Suction, evacuating and filling air conditioning (R134a)
Refrigerant circuit is under high!
- If the protective caps on the filling valves are difficult to open, there is a injury hazard from leaking valve inserts.
Repair work may only be carried out on a depressurized refrigerant circuit!
- Before conducting repairs, check the actual pressure drop on the pressure gauge of the A/C service station.
Avoid contact with refrigerant and refrigerant oil.
- Follow SAFETY INSTRUCTIONS for handling tetrafluorethane refrigerant R134a.
- Follow SAFETY INSTRUCTIONS for handling refrigerant oil.
This is replaced by a direction connection on the expansion valve.
Changeover time frame:
- From 07/09 - N54
- From 08/09 - N43
- Until end of 2009 - all other engine versions except N45/N46 and S65
Shown on N54 engine by way of example.
Direct connection of filling adapter (1) on the expansion valve is shown.
Temperature sensor
Make sure filling hose (1) is laid without kinks.
Only BMW-approved R134a refrigerant may be used.
Restart engine only when the air conditioning system has been correctly filled.
Carefully shift the climate service station!
Comply with the operating instructions and service interval for the A/C service station!
Make sure that the hoses of the A/C service station are drained after the suction or filling procedure!
The climate service station contains highly sensitive components, such as scales. These components will be damaged due to improper handling, such as fast driving over a bump. This will result in a significant reduction of the measuring accuracy when suction and filling.
Filling a raised vehicle will result in minimum filling levels.
Temperature sensor
In case of complaints, carry out a heating and air conditioning performance test!
If the system fails the test, draw off, evacuate and fill the heating and air conditioning system in accordance with the operating instructions of the relevant service station.
Service interval of service station must be adhered to.
If necessary, to connect service station, use manufacturer's adapter for high-pressure connection (red).
Instructions for suctioning heating and air conditioning system:
To help separation of refrigerant and refrigerant oil, run engine at low speed (800-1200 RPM) and with heating and air conditioning system turned on for a few minutes.
The limits the entrainment of refrigerant oil while it is drawn off.
Drawn-off refrigerant oil must be changed and reintroduced via the service station.
During suction, set the blower of the heating and air-conditioning unit to the middle blower speed. This ensures that suction is more effective since the pressure on the low pressure side increases.
Recycling:
Dispose of drawn-off refrigerant oil as hazardous waste.
Observe country-specific waste disposal regulations.
Vehicle must be evacuated from both sides!
Instructions for evacuating heating and air conditioning system:
Before each filling, evacuate the refrigerant system.
Observe a suction time of at least 30 minutes.
The suction process removes all traces of ambient air, water vapor and any other gases present from the heating and air conditioning system. This enables subsequent system filling with refrigerant.
If the vacuum does not remain stable when the system is off, run the procedure for leaks in the refrigerant circuit.
During suction process, set the blower of the heating and air-conditioning unit to the middle blower speed. This ensures that suction process is more effective since the pressure on the low pressure side increases.
Instructions for filling heating and air conditioning system:
Before filling with refrigerant, replace the refrigerant oil entrained during suction.
Also top up any lost fluid as shown in the table:
Loss of R134a refrigerant
TABLE 1 indicates the permitted loss of refrigerant after a specific period of time. There is no leak. Refrigerant oil must not be topped up.
TABLE 2 indicates the how much coolant oil level must be topped up due to a loss of refrigerant because of a leak after a specific period of time.
Different cases:
- Loss of refrigerant per TABLE 1 is not exceeded
- Top up lost R134a refrigerant
- It is not permitted to top up the refrigerant oil
- Loss of refrigerant per TABLE 1 is exceeded
- Top up lost R134a refrigerant
- refrigerant oil must be topped up additionally per TABLE 2 .
| Number of years since last filling | 0 to 1 | 1 to 2 | 2 to 3 | 3 to 4 | 4 to 5 |
| Permissible loss [g] --> Do not top up refrigerant oil | ≤ 30 | ≤ 60 | ≤ 90 | ≤ 120 | ≤ 150 |
| Number of years since last filling | R134a loss of coolant [g] | Top up quantity refrigerant oil |
|---|---|---|
| 0 to 1 | < 120 | 0 |
| 120 - 150 | 10 | |
| > 150 | 20 | |
| 1 to 2 | < 180 | 0 |
| 180 - 210 | 10 | |
| > 210 | 20 | |
| 2 to 3 | < 240 | 0 |
| 240 - 270 | 10 | |
| > 270 | 20 | |
| 3 to 4 | < 300 | 0 |
| 300 - 330 | 10 | |
| > 330 | 20 | |
| 4 to 5 | < 360 | 10 |
| > 360 | 20 |
Follow notes for opening and part replacement in refrigerant circuit.
Depending on the type of component replaced on the heating and air conditioning system, it may be necessary to the top up the refrigerant oil, even if no measurable losses have occurred during suctioning. Follow the notes provided by the heating and air conditioning system manufacturer, taking into account the tolerances and inaccuracies shown in the operating instructions of the relevant service station.
Information on the required refrigerant fill quantity for the entire heating and air conditioning system is contained on the nameplate (1) in the engine compartment.
If necessary, refer to the Technical Data for CAPACITY .
Installation note:
Reseal refrigerant filler necks on vehicle with sealing caps.