FYI The evap temperature sensor is in the heater box behind the dash. It is NOT part of the sealed system that would require evacuation, and recharge to replace components. The sensor can be replaced without opening the system, but the mechanic may want to fully remove the heater box which would require opening the system. Ford recommends servicing the air conditioning system every five years. If the mechanic does open up the sealed system, they will need to replace the filter dryer in the condenser, and should also replace the o-rings in the lines.