Manual Operation Of The Guide Vanes - Carrier 19EF Series Start Up & Operation Manual

The full refrigerant charge on the 19EF will vary with ma-
chine components and design conditions, indicated on the
job data specifications. An approximate charge may be found
in Table 8.
Always operate the condenser and chilled water pumps
during charging operations to prevent freeze-ups. Use the
Control Test, Terminate Lockout table to monitor conditions
and start the pumps.
The refrigerant will be added through the refrigerant charg-
ing valve (Fig. 5) or to the pumpout charging connection.
First evacuate the nitrogen holding charge from the vessels.
Charge the refrigerant as a gas until the system pressure ex-
ceeds 35 psig (141 kPa) After the machine is beyond this
pressure the refrigerant should be charged as a liquid until
all of the recommended refrigerant charge has been added.
TRIMMING REFRIGERANT CHARGE — Trimming the
charge can be best accomplished when design load is avail-
able. To trim, check the temperature difference between leav-
ing chilled water temperature and cooler refrigerant temperature
at full load design conditions. If necessary, add or remove
refrigerant to bring the temperature difference to design con-
ditions or minimum differential.
Table 8 — Refrigerant Charges
19EF TOTAL REFRIGERANT CHARGE
COOLER
SIZE
lb
26 2630
56 3140
NOTE: The size of the cooler determines refrigerant charge for the
entire machine.
INITIAL START-UP
Preparation —
Before starting the machine, check that
the:
1. Power is on to the main starter, oil pump relay, tower fan
starter, oil heater relay, and the machine control
center.
2. Cooling tower water is at proper level, and at or below
design entering temperature.
3. Machine 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 140 F (60 C) or re-
frigerant temperature plus 50° F (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.
Do not permit water or brine that is warmer than 110 F
(43 C) to flow through the cooler or condenser. Refrig-
erant overpressure may discharge through the relief de-
vices and result in the loss of refrigerant charge.
7. Press RELEASE to automate the chiller start/stop value
on the Status01 table to enable the chiller to start. The
initial factory setting of this value is overridden to stop in
order to prevent accidental start-up.
Manual Operation of the Guide Vanes —
operation of the guide vanes is helpful to establish a steady
motor current for calibration of the motor amps value.
In order to manually operate the guide vanes, it is nec-
essary to override the TARGET GUIDE VANE POSITION
value which is accessed on the Status01 table. Manual con-
trol is indicated by the word ''SUPVSR!'' flashing after the
target value position. Manual control is also indicated on the
default screen on the run status line.
1. Access the Status01 table and look at the target guide vane
position (Fig. 13). If the compressor is off, the value will
read zero.
2. Move the highlight bar to the TARGET GUIDE VANE
POSITION line and press the SELECT softkey.
3. Press ENTER to override the automatic target. The screen
will now read a value of zero, and the word
''SUPVSR!'' will flash.
4. Press
RELEASE softkey to release the vanes to AUTO-
MATIC mode. After a few seconds the ''SUPVSR!'' will
disappear.
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
kg
still be energized.
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2. Look at the default screen on the LID: the Status mes-
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sage in the upper left-hand corner will show a ''Manually
Stopped'' message. Press CCN or LOCAL softkeys to
start. If not, 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 lubri-
cation system. After the oil pump has run about 11 sec-
onds, the starter will be energized and go through its start-up
sequence.
5. Check the main contactor for proper operation.
6. The PIC will eventually show an alarm for motor amps
not sensed. Reset this alarm and continue with the initial
start-up.
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. 26).
NOTE: Starter may have phase protection and will not allow
a start if the phase is not correct. Instead, a Starter Fault mes-
sage will occur if this happens.
IF ROTATION IS PROPER, allow the compressor to come
up to speed.
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the SELECT softkey,
Manual
and then press