very sadd
I only read in this post a few times about ductwork. Everytime a furnace is installed, the ductwork must be checked to see if it can deliver the apropriate CFM. In my area, "pro's" have constantly dissapointed me in that they will put a furnace in and tie on 14" Flex for a return. they don't seem to grasp the fact that you have to maintain the temperature rise designated on the furnace rating plate. generally speaking, you never want a temp. rise over 60*. but every unit has there own design temp. I guarantee your problem is in the ductwork, not saying you might have a few other problems, but the ductwork is KEY. I take it that this furnace has been overheating from day one, make sure the pro you call is in fact a pro, and have them check the eyelets on your heat exchanger, because I will gurantee they have busted.
Pay me now, or Pay me Later,
Pay me more if you pay me later
What if this is as good as it gets?
Jump, Tuck, and Roll. WHOOAAAH