what would cause only cold air out of drivers side vents. on 2006 Kia Amanti

Temp is set at 65 deg. Heat comes out of Passenger side and rear vents. Blower appears to work fine.

Asked by for the 2006 Kia Amanti
Turn temp. up! Dual climate control? Drivers side is colder as it is further from heater core. My opinion only, i could be wrong.
Can't be that many BLEND DOOR problems!
2 more answers
blend door issue seek diag from your mech
seek diagnostic, it could be the blend door switch