the old f3 seems to be burning all or none lately. i put in a full load and in like 5 min I'm up to 600 + ill damper 1/2 way and nothing so i go all the way and it slows down. as soon as a push it back say 1/2 way it goes right back up to 700 +. I'm thinking its time to change the door gadget it passes the dollar test. but I'm thinking its the gasket on door really don't open the ash door much. i just peel off old one scape out glue put in new glue and then new rope and close let dry? right?