,99 Tahoe front carpet soaked

When I run the a/c , water (not antifreeze) is constantly dripping from under the dash and soaking my carpet .I thought it was because the heater valve was not working so I tie wrapped it closed ( rarely need it in Houston ) . Cleaned drain plug and it drains well , pulled glove box and the whole housing for the heater core and evaporator is pouring with condensation . We do have high humidity here but something else most be goin on . Checked vent door ,it's closed ,heater door closed .evaporator fins where completely clogged but cleaned them .This is not a little moisture , more like a 1/4 cup puddle in 20 minutes , Any ideas please