DM066 smoking temp too high

How long after you started the smoker did you notice this? There is a pre-programed start up period. The temps go to max for 30 minutes or so. This is to get the smoke rolling and the temps inside the smoker up. There is also a small tube looking thing that sticks out of the inside back wall. Make sure that you don't have this sticking into your product, or real close to it.

Thanks Mike. It was 8+ hours into the cook when I noticed it. I turned the unit off and then back on and it went back to 225 degrees. I'll double check that small tube. I was spraying the butt with apple juice. I assume that would not cause an issue with that tube?

How long have you had your smoker? That tube is actually the temperature sensor for the smoker. If you get it buried into a butt or brisket it plays havoc with how the temps run. It can also get crud built up on it and that effects the temps. I assume that your cook is done. I would take everything out of the smoker, start with a cold smoker, and run it for several hours. Keep an eye on the temps. See if they don't stabilize and stay that way. Spraying the butts was probably not the problem. Opening and closing the door might have caused this.