New propane build quirks

[kansasjeff]

Hello..new to the forum here...I just got done with building a 5'x3'x2' smoker. Used a 36co3-433 universal gas valve, white Rodgers transformer 120/240, thermotrol temp control (dial type from sausage manuf.), and a cast iron 100,000 btu burner from Tejas smoker. When I built it I broke a cover to allow 2" sides and 3 " top area for insulation. So it's well insulated!

Problems I am experiencing
1. Real aggressive (loud WHOOSH) when gas valve turns off at cycle. Doesn't affect anything just annoys me
2. MAIN ISSUE-- Unless I open bottom door smoker runs out of oxygen and burner doesn't burn fully and is real slow to light! I gave an 8" damper in center of bottom door and smoke stack is 4" diameter center of top and 20" long. I feel as though I don't have enough air draw. Just a small FYI too. IF top door is closed fast the flame gets pushed back to orifice. So that is another reason I feel it's too air tight!

I was thinking about putting dampers at top front but not sure sizes?? Hate to cut holes without knowing exact flow! That's why aim here to get help! Thank you.

 

[kansasjeff]

Ok so been brain storming here...... Obviously burner needs more oxygen .. If top chamber (smoke area) is filled with heat and as heat comes down it takes up the oxygen so if I add dampers in above the top of burner this will essentially fix my main issue as it's the same as propping bottom door open I think! Top of bottom door is above burner remember! Right??

 

[jarjarchef]

First things first.... I am not a build expert. I just love puzzles and this one has perked my intrest. DaveOmak is the man you need for the expert side.

Ok I know it is not a RF smoker, but I used the calculator to see how it would fit in it for draft.....
Guessing you have a 1' height for the firebox, yes I know it is all one chamber, but needed it for the calculator. Then I input the 4" vent and the 8" air source. Based on that you are good for air supply. However it says you need about 2X the height for your stack to create the proper draft. Again I know the way a vertical gas smoker runs differently then a RF stick burner. But looking at 8" allowing air in and 4" allowing air out. You might need a larger diameter air vent or a second one. When I have used a Pitmaker Vault the air intake for the wood burner is 2 ea vents that are about 2"x4" and the top vent is aprox 6"x6" single vent. I would look at the top vent if it was me.

 

[spoolinaz]

IMHO, that burner is WAY big for an insulated smoker. don't think you would need anything bigger than 20K for that size smoker. Most all gas smokers I have seen were not completely sealed. The rely on the outside air to feed the venturi , and have just the burner itself inside the smoker. That way you don't have to fuss with killing the O2 supply.