Air-conditioning tuneup. Customer also stated upon arrival that it did not seem to be cooling as well as it should be. I washed out the condenser coil. I checked the contactor and capacitor. The capacitor is reading 34 out of 35 µF. I flushed out the condensate trap and check the media filter. I cycled the system and found that it was low on charge. I added 6 lbs. 8 oz. of refrigerant 410A. This brought the system to 11° of sub cooling. System is operating properly at this time. There is no warranty or guarantee for adding refrigerant . I found that the service valve caps were loose on the condenser. If leak reoccurs I recommend performing a leak search and making repairs to the system or adding a leak stop to the system.