WSM 18.5 PID settings

[Dave Gagnon]

I have a few cooks under my belt with my v4.0 heatermeter standalone. I love the capabilities of this little box but coming from an Auber temp control system I am noticing the Auber did a much better job of holding a temp tighter. Most of my early cooks were in the winter so I chalked it up to cold outside temps causing +- 30 degree temp fluctuations. Looking at the graphs over the entire cook it looks like a sine wave. over under but rarely right on temp... I fire up the WSM using the minion method. As far as the heatermeter it utilizes the auber blower motor system with built in air damper (20 cfm blower).

Does someone have baseline PID value's that can share that works well for an otherwise stock WSM 18.5" cooker?

 

[John Bostwick]

That's a huge blower for a WSM. What you are seeing probably is a cooling effect of the blower. The HM calls for the blower to turn on when it starts to go below the set point and then there is so much air going into the smoker, it cools the probe down the 30 degrees you see. Then since the charcoal just got a blast of air, it now has to much heat and you get the 30 above set temp.

I have a UDS and use a 28CFM. But, I never run it at max, unless its heating to temps over 300. Usually I never get over 30%. That now has dropped to 10% with a rotor damper. Soon as I turn the blower on past 40%, the temp drops like a rock and the rebound is about 50 above set point.

As for the PID setting at the moment im running with the stock settings, before it was stable(tonight), I was all over the place setting the PID values. I think they are the best values I have found.

http://uds.servebeer.com
PID standard settings
blower 10%-30%