Where is the drain line located on a mini split?

The condensate drain line on a ductless mini-split system originates at the plastic drain pan located directly beneath the indoor wall cassette unit. From that internal pan, a flexible condensate drain hose exits the housing through a small hole in the wall, running alongside the insulated copper refrigerant line set either outdoors to a safe gravity termination point or indoors to a condensate pump reservoir tank. You can troubleshoot blockages visually by inspecting where the drain pipe exits the exterior wall or connects to the pump. You can verify that your drain line is correctly located and functioning when water produced during cooling cycles flows unimpeded out of the tube without backing up or leaking inside your living space, protecting your walls and floors from water damage.