I had major problems with my air conditioner last summer, which required a few new parts including a new circuit board and a new motor for the fan. Today, to my great dismay, I noticed that it wasn't working properly yet again.

However, I think the problem might be a minor one and I thought perhaps someone here might know the answer I'm looking for.
I just went outside and checked the compressor. The valve (is that the correct term?

) that connects to the hose that runs to the house was completely encased in a block of ice. I seem to remember that this was the problems on one of the occasions last year when I had the repairman come out. I was at work when he came; my dad came over and handled things for me. As I recall, it was a relatively easy fix, but I can't remember what it was. I think it may have been caused by an obstruction that caused the ice to form, which in turn, prevents the air from coming through the vents inside the house. I chipped away as much of the ice as I could with a hammer. I turned the unit off and the rest seems to be melting. I'll switch it back on once the ice is completely melted. I vaguely remember something about the need to switch the fan to the ON position instead of AUTO. Is there anything else I should try?