Carrier 17/19EX - Manual (Page 187)

Pumpout and Refrigerant Transfer Procedures
Preparation
The 17/19EX may come equipped with an optional pumpout compressor. The refrigerant can
be pumped for service work to either the cooler/condenser/compressor sections or the utility
vessel by using the pumpout system. The following procedures are used to describe how to
transfer refrigerant from vessel to vessel and perform machine evacuations.
Operating the Optional Pumpout Compressor
1. Be sure that the suction and the discharge service valves on the optional pumpout
compressor are open (backseated) during operation. Figure 32 shows the location of these
valves. Rotate the valve stem fully counterclockwise to open. Front seating the valve closes
the refrigerant line and opens the gage port to compressor pressure.
2. Make sure that the compressor holddown bolts have been loosened to allow free spring
travel.
3. Open the refrigerant inlet valve on the pumpout compressor.
4. Oil should be visible in the compressor sight glass under all operating conditions and during
shutdown. If oil is low, add oil as described under Optional Pumpout System Maintenance
section. The pumpout unit control wiring schematic is detailed in Figure 33 . The Optional
Pumpout System is detailed in Figure 34 .