My son has a place abroad and new Ariston airconditioning units have been fitted above the doors in three rooms. When the villa was being built I noticed the pipes being laid in the walls to the big AIRCON box outside and to the smaller boxes sunk in the walls. From photos I took at the time it looked like there were about four tubes/pipes going to each unit although some seemed to have just two but couldn't be sure due to plastering etc. His next door neighbours house built at the same time has water on the floors inside and the walls are turning black with damp near rthese units and a local plumber has stated that there are no outlet pipes on this chaps unit for the condensation that builds up. It is apparently draining into the wall!!! My son is rarely is there because of work so hasn't had the aircon units turned on but is very worried that if they were, this problem could also be in his house. I am flying over this week to take a look and would be very grateful if someone could let me know what to look for. Should all the units in the rooms have four pipes connected, is the 'drain' easy to find or see if it is connected. I am assuming that all aircon units should have a drain pipe as I have no idea. Will there be an outlet pipe outside or will it be connected to the drains outside underground. The house is a good decently built house so am surprised at this but am hopeful his aircon units and pipes are all correct. If you could let me know how to do some simple checks it would take a load of my mind.