AC tune up on upstairs and downstairs systems Blower and coils slightly dusty Drain lines are clear Biological growth present in the supply plenum of both systems - should be eliminated with an anti microbial mist and UVC systems Temperature delta on both systems are fine Washed condenser coils off both Condenser fan capacitor is nearing failure and should be replaced ASAP all other components tested fine Homeowner will consult his home warranty company and get back to us