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Home >> Volvo >> 1997 >> 960 L6-3.0L VIN 96 B6304F2 >> Repair and Diagnosis >> Heating and Air Conditioning >> Service and Repair >> Servicing System >> R 134a System Draining and Recycling Units >> RHS 650 Refrigerant Drainage and Recycling Unit >> Draining Refrigerant From Car

Draining Refrigerant From Car

WARNING:
- Before commencing work, read and observe SAFETY PRECAUTIONS when working on A/C systems.
Technician Safety Information

- Always wear protective goggles and gloves when working with refrigerant Contact with eyes and skin may cause frostbite.

- Mixtures of R134a and compressed air must not be used for troubleshooting due to the risk of explosion at high pressures and temperatures.

CAUTION: Read General information on repair and replacement of A/C system components under A/C SYSTEM COMPONENTS. Vehicle Damage Warnings

NOTE:
- The A/C system in the car must be at least at roam temperature, approx. 2O °C (68 °F), to achieve fast drainage. In winter therefore the car should be housed overnight in the workshop before commencing work.

- The drainage time will be reduced if the A/C system has recently been in service and the engine is hot (radiation heat). If possible run the system for about 5 minutes before draining to shorten the time.

Draining Refrigerant From Car To RHS 650 Unit





1. Check gauge glass (22) to ensure that RHS 650 is not full of refrigerant but that capacity is available for at least another 1000 grammes (2.205 lb). If unit requires to be drained see DRAINAGE TO STORAGE CONTAINER (gas bottle).
Servicing System





2. Connect RHS 650 to single-phase 220 V/5O Hz grounded supply.
3. Settings:
- Valves (1), (2), (3) and (4) must be closed. Connect low-pressure hose (blue) to high-pressure circuit (14).
- Connect high-pressure hose (red) till low-pressure circuit (13). Connection (20) should be closed.
- Set selector switch (7) to TEST.
4. Check that low-pressure hose (blue) connection fitting is closed i.e. turned counterclockwise to end position.





5. Connect low-pressure hose (17) (blue) to A/C system service valve in car.

NOTE: The A/C system service valve is located on the pipe beside the diagnostic units (DLCs). This applies to cars from 1994 on.





6. Open Schraeder valve on connection fitting by turning cock clockwise (OPEN) as illustrated.





7. Draining refrigerant:
- Close main switch (11).
- Set selector switch (7) to RECOVERY (drainage).
- Open valves (1) and (2) slowly (otherwise oil may escape from system).
- Unit will drain system automatically.

NOTE: If RHS 650 unit requires to be filled with R134a from an external gas bottle, low-pressure connection (13) should be used for this purpose. This may be carried out while the A/C system in the car is being drained through the high-pressure connection.





- The quantity of refrigerant drained may be read from the gauge glass (22) on the glass storage cylinder.
- If the unit becomes full, the red warning lamp (8) will light and the compressor will stop.
- The RECOVERY lamp (9) will light, indicating that the compressor is running, as long refrigerant remains in the system. The lamp will go out and the compressor will stop automatically when the system pressure is sufficiently low.
- The low-pressure gauge (12) should now indicate a partial pressure; in other words, a value below 0 bar (atmospheric pressure), normally -0.2 to -0.4 bar (2.9 to 5.8 psi). The pressure will return to 0 bar after approx. 5 minutes and will stabilize at that value. However, if the pressure remains low, the compressor will restart. The A/C system is now drained.
- The drainage procedure from starting of the compressor until the unit stops and the pressure returns to 0 normally takes 20-25 minutes.




8. Open main switch.


NOTE: The gauge glass (22) on the glass storage cylinder does not indicate the exact quantity of refrigerant drained from the A/C system since a certain amount always collects in the drainage unit air receiver.


Topping up A/C system with PAG oil


NOTE: Topping up of the PAG (Polyalkylene Glycol) compressor oil should be carried out afier the A/C system has been drained, and before vacuum-pumping and filling with refrigerant.


NOTE: The low-pressure gauge (12) should indicate 0 bar (atmospheric pressure). If the gauge shows a partial pressure, it will not be possible to drain off oil which has been extracted with the refrigerant from the A/C system, due to the presence of air.


9. Open drain cock (18) on unit to check if oil has been extracted from A/C system.
Determine quantity of oil from gauge glass (19). Top up system with same quantity.




10. Remove:
- connection fining on blue hose from car A/C system
- Schraeder valve from A/C system service valve. Use valve tool 951 1204.





11. Top up system with necessary quantity of fresh PAG oil. Check gauge glass (19).


NOTE: Always use fresh PAG compressor oil. For 960 (with Sanden compressor) use P/N 116 1425-2. For 700/940 and 960 Turbo (with Seiko-Seiki compressor), use P/N 116 1426-0.

Use filler syringe (without plastic hose) supplied with unit. Syringe may need to be cleaned to avoid mixing different oils.




Attach pipette mounted on syringe handle to end of syringe.




12. Install Schraeder valve.
Use valve tool 951 1204.


NOTE: Use only thumb and index finger to tighten Schraeder valve with tool 951 1204-1 to prevent damage to varve seal.

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