I am new to this site. My new Defiant has a very restricted air inlet damper. Will not stay up to temperature wide open unless I crack open the ash pan. Excellent draft causes great heat up with ash pan cracked open. Inspected small rectangular oval damper plate. It only opens a crack before interference from inner stove plate. Not sure how to get and keep this big thing hit. I’ll include the photo of oval damper that hardly moves.