Adding to Smokestack

[bison1973]

HI, I have 2 extra lengths of stack 3' each. These are left over from my hoods (I don't need them to clear the roof). They are the same diameter as my smokestack. Should I add them to it and make the smokestack 6' longer? Would it benefit me at all (draw)?

[Thompson's Tree Farm]

Bison,
It should increase the draw. Make sure you need it first. You might actually increase the stack temp without increasing the temp under the pans.

[bison1973]

How would I check to see if I need the extra length?

[brookledge]

How is the boil in the flue pan? If it boils hard all the way through then I'd say you have enough draft. The other thing you can do is measure the stack temp in the base stack about 1-2 feet above the arch.
remember once the heat goes past your pans it is gone. You can have real high stack temps and get high boiling rates but it will also use more fuel.
Keith

[brookledge]

I forgot to say that wood fired arches will probably give you the best efficiency around 800-1000. But that won't be the highest evaporation rate. Crank it up to 1400-1500 and it will boil more but use more wood
It's your choice just like how you drive your car
Keith

[bison1973]

What I have is a 3x10 raised flue no forced draft no preheater. If we were doing everythhing exactly right we could get 100 gph out of it (75-80 normaally). And even then I would say in the very end of the flue pan it never boiled real hard. So adding to the stack may be worth a try?

[3rdgen.maple]

Add the stack if it makes no difference or maes it better then leave it up. If it boils worse take it down.