Just purchased a used High Valley 2500 in great shape for a great deal. Got it installed and for some reason, It will not keep a fire. When I close and latch the door, it smothers out the flames. My chimney is drawing like it is supposed to, so I dont know what is wrong. Anyone have any ideas? I cleaned the insert before I installed and blew out the air intakes, but now I am out of ideas. Any help would be greatly appreciated. Thanks.