Mercedes-Benz W210 A/C refrigerant leaks and dryer
Where does the W210 A/C refrigerant usually leak from?
Most often from the condenser and its connections. Other leak points are a rusted dryer, O-rings, the evaporator, the service valve, chafed hoses and the compressor shaft seal. An oily spot often reveals the leak.
How is a small leak found?
The most reliable way is to pressure test the system with nitrogen. A vacuum test does not always find a leak, because the vacuum can seal an O-ring. When there is little refrigerant, the compressor runs but cooling is weak; when the refrigerant runs out, the compressor does not start.
Does the dryer have to be replaced?
The dryer should be replaced whenever the system is opened or parts such as the condenser are replaced, and it must be the correct type. The dryer absorbs moisture, so it should not be left open for a long time. A blocked dryer shows as a large temperature difference between its inlet and outlet lines.
How much refrigerant does the W210 A/C take?
According to several sources the system takes 1000 g. The refrigerant is recovered before the system is opened. After replacing the condenser and the dryer, oil is added according to the amount of oil recovered.