went on a no cool call, found a 410a split system operating -5 psi at suction and 18 psi at discharge, turned the system off and standing pressure was 0 psi both sides. no low pressure switch installed. does this mean the compressor was pulling in air from the leak point that caused the refrigerant to leak out? is it worth finding the leak, repairing, changing filter drier, and recharging to see if compressor still holds up? thanks for any guidance