I keep a record of what I smoke, the door temp., the meat internal temp. at the top rack and at the bottom rack, etc. I check it each 15 minutes and write all this down. I reviewed this and noticed that I usually do not get smoke until the door temp. is around 120-150 degrees on a warm day. However, on a day that was 53 degrees I started getting smoke when the door thermometer said 105 degrees and the meat temps were 61 degrees after I just started the smoker. Maybe on a cold day the smoker loses heat thru the walls and the heating element has to stay on more to compensate and that put more heat on the wood tray. I nearly always use hickory chunks to smoke with and add some very small mesquite that will heat up quicker and get the hickory chunks going. You might try smoking on a cold day and use finely cut chips and see if you get smoke at low meat temps. I also put the meat in a cold smoker and go from there instead of pre-heating as most folks do.