Help with outdoor A/C unit?

The pvc pipe is the condensate drain for the evaporator. As warm moist air from inside the house passes over the cooling coil, moisture in the air is condensed and must be allowed to flow away. The pipe actually should have a p trap installed on it. It is important that the condensate be allowed to flow away from the unit. It will be ok flowing onto the ground, but it must be free flowing. Without the drain line, air will be sucked into the opening in the unit and water will build up in the condensate drain pan until it spills over and begins to damage the unit's casings. The water also provides a perfect place for microbes and bacteria to grow, possibly exposing the occupants to unhealthy air quality.