Performed comprehensive AC maintenance on a residential unit. Checked refrigerant levels using a manifold gauge and added R-410A as needed. Cleaned condenser and evaporator coils with a foaming coil cleaner for optimal heat transfer. Inspected and tightened all electrical connections. Lubricated motor and blower bearings. Cleared the condensate drain to prevent water buildup. Replaced the air filter and calibrated the thermostat for accurate temperature control. Tested the system to ensure efficient and reliable operation.