This thread is about ten years old. You'd think that by now, Cookshack would have resolved this issue.
Just experienced this issue with my SM045 smoker. Ambient temp was about 90f outside and the control system was in direct sunlight. Got the HOT led warning. Covered it with a towel and it started working again.
Thank you all for this thread. It let me know quickly what the issue was.
The Cookshack folks really should redesign this.