Mercedes: E280 AC problem, interior climate, vacuum switch

Question
Mr.Robert , I have a 2007 model E280 Sedan. The problem is one side of the AC vents(left side) doesn't work properly . Takes long time for cooling and initially hot air blows. Where as the right hand side AC vents work fine giving cold air in a short duration even if it's hot. So i can understand there are 2 compressors for the AC system, one for the left and the other for the right. So i would like your opinion/advice on this issue.

thanks

Answer
Anish,
I have never seen a Mercedes with two compressors. The system generally have one compressor one evaporator inside the dash,  and one condenser in front of the radiator. The interior climate control is handled by a number of sensors and vacuum servos.
The cold air off the evaporator is mixed in accordance with the thermostat for each side separately.
I would begin to look for a servo that is not holding vacuum or for a hose, or vacuum switch that is defective.

In general, the sequence begins at start up. The computer will keep any blower action from happening until the evaporator reaches a predetermined temperature.  This keeps one from getting a cold blast of air in the winter or a hot blast in the summer.
Once the thermal sensor reaches the proper temperature, the computer brings the blower on line at full blast under overridden by a control knob on the dash.

I suggest that you check the vacuum system first.

Good Luck, let me know if I can be of further help.
Robert