It's too hard to tell, since a warm driver's side on a W210 almost always indicates low charge. You really should hook up a pair of gauges and report back with the pressures. If you don't own a set, AutoZone rents them (at least the one by me does). They'll be grungy and oily, but they'll work and will give you a general idea of the state of charge of your system.

It's also possible that your duovalve is stuck in the "on" position for the driver's side, but again I would rule out the possibility of low charge first.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280