Version 4.2.4 Heatermeter UDS


 

John Bostwick

TVWBB Wizard
This is my first long smoke with the 4.2.4 Heatermeter and so far its going pretty good and I thought I would post my set up and PID settings.

Im smoking on a UDS
3/4inch pipe inlet with a ball valve at half open(reason is that I have more control, with a smaller inlet but for higher temps its all open)
weber top with it fully open
Auber thermocouplehttp://www.auberins.com/index.php?main_page=product_info&cPath=20_3&products_id=327 a inch below center grate

Blower bfb1012HH-28cfm running at 30% max(anything higher and you get a cooling effect and overshoots when the heating of coals overcomes the cooling effect)probably could use a smaller blower, but this one has work for almost 5 years now(rain, snow, heat-very durable)
Rotodamper

1idg21.png


http://uds.servebeer.com/luci
 
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I would have to say, IMHO that is quite an odd setup as far as PID settings, the use of the roto damper as an ON/OFF valve only while you use the manual ball valve to regulate the flow instead, using a uber large blower throttled back to 30% output.... The way I would run the pit would be much different, that said, every grill is different and this is a great testament to the versatility of the Heater Meter. Different grill, different blower, different ideas... NO PROBLEM!
 
Yeah, its not your typical set up, that's for sure. But, it seems to work.

When I first made the Ver2 HM the blower was way to small for the UDS. I would have it at 100% and have to open more inlets to get the temp to respond. So, I went with a bigger blower, at the time though, there was nobody I could ask about what size to use as there was nobody else with an UDS and a HM. The ball valve is nice to have though. When I'm over 300 ball valve is wide open and when I'm below its closed down. Regardless of the temperature, the blower is usually at 30%max at temp

As for the PID settings, I think the biggest one to change is the P. the "I" I just left it where it went, when I put in .1 and it went to .10000001 lol
 
I'm thinking with the volume of the UDS a lot of your air flow may be "lost" or only semi-effective at stoking the fire. Have you seen the "air burner" I made to deliver air in my water smoker? Maybe something like that would work well for a UDS, cause it delivers the air in little jets directly to your fire, so you could use less air flow and still get the amount of heat you need....
 
I was thinking about doing that, But when I asked the question over on the Brethrens forums, people who had tried a manifold, did not notice much improvement. I still am thinking about giving it a try, as I have the pipes all ready for it, I just have to modify my charcoal basket and I think that's what is holding me up from trying it.
 
It works really awesome on my water smoker, way better than just using a wide open intake. A few other members of this forum have made their own versions and the results always seem excellent... One trick to it is to make sure you don't use too large or too many holes, if there is too much opening for air flow the "air jet" effect is minimized....
 
Just saw this and also the other UDS PID thread... I am kicking myself as I had some good settings on my 4.0 and I can't figure out where I put them.

Now on a 4.2.4 w/ Thermocouple and rotodamper, and the stock HM fan, trying to do some tuning. Anyone else on the same platform with a UDS? Just have to get a test smoke going when I can find the time to dial it in.
 
I use the rotodamper and 4.2.4 with a 3/4 inlet with a ball valve and a 28cfm blower. I use the stock PID settings and I have the ball valve at a 1/4 open on cooks below 300 and fully open above 300.
 
For the life of me, I'm going to get this damn tuning correct today...
UDS
Stock HM Fan
Rotodamper

Will let you know how I make out..
 
Very close right now... I think. UDS, stock HM blower, 4.2.4,

B = 0
P = 4
I = .005
D = 5
Fan max 75%


Testing this right now. According to the PID tuning thread, my I is out of whack. Any suggestions?


hm10.png
 
Well, me again. Had a little stint of no BBQ/heatermeter... long story.. rough times on the homefront.. anyways, back in the game.

Have a nice brisket in there right now, started out great, but, woke up to this. Getting big swings in temp.
Current settings
B = 0
P = 4
I = 0.005
D = 5

On a UDS, RO hardwood charcoal. 15CFM fan, max 100%, rotodamper.

Honestly have gone through all of the help and seem stumped in what to tweak. Any suggestions on what to move to get more stable temps would be much appreciated. I know a few folks mentioned the fan may have a cooling effect when kicking on so trying to take that into consideration as well. Thanks in advance for any advice..

hm12191.png


hm12192.png
 
Seth I can help you but I need some more info on your particular setup for your air intake and exhaust. What size and how much are they opened/closed.
 
15cfm at 100%, I would do a max of 60%-70%

What you are seeing is the temp going down and then the blower turns on at 100%, its actually giving a cooling effect and the temp drops until enough coals overcome the cooling and it then overheats, and a repeat.

When I adjust max blower %. I first get the UDS at a stable temp(any temp) and then with the Blower in Manual mode, turn the blower up to 100%, if you see the temp drop a bit, then you know 100% is to high, drop the % until you see the temp start to go up. Then with the temp stable, go to the percentage that you noted the rise and see if it goes up or down. If the temp goes up then you know the maximum % to run your blower. If it goes down then you lower the blower percent another 10% and check again.

After find the sweet spot for your blower and your setup, you will more then likely never go above that, unless you smoke at high heat above 300.
 
Rob, John, thanks for the replies, I know I'm a pain in the *** and appreciate it.

Rob, 3/4" inlet with Ball Valve, Opened the whole way. I did the bits in the one thread to figure out maximum opening size, then matched the servo opening to that and just leave the ball valve all the way open.


Thanks John, I will mess with the max blower % and get back to you guys.. hopefully have time to do that in the next few days. At least there were some (almost) stable oscillations
 
I too have a 3/4 ball valve in mine. During the summer I had to close it down some to get it nice and stable. But, during this winter, I have found a 3/4 inlet only, is not to keep it stable. During Thanksgiving I was trying to smoke a turkey at about 300+ and I could not get it above 200 without opening up the UDS for a few minutes. But soon as I closed it up it would climb above 300 and then slowly go back down below 200.

So, if I ever get around to it, I will be adding an Aux. inlet for colder weather.
 
I too have a 3/4 ball valve in mine. During the summer I had to close it down some to get it nice and stable. But, during this winter, I have found a 3/4 inlet only, is not to keep it stable. During Thanksgiving I was trying to smoke a turkey at about 300+ and I could not get it above 200 without opening up the UDS for a few minutes. But soon as I closed it up it would climb above 300 and then slowly go back down below 200.

So, if I ever get around to it, I will be adding an Aux. inlet for colder weather.

Same here on the temps, I did Turkey and had to open the second one for 300+. I rarely ever go that high, anyways, mostly low and slow for me.

I did some briskets last winter during a snowstorm and super cold weather (I'm in the Philly area). I had some cheapo reflective insulation wrap around, wrapped up the UDS... no issue maintaining 225, actually, fan barely had to work very hard.

Thanks for the help again, will report back when I can.
 
Sorry to bump old one but no need for (Yet) another thread on this. John, what's your latest config for UDS now that you've tried the different fan/damper combos?
 
John,

Out of curiosity, how do you have your 28CFM blower hooked up to your HeaterMeter? If I recall correctly, that model of blower fan is 12V 1.65A, which is a lot more than the HM can handle. Do you have it on a separate power source with an optoisolator?
 

 

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