19XR (PIC II) Hermetic Centrifugal Liquid Chillers 50 Hz - Carrier

5 - INITIAL START-UP
5.1 - Preparation
Before starting the chiller, check that the:
1. Power is on to the main starter, oil pump relay, tower fan
starter, oil heater relay, and the chiller control centre.
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 position.
4. Oil is at the proper level in the reservoir sight glasses.
5. Oil reservoir temperature is above 60°C or refrigerant
temperature plus 28°C.
6. Valves in the evaporator and condenser water circuits are
open. NOTE: If pumps are not automatic, make sure water
is circulating properly.
NOTE: If the pumps are not automatic, check that the water
is circulating correctly.
WARNING: Do not permit water or brine that is warmer than
52°C to flow through the cooler or condenser. Refrigerant
overpressure may discharge through the relief devices and
result in the loss of refrigerant charge.
7. 'Control test' screen access
At the control screen press the scroll keys to access the
start-up menu option (Terminate lockout option).
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Press the selection that permits chiller start-up and answer
'YES' to restart it in operating mode. The unit is locked at
the factory to prevent accidental start-up.
5.2 - Dry Run to Test Start-Up Sequence
1. Disengage the main motor disconnect (QF101 for the
factory-mounted starter) 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. Look at the default screen on the local interface: the Status
message in the upper left-hand corner will read, “Manually
Stopped’’. Press CCN or Local to 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
LOCAL softkey to begin the start-up sequences.
3. Check that chilled water and condenser water pumps
energize.
4. Check that the oil pump starts and pressurizes the lubrication
system. After the oil pump has run about 45 seconds,
the starter will be energized and go through its start-up
sequence.
5. Check the main contactor for proper operation.
6. The PIC II will eventually show an alarm for motor amps
not sensed. Reset this alarm and continue with the initial
start-up.
5.3 - Check Rotation
1. Engage the main motor disconnect on the front of the
starter panel. The motor is now ready for rotation check.
2. After the default screen Status message states “Ready for
Start’’ press the LOCAL softkey; start-up checks will be
made by the control.
3. When the starter is energized and the motor begins to
turn, check for clockwise rotation (Fig. 27).
IF ROTATION IS PROPER, allow the compressor to come
up to speed.
IF THE MOTOR ROTATION IS NOT CLOCKWISE (as
viewed through the sight glass), reverse any 2 of the 3 incoming
power leads to the starter and recheck rotation.
CAUTION: Do not check motor rotation during coastdown.
Rotation may have reversed during equalization of vessel
pressures.
ROTATION
Fig. 27 - Rotation diagram
Correct motor rotation is clockwise when viewed through
turbine sight glass.
To check rotation, energize compressor motor momentarily.
Do not let machine develop condenser pressure. Check rotation
immediately.
Allowing condenser pressure to build or checking rotation
while machine coasts down may give a false indication due to
gas pressure equalizing through compressor.
5.4 - Check Oil Pressure and Compressor Stop
1. When the motor is up to full speed, note the differential
oil pressure reading on the CVC default screen. It should
be between 124 to 206 kPa.
2. Press the Stop button and listen for any unusual sounds
from the compressor as it coasts to a stop.
5.5 - To Prevent Accidental Start-Up
A chiller STOP override setting may be entered to prevent accidental
start-up during service or whenever necessary. Access
the MAINSTAT screen and using the NEXT or PREVIOUS
softkeys, highlight the CHILLER START/STOP parameter.
Override the current START value by pressing the SELECT
softkey. Press the STOP softkey followed by the ENTER softkey.
The word SUPVSR! displays on the CVC indicating the
override is in place.
To restart the chiller the STOP override setting must be removed.
Access the MAINSTAT screen and using NEXT or PREVIOUS
softkeys highlight CHILLER START/STOP. The 3 softkeys
that appear represent 3 choices:
START - forces the chiller ON
STOP - forces the chiller OFF
RELEASE - puts the chiller under remote or schedule
control.