2002 f150 no heat to the floor setting,,

Question

I have the 2002 f150 supercrew with the 5.4 triton,my heater wont push heat or a/c to the floor,it will only push about 10% to floor and 90 % goes to the windshield,,all other seting work as they are suppose to,,it has the digital system that does not have turn knobs,its all push button,with outdoor temp and the digital read out for temp and so forth,,please,,any help is needed,,cold times around the corner,,lol--thanks chuck