# Pit Boss smoke stack



## B.Overhultz

So I just picked up a Pit Boss 700FB and I am wondering why this model does not have a smoke stack but has holes across the back instead. My grill is under a covered patio and I want to vent the smoke out. Can I just close off the holes in the back and add a smoke stack? There is already a hole in the side where a smoke stack could go just like on the other models. Did they just leave it off to make the grill more cost effective?


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## bregent

Pellet grills do not need stacks to create draft - they use a fan to force air flow. They are mostly for looks. I have a Memphis Elite that does not have a stack either.


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## rhmarw

Did you ever find a stack for your smoker?  I have the same issue, want to vent outside my cooking lean-to.  It's open on one side, but still fills up with smoke.


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## wahoowad

bregent said:


> Pellet grills do not need stacks to create draft - they use a fan to force air flow. They are mostly for looks. I have a Memphis Elite that does not have a stack either.



I am looking for education here as other related/unrelated threads regarding smokestacks have caused confusion for me. What does an internal fan have to do with draft? Or are you suggesting the fan is pulling in external air from wherever the fan is located thus creating pressure and forcing other air out of the available openings in the unit?

To further confuse it I know Camp Chef support provided me specific guidance regarding the height of my chimney cap, so they must think the unit is sensitive to level of draft.


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## RickMN

I'd like to bump this thread because I just brought home my baby Pit Boss 700D this afternoon. I was looking at the 820, but went with the 700 given that the wife and I just became empty nesters. I also noticed the holes across the back and a lack of "chimney" when I was looking at it. I'm new to the smoking world so I apologize in advance for dumb questions. Do the 4 holes across the back allow too much smoke and heat to escape from the unit?


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## Haroldm

There are multiple trains of thought on this subject in both directions.  First, let's look at the facts:  A standard smoker  chimney has about 10 square inches of outlet.  The PB700 smoker has 5 holes that total about 5.6 sq. in..  Therefore you're only getting a little over half the flow thru that a standard smoker stack has.  In theory that can cause multiple problems.  The problem I have with my 700fb is getting to lower temps (160 - 180) without the grill going out.  I would suggest that there's not sufficient air flow out of the grill, even with the fan.  I've replaced my stock controller with a PID controller made by Savannah Stoker, and still have the same problem, although not as often since it has an auto relight feature that turns the burn rod back on if temp falls 10% below set temp. ( the 10% is adjustable)  The 700fb does have a cover plate on the right end where you could put a stack if you desired, so my plan is to remove that cover, plug the holes in the back with tinfoil, and try a low and slow.  I'll report back my findings.


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## rhmarw

Looking forward to your report HaroldM.  I have a 700 and want to add a stack for outside the cook shack venting.  I will add that I don't have a flame out problem.


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## Haroldm

rhmarw said:


> Looking forward to your report HaroldM.  I have a 700 and want to add a stack for outside the cook shack venting.  I will add that I don't have a flame out problem.



Have spent the better part of 2 days experimenting with this.  I took off the cover plate for the chimney and plugged the holes in the top/back of the drum and it's made a tremendous difference in my grills performance.  Keep in mind I'm not using the stock controller, but a PID controller that has a number of settings that can be changed to increase performance.  Also, pellet brand has a lot to do with performance.  I've been using Traeger pellets which come to find out don't work well with weak auger motors like the Pit Boss has.  I've been getting auger bind which makes for tremendous temp swings.  I can watch auger% output with this controller and at times I can see the auger light on but temp is declining, then all of a sudden, temp jumps to 50 deg's over, so the pellets had the auger stuck, then it broke loose and way overshot the temp because the controller was trying to get the temp up, but no pellets were coming into the pot, until it finally broke loose and stopped binding.  I'm switching to Lumber Jack pellets exclusively.  Will report back more when my smoke stack arrives and I get it installed and get everything tweaked.  Other people who are in the Savannah Stoker PID controller group on facebook have done what I'm doing and they say they can hold temps +- 10 deg's at ANY temp from 150 to 450+ and usually +-5 deg's.


