BMW X3 Service & Repair Manual: Note for handling r134a refrigerant

Work on the refrigerant circuit may only be carried out by experts! Avoid all contact with liquid or gaseous R134a. Wear safety goggles and gloves when working on the refrigerant circuit.

• FOLLOW SAFETY INFORMATION FOR HANDLING R134A REFRIGERANT.

WARNING: Although R134a at normal temperature is non-toxic, not inflammable and not explosive in air in any mixture ratio, it is still essential to follow various safety precautions.

As a gas, R134a 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. 45 ºC). Also avoid exposing them to mechanical stress (e.g. by dropping).

Do not weld or solder on to filled heating and air conditioning systems or in rooms into which R134a may have escaped. Exposure to flames or high temperatures (≥ 50 ºC) 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.

R134a must be drawn off, cleaned and returned to the heating and air conditioning 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.

R134a absorbs very small amounts of moisture. 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.