Can someone please advise me. I have a 14 year old unit. (under the home, split system) It froze up on us. My service tech added freon and said we were ok. This year he said I have a small leak . He used a sniffer under the home, I was there and didnt see the leak register, he said I was leaking and should replace the unit under the home, for $. He said almost all units this age have this problem. OK, but what do I do going forward?. Replace the unit, or go new for the entire AC? Anyone have this issue?