Ac will blow very cold from floor vents will not blow through dash vents

SOURCE: The air cond blows out of the floor instead of the vents

i dont know if you have checked the vacuum lines underneath the dash but my truck was doing it after i replaced the heater core and i come to find out that it was the vacuum line that comes through the fire wall that was disconnected. after i hooked it back up it started working right again.

SOURCE: 2003 dodge caravan air vents will not change position?

I HAD THE SAME PROB WITH MINE I REPLACED THE HEATER CONTROL PANEL & IT FIXED IT

SOURCE: ac will not blow thru ac vents, only thru defrost vents.

if vent doors are operated by vacuum check for loose or broken vacuum hoses in the engine compartment , or check the fuse box for any ac/heat fuses if it is a electricaly controoled system

SOURCE: air blows out dash vents but not with the force it

Either the flap that switches positions from floor/defrost/vents is stuck, or a vacuum line has came off, or there is a nest or other clog either in the fan's squirel cage or in the vent itself

SOURCE: ac does not blow thru dash vents very hard just a

Dodges have issues with the plenum door actuators. You can read online for more information. Sounds like your plenum door either stopped where it was or went to a default ( closed) position. The plenum door mixes the air and moves to allow the desired temp air to pass thru it.
I think you can see the tip of the actuator shaft sticking down vertically from the bottom of the plenum box, just to the right of the transmission hump, where the passengers left toes would be. Most likely you will have to remove the complete plenum for repair. ( pain in the a**). Good luck.