Chapter 9- Refrigerants
6. When the pressure reaches 5 to 10 psig, open the OIL DRAIN
valve, collect oil in an appropriate container, and dispose of
container as indicated by local, state, or Federal Regulation.
ABSORBED DURING ITS PREVIOUS USE.
Performing the Recovery Cycle
You are now ready to recover. Follow these steps:
1. Be sure the equipment you are using is designated for the
refrigerant you intend to recover.
2. Record the sight glass oil level. Having drained it, it should be
zero.
3. Check the cylinder refrigerant level before beginning recovery
to make sure you have enough capacity.
4. Confirm that all shut-off valves are closed before connecting
to the AC system.
5. Attach the appropriate hoses to the system being recovered.
6. Start the recovery process by operating the equipment as per
the manufacturer's instructions.
7. Continue extraction until a vacuum exists in the AC system.
8. If an abnormal amount of time elapses after the system
reaches 0 psig and does not drop steadily into the vacuum
range, close the manifold valves and check the system pres-
sure. If it rises to 0 psig and stops, there is a major leak. Refer
to Chapter 8 for troubleshooting leak procedures.
9. Check the system pressure after the recovery equipment
stops. After five minutes, system pressure should not rise
above "0" gauge pressure. If the pressure continues to rise,
restart and begin the recovery sequence again. This cycle
should continue until the system is void of refrigerant.
10. Check the sight glass oil level to determine the amount of oil
that needs to be replaced.
11. Mark the cylinder with a RECOVERED (red) magnetic label
to reduce the chance of charging a system with contaminated
refrigerant. Keep a record of the amount of refrigerant recov-
ered, if you have the capability.
Check the sight glass oil level to determine the amount
lost during recovery. You must add this amount of oil
back into the system.
Performing the Recycling Procedure
The recovered refrigerant contained in the cylinder must undergo the
recycle procedure before it can be reused. The recycle or clean mode is a
continuous loop design and cleans the refrigerant rapidly. Follow equip-
ment manufacturer's instructions for this procedure.
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