Operating instructions
42
The 19XR is shipped with the correct charge for the design
duty of the chiller. Trimming the charge can best be accom-
plished when design load is available. To trim, check the
temperature difference between leaving 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 conditions or
minimum differential. If the unit incorporates a sight glass
(option) and has a full charge, bubbling must take place in
the upper level of the vessel.
277 616
308 635
340 653
322 694
359 712
391 725
381 907
413 962
440 1007
440 1039
477 1103
508 1157
520 1007
560 1062
589 1112
617 1156
648 1215
667 1270
* The optimised charge can be dierent from the charge shown above.
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. Evaporator and condenser water circuit valves are open.
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. Access the ‘Control test’ screen.
Scroll down to the PUMPDOWN/LOCKOUT option.
Press the SELECT button to permit chiller start-up and
select ‘YES’ to restart the unit in the operating mode.
NOTE: The unit is locked at the factory to prevent
accidental start-up.
NOTE: This does not apply to 19XRV machines.
ATTENTION: To comply with normal safety precautions
during start-up of electrical equipment the control box
must be closed during the initialisation tests on the
compressor supply circuit: it must be possible to carry out
all checks from outside the control box.
1. Disconnect the main power supply so that there is no
power to the compressor starter. Ensure direct supply
upstream of disconnect switch QF11. Ensure that
voltage is present at the control circuit terminals, oil
pump and heater. Ensure that no voltage is present at
the compressor starter terminals in particular. There
must be no voltage return from the supply from QF11.
2. If an electronic starter is used, install a voltmeter to
read the compressor starter control voltage. If necessary
short-circuit the starter fault return terminals on the
PIC control (102/103 or directly J27/8 on the ISM
board - please refer to the wiring diagram).
3. Look at the default screen on the ICVC: the status
message in the upper left-hand corner “OCCUPIED
MODE’’ shows that the unit is in occupied mode and
ready to start. If this is not the case, go to the Schedule
screen and override the schedule or change the occupied
time. Press the LOCAL softkey to begin the start-up
sequences.
4. Check that chilled water and condenser water pumps
energize.
5. 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.
6. Check that the compressor starter control signal has
been given: cut-in of the main contactor or voltage
present on the voltmeter at the starter terminals.
7. The PIC will eventually show an alarm for motor
current not sensed. Reset this alarm and continue with
the initial start-up.
1. Switch on the supply to the starter power circuit. PIC
now controls the order of the phases connected to the
voltage measurement terminals on the ISM board. If
the ICVC shows a fault, the order of phases connected
to the starter must specifically be checked.
On the 19XRV machines this verification may be
duplicated by the starter/variable frequency drive.
Please refer to the appendix starting with chapter 8.
2. After the default screen Status message states “Ready
for Start’’ press the LOCAL softkey. The PIC control
now initialises the start-up procedure.
3. When the starter is energized and the motor begins to
turn, immediately at the start-up check for clockwise
rotation (see Fig. 32 - “Rotation diagram”).
IF ROTATION IS CORRECT, allow the compressor to
come up to speed.