Hi all. This is my first time on here. I'm working on an '86 Airstream and just replaced the original furnace with a Suburban NT-30SP. It is overheating and I'm thinking the ductwork might be blocked or kinked. I can trace all the duct lines except for two 2" ones. One goes straight down from the furnace and toward the front of the trailer (to keep a tank warm??). The other goes down below the floor from the middle closet (where the water pump is) and disappears. Anyone know where these go, and if it's possible to replace them without pulling up the floor??
I guess the other questions is: Is there any other reason the furnace would overheat? Voltage to it is good, I had the cabinet door off when measuring discharge air temps (they got up to 250 F at the closest register) so return airflow is good.
Thanks for any help! Nathaniel