Looking for some Help: Offset Fie Management Problem

[kevin james]

Do you have any pics of your firebox?

Sure, here are some pictures of the firebox, the fire basket in the firebox, and the whole smoker. These were taken the day I took delivery of the pit a year and a half ago, so not recent.







Also, here is a picture of where the smoke enters the stack. As you see the entrance to the stack has what I can only describe as a cover which decreases the area at the stack entrance. This is how the pit was designed and I am really beginning to believe this is part of, if not the entire problem. Or at least the reason the pit struggles to get above 325. The builder has told me the cooker is "designed to cook with convective heat and not excessive air flow", which I honestly don't understand, but then I am not a pit builder or fabricator in any way so what do I know. He has also told me I am the only customer who has ever reported any problems with the pit.

 

[SmokinEdge]

Sure, here are some pictures of the firebox, the fire basket in the firebox, and the whole smoker. These were taken the day I took delivery of the pit a year and a half ago, so not recent.

View attachment 516413

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Also, here is a picture of where the smoke enters the stack. As you see the entrance to the stack has what I can only describe as a cover which decreases the area at the stack entrance. This is how the pit was designed and I am really beginning to believe this is part of, if not the entire problem. Or at least the reason the pit struggles to get above 325. The builder has told me the cooker is "designed to cook with convective heat and not excessive air flow", which I honestly don't understand, but then I am not a pit builder or fabricator in any way so what do I know. He has also told me I am the only customer who has ever reported any problems with the pit.

View attachment 516416

Thank you for those pics. That exhaust is a problem. You need a plenum there at the exhaust, not that little dryer vent looking thing. The fire cannot intake any more that the exhaust will allow. That exhaust has to be opened up. It’s almost exactly backwards of how we would build the exhaust.

 

[SmokinEdge]

Look at how the exhaust should be made.

https://www.smokingmeatforums.com/t...eady-to-use-rev5-6-19-15.172425/#post_1264161

 

[civilsmoker]

Thank you for those pics. That exhaust is a problem. You need a plenum there at the exhaust, not that little dryer vent looking thing. The fire cannot intake any more that the exhaust will allow. That exhaust has to be opened up. It’s almost exactly backwards of how we would build the exhaust.

What SmokinE said, that is starved for exhaust. Get out the angle grinder and cut the dryer vent thing off and leave the full pipe open. Unless you open up the exhaust it will not burn right!!!!!

Next lump burns way hotter and faster than regular coals, If you want consistency go to a Royal Oak non-lump coal. After that reduce the coal bed because that is starving all the oxygen. 1 to 1.5 chimney max. It seems counter intuitive but if you have too large a coal bed for the FB you will get incomplete combustion even if it doesn't look like it. For fire management always leave the exhaust wide open an only modify the intake.

 

[Dantij]

My Lang is the same way. 325° is absolutely the highest temp i can get. I usually cook between 240° and 260°.

 

[kevin james]

So I talked to the builder. He maintains that 1. he's built and sold nearly 100 of these over the last several years and has never had another complaint, and 2. the cooker is not designed to cook with a full open stack it is designed to cook with convective heat with the stack at least half way closed etc., so the hood should make no difference.

That said, he has one more test he wants me to do, which is the next time I cook, to pull the grate and fire basket out of the firebox and build a fire directly on top of the fire bricks and see what happens.

If that doesn't help we are going to schedule some time to have him come up and visit and he wants to see first hand how I build and maintain my fire and how I run the pit. If that doesn't result in a solution to the problem he will cut the hood off the pipe opening.

I asked a few questions though that do have me wondering if by design this is just not a good chicken cooker and isn't intended to be. First I asked what temp he cooks chicken at on his own pit, and he said he doesn't cook a ton of chicken, but when he does he cooks it at 275. So I asked him if he gets crispy bite through skin at that temp and he said he doesn't really worry about bite through skin unless it's for a comp, and he uses one of his vault smokers for that. He also told me most of the people he has sold these two cook between 250 to 275... so while he didn't say it specifically, maybe it just isn't intended to get upwards of 325.

