Tech found system low on refrigerant and found coils not leaking. The only leak present was at the schrader valves, but tech suspect the lineset is leaking due to insulation worn off and how it was buried in the dirt going under the house. Tech recommends replacing unit due to r22 refrigerant and likeliness of future issues. Tech quoted replacing schrader valves and recharging up to 5lbs of r22. Quote does not include replacing line set. Customer agreed to replacement quote before making a decision. Field supervisor has been notified.