Matt, having your UDS running at a constant 240° is a nice temp to be smoking at. I have found that depending on the area that you live in and the weather plays a lot into their performance. I am not sure how your loading your basket but If I am not using my divider I make a shallow bird nest in the middle and set my lit coals in it. When the cooker pops 200° I am closing vents to contain her at the 225°level. I hope this helps.
I have only ran it with a chimney starter full of coals as that was all I had at a time. I put them in with a few chunks of hickory and opened all the vents. I was also seasoning it so I wanted to get it hot. It got up to 350 and ran for an hourish then I closed everything down to drop the temp. It got down to 240 where it held for a while with just the little bit of coals.
I figured the Minion Method was the way to go with this. But I wondered if a 12" round by 9" tall basket full of coals would eventually burn to quick even with the vents closed.
I use the method that k.a.m. suggests. it works fairly well for me. I have 4- 3/4" air inlets of which 1 of them has a full port ball valve on it. I burn 1- 20 pound bag of kingsford "blue bag" for 14 hours or so depending on the weather. I do not burn chunks of wood in mine but instead use some wood chips or large splinters of wood mixed in. The UDS design doesnt require a lot of combustion air to burn and make a good quality thin blue smoke where wood requires much more combustion air than the UDS can handle, thus creating thick and heavy white smoke that will leave a sooty taste. I made my own charcoal recently and learned a lot about burning wood or charcoal in the process. one thing i noticed is during the beginning first hours of the burn there was a ton of moisture and "volatiles" coming out of the barrel. I believe that the wood in the UDS basket is doing the same thing since it can not completely combust.
only other thing is watch out for air leaks! they can cause a run away UDS. any leaks could cause your UDS to run hotter and become uncontrolable.
hope this helps Bud
Do you guys keep the exhaust closed down the whole time once it gets rollin? So pretty much you will have the whole thing shut down with maybe once inlet vent open or opened a little bit?
The one I cook on the most had a weber kettle (bottom half) for a lid. Its welded to the reg drum lid lip so its a pretty good seal.
The old air intake vents on the weber were rusted up stuck open so thats the way they stay. I can't adjust the exhaust, so mine runs wide open. Most of the time I have one cap off and the ball valve almost closed.
I always run my exhaust wide open all the time. I use a 2" pipe nipple that is threaded into the Bung hole on the lid. I put a cap on it when i am done using it.