MRCOOL GCNV-VD00-3834 GeoCool No-Vac Geothermal Pre-Charged 3/8" x 3/4" Lineset is a refrigerant line set designed to connect compatible indoor and outdoor geothermal HVAC components. It works by providing pre-charged refrigerant pathways for efficient circulation between the heat pump and connected equipment, eliminating the need for traditional field evacuation during installation. ... https://www.partshnc.com/mrcool-geocool-no-vac-vertical-downflow-3-8-3-4-pre-charged-lineset-gcnv-vd00-3834