Shutdown Sequence
Shutdown of the machine c an occur if any of the following events happen:
• the STOP button is press ed f or at least one second (the alar m li ght will blink once to
confirm stop command)
• recycle condition is present (see Chilled Water Recycle Mode section)
• time schedule has gone int o UNOCCUPIED mode
• remote contact opens
• the start/stop status is ov er r i dden to stop from the CCN net wo rk or the LID
When a stop signal occurs, the shutdown sequence first stops the compressor by
deactivating the start relay. A status message of ‘‘SHUTDOWN IN PROGRESS, COMPRES-
SOR DEENERGIZED’’ is di splayed. The guide van es ar e t hen brought to the closed po s it ion.
The oil pump relay and the ch ill ed water/brine pump rel ay are shut down 60 seconds aft er t he
compressor stops . The condenser water pump will be shut down w hen the
CONDENSER
REFRIGERANT TEMP
is less than the
CONDENSER PRESSURE OVERRIDE
minus 5 psi
(34 kPa) or is less than or equ al to the
ENTERING CONDENSER WATER TEMP
plus 3° F
(2° C). The stop-to-st ar t timer will now begin to count down. If the start-to-st art timer is still
greater than the value of the start-to-stop timer, then this time is now display e d on the LID.