The MRCOOL GCNV-VU00-3834 GeoCool No-Vac Vertical Upflow 3/8" x 3/4" Pre-Charged Line Set is designed for compatible GeoCool geothermal heat pump installations with vertical upflow configurations. This pre-charged line set connects the indoor and outdoor components, allowing refrigerant to circulate efficiently between the system’s heat-exchange components. Its no-vac design helps sim... https://www.partshnc.com/mrcool-geocool-no-vac-vertical-upflow-pre-charged-line-set-gcnv-vu00-3834