Diagnosed and repaired Rheem RCFL-HM3617CC air handler. Identified failed ECM blower motor using GE TECMate PRO diagnostic tool. Replaced with OEM UltraTech 51-104305-04 variable-speed motor. Programmed new motor to match system specifications: 1200 CFM, 0.5" ESP. Verified proper communication between thermostat and air handler control board. Tested system operation across all fan speeds. Airflow and energy consumption now within manufacturer parameters.