What could be causing water to come into the passenger side floor? on 2003 Dodge Durango

Anytime I run the air or heat water will fill the floor. It is pure water with no antifreeze. I have been told its a condensation valve stopped up but have had no luck in finding it.

Asked by for the 2003 Dodge Durango
Your Evaporator case drain is stopped up. Its at firewall below evaporator case underside of body.
Do I need to remove the passenger side tire to get to the drain?
Probaly not...may have to raise it up to see it better.