Performed preventative maintenance for a carrier rooftop package unit. Model #48TCEA05A2A5A0A0A0, serial #1811C03801. I removed the access panels and removed the air filters size 16x25x2. I installed 2 new air filters. I tested the drain to ensure that there are no clogs. Checked all the electrical connections to ensure that they are secure and in good condition. The belt is in good condition as well. The manager repots no issues with the system. The system is operating properly at this time. No charge CA.