64 53...Instructions for desiccant insert replacement

A desiccant insert that is in a correctly functioning, sealed heating and air conditioning system does not have to be changed at regular service-inspection intervals.

However, the dryer flask or desiccant insert must absolutely be replaced in the event of: 

• contamination of the refrigerant with debris (e.g. when the compressor is clamped).
• With depressurized and/or completely drained refrigerant circuit.
• With a refrigerant circuit, which was closed using special tool 32 1 270 but remains open for more than 24 hours.

The desiccant insert cannot be replaced in the following vehicles: 

• 1-Series E8x, 3-Series E9x  from 12/2008
• E84, E89 
• 1-Series F2x, 3-Series F3x 

In these vehicles, the condenser for the heating and air conditioning system must be replaced.