Initial Start-Up - Carrier 23xl Start-Up, Operation And Maintenance Instructions Manual

The full refrigerant charge on the 23XL will vary with chill-
er components and design conditions, as indicated on the job
data specifications. An approximate charge may be determined
by adding the condenser charge to the cooler charge as listed in
Table 8.
Always operate the condenser and chilled water pumps
whenever charging, transferring, or removing refrigerant
from the chiller.
Use the CONTROL TEST terminate lockout function to
monitor conditions and start the pumps.
If the chiller has been shipped with a holding charge, the
refrigerant is added through the refrigerant charging valve
(Fig. 32-35, valves 7a and 7b) or to the pumpout charging con-
nection. First evacuate the nitrogen holding charge from the
chiller vessels. Charge the refrigerant as a gas until the system
pressure exceeds 68 psig (469 kPa) for R-22, and 35 psig
(141 kPa) for HFC-134a. After the chiller is beyond this pres-
sure the refrigerant should be charged as a liquid until all the
recommended refrigerant charge has been added.
TRIMMING REFRIGERANT CHARGE — T h e
chiller is shipped with the correct charge for the design duty of
the chiller. Trimming the charge can best be accomplished
when the design load is available. To trim the charge, check the
temperature difference between the leaving chilled water tem-
perature and cooler refrigerant temperature at full load design
conditions. If necessary, add or remove refrigerant to bring
the temperature difference to design conditions or minimum
differential.

INITIAL START-UP

Preparation —
Before starting the chiller, verify:
1. Power is on to the main starter, oil pump relay, tower
fan starter, oil heater relay, and the chiller control
panel.
2. Cooling tower water is at proper level and at-or-below
design entering temperature.
3. Chiller is charged with refrigerant and all refrigerant
and oil valves are in their proper operating positions.
4. Oil is at the proper level in the reservoir sight glasses.
5. Oil reservoir temperature is above 140 F (60 C) or
refrigerant temperature plus 50º F (28º C).
6. Valves in the evaporator and condenser water circuits
are open.
NOTE: If the pumps are not automatic, ensure water is circu-
lating properly.
COOLER SIZE ECONOMIZER
10,11
20,21
40
41
42
43
*Not available or retrofitable when using HFC-134a.
2 3 X L
Table 8 — Refrigerant Charges
lb
NO 600
YES 650
NO 700
YES 750
NO 900
YES 1000
NO 1000
YES 1100
NO 1100
YES 1200
NO 1200
YES 1300
Do not permit water or brine that is warmer than 110 F
(43 C) to flow through the cooler or condenser. Refrigerant
overpressure may discharge through the relief valves and
result in the loss of refrigerant charge.
7. Access the CONTROL TEST screen. Scroll down on
the TERMINATE LOCKOUT option. Press the
SELECT (to enable the chiller to start) and answer
YES to restart unit to operating mode. The chiller is
locked out at the factory in order to prevent accidental
start-up.
Dry Run to Test Start-Up Sequence
1. Disengage the main motor disconnect on the starter
front panel. This should only disconnect the motor
power. Power to the controls, oil pump, and starter
control circuit should still be energized.
2. Observe the default screen on the CVC: the Status
message in the upper left-hand corner reads, "Manu-
ally Stopped." Press the
start. If the chiller controls do not go into a start mode,
go to the Schedule screen and override the schedule or
change the occupied time. Press the
to begin the start-up sequences.
3. Verify the chilled water and condenser water pumps
have energized.
4. Verify the oil pump has started and is pressurizing the
lubrication system. After the oil pump has run about
11 seconds, the starter energizes and goes through its
start-up sequence.
5. Check the main contactor for proper operation.
6. The PIC II eventually shows an alarm for motor amps
not sensed. Reset this alarm and continue with the ini-
tial start-up.
Check Oil Pressure and Compressor Stop
1. Two minutes after start-up, note the oil pressure read-
ing on the CVC default screen. The value is equal to
the difference between the oil and evaporator pressure
transducer readings. The minimum oil pressure is 7 to
20 psi (48 to 137 kPa). The oil and evaporator pressure
transducer readings can be observed on the COM-
PRESS and HEAT-EX table. A normal full load
reading is approximately 120 psi (827 kPa) [78 psi
(538 kPa)].
2. Press the STOP softkey and listen for any unusual
sounds from the compressor as it coasts to a stop.
REFRIGERANT
HCFC-22
kg
272
295
318
340
408
454
454
499
499
544
544
590
65
or softkey to
CCN LOCAL
softkey
LOCAL
HFC-134a
lb kg
* *
* *
* *
* *
800 363
850 386
850 386
900 408
900 408
950 431
950 431
1000 454