 

[civilsmoker]

KJ, since you working with the builder to find a solution and it sounds like he is willing to work with you, hopefully, you will find the answer/solution you are searching for.

The only parting words I will share are that the principles of thermodynamics are very applicable in a smoker and the tutorial that Dave posted is based on those principles and further refined based on real world builds. Smokers built using these guidelines have no problem cooking from very low temp to high temp. To that end, proof is in the pudding....I have cooked beef wellingtons (many) with golden flaky crisp pastry @ 425 in mine......

 

[kevin james]

KJ, since you working with the builder to find a solution and it sounds like he is willing to work with you, hopefully, you will find the answer/solution you are searching for.

The only parting words I will share are that the principles of thermodynamics are very applicable in a smoker and the tutorial that Dave posted is based on those principles and further refined based on real world builds. Smokers built using these guidelines have no problem cooking from very low temp to high temp. To that end, proof is in the pudding....I have cooked beef wellingtons (many) with golden flaky crisp pastry @ 425 in mine......

Thanks civilsmoker. In addition to testing by building a fire directly on the fire bricks, the other thing I want to test is what you mentioned about using regular briquets to start my fire, with just one chimney. Now that I think of it I have never tried briquets in this smoker. I used to use them in my WSM, but found they created too much ash and that I liked lump better. When I graduated to this stick burner I never even considered trying briquets for my initial coal base. Seems like I should have at least tried it.

 

[JWFokker]

I wouldn't take off the entire 'vent hood' in one go. Maybe just half of it. The builder intended to have smoke pulled down near grate level by placing the exhaust low. You could retain some of the benefit by leaving part of the 'hood' in place while still improving the exhaust draft.

 

[sacedbysapp]

Kevis I’m not complaining I’ve had same issues and still looking for answers. I was hoping you share for info on ur post.

 

[sacedbysapp]

Kevin I’ve had a 120 gallon reverse flow smoker with a big stack big opening into the stack and I still got the soot like you did on my chicken macaroni and cheese baked beans if you look at your thread on bbq brethren I posted some links with pics u can compare. I’ve talked to a few others that had this problem and they think it’s because just have a big raging hot fire there was a video posted on your thread on bbq brethren of a slow fire you might want to watch that I’m going to try his technique. As far as the flame hitting the top of the firebox I never thought about that that might’ve also been an issue I had because I had a new coal bed grate installed in my smoker that that set up higher in my firebox and that’s when my problem started.

 

[Dantij]

Kevin I’ve had a 120 gallon reverse flow smoker with a big stack big opening into the stack and I still got the soot like you did on my chicken macaroni and cheese baked beans if you look at your thread on bbq brethren I posted some links with pics u can compare. I’ve talked to a few others that had this problem and they think it’s because just have a big raging hot fire there was a video posted on your thread on bbq brethren of a slow fire you might want to watch that I’m going to try his technique. As far as the flame hitting the top of the firebox I never thought about that that might’ve also been an issue I had because I had a new coal bed grate installed in my smoker that that set up higher in my firebox and that’s when my problem started.

Any chance you can post the videos in this thread? I'm dealing with the same issues.

 

[Dantij]

Happy holidays ! Hope everybody's cooks came out as planned. I smoked 2- 13lb. turkeys Thursday and unfortunately had the same problem with soot on the skin. Prior to the cook, I cleaned under the baffle plate. There was quite a bit of build up in there. A years worth. The firebox was clean but I gave it a scrape anyway. Not much creosote there. After the cook, I removed the skin because I didn't like the way it looked. The meat was moist, tender, and flavorful thanks to the brine. I'm still confused as ever about the soot issue. I also found that my bbq beans also accumulate the same soot regardless of where I place the pan. I cook on a Lang 48. I read in a different post that spraying the firebox with oil might be the culprit. Can this be a possibility? I spray the inside of my firebox after every cook after cleaning out the ashes. I always cook my chicken on my WSM just to avoid the problem. I'm at a loss.