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## savannahsmoker

Haroldm, that is an excellent report about problems with the Pit Boss PB700.  One, exhaust vent holes too small two, weak auger motor of only 0.22 AMPS and problems with Traeger Pellets.  Looks very familiar also lol


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## Haroldm

rhmarw said:


> Looking forward to your report HaroldM.  I have a 700 and want to add a stack for outside the cook shack venting.  I will add that I don't have a flame out problem.


rhmarw, if you want some ideas / suggestions come over to the savannah stokers facebook page.  A number of people there have done what you're talking about and have pictures.


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## muskyjunky

I'm just curious , I'm cooking a pork shoulder on my PB700 right now and just want to mention my temps are holding pretty good between the dial, LED, and my TP-20 ... I have had the temp spikes as mentioned above and usually do on a long cook but they always seem to come back down to temp quickly for me . That being said , the P-5 setting always seems to give me most consistent temps


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## muskyjunky




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## muskyjunky




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## muskyjunky

Sorry for broken pic replies , my phone is smarter then me .


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## muskyjunky

I apologize , I wasn't trying to hijack the OP's original post / question . The temp thing got me thinking so I just wanted to offer what I have learned with my particular machine . I wondered about the sealed stack opening on my machine as well . I smoke completely outdoors so decided it wasn't something I needed to address with my particular situation .


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## Haroldm

muskyjunky said:


> I'm just curious , I'm cooking a pork shoulder on my PB700 right now and just want to mention my temps are holding pretty good between the dial, LED, and my TP-20 ... I have had the temp spikes as mentioned above and usually do on a long cook but they always seem to come back down to temp quickly for me . That being said , the P-5 setting always seems to give me most consistent temps


Glad to hear you were able to tame it.  I never could on mine.  At P=6 or P=7 my grill kept going out.  At P=5 and below the temp swings were many times +/- 50 deg's or more at any temp under 300.  Which is why I went with the Savannah Stoker PID controller.  Every imaginable setting can be changed to tweak your individual smoker.  My stack and pellets are on the way.  Will post again when everythings installed and configured.


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## Haroldm

OK, ordered stack from Rec Tech, mistake #1: stack hole in grill is 4 1/2" diameter, Rec Tech stack PIPE is 4 1/2", but they welded the mounting flange on the outside of the pipe with about 1/2" lip sticking out, so now the outside diameter of the stack where it mounts to the grill is 4 5/8"... thanks to the weld, so it doesn't fit.  Borrowed (then bought) a dremel tool and wore out 5 grinding disks to enlarge the hole in the grill so the stack would bolt in.  Loaded smoker with Lumber Jack pellets and off we went.  Could not hold 160 deg's.  After much deliberation with the gentleman who was helping me, who is a smoker expert compared to me, we took the "rain cap" off the smoke stack and started over.  After some fine tuning of the Savannah Stoker PID controller, I can now hold any temp over 200 deg's by +/- 8 deg's.  I can also hold 150-200 by changing one setting on the controller temporarily.  Bottom line, if you have a Pit Boss grill that doesn't have a smoke stack, but DOES have a hole for one, take the cover off and plug the holes in the back with tin foil and test it.  It might make your day.


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## nduetime

Haroldm said:


> ....Bottom line, if you have a Pit Boss grill that doesn't have a smoke stack, but DOES have a hole for one, take the cover off and plug the holes in the back with tin foil and test it.  It might make your day.
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Would you consider this advise to be helpful for those 700fb owners that do not have a savannah stokers PID controller but struggling with temperature swings?


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## mike243

I don't worry about temp swings, 20 either way and the food wont know the difference imo


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## bill1

I agree with not worrying too much about the temp swings in _time_.  But if you have a temperature range _across the area _of your grill you're not happy with, partially plugging off those back exhaust holes might help.  In general you want smaller (more resistive) exhaust holes in the path closest to your fire pot to encourage more hot gas to exit out the other, more distant, holes.  

Of course, you'll need multiple probes at the grill surface and more than a bit of patience to tune this in.  

I'm a little surprised that even the primo grill vendors just punch a bunch of equal size holes and don't make a little more effort in this area.


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## JWFokker

I don't think the stack does anything of value versus the vent holes in the chassis. It's not a stick burner or a vertical charcoal smoker. Draft isn't an issue when there's a fan to generate positive pressure. Older pellet grills did have smoke stacks. Common complaints were uneven temperatures. If anything it is better for airflow to be somewhat restricted.


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