Chiller Shutdown Sequence - Carrier SmartVu Control Manual

When chiller type is 19XR6/7, and oil pump kept OFF for over 50 hours. The oil prelube time will be 6
minutes instead of 40 seconds.
When chiller type is 19DV, The control will check the refrigerant pump pressure difference, refrigerant
pump will be turned ON if it passed. Then controller waits until the refrigerant pump pressure difference
reaches 8 psi .After ref pressure is verified, if high side float chamber with liquid level, refrigerant pump
will be kept ON for 20 seconds; if not, refrigerant pump will be kept ON until there is liquid level, and then
kept on 10 seconds after that.
The compressor start relay energizes to start the compressor.

5.4. Chiller Shutdown Sequence

Chiller shutdown begins if any of the following occurs:
- In local mode, Local OFF button is pressed
- In any mode, A recycle condition is present (see Recycle Mode section)
- In Network or local schedule mode, the time schedule has gone into unoccupied mode when in
Network or Local Schedule control mode
- In any mode, The chiller protective limit has been reached and chiller is in alarm
- In network mode, The start/stop status (CHIL_S_S) is overridden to stop from the network when
in Network mode
- In remote mode, Remote Start/Stop contact is closed.
If the chiller is normally shutdown from running, soft stop shutdown will be performed. The soft stop
f eature closes the guide vanes of the compressor automatically if a non-alarm stop signal occurs before
the compressor motor is deenergized.
Any time the compressor is directed to STOP (except in the cases of a fault shutdown), the guide vanes
are directed to close and VFD will be command to minimum speed for variable speed compressor, and
the compressor shuts off when any of the following is true:
- PERCENT LOAD CURRENT (%) drops below the SOFT STOP AMPS THRESHOLD
- ACTUAL GUIDE VANE POSITION drops below 4%
- 4 minutes have elapsed after initinize the stop
When any one of the above condition is true, the shutdown sequence stops the compressor by
deactivating the compressor start relay.
Then the guide vane shall be closed and stay at the fully closed position.
When chiller type is 19XR2~5/C/D/E/V/F, the oil pump relay will be Turned OFF after 60 seconds post
lube.
When chiller type is 19XR6/7, the oil pump relay will be Turned OFF after 120 seconds post lube.
SRDC-UG-2-14-000
19 Series Carrier®
–
TM
SmartVu
Controls IOM
REVISION DATE
2.3 Dec 4, 2020
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