Pumpout And Refrigerant Transfer Procedures; Preparation; Operating The Optional Pumpout Unit - Carrier AquaEdge 23XRV Start-Up, Operation And Maintenance Instructions Manual

PUMPOUT AND REFRIGERANT
TRANSFER PROCEDURES

Preparation

The 23XRV chiller may come equipped with an optional pumpout
storage tank, pumpout system, or pumpout compressor. The re-
frigerant can be pumped for service work to either the chiller com-
pressor evaporator vessel or chiller condenser vessel by using the
optional pumpout system. If a pumpout storage tank is supplied,
the refrigerant can be isolated in the storage tank. The following
procedures describe how to transfer refrigerant from vessel to ves-
sel and perform chiller evacuations.
CAUTION
Always run the chiller cooler and condenser liquid pumps and
always charge or transfer refrigerant as a gas when the chiller
pressure is less than 35 psig (241 kPa) for R-134a and less
than 39 psig (268 kPa) for R-513A. Below these pressures,
liquid refrigerant flashes into gas, resulting in extremely low
temperatures in the cooler/condenser tubes and possibly caus-
ing tube freeze-up.
WARNING
During transfer of refrigerant into and out of the optional stor-
age tank, carefully monitor the storage tank level gage. Do not
fill the tank more than 90% of capacity to allow for refrigerant
expansion. Overfilling may result in damage to the tank or
personal injury.
CAUTION
Do not mix refrigerants from chillers that use different com-
pressor oils. Compressor damage can result.
CONTROL POWER
TRANSFORMER
XFMR-1
69 VA
HIGH PRESSURE
SAFETY
NC OPEN > 185psig
2
SS-1
OFF
AUTO ON
2
2
3
GND
H1
H4
X2
X1
X2
1
LOW PRESSURE CONTROL
NC OPEN < 7 psia {-15.7 in. HG}
CLOSE > 9 psia {-11.6 in. HG}
Fig. 48 — 23XRV Pumpout Unit Wiring Schematic

Operating the Optional Pumpout Unit

1. Be sure that the suction and the discharge service valves on
the optional pumpout compressor are open (backseated)
during operation. Rotate the valve stem fully counterclock-
wise to open. Frontseating the valve closes the refrigerant line
and opens the gage port to compressor pressure.
2. Ensure that the compressor holddown bolts have been loos-
ened to allow free spring travel.
3. Open the refrigerant inlet valve on the pumpout compressor.
4. Oil should be visible in the pumpout unit compressor sight
glass under all operating conditions and during shutdown. If
oil is low, add oil as described under Optional Pumpout Sys-
tem Maintenance section, page 58. The pumpout unit control
wiring schematic is detailed in Fig. 48.
TO READ REFRIGERANT PRESSURES DURING PUM-
POUT OR LEAK TESTING:
1. The PIC display on the chiller control center is suitable for
determining refrigerant-side pressures and low (soft) vacuum.
To assure the desired range and accuracy when measuring
evacuation and dehydration, use a quality vacuum indicator
or manometer. This can be placed on the Schrader connec-
tions on each vessel by removing the evaporator or condenser
pressure transducer (Fig. 5-7).
2. To determine pumpout storage tank pressure, a 30 in. Hg vac-
uum –0-400 psi (–101 kPa -0-2769 kPa) compound gage is
attached to the storage tank.
3. Refer to Fig. 27-30 and 49, for valve locations and numbers.
Transfer, addition, or removal of refrigerant in spring-isolated
chillers may place severe stress on external piping if springs
have not been blocked in both up and down directions.
2 OL
C
C 2 OL
C 2 OL
L1
L2
X2
4
5 C
45
CAUTION
PUMP OUT
MTR-1
COMPRESSOR
HTR-1
8
CRANKCASE HEATER
240-600v
7
27-40 WATT
LEGEND
C — Contactor
FU — Fuse
GND — Ground
HTR — Heater
MTR — Motor
NC — Normally Closed
OL — Overload
SS — Selector Switch