my 1992 cadillac brougham 5.7 v8 heat doesnt work need help!?

[live life to the fullest]

my car is air condition is set at 90f to the hottest temperature but yet it only blows cold air and air doesnt come out the vents that hit your face only from the top and floor? and i filled the coolant to the full mark and in 2 or 3 days it dropped to the add mark. i dont see any fluid on the ground but its prolly because its freezing out here in chicago what do you guys think it can be?

 

[Handyman]

If you are loosen coolant your heater core maybe bad and you may need to have it replaced. If the heater core is leaking your carpet on the passengers side floor will be wet from the coolant . This maybe why your not seeing any leaks on the ground, because it's leaking in the inside of the cars.