PID & Fan Recommendations For UDS Build

[apn73]

Hello All,

I finally burnt through my old UDS drum after 13 years of faithful service, and now I need to make some decisions before I start making holes in the replacement drum. The decision is "to PID, or not to PID," that is the question. I really think that I would like to try it, just because it seems to make the UDS just that much more "set it, and forget it." The UDS that I built was never all that set it, and forget it, and found that you still had to monitor the temperature closely, and make adjustments. Not a lot of fun on overnight smokes, that's for sure....

So , what do you folks think of your PID controlled UDS's? What has your experience been with them, and would you do it again. The biggest thing that I'm after with this post is the biggest bang for the back with a PID and fan on this style of smoker. I've read lots of posts written by people that are using the ThermoWorks Billows, a few using the Inkbird, and yet others building a DIY PID controller. I'm not too sure about about the DIY controller, could definitely see myself screwing that up royally. That being said, I guess I'm looking for an all-in-one kit, or one where the pieces are easily matched up to work together, like the Billows? What are your thoughts? Thank you for any hints or suggestions that get thrown my way.

Merry Christmas & Happy New Year,

Adam.

 

[Brokenhandle]

Can't help but I'll bump your thread so maybe someone will see it and can help.

Ryan

 

[JC in GB]

PID controls work well for drum smokers. Or, so I have heard. I haven't tried them on a drum yet myself. I make my own PID controllers and I love the performance I get from them.

Here is a good bit of information if you are interested in a DIY project.

PID Controller Tutorial and Build Information

Good day all. It was suggested that I start up a PID controller tutorial thread. Sounded like a good idea to me so, here I am. What is a PID in the first place? P - Proportional I - Integral D - Derivative These parameters describe gain formulas. Gain determines how fast and how hard your...

www.smokingmeatforums.com

JC

 

[apn73]

PID controls work well for drum smokers. Or, so I have heard. I haven't tried them on a drum yet myself. I make my own PID controllers and I love the performance I get from them.

Here is a good bit of information if you are interested in a DIY project.

PID Controller Tutorial and Build Information

Good day all. It was suggested that I start up a PID controller tutorial thread. Sounded like a good idea to me so, here I am. What is a PID in the first place? P - Proportional I - Integral D - Derivative These parameters describe gain formulas. Gain determines how fast and how hard your...

www.smokingmeatforums.com

JC

Huge amount of information, actually. Thank you!

 

[Fraser]

Built my first drum and run the Signals with Billows.

I really like not having a lot of clutter. The Signals runs the meat probe(s), pit probe and fan controller and throws it all on the graph. First few cooks I enjoyed running out to the pit every 15 minutes to see…….nothing happening! Set-forget like a pellet.
Holds temps very well, and I can change pit temp from the app, just like a pellet.

Hope this helps!

ps- I bought the pipe nipple adapter for the Billows such that I can use it “bare” or with the Billows. But since I’m usually using the Signals anyway, why not?

 

[K12]

I've recently added a pid controller to my UDS. I've installed the auberins 3615 with 20 cfm Blower.

WIFI BBQ Temp Control Kit with 20 CFM Blower, 3-Probe, 2nd Gen. [KIT-3615-20-G20] - $199.99 : Auber Instruments, Inc., Temperature control solutions for home and industry

Auber Instruments, Inc. WIFI BBQ Temp Control Kit with 20 CFM Blower, 3-Probe, 2nd Gen. [KIT-3615-20-G20] - This listing is for Weber Smokey Mountain 22". Auber’s SYL-3615 Wi-Fi BBQ controller is our newly released BBQ controller on November 2020 with two major changes: A new Wi-Fi module that...

www.auberins.com

I've experienced some issues with the setup and looking for some feedback.

- it when the fan kicks on, the cooler air from outside drops the temperature inside the drum, the controller then ramps up the fan, which compounds the problem. The pit then over shoots it's target temp by a mile, so the controller turns the fan off. By the time the drum cools, the coals have somewhat extinguished. This causes the drum to drop below the target temp by a mile and the cycle continues.

I have my basket about 2.5 inches off the bottom of drum and the air coming in about an inch from the bottom. Right at the drum wall. I have no baffle or anything above the basket. Wide open to the grates.

Any help would be appreciated

 

[JckDanls 07]

Does the fan have a slide gate on it to choke down the amount of air being blown into the smoker ?

 

[JckDanls 07]

K K12 ... Looking at the specs... It says the fan has adjustable speed... Maybe slow the speed down some so it's not drawing as much cool air ... and it's not stoking the fire as hard...

