E420 '97 Driver Side AC Problem
 

I have 97 E420. This summer started having problems with driver side of AC. Right side (not driver side) blows cold ac air , however driver side blows room temperature air. I replaced the AC thermostat last year and checked the AC system pressure couple of days ago, everything seams to be OK. I'm sure I'm not the first person with this kind of problem wondering if people can give any advice.

Monovalve is probably broken.

On W210 chassis when the refrig R134a charge is low, the left side will be warmer. Have refrig charge checked!!