Thanks for heads up Peter. I don't have the air-con option and I don't have any issues with heating other than there could be a little more in reserve during winter. I do note that during heavy rain in summer with shorts on, you can feel spits of water through the cabin vents when on the move, presumably entering heater box from bonnet louvres.
That aside I have no reason to suspect the heater box drains aren't working as intended.
