that coiled tube must the evap
It is a suction accumulator with a built in liquid line subcooler, the liquid line is fed through the coil.

The J-pipe is used to prevent liquid refrigerant from returning to the compressor. Not visible in the picture is the small (sub-millimeter) hole at the bottom of the J-pipe which allows oil to return to the compressor instead of building up in the accumulator.

Tom