Did you confirm it is coolant or just water that is causing the carpet to be wet? Coolant leakage into cabin would have the radiator running dry, make sure you check the level.
Coolant would be from the heater core as answered by kng1818 but if it is just water, it could be the the AC evaporator (cooling coil) housing drain hose has been dislodged or clogged .
You would have to remove the dash to get at the heater core.
This is the heater unit under the dash.
Thursday, January 28th, 2021 AT 9:40 AM