It has been running in cool in the summer (and we have a long, hot and humid summer) here in Cyprus and in the winter in heat mode.
no watermarks or other leakage sign anywhere.
and yes the empty space is for a future unit kamersoutdoor, that picture is from another room.
well thanks everyone for the help, It's still a mystery to me where the drain goes but since in 6 years there is no sign of water damage I think everything is prob ok.

