Refrigerant Circuit, Charging
The entire refrigerant capacity can be filled either in the high or low pressure side, the following describes the charging the refrigerant circuit on the high pressure side.
Capacity for refrigerant and refrigerant oil. Refer to TECHNICAL DATA .
- Perform the procedure as described in the A/C Service Station's service/repair/system information. Refer to A/C Service Station's service/repair/system information.
- Before charging the refrigerant correct the quantity of refrigerant oil. Refer to TECHNICAL DATA .
- Make sure the A/C Service Station is on the same level as the vehicle whose refrigerant circuit is to be charged (maximum difference 50 cm (1.69 oz)) when charging the refrigerant circuit. If a difference in height is too large, a difference between the amount of refrigerant displayed on the service station and the actual amount filled in the circuit may result (depending on the version of the A/C Service Station). The filling precision of the A/C Service Station may change.
- The refrigerant circuit is completely assembled. Refer to REFRIGERANT CIRCUIT .
-- On vehicles with high-voltage system, switch on the "parking air conditioner" function (deactivate). Refer to the service/repair/system information.
-- Switch off the ignition.
-- Connect the A/C Service Station to the power supply.
-- Check and if necessary correct the refrigerant quantity, the quantity of refrigerant oil and the quantity for the UV additive for leak detection in the A/C Service Station. Refer to A/C Service Station's service/repair/system information.
Additionally on Vehicles with Electric Operated Valves in the Refrigerant Circuit, which cannot be Opened without Power:
For vehicles with a high-voltage system and additional A/C system functions ("heat pump operation" or "cooling the high-voltage battery"), valves may be installed in the refrigerant circuit that cannot be opened without current. These valves are opened and closed for example via a step motor and after switching off the ignition are no longer activated. To completely empty the refrigerant circuit or correctly to evacuate or fill, no areas may be closed. For this reason these valves must be opened before these procedures. Refer to REFRIGERANT CIRCUIT . and the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
-- Open the electrically activated valves, which to now open without power using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
All Vehicles
-- Switch on the A/C Service Station and the related service/repair/system information according to specification. Refer to A/C Service Station's service/repair/system information.
-- Remove the closure caps from the refrigerant circuit service connections (vehicle-specific refrigerant circuit). Refer to REFRIGERANT CIRCUIT .
-- Connect the quick-release couplings to the refrigerant circuit service connections. Refer to A/C SERVICE STATION ON REFRIGERANT CIRCUIT, CONNECTING .
-- Evacuate the refrigerant circuit using the A/C Service Station. Refer to REFRIGERANT CIRCUIT, EVACUATING .
-- Adjust the specified refrigerant oil quantity and if necessary the specified quantity of refrigerant oil and the quantity of the UV additive for leak detection on the A/C Service Station. Refer to A/C Service Station's service/repair/system information and TECHNICAL DATA .
-- Adjust on the A/C Service Station that the refrigerant will be filled on the high pressure side. Refer to the A/C Service Station's service/repair/system information.
When charging the refrigerant circuit via the low pressure side, liquid refrigerant can get into the compression chamber of the A/C compressor.
-- If it is necessary to fill the refrigerant circuit via the low pressure side, turn the A/C compressor after filling before the first activation 10 turns by hand (if necessary for example remove the input shaft to do so).
The refrigerant and the refrigerant oil are filled via the high pressure side in the refrigerant circuit.
If on a vehicle no service connection is present on the high pressure side of the refrigerant circuit, the refrigerant may be filled via a service connection om the low pressure side. To do this pay attention to the adjustment and the A/C Service Station's service/repair/system information.
If on the A/C Service Station the filling direction cannot be set if necessary remove (close) the hand wheel on the quick-release coupling connection on the low pressure side.
-- Fill the refrigerant circuit with the specified refrigerant quantity if necessary fill the specified quantity refrigerant oil and the quantity of the UV additive.
-- Switch on the A/C system after filling. Refer to WORKING WITH A/C SERVICE STATION or REFRIGERANT CIRCUIT and A/C SYSTEM, OPERATING AFTER CHARGING .
Operating an A/C System with an Electrically Driven A/C Compressor
-- Activate the A/C compressor via the "Basic Setting, Compressor Cut-In" function from Guided Fault Finding using the Vehicle Diagnostic Tester.
Additionally on vehicles with electric operated valves in the refrigerant circuit, which cannot be opened without power:
-- Via the Vehicle Diagnostic Tester the electrically activated valves which do not open without power for the operation of the A/C system enable the activation of these valves via the respective control module (to open or close) using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
On vehicles with high-voltage system and additional functions of the A/C system ("heat pump operation" or "cooling the high-voltage battery") valves may be installed in the refrigerant circuit which cannot be opened without power. These valves are opened and closed for example via a step motor and after switching off the ignition are no longer activated. To completely drain, correctly discharge and charge the refrigerant circuit no areas may be closed, for this reason the valves must be opened before these procedures. After finishing work on the activation of these valves are enabled via the respective control module. Refer to REFRIGERANT CIRCUIT and the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
All Vehicles
Should a function test be performed after charging the refrigerant circuit?
-- Check the pressures in refrigerant circuit. Refer to PRESSURES, CHECKING .
Should a function test not be performed after charging the refrigerant circuit?
-- Disconnect and the A/C Service Station from the refrigerant circuit and turn it off. Refer to A/C SERVICE STATION, SWITCHING OFF AND DISCONNECTING FROM REFRIGERANT CIRCUIT .