The Mercedes SDL recommended refrigerant (R12 type) capacity is 2.8 lbs., or 1.27 kg. Some models may list a range of 2.2 - 2.9 lbs. It is important not to exceed the recommended capacity!
The air conditioner needs regassing
You need to to add more conditioner fluid in the system.
What is the difference between rated capacity and the nominal capacity
35kva
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134a refrigerant.
R 12
1999 E320 air conditioner work on first and second speed, after 3rd blow warm air. AKINOHD@YAHOO.COM
Did you check the AC fluid? That is sometimes the problem.
2 pounds four ounces
R12, unless it has been converted.
It`s rated capacity in sensible and latent heat.