Heater problems

[dozrdog]

Took our new 2012 trailer out this weekend for the first time. Heater comes on but hot air is blowing from the vent outside the trailer and no air is coming through the floor vents. After reading the owners manual over and over again the only thing says to make sure swift valve is open. Where would that be at? That is the only thing we haven't tried. Desperate for any advice.
Thank you

[MtnGuy]

The duct work may have come loose, or been mashed shut....that stuff is flimsy at best.

On my trailer, you can't much if any airflow coming out of the vents, but the furnace heats the camper nicely.