Vertical Smoker Build

[Cruise]

I just finished a pretty large direct vertical smoker build -- my first. 84" tall X 32" deep X 21" wide. Plate steel with 7 racks made of scrap stainless expanded metal type material. 6" variable air inlet and 6" smokestack with damper at top of unit. I used two oven gas valves and burners below which work fine and safely but seem a tad undersized (about 32K btu/hr total). Wood pan sits above the burners, within 5 inches and seems to do ok at generating smoke. Door below to access burners and wood and larger door above to access water pans and meat racks. Making bbq for events. Questions I have for the experts: my first fire went ok, but not very consistent heat distribution -- up to 50 degrees difference top to bottom with smokestack pretty much closed down. Is this normal? Any suggestions on how to improve heat distribution to be more consistent? Also, any ideas on how to capture grease dripping down without inhibiting smoke and heat dissipation through the unit?

 

[kmmamm]

Try it again it with the exhaust full open. Yes, it may seem counterintuitive, but to achieve a healthy balance, the system needs to move air. This is particularly important during a cook to help expel excess moisture and prevent creosote build up. 32K of burner is probably something you are going to have to look at. It takes a lot of horsepower to:
a) get that much steel heated up and stabilized ready to cook
b) get temps to rebound after loading and opening the doors
c) overcome cold ambients
Those small burners may take an hour or more to get something with that kind of mass stabilized.

 

[Cruise]

Thank Kmmamm. I will open 'er up next firing. Attached are some photos of the unit. Any ideas on how to best capture the grease dripping down the unit without impeding the heat and smoke?

 

[kmmamm]

Looking for those photos....?

 

[Cruise]

Looking for those photos....?

Having some downloading issues

 

[Cruise]

Here's the photos

 

[kmmamm]

Didn’t realize you had it pinned into aN interior brick enclosure...that obviously will help temper the ambient factor. However I don’t think those little burners are going to get you there, check out Tejas’s website for some options with more horsepower. Are you burning lpg or natural gas? Also can’t tell if you are pulling fresh combustion air from outside or inside building.
So far as grease control, the only thing I can think of this far along in your build is to simply use pans.

 

[kmmamm]

Forgot to paste Tejas link:

Barbeque-Pits-Grills-&-Smokers-BBQ-Accessories-Tejas-Smokers

Buy all of your BBQ grills & accessories online. Tejas Smokers manufactures high quality barbeque grills, smoker pits and more. Buy online or contact at [email protected].

tejassmokers.com

 

[Cruise]

Using natural gas. The building it sits in is pretty much a shed, with large open doors to the outside. Combustion air is drawn from inside the shed, but pretty much same as outside. I can get the unit to 275 or so, but that is with the exhaust duct closed down. Will try today with the duct opened.

For the grease, is there any issue with having the water pan double as grease catcher? Will the grease on top the water stop proper moisture getting into the air? I was scheming a water pan which doubles as a grease catcher

 

[Cruise]

Thanks for the link. Looks interesting

 

[kmmamm]

Water pan will catch some of grease. If the unit is hot enough, most of the water will cook off. The stuff that runs down the walls and door is going to pool at the bottom of the unit. Hopefully there is a removable drip pan below the burners to catch stuff that makes it past the water pan. You will also want a lip or other device to funnel moisture and grease that will accumulate on the inside door into the pan.

 

[Cruise]

Thanks. We have a design in mind that should catch most of the grease in the water tray and a tray beneath the burners for the rest.

On the burners, I used oven parts to allow for safety and automatic temp control. Are there good alternatives if I used a burner like those shown at Tejassmoker ?

 

[kmmamm]

You will have to ask the folks at Tajas. Send them pics of what you have, they should be able to make some recommendations. Since you are on city gas, it is probably hooked to a low pressure line.