3x8 stack size

[mapleman3]

Now that I have my 3x8 into the sugarhouse... i will be thinking of running the stack up through..... Mapleking seemed to think the stack was too big when he had it... it's 14" gimoungous if you ask me... you guys that have 3x8's are you running 12" or 14"?????

[maple maniac65]

10" on my 30x8 forced draft 26' of stack

[maple flats]

My 3 x 8 has a 12" stack, and I have 18' high, no forced draft till I finish the concrete floor as parts are now wood and I did not want to blow hot sparks onto a wood floor. I plan to have the concrete done before another season and then go with a draft fan which i already have.

[mapleman3]

I would love to have all stainless done, I know it will cost a fortune but less now than later. 12" seems right but I will still wait for more responses :)

[Sugarmaker]

Jim,
12 inch on our 3 x 10 and 20 + feet high.

Chris

[mapleman3]

Mapleking thought they gave him too big of stack.. sure seems to be the case, 12" easier to work with.

[Big maple]

Both Leader and King run 12" stacks on 3x8's and rule of thumb is twice the lengthof the arch

[jrthe3]

12 on my 3x8 started 10 feet high added 5 more feet worked great

[Fred Henderson]

12"X18' on my 3x8

[drake1271]

I had a 12'' made for me in keene N.H. with base at a very reasonable price last year. half what bascoms wanted for it! 603-209-5747 i will tell you where. josh

[Homestead Maple]

10" x 10' on an oil fired 3x8 King with Steamaway. 5.5 gal. an hour firing rate and evaporates at 140 gph.

[mapleman3]

I had a 12'' made for me in keene N.H. with base at a very reasonable price last year. half what bascoms wanted for it! 603-209-5747 i will tell you where. josh

I may call you on this, I really dont think I want to run 14"

[chenango maple]

I have an old leader 30x8 arch. I think it supposed to be fitted with 10" stack. i have been using it reduced to 6" and it seems to draw fine. Should I set it up with 10"? Wouldn`t that just make it eat a lot more wood and lose more heat up the stack?

Thanks

[tuckermtn]

I could swear that I have 14" stack on my 30 x 8 (not the one in my avitar- that was for the 2x6) my stack is pretty short- maybe 16 ft. looking to replace with stainless...Josh want to share who in Keene fab'ed that stack for ya?

[WESTVIRGINIAMAPLER]

Chenago,

What kind of gph rates are you getting with the 30x8 on a 6" stack, that may be the telltale of what you need to do??

[chenango maple]

Branden it gets a bit complicated. As I said the unit is old. Originally it had a rear drop flue pan that has since went to the boneyard. I had previously purchased a 2x4 foot ss pan before I ran across the leader evap. I did not feel that I could put out the money to replace the original pans so I made the decision to to buy a second 2x4 and modify the 30x8 to a 24x8. So I now have two 2x4 flats with dividers. Not exactly sure on the GPH but I guesstimate only about 12 GPH. When the flue pan was working it was probably more like 25+. We are building a new sap house now and thought I had better make a decision on the stack before I waste more money buying the wrong triple wall pipe. This maple hobby is a real drain on the budget. I am fortunate that my wife is still in the game or I may be sleeping in the sap house before I am done. Anyway I appreciate any advice.

Charlie

[WESTVIRGINIAMAPLER]

Charlie,

I would think you would need at least 8" pipe or even 9 or 10 inch(what mine has). 12gph seems low for flat pans. Regardless of what you do, you need to figure out a way to push the heat right up against the pans, especially behind the firebox and before the stack. If you could get the gap where it is about 1.5 inches between the firebrick and the pans before the stack exit or use insulating blanket, it should help the evap rate a lot. I got around 35 gph on my 2x8 drop flue stock and now with a high output blower and an inferno arch, I get 60 to 65 gph with a 5' flue pan.