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J 39500-B GM Air Conditioning Refrigerant Recovery, Recycling and Recharging System

Notice: R-12 refrigerant and R-134a refrigerant must never be mixed, even in the smallest of amounts, as they are incompatible with each other. If the refrigerants are mixed, compressor failure is likely to occur. Refer to the manufacturer instructions included with the service equipment before servicing.

All with one hook-up, the J 39500-B GM air conditioning refrigerant recovery, recycling and recharging (ACR4) system removes Refrigerant-134a from the vehicle air conditioning (A/C) system, recycles, and recharges the system. Single pass filtering during the recovery cycle, plus automatic multiple pass filtering during the evacuation cycle assures a constant supply of clean and dry refrigerant for A/C system charging. Refer to the manufacturer's instructions for further information.

Recovering the Refrigerant

  1. Connect a battery charger in order to prevent battery drain.

  2. Object Number: 300810  Size: SH

    Important: Use only the 23 kg (50 lb) unit refrigerant tank (J 39500-50) designed for the ACR4. The calibration of the unit overfill limitation mechanism is specific for use with this tank. The tank valving is specific for use with the unit.

  3. Attach the red high-side hose with the quick disconnect coupler to the high-side refrigerant service valve fitting of the vehicle A/C system.
  4. This valve is in the receiver dehydrator tube, between the receiver and dehydrator and the condenser (2).

  5. Open the high-side coupler valve.
  6. Attach the blue low-side hose with the quick disconnect coupler to the low-side refrigerant charge valve fitting of the vehicle A/C system.
  7. This valve is located between in the compressor and condenser hose, between the compressor and the expansion (orifice) tube.

  8. Open the low-side coupler valve.
  9. Important: If the A/C system has no refrigerant, do not continue with the recovery operation. A recovery operation without refrigerant draws air into the recovery tank.

  10. Observe the high-side gauge and the low-side gauge on the unit control panel in order to be sure the A/C system has pressure.
  11. No pressure indicates that the system has no refrigerant in need of recovery.

  12. Open both the high-side and the low-side valves on the control panel.
  13. Open both the red LIQUID and the blue GAS valves on the tank.
  14. Slowly open the oil drain valve in order to determine whether the oil separator contains oil.
  15. Drain any oil present in the separator into the catch bottle at the bottom of the unit.
  16. Close the oil drain valve.
  17. Dispose of the oil in the catch bottle in an appropriate manner.
  18. Return the bottle in place on the unit.

  19. Plug the unit into the proper voltage outlet.
  20. Activate the MAIN POWER switch.
  21. Start the engine.
  22. With the A/C system in the ON position in order to stabilize the system, idle the engine for a period of one minute.
  23. Turn the ignition switch to the OFF position.
  24. Connect a battery charger in order to prevent battery drain.
  25. Turn the ignition switch to the RUN position.
  26. Important: The blower motor in the HIGH setting increases the rate at which the J 39500-B recovers refrigerant. Maintain the A/C blower motor on the HIGH setting during the recovery operation.

  27. Turn the blower motor switch to the HIGH position.
  28. Press the RECOVER key on the keypad.
  29. Observe the cleaning process, which is 30-180 seconds in duration.
  30. The unit clears itself of refrigerant.

    The display reads CL-L.

  31. When the cleaning is complete, the unit automatically starts the recover.
  32. The control panel shows that the unit is in the RECOVER mode of the AUTOMATIC cycle.

  33. The compressor automatically ceases operation when the initial recovery occurs at a vacuum of approximately 57 kPa (17 in of Hg).
  34. Important: 

       • The recovery might remove a small amount of the A/C system lubricating oil polyakylene glycol (PAG) with the refrigerant. Often, the recovery does not remove any oil. The amount of oil removed varies greatly. The amount of oil removed depends on various conditions of the vehicle. The J 39500-B separates the oil from the refrigerant.
       • The flashing of the OIL/OZ (OIL/GMS) indicator is a reminder: drain the recovered oil at this time. Replace the same amount of oil into the A/C system when you recharge with refrigerant the system.

  35. At the end of the initial recovery process, the display shows CPL.
  36. The display then alternately displays the weight of the refrigerant recovered and the OIL/OZ (OIL/GMS) indicator.

  37. Slowly open the oil drain valve in order to drain the oil into the calibrated oil catch bottle at the bottom of the unit.
  38. Close the oil drain valve.
  39. Record the amount of oil in the catch bottle.
  40. Dispose of the recovered oil in an appropriate manner.
  41. Never reuse this oil.

  42. Observe the LOW-SIDE GAGE reading on the control panel.
  43. • If the A/C system maintains a vacuum, the recovery is complete.
    • A rise in the LOW-SIDE GAGE pressure above 0 indicates the presence of more refrigerant.

    Important: 

       • If the display flashes the FULL indicator during the recovery process, the unit ceases operation. The unit tank is full.
       • Prior to continuation of the recovery process, install an empty unit tank (J 39500-50) in order to accommodate additional refrigerant. Do not use any other kind of tank.
       • If necessary, lower the amount of refrigerant in the unit tank by charging other vehicles.

  44. If refrigerant remains in the system, press the HOLD/CONT key on the keypad in order to recover the additional refrigerant.
  45. Repeat the previous step, as necessary, until the system maintains a vacuum for 2 minutes.

Evacuation

  1. Ensure that the unit tank has sufficient R-134a refrigerant for charging.
  2. Simultaneously press the RESET key and the ENTER key in order to enter the diagnostic mode.
  3. Press the 6 key.
  4. The display must show 16 kg (36 lb) or more.

