Air conditioner

It sounds like the drain tube for the evaporator is plugged, when the ac is running you should notice water dripping from underneath the car, which is normal, if you dont, the drain is probably plugged and that is why your floor mat is wet. Look under the hood against the firewall where the ac lines go in, right in that area will be a little drain tube that sticks out of the firewall, that is the drain, take a piece of wire about 12 inches long or something similar and stick it in there to clean out any debris blocking the drain. Water will come out once the obstruction has been cleared.