front ac fan blows hot while rear ac blows cold. help on 1997 Ford Expedition

when we turn on either AC or MAX AC the rear vents work fine and are cold, but with the front vents we only get cool air when the fan is on the low setting. If we turn up the fan to any other speed it starts blowing hot air. Please help--we are sweating! :)

Asked by for the 1997 Ford Expedition
Really need to have your Climate Control System inspected, which has its own Computer to control the A/C system. The fact that it does not blow warn air all the time, says that it could be a control issue, because if the system had a leak, it would never get cold. Find a a shop who knows A/C and Climate Control Diagnosis.
1 more answer
try the blower