Building a smoker and need to extend smokestack

[buckhunter]

Hi Y'all!,

   Currently building a reverse flow barrel type smoker for a business venture.  I plan to do functions, sell from locales, and eventually get product to supermarkets.  Here's my problem.  I live in a neighbrhood where houses are basically built on top of each other (I've gotta' get back to the country, haha) so I want to build an extension to my smokestack that can be taken off. I know, it's gonna look odd. Unfortunately the extension needs to be about 12 feet long (want to be considerate of neighbors in regard to smoke).  As long as I keep my valve low, any suggestions or problems of feasibility?  Thanks.

Smoke 'em if you got 'em

 

[sqwib]

A twelve foot stack will back up on you.

I am not 100 percent sure, so ask around someone may have a better solution.

If you are smoking correctly the smoke should be negligible so I wouldn't sweat it.

 

[buckhunter]

Thanks for the reply.  Do you think I will have reverse flow even with a butterfly valve closed the majority of the time and opened once in a while to control smoke and heat? 

 

[daveomak]

BuckHunter, morning and welcome to the forum...   Glad you stopped in....  About your smoker... In my signature line... right click on "smoker design" and "pit calculator" and open those links in a new window.... there is some very useful information to be had there...  about the exhaust stack... it should be wide open at all times when cooking... as far as smoke goes, properly seasoned wood cut into 2x2 splits should not smoke very much and should be no problem...  Get back to us, we are here to help...   Dave

 

[sqwib]

Thanks for the reply.  Do you think I will have reverse flow even with a butterfly valve closed the majority of the time and opened once in a while to control smoke and heat? 

If I understand you correctly I think you will have problems with a 12 foot stack no matter what you do.

I'm not sure if head pressure applies to smoke like it does water but 12 foot sounds a bit extreme.

Maybe if you put an exhaust fan on the end to pull the smoke, assisting in the draft may work.

I honestly don't think you should have smoke problems if you control the fire correctly, so I would ditch the extension idea

One of the most important things in a smoker is to have air circulation (draft), you want the stack to pull the heat and smoke from the fire under and over your food and exit at the exhaust.

You need to find that balance of draft with adjusting your intakes (located under the fire in the firebox) you do not want to choke it with valves that are in place after the firebox.

Hope that sounds clear?

 

[bluffton smoker]

I agree with the previous entries. Please control your smoker via the air inlets on the firebox and run the stack wide open.

A little story. I'll try to make it short...

I had a small horizontal off set smoker, not a RF. Still have it. In 1995 I had it set up under a roof (shade) that was about 9' high. On days when we had a low pressure weather system on us the smoke would leave the stack and just hang around us and not lift like when we have a high pressure weather system. I took a 8' length of metal downspout from an old gutter system. It fit over the stack perfectly. I ran this up thru the roof and fired the smoker up. This extended stack created MORE draft as the heat rose, it drew more. It ended up drafting too much and had a hard time keeping my temps down. BUT once I got my temps down, I ran into the issues SQWIB is describing. I then didn't have enough heat generated to carry up this extended stack and I ended up with stale smoke I couldn't vent off. AND on days when the barometer would swing up, the extended stack worked, as long as I could keep the temps in check. If I let them creep up on me, they would soon run away. I ran this stack for many months. I just had to watch my temps religiously. This was on a small backyard smoker with a little bitty fire box.

I guess if a tall stack addition like a downspout or such is inexpensive, TRY IT.  And please let us know how it turns out.

I'm NOT attempting to overrule anyone, just trying to encourage you to go ahead and color outside the lines a bit. The worse that can happen is it doesn't work and you are out a few bucks and everyone can rag on me for sticking my nose where it don't belong. BUT you are exhausting your options for a business venture. I applaud you for your entrepreneurial spirit AND balancing your concern for your neighbors. GOOD FOR YOU!!!!  Congratulations...

 

[daveomak]

Squib and Bluffton are correct....  Too tall a stack will cool off and cold air will not rise, it will plug the stack and you will have no air flow...  

That is of course assuming the extreme case....  a properly operating smoker will invite the neighbors over....   Dave