 

[sacedbysapp]

There no reason spray inside if firebox.

 

[The Art of Pork]

Looking at your photo of the exhaust it doesn’t look like soot to me, it looks like ash.

I can’t say why but most likely a combo of stirring up ash when adding splits and the exhaust isn’t moving thru the cc fast enough to pull out any ash in the air with it.

I agree with most that the dryer vent cover needs to go for starters. I pretty well run my intake and exhaust wide open and manage temps by the size of fire.

 

[pineywoods]

Looking at the pictures and reading the posts I have a few questions/comments
1. If possible place the smoker so the wind is not blowing directly into the firebox vents if you can't do this maybe you can place something to block the wind from the firebox vents.
2. Do you have a grate or something to get the fire off the bottom of the smoker a few inches?
Not real high but enough room under it for airflow and for the ash to fall through away from the fire. Does it allow the ash to fall through but not allow large chunks of wood to fall through?
3. What size splits are you using and how many are you putting in at a time?
My firebox is 24x24 I use splits that are 20-22" long and about as big around as a magnum beer can. I have multiple friends with a Lang 48 you want splits 14-16" long and about the size of a regular beer can around. The other smokers I can't answer but figure an inch or two shorter than the firebox door is wide and somewhere from beer can to magnum beer can around. Don't stuff the firebox full of wood you can maintain a better fire with less highs and lows with the smaller splits and adding them more often.
Start your fire with 4 or 5 maybe 6 splits and leave the door open for a bit till you get it going then close the door and use the inlet vents to control the fire (the more they are open the more air coming in the bigger/hotter the fire) let it burn long enough to get a good bed of coals then add 1 or 2 splits as needed. If your using a reverse flow don't wait till the temp starts to drop instead look at the fire itself by the time the temperature drops the fire will be to small (it takes awhile for the reverse flow plate to allow the temp to drop) The top vent should be wide open or close to it. On the Lang 48 your probably looking at 35-45 maybe 50 minutes between adding splits.
I know the firebox vents on the Lang are below the grate in the firebox what about the other smokers. My Lang 84 has firebox vents on both sides I usually close the one on the side the wind is coming from and control the air intake with the other one.
If you build a big high fire it will impact the air flow the smoker was designed to use and that can lead to ash flying around. If the air intake vents are open with high winds coming in them it can make the ashes fly.
4. As was said don't spray the inside of the firebox with oil some people spray or wipe the outside of the firebox and allow it to cook in to help prevent rust. Don't leave the firebox door open it can allow wind to come in wrong and spread ash
Try these things it might just help if not tell us and we'll try to figure out other things to try

 

[kevin james]

Looking at the pictures and reading the posts I have a few questions/comments
1. If possible place the smoker so the wind is not blowing directly into the firebox vents if you can't do this maybe you can place something to block the wind from the firebox vents.
2. Do you have a grate or something to get the fire off the bottom of the smoker a few inches?
Not real high but enough room under it for airflow and for the ash to fall through away from the fire. Does it allow the ash to fall through but not allow large chunks of wood to fall through?
3. What size splits are you using and how many are you putting in at a time?
My firebox is 24x24 I use splits that are 20-22" long and about as big around as a magnum beer can. I have multiple friends with a Lang 48 you want splits 14-16" long and about the size of a regular beer can around. The other smokers I can't answer but figure an inch or two shorter than the firebox door is wide and somewhere from beer can to magnum beer can around. Don't stuff the firebox full of wood you can maintain a better fire with less highs and lows with the smaller splits and adding them more often.
Start your fire with 4 or 5 maybe 6 splits and leave the door open for a bit till you get it going then close the door and use the inlet vents to control the fire (the more they are open the more air coming in the bigger/hotter the fire) let it burn long enough to get a good bed of coals then add 1 or 2 splits as needed. If your using a reverse flow don't wait till the temp starts to drop instead look at the fire itself by the time the temperature drops the fire will be to small (it takes awhile for the reverse flow plate to allow the temp to drop) The top vent should be wide open or close to it. On the Lang 48 your probably looking at 35-45 maybe 50 minutes between adding splits.
I know the firebox vents on the Lang are below the grate in the firebox what about the other smokers. My Lang 84 has firebox vents on both sides I usually close the one on the side the wind is coming from and control the air intake with the other one.
If you build a big high fire it will impact the air flow the smoker was designed to use and that can lead to ash flying around. If the air intake vents are open with high winds coming in them it can make the ashes fly.
4. As was said don't spray the inside of the firebox with oil some people spray or wipe the outside of the firebox and allow it to cook in to help prevent rust. Don't leave the firebox door open it can allow wind to come in wrong and spread ash
Try these things it might just help if not tell us and we'll try to figure out other things to try

