Refrigerant Leak Rate; Test After Service, Repair, Or Major Leak; Repair The Refrigerant Leak, Retest, And Apply Standing Vacuum Test; Trim Refrigerant Charge - Carrier AquaEdge 23XRV Start-Up, Operation And Maintenance Instructions Manual

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 operating refrigerant charge per year.
Additionally, Carrier recommends that leaks totaling 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 chiller has been opened for ser-
vice, the chiller or the affected vessels must be pressured and leak
tested. Refer to the Leak Test Chiller section to perform a leak test.
REFRIGERANT TRACER
Use an environmentally acceptable 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 de-
termine if leaks are present. This should only be done if all refrig-
erant has been evacuated from the vessel.
1. Connect a copper tube from the pressure regulator on the cyl-
inder to the refrigerant charging valve. Never apply full cylin-
der pressure to the pressurizing line. Follow the listed
sequence.
2. Open the charging valve fully.
3. Slowly open the cylinder regulating valve.
4. Observe the pressure gage on the chiller and close the regulat-
ing valve when the pressure reaches test level. Do not exceed
140 psig (965 kPa).
5. Close the charging valve on the chiller. Remove the copper
tube if no longer required.
Repair the Refrigerant Leak, Retest, and Apply
Standing Vacuum Test
After pressurizing the chiller, test for leaks with a soap bubble
solution, an electronic leak detector, a halide torch, or an ultrason-
ic leak detector. Bring the chiller back to atmospheric pressure, re-
pair any leaks found, and retest.
After retesting and finding no leaks, apply a standing vacuum test.
Then dehydrate the chiller. Refer to the Chiller Dehydration in the
Before Initial Start-Up section, page 32.

Trim Refrigerant Charge

If it becomes necessary to adjust the refrigerant charge to obtain
optimum chiller performance, operate the chiller at design load
and then add or remove refrigerant slowly until the difference be-
tween LEAVING CHILLED LIQUID chilled liquid temperature
and the EVAP REFRIG LIQUID TEMP reaches design condi-
tions. Do not overcharge. For superheat information, see the Trou-
bleshooting Guide section on page 59.
Refrigerant may be added either through the optional storage tank
or directly into the chiller as described in the section entitled0...
Refrigerant Charging.
To remove any excess refrigerant, follow the procedure in Trans-
fer Refrigerant from Chiller to Storage Tank Vessel section,
Steps 1a, b on page 50.

WEEKLY MAINTENANCE

Check the Lubrication System

Mark the oil level on the oil sump sight glasses and observe the
level each week while the chiller is running. Check the moisture
indicator on the motor cooling line.
If the level goes below the bottom of the oil sump sight glass, the
oil reclaim system must be checked for proper operation. The oil
reclaim system is operating properly if the level in the oil sump in-
creases after running the chiller near full load with a 95°F (35°C)
or higher CONDENSER SATURATED TEMPERATURE for
1 hour. If additional oil is required, add it through the oil charging
valve (Fig. 2-7). A hand pump is required for adding oil against re-
frigerant pressure. The oil charge for the 23XRV chiller is 10 gal-
lons (38 L).
The oil must meet Carrier's specifications for the 23XRV chillers.
Refer to Changing Oil and Oil Filter section. Any oil that is added
should be logged by noting the amount and date in Fig. 47 on
page 44. Any oil that is added due to oil loss not related to service
will eventually return to the sump. Excess oil must be removed
when the level is above the top of the oil sump sight glass.
A 530-watt oil sump heater and 1000W second stage heater are
controlled by the PIC6 controls to maintain oil temperature above
140°F (60°C) or EVAPORATOR SATURATED TEMPERA-
TURE plus 53°F (29.4°C) when the compressor is off (see the
Controls section on page 17). The PIC6 Status Output menu dis-
plays which heater is energized. If the Output menu shows that the
sump heater is energized, but the sump is not heating up, the pow-
er to the oil sump heater may be off or the oil level may be too low.
Check the oil level, the sump oil heater contactor voltage, and oil
heater resistance.
The PIC6 controls will not permit compressor start-up if the oil
temperature is less than 140°F (60°C) or EVAPORATED SATU-
RATED TEMPERATURE plus 15°F (8.3°C), whichever is low-
er. The control will continue with start-up only after the tempera-
ture is within limits.

SCHEDULED MAINTENANCE

Establish a regular maintenance schedule based on the actual
chiller requirements such as chiller load, run hours, and cooler
and condenser liquid quality. The time intervals listed in this sec-
tion are offered as guides to service only. Jobsite conditions may
dictate that maintenance schedule is performed more often than
recommended.
NOTE: The Optional Extended Warranty includes specific
maintenance requirements and service intervals that must be
documented. See specific details in the Optional Extended War-
ranty agreement.

Service Ontime

In the Runtime menu the PIC6 controller captures Service Run-
time and other service relevant information. This value should be
reset to zero by service person or operator each time major service
work is completed so that time between service can be seen.

Inspect the Control Center

Maintenance is generally limited to general cleaning and tighten-
ing of connections. Vacuum the control center enclosure to elimi-
nate dust build-up. In the event of chiller control malfunctions, re-
fer to the Troubleshooting Guide section for control checks and
adjustments.
Power connections on newly installed equipment may relax and
loosen after a month of operation. Turn off power and retighten;
check annually thereafter.
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