Carrier 17 Start Up & Operation Manual

Contents

PUMPOUT AND REFRIGERANT TRANSFERPROCEDURESPreparation — The 17/19EX may come equipped withan optional pumpout compressor. The refrigerant can be pumpedfor service work to either the cooler/condenser/compressorsections or the utility vessel by using the pumpout system.The following procedures are used to describe how to trans-fer refrigerant from vessel to vessel and perform machineevacuations.Operating the Optional Pumpout Compressor1. Be sure that the suction and the discharge service valveson the optional pumpout compressor are open (back seated)during operation. Figure 32 shows the location of thesevalves. Rotate the valve stem fully counterclockwise toopen. Front seating the valve closes the refrigerant lineand opens the gage port to compressor pressure.2. Make sure that the compressor holddown bolts have beenloosened 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 underall operating conditions and during shutdown. If oil islow, add oil as described under Pumpout System Main-tenance section, page 82. The pumpout unit control wir-ing schematic is detailed in Fig. 33. The Optional Pum-pout System is detailed in Fig. 34.TO READ REFRIGERANT PRESSURES during pumpoutor leak testing:1. The LID display on the machine control center is suitablefor determining refrigerant-side pressures and low (soft)vacuum. For evacuation or dehydration measurement, usea quality vacuum indicator or manometer to ensure thedesired range and accuracy. This can be placed on theSchrader connections on each vessel (Fig. 7 and 8) byremoving the pressure transducer.2. To determine utility vessel pressure, a 30 in.-0-400 psi(-101-0-2760 kPa) gage is attached to the vessel.3. Refer to Fig. 32 for valve locations and numbers.Transfer, addition, or removal of refrigerant in spring-isolated machines may place severe stress on externalpiping if springs have not been blocked in both up anddown directions.NOTE: Location of pumpout compressor may vary depending on ma-chine arrangement.Fig. 32 — Pumpout Arrangement and Valve Number Locations (12-ft Vessel Shown)64