Well once again Auber customer service comes through, shot off an email last night and got the answer this morning
The auto-tune needs to heat up the controller to the set point, wait the smoker to cool down . Then, heat up again. It needs to do this three times. The longer for the system to cool, the longer it will take for the auto-tune.
For the Bradley smoker with second heating element, we have done some tuning. The only parameter you need to change is the P value. It should be increased from 70 to 140. The rest of parameters should be kept the same as the original (I=600 and d=150). This will give you the best result.
Thanks,
Suyi Liu
Auber Instruments
So Auber Inst. is excellent
LTS