Start-Up/Shutdown/ Recycle Sequence; Local Start-Up - Carrier 19XRV Start-Up, Operation And Maintenance Instructions Manual

START-UP/SHUTDOWN/
RECYCLE SEQUENCE (Fig. 27)
Local Start-Up
-- L_cal start-up (ora manual start-up) is
initiated by pressing the _ menu softkey on the default
ICVC scleen. Ix_c_d start-up can proceed when the chiller
schedule indicates that the CURRENT TIME and CURRENT
DATE have been established as a mn time and date, and after
the internal timers have expired. The timers include a
15-minute start-to-start timer and a l-minute stop-to-start tim-
el. which together serve to prevent excessive cycling and abuse
of the motol: The value of these timers is displayed as START
INHIBIT TIMER and can be viewed on the MAINSTAT and
DEFAULT screens. Both timel_ must expire before the chiller
will stall. If the timers have not expired, the RUN STATUS
pm'ameter on the MAINSTAT screen will read TIMEOUT.
NOTE: The time schedule is said to be "occupied" if the
OCCUPIED ? pmameter on the MAINSTAT scleen is set to
YES. For more information on occupancy schedules, see the
sections on Time Schedule Operation (page 21), Occupancy
Schedule (page 36), and To Prevent Accidental Stall-Up
(page 67), and Fig. 19.
If the OCCUPIED ? pm'ameter on the MAINSTAT screen
is set to NO, the chiller can be forced to stm't as follows. From
the default [CVC screen, press the _ and
softkeys. Scroll to highlight MAINSTAT. Pless the
softkey. Scroll to highlight CHILLER START/STOP. Press the
softkey to override the schedule and start the chiflel:
NOTE: The chiller will continue to run until this forced start is
released, regardless of the progrmnmed schedule. To release
the forced start, highlight CHILLER START/STOP fiom the
MAINSTAT screen and press the [RELEASE] softkey. This
action returns the chiller to the stmt and stop times established
by the schedule.
The chiller may also be stmted by overriding the time sched-
ule. From the default screen, press the _ and
[SCHEDULE] softkeys. Scroll down and select the current
schedule. Select OVERRIDE, and set the desiled override time.
Another condition for st;ut-up must be met for chillers that
have the REMOTE CONTACTS OPTION on the EQUIP-
MENT SERVICE screen set to ENABLE. For these chillers,
the REMOTE START CONTACT parameter on the MAIN-
STAT screen must be CLOSED. From the ICVC default
screen, press the _ and _ softkeys. Scroll to
highlight MAINSTAT and press the _ softkey. Scroll
down the MAINSTAT screen to highlight REMOTE START
CONTACT and press the _ softkey. Then, press the
softkey. To end the override, select REMOTE
CONTACTS INPUT and press the [RELEASE ] softkey.
Once local start-up begins, the PIC III performs a series of
pre-start tests to verify that all pre-start alefls and safeties are
within the limits shown in Table 7. 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. If the
tests are successful, the CHILLED WATER PUMP relay ener-
gizes, and the RUN STATUS line now reads STARTUR See
Table 9.
Five seconds latel', the CONDENSER WATER PUMP relay
energizes. Thirty seconds later the PIC III monitors the chilled
water trod condenser water flow devices and waits until the
WATER FLOW VERIFY TIME (operator-configured, default
5 minutes) expires to confirm flow. After flow is verified, the
chilled water temperature is compmed to CONTROL POINT
plus/_ CHILLED WATER DEADBAND. If the temperature is
less than or equal to this value, the PIC III turns off
the CONDENSER WATER PUMP relay and goes into a
RECYCLE mode.
NOTE: 19XRV units are not available with factou-installed
chilled water or condenser water flow devices (available as an
accesso U for use with the CCM Control board).
If the water/brine temperature is high enough, the st;u't-up
sequence continues and checks the guide vane position. If the
guide vanes are more than 4% open, the stall-up is delayed
until the PIC IIl closes the vanes. If the vanes are closed and
the oil pump pressure is less than 4 psi (28 kPa), the oil pump
relay energizes. The PIC [II then waits until the oil pressure
(OIL PRESS VERIFY TIME, operator-configured, default of
40 seconds) leaches a maximum of 18 psi (124 kPa). After oil
pressure is verified, the PIC III waits 40 seconds, and the VFD
energizes to start the compressol:
Compressor ontime and service ontime timers start, and the
complessor STARTS IN 12 HOURS counter and the number of
stalls over a 12-hour period counter advance by one.
Ftfilure to verily any of the requirements up to this point will
result in the PIC III aborting the stall and displaying the appli-
cable pre-start mode of failure on the ICVC default screen. A
pre-start failure does not advance the STARTS IN 12 HOURS
countel: Any failure after the VFD has energized results in a
safety shutdown, advances the starts in 12 hours counter by
one, and displays the applicable shutdown status on the [CVC
display. The minimum time to complete the entire prestart
sequence is approximately 185 seconds.
Table 9 -- Prestart Checks
QUANTITY CHECKED
STARTS IN 12 HOURS
COMP THRUST BRG TEMP
COMP MOTOR WINDING TEMP
COMP DISCHARGE TEMP
EVAPORATOR REFRIG TEMP
OIL SUMP TEMP
CONDENSER PRESSURE
PERCENT LINE VOLTAGE
PERCENT LINE VOLTAGE
ACTUAL GUIDE VANE POS
REQUIREMENT
< 8 (not counting recycle restarts or auto restarts after power failure)
ALERT is cleared once RESET is pressed.
< [COMP THRUST BRG ALERT] -10 ° F (5.6 ° C)
< [COMP MOTOR TEMP OVERRIDE] -10 ° F (5.6 ° C)
< [COMP DISCHARGE ALERT] -10 ° F (5.6 ° C)
< [EVAP REFRIG TRIPPOINT] + [REFRIG OVERRIDE DELTA T]
< 150 ° F (65.5 ° C) or <[EVAP REFRIG TEMP] + 50 ° F (10 ° C)
< CONDENSER PRESSURE OVERRIDE -20 PSI (138 kPa) and
< 145 psi (1000 kPa)
< [UNDERVOLTAGE THRESHOLD]
> [OVERVOLTAGE THRESHOLD]
Must have been calibrated
ALERT STATE
100
101
102
103
104
105
106
107
108
109
IF FALSE
5O