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View Full Version : UDS lid differences


MushCreek
11-17-2010, 07:03 PM
I run two different lids on my UDS, as do two friends of mine. We've all noticed the same thing: The tall lid, made out of 1/3 of a drum, runs much hotter than a Weber lid. With all intakes closed, mine will gradually sneak up to about 275 or so, where with the Weber lid, and one intake open, it's more inclined to stay 225-250. My friends noticed the same thing. I do know the exhaust is bigger on the tall lid; it works about to about 20% bigger. Do you think that's what the difference is? Maybe I should throttle that exhaust just a little? I know it's bad to close the exhaust too much (creosote). It seems like we're getting a decent seal with either lid. I've also noticed the problem is worse on windy days, probably because of having one big hole instead of 4 little ones. Thoughts? BTW- My thermo is 12" long (not braggin'), and about an inch under the meat.

Dave Russell
11-18-2010, 08:13 AM
I think you already know the answer to your queastion. W/ the weber lid, it's just getting less air. What else could it be, right? Maybe some thermodynamics engineer will chime in, but I don't see how it could be anything else. Do you use the Weber lid for low-n-slow, and the other for HH or chicken?

colonel00
11-18-2010, 09:11 AM
Sounds like you have some serious leaks with your 1/3 of a barrel lid. With the intakes closed, the fire should die. Even getting a little bit of air (i.e. the daisy wheel on the Weber lid open) my fire dies when I close my intakes. How do you have the exhaust setup on the 1/3 drum lid?

MushCreek
11-18-2010, 04:09 PM
I would think it would be a leaky lid, but I know of three drums all acting the same way. The exhaust on the barrel lid is the 2" pipe fitting it came with. I added a 9" tall stack to mine, which seemed to help, but it still runs hotter. This weekend, I'm gonna try throttling the exhaust a little and see what happens. If I close the exhaust, it dies quickly. I may also experiment with sealing the lid somehow. I keep wondering if a single large opening somehow behaves differently than 4 or more small ones.

I prefer the barrel lid since it looks cooler, and has more capacity. I can stack grates and get 3 levels if I want.