inside cabin will not warm up, hear vents opening, blower blowing, motor running, just enough warmth to clear snow/ice from window after 15-20 minutes of running
no heat on 1998 Dodge Durango
I would start with replacing your thermostat and coolant. Inspect all of your cooling system hoses and replace if Soft or swelling, hard or brittle. You can remove both heater hoses from the heater core and run water through it with a garden hose to make sure the heater core is not plugged up.