  5. If the display shows less than 16 kg (36 lb), add new refrigerant to the tank.
  6. With the high-side hose and the low-side hose connected to the vehicle, open the red high-side valve and blue low-side valve on the control panel.
  7. Important: 

       • In order to remove all of the air and in order to properly dry the A/C system, the unit automatically enters a preprogrammed evacuation period.
       • In order to increase the evacuation period, press the keys in order to enter the time desired. The new entry shows on the display. Press the ENTER key. The display blinks in order to indicate the input of the data.

  8. Open both the red LIQUID valve and blue GAS vapor valve on the tank.
  9. Important: 

       • Automatic refrigerant recycling during each evacuation is a feature of the J 39500-B . The process requires no action of the technician.
       • The control panel MOISTURE indicator is green during the recycling. This verifies that the refrigerant moisture content is within the specifications. A yellow MOISTURE indicator indicates a set condition requiring a filter/drier cartridge change. Refer to the manufacturer instructions.
       • The J 39500-B automatically vents noncondensable gases, mostly air, during the recycling process. A sound of pressure release is audible as this happens. This is a normal function.

  10. Press the VACUUM key in order to start the vacuum pump.
  11. Observe the following process:

    7.1. The display counts down the vacuum time in order to indicate the operation time remaining.
    7.2. The display reads RECYCLE 5 seconds after the pump starts.

    RECYCLE appears while the process takes place.

  12. At approximately the 12-minute mark on the display, after a 3-minute period of pump operation, press the HOLD/CONT key in order to stop the vacuum pump.
  13. 8.1. A reading of 0 vacuum indicates a major system leak.

    Repair the leak.

    Restart the evacuation procedure.

    8.2. If the display indicates a vacuum of 91-101 kPa (27-20 in of Hg), close the low-side valve and the high-side valve.
    8.3. For a few minutes, observe the vacuum level as a leak check of the A/C system.

    If the vacuum does not remain, find and repair the leak prior to continuation of the evacuation.

    8.4. If the vacuum maintains a level of 91-101 kPa (27-30 in of Hg), open the high-side valve and the low-side valve.
    8.5. Press the HOLD/CONT key in order to restart the vacuum pump.

    Important: 

       • Frequently change the vacuum pump oil.
       • When the pump has run for a total time of 10 hours, the OIL message flashes on the control panel display as a reminder to change the oil.
       • If the OIL warning flashes during the operation, press the CONT key. Change the oil prior to the next operation.

  14. When the vacuum sequence completes the programmed time period, the display shows CPL in order to indicate that the evacuation is complete.

Charging the A/C System (Engine Off)

Important: 

   • You MUST evacuate the A/C system prior to charging the system.
   • Verify that the LB/KG switch on the back of the unit is set for the desired units of weight.
        Operate the switch with the main power OFF.

  1. Close the low-side valve on the control panel.
  2. Open the high-side valve on the control panel.
  3. Press CHG on the keyboard in order to be sure that the unit is in the program mode.
  4. Enter the amount of refrigerant charge to charge the A/C system by pressing the appropriate number keys.
  5. Use the correct unit of weight (pounds or kg).

  6. Press ENTER.
  7. A blink on the display indicates the charge amount is in the unit memory.

    Important: 

       • Charge the A/C system with amounts of R-134a specified.
            Do not overcharge.
       • Charge the A/C system (all) with 0.91 kg (2.0 lb).

  8. Press CHG on the keyboard in order to begin the charging process.
  9. The display shows AUTOMATIC and the amount of refrigerant programmed for charging.
  10. • The display counts down to zero as the charging process proceeds.
    • At the end of the process, the display show CPL.

Successful Transfer Complete

Important: If the transfer of refrigerant stops before complete, refer to Unsuccessful Transfer.

  1. Close the high-side valve on the unit control panel. Both valves should now be closed.
  2. Start the engine. Turn ON the A/C system and let the system run until the readings on the high-side and low-side gauges stabilize.
  3. Compare the readings, the outlet temperatures, the ambient temperature, and the humidity to the A/C performance table. Refer to System Performance Test .

  4. With the A/C system running, close the high-side coupler valve.
  5. Disconnect the high-side (red) hose from the vehicle.

  6. Open the high-side and the low-side valves on the control panel.
  7. Refrigerant from both hoses will be drawn quickly into the A/C system through the low-side (blue) hose.
  8. Close the low-side coupler valve and disconnect the valve from the vehicle.

Unsuccessful Transfer

On rare occasions, the total charge does not transfer to the vehicle A/C system. This can occur for the following reasons:

  1. If the transfer is too slow because the pressure in the tank unit and the vehicle A/C system are about the same, the unit emits an audible signal, and the display shows the weight remaining for transfer. When this happens, do the following steps:
  2. 1.1. Close the high-side valve.
    1.2. Open the low-side valve.
    1.3. Start the vehicle A/C system. Press HOLD/CONT on the keyboard. This will put the remainder of the charge in the A/C system.
    1.4. Continue with the Successful Transfer Complete procedure above.
  3. If the transfer will not complete and the display shows CHECK REFRIGERANT, there is not enough refrigerant in the tank to complete the process. This condition requires the recovery of the partial charge of refrigerant in the vehicle A/C system, and another complete evacuation and charge procedure.
  4. 2.1. Press HOLD/CONT on the keyboard in order to interrupt the cycle.
    2.2. Press RESET in order to reset this unit.
    2.3. Recover the refrigerant that has been charged into the system.
  5. Following the manufacturers instructions, add refrigerant to the tank and refer to Evacuation.