Why is your home air conditioner blowing air but no cold air is coming out and the outside line from the unit is icing over?

The Freon may have lost its ability to cool or the Freon may not be circulating due to a faulty pump. Freon does not loose it's ability to cool. There is either insufficient Freon for the size of the system indicating a leak, or the pump is wearing to the point where it can no longer provide sufficient compression of the gas. In either case, a trained tech is required and should be able to provide an immediate diagnosis.