Carrier 19XL - Manual (Page 108)

Temperature Control During Ice Build
During ice build, the capacity control algorithm uses the WATER/BRINE CONTROL POINT
minus 5 F (2.7 C) to control the LEAVING CHILLED WATER temperature. The ECW OPTION
and any temperature reset option are ignored during ice build. The 20 mA DEMAND LIMIT
OPTION is also ignored during ice build.
Termination Of Ice Build
Ice build termination occurs under the following conditions:
1. Ice Build Time Schedule — When the Ice Build Time Schedule transitions to
UNOCCUPIED, ice build operation shall terminate.
2. ECW TEMPERATURE —Termination of compressor operation, based on temperature,
shall occur if the ICE BUILD TERMINATION is set to the ICE BUILD TERMINATION TEMP
option and the ENTERING CHILLED WATER temperature is less than the ICE BUILD
SETPOINT. If the ICE BUILD RECYCLE OPTION is set to ENABLE, a recycle shutdown
occurs and recycle start-up shall be based on LEAVING CHILLED WATER temperature
being greater than the WATER/BRINE CONTROL POINT plus RECYCLE DELTA T.
3. Remote Contacts/Ice Level Input —Termination of compressor operation occurs when ICE
BUILD TERMINATION is set to CONTACTS ONLY OPTION and the remote contacts are
open. In this case, the contacts are provided for ice level termination control. The remote
contacts can still be opened and closed to start and stop the chiller when the Ice Build Time