3 Refrigerant Recovery Procedures
Learn how to prepare, connect, and operate recovery equipment for low-pressure appliances while protecting refrigerant quality and handling cylinders safely.
Understand the equipment and appliance
Low-pressure appliances, often chillers using refrigerants such as R-11 or R-123, may operate below atmospheric pressure. Recover refrigerant with equipment rated for the appliance and refrigerant, and follow the equipment and chiller manufacturers’ instructions. Section 608 technicians must use certified for applicable stationary appliances.
Prepare and connect the recovery circuit
Identify the refrigerant and charge. Check the equipment nameplate and service records. Do not mix refrigerants.
Select a . Use a cylinder approved for the refrigerant and rated for its pressure.
Prepare the chiller. Shut down and isolate the appliance as required. Follow manufacturer instructions for managing the water side: circulate or remove water during evacuation as appropriate to reduce the risk of freezing chiller tubes.
Set up the recovery circuit. Connect the chiller’s liquid and vapor service connections through suitable hoses and manifold or recovery-unit connections. Connect the recovery unit to the cylinder’s appropriate valve or valves, and place the cylinder on a scale. Check hoses, fittings, and valves for leaks. Arrange connections and valves according to the recovery-unit manual.
Limit refrigerant release. Evacuate or clear hoses using the equipment’s approved procedure; do not vent refrigerant. Match the recovery unit’s inlet and outlet connections to the intended liquid or vapor flow.
Recover liquid, then vapor
is generally the faster first step because liquid contains much more refrigerant by mass than the same volume of vapor. Use a liquid service connection and a recovery unit rated for . A may transfer bulk liquid quickly when the system layout and equipment permit it; use only the manufacturer’s specified valve arrangement. Do not allow liquid to enter a unit that is not designed to handle it.
After bulk liquid has been removed, recover the remaining vapor through the appropriate vapor connection. Monitor system pressure, recovery-unit operation, and cylinder weight. For a low-pressure chiller, the recovery device’s high-pressure cut-out and other controls must be suitable for low-pressure service.
Verify the evacuation level
Continue recovery until the applicable evacuation level is reached. For low-pressure appliances, the required level is absolute; this is an , not a gauge vacuum. Verify the pressure with a suitable instrument.
After reaching the level, isolate the appliance and wait a few minutes. If pressure rises, refrigerant may remain in liquid pockets or oil, so continue recovery as appropriate.
Handle and close out the
Use only a designated, pressure-rated that is compatible with the refrigerant. Keep different refrigerants separate and identify the cylinder contents. Weigh the cylinder before and during recovery. Do not exceed its permitted fill limit; the EPA recovery-equipment test procedure uses an liquid fill level. Follow applicable cylinder markings, regulations, and equipment instructions.
Keep the cylinder upright, secured, and away from heat. Close its valves before disconnecting or moving it, and check for leaks. Do not exceed the marked maximum gross weight or pressure rating.
When recovery is complete, close the valves and disconnect using the approved procedure. Record the recovered refrigerant and cylinder weight, then arrange reuse, reclamation, or disposal as required.