Water on drivers side floorboard

2001 Volvo S80

I have water buildup on the floorboard of the drivers side. It does
not have a particular smell to it, oil or antifreeze, and seems to
occur when I use the heater.

I can not see water running down the firewall or sides of the
floorboard, but in the rear, under the break, the water seems to
collect more.

Any ideas where to look or what this could be?
Tim

 

The most obvious thing to do is unblock the drain for the air
conditioner. There is a drain that lets the condensate and other water
in the heating/cooling system escape. It can get blocked with road
debris. It needs to be routinely cleared.

You might thing you are not using the AC, but any time you have the
defroster on, the AC is on. Also, rain water and snow that gets into the
air intakes gets vented out this same drain.