Hi Conrado, review two small details that can be the key to success. One is that the drain hose, always go slightly in fall or slope, from its beginning, through the rear outlet of the indoor unit, to the tip of its end end from the outside, the detail is that the hose, not It is forming waves or siphon, which can retain air with the water cap and not allow the free circulation of water through the drain hose itself. The second thing to keep in mind and rarely taken into account, is the detail that the grounding wires, which are made by the evaporator front of the indoor unit, as well as the sensor wires of temperature, these cables and sensors, must be placed making a kind of parabolas, obviously with the wave up, to avoid that through these cables, the water can slide, which distilled the evaporator and give rise to the constant drip that now has that equipment inside, the front cables and the sensors should not be left, touching the protective plastic housing, so that it also does not allow water to slide through them and transmit liquid through the protective housing. Take these details into account, and comment please. Luck. S @ lu2 friovega63.