Performed preventative cooling maintenance on outdoor Lennox AC condenser unit. Changed indoor air filters. Checked the following: -Amperages on compressor and outdoor condenser fan motor. -Dual run start capacitor for the compressor and fan. -Contactor and proper voltage. -Refrigerant circuit for proper flow. -Thermostat functionality. -Proper air flow/temperature split from supply and return vents. System is cooling well at this time with a temp split of 16°.