The problem would Most likely be that your A.C. Needs to be Recharged.. You can buy a kit at ur local AutoZone for about 15 bucks!
The heater core valve is probably sticking or adjusted wrong.
There is a door behind the dash that changes cold and hot air flows. The door is probable stuck or the control circuit has failed causing the hot air to blow on cold.
Check into the temperature control valve--this is different than the thermostat.
Temperature control set to heat?Needs refrigerant charge?
Check temperature control cable for binding.
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The control for the heat on the dash has a control for the back seat and also has a setting that says something like "Rear Control". This allows the passengers in the back seat to control their heat independently via a temperature control in the back seat (on the back of the center console). So you could have the heat on in the front and the rear on "rear control" and if the passenger in the back has set their control to cold, it wold blow cold air in the back even though you have the heat on in the front.
Try replacing the temperature control switch for the rear control cluster. Hope that that's the fix. Less than $20.
Wind can blow from any direction. Please clarifi. -Jonhis
Blow Up the Outside World was created in 1995-11.
There is no 1995 ford Expedition!
Blow by is caused by internal engine problems. You need a new engine.