Hi! I do not know the proper name for any of the A/C parts, so please forgive me in advance:o. Our A/C does not seem to be cooling very well after it's been running a while. When I went outside to check on it, I noticed that there is ice forming on the pipe that goes from the unit to the inside of the house. This pipe leaves the unit from the bottom corner in back and travels up the side of the house through a hole to the inside. There was originally some black insulating material wrapped around the pipe and secured with plastic ties. Some of this material has come off (close to where the pipe leaves the unit and at the curve where the pipe begins to go up the wall.) The icy parts of the pipe are where the insulating material is missing. Could this ice be the cause of the cooling problem and is the missing insulating material causing the ice to form? We have been leaving the unit off a while each time we notice the ice and it seems to cool better after that. Should we try to replace the material first before calling for help? Thanks!