I have had to take the grill apart and clean it out each time. When I remove everything the pit is full of pellets but only a small amount of ash in the bottom... I always preheat to 225-250 before putting into smoke mode but it goes out within the first 30 minutes of switching, then the pot fills completely full of pelletsWhen I have this issue it is always because I have too much ash in the burn pot. I don't know how the 1100 is set up to clean out the burn pot but that is where I would start with my shop vac and get all the ash out of the entire grill.
Hmmm well it is brand new... literally one week old... not sure how to check everything you mentioned.Also check the air path from the fan to the burn pot and make sure it isn't restricted. If it is restricted it would explain why higher heat works and lower heat (smoke setting) does not.
I will do that. But when it goes out I find the fire pot overflowing with pellets.Here is what I recommend is to take every out of the grill and run it. Just do you normal process start at smoke run it to the smoke clears then increase it 225 - 250 to preheat then set to smoke. Watch the temperature very closely once it is below 200 open the lid and see if the auger is feeding pellets into the fire pot and pay attention to the feed rate. If it is not feeding then you have a bad controller since it is not recognizing proper temp set.