Working With A/C Service Station

Working With A/C Service Station

Important Notes

Observe the following with regard to A/C service station operation (e.g. V.A.G 1885).
- The filters and dryers installed must be replaced at the latest on completion of the service life specified in the relevant operating instructions.
- If an A/C service station is also used for flushing the refrigerant circuit, dryer and filter must be replaced in shorter intervals.
- Exclusive use is to be made of refrigerant oils which have been approved for the vehicle-specific refrigerant circuit (if necessary, fill refrigerant oil directly into refrigerant circuit).

Extracted refrigerant is not to be reused if there is any doubt about the composition of the refrigerant extracted, even after cleaning in the A/C service station.
- The A/C service station is to be drained in all these cases, the system cleaned if necessary and the filters, dryers and refrigerant oil replaced.

Commercially available A/C service stations can be classified in 2 groups:
- A. A/C service stations which clean extracted refrigerant for re-use (so-called extraction and recycling stations), e.g. V.A.G 1885 currently available A/C service stations)
- B. A/C service stations which transfer extracted refrigerant to recycling containers (for large-scale recycling). These are referred to as extraction systems.

Connecting for Measurement and Testing
- Work procedure may vary depending on the type of tools selected (the tool-specific operating instructions should therefore be followed).

NOTE: The work procedure is always to be performed as described in the operating instructions for the relevant A/C service station (e.g. V.A.G 1885).

The charging hoses are to be connected as follows to prevent the ingress of air or moisture into the refrigerant circuit:
- Switch off ignition.
- Connect A/C service station to power supply.
- Unscrew caps from service connections or connections with valve (refer to vehicle-specific refrigerant circuit).
- Evacuate charging hoses if necessary.
- Connect quick-release coupling to service connection of refrigerant circuit.

CAUTION: Never open valves on low or high-pressure side with engine running, as otherwise compressor or A/C service station could be destroyed by a short circuit between high and low-pressure sides of refrigerant circuit if air conditioning system is switched on.

NOTE: Screw valve adapters V.A.G /9, V.A.G /10 or air conditioning adapter set V.A.G 1786 to refrigerant circuit connections with valve and bleed charging hoses during connection to adapters (faintly audible escape of refrigerant gas is permitted).

Vehicles with one service connection only:
- The charging hose must be installed with a valve opener for opening valve in valve adapter.
- Only screw handwheel into quick-release coupling adapter to the extent required to reliably open valve in service connection (observe pressure gauge; take care not to strain valve).
- Start engine and perform planned tests and measurements.
- Compare values determined to specified measured values.
- Before disconnecting quick-release coupling, close it by screwing out handwheel.