Air Conditioning (A/C) System Recovery, Evacuation and Charging

1. Unscrew and remove the protective caps from the A/C charging connections.

CAUTION: The refrigerant identification equipment must be used before the system is emptied, otherwise the service unit may become contaminated. Contaminated refrigerant must be disposed of as special waste. The manufacturer's instructions must be followed when working with the service unit.







2. Pull back the catch of the quick-fit union on the line of the service unit.
3. Connect the service unit line to the A/C charging connection.

NOTE: Larger inner diameter for high-pressure side. Smaller inner diameter for low-pressure side.

4. Empty the air conditioning system through the low-pressure connection according to the instructions of the service unit manufacturer.

WARNING: WHEN RECOVERING THE REFRIGERANT DO NOT ALLOW IT TO ENTER THE ATMOSPHERE UNDER ANY CIRCUMSTANCES.

5. Evacuate the air conditioning system according to the instructions of the service unit manufacturer.

CAUTION:
- The air conditioning system must be evacuated for about 30 minutes before recharging it, to ensure that it operates correctly.
- If moisture was able to enter an open system over an extended period (several hours), install a new accumulator/dehydrator and increase the evacuation time to 2-3 hours.

6. Perform the leak test. Component Tests and General Diagnostics
1. For the leak test, close the manual valves on the gauge set, switch off the service unit vacuum pump and watch the low pressure gauge.
2. If there are leaks, charge the air conditioning system with approx. 300 g of refrigerant and check it using leak testing equipment.

NOTE:
- If an air conditioning system that was filled with refrigerant is being evacuated, then some refrigerant will still be in the refrigerant oil in the compressor. This residual amount of refrigerant may still evaporate and during the leak test may result in a slight increase in the pressure gauge reading (max. two subdivisions). However, despite this pressure increase the air conditioning system is free from leaks.
- If the gauge reading increases by more than 20 mbar (2 kPa or 0.29 psi), the system is leaking.

7. Refill with refrigerant oil.







8. Charging the air conditioning system (with liquid) through the high-pressure connection.
1. Open the shut-off valve on the high-pressure side.
2. Switch the service unit to "Fill" mode and charge with the prescribed quantity of liquid refrigerant (R134a).

CAUTION: The air conditioning system must always be evacuated before charging.

NOTE:
- Depending on the type of service unit and the variant (with or without heated filling cylinder), the air conditioning system is either charged with liquid through the high-pressure connection or with gas through the low-pressure connection,
- Charge quantity on sticker in the engine compartment.

9. Charging the air conditioning system through the low-pressure connection.
1. Open the shut-off valve on the low-pressure side.
2. Switch the service unit to "Fill" mode and charge with gaseous refrigerant.
3. Add the remaining amount of refrigerant with the air conditioning switched on. To do so run the engine at about 1200-1500 rev/min. Set the air conditioning system to full cooling power and fresh air mode. Set the blower to full power. Charge with the remainder of the prescribed charge quantity.

CAUTION: Only gaseous charging of the air conditioning system is done through the low-pressure connection.

10. Disconnecting the service unit.
1. Close the shut-off valve.
2. Switch off the service unit.
3. Disconnect the service unit line from the A/C charging connection.
4. Screw the protective caps onto the charging connections.

WARNING: DO NOT DETACH THE HIGH-PRESSURE HOSE WHEN THE AIR CONDITIONING IS SWITCHED ON.