Hey everybody! I've done some research on this in the past and it does seem like the answers tend to change depending on how old the post is and what grill manufacturer I am looking at. So, I thought I'd ask here now. How much of a gap do you guys leave in your chimney? Do you make it larger or smaller depending on the cooking conditions or the weather conditions?
Chimney Gap
- Thread starter the_horak
- Start date
Mike From R.I.
Well-known member
Mines open but not as much as in the picture.
Tim W
Well-known member
Mine is open even more 2 inches or more except on windy days the a little less than that
I have mine up open about 1 1/2 to 2 turns on my 820 with no issues 
Steve In Pa
Well-known member
Pretty much the same here except if I do a burn off I open it up more. Probably don’t need to though
Redoctapus
Well-known member
As pictured, I start with a 1/4" gap when viewed horizontally as pictured. This is also stated in my GMG manual.
From this starting position, depending on weather conditions and smoke temperatures I do some adjustments.
I close off the Chinamens cap or damper as it applies until I see whisks of smoke leaking around various places on the smoke chamber. When I see smoke leaking I will adjust the cap or damper more open until almost all leaks have stopped. I like to see some small leaks of smoke around the smoke chamber, as the wind changes slightly or maybe the combustion cycle increases slightly.
I always rotate my unit so door(s) are leeward if smoker is not isolated from wind.
I plugged the holes in my 700 and added a chimney. The unit was predrilled for a chimney so I figured it should have one. It performs nicely with these mods.
Thanks for the reply! When you say "open", what do you consider to be closed? Zero-gap between the chimney and the cap, right?I have mine up open about 1 1/2 to 2 turns on my 820 with no issues
I read previously that people set it to a 1" gap so that's what I've done since I got my 850P. I do like @Redoctapus comment about closing til you see smoke leaks.
Yes sir
Redoctapus
Well-known member
The burn pot has forced air supplying O2 to burn the pellets. There has to be circulation for the process to work. In my stick burner choking down the damper excessively causes a dense smoke which is not the flavor I seek. So circulation is a necessity, I try to balance the smoke leaving the chimney is proportional to the burner fan. If my chimney is not throttled to some extent, cold air is being pulled in at every leak in and around the smoke chamber. This is derived from hours spent tending the fire and keeping my beer fresh, that whole born on date, can't have beer expiring on my watch!
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Freedbyjc
Well-known member
Your rain cap on top of the chimney stack ... to get started, spin it up all the way to the top and run it wide open for the best air flow. It’s NOT a chimney damper like on a stick burner that you need to adjust to control the heat in the barrel, the awesome PitBoss controller constantly monitors the digital temperature probe readings and its algorithms runs the auger to regulate the heat in the barrel and the combustion fan runs constantly to help maintain the fire... so you don’t have to babysit it.
PITBOSS will tell you It is just a rain cap... wide open will give you the best air flow for a quicker startup and the best temperature maintenance. You can adjust it down some to maintain your barrel temperatures in extremely low temperatures.
Running your smoker with the rain cap down can cause it to take a long time to come to temperature, overheat and cause a flameout or an ERH overheat error code.
PITBOSS will tell you It is just a rain cap... wide open will give you the best air flow for a quicker startup and the best temperature maintenance. You can adjust it down some to maintain your barrel temperatures in extremely low temperatures.
Running your smoker with the rain cap down can cause it to take a long time to come to temperature, overheat and cause a flameout or an ERH overheat error code.
From what I have heard the cap does nothing. It’s only there to keep rain out. Many people don’t use one at all on their Pit Boss. Don’t know how true that is. I never mess with mine.
Tim W
Well-known member
If it's real windy I close mine a little but don't know if it does anything though
