creasote or carbon build up and lets face it that stuff never really comes off completely.

1 rule is the starighter the pipe the better the draft. Creating a hot fire is all about air flow and draft. and the hotter the fire the more you can boil off.

In a wood stove you need to have proper air flow but thats why there are dampers to restrict that flow so the wood doesn't burn to fast. that why we use aged hardwoods to lessen the amount fof build up in the chimney and they create better coals bla bla bla. and 2 90 degree elbows are fine for the woodstove.

If you go to big you can get back drafts in you chimney and cold spots, and not enough pull what ever. in the end your fire won't be as hot and your evaporator won't be efficient.

now having said all that. you can pipe it out that way. I have seen it done and it works good. but just make sure you use the proper size that is recomended for your evaporater. and make sure its long enough to make a proper draft!!! I would go aleast 2 1/2 times o the length of your evap. for the best air flow

[jason grossman]

I have a chimney on my evaporator(3x12). the chimney is solid mortar and brick, 5' by 6' at the base and 3' by 3' at the top, with a 16" by 16" flue liner. it is 32' high. it runs like a frieght train!! there is no problem with draft at all. if cost isn't an issue i would do it every time.