Complete 2 system a/c repair and preventative maintenance check. Change both filter, check drain and operations. Find upstairs system operating with rusted Coil and dirty molding plenum. High amp on motor and low on charge. Compressor start up slow and stress. Find downstairs system frozen and low on charge. Recharge system to manufacturer Spec and system cooling at this time. Both system 17-year-old with worn motor and need to keep check.