Specifications

YORK INTERNATIONAL 23
FORM 160.48-O1
SYSTEM SHUTDOWN – PRESS STATUS
Displayed when chiller is shut down on a cycling shut-
down, safety shutdown (operator must move the “COM-
PRESSOR” switch to “STOP/RESET” in order to restart)
or operator-initiated shutdown (within 30 minutes of ini-
tial start-up). The status message consists of the day
and time of shutdown, cause of shutdown, and type of
restart required. Upon pressing “STATUS” key, “System
Shutdown Message” will be displayed for 2 seconds and
then return to
SYSTEM SHUTDOWN – PRESS STATUS
Display can be held indefinitely by depressing “DISPLAY
HOLD” key. For examples of “System Shutdown Mes-
sages”, see below.
SYSTEM SHUTDOWN MESSAGES
Day of Week Time of Day Cause of Shutdown Type of Restart
MON 10:00 AM – LOW WATER TEMP – AUTOSTART
Chiller was shut down Monday at l0:00AM because the
LCWT has decreased to a value that is 4°F below the
operator-programmed chilled liquid temperature
setpoint. However, if the setpoint is less than 40°F, the
chiller will 20 always shut down at 36°F. Further, if the
chiller is running and the setpoint is changed, the (Low
Water Temperature) cutout will be 36°F for l0 minutes in
order to eliminate nuisance trips. Finally, for brine chill-
ing applications, the LWT cutout is always 4°F below
the setpoint (The water jumper on the Micro Board must
be removed for a brine unit).
MON XX:XX AM – LOW WATER TEMP – VSD – AUTOSTART
Variable Speed Drive has shut down the chiller because
the LCWT has decreased to a value that is 4°F below
the operator-programmed chilled liquid temperature
setpoint. If the chiller is running and the setpoint is in-
creased greater than 4°F, the Variable Speed Drive will
initiate a shutdown. The shutdown is caused by LWT
contact supplied from the Variable Speed Drive. To cause
the Micro Board to monitor the Variable Speed Drive
LWT input, the non-Variable Speed Drive jumper on the
Micro Board must be removed.
MON XX:XX AM – FLOW SWITCH – AUTOSTART
Chiller is shut down because a chilled-liquid flow switch
has opened. The flow switch must open for a minimum
of 2 seconds in order to cause a shutdown. The flow
switch is checked 25 seconds into “Start Sequence Ini-
tiated” and continuously thereafter.
WARNING: HIGH PURGE PRESSURE
If the purge transducer output is indicating a pressure
greater than 95 PSIA (for 255 continuous sec.) the above
warning message is displayed alternately with the nor-
mal foreground message. When the pressure decreases
to less than 95 PSIA, the message is automatically
cleared.
MON XX:XX WARNING – EXCESS PURGE
Anytime after the first hour of chiller operation, if the
purge exhaust count equals the programmed “MAX
PURGE/HR” threshold, this message is alternately dis-
played with the normal foreground message. The day
and time displayed is the time the excess purge event
occurred. This message will be displayed until manually
cleared using the “WARNING RESET” key in the “Ser-
vice” mode. Clearing the message also resets the purge
exhaust count to zero and invokes the message
PURGES.LAST XX MIN = XX; MAX PURGES/HR = XX
While the excess purge message is displayed, the purge
exhaust count will continue to increment until the 1 hour
period has elapsed. The count is then frozen until the
excess purge message is cleared. This provides a record
of the total number of purge exhausts that occurred
within the 1 hour period that the excess purge event
occurred.
Refer to “DISPLAY DATA” key in SERVICE KEYS sec-
tion for complete explanation of purge counting.
NOTE: If the “STATUS” key is arbitrarily pressed, with-
out the operator being prompted by the
PRESS STATUS
message, this message shall be displayed:
NO MALFUNCTION DETECTED
SYSTEM RUN – LEAVING TEMP CONTROL
Displayed while the chiller is running. Indicates that the
prerotation vanes are being controlled by the leaving
chilled water temperature (LCWT). This is the normal
mode of chiller operation. Thus, if the LCWT is above
the setpoint, but pulling down rapidly, the vanes will pulse
closed as the LCWT nears the setpoint.
SYSTEM READY TO START
Indicates that the system is not running, but will start
upon application of a start signal.