| General Procedures Refrigerant centre Refrigerant identification equipment | | -
CAUTION:The refrigerant identification equipment must be used before the system is emptied, otherwise the refrigerant centre may become contaminated. Contaminated refrigerant must be disposed of as hazardous waste. Always follow the manufacturer's instructions when using the refrigerant centre and the refrigerant identification equipment. Unscrew and remove the protective caps from the A/C charging connections. | | | -
Pull back the catches of the quick-fit unions on the refrigerant centre lines. | | | -
NOTE:Larger inner diameter for high-pressure side. Smaller inner diameter for low-pressure side. Connect the refrigerant centre lines to the A/C charging connections. | | | -
WARNING:When recovering the refrigerant do not allow it to enter the atmosphere under any circumstances. NOTE:When removing components of the air conditioning system, calculate the residual quantity of refrigerant oil. For additional information, refer to Refilling refrigerant oil in this section. Empty the air conditioning system through the low-pressure connection according to the refrigerant centre manufacturer's instructions. | | | -
CAUTION:The air conditioning system must be evacuated for about 30 minutes before recharging it, to ensure that it operates correctly. CAUTION: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. Evacuate the air conditioning system according to the refrigerant centre manufacturer's instructions. | | | -
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 remaining refrigerant may evaporate, causing a slight increase (max. two marks) in the reading on the pressure gauge during the leak test. However, despite this pressure increase the air conditioning system is free of leaks. NOTE:If the gauge reading increases by more than 20 mbar (2 kPa or 0.29 psi), the system is leaking. Perform the leak test. - For the leak test, close the hand valves on the gauge set, switch off the refrigerant centre vacuum pump and observe the low pressure gauge.
- Locate any leaks in the A/C refrigerant circuit using a leak tester.
For additional information, refer to Leak detection with electronic leak tester /
Leak detection with fluorescent tracer dye in this section.
| CAUTION:The air conditioning system must always be evacuated before charging. | | -
NOTE:Depending on the type of refrigerant centre and the equipment (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, NOTE:Charge quantity on sticker in the engine compartment. Charging the air conditioning system (with liquid) through the high-pressure connection. - Open the shut-off valve on the high-pressure side.
- Switch the refrigerant centre to "Fill" mode and fill with the prescribed quantity of liquid refrigerant (R134a).
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CAUTION:Only gaseous charging of the air conditioning system is performed through the low-pressure connection. Charging the air conditioning system through the low-pressure connection. - Open the shut-off valve on the low-pressure side.
- Switch the refrigerant centre to "Fill" mode and charge with gaseous refrigerant.
- Top up with the remaining amount of refrigerant whilst the air conditioning is switched on. Let the engine run at about 1200-1500 rpm for this purpose. Switch the air conditioning to maximum cooling power and fresh air mode. Set the blower to full power. Fill with the remainder of the prescribed fill capacity.
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WARNING:Do not detach the high-pressure hose when the air conditioning is switched on. Disconnecting the refrigerant centre. - Close the shut-off valves.
- Switch off the refrigerant centre.
- Disconnect the refrigerant centre lines from the A/C charging connections.
- Screw the protective caps onto the filler valves.
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