Performed AC Diagnostic on 2020 Lennox condensing unit. Upon my diagnostic customer stated that one supply vent Located in the kitchen was not blowing as hard as it should compared to the other. Located S 30 I comfort thermostat and ramped up CFM’s on high and low stage cooling mode, Also adjusted rossi damper running to downstairs. System Had a 18° split And airflow was increased in velocity through weak supply vent. This may due to the long chase the supply duct has to run down due to It being A downstairs Duct Run. Also installed 8x4 supply Grill upstairs in the master closet. Upon my departure system is fully operational and cooling with better airflow.