18
Table 11 — Compressor Run Status
Chiller Start-Up Sequence
PRE-START CHECK — Once start-up begins, the controller
performs a series of pre-start tests to verify that all pre-start
alerts and safeties are within limits. Progress is shown on the
Startup Sequence screen (see Fig. 30). This screen can be ac-
cessed by touching the mode title (top blue bar) of the home
screen. Table 12 lists pre-start alert and alarm conditions.
Table 12 — Pre-Start Alerts and Alarms
*Evap trip point = 33 F (0.6 C) (water) or EVAP REFRIG TRIPPOINT
(brine).
The compressor RUN STATUS parameter on the default
screen line now reads PRESTART. If a test is not successful,
the start-up is delayed or aborted. If all tests are successful, the
chilled water pump relay energizes, and the main screen line
now reads STARTUP.
START-UP — One second after the successful pre-start
check, the chilled water and condenser water pump relays are
energized.
Five seconds later, the control monitors the chilled water
and condenser water flow devices and waits until the WATER
FLOW VERIFY TIME (service-configured, default 5 minutes)
expires to confirm water flow.
After water flow is verified, the water temperature is com-
pared to CONTROL POINT +
1
/
2
CHILLED WATER DEAD-
BAND. If the temperature is less than or equal to this value, the
control turns off the condenser pump relay and goes into RE-
CYCLE mode.
If the RECYCLE condition is not satisfied, the start-up se-
quence continues and checks the guide vane position. For a sin-
gle-stage compressor (Comp [Single = 0, Dual = 1] = 0 in
FACTORY configuration), if the guide vanes are more than
“GUIDE VANE CLOSURE AT STARTUP (default 4%)” %
open, the start-up waits until the controller closes the vanes.
For a dual-stage compressor (Comp [Single = 0, Dual = 1] = 1
in FACTORY configuration), the guide vanes are opened to the
initial position specified with GV1 Closure at Startup in the
Option Configuration menu.
If an EC/HGBP or economizer damper valve is equipped
and enabled, the control checks that the position of these valves
is fully closed.
If the vanes and valves position are verified and the oil
pump pressure difference is less than 6 psi (41.4 kPa), the oil
pump relay is energized.
The control then waits until the oil pressure difference (OIL
PRESS VERIFY TIME, operator-configured, default 40 sec-
onds) reaches a maximum of 18 psi (124 kPa). After oil pres-
sure is verified, the control waits 40 seconds for oil prelube, and
the compressor start relay energizes to start the compressor.
STATUS
NO.
STATUS
NAME
DESCRIPTION
0
OFF
STATSTOP is STOP, no alarm.
1
CTLTEST
Controls Test is active.
2
PUMPDOWN Pumpdown is active.
3
LOCKOUT
Lockout is active.
4
RECYCLE
Recycle shutdown completed on low
load in effect until the need for cooling
resumes; non-fault condition.
5
TRIPOUT
Shutdown completed due to alarm fault
condition.
6
TIMEOUT
The controller is delaying the start
sequence until the Start to Start or Stop
to Start timers have elapsed.
7
PRESTART
The chiller is in the process of system
checking before energizing the compres-
sor motor.
8
STARTUP
Normal start-up in progress.
9
AUTORST
Auto Restart in progress.
10
RAMPING
Ramp loading in progress. The chiller
has started and is gradually increasing
its load to control electrical demand
charges.
11
RUNNING
The chiller has completed ramp loading
following start-up. Normal running mode,
no override or demand limit.
12
OVERRIDE
Running with Override active.
13
DEMAND
Running with Demand Limit active. The
chiller is prevented from loading further
because it has reached an AVERAGE
LOAD CURRENT limit or a MOTOR
KILOWATTS limit.
14
SHUTDOWN Compressor shutdown in progress.
15
FREECOOL
Free Cooling in Progress
16
CONDFLSH
Condenser Flush in Progress (Note:
Available for “Marine Option” only).
Fig. 30 — Start-Up Sequence Screen
PRE-START ALERT
CONDITION
STATE
NO.
ALARM
OR
ALERT
STARTS IN 12 HOURS >= 8
100
Alert
OIL SUMP TEMP <= 140 F (60 C) AND OIL
SUMP TEMP <= EV 50 F (27.8 C)
101
Alert
CONDENSER PRESSURE >=
COND PRESS OVERRIDE – 20 psi
102
Alert
Number of recycle restart in the last 4 hours is
greater than 5
103
Alert
COMP BEARING TEMP >= COMP BEARING
ALERT– 10 F (5.5 C)
230
Alarm
COMP MOTOR WINDING TEMP >= MOTOR
TEMP OVERRIDE – 10 F (5.5 C)
231
Alarm
COMP DISCHARGE TEMP >= COMP DIS-
CHARGE ALERT– 10 F (5.5 C)
232
Alarm
EVAP_SAT < Evap trip point* +
EVAP OVERRIDE DELTA T
or
EVAP REFRIG LIQUID TEMP < Evap trip
point* + EVAP OVERRIDE DELTA T
233
Alarm
ACTUAL LINE VOLTAGE <=
UNDERVOLTAGE THRESHOLD
(n/a for UM VFDs)
234
Alarm
ACTUAL LINE VOLTAGE >=
OVERVOLTAGE THRESHOLD
(n/a for UM VFDs)
235
Alarm
Guide vane 1 has not been calibrated success-
fully
236
Alarm