Assuming your temperature selector is not on "cold", the heater core is likely bad
This is a big job.. Get a manual on your car from DISCOUNTAUTOREPAIRMANUALS.COM .
you would have to see a mechanic about that problem
Behind / below the glove compartment area inside a plastic case . You can see where the heater hoses connect to the heater core at the firewall in the engine compartment
Behind the glove compartment area inside a plastic case . From the engine compartment you can see where the two heater hoses connect to the heater core at the firewall
Your heater core is leaking in it's housing box and blowing moist air through the heater/defroster. Try bardall radiator stop leak. If no help, install new heater core. Chuck.
Mercury Mountaineers have a "blend" door in the heater box. It is probably malfunctioning. You can find more info by searching for Ford + "blend door" or "no Heat"
Jump start car and do not run heater with engine not running.
Probably because coolant level is low
A bad heater core / it needs to be replaced
Why the heater or defroster may not work in a 1993 Chevy Caprice Classic because of the heating core is going out.