60
6. Press to highlight the holiday table that is to
be viewed or changed. Each table is one holiday
period, starting on a specific date, and lasting up to
99 days.
7. Press to access the holiday table. The Con-
figuration Select table now shows the START
MONTH, START DAY, and DURATION of the holi-
day period.
8. Press or to highlight the START
MONTH, START DAY, and DURATION.
9. Press to modify the month, day, or duration.
10. Press or to change the
selected value.
11. Press to save the changes.
12. Press to return to the previous menu.
START-UP/SHUTDOWN/
RECYCLE SEQUENCE (FIG. 37)
Local Start-Up —
Local start-up (or a manual start-up) is
initiated by pressing the menu softkey on the default
ICVC screen. Local start-up can proceed when the chiller
schedule indicates that the current time and date have been
established as a run time and date, and after the internal
15-minute start-to-start and the 1-minute stop-to-start inhibit
timers have expired. These timers are represented in the START
INHIBIT TIMER and can be viewed on the MAINSTAT screen
and DEFAULT screen. The timer must expire before the chiller
will start. If the timers have not expired the RUN STATUS
parameter on the MAINSTAT screen now reads TIMEOUT.
NOTE: The time schedule is said to be “occupied” if the
OCCUPIED? parameter on the MAINSTAT screen is set to
YES. For more information on occupancy schedules, see the
sections on Time Schedule Operation (page 28), Occupancy
Schedule (page 47), and To Prevent Accidental Start-Up
page 82), and Fig. 29.
If the OCCUPIED? parameter on the MAINSTAT screen is
set to NO, the chiller can be forced to start as follows. From the
default ICVC screen, press the and soft-
keys. Scroll to highlight MAINSTAT. Press the
softkey. Highlight and select CHILLER START/STOP. Press the
softkey to override the schedule and start the chiller.
NOTE: The chiller will continue to run until this forced start is
released, regardless of the programmed schedule. To release
the forced start, highlight and select CHILLER START/STOP
from the MAINSTAT screen and press the
softkey. This action returns the chiller to the start and stop
times established by the schedule.
The chiller may also be started by overriding the time
schedule. From the default screen, press the and
softkeys. Scroll down and select the current
schedule. Scroll down and select OVERRIDE, and set the
desired override time period.
Another condition for start-up must be met for chillers that
have the REMOTE CONTACTS OPTION on the EQUIP-
MENT SERVICE, OPTIONS screen set to ENABLE. For
these chillers, the REMOTE START CONTACT parameter on
the MAINSTAT screen must be CLOSED. From the ICVC
default screen, press the and softkeys.
Scroll to high-light MAINSTAT and press the soft-
key. Scroll down the MAINSTAT screen to highlight
REMOTE START CONTACT and press the softkey.
Press the softkey to initiate the override. To end the
override, select REMOTE START CONTACT and press the
softkey.
Once local start-up begins, the PIC III performs a series of
pre-start tests to verify that all pre-start alerts and safeties are
within the limits shown in Table 5. The RUN STATUS parame-
ter on the MAINSTAT screen line now reads PRESTART. If a
test is not successful, the start-up is delayed or aborted. Failure
to verify any of the requirements up to this point will result in
the PIC III controls aborting the start and displaying the appli-
cable pre-start alert on the ICVC default screen. A pre-start
alert does not advance the starts in 12 hours counter. If the tests
are successful, the chilled liquid pump relay energizes, and the
MAINSTAT screen line now reads STARTUP.
Five seconds later, the condenser pump relay energizes.
Thirty seconds later the PIC III module monitors the chilled
liquid and condenser liquid flow devices and waits until the
LIQUID FLOW VERIFY TIME (operator-configured, default 5
minutes) expires to confirm flow. After flow is verified, the
chilled liquid temperature is compared to CONTROL POINT
plus
1
/
2
CHILLED LIQUID DEADBAND. If the temperature is
less than or equal to this value, the PIC III controls turn off the
condenser pump relay and goes into a RECYCLE mode.
NOTE: The 23XRV chillers are not available with factory-
installed external chilled liquid flow or condenser liquid
flow devices. These are available as an accessory for use
with the CCM control board.
If the liquid temperature is high enough to require cooling,
the start-up sequence continues. Tower fan control is enabled
and the oil pump starts. Oil pressure is verified between 45 sec-
onds and 5 minutes. The VFD is set to START following oil
pressure verification and the controls verify that no faults exist.
Proper compressor rotation is verified by monitoring the
discharge pressure.
The control center monitors load current to verify that the
compressor is running then steps the compressor up to target
speed. The start-to-start and service ontime timers are activated
when compressor operation is confirmed.
The controls will abort the start and display the applicable
pre-start alert on the ICVC if any of the conditions above are
not verified. Any fault after the start-up process is complete
results in a safety shutdown, advancing the STARTS IN
12 HOURS counter by one, and display of the applicable shut-
down status on the ICVC display.
23XRPIC3
Fig. 36 — Example of Holiday Period Screen
a23-1612
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