AC performance tune-up times two systems. Inspect blowers, evaporators and ductwork. Filters do need to be changed and tenants are aware of this. Had to install two quick blast isolator valves to clear the primary drains. Both of them were on the verge of being backed up since they tee together to one common drain. Check outdoor units. Downstairs condenser needs a run capacitor. It is below Factory specifications. Upstairs is low on refrigerant. It is 15 years old and it is r22. Washed both condenser coils. We will wait for Vicky's call back to see if we can come back and install necessary parts and refrigerant.