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WARNING
• WEAR GOGGLES!!
• AVOID CONTACT WITH REFRIGERANT
PREPARING THE SIGHT GLASS
When Using Vacuum from a Recycling Machine
1. Connect both the red and the blue hoses supplied to the corresponding end of the sight glass.
2. Connect both the red and blue coupler to the corresponding end of the hose. Close each coupler by turning the knob
counterclockwise (manual couplers only.) Connect the blue low side hose and coupler from your RRR machine to the
low side fitting on the blue side of the sight glass.
3. Open both ball valves on each side of the sight glass.
4. Run a vacuum for 3 minutes from the control panel on your RRR machine. This will remove any atmosphere from the
sight glass to allow for an accurate test.
5. Disconnect the low side RRR machine coupler from the sight glass when vacuum run time is completed.
6. Go to using the sight glass section.
When Using Vacuum from a Vacuum Pump
1. Close both ball valves. Connect the red hose supplied to the red side of the sight glass. Attach the high side coupler
to the hose and close the coupler by turning the knob counterclockwise (manual couplers only.)
2. Connect the low side coupler to the blue hose and close the coupler by turning the knob counterclockwise (manual
couplers only.)
3. Connect the low side coupler to the service port on the sight glass. Open the coupler by turning the knob clockwise
(manual couplers only.)
4. Connect the other end of the blue hose to your vacuum pump.
5. Open the red high side ball valve, leave the blue low side ball valve closed.
6. Run your vacuum pump for 3 minutes. This will remove any atmosphere from the sight glass to allow for an accurate
test.
7. Disconnect the blue hose from the vacuum pump when vacuum time is completed. Close the low side coupler by
turning the knob counterclockwise (manual couplers only.) Disconnect the blue coupler from the sight glass. The
fittings on the blue hose and coupler both have auto shutoff’s which will maintain the vacuum created in the sight
glass and hoses.
8. Connect the blue hose to the blue side of the sight glass.
USING THE SIGHT GLASS
1. Close both ball valves on the sight glass.
2. Connect the red coupler to the high side of the AC system. Open the coupler by turning the knob clockwise (manual
couplers only.)
3. Connect the blue coupler to the low side of the AC system. Open the coupler by turning the knob clockwise (manual
couplers only.)
4. Start the vehicle and turn the AC system on.
5. Hold the sight glass in a vertical position with the red hose down.
6. SLOWLY open the red side ball valve.
7. When the sight glass is ¼ full of liquid refrigerant, close the red side ball valve (be sure the blue side ball valve is still
closed as well).
8. Allow the refrigerant to stabilize.
9. Check the color of the refrigerant using the chart below. Check for any debris in the refrigerant.
CLEARING THE SIGHT GLASS OF REFRIGERANT
1. To put the refrigerant back into the AC system, first turn off the AC system and vehicle.
2. Close the high side coupler by turning the knob counterclockwise (manual couplers only.) Remove the red coupler
from the high side of the vehicle.
