Draining and Filling of Refrigerant

WARNING:
^ Use protective gloves and goggles when working with refrigerants. Frostbite could occur if skin or eyes come into contact with the refrigerant.

^ Only fill refrigerant from a 725 gram refrigerant bottle to the low-pressure side of the A/C system. If the bottle is connected to the high-pressure side, there is a risk that it might explode when the car engine is started.

CAUTION:
^ Under no circumstances whatsoever must the draining and filling equipment for R134a refrigerant be used for R12 refrigerant, and vice versa.

^ Only small amounts of the wrong refrigerant or the wrong compressor oil will give rise to chemical reactions which in the long run will ruin both the equipment and the car's A/C system.

^ Make sure that the amount of compressor oil in the A/C system is correct before starting vacuum pumping and filling. Refer to "Compressor Oil - Filling and Adjustments". Service and Repair

NOTE:
^ Draining of the system should be carried out on both the low-pressure and high-pressure sides simultaneously. A non-return valve in the inlet of the compressors low-pressure side makes draining of only one side impossible.

^ Vacuum pumping should be carried out on both the low-pressure side and high-pressure sides simultaneously. A non-return valve in the inlet on the compressor's low-pressure side makes vacuum pumping on only one side impossible.

DRAINING AND FILLING OF REFRIGERANT
The use of special equipment for draining and filling is described bellow. This equipment has been developed for handling R134a refrigerant. For information about the equipment, consult the manufacturer's manuals. Remember to drain compressor oil from the draining stations at regular intervals (after every fourth draining is about right).





Components
1 Robinair 10324 Smart Cart (vacuum pumping and tilling)
2 Robinair 17234 (draining)
3 Robinair 17644 (draining)
4 Robinair 10094 (vacuum pumping)
5 725 gramme refrigerant bottle (filling)






Snap-on Couplings
Special snap-on couplings have been designed to connect the hoses of the draining and filling equipment to the A/C system. These snap-on couplings are of Schrader valve type and connection is therefore carried out in two stages:
1. Press the snap-on coupling onto the service connection.
2. Turn the knob clockwise to open the valve and let the refrigerant pass through the connection.

To remove the snap-on coupling, first turn the knob (2) anti-clockwise to close the valve. Then remove the snap-on coupling by pressing the spring-loaded catch (3), so that the locking sleeve (4) can be pulled up.

When the catch is pressed in, you will hear a hiss as the catch also serves to evacuate any refrigerant that is trapped in the snap-on coupling.

The connections on the low-pressure and high-pressure sides are different to eliminate the risk of confusion.





Measuring Pressure With The Robinair 10324 Smart Cart
1. Check that the cock on the blue low-pressure hose and the cock on the red high-pressure hose on the pressure gauge stand are both closed.
2. Using a snap-on coupling, connect the blue low-pressure hose to the low-pressure side of the A/C system.
3. Using a snap-on coupling, connect the red high-pressure hose to the high-pressure side of the A/C system.
4. Open the valves on both snap-on couplings by screwing in the knobs.
5. Start the engine. At an engine speed of 1500-2000 rpm and an air temperature of 20 °C you should be able to read the following pressures on the pressure gauge stand when the compressor is working:
- Low-pressure side: 1-3 bar.
- High-pressure side: 12-16.5 bar.





Robinair 10324 Smart Cart And Robinair 17234 Draining Station - Draining
1. Using a snap-on coupling, connect the blue low-pressure hose to the low-pressure side of the A/C system.
2. Using a snap-on coupling, connect the red high-pressure hose to the high-pressure side of the A/C system.
3. Open the valves on both snap-on couplings by screwing in the knobs.
4. Using the yellow hose, connect the pressure gauge stand's middle outlet to the draining station.
5. Open the cocks on the blue low-pressure hose and the red high-pressure hose and the cock on the yellow hose connected to the pressure gauge stand's middle outlet.
6. Open the blue cock ("liquid") for liquid refrigerant and the red cock ("Gas") for gaseous refrigerant on the draining station's container.
7. Start the draining station. When draining is finished, the draining station will switch OFF automatically.
8. Close the cocks on the blue low-pressure hose, the red high-pressure hose and the yellow hose connected to the pressure gauge stand's middle outlet.
9. Remove the yellow hose from the draining station. Draining is now finished and work on the A/C unit can commence.





Robinair 10324 Smart Cart And Robinair 17234 Draining Station - Vacuum Pumping And Filling Of Refrigerant
1. Using a snap-on coupling, connect the blue low-pressure hose to the low-pressure side of the A/C system.
2. Using a snap-on coupling, connect the red high-pressure hose to the high-pressure side of the A/C system.
3. Open the valves on both snap-on couplings by screwing in the knobs.
4. Open the cocks on the blue low-pressure hose and red high-pressure hose on the pressure gauge stand.
5. Open the blue cock ("Liquid") for liquid refrigerant on the container on the Smart Cart.
6. Check that the cock on the yellow hose on the pressure gauge stand's middle outlet is closed.