1. Wind doesn't appear to be blowing directly in to the fire box. While I can't really turn the smoker, I have tried closing the door dampers all the way down and cracking the entire fire box door open to change the direction from which air enters the fire box. It made no difference.
2. There is a grate and a fire basket that are up off the floor so air flows underneath. I have also tried removing all that and building my fire directly on the floor whihc dramatically helped this problem, but caused a different problem where It was quite difficult to even get the smoker up to 250.

3. I Splits are generally 3" diameter and 16" length, white oak. I start with one lit chimney of lump charcoal, and add 3 to 4 splits to get up to temp, then I let that reduce to coals to get a decent coal bed, and add 1 split at a time from there.
4. I do not spray the inside of the fire box.

 

[The Art of Pork]

I know it stinks to have to modify something new that you paid good money for but I’m betting your airflow thru the cooking chamber is too slow with the deflector over the exhaust.

 

[kevin james]

Another somewhat related question for you guys. How do you measure the area for the throat? I ask because I am looking at another smoker, a traditional flow offset and want to make sure everything is sufficient, with no restrictions. This is not to replace my current smoker which I still want to figure out, I just really want to also have a traditional flow.... best of both worlds.

This is a 24x48, made of 3/8" steel in the cook chamber and fire box. End caps and stack are 1/4".

The dimensdions are as follows:

Cook Chamber internals are 23.25 x 47.5
Fire box is 23.25 x 23.5 (round)
Stack is 6" internal and 40" tall (builder said it may be 48, he wasn't at his shop and cant remember off hand and said it was either 40" or 48" so I'm being conservative saying its 40")
The throat is football shaped and is 6" tall by 13" wide. I have no idea how to calculate area on this part though or if that is sufficient.
The firebox is designed to crack the door for air flow, so no door damper.

This is from a well respected commercial pit builder who has been building pits for years and is in several restaurants etc., although I don't want to mention names.

 

[pineywoods]

1. Wind doesn't appear to be blowing directly in to the fire box. While I can't really turn the smoker, I have tried closing the door dampers all the way down and cracking the entire fire box door open to change the direction from which air enters the fire box. It made no difference.
2. There is a grate and a fire basket that are up off the floor so air flows underneath. I have also tried removing all that and building my fire directly on the floor whihc dramatically helped this problem, but caused a different problem where It was quite difficult to even get the smoker up to 250.

3. I Splits are generally 3" diameter and 16" length, white oak. I start with one lit chimney of lump charcoal, and add 3 to 4 splits to get up to temp, then I let that reduce to coals to get a decent coal bed, and add 1 split at a time from there.
4. I do not spray the inside of the fire box.

Progress sort of try building the fire on top of the fire box grate but without the fire basket and see what happens. I'm thinking you will get higher temps with getting the air under the fire and letting the ash fall down below the fire so it doesn't choke it down. I also don't think the ash will fly around because the fire will still be lower than what it was using the basket.
Let us know how it works