Hummm!! it Seems it is a known problem with Mercedes from 94 to 98. Is two problems
La mercedes auto asa este.mijlocu sufla intotdeauna aer rece.
The 2000 Mercedes C280 air conditioning compressor fuse can be found in the fuse box. The air conditioning compressor fuse will be in the second column, fifth from the bottom.
This is a common question for new owners of Mercedes 190e. The center vents only blow outside air and conditioned air from your a/c. This is the design of the system. The reason Mercedes made it this way is to keep the driver alert and awake. You can adjust the flow of air from the center vents by moving the slider up or down, but the air will always be the ambient temperature from the outside or from your a/c when it is engaged.
evaporator can get plugged up--stays wet all the time & gets to rotting & moldy --should be cleaned or replaced
The blend door actuator may not be working.
The air of your Chevy trailblazer 2004 blow out of the front vents when the air conditioner is on because the air condition is faulty and it needs repair.
The HTR RR switch in a Kia Sedona determines which air vents the air is blown through from the rear heating. When it is pushed in, the lower vents blow hot air, and when it is not pushed, the roof vents blow cold air.
If the air vents of the Chevy trailblazer 2004 are not blowing air, have the fuel pump checked.
Possible blockage in the rear air units expansion valve. I just replaced mine for the same reason.
air want blow out vents
Your front blower motor has gone out. There is a front and a rear blower motor.
Moisture in the air condensing into mist.