Heat Pumps and Electric Heating - Coleman 3400-A816 electric ac unit - HELP

I am having a problem with the insulated pipe on the inside freezing - see pics http://photobucket.com/albums/ll37/kamiller73 When this happens little air or non comes out of the registers. We've had it charged, changed filters and we are coming up on our regular 115 degrees for the summer:( . Please help... In the pics you see the pipe frozen and what the inside of the furnace looks like. I had someone come out and tell me that the upper part needs to be placed closer to the blower (at the bottom).:confused: Is this correct?? Any pics of what an inside looks like would be helpful also. Thanks and god bless...

Its best if you stay in one post. Are the fins clean in the blower wheel??? coil clean??;)