Low airflow through the indoor coil in cool cycle will primarily result in a reduction in low side pressure and saturated evaporator temperature. The system design requires the design volume of air (heat) to vaporize the necessary amount of refrigerant for the rated tonnage value. Ideal airflow is 350-450 cfm per ton. TXV metered coils will maintain the superheat setting but piston metering generally results in reduced superheat. The lower suction pressure increases the pressure differential across the piston which forces more liquid through the piston.
I got the system running at steady state, then reduced the airflow. The video shows before and after numbers.
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