BMW 7 Series: Instructions For Handling R 134a Refrigerant

Work on the refrigerant circuit may only be carried out by experts!

Avoid all contact with liquid or gaseous R 134a. Wear safety goggles and gloves when working on the refrigerant circuit.

• Follow SAFETY INSTRUCTIONS for handling R134a refrigerant.

WARNING: Although R 134a at normal temperature is non-toxic, non-flammable and not explosive in air in any mixture ratio, it is still essential to follow various safety precautions.

As a gas, R 134a is colorless, odorless and heavier than air. If it enters the atmosphere, this may result in an imperceptible danger of asphyxiation or in cardiac palpitations, especially in workshop pits. Ventilate rooms adequately; if necessary, turn on installed extractor systems.

Store charged refrigerant pressure flasks in a place where they are not exposed to direct sunlight or any other heat source (max. 45ºC). Also avoid exposing them to mechanical stress (e.g. by dropping).

Do not weld or solder on to filled A/C systems or in rooms into which R 134a may have leaked. Exposure to flames or high temperatures (> or = 50ºC) may give rise to toxic decomposition products (fluorine gas). For this reason, do not smoke either.

In the event of fire, carbon dioxide (CO2), extinguishing powder and a sprayed water jet are deemed to be suitable extinguishant. Cool reservoirs at risk with a sprayed water jet (risk of bursting!).

If the protective caps on the filling valves are difficult to open, there is a risk of injury from leaking valve inserts (high pressure).

The filled refrigerant circuit of the A/C system is subject to excess pressure. Before carrying out repairs on the A/C system, it is absolutely essential to draw off the refrigerant.

• Before conducting repairs, check the actual pressure drop on the pressure gauge of the A/C service station.

R 134a must be drawn off, cleaned and returned to the A/C system using an A/C service station following the relevant operating instructions.

For a properly functioning A/C system, it is essential to have the greatest possible levels of cleanliness when working on the A/C system and the longest possible evacuation (at least 30 minutes dehumidification from refrigerant circuit) before each filling of the A/C system.

R 134a absorbs moisture very easily. Therefore, seal off opened pipes, condenser, evaporator, compressor and dryer flask immediately with plugs.

• If an A/C system has been completely drained by leakage, accident or repair, the DESICCANT INSERT must be replaced as excessive moisture may have entered the system.

With exchange parts, the plugs may only be removed immediately before the lines are connected. In the event of warranty claims, the used parts must be provided with plugs to be able to determine the cause of the damage.

Installation note

After each refill of an A/C system, check that the protective caps of the filler valves are hand-tight. They serve as additional seals.

INSTRUCTIONS FOR OPENING AND REPLACING PARTS IN REFRIGERANT CIRCUIT

WARNING:

• Avoid contact with refrigerant and refrigerant fluid
• Follow safety information for handling R134A refrigerant.
• Follow safety information for HANDLING REFRIGERANT FLUID

IMPORTANT:

• Always use new O-rings each time A/C connections are opened (refer to Electronic Parts Catalogue) They must not be coated.

  Use special tool 00 9 030 to install sealing rings without damaging them.

• Open the refrigerant circuit for as short of a period as possible.
• Close all components and lines in the refrigerant circuit and return parts immediately following the removals at openings with special tool 32 1 270 to prevent penetration of moisture or foreign objects.
• If the refrigerant circuit was closed at the openings with special tool 32 1 270 but it remains open for more than 24 hours, the dryer insert for the air conditioning must be replaced.

I. Part replacement as preliminary work fur further repair work and part replacement based on gradual leakage

(minor leak, e.g. hairline crack)

Procedure:

• DRAW OFF A/C system, then determine drawn-off refrigerant oil quantity
• Carry out part replacement
• Replace removed refrigerant fluid and additionally top up with new refrigerant fluid according to components replaced:
  • Compressor: refer to NOTES ON REPLACING COMPRESSOR
  • Evaporator: 10 ml
  • Capacitor: 20 ml
  • Desiccant insert/dryer flask: 20 ml
  • Each replaced refrigerant line: 10 ml
  • Capacitor with integrated dryer: 40 ml
  • Safety pressure switch and seals: no additional refrigerant fluid
• EVACUATE AND FILL A/C system

II. Part replacement due to sudden leak

(major leak, e.g. pipe break due to accident)

Procedure:

• DRAW OFF A/C system, then determine drawn-off refrigerant oil quantity
• Carry out part replacement
• Replace removed refrigerant fluid and additionally top up with new refrigerant fluid according to components replaced:
  • Compressor: refer to NOTES ON REPLACING COMPRESSOR
  • Evaporator: 35 ml
  • Capacitor: 35 ml
  • Desiccant insert/dryer flask: 55 ml
  • Each replaced refrigerant line: 35 ml
  • Capacitor with integrated dryer: 55 ml
  • Safety pressure switch and seals: no additional refrigerant fluid
• EVACUATE AND FILL A/C system

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