7. Program vacuum pumping for 30 minutes by pressing "30" on the control panel in the "Vacuum minutes" position. Acknowledge the selection by pressing "ENTER".
8. Press "REV. PROG".
9. Press "0.73" to specify the number of kilograms of refrigerant to be filled. Acknowledge the selection by pressing "ENTER".
10. Press "REV. PROG".
11. Press "START" to start vacuum pumping.
12. Move the A/C hoses slightly and make sure that there are no leaks in the system. The pressure must not increase by more than 10 mbar in 5 minutes.





13. Press "START" to start filling of refrigerant.
14. Stop the filling process by pressing "HOLD" when about 200 grammes of refrigerant has been filled.
15. Move the A/C hoses slightly and check with a leakage detector designed for R134a that the system does not leak.
16. Continue the filling process by pressing "START". When filling is finished, "CPL" appears in the display on the control panel.
17. Close the cocks on the blue low-pressure hose and red high-pressure hose on the pressure gauge stand.
18. Start the car and wait until the compressor starts to work. Rev up the engine so that the pump vanes in the compressor's rotor are flung outwards. The pressure on the low-pressure side should be 1.5-3.0 bar.
19. Close the valves on the snap-on couplings on the A/C system's service connections by turning the knobs anticlockwise.
20 Remove the snap-on couplings and refit the protective plugs in the service valves.





Robinair 17644 Draining Equipment And Robinair 10094 Vacuum Pump - Draining
1. Open the red cock ("Gas") for gaseous refrigerant on the draining station's container.
2. Connect the yellow hose on the pressure gauge stand's middle outlet to the inlet side of the draining station.
3. Using a snap-on coupling, connect the blue low-pressure hose to the low-pressure side of the A/C system.
4. Using a snap-on coupling, connect the red high-pressure hose to the high-pressure side of the A/C system.
5. Open the valves on both snap-on couplings by screwing in the knobs.





6. Open the cocks on the blue low-pressure hose and red high-pressure hose on the pressure-gauge stand.
7. Start the draining station.
8. If the draining station operates correctly, it should show negative pressure when the draining valve is closed.
9 Open the draining valve and drain the A/C system of refrigerant.
10. Close the draining valve when the gauge on the draining station shows negative pressure (about 10 inch Hg).
11. Turn off the draining station.
12. Close the cocks on the blue low-pressure hose and red high-pressure hose on the pressure gauge stand.
13. Remove the yellow hose from the draining station. Draining is now finished and work on the A/C system can commence.





Robinair 17644 Draining Equipment And Robinair 10094 Vacuum Pump - Vacuum Pumping
1. Using a snap-on coupling, connect the blue low-pressure hose to the low-pressure side of the A/C system.
2. Using a snap-on coupling, connect the red high-pressure hose to the high-pressure side of the A/C system.
3. Open the valves on both snap-on couplings by screwing in the knobs.
4. Connect the yellow hose on the pressure-gauge stand's middle outlet to the refrigerant flask.
5. Open the cocks on the blue low-pressure hose and red high-pressure hose on the pressure-gauge stand.
6. Start the vacuum pump
7. Open the vacuum valve and let the pump run for 30 minutes.
8. Close the vacuum valve when vacuum pumping is finished after about 30 minutes. The pressure should then be 0-10 mbar.
9. Switch OFF the pump.
10. Move the A/C hoses slightly and make sure that there are no leaks in the system. The pressure must not increase by more than 10 mbar in five minutes.





Robinair 17644 Draining Equipment And Robinair 10094 Vacuum Pump - Filling Of R134a Refrigerant From A 725 Gramme Refrigerant Flask
1. Close the cocks on the blue low-pressure hose and red high-pressure hose on the pressure gauge stand.
2. Close the valve in the snap-on coupling on the red high-pressure hose on the high-pressure side of the A/C system by turning the knob anticlockwise.
3. Then remove the red high-pressure hose's snap-on coupling and refit the protective plug in the connection.





4. Place the flask with refrigerant upside down and open the cock on the flask.

NOTE: The flask with refrigerant must be stood upside down as otherwise it is not possible to empty it completely.

5. Fill with 200 grammes of refrigerant by carefully opening the cock on the blue low-pressure hose on the pressure gauge stand for about 10 seconds. 200 grammes of refrigerant corresponds to a pressure of 4-5 bar.
6. Move the A/C hoses slightly and check with a leakage detector designed for R134a that there are no leaks in the system.
7. Open the cock on the blue low-pressure hose on the pressure gauge stand and continue filling until the pressure has stabilized.
8. Close the cock on the blue low-pressure hose on the pressure gauge stand.





9. Start the engine and wait until the compressor starts to work. Rev up the engine so that the pump vanes are flung outwards (this will be noticed by the pressure dropping below 3 bar on the gauge by the blue low-pressure hose on the pressure-gauge stand).
10. Open the cock on the blue low-pressure hose on the pressure-gauge stand when the compressor starts working so that the remaining amount of refrigerant is sucked into the compressor.
11. Close the cock on the blue low-pressure hose on the pressure gauge stand when the bottle with refrigerant is empty.
12. Close the valve in the snap-on coupling on the blue low-pressure hose on the low-pressure side of the A/C system by turning the knob anticlockwise.
13. Remove the blue low-pressure hose's snap-on coupling and refit the protective plug in the service valve.
14. Close the cock on the flask with refrigerant.
15. Remove the yellow hose from the flask with refrigerant.