Abstract: The air conditioning unit has a refrigerant evaporator diagonally disposed within the air conditioning cabinet and includes a condensate drain trough at the opposite edges of the evaporator adjacent the front and rear wall of the cabinet, a drain pan assembly extending along the rear wall of the cabinet, and a detachable drip tray which is located in one position on the upstream face side of the evaporator when the cabinet is in a vertical disposition and is located on the upstream face of the evaporator in another position to feed condensate to the other drain trough when the cabinet is in one of its horizontal dispositions, the relationship between the two drain troughs, drain pan and drip tray accommodating the installation of the cabinet in a vertical disposition, and alternatively in a horizontal disposition with either the front or the rear face of the cabinet on top.