while starting my Pro Series 820 last night, It got to temp 165 then noticed the temp gradually decline. The hopper was full of new pellets. After watching the temp gradually drop, I shut the smoker down and pulled the everything out to look at the burn pot. I found it full of pellets, to the point it overflowed into the barrel. I am not sure of what could be the cause of this. It should also be noted that the pot and grill was just cleaned as well before use. Could this be a faulty fan?