Specifications

72
4. Crack open valve 5, gradually increasing pressure in the
evacuated chiller vessel to 35 psig (241 kPa). Feed refrig-
erant slowly to prevent tube freeze-up.
5. Leak test to ensure chiller vessel integrity.
6. Open valve 5 fully.
7. Close valves 1a, 1b, 3, and 5.
8. Open chiller isolation valve 11 and any other isolation
valves, if present.
9. Turn off chiller water pumps.
DISTILLING THE REFRIGERANT
1. Transfer the refrigerant from the chiller to the pumpout
storage tank as described in the Transfer the Refrigerant
from Chiller to Pumpout Storage Tank section.
2. Equalize the refrigerant pressure.
a. Turn on chiller water pumps and monitor chiller
pressures.
b. Close pumpout and storage tank valves 2, 4, 5, and
10, and close chiller charging valve 7; open chiller
isolation valve 11 and any other chiller isolation
valves, if present.
c. Open pumpout and storage tank valves 3 and 6;
open chiller valves 1a and 1b.
d. Gradually crack open valve 5 to increase chiller
pressure to 35 psig (241 kPa). Slowly feed refriger-
ant to prevent freeze-up.
e. Open valve 5 fully after the chiller pressure rises
above the freezing point of the refrigerant. Let the
storage tank and chiller pressure equalize.
3. Transfer remaining refrigerant.
a. Close valve 3.
b. Open valve 2.
c. Turn on pumpout condenser water.
d. Run the pumpout compressor until the storage tank
pressure reaches 5 psig (34 kPa), 18 in. Hg vacuum
(41 kPa absolute) in Manual or Automatic mode.
e. Turn off the pumpout compressor.
f. Close valves 1a, 1b, 2, 5, and 6.
g. Turn off pumpout condenser water.
4. Drain the contaminants from the bottom of the storage
tank into a container. Dispose of contaminants safely.
GENERAL MAINTENANCE
Refrigerant Properties —
HFC-134a is the standard
refrigerant in the 23XRV chiller. At normal atmospheric pres-
sure, HFC-134a will boil at –14 F (–25 C), and must, therefore,
be kept in pressurized containers or storage tanks. The refriger-
ant is practically odorless when mixed with air. HFC-134a is
non-combustible at atmospheric pressure. Read the Material
Safety Data Sheet and the latest ASHRAE Safety Guide for
Mechanical Refrigeration to learn more about safe handling of
this refrigerant.
Adding Refrigerant — Follow the procedures described
in the Charge Refrigerant into Chiller section, page 63.
Removing Refrigerant — If the optional pumpout sys-
tem is used, the 23XRV refrigerant charge may be transferred
to a storage vessel or within the condenser or cooler if isolation
valves are present. Follow procedures in the Pumpout and
Refrigerant Transfer Procedures section when removing refrig-
erant from the storage tank to the chiller.
Adjusting the Refrigerant Charge — If the addi-
tion or removal of refrigerant is required for improved chiller
performance, follow the procedures given under the Trim
Refrigerant Charge section, on page 73.
Refrigerant Leak Testing — Because HFC-134a is
above atmospheric pressure at room temperature, leak testing
can be performed with refrigerant in the chiller. Use an elec-
tronic leak detector, halide leak detector, soap bubble solution,
or ultra-sonic leak detector. Be sure that the room is well venti-
lated and free from concentration of refrigerant to keep false
readings to a minimum. Before making any necessary repairs
to a leak, transfer all refrigerant from the leaking vessel. The
chiller should be leak tested at least once per year.
Refrigerant Leak Rate — ASHRAE recommends that
chillers should be immediately taken off line and repaired if the
refrigerant leakage rate for the entire chiller is more than 10%
of the operating refrigerant charge per year.
Additionally, Carrier recommends that leaks totalling less
than the above rate but more than a rate of 1 lb (0.5 kg) per year
should be repaired during annual maintenance or whenever the
refrigerant is pumped over for other service work.
Test After Service, Repair, or Major Leak — If
all refrigerant has been lost or if the chiller has been opened for
service, the chiller or the affected vessels must be pressured
and leak tested. Refer to the Leak Test Chiller section to per-
form a leak test.
REFRIGERANT TRACER — Use an environmentally ac-
ceptable refrigerant as a tracer for leak test procedures.
TO PRESSURIZE WITH DRY NITROGEN — Another
method of leak testing is to pressure with nitrogen only and use
soap bubble solution or an ultrasonic leak detector to determine
if leaks are present. This should only be done if all refrigerant
has been evacuated from the vessel.
1. Connect a copper tube from the pressure regulator on the
cylinder to the refrigerant charging valve. Never apply
full cylinder pressure to the pressurizing line. Follow the
listed sequence.
VALVE 1a1b234511
CONDITION C C C
VALVE 1a1b234511
CONDITION CCCCCC
VALVE 1a1b2345671011
CONDITION C C C C C
VALVE 1a1b2345671011
CONDITION C C C C
VALVE 1a1b2345671011
CONDITION CCCCCCCCC
WARNING
HFC-134a will dissolve oil and some non-metallic materi-
als, dry the skin, and, in heavy concentrations, may dis-
place enough oxygen to cause asphyxiation. In handling
this refrigerant, protect the hands and eyes and avoid
breathing fumes.
CAUTION
Always use the compressor pumpdown function in the
Control Test mode to turn on the evaporator pump and lock
out the compressor when transferring refrigerant. Liquid
refrigerant may flash into a gas and cause possible freeze-
up when the chiller pressure is below 35 psig (241 kPa).