 

[Fraser]

the cooler air from outside drops the temperature inside the drum

This should not be happening; the fire should react (positively) to any increased availability of air, regardless of temp. I’d say check for air leaks but you say the fire extinguishes when fan turns off, leading me to suspect it’s not leaks (worth checking anyhow).
You didn’t mention where you placed the pit probe, I’m assuming clipped to center of grate, roughly 9” or so above basket? Might be interesting to measure temp response time of your setup.
Next, I’d look at intake velocity; is the fan creating a Bernoulli across the bottom of the basket? Can you dial the blower speed down? Worth a try, but your 20cfm blower doesn’t seem excessive (my Bilows is 40something cfm I think, but I run the baffle 1/2 closed). Or might try a baffle of some kind under the basket? I’m thinking a strip of sheet metal wrapped around the ‘back’ half of the basket extending to the floor to deflect air up into bottom of basket? You can probably come up with something more clever, but you get the idea.
Your pit temp should almost immediately rise when fan kicks on, regardless of ambient temps.
Hope this helps!

 

[K12]

Does the fan have a slide gate on it to choke down the amount of air being blown into the smoker ?

The fan doesn't, however I've attached the blower to a ball valve and have the ball valve ~2/3 closed.

K K12 ... Looking at the specs... It says the fan has adjustable speed... Maybe slow the speed down some so it's not drawing as much cool air ... and it's not stoking the fire as hard...

This should not be happening; the fire should react (positively) to any increased availability of air, regardless of temp. I’d say check for air leaks but you say the fire extinguishes when fan turns off, leading me to suspect it’s not leaks (worth checking anyhow).
You didn’t mention where you placed the pit probe, I’m assuming clipped to center of grate, roughly 9” or so above basket? Might be interesting to measure temp response time of your setup.
Next, I’d look at intake velocity; is the fan creating a Bernoulli across the bottom of the basket? Can you dial the blower speed down? Worth a try, but your 20cfm blower doesn’t seem excessive (my Bilows is 40something cfm I think, but I run the baffle 1/2 closed). Or might try a baffle of some kind under the basket? I’m thinking a strip of sheet metal wrapped around the ‘back’ half of the basket extending to the floor to deflect air up into bottom of basket? You can probably come up with something more clever, but you get the idea.
Your pit temp should almost immediately rise when fan kicks on, regardless of ambient temps.
Hope this helps!

The pit probe is in the middle of the grate, but its on the top grate and more likely 20" above the basket.
I thought the same regarding velocity of the fan. The fan does have adjustable speed. I'm running the fan in fan speed mode(controller uses fan speed to control how aggressive the response is) I did however, set max fan speed to 50%. and close the ball valve ~2/3.
I thought about a baffle directing the air into the bottom of the basket. This would stop the air in the drum from mixing and cooling slightly, which causes the controller to raise fan speed.
I haven't heard of anyone else having to do this, so I was wondering if there was something else I'm doing wrong. Is there anyone with experience with Auberins controller?

 

[Fraser]

Any way you could check the response time of your controller? Might be interesting. Maybe something like:
Set drum up for ‘un-assisted’ cook, using bottom vents as usual, fan plugged in but not installed. Once temp stabilizes to whatever your drum likes to run, set controller temp slightly lower than that. If possible, place a known good probe next to the controller probe to verify they match. Then shield the probes (wet rag) to verify the controller sees the temp drop and turns fan on, noting the time lag (why it’s better if fan not connected to pit). Then uncover the probes and note how long it takes for fan to shut off again.
It may be that the controller delta (between off-on) is defective or needs adjustment.

ps-If you’re worried about air mixing, try placing a perforated pizza pan on top of the basket.

 

[JckDanls 07]

K K12 ... I would turn the fan speed way down... only needs a whisper of air...

If all else fails... Call Auber support...

 

[K12]

I decided to change where the blower air enters the drum. I extended it from the wall of the drum and added a 90 so the air comes up directly underneath the basket. This solved my problem, the pit usually stayed within 5 degrees in either direction.

Max fan set to 35%, fan ball valve set ~30% closed.

The only issue i had was when the pit was climbing to its set temp, 225 initially and then 275 after an hour. The controller would continue with the fan well after the pit hit its set temp. I would interrupt it at 10 degrees over, by going into the config and back out. I didn't change the config, but the fan would stop immediately and the pit would settle perfectly after that.

There was a false "open lid" detected, so the fan stopped, this caused the pit to drop in temp. After the threshold, the fan started again. I left the controller alone this time and the temp rose 25 over set temp before the fan turned off and pit temp settled. This overshoot has to be a controller setting/issue.